Stellar mass to halo mass relation from galaxy clustering in VUDS: a high star formation efficiency at z similar or equal to 3

A. Durkalec (1) , O. Le Fevre (1) , S. de La Torre (1) , A. Pollo (1) , P. Cassata (1) , B. Garilli , V. Le Brun (1) , B. C. Lemaux (1) , D. Maccagni , L. Pentericci (2) , L. A. M. Tasca (1) , R. Thomas (1) , E. Vanzella (3) , G. Zamorani (3) , E. Zucca (4) , R. Amorín (2) , S. Bardelli (5) , L. P. Cassara , M. Castellano (2) , Alessandro Cimatti (6) , O. Cucciati (5) , A. Fontana (2) , M. Giavalisco (7) , A. Grazian (2) , N. P. Hathi (1) , O. Ilbert (1) , S. Paltani (8) , B. Ribeiro (1) , D. Schaerer (9) , M. Scodeggio (10) , V. Sommariva (2) , M. Talia (6, 5) , L. Tresse (1) , D. Vereani , P. Capak (11) , S. Charlot (12) , T. Contini (9) , J. G. Cuby (1) , J. Dunlop (13) , S. Fotopoulou (14) , A. Koekemoer (15) , C. Lopez-Sanjuan (1) , Y. Mellier (12) , J. Pforr (1) , M. Salvato (16, 17) , N. Scoville (18) , Y. Taniguchi , P. W. Wang (1)

1 LAM - Laboratoire d'Astrophysique de Marseille
2 OAR - INAF - Osservatorio Astronomico di Roma
3 INAF - Istituto Nazionale di Astrofisica
4 Oncology Institute of Southern Switzerland
5 OABO - INAF - Osservatorio Astronomico di Bologna
6 UNIBO - Alma Mater Studiorum Università di Bologna = University of Bologna
7 Department of Astronomy [Amherst]
8 ISDC Data Centre for Astrophysics
9 IRAP - Institut de recherche en astrophysique et planétologie
10 INAF- Milano
11 MPIA - Max-Planck-Institut für Astronomie
12 IAP - Institut d'Astrophysique de Paris
13 SUPA, Institute for Astronomy
14 Aristotle University of Thessaloniki
15 STSci - Space Telescope Science Institute
16 MPE - Max-Planck-Institut für Extraterrestrische Physik
17 Excellence Cluster Universe
18 CALTECH - California Institute of Technology

The relation between the galaxy stellar mass M-star and the dark matter halo mass M-h gives important information on the efficiency in forming stars and assembling stellar mass in galaxies. We present measurements of the ratio of stellar mass to halo mass (SMHR) at redshifts 2 \textless z \textless 5, obtained from the VIMOS Ultra Deep Survey. We use halo occupation distribution (HOD) modelling of clustering measurements on similar to 3000 galaxies with spectroscopic redshifts to derive the dark matter halo mass M-h, and spectral energy density fitting over a large set of multi-wavelength data to derive the stellar mass M-star and compute the SMHR = M-star/M-h. We find that the SMHR ranges from 1% to 2.5% for galaxies with M-star = 1.3 x 10(9) M-star to M-star = 7.4 x 10(9) M-circle dot in DM halos with M-h = 1.3 x 10(11) M-circle dot to M-h = 3 x 10(11) M-circle dot. We derive the integrated star formation efficiency (ISFE) of these galaxies and find that the star formation efficiency is a moderate 6-9% for lower mass galaxies, while it is relatively high at 16% for galaxies with the median stellar mass of the sample similar to 7 x 10(9) M-circle dot. The lower ISFE at lower masses may indicate that some efficient means of suppressing star formation is at work (like SNe feedback), while the high ISFE for the average galaxy at z similar to 3 indicates that these galaxies efficiently build up their stellar mass at a key epoch in the mass assembly process. Based on our results, we propose a possible scenario in which the average massive galaxy at z similar to 3 begins to experience truncation of its star formation within a few million years.

Mots clés: Large-scale structure of Universe; Early Universe; Galaxies: evolution; Methods: statistical

Domaines: Astrophysique [astro-ph]

A. Durkalec, O. Le Fevre, S. de La Torre, A. Pollo, P. Cassata, et al.. Stellar mass to halo mass relation from galaxy clustering in VUDS: a high star formation efficiency at z similar or equal to 3. Astronomy and Astrophysics - A&A, 2015, 576, ⟨10.1051/0004-6361/201425532⟩. ⟨hal-01439772⟩