The XMM-Newton wide-field survey in the COSMOS field.: II.: X-ray data and the log N-log S relations

被引:118
作者
Cappelluti, N. [1 ]
Hasinger, G.
Brusa, M.
Comastri, A.
Zamorani, G.
Boehringer, H.
Brunner, H.
Civano, F.
Finoguenov, A.
Fiore, F.
Gilli, R.
Griffiths, R. E.
Mainieri, V.
Matute, I.
Miyaji, T.
Silverman, J.
机构
[1] Max Planck Inst Extraterr Phys, D-85478 Garching, Germany
[2] Osservatorio Astron Bologna, INAF, I-40127 Bologna, Italy
[3] Univ Bologna, Dipartmento Astron, I-40127 Bologna, Italy
[4] Osserv Astron Roma, INAF, I-00044 Frascati, Italy
[5] Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA
关键词
cosmology : observations; dark matter; galaxies : evolution; galaxies : formation; large-scale structure of universe; surveys;
D O I
10.1086/516586
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present data analysis and X- ray source counts for the first season of XMM- Newton observations in the COSMOS field. The survey covers similar to 2 deg(2) within the region of sky bounded by 09(h)57(m)30(s) < R. A. < 10(h)03(m)30(s), 01 degrees 27'30 '' < decl. < 02 degrees 57'30 '' with a total net integration time of 504 ks. A maximum likelihood source detection was performed in the 0.5-2, 2-4.5, and 4.5-10 keVenergy bands, and 1390 pointlike sources were detected in at least one band. Detailed Monte Carlo simulations were performed to fully test the source- detection method and to derive the sky coverage to be used in the computation of the log N-log S relations. These relations were then derived in the 0.5-2, 2-10, and 5-10 keVenergy bands, down to flux limits of 7.2x10(-16) ergs cm(-2) s(-1), 4.0x10(-15) ergs cm(-2) s(-1), and 9.7x10(-15) ergs cm(-2) s(-1), respectively. Thanks to the large number of sources detected in the COSMOS survey, the log N-log S curves are tightly constrained over a range of fluxes which were poorly covered by previous surveys, especially in the 2-10 and 5-10 keV bands. The 0.5-2 and 2-10 keV differential log N -log S relations were fitted with a broken power-law model which revealed a Euclidean slope at the bright end and a flatter slope (alpha similar to 1.5) at faint fluxes. In the 5-10 keVenergy band a single power law provides an acceptable fit to the observed source counts with a slope alpha similar to 2.4. A comparison with the results of previous surveys shows good agreement in all the energy bands under investigation in the overlapping flux range. We also notice a remarkable agreement between our log N -log S relations and the most recent model of the X- ray background.
引用
收藏
页码:341 / 352
页数:12
相关论文
共 57 条
[1]   The HELLAS2XMM survey.: I.: The X-ray data and the log N-log S relation [J].
Baldi, A ;
Molendi, S ;
Comastri, A ;
Fiore, F ;
Matt, G ;
Vignali, C .
ASTROPHYSICAL JOURNAL, 2002, 564 (01) :190-195
[2]   The fall of active galactic nuclei and the rise of star-forming galaxies: A close look at the Chandra Deep Field X-ray number counts [J].
Bauer, FE ;
Alexander, DM ;
Brandt, WN ;
Schneider, DP ;
Treister, E ;
Hornschemeier, AE ;
Garmire, GP .
ASTRONOMICAL JOURNAL, 2004, 128 (05) :2048-2065
[3]   Deep extragalactic X-ray surveys [J].
Brandt, WN ;
Hasinger, G .
ANNUAL REVIEW OF ASTRONOMY AND ASTROPHYSICS, 2005, 43 :827-859
[4]   The XMM-Newton wide-field survey in the COSMOS field.: III.: Optical identification and multiwavelength properties of a large sample of X-ray-selected sources [J].
Brusa, M. ;
Zamorani, G. ;
Comastri, A. ;
Hasinger, G. ;
Cappelluti, N. ;
Civano, F. ;
Finoguenov, A. ;
Mainieri, V. ;
Salvato, M. ;
Vignali, C. ;
Elvis, M. ;
Fiore, F. ;
Gilli, R. ;
Impey, C. D. ;
Lilly, S. J. ;
Mignoli, M. ;
Silverman, J. ;
Trump, J. ;
Urry, C. M. ;
Bender, R. ;
Capak, P. ;
Huchra, J. P. ;
Kneib, J. P. ;
Koekemoer, A. ;
Leauthaud, A. ;
Lehmann, I. ;
Massey, R. ;
Matute, I. ;
McCarthy, P. J. ;
McCracken, H. J. ;
Rhodes, J. ;
Scoville, N. Z. ;
Taniguchi, Y. ;
Thompson, D. .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2007, 172 (01) :353-367
[5]   X-ray source overdensities in Chandra distant cluster fields: A new probe to map the cosmic tapestry? [J].
Cappelluti, N ;
Cappi, M ;
Dadina, M ;
Malaguti, G ;
Branchesi, M ;
D'Elia, V ;
Palumbo, GGC .
ASTRONOMY & ASTROPHYSICS, 2005, 430 (01) :39-45
[6]  
CAPPELLUTI N, 2006, IN PRESS A A
[7]   Chandra study of an overdensity of X-ray sources around two distant (z ∼ 0.5) clusters [J].
Cappi, M ;
Mazzotta, P ;
Elvis, M ;
Burke, DJ ;
Comastri, A ;
Fiore, F ;
Forman, W ;
Fruscione, A ;
Green, P ;
Harris, D ;
Hooper, EJ ;
Jones, C ;
Kaastra, JS ;
Kellogg, E ;
Murray, S ;
McNamara, B ;
Nicastro, F ;
Ponman, TJ ;
Schlegel, EM ;
Siemiginowska, A ;
Tananbaum, H ;
Vikhlinin, A ;
Virani, S ;
Wilkes, B .
ASTROPHYSICAL JOURNAL, 2001, 548 (02) :624-638
[8]  
CAVALIERE A, 1976, ASTRON ASTROPHYS, V49, P137
[9]  
COMASTRI A, 1995, ASTRON ASTROPHYS, V296, P1
[10]   The 2-8 keV cosmic X-ray background spectrum as observed with XMM-Newton [J].
De Luca, A ;
Molendi, S .
ASTRONOMY & ASTROPHYSICS, 2004, 419 (03) :837-848