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Download fileFirst detection of HCO+ absorption in the Magellanic System
journal contribution
posted on 2023-05-18, 12:15 authored by Murray, CE, Stanimirovic, S, McClure-Griffiths, NM, Putman, ME, Liszt, HS, Wong, T, Richter, P, Dawson, JR, John DickeyJohn Dickey, Lindner, RR, Babler, BL, Allison, JRWe present the first detection of HCO+ absorption in the Magellanic System. Using the ATCA, we observed nine extragalactic radio continuum sources behind the Magellanic System and detected HCO+ absorption toward one source located behind the leading edge of the Magellanic Bridge. The detection is located at an LSR velocity of v = 214.0 ± 0.4 km s-1, with an FWHM of Δv = 4.5 ± 1.0 km s-1, and an optical depth of τ(HCO+) = 0.10 ± 0.02. Although there is abundant neutral hydrogen (HI) surrounding the sight line in position–velocity space, at the exact location of the absorber the HI column density is low, <1020 cm-2, and there is little evidence for dust or CO emission from Planck observations. While the origin and survival of molecules in such a diffuse environment remain unclear, dynamical events such as HI flows and cloud collisions in this interacting system likely play an important role.
Funding
Australian Research Council
History
Publication title
The Astrophysical JournalVolume
808Article number
41Number
41Pagination
1-6ISSN
0004-637XDepartment/School
School of Natural SciencesPublisher
Univ Chicago PressPlace of publication
1427 E 60Th St, Chicago, USA, Il, 60637-2954Rights statement
Copyright 2015 The American Astronomical SocietyRepository Status
- Open