Abstract
Using the abundance matching technique, we infer the local stellar and baryonic mass-halo mass (M_s-M_h and M_b-M_h) relations separately for central blue and red galaxies (BGs and RGs). The observational inputs are the SDSS central BG and RG stellar mass functions and the measured gas mass-M_s relations. For halos associated to central BGs, the distinct ΛCDM halo mass function is used and set up to exclude: (i) the observed group/cluster mass function and (ii) halos with a central major merger at resdshifts z ≤ 0.8. For central RGs, the complement of this mass function to the total one is used. At M_h > 1011.5 M_⊙, the M_s of RGs tend to be higher than those of BGs for a given M_h, the difference not being larger than 1.7. At M_h < 1011.5 M_⊙, this trend is inverted. For BGs (RGs): (a) the maximum value of f^s = M_s/M_h is 0.021+0.016-0.009 (0.034+0.026-0.015) and it is attained at log(M_h/M_⊙)=12.0 (= 11.9); (b) f^s ∝ M_h (f^s ∝ M_h^3) at the low-mass end while at the high-mass end, f^s ∝ M_h-0.4 (f^s ∝ M_h-0.6). The baryon mass fractions, f_b=M_b/M_h, of BGs and RGs reach maximum values of f_b=0.028+0.018-0.011 and f_b=0.034+0.025-0.014, respectively. At M_h < 1011.3 M_⊙, the dependence of f_b on M_h is much steeper for RGs than for BGs. We discuss the differences found in the f_s-M_h and f_b-M_h relations between BGs and RGs in the light of semi-empirical galaxy evolution inferences.
