Dust-obscured star formation in the outskirts of XMMU J2235.3-2557, a massive galaxy cluster at z=1.4

作者:Santos J S*; Altieri B; Popesso P; Strazzullo V; Valtchanov I; Berta S; Boehringer H; Conversi L; Demarco R; Edge A C; Lidman C; Lutz D; Metcalfe L; Mullis C R; Pintos Castro I; Sanchez Portal M; Rawle T D; Rosati P; Swinbank A M; Tanaka M
来源:Monthly Notices of the Royal Astronomical Society, 2013, 433(2): 1287-1299.
DOI:10.1093/mnras/stt811

摘要

Star formation (SF) in the galaxy populations of local massive clusters is reduced with respect to field galaxies, and tends to be suppressed in the core region. Indications of a reversal of the SF-density relation have been observed in a few z %26gt; 1.4 clusters. Using deep imaging from 100-500 mu m from Photodetector Array Camera and Spectrometer (PACS) and Spectral and Photometric Imaging REceiver (SPIRE) onboard Herschel, we investigate infrared properties of spectroscopic and photo-z cluster members, and of H alpha emitters in XMMU J2235.3-2557, one of the most massive, distant, X-ray selected clusters known. Our analysis is based mostly on fitting of the galaxies spectral energy distribution (SED) in the rest-frame 8-1000 mu m. We measure total IR luminosity, deriving star formation rates (SFRs) ranging from 89 to 463 M-circle dot yr(-1) for 13 galaxies individually detected by Herschel, all located beyond the core region (r %26gt; 250 kpc). We perform a stacking analysis of nine star-forming members not detected by PACS, yielding a detection with SFR = 48 +/- 16 M-circle dot yr(-1). Using a colour criterion based on a star-forming galaxy SED at the cluster redshift, we select 41 PACS sources as candidate star-forming cluster members. We characterize a population of highly obscured SF galaxies in the outskirts of XMMU J2235.3-2557. We do not find evidence for a reversal of the SF-density relation in this massive, distant cluster.

  • 出版日期2013-8
  • 单位中国地震局