Exploitation of the IPHAS to Investigate Planetary Nebulae

Abstract

Similar to other classes of astronomical objects, there is a large discrepancy between the total count of theoretically predicted planetary nebulae (PNe) and the number of those actually observed. This discrepancy introduces bias in our attempt to globally understand and characterize the PNe population. Major efforts have been made to find the missing PNe. In particular, the INT Photometric Hα Survey (IPHAS) has, since its debut, provided a whelm of new (candidate) PNe, some of which have been studied in depth using various methodologies such as deep imaging and low- and high-resolution spectroscopy. Here, we present the outcome of the analysis of a first group of these well-investigated IPHAS PNe with a focus on the extended ones. We show that, in general, the missing objects that were expected to be unveiled by the survey (low density, evolved, and distant) are indeed discovered, but the survey also allows the retrieval of “simply” overlooked PNe.

XGAPS: a sub-arcsecond cross-match of Galactic Plane Surveys

“…Owning broad and narrow-band photometric measurements for ≈ 34 million Galactic plane sources, astrometric information, as well as multi-epoch photometry in many of these, the applications for the XGAPS catalogue can be widereaching, especially for the identification of specific source types and related population studies. Examples based on the Gaia/IPHAS catalogue (Scaringi et al 2018) include the discovery of new binary systems (Carrell et al 2022), the selection and identification of Herbig Ae/Be systems (Vioque et al 2020), planetary nebulae (Sabin et al 2022), as well as candidate X-ray emitting binaries (Gandhi et al 2020).…”

XGAPS: a sub-arcsec cross-match of galactic plane surveys

“…All panels also show the decomposition of the distribution employing the Random Forest classifier to select 'good' astrometric targets ( flagRF = 1, blue solid lines) and 'bad' astrometric targets ( flagRF = 0, red solid lines).identification of specific source types and related population studies. Examples based on the Gaia /IPHAS catalogue(Scaringi et al 2018 ) include the disco v ery of new binary systems(Carrell, Gray Cherry & Gillespie 2022 ), the selection, and identification of Herbig Ae/Be systems(Vioque et al 2020 ), planetary nebulae(Sabin et al 2022 ) as well as candidate X-ray emitting binaries(Gandhi et al 2022 ). Further applications may also be found in constructing reliable training sets for classification, as has been used by Gaia Collaboration…”