July 14th, 2019 - CIB Smoothing: Iterations

Yesterday, Pavel mentioned that it is odd that smoothing the CIB with 12" and 5" beams seems to have almost the same effects. Thus, I tried smoothing the two maps with different iterations (healpy.smoothing has a parameter called 'iter', where the number of iterations can be changed).

Histograms (Left: 12", Right: 5")

It is hard to see any difference between the iter = 3 - smoothed maps and iter = 1 - smoothed maps.

Histogram Differences

I tried plotting the differences between the two histograms (iter = 3 - iter = 1)

Histogram Fractional Differences

Here are the fractional differences of the histograms.

While they fluctuate around zero for both, the fractional differences are clearly non-zero and become larger as [math]\displaystyle{ \ell }[/math] increase.

Cartview

1. lon = [0, 0.5], lat = [0, 0.5], min = 0.1, max = 0.8

-12"

-5"

Again, it is impossible to see the difference in the maps with the given parameters.

2. lon = [-75.5, -75], lat = [-75.5, -75], min = 0.3, max = 0.4

-12"

-5"