Galaxy halo masses and satellite fractions from galaxy-galaxy lensing in the SDSS: stellar mass, luminosity, morphology, and environment dependencies

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

19 pages, matches MNRAS accepted version

Scientific paper

10.1111/j.1365-2966.2006.10156.x

The relationship between galaxies and dark matter can be characterized by the halo mass of the central galaxy and the fraction of galaxies that are satellites. Here we present observational constraints from the SDSS on these quantities as a function of r-band luminosity and stellar mass using galaxy-galaxy weak lensing, with a total of 351,507 lenses. We use stellar masses derived from spectroscopy and virial halo masses derived from weak gravitational lensing to determine the efficiency with which baryons in the halo of the central galaxy have been converted into stars. We find that an L* galaxy with a stellar mass of 6x10^{10} M_{sun} is hosted by a halo with mass of 1.4x10^{12} M_{sun}/h, independent of morphology, yielding baryon conversion efficiencies of 17_{-5}^{+10} (early types) and 16_{-6}^{+15} (late types) per cent at the 95 per cent CL (statistical, not including systematic uncertainty due to assumption of a universal initial mass function, or IMF). We find that for a given stellar mass, the halo mass is independent of morphology below M_{stellar}=10^{11} M_{sun}, in contrast to typically a factor of two difference in halo mass between ellipticals and spirals at a fixed luminosity. This suggests that stellar mass is a good proxy for halo mass in this range and should be used preferentially whenever a halo mass selected sample is needed. For higher stellar masses, the conversion efficiency is a declining function of stellar mass, and the differences in halo mass between early and late types become larger, reflecting the fact that most group and cluster halos with masses above 10^{13} M_{sun} host ellipticals at the center, while even the brightest central spirals are hosted by halos of mass below 10^{13} M_{sun}. (Abridged)

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Galaxy halo masses and satellite fractions from galaxy-galaxy lensing in the SDSS: stellar mass, luminosity, morphology, and environment dependencies does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Galaxy halo masses and satellite fractions from galaxy-galaxy lensing in the SDSS: stellar mass, luminosity, morphology, and environment dependencies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Galaxy halo masses and satellite fractions from galaxy-galaxy lensing in the SDSS: stellar mass, luminosity, morphology, and environment dependencies will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-335985

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.