HII regions at 76.2MHz synchrotron emissivities

We derive the synchrotron distribution in the Milky Way disc from HII region absorption observations over -40{deg}<l<40{deg} at six frequencies of 76.2, 83.8, 91.5, 99.2, 106.9, and 114.6MHz with the GaLactic and Extragalactic All-sky Murchison Widefield array survey (GLEAM). We develop a new method of emissivity calculation by taking advantage of the Haslam et al. (1981A&A...100..209H) map and known spectral indices, which enable us to simultaneously derive the emissivity and the optical depth of HII regions at each frequency. We show our derived synchrotron emissivities based on 152 absorption features of HII regions using both the method previously adopted in the literature and our improved method. We derive the synchrotron emissivity from HII regions to the Galactic edge along the line of sight and, for the first time, derive the emissivity from HII regions to the Sun. These results provide direct information on the distribution of the Galactic magnetic field and cosmic ray electrons for future modelling.

Identifier
Source https://dc.g-vo.org/rr/q/lp/custom/CDS.VizieR/J/MNRAS/479/4041
Related Identifier https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/479/4041
Related Identifier http://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/479/4041
Metadata Access http://dc.g-vo.org/rr/q/pmh/pubreg.xml?verb=GetRecord&metadataPrefix=oai_b2find&identifier=ivo://CDS.VizieR/J/MNRAS/479/4041
Provenance
Creator Su H.; Macquart J.P.; Hurley-Walker N.; McClure-Griffiths N.M.,Jackson C.A.; Tingay S.J.; Tian W.W.; Gaensler B.M.; McKinley B.,Kapinska A.D.; Hindson L.; Hancock P.; Wayth R.B.; Staveley-Smith L.,Morgan J.; Johnston-Hollitt M.; Lenc E.; Bell M.E.; Callingham J.R.,Dwarkanath K.S.; For B.-Q.; Offringa A.R.; Procopio P.; Wu C.; Zheng Q.
Publisher CDS
Publication Year 2022
Rights https://cds.unistra.fr/vizier-org/licences_vizier.html
OpenAccess true
Contact CDS support team <cds-question(at)unistra.fr>
Representation
Resource Type Dataset; AstroObjects
Discipline Astrophysics and Astronomy; Cosmology; Interstellar medium; Natural Sciences; Physics