本文介绍了利用AKARI红外卫星上的红外照相机（IRC）在$z=3.91$上拍摄的引力作用下类星体APM 08279+5255的静止坐标系光学/近红外光谱。所观察到的连续谱由两个部分组成;一个主要的光学波长是来自中心源的直射光，一个主要的近红外波长是来自环核区域热尘埃发射的热发射。热辐射很好地代表了热尘埃在T ~ 1300 K的光学厚辐射，τ（2 μ m）> 2，视质量M（热）> 10M_sun。因此，我们的观测直接探测到了APM 08279+5255中热尘埃的光学厚度区域。在3.2、6.3和9.3 μ m处清晰地检测到H_α（0.656 μ m）、Pa_α（1.875 μ m）和Pa_β（1.282 μ m）的HI复合线。光电离模式模拟结果表明，APM 08279+5255具有BLR（宽线区）云，其特征为：气体密度为log n_{H} ~ 12- 14，宽线区为log U ~ -2 - -6 $ for the ionization parameter, and E(B-V) ~ 0.3-0.6$。因此，光学厚排放的热尘埃支持一个想法的非球形分布的尘埃附近的中央源，与活动星系核模型与尘埃环面一致。这些HI谱线的热尘温度和通量比与在低红移类星体中观测到的相似。HI谱线有明显的时间变化，这可能是由中心源亮度的变化引起的。
英文摘要：
We present rest-frame optical/near-infrared spectra of the gravitationally lense d quasar APM 08279+5255 at $z=3.91$ that has been taken using the Infrared Camera (IRC) onboard the AKARI infrared satellite. The observed continuum consists of two components; a power-law component dominating optical wavelengths which is the direct light from the central source and thermal emission dominating near-infrared wavelengths which is attributed to the emission from hot dust in the circumnuclear region. The thermal emission well represents optically thick emission by hot dust at T ~ 1300K with tau(2micron)> 2 and apparent mass, M(hot) >10 M_sun. Thus, our observations directly detected the optically thick region of hot dust in APM 08279+5255. HI recombination lines of H_alpha(0.656micron), Pa_alpha(1.875micron), and Pa_beta(1.282micron) are clearly detected at 3.2, 6.3, and 9.3 micron. Simulations with the photoionization models suggest that APM 08279+5255 has BLR(Broad Line Region) clouds characterized by log n_{H} ~ 12- 14 for the gas density, log U ~ -2 - -6$ for the ionization parameter, and E(B-V) ~ 0.3-0.6$for the broad line region. Thus, optically thick emission of hot dust support an idea on non-spherical distribution of dust near the central source, consistent with the Active Galactic Nuclei model with the dust torus. The temperature of hot dust and flux ratios of these HI lines are similar to those observed in low-redshift quasars. There are significant time-variations in the HI lines, which are probably caused by variations in the brightness of the central source.
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AKARI Observation of the North Ecliptic Pole (NEP) Supercluster at z = 0.087: mid-infrared view of transition galaxies
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We present the first detailed analysis of three extragalactic fields (IRAC Dark Field, ELAIS-N1, ADF-S) observed by the infrared satellite, AKARI, using an optimised data analysis toolkit specifically for the processing of extragalactic point sources. The InfraRed Camera (IRC) on AKARI complements the Spitzer space telescope via its comprehensive coverage between 8-24 microns filling the gap between the Spitzer IRAC and MIPS instruments. Source counts in the AKARI bands at 3.2, 4.1, 7, 11, 15 and 18 microns are presented. At near-infrared wavelengths, our source counts are consistent with coun…
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Observations of the Near- to Mid-Infrared Unidentified Emission Bands in the Interstellar Medium of the Large Magellanic Cloud
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