TY - JOUR
T1 - Atomic hydrogen in IllustrisTNG galaxies
T2 - the impact of environment parallelled with local 21-cm surveys
AU - Stevens, Adam R. H.
AU - Diemer, Benedikt
AU - Lagos, Claudia del P.
AU - Nelson, Dylan
AU - Pillepich, Annalisa
AU - Brown, Toby
AU - Catinella, Barbara
AU - Hernquist, Lars
AU - Weinberger, Rainer
AU - Vogelsberger, Mark
AU - Marinacci, Federico
PY - 2019/3
Y1 - 2019/3
N2 - We investigate the influence of environment on the cold-gas properties of galaxies at z = 0 within the TNG100 cosmological, magnetohydrodynamic simulation, part of the IllustrisTNG suite. We extend previous post-processing methods for breaking gas cells into their atomic and molecular phases, and build detailed mocks to comprehensively compare to the latest surveys of atomic hydrogen (H I) in nearby galaxies, namely ALFALFA and xGASS. We use TNG100 to explore the H I content, star formation activity, and angular momentum of satellite galaxies, each as a function of environment, and find that satellites are typically a factor of greater than or similar to 3 poorer in H I than centrals of the same stellar mass, with the exact offset depending sensitively on parent halo mass. Due to the large physical scales on which H I measurements are made (similar to 45-245 kpc), contributions from gas not bound to the galaxy of interest but in the same line of sight crucially lead to larger H I mass measurements in the mocks in many cases, ultimately aligning with observations. This effect is mass-dependent and naturally greater for satellites than centrals, as satellites are never isolated by definition. We also show that H I stripping in TNG100 satellites is closely accompanied by quenching, in tension with observational data that instead favour that H I is preferentially stripped before star formation is reduced.
AB - We investigate the influence of environment on the cold-gas properties of galaxies at z = 0 within the TNG100 cosmological, magnetohydrodynamic simulation, part of the IllustrisTNG suite. We extend previous post-processing methods for breaking gas cells into their atomic and molecular phases, and build detailed mocks to comprehensively compare to the latest surveys of atomic hydrogen (H I) in nearby galaxies, namely ALFALFA and xGASS. We use TNG100 to explore the H I content, star formation activity, and angular momentum of satellite galaxies, each as a function of environment, and find that satellites are typically a factor of greater than or similar to 3 poorer in H I than centrals of the same stellar mass, with the exact offset depending sensitively on parent halo mass. Due to the large physical scales on which H I measurements are made (similar to 45-245 kpc), contributions from gas not bound to the galaxy of interest but in the same line of sight crucially lead to larger H I mass measurements in the mocks in many cases, ultimately aligning with observations. This effect is mass-dependent and naturally greater for satellites than centrals, as satellites are never isolated by definition. We also show that H I stripping in TNG100 satellites is closely accompanied by quenching, in tension with observational data that instead favour that H I is preferentially stripped before star formation is reduced.
KW - galaxies: evolution
KW - galaxies: haloes
KW - galaxies: interactions
KW - galaxies: ISM
KW - galaxies: star formation
KW - TO-MOLECULAR TRANSITION
KW - STAR-FORMATION RATES
KW - ARECIBO SDSS SURVEY
KW - H I
KW - RAM-PRESSURE
KW - COSMOLOGICAL SIMULATIONS
KW - STELLAR MASS
KW - GAS CONTENT
KW - PHYSICAL-PROPERTIES
KW - SEMIANALYTIC MODEL
U2 - 10.1093/mnras/sty3451
DO - 10.1093/mnras/sty3451
M3 - Article
VL - 483
SP - 5334
EP - 5354
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
SN - 0035-8711
IS - 4
ER -