Measurements of the total amount of stars locked up in galaxies as a function
of host halo mass contain key clues about the efficiency of processes that
regulate star formation. We derive the total stellar mass fraction f_star as a
function of halo mass M500c from z=0.2 to z=1 using two complementary methods.
First, we derive f_star using a statistical Halo Occupation Distribution model
jointly constrained by data from lensing, clustering, and the stellar mass
function. This method enables us to probe f_star over a much wider halo mass
range than with group or cluster catalogs. Second, we derive f_star at group
scales using a COSMOS X-ray group catalog and we show that the two methods
agree to within 30%. We quantify the systematic uncertainty on f_star using
abundance matching methods and we show that the statistical uncertainty on
f_star (~10%) is dwarfed by systematic uncertainties associated with stellar
mass measurements (~45% excluding IMF uncertainties). Assuming a Chabrier IMF,
we find 0.012<f_star<0.025 at M500c=10^13 Msun and 0.0057<f_star<0.015 at
M500c=10^14 Msun. These values are significantly lower than previously
published estimates. We investigate the cause of this difference and find that
previous work has overestimated f_star due to a combination of inaccurate
stellar mass estimators and/or because they have assumed that all galaxies in
groups are early type galaxies with a constant mass-to-light ratio. Contrary to
previous claims, our results suggest that the mean value of f_star is always
significantly lower than f_gas for halos above 10^13 Msun. Combining our
results with recently published gas mas fractions, we find a shortfall in
f_star+f_gas at R500c compared to the cosmic mean. This shortfall varies with
halo mass and becomes larger towards lower halos masses.
Description
[1109.0010] The integrated stellar content of dark matter halos
%0 Generic
%1 Leauthaud2011
%A Leauthaud, Alexie
%A George, Matthew R.
%A Behroozi, Peter S.
%A Bundy, Kevin
%A Tinker, Jeremy
%A Wechsler, Risa H.
%A Conroy, Charlie
%A Finoguenov, Alexis
%A Tanaka, Masayuki
%D 2011
%K dark halos masses matter sellar
%T The integrated stellar content of dark matter halos
%U http://arxiv.org/abs/1109.0010
%X Measurements of the total amount of stars locked up in galaxies as a function
of host halo mass contain key clues about the efficiency of processes that
regulate star formation. We derive the total stellar mass fraction f_star as a
function of halo mass M500c from z=0.2 to z=1 using two complementary methods.
First, we derive f_star using a statistical Halo Occupation Distribution model
jointly constrained by data from lensing, clustering, and the stellar mass
function. This method enables us to probe f_star over a much wider halo mass
range than with group or cluster catalogs. Second, we derive f_star at group
scales using a COSMOS X-ray group catalog and we show that the two methods
agree to within 30%. We quantify the systematic uncertainty on f_star using
abundance matching methods and we show that the statistical uncertainty on
f_star (~10%) is dwarfed by systematic uncertainties associated with stellar
mass measurements (~45% excluding IMF uncertainties). Assuming a Chabrier IMF,
we find 0.012<f_star<0.025 at M500c=10^13 Msun and 0.0057<f_star<0.015 at
M500c=10^14 Msun. These values are significantly lower than previously
published estimates. We investigate the cause of this difference and find that
previous work has overestimated f_star due to a combination of inaccurate
stellar mass estimators and/or because they have assumed that all galaxies in
groups are early type galaxies with a constant mass-to-light ratio. Contrary to
previous claims, our results suggest that the mean value of f_star is always
significantly lower than f_gas for halos above 10^13 Msun. Combining our
results with recently published gas mas fractions, we find a shortfall in
f_star+f_gas at R500c compared to the cosmic mean. This shortfall varies with
halo mass and becomes larger towards lower halos masses.
@misc{Leauthaud2011,
abstract = { Measurements of the total amount of stars locked up in galaxies as a function
of host halo mass contain key clues about the efficiency of processes that
regulate star formation. We derive the total stellar mass fraction f_star as a
function of halo mass M500c from z=0.2 to z=1 using two complementary methods.
First, we derive f_star using a statistical Halo Occupation Distribution model
jointly constrained by data from lensing, clustering, and the stellar mass
function. This method enables us to probe f_star over a much wider halo mass
range than with group or cluster catalogs. Second, we derive f_star at group
scales using a COSMOS X-ray group catalog and we show that the two methods
agree to within 30%. We quantify the systematic uncertainty on f_star using
abundance matching methods and we show that the statistical uncertainty on
f_star (~10%) is dwarfed by systematic uncertainties associated with stellar
mass measurements (~45% excluding IMF uncertainties). Assuming a Chabrier IMF,
we find 0.012<f_star<0.025 at M500c=10^13 Msun and 0.0057<f_star<0.015 at
M500c=10^14 Msun. These values are significantly lower than previously
published estimates. We investigate the cause of this difference and find that
previous work has overestimated f_star due to a combination of inaccurate
stellar mass estimators and/or because they have assumed that all galaxies in
groups are early type galaxies with a constant mass-to-light ratio. Contrary to
previous claims, our results suggest that the mean value of f_star is always
significantly lower than f_gas for halos above 10^13 Msun. Combining our
results with recently published gas mas fractions, we find a shortfall in
f_star+f_gas at R500c compared to the cosmic mean. This shortfall varies with
halo mass and becomes larger towards lower halos masses.
},
added-at = {2011-09-02T05:44:58.000+0200},
author = {Leauthaud, Alexie and George, Matthew R. and Behroozi, Peter S. and Bundy, Kevin and Tinker, Jeremy and Wechsler, Risa H. and Conroy, Charlie and Finoguenov, Alexis and Tanaka, Masayuki},
biburl = {https://www.bibsonomy.org/bibtex/27e0da24f8cfc07859fe87a25a597420d/miki},
description = {[1109.0010] The integrated stellar content of dark matter halos},
interhash = {9e8086d6407ede00dc0eb393bb4d10b6},
intrahash = {7e0da24f8cfc07859fe87a25a597420d},
keywords = {dark halos masses matter sellar},
note = {cite arxiv:1109.0010Comment: Submitted to ApJ. 16 Pages, 11 Figures. Comments Welcome},
timestamp = {2011-09-02T05:44:58.000+0200},
title = {The integrated stellar content of dark matter halos},
url = {http://arxiv.org/abs/1109.0010},
year = 2011
}