MIRIS Paα Galactic Plane Survey. II. The Catalog of Paα Emission-line Sources
Year: 2025
Type: article
Abstract: Using data from the MIRIS Paα Galactic Plane Survey (MIPAPS), we present a Paα 1.87 μm line image of the entire Galactic plane within the latitude range of −3° ≲ b ≲ +3°, revealing numerous Paα features. Based on the MIPAPS Paα image and the Wide-field Infrared Survey Explorer (WISE) H ii region catalog, we compile a catalog of 1489 Paα emission-line sources in the Galactic plane within 90° ≤ ℓ ≤ 330°. By comparing our Paα images with Hα images constructed from the IPHAS and VPHAS+ survey data, we demonstrate the advantages of Paα line observations. We identify 902 Paα sources associated with H ii regions, and newly confirm 619 H ii region candidates as definitive H ii regions through Paα or Hα detections. We also identify 261 extended and 326 pointlike Paα sources not included in the WISE catalog, most of which have Hα counterparts in the IPHAS or VPHAS+ images. A search of the SIMBAD database indicates that these sources originate from diverse object types. By measuring Paα and Hα fluxes, we estimate the E(B − V) color excesses derived from extended emissions for 138 Paα sources, showing good agreement with values obtained from spectrophotometry of ionizing stars in previous studies. Furthermore, we calculate total Lyman continuum luminosities for 42 Paα sources, providing constraints on the distances to H ii regions and the spectral types of their ionizing stars. These results highlight the scientific potential of Paα line observations and the benefits of combining multiple hydrogen recombination lines in exploring ionized regions.
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
OpenAlex ID: W4413028968