TY - JOUR
T1 - Population-based identification of H α-excess sources in the Gaia DR2 and IPHAS catalogues
AU - Fratta, M.
AU - Scaringi, S.
AU - Drew, J. E.
AU - Monguió, M.
AU - Knigge, C.
AU - MacCarone, T. J.
AU - Court, J. M.C.
AU - Iłkiewicz, K. A.
AU - Pala, A. F.
AU - Gandhi, P.
AU - Gänsicke, B.
N1 - Publisher Copyright:
© 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.
PY - 2021/7/1
Y1 - 2021/7/1
N2 - We present a catalogue of point-like H α-excess sources in the Northern Galactic Plane. Our catalogue is created using a new technique that leverages astrometric and photomeric information from Gaia to select H α-bright outliers in the INT Photometric H α Survey of the Northern Galactic Plane (IPHAS), across the colour-absolute magnitude diagram. To mitigate the selection biases due to stellar population mixing and to extinction, the investigated objects are first partitioned with respect to their positions in the Gaia colour-absolute magnitude space, and Galactic coordinates space, respectively. The selection is then performed on both partition types independently. Two significance parameters are assigned to each target, one for each partition type. These represent a quantitative degree of confidence that the given source is a reliable H α-excess candidate, with reference to the other objects in the corresponding partition. Our catalogue provides two flags for each source, both indicating the significance level of the H α-excess. By analysing their intensity in the H α narrow band, 28 496 objects out of 7474 835 are identified as H α-excess candidates with a significance higher than 3. The completeness fraction of the H α outliers selection is between 3 and 5 per cent. The suggested 5σ conservative cut yields a purity fraction of 81.9 per cent.
AB - We present a catalogue of point-like H α-excess sources in the Northern Galactic Plane. Our catalogue is created using a new technique that leverages astrometric and photomeric information from Gaia to select H α-bright outliers in the INT Photometric H α Survey of the Northern Galactic Plane (IPHAS), across the colour-absolute magnitude diagram. To mitigate the selection biases due to stellar population mixing and to extinction, the investigated objects are first partitioned with respect to their positions in the Gaia colour-absolute magnitude space, and Galactic coordinates space, respectively. The selection is then performed on both partition types independently. Two significance parameters are assigned to each target, one for each partition type. These represent a quantitative degree of confidence that the given source is a reliable H α-excess candidate, with reference to the other objects in the corresponding partition. Our catalogue provides two flags for each source, both indicating the significance level of the H α-excess. By analysing their intensity in the H α narrow band, 28 496 objects out of 7474 835 are identified as H α-excess candidates with a significance higher than 3. The completeness fraction of the H α outliers selection is between 3 and 5 per cent. The suggested 5σ conservative cut yields a purity fraction of 81.9 per cent.
KW - Emission-line, Be -Hertzsprung-Russell and colour-magnitude - novae, cataclysmic variables
KW - Photometric - catalogues - stars
KW - Techniques
UR - http://www.scopus.com/inward/record.url?scp=85108149148&partnerID=8YFLogxK
U2 - 10.1093/mnras/stab1258
DO - 10.1093/mnras/stab1258
M3 - Article
AN - SCOPUS:85108149148
SN - 0035-8711
VL - 505
SP - 1135
EP - 1152
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 1
ER -