LSS Mocks - User contributions [en-ca]

WebSky 2.0 Mocks for next-gen CMB and LSS surveys

2026-05-23T06:42:52Z

Njcarlson: Created page with "The WebSky2.0 mocks for next-generation CMB and LSS surveys are soon-to-be published here. Stay tuned for our upcoming paper!"

The WebSky2.0 mocks for next-generation CMB and LSS surveys are soon-to-be published here. Stay tuned for our upcoming paper!

Large Scale Structure Mocks

2026-05-23T06:42:16Z

Njcarlson: /* WebSky2.0 Mocks */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky2.0_Mocks_for_next-generation_CMB_and_LSS_surveys WebSky2.0 Mocks for next-generation CMB and LSS surveys] ===
Data to accompany ''The WebSky2.0 Mocks for next-generation CMB and LSS surveys'' - N. J. Carlson et al. in prep.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_CII WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany [https://arxiv.org/abs/2510.18312 ''The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity'' - N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2026)]

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2026-05-23T06:41:44Z

Njcarlson:

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_2.0_Mocks_for_next-generation_CMB_and_LSS_surveys WebSky2.0 Mocks] ===
Data to accompany ''The WebSky2.0 Mocks for next-generation CMB and LSS surveys'' - N. J. Carlson et al. in prep.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_CII WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany [https://arxiv.org/abs/2510.18312 ''The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity'' - N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2026)]

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2026-05-23T06:40:09Z

Njcarlson:

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_2.0_Mocks_for_Next-Generation_CMB_and_LSS_surveys CMB WebSky2.0 Mocks] ===
Data to accompany ''The WebSky2.0 Mocks for next-generation CMB and LSS surveys'' - N. J. Carlson et al. in prep.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_CII WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany [https://arxiv.org/abs/2510.18312 ''The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity'' - N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2026)]

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2026-05-23T06:36:19Z

Njcarlson: /* Simulation Products */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky2 WebSky2.0 Mocks] ===
Data to accompany ''The WebSky2.0 Mocks for next-generation CMB and LSS surveys'' - N. J. Carlson et al. in prep.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_CII WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany [https://arxiv.org/abs/2510.18312 ''The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity'' - N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2026)]

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

WebSky CII

2025-10-24T13:59:33Z

Njcarlson: /* Data Access */

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [[https://arxiv.org/abs/2510.18312 2510.18312]].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
The WebSky [CII] publicly released data can be found [http://mocks.cita.utoronto.ca/data/websky_cii/ at this link]. Please see the file <code>README.txt</code> for instructions on how to interpret these data.



= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). [https://arxiv.org/abs/2510.18312 [2510.18312]].

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite [https://arxiv.org/abs/1907.13600 1907.13600]). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-22T06:32:01Z

Njcarlson: /* Data Access */

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [[https://arxiv.org/abs/2510.18312 2510.18312]].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
<code>This section is under construction, data should be available starting Wednesday, October 22 around mid-day (ET).</code>

The WebSky [CII] publicly released data can be found [http://mocks.cita.utoronto.ca/data/websky_cii/ at this link]. Please see the file <code>README.txt</code> for instructions on how to interpret these data.



= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). [https://arxiv.org/abs/2510.18312 [2510.18312]].

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite [https://arxiv.org/abs/1907.13600 1907.13600]). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-22T04:22:44Z

Njcarlson:

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [[https://arxiv.org/abs/2510.18312 2510.18312]].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
This section is under construction, data should be available starting Wednesday, October 22 around mid-day (ET).

The WebSky [CII] publicly released data can be found [http://mocks.cita.utoronto.ca/data/websky_cii/ here].



= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). [https://arxiv.org/abs/2510.18312 [2510.18312]].

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite [https://arxiv.org/abs/1907.13600 1907.13600]). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-22T04:21:36Z

Njcarlson: /* Acknowledgments */

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [2510.XXXXX].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
This section is under construction, data should be available starting Wednesday, October 22 around mid-day (ET).

The WebSky [CII] publicly released data can be found [http://mocks.cita.utoronto.ca/data/websky_cii/ here].



= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). [https://arxiv.org/abs/2510.18312 2510.18312].

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite [https://arxiv.org/abs/1907.13600 1907.13600]). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-21T23:28:14Z

Njcarlson: /* Data Access */

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [2510.XXXXX].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
This section is under construction, data should be available starting Wednesday, October 22 around mid-day (ET).

The WebSky [CII] publicly released data can be found [http://mocks.cita.utoronto.ca/data/websky_cii/ here].



= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). https://arxiv.org/abs/2510.XXXXX.

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite https://arxiv.org/abs/1907.13600). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-21T23:17:56Z

Njcarlson:

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [2510.XXXXX].

<gallery mode="packed-hover" heights="300px">
File:WebSky_CII_Mock_maps.png | [[Media:WebSky_CII_Mock_maps.png|Websky [CII] mock maps]]
</gallery>

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
This section is under construction, data should be available starting Wednesday, October 22 around mid-day (ET).

Data, including [http://mocks.cita.utoronto.ca/data/websky_cii/ here].


= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). https://arxiv.org/abs/2510.XXXXX.

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite https://arxiv.org/abs/1907.13600). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

File:WebSky CII Mock maps.png

2025-10-21T23:16:09Z

Njcarlson: WebSky [CII] Mock maps

== Summary ==
WebSky [CII] Mock maps

WebSky CII

2025-10-21T23:08:59Z

Njcarlson:

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [2510.XXXXX].

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
Data, including [http://mocks.cita.utoronto.ca/data/websky_cii/ here].


= Acknowledgments =

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication which makes use of the simulation data above, and ask you to cite the following papers:

N. J. Carlson, J. R. Bond, D. T. Chung, P. Horlaville and T. Morrison (2025). "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity", ''JCAP'' (submitted). https://arxiv.org/abs/2510.XXXXX.

"The sky simulations used in this paper were developed by the WebSky Mocks Collaboration, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite https://arxiv.org/abs/1907.13600). SciNet is funded by: the Canada Foundation for Innovation under the auspices of the Digital Research Alliance of Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

WebSky CII

2025-10-21T22:58:56Z

Njcarlson:

This page is the home of additional figures and public data from the WebSky [CII] Mocks for the CCAT Observatory presented in the paper "The WebSky [CII] Forecasts and the search for primordial intermittent non-Gaussianity" [2510.XXXXX].

In the [[WebSky CII#Data Access|Data Access]] section, you will find publicly available [[Peak Patch and WebSky#The Peak Patch simulations|Peak Patch]] and [[Peak Patch and WebSky#The WebSky simulations|WebSky]] simulation results, as well as a readme explaining the file system.

Additional figures will be uploaded soon!

= Data Access =
Data, including [http://mocks.cita.utoronto.ca/data/websky_cii/ here].

WebSky CII

2025-10-16T07:09:23Z

Njcarlson:

More content coming soon!

= Data =
Data, including [http://mocks.cita.utoronto.ca/data/websky_cii/ here].

Peak Patch and WebSky

2025-09-30T14:46:08Z

Njcarlson: /* Notes */ skiing

The Peak Patch and WebSky simulations are a highly efficient tool for modelling the [https://en.wikipedia.org/wiki/Observable_universe#Large-scale_structure large-scale structure] of the universe.

=The Peak Patch simulations=
The Peak Patch simulations[1,2,3] model the distribution of dark matter (DM) in the universe by mapping out catalogues of [https://en.wikipedia.org/wiki/Dark_matter_halo DM halos]. While observations do support halos of DM surrounding most galaxies and clusters, these structures do not have well defined boundaries, so in simulations we must make a choice of where we define the edge of the halo. Typically what is done is to choose the [https://en.wikipedia.org/wiki/Virial_mass#Virial_radius virial radius] within which DM particles are gravitationally bound. In <math>\Lambda</math>CDM cosmology, this corresponds to a halo with an average density about <math>\Delta_c=179</math> times the mean matter density of the universe. Since this is subject to changes in the model parameters, a factor <math>\Delta_c=200</math> is conventionally used, so we do the same.

For the most up-to date description of the Peak Patch algorithm for identifying DM halos, see [https://arxiv.org/abs/1810.07727 arXiv:1810.07727] [4].

For a summary of the Peak Patch algorithm:

# Generate <math>\delta_L(\mathbf{x})</math> field: as initial conditions, Peak Patch uses a linear-theory matter overdensity field <math>\delta_L(\mathbf{x})</math>, which is the matter overdensity <math>\delta(\mathbf{x}) = \rho_m(\mathbf{x},t) / \bar{\rho}_m(t) - 1</math> at a time <math>t</math> sufficiently early in the history of the universe that linear theory is a suitable approximation to the dynamics that formed it. <math>\delta_L(\mathbf{x})</math> can either by read from a file or generated from a [https://en.wikipedia.org/wiki/Matter_power_spectrum power spectrum] (which describe the number of structures of different sizes that we observe in the universe).
# Smooth and find peaks: the <math>\delta_L(\mathbf{x})</math> field is then smoothed at a series of scales by convolving with top hat functions (e.g. see section 3.2 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]). This removes any fluctuations smaller than about the top-hat function's cutoff radius <math>R_\mathrm{th}</math> allowing us to isolate just structures in <math>\delta_L(\mathbf{x})</math> larger than <math>R_\mathrm{th}</math>. Peaks in each filtered density field are found, these are candidate sites where dark matter halos may form.
# Ellipsoidal collapse: dark matter halos are gravitationally bound collections of dark matter, and therefore [https://en.wikipedia.org/wiki/Virial_theorem#Dark_matter virialised]. To determine if a given peak will collapse to form a virialised halo, we model it as a uniform-density sphere of radius <math>R_\mathrm{th}</math> (the top-hat filter radius at which the peak was identified), and allow it to collapse ellipsoidally (e.g. see section 3.3 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]) subject to the local strain of the <math>\delta_L(\mathbf{x})</math> field. If the collapse has enough time to reach a density contrast characteristic of virialised structure by time <math>t</math>, it is saved as a candidate halo of radius <math>R_\mathrm{th}</math>, or mass <math>M = \bar{\rho}_{m}(t_0) \frac{4}{3} \pi R_\mathrm{th}^3</math>.Peak Patch can either produce single-redshift simulations, where all halos collapse until the same time <math>t</math>, or light cone simulations where each halo is evolved only until the age it appears to be at relative to a specified observer (so <math>t</math> is the light travel time to the halo). The latter is ideal for making sky maps.
# Merging and exclusion: because halo candidates are found at multiple filter scales, overlaps are inevitable. So a merging and exclusion algorithm is run with any halo entirely inside another being tossed out and halos overlapping regions partially allotted to each halo to avoid double counting mass.
# Displacement to final state halos: up to this point, we have been working in Lagrangian space, essentially determining what mass in the initial conditions fields will form halos. But as matter collapses into halos, these halos will also move relative to one another. Most of the highly nonlinear dynamics occurs within DM halos, so the displacement of the halos themselves can be accomplished with 2nd order Lagrangian perturbation theory.

The DM halo catalogues generated by Peak Patch have been validated by <math>N</math>-body simulations[4], achieving similar results with much greater computational efficiency. Peak Patch has performed favourably compared to other halo-finders[5,6,7].

Peak Patch is additionally a particularly powerful tool for studying beyond-standard-model (BSM) cosmologies because the simulation has built-in support for varying <math>\Lambda</math>CDM model parameters and [https://en.wikipedia.org/wiki/Non-Gaussianity primordial non-Gaussianities] of a number of forms informed by a range of early-universe physics phenomena. Because it employs only approximate dynamics, complete knowledge of the BSM equations of motion is not required, allowing us to probe wider parameter space.

Coupled with WebSky, Peak Patch light-cone runs can be used to generate mock sky maps for observatories and have been used extensively by ACT in recent years to make CMB foreground mock maps. The WebSky algorithm is summarised in the next section.

=The WebSky simulations=
The WebSky[8] simulations produce mock sky maps from DM halo catalogues in a range of observables. Mock sky maps are simulated maps of the sky that are statistically analogous to maps of the sky made by observatories. They don't reproduce our particular universe, but they produce one with the same statistics meaning that you will not have galaxies in the exact same locations as the universe as we observe it, but statistical measures such as correlation functions and probability density functions will be reproduced.

The WebSky algorithm translates a light-cone DM halo catalogue to a map of the sky. Light-cone runs have a specified observer position, so mapping is done by calculating an accumulated signal from all the halos along a given line of sight. The signal from each halo, or response function, is based on an assumption of a spherically symmetric pressure profile[9,10,11,12] (which we refer to as a "BBPS" profile after the authors). Each response function is then built from up to three components
* a halo contribution: for signals that are proportional to DM halo density, the halo contribution relates the BBPS pressure profile to the response in an observable.
* a field contribution: for signals that are affected by the exterior of the halo, not just the dense virialised core, an extension to the BBPS profile is used.
* a halo occupation distribution (HOD) model: for signals that are affected by point-source emission from galactic centres, a HOD model is used. In this model, there is assumed to be a large central galaxy in each halo, larger halos then also have a series of satellite galaxies randomly distributed around it with a PDF related to the BBPS profile.

Currently, supported WebSky response functions are:
* [https://en.wikipedia.org/wiki/Sunyaev%E2%80%93Zeldovich_effect Sunyaev Zel'dovich (SZ) effects]
** thermal Sunyaev Zel'dovich (tSZ) effect caused by scattering of CMB photons by electrons in hot gas clouds
** kinetic/kinematic Sunyaev Zel'dovich (kSZ) effect caused by scattering of CMB photons by electrons in bulk flows of gas
* weak gravitational lensing [https://en.wikipedia.org/wiki/Gravitational_lensing_formalism#Convergence_and_deflection_potential convergence maps] defining the amount of magnification caused by weak gravitational lensing by galaxy clusters
* [https://en.wikipedia.org/wiki/Cosmic_infrared_background cosmic infrared background] maps showing the emission of infrared photons from dusty star forming regions
* [https://en.wikipedia.org/wiki/Intensity_mapping line intensity maps]
** HI 21 cm line emission from a hyperfine electron spin flip transition in neutral hydrogen producing a photon with a wavelength of about 21 cm. 21 cm emission could provide a tantalising glimpse into the [https://en.wikipedia.org/wiki/Reionization epoch of reionisation] and the formation of the first strs.
** CII emission line at <math>\nu=1897\text{ GHz}</math> from a fine structure transition in singly ionised carbon
** CO(1-0) line emission from carbon monoxide based on a model by Li, et al. 2016[13]
** CO(2-1) line emission from carbon monoxide based on a model by Zack Li, Dongwoo Chung, et al. in prep.

For the most up to date description of WebSky, see the paper [https://arxiv.org/abs/2001.08787 arXiv:2001.08787][8], and stay tuned for the release of WebSky2.0, which will feature fully lensed maps generated from a suite of primordial non-Gaussianity models.

=Notes=
1. WebSky has two pronunciations wɛbskaɪ and wɛbskiː which are understood to exist in superposition
<math> | \text{WEB} \rangle \otimes \left( \frac{ | \text{sky} \rangle + | \text{ski} \rangle }{ \sqrt{2} } \right) </math>.

=References=
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. I. Algorithms", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103....1B/abstract 1996ApJS..103....1B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. II. Validation", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...41B/abstract 1996ApJS..103...41B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. III. Application to Clusters", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...63B/abstract 1996ApJS..103...63B].
# Stein, G., Alvarez, M. A. and Bond, J. R. (2018) "The mass-Peak Patch algorithm for fast generation of deep all-sky dark matter halo catalogues and its N-Body validation", [https://arxiv.org/abs/1810.07727 arXiv:1810.07727].
# Lippich, M., et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices - I. Correlation function", [https://arxiv.org/abs/1806.09477 arXiv:1806.09477].
# Blot, L. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices II: Power spectrum multipoles", [https://arxiv.org/abs/1806.09497 arXiv:1806.09497].
# Colavincenzo, M. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices III: Bispectrum", [https://arxiv.org/abs/1806.09499 arXiv:1806.09499].
# Stein, G., Alvarez, M. A., Bond, J. R., van Engelen, A. and Battaglia, N. (2020) "The Websky Extragalactic CMB Simulations", [https://arxiv.org/abs/2001.08787 arXiv:2001.08787].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. I. The Influence of Feedback, Non-thermal Pressure, and Cluster Shapes on Y-M Scaling Relations", [https://arxiv.org/abs/1109.3709 arXiv:1109.3709].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich Surveys II: Deconstructing the Thermal SZ Power Spectrum", [https://arxiv.org/abs/1109.3711 arXiv:1109.3711].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2013) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. III. Measurement Biases and Cosmological Evolution of Gas and Stellar Mass Fractions", [https://arxiv.org/abs/1209.4082 arXiv:1209.4082].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2015) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. IV. Characterizing Density and Pressure Clumping due to Infalling Substructures", [https://arxiv.org/abs/1405.3346 arXiv:1405.3346].
# Li, T. Y., Wechsler, R. H., Devaraj, K. and Church, S. E. (2015) "Connecting CO Intensity Mapping to Molecular Gas and Star Formation in the Epoch of Galaxy Assembly", [https://arxiv.org/abs/1503.08833 arXiv:1503.08833]

WebSky CII

2025-09-17T23:20:18Z

Njcarlson: Created page with "Content coming soon!"

Content coming soon!

Large Scale Structure Mocks

2025-09-17T23:19:52Z

Njcarlson: /* Simulation Products */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/WebSky_CII WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany N. J. Carlson et al 2025 in prep.

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Websky cii

2025-09-17T23:18:35Z

Njcarlson: Created page with "..."

...

Large Scale Structure Mocks

2025-09-17T23:18:18Z

Njcarlson: /* Simulation Products */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/websky_cii WebSky CII Forecasts & Primordial Non-Gaussianity] ===
Data to accompany N. J. Carlson et al 2025 in prep.

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Lensed cib

2024-08-15T15:48:38Z

Njcarlson: /* Simulation Products */

On this page you will find simulation products and supplementary figures to accompany the paper [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

= Simulation Products =

Unlensed CIB mocks from this work can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/unlensed here], and lensed CIB mocks can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/lensed here]. Python scripts for post processing are available [http://mocks.cita.utoronto.ca/data/lensed_cib/post_processing_scripts here].


= Supplementary Figures =

<gallery mode="packed-hover" heights="500px">
File:slice_lensing_vFeb2024.png | [[Media:slice_lensing_vFeb2024.png|Slice Lensing]]
</gallery>
Figure 1: CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell (<math>\Delta z = 0.2</math>) within our Websky CIB model. The CIB intensity increases from <math>z = 0</math> to <math>z = 1.4</math>, peaks around <math>z = 1.4</math> to <math>1.6</math>, then decreases until it is almost non-existent by <math>z = 4</math>. The lensing kernels, defined as <math>W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big]</math> with <math>z_i^{\text{src}}</math> being the midpoint of each redshift shell in <math>z</math>-space, typically peak around half of its extent, although they display some skew towards where the CIB intensity is highest, especially as we integrate over more redshifts. The RMS deflection steeply increases at first from <math>0.34~\mathrm{arcmin}</math> for the first lensed shell, up to <math>1.7~\mathrm{arcmin}</math> for the last shell.

<gallery mode="packed-hover" heights="500px">
File:deck_of_cards_v5.png | [[Media:deck_of_cards_v5.png|Deck of cards]]
</gallery>
Figure 2: A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell <math>\Delta z = 0.2</math>. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the "self-lensing" effect substantially. Note that the CIB intensity visibly thins out by <math>z = 3</math>, while the integrated lensing convergence becomes brighter at higher redshifts.

<gallery mode="packed-hover" heights="500px">
File:animation.gif | [[Media:animation.gif|Animation]]
</gallery>
Figure 3: HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small (<math>0.5^\circ \times 0.5^\circ</math>) patch of sky centered on <math>z = 1.1</math>. Here, a "lensed" galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by comparing the Unlensed and Deflected, and the magnification effect by comparing the Deflected and Lensed.

<gallery mode="packed-hover" heights="500px">
File:Websky_vs_Planck_unlensed_fluxcut_mean_no_err_Feb2024.png | [[Media:Websky_vs_Planck_unlensed_fluxcut_mean_no_err_Feb2024.png|WebSky vs Planck unlensed]]
</gallery>
Figure 4: Statistics of the unlensed CIB maps from the Websky simulations at the three Planck frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at <math>\ell > 1000</math>. We note that the Websky bispectra are mostly within Planck error bars even though only the power spectra were fit to match those of Planck's. While we do not plot the error bars for Websky values as there is only one realization, one can estimate the level of uncertainty from the scatter especially for the bispectra and kurtosis.

<gallery mode="packed-hover" heights="500px">
File:unlensed_vs_no_kapmax_with_gamma_smoothed_all_freq_fluxcut_Planck_mean_Feb2024.png | [[Media:unlensed_vs_no_kapmax_with_gamma_smoothed_all_freq_fluxcut_Planck_mean_Feb2024.png|WebSky unlensed vs no kapmax with sigma smoothed]]
</gallery>
Figure 5: The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2% for all three frequencies, the bispectra and kurtosis change by 10 to 40% at low <math>\ell</math>. The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for Planck at lower frequencies.

<gallery mode="packed-hover" heights="500px">
File:Websky_vs_Planck_with_gamma_lensed_bl_all_ebars_Feb2024.png | [[Media:Websky_vs_Planck_with_gamma_lensed_bl_all_ebars_Feb2024.png|Websky vs Planck with gamma lensed]]
</gallery>
Figure 6: Comparison of unlensed and lensed Websky bispectra with Planck measurements. Points are computed at the same set of central <math>\ell</math> values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to Planck values.

Lensed cib

2024-08-14T20:14:38Z

Njcarlson: /* Supplementary Figures */ adding figures

On this page you will find simulation products and supplementary figures to accompany the paper [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

= Simulation Products =

Unlensed CIB mocks from this work can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/unlensed here], and lensed CIB mocks can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/lensed here].


= Supplementary Figures =

<gallery mode="packed-hover" heights="500px">
File:slice_lensing_vFeb2024.png | [[Media:slice_lensing_vFeb2024.png|Slice Lensing]]
</gallery>
Figure 1: CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell (<math>\Delta z = 0.2</math>) within our Websky CIB model. The CIB intensity increases from <math>z = 0</math> to <math>z = 1.4</math>, peaks around <math>z = 1.4</math> to <math>1.6</math>, then decreases until it is almost non-existent by <math>z = 4</math>. The lensing kernels, defined as <math>W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big]</math> with <math>z_i^{\text{src}}</math> being the midpoint of each redshift shell in <math>z</math>-space, typically peak around half of its extent, although they display some skew towards where the CIB intensity is highest, especially as we integrate over more redshifts. The RMS deflection steeply increases at first from <math>0.34~\mathrm{arcmin}</math> for the first lensed shell, up to <math>1.7~\mathrm{arcmin}</math> for the last shell.

<gallery mode="packed-hover" heights="500px">
File:deck_of_cards_v5.png | [[Media:deck_of_cards_v5.png|Deck of cards]]
</gallery>
Figure 2: A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell <math>\Delta z = 0.2</math>. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the "self-lensing" effect substantially. Note that the CIB intensity visibly thins out by <math>z = 3</math>, while the integrated lensing convergence becomes brighter at higher redshifts.

<gallery mode="packed-hover" heights="500px">
File:animation.gif | [[Media:animation.gif|Animation]]
</gallery>
Figure 3: HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small (<math>0.5^\circ \times 0.5^\circ</math>) patch of sky centered on <math>z = 1.1</math>. Here, a "lensed" galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by comparing the Unlensed and Deflected, and the magnification effect by comparing the Deflected and Lensed.

<gallery mode="packed-hover" heights="500px">
File:Websky_vs_Planck_unlensed_fluxcut_mean_no_err_Feb2024.png | [[Media:Websky_vs_Planck_unlensed_fluxcut_mean_no_err_Feb2024.png|WebSky vs Planck unlensed]]
</gallery>
Figure 4: Statistics of the unlensed CIB maps from the Websky simulations at the three Planck frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at <math>\ell > 1000</math>. We note that the Websky bispectra are mostly within Planck error bars even though only the power spectra were fit to match those of Planck's. While we do not plot the error bars for Websky values as there is only one realization, one can estimate the level of uncertainty from the scatter especially for the bispectra and kurtosis.

<gallery mode="packed-hover" heights="500px">
File:unlensed_vs_no_kapmax_with_gamma_smoothed_all_freq_fluxcut_Planck_mean_Feb2024.png | [[Media:unlensed_vs_no_kapmax_with_gamma_smoothed_all_freq_fluxcut_Planck_mean_Feb2024.png|WebSky unlensed vs no kapmax with sigma smoothed]]
</gallery>
Figure 5: The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2% for all three frequencies, the bispectra and kurtosis change by 10 to 40% at low <math>\ell</math>. The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for Planck at lower frequencies.

<gallery mode="packed-hover" heights="500px">
File:Websky_vs_Planck_with_gamma_lensed_bl_all_ebars_Feb2024.png | [[Media:Websky_vs_Planck_with_gamma_lensed_bl_all_ebars_Feb2024.png|Websky vs Planck with gamma lensed]]
</gallery>
Figure 6: Comparison of unlensed and lensed Websky bispectra with Planck measurements. Points are computed at the same set of central <math>\ell</math> values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to Planck values.

Lensed cib

2024-08-14T20:09:16Z

Njcarlson: /* Supplementary Figures */ testing pictures

On this page you will find simulation products and supplementary figures to accompany the paper [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

= Simulation Products =

Unlensed CIB mocks from this work can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/unlensed here], and lensed CIB mocks can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/lensed here].


= Supplementary Figures =

[[Image:slice_lensing_vFeb2024.png|frameless|upright=1.11|right|alt=The Wikipedia logo, with a big blue arrow leading to the Wikimedia Commons logo]]

<gallery mode="packed-hover" heights="500px">
File:slice_lensing_vFeb2024.png | [[Media:slice_lensing_vFeb2024.png|Slice Lensing]]
</gallery>

[slice_lensing]

CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell (<math>\Delta z = 0.2</math>) within our Websky CIB model. The CIB intensity increases from <math>z = 0</math> to <math>z = 1.4</math>, peaks around <math>z = 1.4</math> to <math>1.6</math>, then decreases until it is almost non-existent by <math>z = 4</math>. The lensing kernels, defined as <math>W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big]</math> with <math>z_i^{\text{src}}</math> being the midpoint of each redshift shell in <math>z</math>-space, typically peak around half of its extent, although they display some skew towards where the CIB intensity is highest, especially as we integrate over more redshifts. The RMS deflection steeply increases at first from <math>0.34~\mathrm{arcmin}</math> for the first lensed shell, up to <math>1.7~\mathrm{arcmin}</math> for the last shell.

[deck_of_cards]

A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell <math>\Delta z = 0.2</math>. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the "self-lensing" effect substantially. Note that the CIB intensity visibly thins out by <math>z = 3</math>, while the integrated lensing convergence becomes brighter at higher redshifts.

[animation]

HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small (<math>0.5^\circ \times 0.5^\circ</math>) patch of sky centered on <math>z = 1.1</math>. Here, a "lensed" galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by comparing the Unlensed and Deflected, and the magnification effect by comparing the Deflected and Lensed.

[Websky_vs_Planck_unlensed]

Statistics of the unlensed CIB maps from the Websky simulations at the three Planck frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at <math>\ell > 1000</math>. We note that the Websky bispectra are mostly within Planck error bars even though only the power spectra were fit to match those of Planck's. While we do not plot the error bars for Websky values as there is only one realization, one can estimate the level of uncertainty from the scatter especially for the bispectra and kurtosis.

[unlensed_vs_no_kapmax_with_gamma_...]

The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2% for all three frequencies, the bispectra and kurtosis change by 10 to 40% at low <math>\ell</math>. The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for Planck at lower frequencies.

[Websky_vs_Planck_with_gamma_lensed_bl]

Comparison of unlensed and lensed Websky bispectra with Planck measurements. Points are computed at the same set of central <math>\ell</math> values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to Planck values.

File:Websky vs Planck with gamma lensed bl all ebars Feb2024.png

2024-08-14T19:52:39Z

Njcarlson: Comparison of unlensed and lensed Websky bispectra with \textit{Planck} measurements. Points are computed at the same set of central $\ell$ values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to \textit{Planck} values.

== Summary ==
Comparison of unlensed and lensed Websky bispectra with \textit{Planck} measurements. Points are computed at the same set of central $\ell$ values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to \textit{Planck} values.

File:Unlensed vs no kapmax with gamma smoothed all freq fluxcut Planck mean Feb2024.png

2024-08-14T19:52:15Z

Njcarlson: The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2\% for all three frequencies, the bispectra and kurtosis change by 10 to 40\% at low $\ell.$ The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for \textit{Planck} at lower frequencies.

== Summary ==
The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2\% for all three frequencies, the bispectra and kurtosis change by 10 to 40\% at low $\ell.$ The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for \textit{Planck} at lower frequencies.

File:Websky vs Planck unlensed fluxcut mean no err Feb2024.png

2024-08-14T19:52:00Z

Njcarlson: Statistics of the unlensed CIB maps from the Websky simulations at the three \textit{Planck} frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at $\ell > 1000$. We note that the Websky bispectra are mostly within \textit{Planck} error bars even though only the power spectra were fit to match those of \textit{Planck's}. While we do not plot the error...

== Summary ==
Statistics of the unlensed CIB maps from the Websky simulations at the three \textit{Planck} frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at $\ell > 1000$. We note that the Websky bispectra are mostly within \textit{Planck} error bars even though only the power spectra were fit to match those of \textit{Planck's}. While we do not plot the error bars for Websky values as there is only one realization, one can estimate the level of uncertainty from the scatter especially for the bispectra and kurtosis.

File:Animation.gif

2024-08-14T19:50:12Z

Njcarlson: HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small ($0.5^\circ \times 0.5^\circ$) patch of sky centered on $z = 1.1$. Here, a ``lensed'' galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by c...

== Summary ==
HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small ($0.5^\circ \times 0.5^\circ$) patch of sky centered on $z = 1.1$. Here, a ``lensed'' galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by comparing the Unlensed and Deflected, and the magnification effect by comparing the Deflected and Lensed.

File:Deck of cards v5.png

2024-08-14T19:49:42Z

Njcarlson: A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell $\Delta z = 0.2$. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the `self-lensing' effect substantially. Note that the CIB intensity visibly thins out by $z = 3$, while the integrated lensing convergence becomes brighter at higher redshifts.

== Summary ==
A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell $\Delta z = 0.2$. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the `self-lensing' effect substantially. Note that the CIB intensity visibly thins out by $z = 3$, while the integrated lensing convergence becomes brighter at higher redshifts.

File:Slice lensing vFeb2024.png

2024-08-14T19:49:04Z

Njcarlson: CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell ($\Delta z = 0.2$) within our Websky CIB model. The CIB intensity increases from $z = 0$ to $z = 1.4$, peaks around $z = 1.4$ to $1.6$, then decreases until it is almost non-existent by $z = 4$. The lensing kernels, defined as $W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big...

== Summary ==
CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell ($\Delta z = 0.2$) within our Websky CIB model. The CIB intensity increases from $z = 0$ to $z = 1.4$, peaks around $z = 1.4$ to $1.6$, then decreases until it is almost non-existent by $z = 4$. The lensing kernels, defined as $W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big]$ with $z_i^{\text{src}}$ being the midpoint of each redshift shell in $z$-space, typically peak around half of its extent, although they display some skew towards where the CIB intensity is highest, especially as we integrate over more redshifts. The RMS deflection steeply increases at first from $0.34\arcmin$ for the first lensed shell, up to $1.7\arcmin$ for the last shell.

Lensed cib

2024-08-14T19:06:42Z

Njcarlson: /* Supplementary Figures */ adding figure captions

On this page you will find simulation products and supplementary figures to accompany the paper [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

= Simulation Products =

Unlensed CIB mocks from this work can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/unlensed here], and lensed CIB mocks can be accessed [http://mocks.cita.utoronto.ca/data/lensed_cib/lensed here].


= Supplementary Figures =

[slice_lensing]

CIB intensity, the corresponding lensing potential kernels, as well as the RMS deflection for each redshift shell (<math>\Delta z = 0.2</math>) within our Websky CIB model. The CIB intensity increases from <math>z = 0</math> to <math>z = 1.4</math>, peaks around <math>z = 1.4</math> to <math>1.6</math>, then decreases until it is almost non-existent by <math>z = 4</math>. The lensing kernels, defined as <math>W_{z_i^{\text{src}}}^{\kappa} = \frac{3}{2} \Omega_m H_0 ^2 \frac{1+z}{H(z)}\chi(z) \big[ \frac{\chi(z_i^{\text{src}})-\chi(z)}{\chi(z_i^{\text{src}})}\big]</math> with <math>z_i^{\text{src}}</math> being the midpoint of each redshift shell in <math>z</math>-space, typically peak around half of its extent, although they display some skew towards where the CIB intensity is highest, especially as we integrate over more redshifts. The RMS deflection steeply increases at first from <math>0.34~\mathrm{arcmin}</math> for the first lensed shell, up to <math>1.7~\mathrm{arcmin}</math> for the last shell.

[deck_of_cards]

A patch of unlensed CIB and its corresponding lensing convergence for each redshift shell <math>\Delta z = 0.2</math>. In our simulations, each unlensed CIB shell is lensed by a convergence shell to create lensed CIB shells, which are then summed up to produce the total lensed CIB map. This method mitigates the "self-lensing" effect substantially. Note that the CIB intensity visibly thins out by <math>z = 3</math>, while the integrated lensing convergence becomes brighter at higher redshifts.

[animation]

HealPix maps of unlensed, deflected (no magnification), and lensed CIB for a small (<math>0.5^\circ \times 0.5^\circ</math>) patch of sky centered on <math>z = 1.1</math>. Here, a "lensed" galaxy has both been deflected and has had its flux density magnified appropriately. The arrows denote the direction and magnitude of deflection. The light circled patch (Unlensed and Deflected) and the dark circled patch (Deflected and Lensed) are the same small patch of sky emphasized. One can clearly see the deflection by comparing the Unlensed and Deflected, and the magnification effect by comparing the Deflected and Lensed.

[Websky_vs_Planck_unlensed]

Statistics of the unlensed CIB maps from the Websky simulations at the three Planck frequencies; top (blue) is 545 GHz, middle (green) is 353 GHz, and bottom (red) is 217 GHz. As we go to higher-order statistics, the Poisson regime becomes more evident as the spectra flatten out at <math>\ell > 1000</math>. We note that the Websky bispectra are mostly within Planck error bars even though only the power spectra were fit to match those of Planck's. While we do not plot the error bars for Websky values as there is only one realization, one can estimate the level of uncertainty from the scatter especially for the bispectra and kurtosis.

[unlensed_vs_no_kapmax_with_gamma_...]

The effect of gravitational lensing on CIB statistics using lensing convergence maps smoothed at the pixel level. While the power spectra are changed by less than 2% for all three frequencies, the bispectra and kurtosis change by 10 to 40% at low <math>\ell</math>. The apparent discrepancy between frequencies for the bispectra and kurtosis arises due to the relatively high flux cut values for Planck at lower frequencies.

[Websky_vs_Planck_with_gamma_lensed_bl]

Comparison of unlensed and lensed Websky bispectra with Planck measurements. Points are computed at the same set of central <math>\ell</math> values but are horizontally offset for clarity. The lensed values are slightly larger than unlensed values and hence closer to Planck values.

Lensed cib

2024-08-14T18:58:14Z

Njcarlson: /* Simulation Products */ adding links to lensed CIB simulation products on CITA servers

WebSky Extragalactic CMB Mocks

2024-08-14T18:36:36Z

Njcarlson: /* Data */ adding comment pointing to where the sims are saved

<gallery mode="packed-hover" heights="300px">
File:montage.png | [[Media:montage.png|Websky maps]]
File:Lightcone_60arcmin_300dpi.png | [[Media:Lightcone_60arcmin_300dpi.png | Websky halos ]]

</gallery>

Provided are [https://healpix.jpl.nasa.gov/ HEALPix] .fits files over the full sky at nside=4096 of CIB (in MJy/sr) intensity, Compton-y, kSZ (mu K), CMB lensing convergence, and lensed and un-lensed CMB TT, EE, and BB maps, all from the same 12288^3 particle, 15.4 Gpc peak-patch and 2LPT based cosmological simulation, as well as the light cone halo catalog itself. The minimum halo mass used was ~1.4e12 M200,M. Higher resolution maps and different frequencies are available upon request. For a full description of the contents of these maps see ''The Websky Extragalactic CMB Simulations'' - https://arxiv.org/abs/2001.08787.

= Data =
Data, including [http://mocks.cita.utoronto.ca/data/websky/v0.0 README], available [http://mocks.cita.utoronto.ca/data/websky/v0.0 here]


= Figures =
<gallery mode="packed-hover" heights="250px">
File:tsz.png | [[Media:tsz.png | tSZ power spectrum ]]
File:ksz.png | [[Media:ksz.png | kSZ power spectrum ]]
File:cib.png | [[Media:cib.png | CIB power spectra ]]
File:KappaPower.png | [[Media:KappaPower.png | Convergence power spectrum ]]
File:conversion_factors.png | [[Media:conversion_factors.png | Conversion factors from native maps to delta Tcmb]]
</gallery>

= Acknowledgments =
The WebSky Extragalactic CMB Mocks Collaboration consists of George Stein, Marcelo Alvarez, Dick Bond, Alex van Engelen, Nick Battaglia, and Zack Li, with additional contributions from Amir Hajian.

In order to properly acknowledge our efforts, we request the following paragraph to be included in the “Acknowledgements” section of any publication
which makes use of the simulation data above, and ask you to cite the following papers:

Paper 2: ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020). https://arxiv.org/abs/2001.08787

Paper 1: ''The mass-Peak Patch algorithm for fast generation of deep all-sky dark matter halo catalogues and its N-Body validation'' - G. Stein, M. A. Alvarez, J. R. Bond (2019). https://arxiv.org/abs/1810.07727

"The sky simulations used in this paper were developed by the WebSky Extragalactic CMB Mocks team, with the continuous support of the Canadian Institute for Theoretical Astrophysics (CITA), the Canadian Institute for Advanced Research (CIFAR), and the Natural Sciences and Engineering Council of Canada (NSERC), and were generated on the Niagara supercomputer at the SciNet HPC Consortium (cite https://arxiv.org/abs/1907.13600). SciNet is funded by: the Canada Foundation for Innovation under the auspices of Compute Canada; the Government of Ontario; Ontario Research Fund - Research Excellence; and the University of Toronto."

[[ Documentation | Internal Pages ]]

Lensed cib

2024-08-14T18:30:38Z

Njcarlson:

Large Scale Structure Mocks

2024-07-04T17:41:29Z

Njcarlson: /* Patchy kSZ Maps */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

=== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ===
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2024-07-04T17:41:18Z

Njcarlson: /* WebSky Extragalactic CMB Mocks */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

=== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ===
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ==
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2024-07-04T17:41:11Z

Njcarlson: /* Lensed CIB Mocks */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

=== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ===
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ==
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ==
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Large Scale Structure Mocks

2024-07-04T17:39:56Z

Njcarlson: adding some internal links

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_Peak_Patch_simulations Peak Patch] and [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky#The_WebSky_simulations WebSky], being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ==
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ==
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ==
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Lensed cib

2024-07-04T17:37:55Z

Njcarlson: Created page with "Simulation products coming soon."

Simulation products coming soon.

Large Scale Structure Mocks

2024-06-30T22:17:30Z

Njcarlson: /* Peak Patch and WebSky: How our simulations work */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, Peak Patch and WebSky, being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=[https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky Peak Patch and WebSky: How our simulations work]=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Follow the link in the section heading to read more about the simulations.

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ==
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ==
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ==
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]

Peak Patch and WebSky

2024-06-30T22:13:35Z

Njcarlson: removing flag that the page is under construction because it's mostly done

The Peak Patch and WebSky simulations are a highly efficient tool for modelling the [https://en.wikipedia.org/wiki/Observable_universe#Large-scale_structure large-scale structure] of the universe.

=The Peak Patch simulations=
The Peak Patch simulations[1,2,3] model the distribution of dark matter (DM) in the universe by mapping out catalogues of [https://en.wikipedia.org/wiki/Dark_matter_halo DM halos]. While observations do support halos of DM surrounding most galaxies and clusters, these structures do not have well defined boundaries, so in simulations we must make a choice of where we define the edge of the halo. Typically what is done is to choose the [https://en.wikipedia.org/wiki/Virial_mass#Virial_radius virial radius] within which DM particles are gravitationally bound. In <math>\Lambda</math>CDM cosmology, this corresponds to a halo with an average density about <math>\Delta_c=179</math> times the mean matter density of the universe. Since this is subject to changes in the model parameters, a factor <math>\Delta_c=200</math> is conventionally used, so we do the same.

For the most up-to date description of the Peak Patch algorithm for identifying DM halos, see [https://arxiv.org/abs/1810.07727 arXiv:1810.07727] [4].

For a summary of the Peak Patch algorithm:

# Generate <math>\delta_L(\mathbf{x})</math> field: as initial conditions, Peak Patch uses a linear-theory matter overdensity field <math>\delta_L(\mathbf{x})</math>, which is the matter overdensity <math>\delta(\mathbf{x}) = \rho_m(\mathbf{x},t) / \bar{\rho}_m(t) - 1</math> at a time <math>t</math> sufficiently early in the history of the universe that linear theory is a suitable approximation to the dynamics that formed it. <math>\delta_L(\mathbf{x})</math> can either by read from a file or generated from a [https://en.wikipedia.org/wiki/Matter_power_spectrum power spectrum] (which describe the number of structures of different sizes that we observe in the universe).
# Smooth and find peaks: the <math>\delta_L(\mathbf{x})</math> field is then smoothed at a series of scales by convolving with top hat functions (e.g. see section 3.2 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]). This removes any fluctuations smaller than about the top-hat function's cutoff radius <math>R_\mathrm{th}</math> allowing us to isolate just structures in <math>\delta_L(\mathbf{x})</math> larger than <math>R_\mathrm{th}</math>. Peaks in each filtered density field are found, these are candidate sites where dark matter halos may form.
# Ellipsoidal collapse: dark matter halos are gravitationally bound collections of dark matter, and therefore [https://en.wikipedia.org/wiki/Virial_theorem#Dark_matter virialised]. To determine if a given peak will collapse to form a virialised halo, we model it as a uniform-density sphere of radius <math>R_\mathrm{th}</math> (the top-hat filter radius at which the peak was identified), and allow it to collapse ellipsoidally (e.g. see section 3.3 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]) subject to the local strain of the <math>\delta_L(\mathbf{x})</math> field. If the collapse has enough time to reach a density contrast characteristic of virialised structure by time <math>t</math>, it is saved as a candidate halo of radius <math>R_\mathrm{th}</math>, or mass <math>M = \bar{\rho}_{m}(t_0) \frac{4}{3} \pi R_\mathrm{th}^3</math>.Peak Patch can either produce single-redshift simulations, where all halos collapse until the same time <math>t</math>, or light cone simulations where each halo is evolved only until the age it appears to be at relative to a specified observer (so <math>t</math> is the light travel time to the halo). The latter is ideal for making sky maps.
# Merging and exclusion: because halo candidates are found at multiple filter scales, overlaps are inevitable. So a merging and exclusion algorithm is run with any halo entirely inside another being tossed out and halos overlapping regions partially allotted to each halo to avoid double counting mass.
# Displacement to final state halos: up to this point, we have been working in Lagrangian space, essentially determining what mass in the initial conditions fields will form halos. But as matter collapses into halos, these halos will also move relative to one another. Most of the highly nonlinear dynamics occurs within DM halos, so the displacement of the halos themselves can be accomplished with 2nd order Lagrangian perturbation theory.

The DM halo catalogues generated by Peak Patch have been validated by <math>N</math>-body simulations[4], achieving similar results with much greater computational efficiency. Peak Patch has performed favourably compared to other halo-finders[5,6,7].

Peak Patch is additionally a particularly powerful tool for studying beyond-standard-model (BSM) cosmologies because the simulation has built-in support for varying <math>\Lambda</math>CDM model parameters and [https://en.wikipedia.org/wiki/Non-Gaussianity primordial non-Gaussianities] of a number of forms informed by a range of early-universe physics phenomena. Because it employs only approximate dynamics, complete knowledge of the BSM equations of motion is not required, allowing us to probe wider parameter space.

Coupled with WebSky, Peak Patch light-cone runs can be used to generate mock sky maps for observatories and have been used extensively by ACT in recent years to make CMB foreground mock maps. The WebSky algorithm is summarised in the next section.

=The WebSky simulations=
The WebSky[8] simulations produce mock sky maps from DM halo catalogues in a range of observables. Mock sky maps are simulated maps of the sky that are statistically analogous to maps of the sky made by observatories. They don't reproduce our particular universe, but they produce one with the same statistics meaning that you will not have galaxies in the exact same locations as the universe as we observe it, but statistical measures such as correlation functions and probability density functions will be reproduced.

The WebSky algorithm translates a light-cone DM halo catalogue to a map of the sky. Light-cone runs have a specified observer position, so mapping is done by calculating an accumulated signal from all the halos along a given line of sight. The signal from each halo, or response function, is based on an assumption of a spherically symmetric pressure profile[9,10,11,12] (which we refer to as a "BBPS" profile after the authors). Each response function is then built from up to three components
* a halo contribution: for signals that are proportional to DM halo density, the halo contribution relates the BBPS pressure profile to the response in an observable.
* a field contribution: for signals that are affected by the exterior of the halo, not just the dense virialised core, an extension to the BBPS profile is used.
* a halo occupation distribution (HOD) model: for signals that are affected by point-source emission from galactic centres, a HOD model is used. In this model, there is assumed to be a large central galaxy in each halo, larger halos then also have a series of satellite galaxies randomly distributed around it with a PDF related to the BBPS profile.

Currently, supported WebSky response functions are:
* [https://en.wikipedia.org/wiki/Sunyaev%E2%80%93Zeldovich_effect Sunyaev Zel'dovich (SZ) effects]
** thermal Sunyaev Zel'dovich (tSZ) effect caused by scattering of CMB photons by electrons in hot gas clouds
** kinetic/kinematic Sunyaev Zel'dovich (kSZ) effect caused by scattering of CMB photons by electrons in bulk flows of gas
* weak gravitational lensing [https://en.wikipedia.org/wiki/Gravitational_lensing_formalism#Convergence_and_deflection_potential convergence maps] defining the amount of magnification caused by weak gravitational lensing by galaxy clusters
* [https://en.wikipedia.org/wiki/Cosmic_infrared_background cosmic infrared background] maps showing the emission of infrared photons from dusty star forming regions
* [https://en.wikipedia.org/wiki/Intensity_mapping line intensity maps]
** HI 21 cm line emission from a hyperfine electron spin flip transition in neutral hydrogen producing a photon with a wavelength of about 21 cm. 21 cm emission could provide a tantalising glimpse into the [https://en.wikipedia.org/wiki/Reionization epoch of reionisation] and the formation of the first strs.
** CII emission line at <math>\nu=1897\text{ GHz}</math> from a fine structure transition in singly ionised carbon
** CO(1-0) line emission from carbon monoxide based on a model by Li, et al. 2016[13]
** CO(2-1) line emission from carbon monoxide based on a model by Zack Li, Dongwoo Chung, et al. in prep.

For the most up to date description of WebSky, see the paper [https://arxiv.org/abs/2001.08787 arXiv:2001.08787][8], and stay tuned for the release of WebSky2.0, which will feature fully lensed maps generated from a suite of primordial non-Gaussianity models.

=Notes=
1. WebSky has two pronunciations wɛbskaɪ and wɛbskiː which are understood to exist in superposition
<math> | \text{WEB} \rangle \otimes \left( \frac{ | \text{sky} \rangle + | \text{skee} \rangle }{ \sqrt{2} } \right) </math>.

=References=
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. I. Algorithms", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103....1B/abstract 1996ApJS..103....1B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. II. Validation", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...41B/abstract 1996ApJS..103...41B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. III. Application to Clusters", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...63B/abstract 1996ApJS..103...63B].
# Stein, G., Alvarez, M. A. and Bond, J. R. (2018) "The mass-Peak Patch algorithm for fast generation of deep all-sky dark matter halo catalogues and its N-Body validation", [https://arxiv.org/abs/1810.07727 arXiv:1810.07727].
# Lippich, M., et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices - I. Correlation function", [https://arxiv.org/abs/1806.09477 arXiv:1806.09477].
# Blot, L. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices II: Power spectrum multipoles", [https://arxiv.org/abs/1806.09497 arXiv:1806.09497].
# Colavincenzo, M. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices III: Bispectrum", [https://arxiv.org/abs/1806.09499 arXiv:1806.09499].
# Stein, G., Alvarez, M. A., Bond, J. R., van Engelen, A. and Battaglia, N. (2020) "The Websky Extragalactic CMB Simulations", [https://arxiv.org/abs/2001.08787 arXiv:2001.08787].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. I. The Influence of Feedback, Non-thermal Pressure, and Cluster Shapes on Y-M Scaling Relations", [https://arxiv.org/abs/1109.3709 arXiv:1109.3709].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich Surveys II: Deconstructing the Thermal SZ Power Spectrum", [https://arxiv.org/abs/1109.3711 arXiv:1109.3711].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2013) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. III. Measurement Biases and Cosmological Evolution of Gas and Stellar Mass Fractions", [https://arxiv.org/abs/1209.4082 arXiv:1209.4082].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2015) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. IV. Characterizing Density and Pressure Clumping due to Infalling Substructures", [https://arxiv.org/abs/1405.3346 arXiv:1405.3346].
# Li, T. Y., Wechsler, R. H., Devaraj, K. and Church, S. E. (2015) "Connecting CO Intensity Mapping to Molecular Gas and Star Formation in the Epoch of Galaxy Assembly", [https://arxiv.org/abs/1503.08833 arXiv:1503.08833]

Peak Patch and WebSky

2024-06-30T22:13:09Z

Njcarlson: /* References */ adding li model to refs

[ Note this page is under construction ]

The Peak Patch and WebSky simulations are a highly efficient tool for modelling the [https://en.wikipedia.org/wiki/Observable_universe#Large-scale_structure large-scale structure] of the universe.

=The Peak Patch simulations=
The Peak Patch simulations[1,2,3] model the distribution of dark matter (DM) in the universe by mapping out catalogues of [https://en.wikipedia.org/wiki/Dark_matter_halo DM halos]. While observations do support halos of DM surrounding most galaxies and clusters, these structures do not have well defined boundaries, so in simulations we must make a choice of where we define the edge of the halo. Typically what is done is to choose the [https://en.wikipedia.org/wiki/Virial_mass#Virial_radius virial radius] within which DM particles are gravitationally bound. In <math>\Lambda</math>CDM cosmology, this corresponds to a halo with an average density about <math>\Delta_c=179</math> times the mean matter density of the universe. Since this is subject to changes in the model parameters, a factor <math>\Delta_c=200</math> is conventionally used, so we do the same.

For the most up-to date description of the Peak Patch algorithm for identifying DM halos, see [https://arxiv.org/abs/1810.07727 arXiv:1810.07727] [4].

For a summary of the Peak Patch algorithm:

# Generate <math>\delta_L(\mathbf{x})</math> field: as initial conditions, Peak Patch uses a linear-theory matter overdensity field <math>\delta_L(\mathbf{x})</math>, which is the matter overdensity <math>\delta(\mathbf{x}) = \rho_m(\mathbf{x},t) / \bar{\rho}_m(t) - 1</math> at a time <math>t</math> sufficiently early in the history of the universe that linear theory is a suitable approximation to the dynamics that formed it. <math>\delta_L(\mathbf{x})</math> can either by read from a file or generated from a [https://en.wikipedia.org/wiki/Matter_power_spectrum power spectrum] (which describe the number of structures of different sizes that we observe in the universe).
# Smooth and find peaks: the <math>\delta_L(\mathbf{x})</math> field is then smoothed at a series of scales by convolving with top hat functions (e.g. see section 3.2 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]). This removes any fluctuations smaller than about the top-hat function's cutoff radius <math>R_\mathrm{th}</math> allowing us to isolate just structures in <math>\delta_L(\mathbf{x})</math> larger than <math>R_\mathrm{th}</math>. Peaks in each filtered density field are found, these are candidate sites where dark matter halos may form.
# Ellipsoidal collapse: dark matter halos are gravitationally bound collections of dark matter, and therefore [https://en.wikipedia.org/wiki/Virial_theorem#Dark_matter virialised]. To determine if a given peak will collapse to form a virialised halo, we model it as a uniform-density sphere of radius <math>R_\mathrm{th}</math> (the top-hat filter radius at which the peak was identified), and allow it to collapse ellipsoidally (e.g. see section 3.3 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]) subject to the local strain of the <math>\delta_L(\mathbf{x})</math> field. If the collapse has enough time to reach a density contrast characteristic of virialised structure by time <math>t</math>, it is saved as a candidate halo of radius <math>R_\mathrm{th}</math>, or mass <math>M = \bar{\rho}_{m}(t_0) \frac{4}{3} \pi R_\mathrm{th}^3</math>.Peak Patch can either produce single-redshift simulations, where all halos collapse until the same time <math>t</math>, or light cone simulations where each halo is evolved only until the age it appears to be at relative to a specified observer (so <math>t</math> is the light travel time to the halo). The latter is ideal for making sky maps.
# Merging and exclusion: because halo candidates are found at multiple filter scales, overlaps are inevitable. So a merging and exclusion algorithm is run with any halo entirely inside another being tossed out and halos overlapping regions partially allotted to each halo to avoid double counting mass.
# Displacement to final state halos: up to this point, we have been working in Lagrangian space, essentially determining what mass in the initial conditions fields will form halos. But as matter collapses into halos, these halos will also move relative to one another. Most of the highly nonlinear dynamics occurs within DM halos, so the displacement of the halos themselves can be accomplished with 2nd order Lagrangian perturbation theory.

The DM halo catalogues generated by Peak Patch have been validated by <math>N</math>-body simulations[4], achieving similar results with much greater computational efficiency. Peak Patch has performed favourably compared to other halo-finders[5,6,7].

Peak Patch is additionally a particularly powerful tool for studying beyond-standard-model (BSM) cosmologies because the simulation has built-in support for varying <math>\Lambda</math>CDM model parameters and [https://en.wikipedia.org/wiki/Non-Gaussianity primordial non-Gaussianities] of a number of forms informed by a range of early-universe physics phenomena. Because it employs only approximate dynamics, complete knowledge of the BSM equations of motion is not required, allowing us to probe wider parameter space.

Coupled with WebSky, Peak Patch light-cone runs can be used to generate mock sky maps for observatories and have been used extensively by ACT in recent years to make CMB foreground mock maps. The WebSky algorithm is summarised in the next section.

=The WebSky simulations=
The WebSky[8] simulations produce mock sky maps from DM halo catalogues in a range of observables. Mock sky maps are simulated maps of the sky that are statistically analogous to maps of the sky made by observatories. They don't reproduce our particular universe, but they produce one with the same statistics meaning that you will not have galaxies in the exact same locations as the universe as we observe it, but statistical measures such as correlation functions and probability density functions will be reproduced.

The WebSky algorithm translates a light-cone DM halo catalogue to a map of the sky. Light-cone runs have a specified observer position, so mapping is done by calculating an accumulated signal from all the halos along a given line of sight. The signal from each halo, or response function, is based on an assumption of a spherically symmetric pressure profile[9,10,11,12] (which we refer to as a "BBPS" profile after the authors). Each response function is then built from up to three components
* a halo contribution: for signals that are proportional to DM halo density, the halo contribution relates the BBPS pressure profile to the response in an observable.
* a field contribution: for signals that are affected by the exterior of the halo, not just the dense virialised core, an extension to the BBPS profile is used.
* a halo occupation distribution (HOD) model: for signals that are affected by point-source emission from galactic centres, a HOD model is used. In this model, there is assumed to be a large central galaxy in each halo, larger halos then also have a series of satellite galaxies randomly distributed around it with a PDF related to the BBPS profile.

Currently, supported WebSky response functions are:
* [https://en.wikipedia.org/wiki/Sunyaev%E2%80%93Zeldovich_effect Sunyaev Zel'dovich (SZ) effects]
** thermal Sunyaev Zel'dovich (tSZ) effect caused by scattering of CMB photons by electrons in hot gas clouds
** kinetic/kinematic Sunyaev Zel'dovich (kSZ) effect caused by scattering of CMB photons by electrons in bulk flows of gas
* weak gravitational lensing [https://en.wikipedia.org/wiki/Gravitational_lensing_formalism#Convergence_and_deflection_potential convergence maps] defining the amount of magnification caused by weak gravitational lensing by galaxy clusters
* [https://en.wikipedia.org/wiki/Cosmic_infrared_background cosmic infrared background] maps showing the emission of infrared photons from dusty star forming regions
* [https://en.wikipedia.org/wiki/Intensity_mapping line intensity maps]
** HI 21 cm line emission from a hyperfine electron spin flip transition in neutral hydrogen producing a photon with a wavelength of about 21 cm. 21 cm emission could provide a tantalising glimpse into the [https://en.wikipedia.org/wiki/Reionization epoch of reionisation] and the formation of the first strs.
** CII emission line at <math>\nu=1897\text{ GHz}</math> from a fine structure transition in singly ionised carbon
** CO(1-0) line emission from carbon monoxide based on a model by Li, et al. 2016[13]
** CO(2-1) line emission from carbon monoxide based on a model by Zack Li, Dongwoo Chung, et al. in prep.

For the most up to date description of WebSky, see the paper [https://arxiv.org/abs/2001.08787 arXiv:2001.08787][8], and stay tuned for the release of WebSky2.0, which will feature fully lensed maps generated from a suite of primordial non-Gaussianity models.

=Notes=
1. WebSky has two pronunciations wɛbskaɪ and wɛbskiː which are understood to exist in superposition
<math> | \text{WEB} \rangle \otimes \left( \frac{ | \text{sky} \rangle + | \text{skee} \rangle }{ \sqrt{2} } \right) </math>.

=References=
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. I. Algorithms", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103....1B/abstract 1996ApJS..103....1B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. II. Validation", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...41B/abstract 1996ApJS..103...41B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. III. Application to Clusters", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...63B/abstract 1996ApJS..103...63B].
# Stein, G., Alvarez, M. A. and Bond, J. R. (2018) "The mass-Peak Patch algorithm for fast generation of deep all-sky dark matter halo catalogues and its N-Body validation", [https://arxiv.org/abs/1810.07727 arXiv:1810.07727].
# Lippich, M., et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices - I. Correlation function", [https://arxiv.org/abs/1806.09477 arXiv:1806.09477].
# Blot, L. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices II: Power spectrum multipoles", [https://arxiv.org/abs/1806.09497 arXiv:1806.09497].
# Colavincenzo, M. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices III: Bispectrum", [https://arxiv.org/abs/1806.09499 arXiv:1806.09499].
# Stein, G., Alvarez, M. A., Bond, J. R., van Engelen, A. and Battaglia, N. (2020) "The Websky Extragalactic CMB Simulations", [https://arxiv.org/abs/2001.08787 arXiv:2001.08787].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. I. The Influence of Feedback, Non-thermal Pressure, and Cluster Shapes on Y-M Scaling Relations", [https://arxiv.org/abs/1109.3709 arXiv:1109.3709].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich Surveys II: Deconstructing the Thermal SZ Power Spectrum", [https://arxiv.org/abs/1109.3711 arXiv:1109.3711].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2013) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. III. Measurement Biases and Cosmological Evolution of Gas and Stellar Mass Fractions", [https://arxiv.org/abs/1209.4082 arXiv:1209.4082].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2015) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. IV. Characterizing Density and Pressure Clumping due to Infalling Substructures", [https://arxiv.org/abs/1405.3346 arXiv:1405.3346].
# Li, T. Y., Wechsler, R. H., Devaraj, K. and Church, S. E. (2015) "Connecting CO Intensity Mapping to Molecular Gas and Star Formation in the Epoch of Galaxy Assembly", [https://arxiv.org/abs/1503.08833 arXiv:1503.08833]

Peak Patch and WebSky

2024-06-30T22:10:57Z

Njcarlson: /* The WebSky simulations */ adding full description of the websky sims

Peak Patch and WebSky

2024-06-30T19:36:18Z

Njcarlson: /* References */ adding reference to websky and bbps papers

[ Note this page is under construction ]

The Peak Patch and WebSky simulations are a highly efficient tool for modelling the [https://en.wikipedia.org/wiki/Observable_universe#Large-scale_structure large-scale structure] of the universe.

=The Peak Patch simulations=
The Peak Patch simulations[1,2,3] model the distribution of dark matter (DM) in the universe by mapping out catalogues of [https://en.wikipedia.org/wiki/Dark_matter_halo DM halos]. While observations do support halos of DM surrounding most galaxies and clusters, these structures do not have well defined boundaries, so in simulations we must make a choice of where we define the edge of the halo. Typically what is done is to choose the [https://en.wikipedia.org/wiki/Virial_mass#Virial_radius virial radius] within which DM particles are gravitationally bound. In <math>\Lambda</math>CDM cosmology, this corresponds to a halo with an average density about <math>\Delta_c=179</math> times the mean matter density of the universe. Since this is subject to changes in the model parameters, a factor <math>\Delta_c=200</math> is conventionally used, so we do the same.

For the most up-to date description of the Peak Patch algorithm for identifying DM halos, see [https://arxiv.org/abs/1810.07727 arXiv:1810.07727] [4].

For a summary of the Peak Patch algorithm:

# Generate <math>\delta_L(\mathbf{x})</math> field: as initial conditions, Peak Patch uses a linear-theory matter overdensity field <math>\delta_L(\mathbf{x})</math>, which is the matter overdensity <math>\delta(\mathbf{x}) = \rho_m(\mathbf{x},t) / \bar{\rho}_m(t) - 1</math> at a time <math>t</math> sufficiently early in the history of the universe that linear theory is a suitable approximation to the dynamics that formed it. <math>\delta_L(\mathbf{x})</math> can either by read from a file or generated from a [https://en.wikipedia.org/wiki/Matter_power_spectrum power spectrum] (which describe the number of structures of different sizes that we observe in the universe).
# Smooth and find peaks: the <math>\delta_L(\mathbf{x})</math> field is then smoothed at a series of scales by convolving with top hat functions (e.g. see section 3.2 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]). This removes any fluctuations smaller than about the top-hat function's cutoff radius <math>R_\mathrm{th}</math> allowing us to isolate just structures in <math>\delta_L(\mathbf{x})</math> larger than <math>R_\mathrm{th}</math>. Peaks in each filtered density field are found, these are candidate sites where dark matter halos may form.
# Ellipsoidal collapse: dark matter halos are gravitationally bound collections of dark matter, and therefore [https://en.wikipedia.org/wiki/Virial_theorem#Dark_matter virialised]. To determine if a given peak will collapse to form a virialised halo, we model it as a uniform-density sphere of radius <math>R_\mathrm{th}</math> (the top-hat filter radius at which the peak was identified), and allow it to collapse ellipsoidally (e.g. see section 3.3 of [https://www.cita.utoronto.ca/~njcarlson/public/papers/van_de_Weygaert_and_Bond_i.pdf this review article]) subject to the local strain of the <math>\delta_L(\mathbf{x})</math> field. If the collapse has enough time to reach a density contrast characteristic of virialised structure by time <math>t</math>, it is saved as a candidate halo of radius <math>R_\mathrm{th}</math>, or mass <math>M = \bar{\rho}_{m}(t_0) \frac{4}{3} \pi R_\mathrm{th}^3</math>.Peak Patch can either produce single-redshift simulations, where all halos collapse until the same time <math>t</math>, or light cone simulations where each halo is evolved only until the age it appears to be at relative to a specified observer (so <math>t</math> is the light travel time to the halo). The latter is ideal for making sky maps.
# Merging and exclusion: because halo candidates are found at multiple filter scales, overlaps are inevitable. So a merging and exclusion algorithm is run with any halo entirely inside another being tossed out and halos overlapping regions partially allotted to each halo to avoid double counting mass.
# Displacement to final state halos: up to this point, we have been working in Lagrangian space, essentially determining what mass in the initial conditions fields will form halos. But as matter collapses into halos, these halos will also move relative to one another. Most of the highly nonlinear dynamics occurs within DM halos, so the displacement of the halos themselves can be accomplished with 2nd order Lagrangian perturbation theory.

The DM halo catalogues generated by Peak Patch have been validated by <math>N</math>-body simulations[4], achieving similar results with much greater computational efficiency. Peak Patch has performed favourably compared to other halo-finders[5,6,7].

Peak Patch is additionally a particularly powerful tool for studying beyond-standard-model (BSM) cosmologies because the simulation has built-in support for varying <math>\Lambda</math>CDM model parameters and [https://en.wikipedia.org/wiki/Non-Gaussianity primordial non-Gaussianities] of a number of forms informed by a range of early-universe physics phenomena. Because it employs only approximate dynamics, complete knowledge of the BSM equations of motion is not required, allowing us to probe wider parameter space.

Coupled with WebSky, Peak Patch light-cone runs can be used to generate mock sky maps for observatories and have been used extensively by ACT in recent years to make CMB foreground mock maps. The WebSky algorithm is summarised in the next section.

=The WebSky simulations=
The WebSky[8] simulations produce mock sky maps in a range of observables. Mock sky maps are simulated maps of the sky that are statistically analogous to maps of the sky made by observatories.

[ discuss model ]

[ discuss different response functions ]

[ link to paper ]

==Notes==
1. WebSky has two pronunciations wɛbskaɪ and wɛbskiː which are understood to exist in superposition
<math> | \text{WEB} \rangle \otimes \left( \frac{ | \text{sky} \rangle + | \text{skee} \rangle }{ \sqrt{2} } \right) </math>.

=References=
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. I. Algorithms", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103....1B/abstract 1996ApJS..103....1B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. II. Validation", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...41B/abstract 1996ApJS..103...41B].
# Bond, J. R. and Myers, S. T. (1996) "The Peak-Patch Picture of Cosmic Catalogs. III. Application to Clusters", [https://ui.adsabs.harvard.edu/abs/1996ApJS..103...63B/abstract 1996ApJS..103...63B].
# Stein, G., Alvarez, M. A. and Bond, J. R. (2018) "The mass-Peak Patch algorithm for fast generation of deep all-sky dark matter halo catalogues and its N-Body validation", [https://arxiv.org/abs/1810.07727 arXiv:1810.07727].
# Lippich, M., et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices - I. Correlation function", [https://arxiv.org/abs/1806.09477 arXiv:1806.09477].
# Blot, L. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices II: Power spectrum multipoles", [https://arxiv.org/abs/1806.09497 arXiv:1806.09497].
# Colavincenzo, M. et al. (2019) "Comparing approximate methods for mock catalogues and covariance matrices III: Bispectrum", [https://arxiv.org/abs/1806.09499 arXiv:1806.09499].
# Stein, G., Alvarez, M. A., Bond, J. R., van Engelen, A. and Battaglia, N. (2020) "The Websky Extragalactic CMB Simulations", [https://arxiv.org/abs/2001.08787 arXiv:2001.08787].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. I. The Influence of Feedback, Non-thermal Pressure, and Cluster Shapes on Y-M Scaling Relations", [https://arxiv.org/abs/1109.3709 arXiv:1109.3709].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2012) "On the Cluster Physics of Sunyaev-Zel'dovich Surveys II: Deconstructing the Thermal SZ Power Spectrum", [https://arxiv.org/abs/1109.3711 arXiv:1109.3711].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2013) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. III. Measurement Biases and Cosmological Evolution of Gas and Stellar Mass Fractions", [https://arxiv.org/abs/1209.4082 arXiv:1209.4082].
# Battaglia, N., Bond, J. R., Pfrommer, C. and Sievers, J. L. (2015) "On the Cluster Physics of Sunyaev-Zel'dovich and X-Ray Surveys. IV. Characterizing Density and Pressure Clumping due to Infalling Substructures", [https://arxiv.org/abs/1405.3346 arXiv:1405.3346].

Peak Patch and WebSky

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Njcarlson: /* The WebSky simulations */ adding citation for websky paper

Peak Patch and WebSky

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Njcarlson: Adding references for peak patch section

Peak Patch and WebSky

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Njcarlson: /* The Peak Patch simulations */ finishing peak patch section

Peak Patch and WebSky

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Njcarlson: /* The Peak Patch simulations */ filling in details on how the sims work

Peak Patch and WebSky

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Njcarlson: /* Notes */

Peak Patch and WebSky

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Njcarlson: Created page with "[ Note this page is under construction ] The Peak Patch and WebSky simulations are a highly efficient tool for modelling the [https://en.wikipedia.org/wiki/Obse..."

Large Scale Structure Mocks

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Njcarlson: /* Peak Patch and WebSky: How our simulations work */

Welcome to the CITA LSS Mocks Portal. Here you will find information on the large-scale structure cosmological simulations, Peak Patch and WebSky, being developed at CITA, as well as publicly available simulation products from each CITA LSS Mocks Project.

=Peak Patch and WebSky: How our simulations work=
Peak Patch is a robust and highly efficient [https://en.wikipedia.org/wiki/Dark_matter_halo dark matter (DM) halo] finder. WebSky is a sky-map maker that generates mock sky maps using a suite of response functions to Peak Patch DM halo catalogues. Follow the link in the section header to learn more about these codes. Read more about the simulations [https://mocks.cita.utoronto.ca/index.php/Peak_Patch_and_WebSky here].

= Simulation Products =
The following sections link (in reverse chronological order) to the page for each of the publicly released CITA Mocks Projects. These provide information on the respective projects and link to publicly released simulation products. See the linked papers for the full details.

== [https://mocks.cita.utoronto.ca/index.php/lensed_cib Lensed CIB Mocks] ==
Data to accompany [https://arxiv.org/abs/2304.07283 ''Exploring the Non-Gaussianity of the Cosmic Infrared Background and Its Weak Gravitational Lensing'' - J. Lee, J. R. Bond, P. Motloch, A. van Engelen, G. Stein (2024)].

== [http://mocks.cita.utoronto.ca/websky WebSky Extragalactic CMB Mocks] ==
Data to accompany [https://arxiv.org/abs/2001.08787 ''The Websky Extragalactic CMB Simulations'' - G. Stein, M. A. Alvarez, J. R. Bond, A. v. Engelen, N. Battaglia (2020)].

== [http://cita.utoronto.ca/~malvarez/research/ksz-data Patchy kSZ Maps] ==
Data to accompany [https://arxiv.org/abs/1511.02846 ''The Kinetic Sunyaev-Zel’dovich Effect from Reionization: Simulated Full-sky Maps at Arcminute Resolution'' - M. A. Alvarez (2016)]