Using data from the MIRIS Pa{ \alpha} Galactic Plane Survey (MIPAPS), we present a Pa{ \alpha} 1.87 um line image of the entire Galactic plane within the latitude range of -3{ \deg} < b < +3{ \deg}, revealing numerous Pa{ \alpha} features. Based on the MIPAPS Pa{ \alpha} image and the WISE H II region catalog, we compile a catalog of 1489 Pa{ \alpha} emission-line sources in the Galactic plane within 90{ \deg} < l < 330{ \deg}. By comparing our Pa{ \alpha} images with H{ \alpha} images constructed from the IPHAS and VPHAS+ survey data, we demonstrate the advantages of Pa{ \alpha} line observations. We identify 902 Pa{ \alpha} sources associated with H II regions, and newly confirm 619 H II region candidates as definitive H II regions through Pa{ \alpha} or H{ \alpha} detections. We also identify 261 extended and 326 point-like Pa{ \alpha} sources not included in the WISE catalog, most of which have H{ \alpha} counterparts in the IPHAS or VPHAS+ images. A search of the SIMBAD database indicates that these sources originate from diverse object types. By measuring Pa{ \alpha} and H{ \alpha} fluxes, we estimate the E(B-V) color excesses derived from extended emissions for 138 Pa{ \alpha} sources, showing good agreement with values obtained from spectrophotometry of ionizing stars in previous studies. Futhermore, we calculate total Lyman continuum luminosities for 42 Pa{ \alpha} 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 Pa{ \alpha} line observations and the benefits of combining multiple hydrogen recombination lines in exploring ionized regions.
Categories: astro-ph.GA astro-ph.SR