Catalog of Planetary Nebulae Detected by GALEX and Corollary Optical Surveys

Abstract

Planetary nebulae (PNs) consist of an ionized envelope surrounding a hot central star (CSPN) that emits mostly at ultraviolet (UV) wavelengths. UV observations, therefore, provide important information on both the CSPN and the nebula. We have matched the PNs in the Hong Kong/Australian Astronomical Observatory/Strasbourg Hα catalog with the Galaxy Evolution Explorer (GALEX) UV sky surveys, the Sloan Digital Sky Survey (SDSS) data release 16, and the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) PS1 second release. A total of 671 PNs were observed by GALEX with the far-UV (FUV; 1344 Å–1786 Å) and/or the near-UV (NUV; 1771 Å–2831 Å) detectors on (GUVPNcat); 83 were observed by SDSS (PNcatxSDSSDR16) and 1819 by Pan-STARRS (PNcatxPS1MDS). We merged a distilled version of these matched catalogs into GUVPNcatxSDSSDR16xPS1MDS, which contains a total of 375 PNs with both UV and optical photometry over a total spectral coverage of ∼1540 Å–9610 Å. We analyzed separately 170 PNs resolved in GALEX images and determined their UV radius by applying a flux profile analysis. The CSPN flux could be extracted separately from the PN emission for 8 and 50 objects with SDSS and Pan-STARRS counterparts, respectively. The multiband photometry was used to distinguish between compact and extended PNs and CSPNs (binary CSPNs) by color–color diagram analysis. We found that compact PN candidates could be identified by using the r − i < − 0.4 and −1 < FUV−NUV < 1 colors, whereas binary CSPN candidates in given T eff ranges (all with color r−i > −0.4) can be identified in the color region (FUV−NUV) ≤ 6(r−i)+1.3, −0.8 < FUV−NUV < 0.4, and r−i < 0.75.

Detection of Faint Sources by the UltraViolet Imaging Telescope Onboard AstroSat Using Poisson Distribution of Background

“…It is an important tracer of star formation and the effect of intrinsic dust extinction in galaxies (e.g., Bianchi et al 1999;Chandar et al 1999;Kong et al 2004;Salim et al 2007;Kennicutt & Evans 2012;Calzetti 2013, and references therein). It also plays a pivotal role in exploring our galaxy's stellar population, including massive stars and objects like planetary nebulae, cataclysmic variables, blue straggler stars, and white dwarfs (e.g., Sion 1999;Bianchi et al 2011;Subramaniam et al 2020;Rao et al 2021;Gómez-Muñoz et al 2023). The study of active galaxies in UV provided information in characterizing the "big blue bump" (Sanders et al 1989), likely to be originating from accretion disks in active galactic nuclei (e.g., Shields 1978;Ward et al 1987), and also emission from jets (e.g., Bhattacharya et al 2021;Gulati et al 2023).…”