TY - JOUR

T1 - The distribution and properties of DLAs at z

AU - Garratt-Smithson, Lilian

AU - Power, Chris

AU - Lagos, Claudia del P.

AU - Stevens, Adam R. H.

AU - Allison, James R.

AU - Sadler, Elaine M.

PY - 2021/3/1

Y1 - 2021/3/1

N2 - Determining the spatial distribution and intrinsic physical properties of neutral hydrogen on cosmological scales is one of the key goals of next-generation radio surveys. We use the EAGLE galaxy formation simulations to assess the properties of damped Lyman a absorbers (DLAs) that are associated with galaxies and their underlying dark matter haloes between 0 = 10(10)M(circle dot); and the covering fraction of DLAs in the circumgalactic medium (CGM) is enhanced relative to that of the interstellar medium (ISM) with increasing halo mass. Moreover, we find that the mean density of the HI in galaxies increases with increasing stellar mass, while the DLAs in high- and low-halo mass systems have higher column densities than those in galaxies with intermediate halo masses (similar to 10(12) M-circle dot at z = 0). These high-impact CGM DLAs in high-stellar mass systems tend to be metal poor, likely tracing smooth accretion. Overall, our results point to the CGM playing an important role in DLA studies at high redshift (z >= 1). However, their properties are impacted both by numerical resolution and the detailed feedback prescriptions employed in cosmological simulations, particularly that of active galactic nuclei.

AB - Determining the spatial distribution and intrinsic physical properties of neutral hydrogen on cosmological scales is one of the key goals of next-generation radio surveys. We use the EAGLE galaxy formation simulations to assess the properties of damped Lyman a absorbers (DLAs) that are associated with galaxies and their underlying dark matter haloes between 0 = 10(10)M(circle dot); and the covering fraction of DLAs in the circumgalactic medium (CGM) is enhanced relative to that of the interstellar medium (ISM) with increasing halo mass. Moreover, we find that the mean density of the HI in galaxies increases with increasing stellar mass, while the DLAs in high- and low-halo mass systems have higher column densities than those in galaxies with intermediate halo masses (similar to 10(12) M-circle dot at z = 0). These high-impact CGM DLAs in high-stellar mass systems tend to be metal poor, likely tracing smooth accretion. Overall, our results point to the CGM playing an important role in DLA studies at high redshift (z >= 1). However, their properties are impacted both by numerical resolution and the detailed feedback prescriptions employed in cosmological simulations, particularly that of active galactic nuclei.

KW - galaxies: evolution

KW - galaxies: ISM

KW - quasars: absorption lines

KW - LYMAN-ALPHA SYSTEMS

KW - INTEGRAL FIELD SPECTROSCOPY

KW - STAR-FORMATION RATES

KW - DIGITAL SKY SURVEY

KW - H I ABSORBERS

KW - DAMPED LYMAN

KW - NEUTRAL HYDROGEN

KW - GALAXY FORMATION

KW - ATOMIC-HYDROGEN

KW - COSMOLOGICAL SIMULATIONS

U2 - 10.1093/mnras/staa3870

DO - 10.1093/mnras/staa3870

M3 - Journal article

VL - 501

SP - 4396

EP - 4419

JO - Royal Astronomical Society. Monthly Notices

JF - Royal Astronomical Society. Monthly Notices

SN - 0035-8711

IS - 3

ER -