论文标题
超级iv。 Alma揭示的活性银河核宿主的CO（J = 3-2）
SUPER IV. CO(J=3-2) properties of active galactic nucleus hosts at cosmic noon revealed by ALMA
论文作者
论文摘要
人们认为，通过调节恒星形成活性，AGN的反馈是塑造其宿主星系生命周期的关键。因此，要了解AGN对恒星形成的影响，必须从哪个恒星形成的分子气体中追踪分子气。在本文中，我们介绍了AGN宿主在Z〜2处的CO特性的首次系统研究，用于27 X射线选定的样本，其中跨越了两个数量级的AGN强度亮度（LBOL = 10^44.7-10^46.9 erg/s），使用ALMA频段3的CO（3-2）propition（3-2）propportion（3-2）的范围（3-2）的范围搜索ANGILLE（3-2）的范围。宿主星系，我们将AGN与PHIBS的非活性（即非AGN）星系进行了比较。恒星质量和SFR的功能，以及LCO（3-2）/M*的比例（对气体分数的代理）在LCO（3-2）-LFIR和LCO（3-2）中显示出统计上一致的趋势。 2-3的水平当我们关注结果更好的限制的参数子集，并且平均LCO（3-2）/m*的分布，即使是通过保守地假设相同的激发因子R31，我们会发现AGN中的分子气体较低，并假设较高的R31会使我们的效果变得更加差异。可以加热，激发，解离和/或耗尽宿主星系的气体（删节）。
Feedback from AGN is thought to be key in shaping the life cycle of their host galaxies by regulating star-formation activity. Therefore, to understand the impact of AGN on star formation, it is essential to trace the molecular gas out of which stars form. In this paper we present the first systematic study of the CO properties of AGN hosts at z~2 for a sample of 27 X-ray selected AGN spanning two orders of magnitude in AGN bolometric luminosity (Lbol= 10^44.7-10^46.9 erg/s) by using ALMA Band 3 observations of the CO(3-2) transition (~1" angular resolution). To search for evidence of AGN feedback on the CO properties of the host galaxies, we compared our AGN with a sample of inactive (i.e., non-AGN) galaxies from the PHIBSS survey with similar redshift, stellar masses, and SFRs. We used the same CO transition as a consistent proxy for the gas mass for the two samples in order to avoid systematics involved when assuming conversion factors. By adopting a Bayesian approach to take upper limits into account, we analyzed CO luminosities as a function of stellar masses and SFRs, as well as the ratio LCO(3-2)/M* (proxy for the gas fraction). The two samples show statistically consistent trends in the LCO(3-2)-Lfir and LCO(3-2)-M* planes. However, there are indications that AGN feature lower CO(3-2) luminosities (0.4-0.7 dex) than inactive galaxies at the 2-3sigma level when we focus on the subset of parameters where the results are better constrained and on the distribution of the mean LCO(3-2)/M*. Therefore, even by conservatively assuming the same excitation factor r31, we would find lower molecular gas masses in AGN, and assuming higher r31 would exacerbate this difference. We interpret our result as a hint of the potential effect of AGN activity (e.g., radiation and outflows), which may be able to heat, excite, dissociate, and/or deplete the gas reservoir of the host galaxies. (abridged)
