题目：Modelling the Cosmic Dawn
报告人：秦宇翔，博士毕业于墨尔本大学，现于意大利比萨高等师范学校(Scuola Normale Superiore, Italy)从事博士后研究工作，主要从事宇宙再电离，早期星系形成，高红移黑洞等理论研究。
摘要：The measurement of the cosmic 21-cm signal with the SKA will transform our understanding of the epochs of reionization and cosmic dawn. The properties of the first stars and galaxies are encoded in the patterns of the signal. Interpreting these patterns requires accurate and efficient models. I will present an update of the 21cmFAST semi-numerical simulation, which separately accounts for star-formation inside the very first galaxies. This unseen and transient population of galaxies obtain their gas through molecular cooling from the intergalactic medium, and could have markedly different properties from the more massive galaxies observed with Hubble and eventually JWST. I demonstrate that if the recently-reported EDGES signal at z~17 is genuinely cosmological, these molecularly-cooled “mini-halo” galaxies must have played a dominant role during Cosmic Dawn.