The Fornax 3D project: dust mix and gas properties in the centre of early-type galaxy FCC 167
The Fornax 3D project: dust mix and gas properties in the centre of early-type galaxy FCC 167
复制标题
DOI：
10.1051/0004-6361/201834465
复制
发表时间：
2018-12
影响因子：
6.5
通讯作者：
S. Viaene;M. Sarzi;N. Zabel;L. Coccato;E. Corsini;T. Davis;P. D. Vis;P. Zeeuw;J. Falc'on-Barroso;D. Gadotti;E. Iodice;M. Lyubenova;R. McDermid;L. Morelli;B. Nedelchev;F. Pinna;Thomas William Spriggs;G. Ven
中科院分区：
文献类型：
--
作者：
S. Viaene;M. Sarzi;N. Zabel;L. Coccato;E. Corsini;T. Davis;P. D. Vis;P. Zeeuw;J. Falc'on-Barroso;D. Gadotti;E. Iodice;M. Lyubenova;R. McDermid;L. Morelli;B. Nedelchev;F. Pinna;Thomas William Spriggs;G. Ven
星系不断地重新处理它们的星际物质。因此，我们可以预期，遵循不同演化路径的星系中的尘埃颗粒性质会发生变化。确定星系固有的尘埃颗粒混合有助于重建其进化史。早期类型的星系在其中心区域偶尔会显示出规则的尘埃带。由于它们的星体的几何结构和组成相对简单，这些星系非常适合将尘埃混合的变化从几何效应中分离出来。因此，我们模拟了这样一个星系的各个组成部分(FCC 167)。我们重建了它的近代史，并调查了尘埃小道可能的命运。来自缪斯和阿塔卡马大毫米/亚毫米阵列(ALMA)的观测揭示了一种嵌套的星际介质结构。一个电离气体圆盘遍布FCC 167的中心区域，包括那些被主要尘埃通道占据的区域。在尘埃通道的内部，我们还发现了一个冷分子气体的圆盘/环，在那里恒星正在形成，而HII区对电离气体的发射做出了贡献。在更远的地方，气体电离指向一个活跃的星系核，并从其周围的电离和分子储存库向中央超大质量黑洞提供燃料。观测约束和辐射传输模型表明，尘埃和气体呈环状分布，尘埃混合物缺乏小颗粒。在热气中溅射产生的尘埃破坏时间很短，我们得出结论，尘埃必须具有很强的自屏蔽性和块状，否则很快就会被侵蚀和消失。我们的发现表明，对单个系统的详细分析可以补充尘埃通道ETG的统计研究。
Galaxies continuously reprocess their interstellar material. We can therefore expect changing dust grain properties in galaxies that have followed different evolutionary pathways. Determining the intrinsic dust grain mix of a galaxy helps in reconstructing its evolutionary history. Early-type galaxies occasionally display regular dust lanes in their central regions. Owing to the relatively simple geometry and composition of their stellar bodies, these galaxies are ideal to disentangle dust mix variations from geometric effects. We therefore modelled the various components of such a galaxy (FCC 167). We reconstructed its recent history and investigated the possible fate of the dust lane. Observations from MUSE and the Atacama Large Millimeter/submillimeter Array (ALMA) reveal a nested interstellar medium structure. An ionised-gas disc pervades the central regions of FCC 167, including those occupied by the main dust lane. Inward of the dust lane, we also find a disc/ring of cold molecular gas where stars are forming and HII regions contribute to the ionised-gas emission. Further in, the gas ionisation points towards an active galactic nucleus and the fuelling of a central supermassive black hole from its surrounding ionised and molecular reservoir. Observational constraints and radiative transfer models suggest the dust and gas are distributed in a ring-like geometry and the dust mix lacks small grains. The derived dust destruction timescales from sputtering in hot gas are short, and we conclude that the dust must be strongly self-shielding and clumpy or will quickly be eroded and disappear. Our findings show how detailed analyses of individual systems can complement statistical studies of dust-lane ETGs.