1607.05406
Galaxy-galaxy weak lensing measurements from SDSS: I. Image processing and lensing signals
Luo, et al
As the first paper in a series on the study of the gg lensing from SDSS DR7, present the image processing pipeline that corrects the systematics primarily introduced by the PSF. Using this pipeline, process SDSS DR7 imaging data in r band and generated a background galaxy catalog containing the shape information of each galaxy. Based on own shape measurements of the galaxy images from SDSS DR7, extract the galaxy-galaxy (GG) lensing signals around foreground spectroscopic galaxies binned in different luminosity and stellar mass. The overall signals are in good agreement with those obtained by Mandelbaum 05, 06 from SDSS DR4. The results in this paper with higher signal to noise ratio is due to the larger survey area than SDSS DR4, confirm that more luminous/massive galaxies bear stronger GG lensing signal. Also divide the foreground galaxies into red/blue and star forming/quenched subsamples and measured their GG lensing signals, respectively. Find that, at a specific stellar mass/luminosity, the red/quenched galaxies have relatively stronger GG lensing signals than their counterparts especially at large radii. These GG lensing signals can be used to probe the galaxy-halo mass relations and their environmental dependences in the halo occupation or conditional luminosity function framework.
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