arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2101.00764astro-ph.GA
收藏

类星体宿主星系中致密分子气体的分布

Compact Molecular Gas Distribution in Quasar Host Galaxies

Molina, J., Wang, R., Shangguan, J., Ho, L. C., Bauer, F. E., Treister, E., Shao, Y

摘要:

利用阿塔卡玛大型毫米/亚毫米阵列CO(2-1)观测了6个低红移帕洛玛-格林类星体,在kpc尺度上研究了它们的宿主星系分子气体的分布和运动学。虽然类星体的分子气体含量、分子气体比例和恒星形成速率与邻近的大质量恒星形成星系相似,但类星体宿主星系拥有异常致密的盘状分子气体分布,其中值半光半径为1.8 kpc,分子气体质量表面密度为$\gtrsim 22$ $M_\odot$ pc $^{-2}$。虽然分子气体的整体速度场主要由规则旋转到大半径,旋转速度与速度的色散比$\gtrsim 9$,核区域显示大量的运动学复杂性与小尺度的气体分布的子结构。倾斜环分析表明,运动学和光度位置角平均不对齐$\sim 34 \pm 26^\circ$,并提供了运动学扭曲的证据。这些观测结果提供了诱人的线索,详细的物理条件的周围环境的积极吸积超大质量黑洞。

英文摘要:

We use Atacama Large Millimeter/submillimeter Array CO(2-1) observations of six low-redshift Palomar-Green quasars to study the distribution and kinematics of the molecular gas of their host galaxies at kpc-scale resolution. While the molecular gas content, molecular gas fraction, and star formation rates are similar to those of nearby massive, star-forming galaxies, the quasar host galaxies possess exceptionally compact, disky molecular gas distributions with a median half-light radius of 1.8 kpc and molecular gas mass surface densities $\gtrsim 22$ $M_\odot$pc$^{-2}$. While the overall velocity field of the molecular gas is dominated by regular rotation out to large radii, with rotation velocity-to-velocity dispersion ratio $\gtrsim 9$, the nuclear region displays substantial kinematic complexity associated with small-scale substructure in the gas distribution. A tilted-ring analysis reveals that the kinematic and photometric position angles are misaligned on average by $\sim 34 \pm 26^\circ$, and provides evidence of kinematic twisting. These observations provide tantalizing clues to the detailed physical conditions of the circumnuclear environments of actively accreting supermassive black holes.

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。

↑