AEGIS: The Environment of X-Ray Sources at z ≈ 1
AEGIS: The Environment of X-Ray Sources at z ≈ 1
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AEGIS：z ≈ 1 处的 X 射线源环境
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
A. Coil
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文献类型：
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作者：
A. Georgakakis;K. Nandra;E. Laird;M. Cooper;B. Gerke;J. Newman;D. Croton;M. Davis;S. Faber;A. Coil
我们探索环境的z 1活动星系核使用的样本53光谱确定的X射线源在全波长扩展的增长带国际调查。我们量化的局部密度在附近的X射线源通过测量投影的表面密度光谱确定的光学星系的半径内定义的第三个最近的邻居。我们的主要结果是，X射线选择的活动星系核在z = 1，避免在99.89%的置信水平下的密度不足的区域。此外，虽然我们发现，总人口共享相同的（丰富的）环境与光学星系的类似的U - B和MB，也有初步的证据（96%），活动星系与蓝色（U - B 1）居住在更密集的环境相比，光学星系。我们认为，上述结果是大质量星系的下落的结果，能够容纳超大质量黑洞在其中心，与可用的冷气库，AGN活动的燃料。在z = 1时，在稠密区域中发现这种系统的比例越来越大。
We explore the environment of z ≈ 1 AGNs using a sample of 53 spectroscopically identified X-ray sources in the All-Wavelength Extended Groth Strip International Survey. We quantify the local density in the vicinity of an X-ray source by measuring the projected surface density of spectroscopically identified optical galaxies within a radius defined by the third-nearest neighbor. Our main result is that X-ray-selected AGNs at z ≈ 1 avoid underdense regions at a 99.89% confidence level. Moreover, although we find that the overall population shares the same (rich) environment with optical galaxies of the similar U - B and MB, there is also tentative evidence (96%) that AGNs with blue colors (U - B ≲ 1) reside in denser environments compared to optical galaxies. We argue that the results above are a consequence of the whereabouts of massive galaxies capable of hosting supermassive black holes at their centers, with available cold-gas reservoirs, the fuel for AGN activity. At z ≈ 1 an increasing fraction of such systems is found in dense regions.