2018MNRAS.476.3744L -
Mon. Not. R. Astron. Soc., 476, 3744-3780 (2018/May-3)
The H IX galaxy survey - II. H I kinematics of H I eXtreme galaxies.
LUTZ K.A., KILBORN V.A., KORIBALSKI B.S., CATINELLA B., JOZSA G.I.G., WONG O.I., STEVENS A.R.H., OBRESCHKOW D. and DENES H.
Abstract (from CDS):
By analysing a sample of galaxies selected from the H I Parkes All Sky Survey (HIPASS) to contain more than 2.5 times their expected H I content based on their optical properties, we investigate what drives these H I eXtreme (H IX) galaxies to be so H I-rich. We model the H I kinematics with the Tilted Ring Fitting Code TiRiFiC and compare the observed H IX galaxies to a control sample of galaxies from HIPASS as well as simulated galaxies built with the semi-analytic model DARK SAGE. We find that (1) H I discs in H IX galaxies are more likely to be warped and more likely to host H I arms and tails than in the control galaxies, (2) the average H I and average stellar column density of H IX galaxies is comparable to the control sample, (3) H IX galaxies have higher H I and baryonic specific angular momenta than control galaxies, (4) most H IX galaxies live in higher spin haloes than most control galaxies. These results suggest that H IX galaxies are H I-rich because they can support more H I against gravitational instability due to their high specific angular momentum. The majority of the H IX galaxies inherits their high specific angular momentum from their halo. The H I content of H IX galaxies might be further increased by gas-rich minor mergers. This paper is based on data obtained with the Australia Telescope Compact Array through the large program C 2705.
Abstract Copyright:
© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society
Journal keyword(s):
galaxies: evolution - galaxies: formation - galaxies: ISM - galaxies: kinematics and dynamics
VizieR on-line data:
<Available at CDS (J/MNRAS/476/3744): hix-2.dat list.dat fits/*>
Errata:
erratum vol. 484, p.832 (2019)
Simbad objects:
45
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