Diagnostic Signatures of Radiative Feedback from Massive Stars

来自大质量恒星的辐射反馈对星系和宇宙的演化是非常重要的，它还提供了对本地和遥远宇宙条件的基本发射线诊断。我们目前对辐射反馈的有限理解极大地阻碍了对当今局部过程以及星系形成和早期宇宙的研究。洛厄尔天文台的Sally Oey博士将对辐射反馈过程进行全面调查，范围从具体的星云电离条件到星系和星系间介质中的大规模全球电离过程。目标是：1）具体了解电离光谱类型和化学丰度如何影响星云发射，并校准相应的星云谱线诊断; 2）通过研究扩散电离气体的大尺度性质，HII区域人口，以及电离光子从星系逃逸的影响，了解星系中的全球辐射反馈过程。***

AST 0204853OeyRadiative feedback from massive stars is energetically fundamental to galaxy and cosmic evolution, and it also provides essential emission-line diagnostics of conditions both locally and in the distant universe. Our current limited understanding of radiative feedback greatly hampers investigations of present-day local processes as well as of galaxy formation and the early universe. Dr. Sally Oey, at Lowell Observatory, will carry out a comprehensive investigation of radiative feedback processesranging from specific nebular ionization conditions to large-scale, global ionization processes in galaxies and the intergalactic medium. The goals are: 1) To understand specifically how ionizing spectral types and chemical abundances affect nebular emission, and to calibrate corresponding nebular line diagnostics; and 2) to understand global radiative feedback processes in galaxies by investigating large-scale properties of diffuse ionized gas, HII region populations, and implications for the escape of ionizing photons from galaxies. ***