Dataset Information

Observations of a Magellanic Corona.

ABSTRACT: The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are the closest massive satellite galaxies of the Milky Way. They are probably on their first passage on an infalling orbit towards our Galaxy¹ and trace the continuing dynamics of the Local Group². Recent measurements of a high mass for the LMC (M_halo ≈ 10^11.1-11.4 M_⊙)^3-6 imply that the LMC should host a Magellanic Corona: a collisionally ionized, warm-hot gaseous halo at the virial temperature (10^5.3-5.5 K) initially extending out to the virial radius (100-130 kiloparsecs (kpc)). Such a corona would have shaped the formation of the Magellanic Stream⁷, a tidal gas structure extending over 200° across the sky^2,8,9 that is bringing in metal-poor gas to the Milky Way¹⁰. Here we show evidence for this Magellanic Corona with a potential direct detection in highly ionized oxygen (O⁺⁵) and indirectly by means of triply ionized carbon and silicon, seen in ultraviolet (UV) absorption towards background quasars. We find that the Magellanic Corona is part of a pervasive multiphase Magellanic circumgalactic medium (CGM) seen in many ionization states with a declining projected radial profile out to at least 35 kpc from the LMC and a total ionized CGM mass of log₁₀(M_H II,CGM/M_⊙) ≈ 9.1 ± 0.2. The evidence for the Magellanic Corona is a crucial step forward in characterizing the Magellanic group and its nested evolution with the Local Group.

SUBMITTER: Krishnarao D

PROVIDER: S-EPMC9519455 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Observations of a Magellanic Corona.

Krishnarao Dhanesh D Fox Andrew J AJ D'Onghia Elena E Wakker Bart P BP Cashman Frances H FH Howk J Christopher JC Lucchini Scott S French David M DM Lehner Nicolas N

Nature 20220928 7929

The Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC) are the closest massive satellite galaxies of the Milky Way. They are probably on their first passage on an infalling orbit towards our Galaxy1 and trace the continuing dynamics of the Local Group2. Recent measurements of a high mass for the LMC (Mhalo ≈ 1011.1-11.4 M⊙)3-6 imply that the LMC should host a Magellanic Corona: a collisionally ionized, warm-hot gase ...[more]

PMID: 36171382

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Dataset Information

Observations of a Magellanic Corona.

Publications

Observations of a Magellanic Corona.

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