Monday, January 29, 2007

Lot's of counting

I've been counting the galaxies around the MaxBCG clusters. I decided that while I was at it I might as well count the luminosity. And while I was at it, why just count the galaxies as a function of radius? Why not count them as a function of their other two basic observables, color and luminosity? So I now have this cube of counts as a function of radius, color (g-r) and luminosity, background subtracted and edge corrected. And the same for luminosity.

The original motivation for this was to measure mass-to-light ratios by comparing the excess luminosity to the excess mass from the lensing measurements. But I think this cube is going to yield a lot of science beyond that. I'm writing up the basic measurements and doing statistics like luminosity functions, blue fractions and such. Sarah Hansen is going to move along the lines of here 2005 paper with better S/N. Blanton and Hogg both have some good ideas which will either make it into my paper or separate papers.

P.S. I'm going to start posting regularly again. Seriously.

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