The Chandra COSMOS Legacy Survey: Energy Spectrum of the Cosmic X-Ray Background and Constraints on Undetected Populations

被引：74

作者：

Cappelluti, Nico ^{[1
,2
,3
]}

Li, Yanxia ^{[1
,2
,3
,4
]}

Ricarte, Angelo ^{[3
]}

Agarwal, Bhaskar ^{[1
,2
,3
]}

Allevato, Viola ^{[5
]}

Ananna, Tonima Tasnim ^{[1
,2
,3
]}

Ajello, Marco ^{[6
]}

Civano, Francesca ^{[7
]}

Comastri, Andrea ^{[8
]}

Elvis, Martin ^{[7
]}

Finoguenov, Alexis ^{[5
,9
]}

Gilli, Roberto ^{[8
]}

Hasinger, Guenther ^{[4
]}

Marchesi, Stefano ^{[6
]}

Natarajan, Priyamvada ^{[1
,2
,3
]}

Pacucci, Fabio ^{[2
]}

Treister, E. ^{[10
]}

Urry, C. Megan ^{[1
,2
,3
]}

机构：

[1] Yale Ctr Astron & Astrophys, POB 208121, New Haven, CT 06504 USA

[2] Yale Univ, Dept Phys, POB 208121, New Haven, CT 06520 USA

[3] Yale Univ, Dept Astron, POB 208101, New Haven, CT 06520 USA

[4] Univ Hawaii, Inst Astron, 2680 Woodlawn Dr, Honolulu, HI 96822 USA

[5] Univ Helsinki, Dept Phys, Gustaf Hallstromin Katu 2a, FI-00014 Helsinki, Finland

[6] Clemson Univ, Dept Phys & Astron, Kinard Lab Phys, Clemson, SC 29634 USA

[7] Harvard Smithsonian Ctr Astrophys, 60 Garden St, Cambridge, MA 02138 USA

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

[9] Max Planck Inst Extraterr Phys, Postfach 1312, D-85741 Garching, Germany

[10] Pontificia Univ Catolica Chile, Fac Fis, Inst Astrofis, Casilla 306, Santiago 22, Chile

来源：

ASTROPHYSICAL JOURNAL | 2017年 / 837卷 / 01期

基金：

美国国家科学基金会;

关键词：

catalogs; infrared: diffuse background; quasars: supermassive black holes; surveys; X-rays: diffuse background; ACTIVE GALACTIC NUCLEI; POINT-SOURCE CATALOG; 1ST BLACK-HOLES; XMM-NEWTON; EVOLUTION; ABSORPTION; MODEL; IDENTIFICATION; FLUCTUATIONS; LUMINOSITY;

D O I：

10.3847/1538-4357/aa5ea4

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

Using Chandra observations in the 2.15 deg(2) COSMOS-legacy field, we present one of the most accurate measurements of the Cosmic X-ray Background (CXB) spectrum to date in the [0.3-7] keV energy band. The CXB has three distinct components: contributions from two Galactic collisional thermal plasmas at kT similar to 0.27 and 0.07 keV and an extragalactic power law with a photon spectral index Gamma = 1.45 +/- 0.02. The 1 keV normalization of the extragalactic component is 10.91 +/- 0.16 keV cm(-2) s(-1) sr(-1) keV(-1). Removing all X-ray-detected sources, the remaining unresolved CXB is best fit by a power law with normalization 4.18 +/- 0.26 keV cm(-2) s(-1) sr(-1) keV(-1) and photon spectral index Gamma = 1.57 +/- 0.10. Removing faint galaxies down to i(AB) similar to 27-28 leaves a hard spectrum with Gamma similar to 1.25 and a 1 keV normalization of similar to 1.37 keV cm(-2) s(-1) sr(-1) keV(-1). This means that similar to 91% of the observed CXB is resolved into detected X-ray sources and undetected galaxies. Unresolved sources that contribute similar to 8%-9% of the total CXB show marginal evidence of being harder and possibly more obscured than resolved sources. Another similar to 1% of the CXB can be attributed to still undetected star-forming galaxies and absorbed active galactic nuclei. According to these limits, we investigate a scenario where early black holes totally account for non-source CXB fraction and constrain some of their properties. In order to not exceed the remaining CXB and the z similar to 6 accreted mass density, such a population of black holes must grow in Compton-thick envelopes with N-H > 1.6 x 10(25) cm(-2) and form in extremely low-metallicity environments (Z(circle dot)) similar to 10(-3).

引用

页数：8

共 61 条

[1] COSMIC X-RAY BACKGROUND AND EARTH ALBEDO SPECTRA WITH SWIFT BAT [J].

Ajello, M. ;

Greiner, J. ;

Sato, G. ;

Willis, D. R. ;

Kanbach, G. ;

Strong, A. W. ;

Diehl, R. ;

Hasinger, G. ;

Gehrels, N. ;

Markwardt, C. B. ;

Tueller, J. .

ASTROPHYSICAL JOURNAL, 2008, 689 (02) :666-677

[2]

Arnaud KA, 1996, ASTR SOC P, V101, P17

[3] LIFTING THE VEIL ON OBSCURED ACCRETION: ACTIVE GALACTIC NUCLEI NUMBER COUNTS AND SURVEY STRATEGIES FOR IMAGING HARD X-RAY MISSIONS [J].

Ballantyne, D. R. ;

Draper, A. R. ;

Madsen, K. K. ;

Rigby, J. R. ;

Treister, E. .

ASTROPHYSICAL JOURNAL, 2011, 736 (01)

[4] The cosmic evolution of hard X-ray-selected active galactic nuclei [J].

Barger, AJ ;

Cowie, LL ;

Mushotzky, RF ;

Yang, Y ;

Wang, WH ;

Steffen, AT ;

Capak, P .

ASTRONOMICAL JOURNAL, 2005, 129 (02) :578-609

[5] Chandra ACIS-I particle background: an analytical model [J].

Bartalucci, I. ;

Mazzotta, P. ;

Bourdin, H. ;

Vikhlinin, A. .

ASTRONOMY & ASTROPHYSICS, 2014, 566

[6] THE X-RAY STAR FORMATION STORY AS TOLD BY LYMAN BREAK GALAXIES IN THE 4 Ms CDF-S [J].

Basu-Zych, Antara R. ;

Lehmer, Bret D. ;

Hornschemeier, Ann E. ;

Bouwens, Rychard J. ;

Fragos, Tassos ;

Oesch, Pascal A. ;

Belczynski, Krzysztof ;

Brandt, W. N. ;

Kalogera, Vassiliki ;

Luo, Bin ;

Miller, Neal ;

Mullaney, James R. ;

Tzanavaris, Panayiotis ;

Xue, Yongquan ;

Zezas, Andreas .

ASTROPHYSICAL JOURNAL, 2013, 762 (01)

[7] The first release COSMOS optical and near-IR data and catalog [J].

Capak, P. ;

Aussel, H. ;

Ajiki, M. ;

McCracken, H. J. ;

Mobasher, B. ;

Scoville, N. ;

Shopbell, P. ;

Taniguchi, Y. ;

Thompson, D. ;

Tribiano, S. ;

Sasaki, S. ;

Blain, A. W. ;

Brusa, M. ;

Carilli, C. ;

Comastri, A. ;

Carollo, C. M. ;

Cassata, P. ;

Colbert, J. ;

Ellis, R. S. ;

Elvis, M. ;

Giavalisco, M. ;

Green, W. ;

Guzzo, L. ;

Hasinger, G. ;

Ilbert, O. ;

Impey, C. ;

Jahnke, K. ;

Kartaltepe, J. ;

Kneib, J.-P. ;

Koda, J. ;

Koekemoer, A. ;

Komiyama, Y. ;

Leauthaud, A. ;

Lefevre, O. ;

Lilly, S. ;

Liu, C. ;

Massey, R. ;

Miyazaki, S. ;

Murayama, T. ;

Nagao, T. ;

Peacock, J. A. ;

Pickles, A. ;

Porciani, C. ;

Renzini, A. ;

Rhodes, J. ;

Rich, M. ;

Salvato, M. ;

Sanders, D. B. ;

Scarlata, C. ;

Schiminovich, D. .

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2007, 172 (01) :99-116

[8] CHANDRA COUNTERPARTS OF CANDELS GOODS-S SOURCES [J].

Cappelluti, N. ;

Comastri, A. ;

Fontana, A. ;

Zamorani, G. ;

Amorin, R. ;

Castellano, M. ;

Merlin, E. ;

Santini, P. ;

Elbaz, D. ;

Schreiber, C. ;

Shu, X. ;

Wang, T. ;

Dunlop, J. S. ;

Bourne, N. ;

Bruce, V. A. ;

Buitrago, F. ;

Michalowski, Michal J. ;

Derriere, S. ;

Ferguson, H. C. ;

Faber, S. M. ;

Vito, F. .

ASTROPHYSICAL JOURNAL, 2016, 823 (02)

[9] CROSS-CORRELATING COSMIC INFRARED AND X-RAY BACKGROUND FLUCTUATIONS: EVIDENCE OF SIGNIFICANT BLACK HOLE POPULATIONS AMONG THE CIB SOURCES [J].

Cappelluti, N. ;

Kashlinsky, A. ;

Arendt, R. G. ;

Comastri, A. ;

Fazio, G. G. ;

Finoguenov, A. ;

Hasinger, G. ;

Mather, J. C. ;

Miyaji, T. ;

Moseley, S. H. .

ASTROPHYSICAL JOURNAL, 2013, 769 (01)

[10] The nature of the unresolved extragalactic cosmic soft X-ray background [J].

Cappelluti, N. ;

Ranalli, P. ;

Roncarelli, M. ;

Arevalo, P. ;

Zamorani, G. ;

Comastri, A. ;

Gilli, R. ;

Rovilos, E. ;

Vignali, C. ;

Allevato, V. ;

Finoguenov, A. ;

Miyaji, T. ;

Nicastro, F. ;

Georgantopoulos, I. ;

Kashlinsky, A. .

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2012, 427 (01) :651-663

← 1 2 3 4 5 6 7 →