A Caltech Library Service

HST Grism Confirmation of Two z ~ 2 Structures from the Clusters around Radio-loud AGN (CARLA) Survey

Noirot, Gaël and Vernet, Joël and de Breuck, Carlos and Wylezalek, Dominika and Galametz, Audrey and Stern, Daniel and Mei, Simona and Brodwin, Mark and Cooke, Elizabeth A. and Gonzalez, Anthony H. and Hatch, Nina A. and Rettura, Alessandro and Stanford, Spencer Adam (2016) HST Grism Confirmation of Two z ~ 2 Structures from the Clusters around Radio-loud AGN (CARLA) Survey. Astrophysical Journal, 830 (2). Art. No. 90. ISSN 0004-637X. doi:10.3847/0004-637X/830/2/90.

[img] PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


Using Hubble Space Telescope slitless grism data, we report the spectroscopic confirmation of two distant structures at z ~ 2 associated with powerful high-redshift radio-loud active galactic nuclei (AGNs). These rich structures, likely (forming) clusters, are among the most distant structures currently known, and were identified on the basis of Spitzer/IRAC [3.6]–[4.5] color. We spectroscopically confirm nine members in the field of MRC 2036−254, comprising eight star-forming galaxies and the targeted radio galaxy. The median redshift is z = 2.000. We spectroscopically confirm 10 members in the field of B3 0756+406, comprising 8 star-forming galaxies and 2 AGNs, including the targeted radio-loud quasar. The median redshift is z = 1.986. All confirmed members are within 500 kpc (1 arcmin) of the targeted AGNs. We derive median (mean) star-formation rates of ~ 35 M_⊙ yr^(-1) (~ 50 M_⊙ yr^(-1)) for the confirmed star-forming members of both structures based on their [O iii]λ 5007 luminosities, and estimate average galaxy stellar masses ≾ 1 x 10^(11) M_⊙ based on mid-infrared fluxes and spectral energy distribution modeling. Most of our confirmed members are located above the star-forming main sequence toward starburst galaxies, consistent with clusters at these early epochs being the sites of significant levels of star formation. The structure around MRC 2036−254 shows an overdensity of IRAC-selected candidate galaxy cluster members consistent with being quiescent galaxies, while the structure around B3 0756+406 shows field values, albeit with many lower limits to colors that could allow an overdensity of faint red quiescent galaxies. The structure around MRC 2036−254 shows a red sequence of passive galaxy candidates.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
de Breuck, Carlos0000-0002-6637-3315
Wylezalek, Dominika0000-0003-2212-6045
Galametz, Audrey0000-0002-1504-8117
Stern, Daniel0000-0003-2686-9241
Mei, Simona0000-0002-2849-559X
Brodwin, Mark0000-0002-4208-798X
Cooke, Elizabeth A.0000-0003-3843-8393
Gonzalez, Anthony H.0000-0002-0933-8601
Rettura, Alessandro0000-0002-5615-256X
Additional Information:© 2016. The American Astronomical Society. Received 2016 January 31; revised 2016 July 20; accepted 2016 July 29; published 2016 October 14. We thank our anonymous referee for comments and suggestions that improved the quality of this paper. This work is based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. This work is also based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with NASA. This work is also based in part on observations made with the 200 inch Hale Telescope, Palomar Observatory, operated by the California Institute of Technology. D.W. acknowledges support by Akbari-Mack Postdoctoral Fellowship. S.M. acknowledges financial support from the Institut Universitaire de France (IUF), of which she is senior member. E.A.C. acknowledges the support of the STFC. N.A.H. acknowledges support from STFC through an Ernest Rutherford Fellowship. Facilities: HST (WFC3, STScI), Spitzer (IRAC, JPL/Caltech), Palomar (DBSP, Caltech).
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
NASANAS 5-26555
Akbari-Mack Postdoctoral FellowshipUNSPECIFIED
Institut Universitaire de France (IUF)UNSPECIFIED
Science and Technology Facilities Council (STFC)UNSPECIFIED
Subject Keywords:galaxies: clusters: individual (CARLA J2039-2514, CARLA J0800+4029) ; galaxies: high-redshift; galaxies: individual (MRC 2036-254, B3 0756+406)
Issue or Number:2
Record Number:CaltechAUTHORS:20161014-101529864
Persistent URL:
Official Citation:Gaël Noirot et al 2016 ApJ 830 90
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:71092
Deposited By: George Porter
Deposited On:14 Oct 2016 21:34
Last Modified:11 Nov 2021 04:39

Repository Staff Only: item control page