Nous caractérisons le milieu circumgalactique chaud (CGM) of a dwarf galaxy pair
with properties similar to the Magellanic Clouds in the \textsc{Hestia}
simulations cosmologiques. Le système est constitué d'un nain massif ($M_{\bonjour}
\sim 10 ^{11.5} M_{\odot}$) et un compagnon de masse inférieure ($M_{\bonjour} \sim
10^{10} M_{\odot}$), dynamically evolving in isolation before infall into a
Milky Way-mass halo. The massive dwarf hosts a warm coronal gas envelope with a
temperature of $T \sim 3 \times 10^5$ K, consistent with expectations for
virialized CGM in dwarf halos. Tidal interactions produce a neutral gas stream
that extends over $\sim 150$ kpc, with an \ion{H}{1} mass of $M_{\rm HI} \sim
10^8 M_{\odot}$, similar to the Magellanic Stream. Furthermore, in the
\textsc{Hestia} simulation suite, we find that coronal gas is ubiquitous in all
halos with $M_{\bonjour} > 10^{11} M_{\odot}$, implying that massive dwarfs
generically develop extended gaseous envelopes prior to accretion. This result
has significant implications for the survival of neutral tidal structures, et
suggests that current and future high-ion UV absorption-line observations are
indicative of warm coronae surrounding LMC-mass dwarfs, independent of their
environment.

Cet article explore les excursions dans le temps et leurs implications.

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