摘要：The INT Galactic Plane Survey (IGAPS) is the merger of the optical photometric surveys, IPHAS and UVEX, based on data from theIsaac NewtonTelescope (INT) obtained between 2003 and 2018. Here, we present the IGAPS point source catalogue. It contains 295.4 million rows providing photometry in the filters,i,r, narrow-band Hα,g, andURGO. The IGAPS footprint fills the Galactic coordinate range, |b| < 5° and 30° <ℓ< 215°. A uniform calibration, referred to as the Pan-STARRS system, is applied tog,r, andi, while the Hαcalibration is linked torand then is reconciled via field overlaps. The astrometry in all five bands has been recalculated in the reference frame ofGaiaData Release 2. Down toi ∼ 20 mag (Vega system), most stars are also detected ing,r, and Hα. As exposures in therband were obtained in both the IPHAS and UVEX surveys, typically a few years apart, the catalogue includes two distinctrmeasures,rIandrU. Ther10σlimiting magnitude is approximately 21, with median seeing of 1.1 arcsec. Between approximately 13th and 19th mag in all bands, the photometry is internally reproducible to within 0.02 mag. Stars brighter thanr = 19.5 mag are tested for narrow-band Hαexcess signalling line emission, and for variation exceeding |rI − rU| = 0.2 mag. We find and flag 8292 candidate emission line stars and over 53 000 variables (both at > 5σconfidence).
