超新星和辐射反馈对活动星系核的遮蔽作用
Obscuring fraction of active galactic nuclei implied by supernova and radiative feedbacks
摘要：
通过考虑核星暴的超新星反馈和活动星系核辐射压力的各向异性效应，研究了环核盘的遮蔽结构。我们假设中心超大质量黑洞（SMBH）的质量吸积是由CND内部SN驱动的湍流触发的，并探讨了CND的结构如何依赖于BH质量（$M_{\rm BH}$）和活动星系核亮度（$L_{\rm AGN}$）.我们发现，遮蔽分数（$f_{\rm obs}$）在爱丁顿光度（$L_{\rm Edd}$）的$\sim10\%$处达到峰值，对于质量较小的SMBH（例如，$M_{\rm BH} < 10^{8}M_{\odot}$）。这是因为对于较小的$L_{\rm AGN}$，CNDs的标度高度由SN驱动的吸积决定，而CNDs中的尘埃分子气体则被超过临界光度的活动星系核的辐射压吹走.另一方面，对于大规模SMBH（例如，$M_{\rm BH} > 10^{8}M_{\odot}$），$f_{\rm obs}$总是小于$0.2$，并且几乎与$L_{\rm AGN}$无关，因为CND的标度高度主要由CND的最大恒星形成效率（$C_{\rm *, max}$）控制。通过与活动星系核的中红外观测结果的比较，SN+辐射反馈模型与$C_{\rm *, max} = 10^{-7}\, {\rm yr}^{-1}$模型较好地再现了$M_\mathrm{BH} = 10^8 M_\odot$的观测结果。我们还发现，强烈的星暴或CND内无尘吸收体的存在是必要的，以解释X射线观测。
英文摘要：
We study the obscuring structure of circumnuclear disks (CNDs) by considering supernova (SN) feedbacks from nuclear starburst and the effect of anisotropic radiative pressure from AGNs. We suppose that the mass accretion onto a central supermassive black hole (SMBH) is triggered by SN-driven turbulence within CNDs, and we explore how the structures of CNDs depend on the BH mass ($M_{\rm BH}$) and AGN luminosity ($L_{\rm AGN}$). We find that the obscuring fraction ($f_{\rm obs}$) peaks at $\sim10\%$ of the Eddington luminosity ($L_{\rm Edd}$), and its maximal value is $f_\mathrm{obs} \sim 0.6$ for less massive SMBHs (e.g., $M_{\rm BH} < 10^{8}M_{\odot}$). This is because the scale height of CNDs is determined by the SN-driven accretion for a smaller $L_{\rm AGN}$, while the dusty molecular gas in CNDs is blown away by the radiation pressure from AGNs beyond the critical luminosity. On the other hand, for massive SMBHs (e.g., $M_{\rm BH} > 10^{8}M_{\odot}$), $f_{\rm obs}$ is always smaller than $0.2$, and it is almost independent of $L_{\rm AGN}$ because the scale height of CNDs is mainly controlled by the maximal star-formation efficiency ($C_{\rm *, max}$) in CNDs. By comparison with the obscuring fractions suggested from the mid-infrared observations of nearby AGNs, the SN plus radiative feedback model with $C_{\rm *, max} = 10^{-7}\, {\rm yr}^{-1}$ well reproduces the observations for $M_\mathrm{BH} = 10^8 M_\odot$. We also find that the intense starburst or the existence of dust-free absorbers inside CNDs are necessary, to explain X-ray observations.
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。
