arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2404.03576astro-ph.GA
收藏

$z>4$ 处微弱红色活动星系核的兴起:JWST 河外遗产场中的小红点样本

The Rise of Faint, Red AGN at $z>4$: A Sample of Little Red Dots in the JWST Extragalactic Legacy Fields

Dale D. Kocevski, Steven L. Finkelstein, Guillermo Barro, Anthony J. Taylor, Antonello Calabrò, Brivael Laloux, Johannes Buchner, Jonathan R. Trump, Gene C. K. … 展开作者

Dale D. Kocevski, Steven L. Finkelstein, Guillermo Barro, Anthony J. Taylor, Antonello Calabrò, Brivael Laloux, Johannes Buchner, Jonathan R. Trump, Gene C. K. Leung, Guang Yang, Mark Dickinson, Pablo G. Pérez-González, Fabio Pacucci, Kohei Inayoshi, Rachel S. Somerville, Elizabeth J. McGrath, Hollis B. Akins, Micaela B. Bagley, Laura Bisigello, Rebecca A. A. Bowler, Adam Carnall, Caitlin M. Casey, Yingjie Cheng, Nikko J. Cleri, Luca Costantin, Fergus Cullen, Kelcey Davis, Callum T. Donnan, James S. Dunlop, Richard S. Ellis, Henry C. Ferguson, Seiji Fujimoto, Adriano Fontana, Mauro Giavalisco, Andrea Grazian, Norman A. Grogin, Nimish P. Hathi, Michaela Hirschmann, Marc Huertas-Company, Benne W. Holwerda, Garth Illingworth, Stéphanie Juneau, Jeyhan S. Kartaltepe, Anton M. Koekemoer, Wenxiu Li, Ray A. Lucas, Dan Magee, Charlotte Mason, Derek J. McLeod, Ross J. McLure, Lorenzo Napolitano, Casey Papovich, Nor Pirzkal, Giulia Rodighiero, Paola Santini, Stephen M. Wilkins, L. Y. Aaron Yung

AI总结:

基于JWST河外遗产场数据,构建341个小红点样本,发现其数量远超X射线/紫外选AGN,并首次探测到X射线LRDs,证实其为中等遮蔽AGN,部分显示蓝移吸收线,暗示中心引擎存在外流。

摘要:

我们利用 CEERS、PRIMER、JADES、UNCOVER 和 NGDEEP 巡天的数据,呈现了一个包含 341 个“小红点”(LRDs)的样本,其红移范围跨越 $z\sim2-11$。与以往使用颜色指数来识别 LRDs 的方法不同,我们采用连续谱斜率拟合,利用移动的带通滤波器来采样巴尔默断裂蓝侧和红侧的相同静止系辐射。这使得我们能够在更宽的红移范围内探测到 LRDs,并减少来自具有强断裂但缺乏上升红色连续谱的星系的污染。我们样本的红移分布在 $z<8$ 处增加,然后在 $z\sim4.5$ 处迅速下降,这可能将这些源的出现与星系在该时期经历的由内而外的增长联系起来。我们发现,在 $z\sim5-7$ 处,LRDs 的数量比 X 射线和紫外选择的 AGN 多约 1 dex。在我们的样本中,我们识别出了首批两个 X 射线探测到的 LRDs。X 射线光谱分析证实这些 AGN 具有中等程度的遮蔽,其 $\log\\,(N_{\rm H}/{\rm cm}^{2}$) 分别为 $23.3^{+0.4}_{-1.3}$ 和 $22.72^{+0.13}_{-0.16}$。我们的分析揭示,红化的 AGN 辐射主导了它们的静止光学光,而静止紫外辐射则来自其宿主星系。我们还展示了来自 RUBIES 巡天的 17 个 LRDs 的 NIRSpec 观测,这些观测显示出与 AGN 活动一致的宽发射线。对于 F444W<26.5 的源,我们样本的确认 AGN 比例为 71%。此外,我们在三个 LRDs 的光谱中发现了蓝移的巴尔默吸收特征,这表明存在从这些微弱红色 AGN 的中心引擎附近流出的高密度、低电离气体。

英文摘要:

We present a sample of 341 "little red dots" (LRDs) spanning the redshift range $z\sim2-11$ using data from the CEERS, PRIMER, JADES, UNCOVER and NGDEEP surveys. Unlike past use of color indices to identify LRDs, we employ continuum slope fitting using shifting bandpasses to sample the same rest-frame emission blueward and redward of the Balmer break. This enables the detection of LRDs over a wider redshift range and with less contamination from galaxies with strong breaks that otherwise lack a rising red continuum. The redshift distribution of our sample increases at $z<8$ and then undergoes a rapid decline at $z\sim4.5$, which may tie the emergence of these sources to the inside-out growth that galaxies experience during this epoch. We find that LRDs are $\sim1$ dex more numerous than X-ray and UV selected AGN at z~5-7. Within our sample, we have identified the first two X-ray detected LRDs. An X-ray spectral analysis confirms that these AGN are moderately obscured with $\log\,(N_{\rm H}/{\rm cm}^{2}$) of $23.3^{+0.4}_{-1.3}$ and $22.72^{+0.13}_{-0.16}$. Our analysis reveals that reddened AGN emission dominates their rest-optical light, while the rest-UV originates from their host galaxies. We also present NIRSpec observations from the RUBIES survey of 17 LRDs that show broad emission lines consistent with AGN activity. The confirmed AGN fraction of our sample is 71\% for sources with F444W<26.5. In addition, we find three LRDs with blue-shifted Balmer absorption features in their spectra, suggesting an outflow of high-density, low-ionization gas from near the central engine of these faint, red AGN.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑