The nature of the unresolved extragalactic cosmic soft X-ray background

被引：51

作者：

Cappelluti, N. ^{[1
,2
]}

Ranalli, P. ^{[1
,3
,4
]}

Roncarelli, M. ^{[4
]}

Arevalo, P. ^{[5
]}

Zamorani, G. ^{[1
]}

Comastri, A. ^{[1
]}

Gilli, R. ^{[1
]}

Rovilos, E. ^{[1
]}

Vignali, C. ^{[1
,4
]}

Allevato, V. ^{[6
]}

Finoguenov, A. ^{[2
,7
]}

Miyaji, T. ^{[8
]}

Nicastro, F. ^{[9
]}

Georgantopoulos, I. ^{[1
,3
]}

Kashlinsky, A. ^{[10
,11
]}

机构：

[1] INAF, Osservatorio Astron Bologna, I-40127 Bologna, Italy

[2] Univ Maryland Baltimore Cty, Baltimore, MD 21250 USA

[3] Natl Observ Athens, Inst Astron & Astrophys, Athens 15236, Greece

[4] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy

[5] Univ Andres Bello, Dept Ciencias Fis, Santiago, Chile

[6] Max Planck Inst Plasmaphys & Excellence Cluster U, D-85748 Garching, Germany

[7] Max Planck Inst Extraterr Phys, D-85748 Garching, Germany

[8] Univ Nacl Autonoma Mexico, Inst Astron, Ensenada, Baja California, Mexico

[9] INAF, Osservatorio Astron Roma, I-00040 Monte Porzio Catone, Italy

[10] SSAI, Lanham, MD 20706 USA

[11] NASA, Goddard Space Flight Ctr, Observat Cosmol Lab, Greenbelt, MD 20771 USA

来源：

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | 2012年 / 427卷 / 01期

关键词：

galaxies: active; dark matter; diffuse radiation; large-scale structure of Universe; X-rays: galaxies; ACTIVE GALACTIC NUCLEI; WIDE-FIELD SURVEY; HOT INTERGALACTIC MEDIUM; STAR-FORMING GALAXIES; LYMAN-BREAK GALAXIES; XMM-NEWTON; MISSING BARYONS; POWER SPECTRUM; DENSITY-FLUCTUATIONS; CLUSTER CONTRIBUTION;

D O I：

10.1111/j.1365-2966.2012.21867.x

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

In this paper we investigate the power spectrum of the unresolved 0.5-2 keV cosmic X-ray background (CXB) with deep Chandra 4-Msec (Ms) observations in the Chandra Deep Field South (CDFS). We measured a signal that, on scales >30 arcsec, is significantly higher than the shot noise and is increasing with angular scale. We interpreted this signal as the joint contribution of clustered undetected sources like active galactic nuclei (AGN), galaxies and the intergalactic medium (IGM). The power of unresolved cosmic source fluctuations accounts for similar to 12 per cent of the 0.5-2 keV extragalactic CXB. Overall, our modelling predicts that similar to 20 per cent of the unresolved CXB flux is produced by low-luminosity AGN, similar to 25 per cent by galaxies and similar to 55 per cent by the IGM. We do not find any direct evidence of the so-called 'warm hot intergalactic medium' (i.e. matter with 10(5) < T < 10(7) K and density contrast delta < 1000), but we estimated that it could produce about 1/7 of the unresolved CXB. We placed an upper limit on the space density of postulated X-ray-emitting early black holes at z > 7.5 and compared it with supermassive black hole evolution models.

引用

页码：651 / 663

页数：13

共 74 条

[1] The spatial clustering of star-forming galaxies at redshifts 1.4 ≲ z ≲ 3.5 [J].