A Caltech Library Service

The close environment of 24 μm galaxies at 0.6 < z < 1.0 in the cosmos field

Caputi, K. I. and Kovač, K. and Bolzonella, M. and Lilly, S. J. and Zamorani, G. and Aussel, H. and Sanders, D. and Bardelli, S. and Bongiorno, A. and Contini, T. and Coppa, G. and Cucciati, O. and de la Torre, S. and de Ravel, L. and Franzetti, P. and Frayer, D. and Garilli, B. and Iovino, A. and Kampczyk, P. and Kneib, J.-P. and Knobel, C. and Lamareille, F. and Le Borgne, J. -F. and Le Brun, V. and Le Fèvre, O. and Le Floc'h, E. and Leauthaud, A. and Maier, C. and Mainieri, V. and Mignoli, M. and Pellò, R. and Peng, Y. and Pérez-Montero, E. and Ricciardelli, E. and Salvato, M. and Scodeggio, M. and Scoville, N. and Silverman, J. and Surace, J. and Tanaka, M. and Tasca, L. and Tresse, L. and Vergani, D. and Zucca, E. and Abbas, U. and Bottini, D. and Capak, P. and Cappi, A. and Carollo, M. and Cassata, P. and Cimatti, A. and Fumana, M. and Ilbert, O. and Kartaltepe, J. and Maccagni, D. and Marinoni, C. and McCracken, H. and Memeo, P. and Meneux, B. and Oesch, P. and Porciani, C. and Pozzetti, L. and Renzini, A. and Scaramella, R. and Scarlata, C. (2009) The close environment of 24 μm galaxies at 0.6 < z < 1.0 in the cosmos field. Astrophysical Journal, 691 (1). pp. 91-97. ISSN 0004-637X. doi:10.1088/0004-637X/691/1/91.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We investigate the close environment of 203 Spitzer 24 μm -selected sources at 0.6 < z < 1.0 using zCOSMOS-bright redshifts and spectra of I < 22.5 AB mag galaxies, over 1.5 deg^2 of the COSMOS field. We quantify the degree of passivity of the luminous and ultra-luminous IR galaxy (LIRG and ULIRG, respectively) environments by analyzing the fraction of close neighbors with Dn(4000)>1.4. We find that LIRGs at 0.6 < z < 0.8 live in more passive environments than those of other optical galaxies that have the same stellar mass distribution. Instead, ULIRGs inhabit more active regions (e.g., LIRGs and ULIRGs at 0.6 < z < 0.8 have, respectively, (42.0 ± 4.9)% and (24.5 ± 5.9)% of neighbors with Dn(4000)>1.4 within 1 Mpc and ±500 km s^–1). The contrast between the activities of the close environments of LIRGs and ULIRGs appears especially enhanced in the COSMOS field density peak at z ~ 0.67, because LIRGs on this peak have a larger fraction of passive neighbors, while ULIRGs have as active close environments as those outside the large-scale structure. The differential environmental activity is related to the differences in the distributions of stellar mass ratios between LIRGs/ULIRGs and their close neighbors, as well as in the general local density fields. At 0.8 < z < 1.0, instead, we find no differences in the environment densities of ULIRGs and other similarly massive galaxies, in spite of the differential activities. We discuss a possible scenario to explain these findings.

Item Type:Article
Related URLs:
URLURL TypeDescription
Caputi, K. I.0000-0001-8183-1460
Lilly, S. J.0000-0002-6423-3597
Aussel, H.0000-0002-1371-5705
Sanders, D.0000-0002-1233-9998
Cucciati, O.0000-0002-9336-7551
de la Torre, S.0000-0002-0839-2884
Frayer, D.0000-0003-1924-1122
Kneib, J.-P.0000-0002-4616-4989
Le Fèvre, O.0000-0001-5891-2596
Leauthaud, A.0000-0002-3677-3617
Salvato, M.0000-0001-7116-9303
Scoville, N.0000-0002-0438-3323
Silverman, J.0000-0002-0000-6977
Surace, J.0000-0001-7291-0087
Tanaka, M.0000-0002-5011-5178
Capak, P.0000-0003-3578-6843
Carollo, M.0000-0003-1624-7609
Ilbert, O.0000-0002-7303-4397
Kartaltepe, J.0000-0001-9187-3605
McCracken, H.0000-0002-9489-7765
Oesch, P.0000-0001-5851-6649
Renzini, A.0000-0002-7093-7355
Scarlata, C.0000-0002-9136-8876
Additional Information:© 2009. Received 2008 June 6; accepted 2008 September 19; published 2009 January 7. This paper is based on observations made with the VIMOS spectrograph on the VLT telescope, undertaken at the European Southern Observatory (ESO) under Large Program 175.A-0839, and also based on observations made with the Spitzer Observatory, which is operated under NASA contract 1407.
Group:COSMOS, Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
Subject Keywords:galaxies: evolution – infrared: galaxies
Issue or Number:1
Record Number:CaltechAUTHORS:20090417-103246449
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:14007
Deposited By: Marie Noren
Deposited On:21 Apr 2009 22:35
Last Modified:08 Nov 2021 22:42

Repository Staff Only: item control page