COMPLETE INFRARED SPECTRAL ENERGY DISTRIBUTIONS OF MILLIMETER DETECTED QUASARS AT z > 5
COMPLETE INFRARED SPECTRAL ENERGY DISTRIBUTIONS OF MILLIMETER DETECTED QUASARS AT z > 5
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DOI：
10.1088/0004-637x/772/2/103
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发表时间：
2013-05
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影响因子：
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通讯作者：
C. Leipski;K. Meisenheimer;F. Walter;M.-A. Besel;H. Dannerbauer;Xiaohui Fan;M. Haas;U. Klaas
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文献类型：
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作者：
C. Leipski;K. Meisenheimer;F. Walter;M.-A. Besel;H. Dannerbauer;Xiaohui Fan;M. Haas;U. Klaas
本文对11个红移z > 5的类星体进行了Herschel远红外测光，这些类星体以前在1.2 mm处被探测到，我们对这些具有良好Herschel探测的天体在波长λrest = 0.1-400 μm范围内进行了全谱能量分布（SED）拟合。这些拟合揭示了除了由尘埃活动星系核（AGN）驱动的环的发射之外，还需要额外的远红外区分量。这个额外的FIR组件的温度为TFIR 40-60 K，光度为L 8 -1000 μm <$1013 L返（占辐射热FIR光度的25%-60%）。如果远红外区的尘埃排放是由于星星的形成，它将表明星星的形成速率超过每年1000个太阳质量。结果表明，在长波长（λrest ≤ 50 μm）下，活动星系核驱动的环面辐射的贡献可以忽略不计。这解释了以前的高红移类星体的FIR研究如何依赖于λobs <$350 μm的单分量拟合（地基）观测，达到了类似于我们完整的SED拟合的TFIR和LFIR值。将四个单独未检测到的源的Herschel数据叠加，揭示了PACS频带中的显著平均信号，但SPIRE中没有。与普通活动星系核模板相比，单个赫歇尔探测源的平均SED在近红外和中红外（MIR）发射方面显示出惊人的盈余。在UV/光学中匹配的两个平均SED（具有和不具有单独Herschel检测的源）之间的比较表明，对于这些对象，MIR发射的强度可能与FIR发射的强度相关。
We present Herschel far-infrared (FIR) photometry of 11 quasars at redshift z > 5 that have previously been detected at 1.2 mm. We perform full spectral energy distribution (SED) fits over the wavelength range λrest ∼ 0.1–400 μm for those objects with good Herschel detections. These fits reveal the need for an additional FIR component besides the emission from a dusty active galactic nucleus (AGN)-powered torus. This additional FIR component has temperatures of TFIR ∼ 40–60 K with luminosities of L8–1000 μm ∼ 1013 L☉ (accounting for 25%–60% of the bolometric FIR luminosity). If the FIR dust emission is due to star formation it would suggest star formation rates in excess of 1000 solar masses per year. We show that at long wavelengths (λrest ≳ 50 μm) the contribution of the AGN-powered torus emission is negligible. This explains how previous FIR studies of high-redshift quasars that relied on single-component fits to (ground-based) observations at λobs ≳ 350 μm reached TFIR and LFIR values similar to our complete SED fits. Stacking the Herschel data of four individually undetected sources reveals a significant average signal in the PACS bands but not in SPIRE. The average SED of sources with individual Herschel detections shows a striking surplus in near- and mid-infrared (MIR) emission when compared to common AGN templates. The comparison between two average SEDs (sources with and without individual Herschel detections) matched in the UV/optical indicates that for these objects the strength of the MIR emission may correlate with the strength of the FIR emission.