Change search
ReferencesLink to record
Permanent link

Direct link
Show others and affiliations
2010 (English)In: Astrophysical Journal, ISSN 0004-637X, E-ISSN 1538-4357, Vol. 718, no 1, 133-147 p.Article in journal (Refereed) Published
Abstract [en]

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 at z = 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(-0.9)(+0.6) keV and luminosity LX = (2.92(-0.35)(+0.24)) x 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 sigma(v)-T relation, but the cluster remains less luminous than would be expected from self-similar evolution of the local L-X-T relation. Two of the newly discovered X-ray AGNs are cluster members, while a third object, which is also a prominent 24 mu m 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 > 5 sigma 24 mu m sources associated with cluster members (four spectroscopically confirmed and four selected using photometric redshifts) and one additional 24 mu m 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 mu m sources are powered by star formation, their IR luminosities imply star formation rates similar to 100 M-circle dot yr(-1). We find that three of these sources are located at projected distances of <250 kpc from the cluster center, suggesting that a large amount of star formation may be taking place in the cluster core, in contrast to clusters at low redshift.

Place, publisher, year, edition, pages
2010. Vol. 718, no 1, 133-147 p.
Keyword [en]
galaxies: active, galaxies: clusters: individual (XMMXCS J2215.9-1738), galaxies: star formation, X-rays: galaxies: clusters
National Category
Natural Sciences
URN: urn:nbn:se:su:diva-49695DOI: 10.1088/0004-637X/718/1/133ISI: 000280340800014OAI: diva2:379336
authorCount :14Available from: 2010-12-17 Created: 2010-12-17 Last updated: 2011-05-09Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full text

Search in DiVA

By author/editor
Sahlén, Martin
By organisation
Department of PhysicsThe Oskar Klein Centre for Cosmo Particle Physics (OKC)
In the same journal
Astrophysical Journal
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 103 hits
ReferencesLink to record
Permanent link

Direct link