The nonlinear biasing of the 10k zCOSMOS galaxies up to z~1

K. Kovac (1) , C. Porciani , S. J. Lilly (2) , Christian Marinoni (3) , L. Guzzo , O. Cucciati (4) , G. Zamorani , A. Iovino (1) , P. Oesch (1) , M. Bolzonella , Y. Peng (5) , B. Meneux , E. Zucca , S. Bardelli , C. M. Carollo (6) , T. Contini (7) , J. -P. Kneib (8) , O. Le Fevre (9) , V. Mainieri (10) , A. Renzini , M. Scodeggio , A. Bongiorno (11) , K. Caputi (1) , G. Coppa , S. de La Torre , L. de Ravel (1) , A. Finoguenov (12) , P. Franzetti , B. Garilli , P. Kampczyk (1) , C. Knobel (1) , F. Lamareille (13) , J. -F. Le Borgne , V. Le Brun (14) , C. Maier (15) , M. Mignoli , R. Pello (13) , E. Perez Montero (16) , L. Pozzetti , E. Ricciardelli (1) , J. D. Silverman (1) , M. Tanaka , L. A. M. Tasca , L. Tresse (9) , D. Vergani (17) , U. Abbas (18) , D. Bottini (1) , A. Cappi (19) , P. Cassata , Alessandro Cimatti , M. Fumana (1) , A. M. Koekemoer , A. Leauthaud (20) , D. Maccagni (1) , H. J. Mccracken (21) , P. Memeo (1) , R. Scaramella , N. Z. Scoville (20)

1 AUTRES
2 ETH Zürich - Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich]
3 CPT - Centre de Physique Théorique - UMR 6207
4 Dipartimento di Fisica
5 HNU - Hunan Normal University
6 University of Chicago
7 LATT - Laboratoire Astrophysique de Toulouse-Tarbes
8 EPFL - Ecole Polytechnique Fédérale de Lausanne
9 LAM - Laboratoire d'Astrophysique de Marseille
10 ESO - European Southern Observatory
11 GATECH - College of Computing
12 MPE - Max-Planck-Institut für Extraterrestrische Physik
13 IRAP - Institut de recherche en astrophysique et planétologie
14 ISCOD-ENSMSE - Département Informatique pour les Systèmes Coopératifs Ouverts et Décentralisés
15 LLB - UMR 12 - Laboratoire Léon Brillouin
16 Departamento de Informatica [Valparaíso, Chile]
17 OAA - INAF - Osservatorio Astrofisico di Arcetri
18 OATo - INAF - Osservatorio Astrofisico di Torino
19 LAGRANGE - Joseph Louis LAGRANGE
20 CALTECH - California Institute of Technology
21 IAP - Institut d'Astrophysique de Paris

We use the overdensity field reconstructed in the volume of the COSMOS area to study the nonlinear biasing of the zCOSMOS galaxies. The galaxy overdensity field is reconstructed using the current sample of ~8500 accurate zCOSMOS redshifts at I(AB)<22.5 out to z~1 on scales R from 8 to 12 Mpc/h. By comparing the probability distribution function (PDF) of galaxy density contrast delta_g to the lognormal approximation of the PDF of the mass density contrast delta, we obtain the mean biasing function b(delta,z,R) between the galaxy and matter overdensity field and its second moments b(hat) and b(tilde) up to z~1. Over the redshift interval 0.4 = b(delta,z,R) delta is of the following characteristic shape. The function vanishes in the most underdense regions and then sharply rises in a nonlinear way towards the mean densities. is almost a linear tracer of the matter in the overdense regions, up to the most overdense regions in which it is nonlinear again and the local effective slope of vs. delta is smaller than unity. The function is evolving only slightly over the redshift interval 0.4

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

K. Kovac, C. Porciani, S. J. Lilly, Christian Marinoni, L. Guzzo, et al.. The nonlinear biasing of the 10k zCOSMOS galaxies up to z~1. The Astrophysical Journal, 2011, 731 (2), pp.102. ⟨10.1088/0004-637X/731/2/102⟩. ⟨hal-01113771⟩