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arXiv 2202.01738astro-ph.GA
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用MUSE观测到的M83中的恒星反馈-- I.概述,对恒星和气体运动学的前所未有的看法以及流出气体的证据

Stellar feedback in M83 as observed with MUSE -- I. Overview, an unprecedented view of the stellar and gas kinematics and evidence of outflowing gas

Lorenza Della Bruna, Angela Adamo, Philippe Amram, Erik Rosolowsky, Christopher Usher, Mattia Sirressi, Andreas Schruba, Eric Emsellem, Adam Leroy, Arjan Bik, W… 展开作者

Lorenza Della Bruna, Angela Adamo, Philippe Amram, Erik Rosolowsky, Christopher Usher, Mattia Sirressi, Andreas Schruba, Eric Emsellem, Adam Leroy, Arjan Bik, William P. Blair, Anna F. McLeod, Göran Östlin, Florent Renaud, Carmelle Robert, Laurie Rousseau-Nepton, Linda J. Smith

摘要:

我们提出了一个大的VLT/MUSE马赛克(3.8 × 3.8千秒差距)附近的旋涡星系M83,空间分辨率约20秒差距。我们得到了恒星和电离气体的运动学,并与ALMA CO(2-1)的分子气体运动学进行了比较。我们将电离气体分为HII区和扩散电离气体(DIG),并确定了来自DIG的Ha光度分数(f_DIG)。我们观察到,恒星和气体跟踪银河系盘旋转,以及快速旋转的核组件,可能连接到长期的过程驱动的银河酒吧。在气体运动学中,我们观察到原子核以东的气流,相对于圆盘发生了红移。该流被一个扩展的电离气体区域所包围,该电离气体区域具有增强的速度分散和高电离状态,这在很大程度上与被慢冲击电离一致。我们解释这一功能的叠加盘和平面外层的DIG,或作为一个酒吧驱动的冲击气体流入。一个双高斯分量拟合的Ha线也揭示了存在一个核的双锥结构,其对称轴是垂直于酒吧。这两个锥沿着视线出现蓝移和红移,并突出具有Ha发射,其与盘的分离高达200 km s-1,以及高速色散~80-200 km s-1。在锥体的远端,我们观察到气体与被冲击电离一致。这些特征以前从未在M83中观察到过;我们假设它们是在追踪一个恒星暴驱动的外流,冲击周围的ISM。最后,我们在我们的视野中获得f_DIG ~ 13%。我们检查发射的HII地区和DIG的“BPT”图,发现在HII地区的光电离占99.8%的哈通量,而DIG有混合贡献的光电离(94.9%)和冲击(5.1%)。[删节]

英文摘要:

We present a large VLT/MUSE mosaic (3.8 x 3.8 kpc) of the nearby spiral galaxy M83, with a spatial resolution ~20 pc. We obtained the kinematics of the stars and ionised gas, and compared them with molecular gas kinematics from ALMA CO(2-1). We separated the ionised gas into HII regions and diffuse ionised gas (DIG) and determined the fraction of Ha luminosity originating from the DIG (f_DIG). We observe that both stars and gas trace the galactic disk rotation, as well as a fast-rotating nuclear component, likely connected to secular processes driven by the galactic bar. In the gas kinematics, we observe a stream east of the nucleus, redshifted with respect to the disk. The stream is surrounded by an extended ionised gas region with enhanced velocity dispersion and a high ionisation state, which is largely consistent with being ionised by slow shocks. We interpret this feature as either the superposition of the disk and an extraplanar layer of DIG, or as a bar-driven inflow of shocked gas. A double Gaussian component fit to the Ha line also reveals the presence of a nuclear biconic structure whose axis of symmetry is perpendicular to the bar. The two cones appear blue- and redshifted along the line of sight and stand out for having an Ha emission separated by up to 200 km s-1 from that of the disk, and a high velocity dispersion ~80-200 km s-1. At the far end of the cones, we observe that the gas is consistent with being ionised by shocks. These features had never been observed before in M83; we postulate that they are tracing a starburst-driven outflow shocking into the surrounding ISM. Finally, we obtain f_DIG ~ 13% in our field of view. We inspect the emission of the HII regions and DIG in `BPT' diagrams, finding that in HII regions photoionisation accounts for 99.8% of the Ha flux, whereas the DIG has a mixed contribution from photoionisation (94.9%) and shocks (5.1%). [abridged]

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。

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