RESEARCH / 01
Galaxies & the cosmic web
Connecting galaxies to the gas between them
My doctoral research centers on the relationship between galaxies and neutral hydrogen in the intergalactic medium (IGM) at redshift z ≈ 2. This connects the environments of individual galaxies to the much larger structures of the cosmic web.
Two complementary views of the same environment
Narrowband images from Subaru’s Hyper Suprime-Cam identify galaxies through their Lyα emission. Spectra of more distant quasars reveal intervening hydrogen through Lyα absorption. Comparing these observations lets us investigate the relationship between galaxy density and absorption by surrounding gas.
From a published sample to a broader program
In a four-field study published in 2021, we found that Lyα-emitting galaxies preferentially cluster in regions with stronger hydrogen absorption on scales extending to several physical megaparsecs. This study is one published part of my broader doctoral-thesis program on the galaxy–IGM connection.
Where quasars change the picture
The Cosmic Himalayas field shows that peaks in the distributions of quasars, galaxies, and hydrogen absorption need not coincide. Comparing such environments helps us investigate how matter density and radiation together shape the observable gas around galaxies.
References
Cosmic Himalayas: The Highest Quasar Density Peak Identified in a 10,000 deg² Sky with Spatial Discrepancies between Galaxies, Quasars, and IGM H I
ApJ, 986, 60
Statistical Correlation between the Distribution of Lyα Emitters and Intergalactic Medium H I at z ∼ 2.2 Mapped by the Subaru/Hyper Suprime-Cam
ApJ, 907, 3