Аннотация
We present new MUSE observations of a galaxy group probed by a background
quasar. The quasar sightline passes between multiple $z=0.28$ galaxies, whilst
showing at the same redshift low ionised metal line species, including Ca II,
Mg I, Mg II and Fe II. Based on the galaxy redshifts measured from the MUSE
data, we estimate the galaxies to be part of a small galaxy group with a halo
mass of $\approx6\times10^12$ M$_ødot$. We use the MUSE data to reveal the
two dimensional dynamical properties of the gas and stars in the group
galaxies, and relate these to the absorber kinematics. With these data we
consider four scenarios for the nature of the gas probed by the sightline
absorbers: a co-rotating gas halo associated with a single galaxy within the
group; outflowing material from a single group member powered by recent
star-formation; and cool dense gas embedded within the intra-group medium. We
find that the dynamics, alongside the galaxy impact parameters and
star-formation rates, favour the latter, in which the cool gas belongs to the
intra-group medium and is likely pressure confined within a warmer gas halo.
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