Long-term NIR variability in the UKIDSS Ultra Deep Survey: a new probe of AGN activity at high redshift
Long-term NIR variability in the UKIDSS Ultra Deep Survey: a new probe of AGN activity at high redshift
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DOI：
10.1093/mnras/staa381
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发表时间：
2020-02
影响因子：
4.8
通讯作者：
E. Elmer;O. Almaini;M. Merrifield;W. Hartley;D. Maltby;A. Lawrence;I. Botti;P. Hirst
中科院分区：
文献类型：
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作者：
E. Elmer;O. Almaini;M. Merrifield;W. Hartley;D. Maltby;A. Lawrence;I. Botti;P. Hirst
我们提出了第一次尝试选择活动星系核（AGN）使用长期近红外（NIR）的变化。通过分析UKIRT红外深空巡天（UKIDSS）超深巡天（最深的近红外巡天超过101 ° 2）中所有星系的K波段光变曲线，我们分离出了393个可变活动星系核候选者。与其他选择技术的比较表明，只有一半的变量源也选择使用深钱德拉X射线成像或红外阵列相机（IRAC）的颜色选择，这表明使用近红外变化可以定位AGN错过了更标准的选择技术。特别是，我们发现，长期的近红外光谱的变化识别AGN在低光度和低恒星质量的宿主星系，其中许多出现相对X射线安静。
We present the first attempt to select active galactic nuclei (AGN) using long-term near-infrared (NIR) variability. By analysing the K-band light curves of all the galaxies in the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra Deep Survey, the deepest NIR survey over ∼1 deg2, we have isolated 393 variable AGN candidates. A comparison to other selection techniques shows that only half of the variable sources are also selected using either deep Chandra X-ray imaging or Infrared Array Camera (IRAC) colour selection, suggesting that using NIR variability can locate AGN that are missed by more standard selection techniques. In particular, we find that long-term NIR variability identifies AGN at low luminosities and in host galaxies with low stellar masses, many of which appear relatively X-ray quiet.