2023/09/04 by D N Kosenko, Kosenko, D. N., S. A. Balashev +1
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Astrophysics of Galaxies (astro-ph.GA) #FOS: Physical sciences #Stellar, planetary, and galactic studies
paper · pdf · doi:10.48550/arxiv.2309.01600
openalex publication_date 2023/09/04 · openalex created_date 2023/09/09 · openalex updated_date 2026/07/28
HD molecule is one the most abundant molecule in the Universe and due to its sensibility to the conditions in the medium, it can be used to constrain physical parameters in the medium where HD resides. Lately we have shown that HD abundance can be enhanced in the low metallicity medium. Large and Small Magellanic Clouds give us an opportunity to study low metallicity galaxies in details towards different sightlines due to their proximity to our Galaxy. We revisited FUSE space telescope archival spectra towards bright stars in Magellanic Clouds to search for HD molecules, associated with the medium of these galaxies. We reanalysed H2 absorption lines and constrained HD column density at the positions of H2 components. We detected HD towards 24 sightlines (including 19 new detections). We try to measure cosmic ray ionization rate for several systems using measured N(\rm HD)/N(\rm H2), and in most cases get loose constraints due to insufficient quality of the FUSE spectra.