arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1605.01422astro-ph.GAastro-ph.CO
收藏

在$z\sim3.5$上用MUSE揭示的最亮类星体周围无处不在的巨大Ly $α$星云

Ubiquitous giant Ly $α$ nebulae around the brightest quasars at $z\sim3.5$ revealed with MUSE

Elena Borisova, Sebastiano Cantalupo, Simon J. Lilly, Raffaella A. Marino, Sofia G. Gallego, Roland Bacon, Jeremy Blaizot, Nicolas Bouché, Jarle Brinchmann, C. … 展开作者

Elena Borisova, Sebastiano Cantalupo, Simon J. Lilly, Raffaella A. Marino, Sofia G. Gallego, Roland Bacon, Jeremy Blaizot, Nicolas Bouché, Jarle Brinchmann, C. Marcella Carollo, Joseph Caruana, Hayley Finley, Edmund C. Herenz, Johan Richard, Joop Schaye, Lorrie A. Straka, Monica L. Turner, Tanya Urrutia, Anne Verhamme, Lutz Wisotzki

摘要:

在$z\sim2$对星系际气体进行的直接Ly $α$成像最近揭示了类星体周围的巨大宇宙结构,例如蛞蝓星云(Cantalupo et al. 2014)。尽管它们的亮度很高,但在窄带和光谱调查中,这类系统的探测率不到10%,可能编码了类星体周围气体分布和类星体发射特性的关键信息。在这项研究中,我们使用的MUSE积分场仪器进行盲调查巨大的Ly $α$星云周围的17个明亮的射电安静类星体在$3<z<4$,不受以前的调查的限制。经过数据简化和专门开发的工具进行分析,我们发现每个类星体都被巨大的Ly $α$星云包围,其投影大小大于100物理kpc,在某些情况下,延伸到320 kpc。尽管星云的形态不同,但它们的圆形平均表面亮度轮廓看起来非常相似,并且与斜率为$\approx-1.8$的幂律一致。所有这些星云和蛞蝓星云的性质之间的相似性表明,所有系统都有类似的起源,明亮类星体周围的大部分气体可能处于相对“冷”(T $\sim$ 10 $^4$ K)和致密的阶段。此外,我们的研究结果表明,这种气体是普遍存在的至少50 kpc的明亮类星体在$3<z<4$独立的类星体的发射张开角,或扩展到200 kpc的类星体各向同性发射。

英文摘要:

Direct Ly $α$ imaging of intergalactic gas at $z\sim2$ has recently revealed giant cosmological structures around quasars, e.g. the Slug Nebula (Cantalupo et al. 2014). Despite their high luminosity, the detection rate of such systems in narrow-band and spectroscopic surveys is less than 10%, possibly encoding crucial information on the distribution of gas around quasars and the quasar emission properties. In this study, we use the MUSE integral-field instrument to perform a blind survey for giant Ly $α$ nebulae around 17 bright radio-quiet quasars at $3<z<4$ that does not suffer from most of the limitations of previous surveys. After data reduction and analysis performed with specifically developed tools, we found that each quasar is surrounded by giant Ly $α$ nebulae with projected sizes larger than 100 physical kpc and, in some cases, extending up to 320 kpc. The circularly averaged surface brightness profiles of the nebulae appear very similar to each other despite their different morphologies and are consistent with power laws with slopes $\approx-1.8$. The similarity between the properties of all these nebulae and the Slug Nebula suggests a similar origin for all systems and that a large fraction of gas around bright quasars could be in a relatively "cold" (T$\sim$10$^4$K) and dense phase. In addition, our results imply that such gas is ubiquitous within at least 50 kpc from bright quasars at $3<z<4$ independently of the quasar emission opening angle, or extending up to 200 kpc for quasar isotropic emission.

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。

↑