Astrophysics Seminar
Probing the intergalactic medium during the Universe’s First Billion Years
Speaker: Raghunath Ghara (Department of Natural and Life Sciences, The Open University of Israel, Israel)
The formation of the first luminous sources initiated the transition of the cold and neutral intergalactic medium (IGM) into a hot and ionized state. The redshifted 21-cm signal from the IGM neutral hydrogen is the most promising probe of the Universe’s First Billion Years when this transition took place. Recent results from radio observations such as LOFAR, MWA, HERA, SARAS and EDGES have started constraining the reionization scenario. Besides constraining the properties of the early astrophysical sources and cosmology, these radio observations are also used to study the properties of the IGM. In this seminar, I will be talking about the states of the IGM during the epoch of hydrogen reionization, the 21-cm observations and the constraints on the states of the IGM as obtained from these observations.