In this pilot study, we investigate the known PN population in M 33, a nearby spiral galaxy, at a distance of ≈ 840 kpc, using data from the DR3 of the Javalambre-Photometric Local Universe Survey (J-PLUS), a 12-band photometric dataset extensively used to identify H α line emitters. From the 143 known PNe of M 33, the photometry of only 13 is present in the J-PLUS catalog, as available on the J-PLUS portal. With the aim of recovering a larger fraction of the M 33 PN population, the software SExtractor is adopted to extract the sources in the J-PLUS images and obtain the photometric data for the PNe known in the literature, performing either PSF or aperture photometry. With this procedure the photometry of 98 PNe was obtained using H α image as detection image, including the 13 already present in the J-PLUS catalog. Using diagnostic color-color diagrams based on criteria developed for Milky Way halo PNe, we identified 16 sources with PN-like colors. Cross-match with existing catalogs revealed that most of these candidates are H II regions, though one source remains unidentified. Additionally, analyzing their full width at half maximum, most of them would not be PN candidates. This highlights the method’s ability to select emission-line objects but also underscores the challenge of distinguishing PNe from contaminants using photometry alone. The J-PLUS colors of the full sample of 98 known PNe were analyzed, together with literature information on their radial velocities, resulting in the identification of one possible halo PN. This is the first paper which aims at detecting extragalactic PNe in multi-band surveys such as J-PLUS, the Southern Local Universe Survey (S-PLUS) and the Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS), paving the way for similar studies in these surveys for other nearby galaxies, which lack catalogs of known PNe.
Liberato et al. (Fri,) studied this question.