Cluster Seminar: Subhalo Properties in SDSS DR7 with Galaxy-galaxy Lensing
Date:
This is a talk of cluster seminar of Department of Astronomy, Umich. In this talk, I will focus on our recent work about subhalo properties in Yang et al. (2007) 's group catalog based on SDSS DR7. We devide satellite galaxies into different stellar mass and BCG-center separation bins, then measure the lensing signals around these satellites. We discover an unreported selection effect between separation and host halo mass and use a weighting method to correct it. With a 2 free paramater model to describe excess surface density of subhalo, we fit the weighted lensing signal by MCMC. In this talk, I will first introduce galaxy-galaxy lensing method and subhalo density profile, then talk about the methods and main results of this work.