Cold dust emission from X-ray AGN in the SCUBA-2 Cosmology Legacy Survey: dependence on luminosity, obscuration and AGN activity
Cold dust emission from X-ray AGN in the SCUBA-2 Cosmology Legacy Survey: dependence on luminosity, obscuration and AGN activity
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SCUBA-2 宇宙学遗产巡天中 X 射线 AGN 的冷尘发射：对光度、遮光度和 AGN 活动的依赖
DOI：
10.1093/mnras/stv1881
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发表时间：
2015
影响因子：
4.8
通讯作者：
Banerji M
中科院分区：
文献类型：
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作者：
Banerji M
利用SCUBA-2宇宙学遗产巡天的新数据，研究了在102 deg 2COSMOS场中X射线选择的活动星系核（AGN）的850 μm辐射。我们发现了19850 μm的明亮X射线活动星系核，它位于0.89 ° 2的“高灵敏度”区域，通量密度为S850 = 4-10 mJy。这19颗活动星系核的红移和硬X射线光度涵盖了整个范围，分别为0.7 μ z <$3.5和43.2 μ log 10（LX）<$45。我们报道了一个非常有意义的堆积850 μm探测到的699 z> 1的硬X射线通量限制的粒子群AGN-S850 = 0.71 ± 0.08 mJy。我们探索了叠加的850 μm通量密度随红移的变化趋势，发现在探测的红移范围内，平均冷尘埃发射没有演变。对于第1类活动星系核，850 μm的叠加通量与硬X射线光度之间没有显著的相关性。然而，在2型活动星系核中，在高光度下，亚毫米波通量的叠加是2倍。当平均在所有的X射线光度，没有显着的差异被发现在堆叠的亚毫米波通量的类型1和类型2活动星系核以及活动星系核分离的基础上的X射线硬度比和光学-红外颜色。然而，当log 10（L2 − 10/erg s−1）> 44.4时，平均亚毫米波通量对光学到红外颜色的依赖性变得更加明显。我们认为，这些高光度活动星系核代表了一个过渡，从一个长期的合并驱动的演化阶段的星星形成率和吸积光度更紧密地耦合。将850 μm活动星系核的叠加通量与K波段选择的非活动星系核星系的质量匹配样本的叠加通量进行了比较。我们发现，在10.5 <log 10（M*/M *）<11.5时，非活动星系核的850 μm辐射通量比同等质量的第2类活动星系核高1.5-2倍。我们认为，这些差异是由于存在大量的尘埃，红色星暴星系在theK波段选择的非活动星系核样本，这是不存在的光学选择的目录覆盖面积较小。
We study the 850-μm emission in X-ray-selected active galactic nuclei (AGN) in the ∼2 deg2COSMOS field using new data from the SCUBA-2 Cosmology Legacy Survey. We find 19 850-μm bright X-ray AGN in a ‘high-sensitivity’ region covering 0.89 deg2with flux densities ofS850= 4–10 mJy. The 19 AGN span the full range in redshift and hard X-ray luminosity covered by the sample – 0.7 ≲z≲ 3.5 and 43.2 ≲ log10(LX) ≲ 45. We report a highly significant stacked 850-μm detection of a hard X-ray flux-limited population of 699z> 1 X-ray AGN –S850= 0.71 ± 0.08 mJy. We explore trends in the stacked 850-μm flux densities with redshift, finding no evolution in the average cold dust emission over the redshift range probed. For type 1 AGN, there is no significant correlation between the stacked 850-μm flux and hard X-ray luminosity. However, in type 2 AGN the stacked submillimeter flux is a factor of 2 higher at high luminosities. When averaging over all X-ray luminosities, no significant differences are found in the stacked submillimeter fluxes of type 1 and type 2 AGN as well as AGN separated on the basis of X-ray hardness ratios and optical-to-infrared colours. However, at log10(L2 − 10/erg s−1) > 44.4, dependences in average submillimeter flux on the optical-to-infrared colours become more pronounced. We argue that these high-luminosity AGN represent a transition from a secular to a merger-driven evolutionary phase where the star formation rates and accretion luminosities are more tightly coupled. Stacked AGN 850-μm fluxes are compared to the stacked fluxes of a mass-matched sample ofK-band-selected non-AGN galaxies. We find that at 10.5 <log10(M*/M⊙)<11.5, the non-AGN 850-μm fluxes are 1.5–2 times higher than in type 2 AGN of equivalent mass. We suggest these differences are due to the presence of massive dusty, red starburst galaxies in theK-band-selected non-AGN sample, which are not present in optically selected catalogues covering a smaller area.