Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - The XMM cluster survey
T2 - Active galactic nuclei and starburst galaxies in XMMXCS J2215.9-1738 at z = 1.46
AU - Hilton, Matt
AU - Lloyd-Davies, Ed
AU - Stanford, S. Adam
AU - Stott, John P.
AU - Collins, Chris A.
AU - Romer, A. Kathy
AU - Hosmer, Mark
AU - Hoyle, Ben
AU - Kay, Scott T.
AU - Liddle, Andrew R.
AU - Mehrtens, Nicola
AU - Miller, Christopher J.
AU - Sahlén, Martin
AU - Viana, Pedro T P
PY - 2010/6/28
Y1 - 2010/6/28
N2 - We use Chandra X-ray and Spitzer infrared (IR) observations to explore the active galactic nucleus (AGN) and starburst populations of XMMXCS J2215.9-1738 atz = 1.46, one of the most distant spectroscopically confirmed galaxy clusters known. The high-resolution X-ray imaging reveals that the cluster emission is contaminated by point sources that were not resolved in XMM-Newton observations of the system, and have the effect of hardening the spectrum, leading to the previously reported temperature for this system being overestimated. From a joint spectroscopic analysis of the Chandra and XMM-Newton data, the cluster is found to have temperature T = 4.1+0.6-0.9 keV and luminosity LX = (2.92+0.24-0.35) × 1044 erg s-1, extrapolated to a radius of 2 Mpc. As a result of this revised analysis, the cluster is found to lie on the σv-T relation, but the cluster remains less luminous than would be expected from self-similar evolution of the local LX-T relation. Two of the newly discovered X-ray AGNs are cluster members, while a third object, which is also a prominent 24 μm source, is found to have properties consistent with it being a high-redshift, highly obscured object in the background. We find a total of eight >5σ 24 μm sources associated with cluster members (four spectroscopically confirmed and four selected using photometric redshifts) and one additional 24 μm source with two possible optical/near-IR counterparts that may be associated with the cluster. Examining the Infrared Array Camera colors of these sources, we find that one object is likely to be an AGN. Assuming that the other 24 μm sources are powered by star formation, their IR luminosities imply star formation rates ∼100M⊙ yr-1. We find that three of these sources are located at projected distances of
AB - We use Chandra X-ray and Spitzer infrared (IR) observations to explore the active galactic nucleus (AGN) and starburst populations of XMMXCS J2215.9-1738 atz = 1.46, one of the most distant spectroscopically confirmed galaxy clusters known. The high-resolution X-ray imaging reveals that the cluster emission is contaminated by point sources that were not resolved in XMM-Newton observations of the system, and have the effect of hardening the spectrum, leading to the previously reported temperature for this system being overestimated. From a joint spectroscopic analysis of the Chandra and XMM-Newton data, the cluster is found to have temperature T = 4.1+0.6-0.9 keV and luminosity LX = (2.92+0.24-0.35) × 1044 erg s-1, extrapolated to a radius of 2 Mpc. As a result of this revised analysis, the cluster is found to lie on the σv-T relation, but the cluster remains less luminous than would be expected from self-similar evolution of the local LX-T relation. Two of the newly discovered X-ray AGNs are cluster members, while a third object, which is also a prominent 24 μm source, is found to have properties consistent with it being a high-redshift, highly obscured object in the background. We find a total of eight >5σ 24 μm sources associated with cluster members (four spectroscopically confirmed and four selected using photometric redshifts) and one additional 24 μm source with two possible optical/near-IR counterparts that may be associated with the cluster. Examining the Infrared Array Camera colors of these sources, we find that one object is likely to be an AGN. Assuming that the other 24 μm sources are powered by star formation, their IR luminosities imply star formation rates ∼100M⊙ yr-1. We find that three of these sources are located at projected distances of
KW - Galaxies: active
KW - Galaxies: clusters: individual (XMMXCS J2215.9-1738)
KW - Galaxies: star formation
KW - X-rays: galaxies: clusters
U2 - 10.1088/0004-637X/718/1/133
DO - 10.1088/0004-637X/718/1/133
M3 - Journal article
AN - SCOPUS:78649306047
VL - 718
SP - 133
EP - 147
JO - The Astrophysical Journal
JF - The Astrophysical Journal
SN - 0004-637X
IS - 1
ER -