发布日期：2023-12-25
点击次数：
标题：Constraining the Cosmic Partition of IGM and CGM Baryons with FRB Foreground Mapping
时间：Monday, December 25, 2023, 11:00am
主讲人：Khee-Gan Lee 李启根 (Kavli-IPMU)
地点：S727
The frequency shifts measured in extragalactic Fast radio bursts (FRB)s probe the total column of ionized gas in the foreground, including large contributions from the CGM and IGM. By combining this information with both deep and wide spectroscopic observations of foreground galaxies, the information content is enhanced. The wide-field data (∼10s of Mpc scales) allows us to reconstruct the underlying cosmic web that underlie the IGM gas, while the deep data within <1Mpc allows a census of the potential CGM contributions. With this kind of data on an ensemble of FRB fields, we will be able to constrain the relative partition of ionized baryons in the IGM and CGM, as well as the typical extents of the latter. I will show that these quantities reflect the imprint of galaxy and AGN feedback in expelling gas from galaxy halos, as seen in cosmological hydrodynamical simulations. I will describe FLIMFLAM, a follow-up spectroscopic program that is aimed at observing ∼20 localized FRB fields, and provide forecasts for future surveys.
