题目：Probing cosmic reionization with Ly-alpha observations from JWST

报告人： 陈祖诒 博士（Steward Observatory,University of Arizona）

摘 要：The JWST are ushering in a new era of observing galaxies in the reionization era,providing us new insights into this last major phase transition of the Universe. The Ly-alpha emission from young star forming galaxies,which is sensitive to the presence of neutral HI along the line of sight,has been used as an important probe of this process. JWST/NIRSpec offers spectroscopic capabilities that allow for efficient detections of z>~6 Ly-alpha emission lines in the absence of atmospheric OH lines down to very faint continuum magnitudes (~ 29 mag). In this talk,I will present our recent work using NIRSpec observations to directly constrain the reionization timeline by measuring the Ly-alpha escape fractions. I will show the detection of extremely strong Ly-alpha in z>7 galaxies,and its implications for the presence of large ionized bubbles when the universe is significantly neutral. Lastly,I will discuss how Ly-alpha visibility in early galaxies may depend on their local environments and what we learned for future Ly-alpha observations.

时间：2024年6月17日周一10:00

地点：紫台5号楼516会议室

欢迎大家参加！