133322 - The Southern H II Region Discovery Survey. I - the Bright Catalog.pdf (2.78 MB)
The Southern H Ⅱ Region Discovery Survey. I: the Bright Catalog
journal contribution
posted on 2023-05-20, 04:25 authored by Wenger, TV, John DickeyJohn Dickey, Jordan, CH, Balser, DS, Armentrout, WP, Anderson, LD, Bania, TM, Dawson, JR, McClure-Griffiths, NM, Shea, JThe census of Galactic H Ⅱ regions is vastly incomplete in the southern sky. We use the Australia Telescope Compact Array to observe 4-10 radio continuum and hydrogen radio recombination line (RRL) emission from candidate H Ⅱ regions in the Galactic zone 250° < 𝓁 < 344°,|b|4°. In this first data release, we target the brightest H Ⅱ region candidates and observe 282 fields in the direction of at least one previously known or candidate H Ⅱ region. We detect radio continuum emission and RRL emission in 275 (97.5%) and 258 (91.5%) of these fields, respectively. We catalog the ∼7 GHz radio continuum peak flux densities and positions of 80 previously known and 298 candidate H Ⅱ regions. After averaging ∼18 RRL transitions, we detect 77 RRL velocity components toward 76 previously known H Ⅱ regions and 267 RRL velocity components toward 256 H Ⅱ region candidates. The discovery of RRL emission from these nebulae increases the number of known Galactic H Ⅱ regions in the surveyed zone by 82% to 568 nebulae. In the fourth quadrant, we discover 50 RRLs with positive velocities, placing those sources outside the solar circle. Including the pilot survey, the Southern H Ⅱ Region Discovery Survey has now discovered 295 Galactic H Ⅱ regions. In the next data release, we expect to add ∼200 fainter and more distant nebulae.
History
Publication title
Astrophysical Journal, Supplement SeriesVolume
240Article number
24Number
24Pagination
1-19ISSN
0067-0049Department/School
School of Natural SciencesPublisher
Univ Chicago PressPlace of publication
1427 E 60Th St, Chicago, USA, Il, 60637-2954Rights statement
Copyright 2019 The American Astronomical SocietyRepository Status
- Open