1/f noise in WMAP 3yr data

Post Reply
carlos monteserin
Posts: 1
Joined: February 08 2007
Affiliation: IFCA (Santander,Spain)

1/f noise in WMAP 3yr data

Post by carlos monteserin » February 08 2007


white noise dispersion maps are approximately sqrt(3) times lower in WMAP coadded 3yr than in single 1yr maps.

somebody knows how much is this factor for the 1/f noise?


Tom Crawford
Posts: 8
Joined: December 29 2004
Affiliation: University of Chicago

1/f noise in WMAP 3yr data

Post by Tom Crawford » February 10 2007

There are only two reasons why the 1/f contributions wouldn't also be [tex]\sqrt{3}[/tex] lower:

1) The amplitude of the 1/f sources changed appreciably over years two and three.

2) The sources of 1/f aren't really noise (i.e., they're coherent in some basis that matters to the instrument), and so they don't integrate down as [tex]\sqrt{N}[/tex].

Given the observed stability of the instrument, I think 1) is unlikely, and 2) is something that I think the WMAP team has checked pretty thoroughly. So I think you're probably safe in assuming that the 1/f scales the same way the white noise does.

(Of course, I'm not on the WMAP team, so there may be something important that I'm missing.)

Post Reply