TY - JOUR
T1 - The HETDEX Survey
T2 - Probing Neutral Hydrogen in the Circumgalactic Medium of ∼88,000 Lyα Emitters
AU - Khanlari, Mahan Mirza
AU - Gebhardt, Karl
AU - Weiss, Laurel H.
AU - Davis, Dustin
AU - Cooper, Erin Mentuch
AU - Qezlou, Mahdi
AU - Niemeyer, Maja Lujan
AU - Ciardullo, Robin
AU - Schneider, Donald P.
AU - Mukae, Shiro
AU - Liu, Chenxu
AU - Farrow, Daniel
AU - Hill, Gary J.
AU - Zeimann, Gregory R.
AU - Kollatschny, Wolfram
N1 - Publisher Copyright:
© 2025. The Author(s). Published by the American Astronomical Society.
PY - 2025/8/20
Y1 - 2025/8/20
N2 - We explore the neutral hydrogen (H i) gas around 1.9 < z < 3.5 Lyman alpha emitters (LAEs) from the Hobby-Eberly Telescope Dark Energy Experiment using faint Lyα absorption. This absorption is the result of H i in the halo of the LAE scattering Lyα photons from the integrated light of background galaxies along the line of sight. We stack millions of spectra from regions around ∼88,000 LAEs, in order to focus on the physics of the gas at large radii. The extensive number of fiber spectra contributing to the stacks ensures a sufficient signal-to-noise ratio to detect the faint Lyα absorption, which would otherwise be buried within the noise. We detect absorption out to a projected ∼350 kpc around an average LAE at z ∼ 2.5. We use these results to create an empirical radial Wλ(Lyα) profile around LAEs. Comparison with numerical simulations reveals a profile similar to the empirical one within this region. Compared to previous studies, the profile is similar but modestly higher. We also outline a simple physical picture motivated by the observed trends in the data. We plan to quantify this radial profile as a function of redshift, local density, and Lyα luminosity, to explore the relationship between LAE environments and H i distribution.
AB - We explore the neutral hydrogen (H i) gas around 1.9 < z < 3.5 Lyman alpha emitters (LAEs) from the Hobby-Eberly Telescope Dark Energy Experiment using faint Lyα absorption. This absorption is the result of H i in the halo of the LAE scattering Lyα photons from the integrated light of background galaxies along the line of sight. We stack millions of spectra from regions around ∼88,000 LAEs, in order to focus on the physics of the gas at large radii. The extensive number of fiber spectra contributing to the stacks ensures a sufficient signal-to-noise ratio to detect the faint Lyα absorption, which would otherwise be buried within the noise. We detect absorption out to a projected ∼350 kpc around an average LAE at z ∼ 2.5. We use these results to create an empirical radial Wλ(Lyα) profile around LAEs. Comparison with numerical simulations reveals a profile similar to the empirical one within this region. Compared to previous studies, the profile is similar but modestly higher. We also outline a simple physical picture motivated by the observed trends in the data. We plan to quantify this radial profile as a function of redshift, local density, and Lyα luminosity, to explore the relationship between LAE environments and H i distribution.
UR - https://www.scopus.com/pages/publications/105013287625
UR - https://www.scopus.com/pages/publications/105013287625#tab=citedBy
U2 - 10.3847/1538-4357/adf10e
DO - 10.3847/1538-4357/adf10e
M3 - Article
AN - SCOPUS:105013287625
SN - 0004-637X
VL - 989
JO - Astrophysical Journal
JF - Astrophysical Journal
IS - 2
M1 - 169
ER -