INTEGRAL/IBIS all-sky survey in hard X-rays
INTEGRAL/IBIS all-sky survey in hard X-rays
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DOI：
10.1051/0004-6361:20077191
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发表时间：
2007-01
影响因子：
6.5
通讯作者：
R. Krivonos;M. Revnivtsev;A. Lutovinov;S. Sazonov;E. Churazov;R. M. Iki;Moscow;R. Mpa;
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文献类型：
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作者：
R. Krivonos;M. Revnivtsev;A. Lutovinov;S. Sazonov;E. Churazov;R. M. Iki;Moscow;R. Mpa;
我们展示了一项全天空硬x射线调查的结果，该调查基于INTEGRAL天文台上的IBIS望远镜近四年的观测。调查的死时校正曝光为~ 33 ms，大约12%和80%的天空分别被覆盖到低于1和5 mCrab的极限通量。我们的探测源目录包括403个天体，其中316个在时间平均天空图上超过了5σ检测阈值，其余的在不同的曝光子样本中被探测到。在已确定的来源中，219个是银河系（90个低质量x射线双星，76个高质量x射线双星，21个灾变变星，6个日冕活动恒星和其他类型），137个是河外星系，包括130个活动星系核（agn）和3个星系团。我们推导了agn和银河源的数通量函数。非blazar agn的logn - log关系是基于位于银河系纬度|b| > 5◦的68个源，在17 - 60 keV的能量带中，其通量高于S lim = 1.1 × 10 - 11 erg S - 1 cm - 2 (~ 0.8 mCrab)，具有较高的识别完整性。累积AGN数-通量函数可以用斜率为1.62±0.15的幂律来描述，在通量>.43 × 10−11 erg s−1 cm−2 （>mcrab）下，归一化为（5.7±0.7）× 10−3个源/度2。在17−60 keV时，通量高于S lim的agn占宇宙x射线背景的1%。我们发现了附近（<70 Mpc） agn空间分布的强烈不均匀性，这反映了局部宇宙的大尺度结构。
We present results of an all-sky hard X-ray survey based on almost four years of observations with the IBIS telescope onboard the INTEGRAL observatory. The dead time-corrected exposure of the survey is ∼33 Ms. Approximately 12% and 80% of the sky has been covered to limiting fluxes lower than 1 and 5 mCrab, respectively. Our catalog of detected sources includes 403 objects, 316 of which exceed a 5σ detection threshold on the time-averaged map of the sky, and the rest were detected in various subsamples of exposures. Among the identified sources, 219 are Galactic (90 low-mass X-ray binaries, 76 high-mass X-ray binaries, 21 cataclysmic variables, 6 coronally active stars, and other types) and 137 are extragalactic, including 130 active galactic nuclei (AGNs) and 3 galaxy clusters. We derived number-flux functions of AGNs and Galactic sources. The logN–logS relation of non-blazar AGNs is based on 68 sources located at Galactic latitudes |b| > 5 ◦ , where the survey is characterized by high identification completeness, with fluxes higher than S lim = 1.1 × 10 −11 erg s −1 cm −2 (∼0.8 mCrab) in the 17−60 keV energy band. The cumulative AGN number-flux function can be described by a power law with a slope of 1.62 ± 0.15 and normalization of (5.7 ± 0.7) × 10 −3 sources per deg 2 at fluxes >1.43 × 10 −11 erg s −1 cm −2 (>1 mCrab). Those AGNs with fluxes higher than S lim make up ∼1% of the cosmic X-ray background at 17−60 keV. We present evidence of strong inhomogeneity in the spatial distribution of nearby (<70 Mpc) AGNs, which reflects the large-scale structure in the local Universe.