SPT-CL J2040-4451: AN SZ-SELECTED GALAXY CLUSTER AT z=1.478 WITH SIGNIFICANT ONGOING STAR FORMATION

Bayliss, MB; Ashby, MLN; Ruel, J.; Brodwin M.; Aird, KA; Bautz, MW; Benson, BA; Bleem, LE; Bocquet S.; Carlstrom, JE; Chang, CL; Cho, HM; Clocchiattii, A; Crawford, TM; Crites, AT; et. al.

Keywords: large-scale structure of universe, galaxies: evolution, galaxies: distances and redshifts, galaxies: clusters: individual (SPT-CL J2040-4451)

Abstract

SPT-CL J2040-4451-spectroscopically confirmed at z = 1.478-is the highest-redshift galaxy cluster yet discovered via the Sunyaev-Zel'dovich effect. SPT-CL J2040-4451 was a candidate galaxy cluster identified in the first 720 deg(2) of the South Pole Telescope Sunyaev-Zel'dovich (SPT-SZ) survey, and has been confirmed in follow-up imaging and spectroscopy. From multi-object spectroscopy with Magellan-I/Baade+ IMACS we measure spectroscopic redshifts for 15 cluster member galaxies, all of which have strong [O Pi]lambda lambda 3727 emission. SPT-CL J2040-4451 has an SZ-measured mass of M-500,(SZ) = 3.2 +/- 0.8 x 10(14)M(circle dot) h(-1) 70, corresponding to M-200,M- (SZ) = 5.8 +/- 1.4 x 10(14)M(circle dot) h(70-)(1.) The velocity dispersion measured entirely from blue star-forming members is sv = 1500 +/- 520 km s(-1). The prevalence of star-forming cluster members (galaxies with > 1.5M(circle dot) yr(-1)) implies that this massive, high-redshift cluster is experiencing a phase of active star formation, and supports recent results showing a marked increase in star formation occurring in galaxy clusters at z greater than or similar to 1.4. We also compute the probability of finding a cluster as rare as this in the SPT-SZ survey to be > 99%, indicating that its discovery is not in tension with the concordance Lambda CDM cosmological model.

Más información

Título según WOS: SPT-CL J2040-4451: AN SZ-SELECTED GALAXY CLUSTER AT z=1.478 WITH SIGNIFICANT ONGOING STAR FORMATION
Título según SCOPUS: SPT-CL J2040-4451: An SZ-selected galaxy cluster at z = 1.478 with significant ongoing star formation
Título de la Revista: ASTROPHYSICAL JOURNAL
Volumen: 794
Número: 1
Editorial: IOP Publishing
Fecha de publicación: 2014
Idioma: English
DOI:

10.1088/0004-637X/794/1/12

Notas: ISI, SCOPUS