Observations of a Magellanic Corona

Abstract

The Large and Small Magellanic Clouds (LMC/SMC) are the closest major satellite galaxies of the Milky Way. They are likely on their first passage on an infalling orbit towards our Galaxy (Besla et al. 2007) and trace the ongoing dynamics of the Local Group (D'Onghia & Fox 2016). Recent measurements of a high mass for the LMC (M_halo = 10^(11.1-11.4) solar masses; Penarrubia et al. 2016, Erkal et al. 2018, 2019, Kallivayalil et al. 2018) imply 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 kpc). Such a Corona would have shaped the formation of the Magellanic Stream (Lucchini et al. 2020), a tidal gas structure extending over 200 degrees across the sky (D'Onghia & Fox 2016, Besla et al. 2012, Nidever et al. 2010) that is bringing in metal poor gas to the Milky Way (Fox et al. 2014). No observational evidence for such an extended Corona has been published previously, with detections of highly ionized gas only reported in directions directly toward the LMC, where winds from the LMC disk may dominate (deBoer & Savage 1980, Wakker et al. 1998). Here we show evidence for this Magellanic Corona with a potential direct detection in highly ionized oxygen (O^+5), and indirectly via triply-ionized carbon and silicon, seen in ultraviolet absorption toward 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 log_10(M_HII;CGM/solar masses) = 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.

arXiv commentView published, open access version here: https://www.nature.com/articles/s41586-022-05090-5 Main Text: 7 Pages, 4 Figures Methods: 19 Pages, 7 Extended Data Figures, 3 Extended Data Tables

References in corpus (48)

• Astropy: A Community Python Package for Astronomy
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• HI4PI: A full-sky HI survey based on EBHIS and GASS
• Some Aspects of Measurement Error in Linear Regression of Astronomical Data
• Radiative transfer in a clumpy universe: IV. New synthesis models of the cosmic UV/X-ray background
• The Circumgalactic Medium
• A distance to the Large Magellanic Cloud that is precise to one per cent
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• Are the Magellanic Clouds on their First Passage about the Milky Way?
• Gaseous Galaxy Halos
• Time-Dependent Ionization in Radiatively Cooling Gas
• The Role of Dwarf Galaxy Interactions in Shaping the Magellanic System and Implications for Magellanic Irregulars
• The total mass of the Large Magellanic Cloud from its perturbation on the Orphan stream
• H3+ in Diffuse Interstellar Clouds: a Tracer for the Cosmic-Ray Ionization Rate
• The COS-Dwarfs Survey: The Carbon Reservoir Around sub-L* Galaxies
• A timing constraint on the (total) mass of the Large Magellanic Cloud
• The Escape of Ionizing Photons from the Galaxy
• Small Dwarf Galaxies Within Larger Dwarfs: Why Some Are Luminous While Most Go Dark
• Multi-phase High-Velocity Clouds toward HE 0226-4110 and PG 0953+414
• The Magellanic Stream: Circumnavigating the Galaxy
• The 200 Degree-Long Magellanic Stream System
• The COS/UVES Absorption Survey of the Magellanic Stream. III: Ionization, Total Mass, and Inflow Rate onto the Milky Way
• A Reservoir of Ionized Gas in the Galactic Halo to Sustain Star Formation in the Milky Way
• The Missing Satellites of the Magellanic Clouds? Gaia Proper Motions of the Recently Discovered Ultra-Faint Galaxies
• The Source of Ionization along the Magellanic Stream
• A FUSE survey of high-latitude Galactic molecular hydrogen
• The COS/UVES Absorption Survey of the Magellanic Stream: II. Evidence for a complex enrichment history of the Stream from the Fairall 9 sightline
• Stellar streams around the Magellanic Clouds
• The COS/UVES Absorption Survey of the Magellanic Stream: I. One-Tenth Solar Abundances along the Body of the Stream
• Project AMIGA: The Circumgalactic Medium of Andromeda
• Modelling the Tucana III stream - a close passage with the LMC
• The large-scale ionization cones in the Galaxy
• The Magellanic Corona and the formation of the Magellanic Stream
• Toward a Complete Understanding of the Magellanic Stream Formation
• C II Radiative Cooling of the Diffuse Gas in the Milky Way
• Metallicity and Physical Conditions in the Magellanic Bridge
• Accretion of the Magellanic system onto the Galaxy
• Atomic Data Revisions for Transitions Relevant to Observations of Interstellar, Circumgalactic, and Intergalactic Matter
• Time-Dependent Cooling in Photoionized Plasma
• A New FUSE Survey of Interstellar HD
• Local ultra faint dwarves as a product of Galactic processing during a Magellanic group infall
• Project AMIGA: A Minimal Covering Factor for Optically Thick Circumgalactic Gas Around the Andromeda Galaxy
• Kinematics of the Magellanic Stream and Implications for its Ionization
• Si iv Column Densities Predicted from Non-Equilibrium Ionization Simulations of Turbulent Mixing Layers and High-Velocity Clouds
• VoigtFit: A Python package for Voigt profile fitting
• High-velocity gas towards the LMC resides in the Milky Way halo
• The HI Column Density Distribution of the Galactic Disk and Halo
• A Compact High Velocity Cloud near the Magellanic Stream: Metallicity and Small-Scale Structure

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