arXivDaily arXiv每日学术速递 周一至周五更新
北美退伍军人节(Veterans Day),12 日无更新
arXiv 1709.03522astro-ph.GA
收藏

用MUSE探测红移~3.5的暗星系候选体

Dark Galaxy Candidates at Redshift ~3.5 Detected with MUSE

Raffaella Anna Marino, Sebastiano Cantalupo, Simon J. Lilly, Sofia G. Gallego, Lorrie A. Straka, Elena Borisova, Roland Bacon, Jarle Brinchmann, C. Marcella Car… 展开作者

Raffaella Anna Marino, Sebastiano Cantalupo, Simon J. Lilly, Sofia G. Gallego, Lorrie A. Straka, Elena Borisova, Roland Bacon, Jarle Brinchmann, C. Marcella Carollo, Joseph Caruana, Simon Conseil, Thierry Contini, Catrina Diener, Hayley Finley, Hanae Inami, Floriane Leclercq, Sowgat Muzahid, Johan Richard, Joop Schaye, Martin Wendt, Lutz Wisotzki

摘要:

最近的理论模型表明,星系形成的早期阶段可能涉及一个星系富含气体但无法形成恒星的时期:“暗星系”阶段。在这里,我们报告的结果,我们的MUSE(多单元光谱探测器)调查的暗星系荧光照明类星体在$z>3$。与以前基于深窄带(NB)成像的研究相比,我们的积分场调查提供了一个几乎均匀的灵敏度覆盖在类星体周围的红移空间中的大体积,以及在每个位置的全光谱信息。由于这些独特的功能,我们能够使用在相同条件下获得的相同数据在类星体的大红移距离处构建控制样本。通过比较在类星体附近和对照样品中检测到的Ly $α$源的静止框架等效宽度(EW $_{0}$)分布,我们检测到高EW $_{0}$对象和类星体的位置之间存在明显的相关性。这种相关性在其他性质如Ly $α$光度或体积过密度中看不到,这表明至少这些物体中的一些可能具有荧光性质。其中,我们发现6个源没有连续对应物和EW $_{0}$限制大于$240\,\mathrmÅ$,是我们在$z>3.5$调查的暗星系的最佳候选人。这些暗星系候选者的体积密度和性质,包括推断的气体质量和恒星形成效率,与以前在NB调查中在$z\approx2.4$探测到的候选者相似。此外,如果最远的这些被类星体荧光照明,我们的结果也提供了一个下限的$t=60$兆年的类星体寿命。

英文摘要:

Recent theoretical models suggest that the early phase of galaxy formation could involve an epoch when galaxies are gas-rich but inefficient at forming stars: a "dark galaxy" phase. Here, we report the results of our MUSE (Multi Unit Spectroscopic Explorer) survey for dark galaxies fluorescently illuminated by quasars at $z>3$. Compared to previous studies which are based on deep narrow-band (NB) imaging, our integral field survey provides a nearly uniform sensitivity coverage over a large volume in redshift space around the quasars as well as full spectral information at each location. Thanks to these unique features, we are able to build control samples at large redshift distances from the quasars using the same data taken under the same conditions. By comparing the rest-frame equivalent width (EW$_{0}$) distributions of the Ly$α$ sources detected in proximity to the quasars and in control samples, we detect a clear correlation between the locations of high EW$_{0}$ objects and the quasars. This correlation is not seen in other properties such as Ly$α$ luminosities or volume overdensities, suggesting the possible fluorescent nature of at least some of these objects. Among these, we find 6 sources without continuum counterparts and EW$_{0}$ limits larger than $240\,\mathrmÅ$ that are the best candidates for dark galaxies in our survey at $z>3.5$. The volume densities and properties, including inferred gas masses and star formation efficiencies, of these dark galaxy candidates are similar to previously detected candidates at $z\approx2.4$ in NB surveys. Moreover, if the most distant of these are fluorescently illuminated by the quasar, our results also provide a lower limit of $t=60$ Myr on the quasar lifetime.

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。

↑