低红移尘埃活动星系的演化范式
An Evolutionary Paradigm for Dusty Active Galaxies at Low Redshift
摘要：
我们将贝叶斯推理和图论方法应用于102个中红外光谱的数据集，以及从光学到毫米的档案数据，以构建z<0.4的红外发光星系（ULIRGs）的演化范式。我们建议ULIRG的生命周期包括三个阶段。第一阶段从最初的相遇持续到近似合并。它的特点是均匀的中红外光谱形状，红外辐射主要来自恒星形成，在某些情况下有活动星系核的贡献。在这一阶段结束时，ULIRG进入两条演化路径之一，这取决于合并的动力学、可用的气体量和祖先中黑洞的质量。在一个分支上，星暴和活动星系核对总红外光度的贡献分别减小和增大。红外光谱的形状是不均匀的，可能是由于反馈活动星系核驱动的风。有些物体在最后会经历一个短暂的类星体阶段。在另一个分支中，星暴相对于活动星系核的衰减不太明显，很少或没有天体经历类星体阶段。我们发现，11.2微米的PAH功能是一个非常好的诊断进化阶段，并确定六个ULIRGs，可能是原型的关键阶段，在这个生命周期。
英文摘要：
We apply methods from Bayesian inferencing and graph theory to a dataset of 102 mid-infrared spectra, and archival data from the optical to the millimeter, to construct an evolutionary paradigm for z<0.4 infrared-luminous galaxies (ULIRGs). We propose that the ULIRG lifecycle consists of three phases. The first phase lasts from the initial encounter until approximately coalescence. It is characterized by homogeneous mid-IR spectral shapes, and IR emission mainly from star formation, with a contribution from an AGN in some cases. At the end of this phase, a ULIRG enters one of two evolutionary paths depending on the dynamics of the merger, the available quantities of gas, and the masses of the black holes in the progenitors. On one branch, the contributions from the starburst and the AGN to the total IR luminosity decline and increase respectively. The IR spectral shapes are heterogeneous, likely due to feedback from AGN-driven winds. Some objects go through a brief QSO phase at the end. On the other branch, the decline of the starburst relative to the AGN is less pronounced, and few or no objects go through a QSO phase. We show that the 11.2 micron PAH feature is a remarkably good diagnostic of evolutionary phase, and identify six ULIRGs that may be archetypes of key stages in this lifecycle.
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。
