论文标题
探测高红移弱排放线类星体的性质：带有星爆宿主银河系的年轻类星体
Probing the Nature of High Redshift Weak Emission Line Quasars: A Young Quasar with a Starburst Host Galaxy
论文作者
论文摘要
我们介绍了PSO J083.8371+11.8482的发现，这是一条弱排放线，$ z = 6.3401 $的极端星形形成率。该类星体是从Pan-Starrs1，UHS和不明智的光度数据中选择的。 Gemini/gnirs光谱随访表明基于MGII的黑洞质量为$ M_ \ MATHRM {BH} = \ left（2.0^{+0.7} _ { - 0.4} \ right）\ times10^9〜m_ $ l_ \ mathrm {bol}/l_ \ mathrm {edd} = 0.5^{+0.1} _ { - 0.2} $，与在$ z \ gtrsim6 $上积极积累超大型黑洞（SMBH）。 HST成像设定了对镜头增强的强大限制，对明显的发射没有相关的影响。还将类星体视为纯点源，没有额外的发射分量。宽线区域（BLR）发射本质上是弱的，不太可能是由中间吸收器引起的。我们发现了EW的休息框架等效宽度（ly $α$+NV）$ = 5.7 \ pm0.7 $ angstrom，ew（civ）$ \ leq5.8 $ angstrom（3-Sigma上限）和ew（mgii）$ = 8.7 \ pm0.7 $ angstrom。一个小的接近区域大小（$ r_ \ mathrm {p} = 1.2 \ pm0.4 $ pmpc）表示，从上一quasar apep ighition起，寿命仅为$ t_ \ mathrm {q} = 10^{3.4 \ pm0.7} $年。 Alma显示出具有轻度速度梯度的扩展[CII]发射。推断的远红外光度（$ l_ \ mathrm {fir} =（1.2 \ pm0.1）\ times10^{13} \，l_ \ odot $）是所有已知的Quasar主机中最高的$ z \ gtrsim6 $之一。灰尘和[CII]排放对SFR $ = 900-4900〜M_ \ ODOT \，\ MATHRM {yr^{ - 1}} $的恒星形成速率构成了约束，类似于超薄的红外星系。考虑到观察到的类星体寿命和BLR形成时间尺度，类星体光谱中的弱线轮廓很可能是由于BLR引起的，BLR尚未完全形成，而不是由于重力镜头或由于超级埃德丁顿的超级连续性而促进连续体。
We present the discovery of PSO J083.8371+11.8482, a weak emission line quasar with extreme star formation rate at $z=6.3401$. This quasar was selected from Pan-STARRS1, UHS, and unWISE photometric data. Gemini/GNIRS spectroscopy follow-up indicates a MgII-based black hole mass of $M_\mathrm{BH}=\left(2.0^{+0.7}_{-0.4}\right)\times10^9~M_\odot$ and an Eddington ratio of $L_\mathrm{bol}/L_\mathrm{Edd}=0.5^{+0.1}_{-0.2}$, in line with actively accreting supermassive black hole (SMBH) at $z\gtrsim6$. HST imaging sets strong constraint on lens-boosting, showing no relevant effect on the apparent emission. The quasar is also observed as a pure point-source with no additional emission component. The broad line region (BLR) emission is intrinsically weak and not likely caused by an intervening absorber. We found rest-frame equivalent widths of EW(Ly$α$+NV) $=5.7\pm0.7$ Angstrom, EW(CIV) $\leq5.8$ Angstrom (3-sigma upper limit), and EW(MgII) $=8.7\pm0.7$ Angstrom. A small proximity zone size ($R_\mathrm{p}=1.2\pm0.4$ pMpc) indicates a lifetime of only $t_\mathrm{Q}=10^{3.4\pm0.7}$ years from the last quasar phase ignition. ALMA shows extended [CII] emission with a mild velocity gradient. The inferred far-infrared luminosity ($L_\mathrm{FIR}=(1.2\pm0.1)\times10^{13}\,L_\odot$) is one of the highest among all known quasar hosts at $z\gtrsim6$. Dust and [CII] emissions put a constraint on the star formation rate of SFR $=900-4900~M_\odot\,\mathrm{yr^{-1}}$, similar to that of hyper-luminous infrared galaxy. Considering the observed quasar lifetime and BLR formation timescale, the weak-line profile in the quasar spectrum is most likely caused by a BLR which is not yet fully formed rather than continuum boosting by gravitational lensing or a soft continuum due to super-Eddington accretion.
