Year: 2018
Type: article
Abstract: Context. The Gaia Data Release 2 (DR2) contains more than half a million sources that are identified as variable stars. Aims. We summarise the processing and results of the identification of variable source candidates of RR Lyrae stars, Cepheids, long-period variables (LPVs), rotation modulation (BY Dra-type) stars, δ Scuti and SX Phoenicis stars, and short-timescale variables. In this release we aim to provide useful but not necessarily complete samples of candidates. Methods. The processed Gaia data consist of the G, GBP, and GRP photometry during the first 22 months of operations as well as positions and parallaxes. Various methods from classical statistics, data mining, and time-series analysis were applied and tailored to the specific properties of Gaia data, as were various visualisation tools to interpret the data. Results. The DR2 variability release contains 228 904 RR Lyrae stars, 11 438 Cepheids, 151 761 LPVs, 147 535 stars with rotation modulation, 8882 δ Scuti and SX Phoenicis stars, and 3018 short-timescale variables. These results are distributed over a classification and various Specific Object Studies tables in the Gaia archive, along with the three-band time series and associated statistics for the underlying 550 737 unique sources. We estimate that about half of them are newly identified variables. The variability type completeness varies strongly as a function of sky position as a result of the non-uniform sky coverage and intermediate calibration level of these data. The probabilistic and automated nature of this work implies certain completeness and contamination rates that are quantified so that users can anticipate their effects. Thismeans that even well-known variable sources can be missed or misidentified in the published data. Conclusions. The DR2 variability release only represents a small subset of the processed data. Future releases will include more variable sources and data products; however, DR2 shows the (already) very high quality of the data and great promise for variability studies.
Source: Astronomy and Astrophysics
Authors: B. Holl, M. Audard, K. Nienartowicz, G. Jevardat de Fombelle, O. Marchal, N. Mowlavi, G. Clementini, J. De Ridder, D. W. Evans, L. P. Guy, A. C. Lanzafame, T. Lebzelter, L. Rimoldini, M. Roelens, S. Zucker, E. Distefano, A. Garofalo, I. Lecoeur-Taïbi, M. Lopez, R. Molinaro, T. Muraveva, A. Panahi, S. Regibo, V. Ripepi, L. M. Sarro, C. Aerts, R. I. Anderson, J. Charnas, F. Barblan, S. Blanco-Cuaresma, G. Busso, J. Cuypers, F. De Angeli, F. Glass, M. Grenon, Á. L. Juhász, A. Kochoska, P. Koubsky, A. F. Lanza, S. Leccia, D. Lorenz, M. Marconi, G. Marschalkó, T. Mazeh, S. Messina, F. Mignard, A. Moitinho, L. Molnár, S. Morgenthaler, I. Musella, C. Ordenovic, D. Ordóñez, I. Pagano, L. Palaversa, M. Pawlak, E. Plachy, A. Prša, M. Riello, M. Süveges, L. Szabados, E. Szegedi-Elek, V. Votruba, L. Eyer
Institutions: University of Geneva, Centre National de la Recherche Scientifique, Université Paris Sciences et Lettres, Observatoire de Paris, Galaxies, Etoiles, Physique et Instrumentation, Osservatorio di Astrofisica e Scienza dello Spazio, KU Leuven, University of Cambridge, Large Synoptic Survey Telescope Corporation, University of Catania, Osservatorio Astrofisico di Catania, University of Vienna, Tel Aviv University, University of Bologna, Consejo Superior de Investigaciones Científicas, Centro de Astrobiología, Astronomical Observatory of Capodimonte, National Institute for Astrophysics, Universidad Nacional de Educación a Distancia, Radboud University Nijmegen, European Southern Observatory, Université de Bordeaux, Laboratoire d'Astrophysique de Bordeaux, Center for Astrophysics Harvard & Smithsonian, Royal Observatory of Belgium, Eötvös Loránd University, Konkoly Observatory, HUN-REN Research Centre for Astronomy and Earth Sciences, Hungarian Academy of Sciences, University of Ljubljana, Villanova University, Czech Academy of Sciences, University of Szeged, Université Côte d'Azur, Lagrange Laboratory, Observatoire de la Côte d’Azur, École Polytechnique Fédérale de Lausanne, Charles University, University of Warsaw, Max Planck Institute for Astronomy
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Funders: National Science Foundation, Univerzita Karlova v Praze, European Commission, Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung, Belgian Federal Science Policy Office, Centre National d’Etudes Spatiales, Hungarian Scientific Research Fund, Magyar Tudományos Akadémia, Agenzia Spaziale Italiana, Istituto Nazionale di Astrofisica, Emberi Eroforrások Minisztériuma, Nemzeti Kutatási Fejlesztési és Innovációs Hivatal, Israeli Centers for Research Excellence, Staatssekretariat für Bildung, Forschung und Innovation
Awards: G119750206, G1622653872, G1650595855, G2034387745, G2461764503, Religiosität in der Moderne. Konstruktionsformen, Bedingungen und sozialer Wandel. Eine qualitative und quantitative Studie zu individueller Religiosität in der Schweiz, G2964600887, G308702312, G3125202913, G3163935302, G3502424754, G3657782679, G3743401526, G4214336276, G434337789, G4417133398, G5086802506, G535263259, G5898095075, G6531329289, G6622646236, The obsolescence of the Modern State: the French Example. Origins, Peak and Successor of the Modern State, G7062441703, Les contributions des enseignements de sciences sociales - histoire, géographie, citoyenneté- à l'éducation au développement durable. Etude d'un exemple: le débat en situation scolaire, G8121470152, G8432895945, G954337503
OpenAlex ID: W3098438360