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IGAPS: the merged IPHAS and UVEX optical surveys of the Northern Galactic Plane

Monguió, M. and Greimel, R. and Drew, J. E. and Barentsen, G. and Groot, P. J. and Irwin, M. J. and Casares, J. and Gänsicke, B. T. and Carter, P. J. and Corral-Santana, J. M. and Gentile-Fusillo, N. P. and Greiss, S. and van Haaften, L. M. and Hollands, M. and Jones, D. and Kupfer, T. and Manser, C. J. and Murphy, D. N. A. and McLeod, A. F. and Oosting, T. and Parker, Q. A. and Pyrzas, S. and Rodríguez-Gil, P. and van Roestel, J. and Scaringi, S. and Schellart, P. and Toloza, O. and Vaduvescu, O. and van Spaandonk, L. and Verbeek, K. and Wright, N. J. and Eislöffel, J. and Fabregat, J. and Harris, A. and Morris, R. A. H. and Phillipps, S. and Raddi, R. and Sabin, L. and Unruh, Y. and Vink, J. S and Wesson, R. and Cardwell, A. and Cochrane, R. K. and Doostmohammadi, S. and Mocnik, T. and Stoev, H. and Suárez-Andrés, L. and Tudor, V. and Wilson, T. G. and Zegmott, T. J. (2020) IGAPS: the merged IPHAS and UVEX optical surveys of the Northern Galactic Plane. Astronomy and Astrophysics, 638 . Art. No. A18. ISSN 0004-6361.

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The INT Galactic Plane Survey (IGAPS) is the merger of the optical photometric surveys, IPHAS and UVEX, based on data from the Isaac Newton Telescope (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, and U_(RGO). 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 to g, r, and i, while the Hα calibration is linked to r and then is reconciled via field overlaps. The astrometry in all five bands has been recalculated in the reference frame of Gaia Data Release 2. Down to i ∼ 20 mag (Vega system), most stars are also detected in g, r, and Hα. As exposures in the r band were obtained in both the IPHAS and UVEX surveys, typically a few years apart, the catalogue includes two distinct r measures, r_I and r_U. The r 10σ limiting 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 than r = 19.5 mag are tested for narrow-band Hα excess signalling line emission, and for variation exceeding |r_I − r_U| = 0.2 mag. We find and flag 8292 candidate emission line stars and over 53 000 variables (both at > 5σ confidence).

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van Roestel, J.0000-0002-2626-2872
Additional Information:© 2020 ESO. Article published by EDP Sciences. Received 10 December 2019; Accepted 12 February 2020; Published online 03 June 2020. This work is based on observations made with the Isaac Newton Telescope operated on the island of La Palma by the Isaac Newton Group of Telescopes in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. We would like to take this opportunity to thank directly Marc Balcells (ING Director), Cecilia Fariña, Neil O’Mahony, Javier Méndez, and other members of ING staff who have lent their support to this programme of work over the years, helping to bring it to the finishing line. MM, JED and GB acknowledge the support of research grants funded by the Science, Technology and Facilities Council of the UK (STFC, grants ST/M001008/1 and ST/J001333/1). MM was partially supported by the MINECO (Spanish Ministry of Economy) through grant ESP2016-80079-C2-1-R and RTI2018-095076-B-C21 (MINECO/FEDER, UE), and MDM-2014-0369 of ICCUB (Unidad de Excelencia “María de Maeztu”). RG benefitted from support via STFC grant ST/M001334/1 as a visitor to UCL. PJG acknowledges support from the Netherlands Organisation for Scientific Research (NWO), in contributing to the Isaac Newton Group of Telescopes and through grant 614.000.601. JC acknowldges support by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO) under grant AYA2017-83216-P. DJ and PR-G acknowledge support from the State Research Agency (AEI) of the Spanish Ministry of Science, Innovation and Universities (MCIU) and the European Regional Development Fund (FEDER) under grant AYA2017-83383-P. RR acknowledges funding by the German Science foundation (DFG) through grants HE1356/71-1 and IR190/1-1. We thank Eugene Magnier for providing support on Pan-STARRS data. This research has made use of the University of Hertfordshire high-performance computing facility ( located at the University of Hertfordshire (supported by STFC grants including ST/P000096/1). We thank Martin Hardcastle for his support and expertise in connection with our use of the facility. This work has made use of data from the European Space Agency (ESA) mission Gaia (, processed by the Gaia Data Processing and Analysis Consortium (DPAC, Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Much of the analysis presented has been carried out via TOPCAT and STILTS (Taylor et al. 2006). We thank the referee for comments on this paper that have improved its content.
Funding AgencyGrant Number
Science and Technology Facilities Council (STFC)ST/M001008/1
Science and Technology Facilities Council (STFC)ST/J001333/1
Ministerio de Economía, Industria y Competitividad (MINECO)ESP2016-80079-C2-1-R
Ministerio de Economía, Industria y Competitividad (MINECO)RTI2018-095076-B-C21
Ministerio de Economía, Industria y Competitividad (MINECO)MDM-2014-0369
Science and Technology Facilities Council (STFC)ST/M001334/1
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)614.000.601
Ministerio de Economía, Industria y Competitividad (MINECO)AYA2017-83216-P
Ministerio de Ciencia, Innovación y Universidades (MCIU)UNSPECIFIED
European Regional Development FundAYA2017-83383-P
Deutsche Forschungsgemeinschaft (DFG)HE1356/71-1
Deutsche Forschungsgemeinschaft (DFG)IR190/1-1
Science and Technology Facilities Council (STFC)ST/P000096/1
Gaia Multilateral AgreementUNSPECIFIED
Subject Keywords:stars: general – stars: evolution – Galaxy: disc – surveys – catalogues
Record Number:CaltechAUTHORS:20200414-093852590
Persistent URL:
Official Citation:IGAPS: the merged IPHAS and UVEX optical surveys of the northern Galactic plane. M. Monguió, R. Greimel, J. E. Drew, G. Barentsen, P. J. Groot, M. J. Irwin, J. Casares, B. T. Gänsicke, P. J. Carter, J. M. Corral-Santana, N. P. Gentile-Fusillo, S. Greiss, L. M. van Haaften, M. Hollands, D. Jones, T. Kupfer, C. J. Manser, D. N. A. Murphy, A. F. McLeod, T. Oosting, Q. A. Parker, S. Pyrzas, P. Rodríguez-Gil, J. van Roestel, S. Scaringi, P. Schellart, O. Toloza, O. Vaduvescu, L. van Spaandonk, K. Verbeek, N. J. Wright, J. Eislöffel, J. Fabregat, A. Harris, R. A. H. Morris, S. Phillipps, R. Raddi, L. Sabin, Y. Unruh, J. S. Vink, R. Wesson, A. Cardwell, A. de Burgos, R. K. Cochrane, S. Doostmohammadi, T. Mocnik, H. Stoev, L. Suárez-Andrés, V. Tudor, T. G. Wilson and T. J. Zegmott. A&A, 638 (2020) A18; DOI:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:102526
Deposited By: Tony Diaz
Deposited On:14 Apr 2020 16:54
Last Modified:03 Jun 2020 19:52

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