SciELO - Scientific Electronic Library Online

 
vol.47 número2Upper Main Sequence Stars with Anomalous Abundances: The HGMN Stars HR 3273, HR 8118, HR 8567 and HR 8937Spectral Morphology and Rotation in The Open Cluster NGC 6025 índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Revista mexicana de astronomía y astrofísica

versão impressa ISSN 0185-1101

Resumo

RODRIGUEZ-PUEBLA, A.; AVILA-REESE, V.; FIRMANI, C.  e  COLIN, P.. On The Stellar And Baryonic Mass Fractions Of Central Blue And Red Galaxies. Rev. mex. astron. astrofis [online]. 2011, vol.47, n.2, pp. 235-253. ISSN 0185-1101.

Using the abundance matching technique, we infer the local stellar and baryonic mass-halo mass ( Ms- Mh and Mb - Mh) 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-Ms relations. For halos associated to central BGs, the distinct ACDM 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 5 mass function to the total one is used. At Mh > 1011.5 ΜΘ, the Ms of RGs tend to be higher than those of BGs for a given Mh, the difference not being larger than 1.7. At Mh < 1011.5 ΜΘ, this trend is inverted. For BGs (RGs): (a) the maximum value of fs = Ms / Mh is 0.021+0.016 -0.009(0.034 +0.026 -0.015)and it is attained at log(MhΘ) = 12.0 (= 11.9); (b) fs ∞ Mh ( fs ∞ Mh3) at the low-mass end while at the high-mass end, fs ∞ Mh-0.4 (fs ∞ Mh-06). The baryon mass fractions, fb = Mb / Mh, of BGs and RGs reach maximum values of fb = 0.028 +0.018 -0.011 y fb = 0.034 +0.025 -0.014., respectively. At Mh < 1011.3 ΜΘ, the dependence of fb on Mh is much steeper for RGs than for BGs. We discuss the differences found in the fs - Mh and fb - Mh relations between BGs and RGs in the light of semi-empirical galaxy evolution inferences.

Palavras-chave : dark matter; galaxies [luminosity function]; galaxies [mass function].

        · resumo em Espanhol     · texto em Inglês     · pdf em Inglês