The dust emission of high-redshift quasars
The dust emission of high-redshift quasars
复制标题
高红移类星体的尘埃排放
DOI：
10.1088/1742-6596/372/1/012037
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Meisenheimer
中科院分区：
文献类型：
--
作者：
Leipski;Meisenheimer
在高红移（z> 5）类星体中探测到的强大的近红外辐射表明，在非常早期的宇宙中，非常热的尘埃也存在于活动核附近。一些高红移天体甚至在静止系近红外光谱中显示出比活动星系核更局部的光谱能量分布（SED）模板显著的过量发射。为了测试这是否是非常高的光度或红移的结果，我们从最新的SDSS类星体目录中结合来自WISE初步数据发布的几个红移和光度箱的MIR数据构建平均SED。将这些平均SED与z> 5类星体的大样本进行比较，我们无法确定在2.5< z <$6和10 45< νL ν（1350 π）<$10 47 erg/s区域内，近红外光谱斜率随光度或红移的任何显著趋势。除了近红外区域，我们的赫歇尔和斯皮策测光组合提供了z> 5类星体相同样本的全红外SED覆盖。这些观测结果揭示了7个天体的强远红外辐射（L FIR 10 13 L FIR），可能表明恒星的形成速率为每年数千个太阳质量。远红外区的过量辐射具有不寻常的高温（T = 65 K），这与通常在较低红移（T = 45 K）的研究中预期的温度形成对比。目前正在对这些物体进行更详细的调查。
The detection of powerful near-infrared emission in high redshift (z> 5) quasars demonstrates that very hot dust is present close to the active nucleus also in the very early universe. A number of high-redshift objects even show significant excess emission in the rest frame NIR over more local AGN spectral energy distribution (SED) templates. In order to test if this is a result of the very high luminosities or redshifts, we construct mean SEDs from the latest SDSS quasar catalogue in combination with MIR data from the WISE preliminary data release for several redshift and luminosity bins. Comparing these mean SEDs with a large sample of z> 5 quasars we could not identify any significant trends of the NIR spectral slope with luminosity or redshift in the regime 2.5< z≲ 6 and 10 45< νL ν (1350Å)≲ 10 47 erg/s. In addition to the NIR regime, our combined Herschel and Spitzer photometry provides full infrared SED coverage of the same sample of z> 5 quasars. These observations reveal strong FIR emission (L FIR≳ 10 13 L⊙) in seven objects, possibly indicating star-formation rates of several thousand solar masses per year. The FIR excess emission has unusally high temperatures (T∼ 65K) which is in contrast to the temperature typically expected from studies at lower redshift (T∼ 45K). These objects are currently being investigated in more detail.
影响因子：
64.8
作者：
F. Walter;D. Riechers;P. Cox;R. Neri;C. Carilli;F. Bertoldi;A. Weiss;R. Maiolino
通讯作者：
F. Walter;D. Riechers;P. Cox;R. Neri;C. Carilli;F. Bertoldi;A. Weiss;R. Maiolino