Galaxy Clusters at z ≥ 1: Gas Constraints from the Sunyaev–Zel'dovich Array

• Published in: Astrophysical journal. Letters 2010-11, Vol.723 (1), p.L78-L83
• Main Authors: Culverhouse, T. L, Bonamente, M, Bulbul, E, Carlstrom, J. E, Gralla, M. B, Greer, C, Hasler, N, Hawkins, D, Hennessy, R, Jetha, N. N, Joy, M, Lamb, J. W, Leitch, E. M, Marrone, D. P, Miller, A, Mroczkowski, T, Muchovej, S, Pryke, C, Sharp, M, Woody, D, Andreon, S, Maughan, B, Stanford, S. A
• Format: Article
• Language: English
• Subjects: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; BACKGROUND RADIATION; COSMOLOGY; ELECTROMAGNETIC RADIATION; GALAXY CLUSTERS; IONIZING RADIATIONS; MASS; RADIATIONS; RED SHIFT; X RADIATION
• ISSN: 2041-8205; 2041-8213
• DOI: 10.1088/2041-8205/723/1/L78

We present gas constraints from Sunyaev-Zel'dovich (SZ) effect measurements in a sample of 11 X-ray and infrared (IR) selected galaxy clusters at z>=1, using data from the Sunyaev-Zel'dovich Array (SZA). The cylindrically integrated Compton-y parameter, Y, is calculated by fitting the data to a two-parameter gas pressure profile. Where possible, we also determine the temperature of the hot intracluster plasma from Chandra and XMM-Newton data and constrain the gas mass within the same aperture (r 2500) as Y. The SZ effect is detected in the clusters for which the X-ray data indicate gas masses above ~1013 M , including XMMU J2235 -- 2557 at redshift z = 1.39, which to date is one of the most distant clusters detected using the SZ effect. None of the IR-selected targets are detected by the SZA measurements, indicating low gas masses for these objects. For these and the four other undetected clusters, we quote upper limits on Y and M gas,SZ, with the latter derived from scaling relations calibrated with lower redshift clusters. We compare the constraints on Y and X-ray-derived gas mass M gas,X-ray to self-similar scaling relations between these observables determined from observations of lower redshift clusters, finding consistency given the measurement error.