The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products^★

¹ Institute of Astronomy, University of Cambridge, Madingley Road, Cambridge CB3 0HA, UK
e-mail: gil@ast.cam.ac.uk
² INAF – Osservatorio Astrofisico di Arcetri, Largo E. Fermi, 5, 50125 Firenze, Italy
³ GEPI, Observatoire de Paris, PSL Research University, CNRS, Univ. Paris Diderot, Sorbonne Paris Cité, 61 avenue de l’Observatoire, 75014 Paris, France
⁴ Astrophysics Group, Keele University, Keele, Staffordshire ST5 5BG, UK
⁵ Institute for Astronomy, Royal Observatory, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ, UK
⁶ INAF – Osservatorio di Astrofisica e Scienza dello Spazio, via P. Gobetti 93/3, 40129 Bologna, Italy
⁷ Instituto de Astrofísica de Andalucía, CSIC, Glorieta de la Astronomía s/n, Granada 18008, Spain
⁸ Instituto de Astrofísica de Canarias, vía Láctea s/n, 38205 La Laguna, Tenerife, Spain
⁹ Departamento de Astrofísica, Universidad de La Laguna, 38205 La Laguna, Tenerife, Spain
¹⁰ ROB – Royal Observatory of Belgium, Ringlaan 3, 1180 Brussels, Belgium
¹¹ Observational Astrophysics, Division of Astronomy and Space Physics, Department of Physics and Astronomy, Uppsala University, Box 516, 75120 Uppsala, Sweden
¹² Dipartimento di Fisica e Astronomia, Sezione Astrofisica, Universitá di Catania, via S. Sofia 78, 95123 Catania, Italy
¹³ Space Science Data Center – Agenzia Spaziale Italiana, via del Politecnico, s.n.c., 00133 Roma, Italy
¹⁴ Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice cedex 4, France
¹⁵ Nicolaus Copernicus Astronomical Center, Polish Academy of Sciences, ul. Bartycka 18, 00-716 Warsaw, Poland
¹⁶ Institut d’Astronomie et d’Astrophysique, Université Libre de Bruxelles, CP 226, Boulevard du Triomphe, 1050 Bruxelles, Belgium
¹⁷ Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
¹⁸ Lund Observatory, Department of Astronomy and Theoretical Physics, Box 43, 22100 Lund, Sweden
¹⁹ INAF – Osservatorio Asronomico di Palermo, Piazza del Parlamento, 1 90134 Palermo, Italy
²⁰ Astronomy Department, Indiana University, 727 East 3rd St, Bloomington, IN 47405, USA
²¹ Armagh Observatory and Planetarium, College Hill, Armagh BT61 9DG, UK
²² INAF – Osservatorio Astrofisico di Torino, via Osservatorio 20, 10025 Pino Torinese, Italy
²³ Section of Astrophysics, Astronomy and Mechanics, Department of Physics, National and Kapodistrian University of Athens, 15784 Athens, Greece
²⁴ IAASARS, National Observatory of Athens, 15236 Penteli, Greece
²⁵ INAF – Osservatorio Astronomico di Padova, Vicolo dell’Osservatorio 5, 35122 Padova, Italy
²⁶ Institut de Ciències del Cosmos (ICCUB), Universitat de Barcelona (IEEC-UB), Martí i Franquès 1, 08028 Barcelona, Spain
²⁷ Department of Theoretical Physics and Astrophysics, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno, Czech Republic
²⁸ Centro de Astrobiología (CSIC-INTA), Departamento de Astrofísica, campus ESAC. Camino bajo del castillo s/n, 28 692 Villanueva de la Cañada, Madrid, Spain
²⁹ Australian Academy of Science, Box 783, Canberra ACT 2601, Australia
³⁰ GEPI, Observatoire de Paris, Université PSL, CNRS, 5 Place Jules Janssen, 92190 Meudon, France
³¹ Rudolf Peierls Centre for Theoretical Physics, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, UK
³² Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, UK
³³ Institute for Astronomy, University of Edinburgh, Blackford Hill, Edinburgh EH9 3HJ UK
³⁴ Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Alicante, 03690 San Vicente del Raspeig, Alicante, Spain
³⁵ European Space Agency (ESA), European Space Research and Technology Centre (ESTEC), Keplerlaan 1, 2201 AZ Noordwijk, The Netherlands
³⁶ Max-Planck-Institut für Astronomie, Königstuhl 17, 69117 Heidelberg, Germany
³⁷ Niels Bohr International Academy, Niels Bohr Institute, Blegdamsvej 17, 2100 Copenhagen Ø, Denmark
³⁸ School of Physics and Astronomy, Monash University, Wellington Road, Clayton 3800 Victoria, Australia
³⁹ INAF – Osservatorio Astrofisico di Catania, via S. Sofia 78, 95123 Catania, Italy
⁴⁰ Department of Astronomy, Stockholm University, AlbaNova University Center, 106 91 Stockholm, Sweden
⁴¹ ESO – European Organisation for Astronomical Research in the Southern Hemisphere, Alonso de Córdova 3107, Vitacura, 19001 Casilla, Santiago de Chile, Chile
⁴² Instituto de Astrofísica e Ciências do Espaço, Universidade do Porto, CAUP, Rua das Estrelas, 4150-762 Porto, Portugal
⁴³ Observatório Nacional – MCTI (ON), Rua Gal. José Cristino 77, São Cristóvão, 20921-400 Rio de Janeiro, Brazil
⁴⁴ Department of Chemistry and Physics, Saint Mary’s College, Notre Dame, IN 46556, USA
⁴⁵ Leibniz-Institut für Astrophysik Potsdam (AIP), An der Sternwarte 16, 14482 Potsdam, Germany
⁴⁶ Institute of Theoretical Physics and Astronomy, Vilnius University, Sauletekio av. 3, 10257 Vilnius, Lithuania
⁴⁷ Departamento de Física de la Tierra y Astrofísica and IPARCOSUCM (Instituto de Física de Partículas y del Cosmos de la UCM), Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
⁴⁸ Space Sciences, Technologies, and Astrophysics Research (STAR) Institute, Université de Liège, Quartier Agora, Bât B5c, Allée du 6 août, 19c, 4000 Liège, Belgium
⁴⁹ Laboratoire d’Astrophysique de Bordeaux, Univ. Bordeaux, CNRS, B18N, allée Geoffroy Saint-Hilaire, 33615 Pessac, France
⁵⁰ Centro de Astrobiología (CSIC-INTA), Carretera de Ajalvir km 4, 28850 Torrejón de Ardoz, Madrid, Spain
⁵¹ Departamento de Astronomía, Casilla 160-C, Universidad de Concepción, Concepción, Chile
⁵² Instituto de Física y Astronomía, Facultad de Ciencias, Universidad de Valparaíso, Chile
⁵³ Núcleo Milenio Formación Planetaria – NPF, Universidad de Valparaíso, Chile
⁵⁴ INAF – Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monte Porzio Catone (Roma), Italy
⁵⁵ Department of Physics and Astronomy, University of Padova, v. dell’Osservatorio 2, 35122 Padova, Italy
⁵⁶ Theoretical Astrophysics, Department of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
⁵⁷ Núcleo de Astronomía, Facultad de Ingeniería y Ciencias, Universidad Diego Portales, Av. Ejército 441, Santiago, Chile
⁵⁸ Departamento de Ciencias Fisicas, Universidad Andres Bello, Fernandez Concha 700, Las Condes, Santiago, Chile
⁵⁹ Stellar Astrophysics Centre, Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, 8000 Aarhus C, Denmark
⁶⁰ University of Vienna, Dept. Astrophysics, Türkenschanzstrasse 17, 1180 Vienna, Austria
⁶¹ Centro de Astrobiología (INTA-CSIC), Camino Bajo del Castillo s/n, 28692 Villanueva de la Cañada, Madrid, Spain
⁶² Massachusetts Institute of Technology, Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Ave., Cambridge, MA 02139, USA
⁶³ SISSA, via Bonomea 265, 34136 Trieste, Italy
⁶⁴ Dep. of Physics, Sapienza, University of Roma, Roma, Italy
⁶⁵ Research School of Astronomy and Astrophysics, Australian National University, ACT 2611, Australia
⁶⁶ Jeremiah Horrocks Institute, University of Central Lancashire, Preston PR1 2HE, UK
⁶⁷ INAF – Osservatorio Astronomico di Trieste, via G.B. Tiepolo 11, 34143 Trieste, Italy
⁶⁸ Université de Strasbourg, CNRS, Observatoire Astronomique de Strasbourg, UMR 7550, 67000 Strasbourg, France
⁶⁹ The Kavli Institute for Astronomy and Astrophysics at Peking University, 100871 Beijing, PR China
⁷⁰ Instituto de Investigación Multidisciplinario en Ciencia y Tecnología, Universidad de La Serena, Avenida Raúl Bitrán s/n, La Serena, Chile
⁷¹ Departamento de Astronomía, Facultad de Ciencias, Universidad de La Serena, Av. Juan Cisternas 1200, La Serena, Chile
⁷² Max-Planck-Institute for Ex. Physics, Giessenbachstr.1, 85748 Garching, Germany
⁷³ Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg, Mönchhofstr. 12–14, 69120 Heidelberg, Germany
⁷⁴ Materials Science and Applied Mathematics, Malmö University, 205 06 Malmö, Sweden
⁷⁵ Institut UTINAM, CNRS UMR6213, Univ. Bourgogne Franche- Comté, OSU THETA Franche-Comté-Bourgogne, Observatoire de Besançon, BP 1615, 25010 Besançon Cedex, France
⁷⁶ Zentrum für Astronomie der Universität Heidelberg, Landessternwarte, Königstuhl 12, 69117 Heidelberg, Germany
⁷⁷ School of Physics, University of New South Wales, Sydney 2052, Australia
⁷⁸ Dipartimento di Fisica e Astronomia, Università degli Studi di Bologna, via Gobetti 93/2, 40129 Bologna, Italy
⁷⁹ CENTRA, Faculdade de Ciências, Universidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisboa, Portugal
⁸⁰ Departamento de Física e Astronomia, Faculdade de Ciéncias da Universidade do Porto, Portugal
⁸¹ Department of Astronomy, University of Geneva, 51 chemin Pegasi, 1290 Versoix, Switzerland
⁸² Université de Toulouse, Observatoire Midi-Pyrénées, CNRS, IRAP, 14 av. E. Belin, 31400 Toulouse, France
⁸³ Astronomical Institute, CAS, Boční II 1401, 141 00 Prague 4, Czech Republic
⁸⁴ Physics Department, Imperial College London, Prince Consort Road, London SW7 2BZ, UK
⁸⁵ University of Surrey, Physics Department, Guildford GU2 7XH, UK
⁸⁶ Mullard Space Science Laboratory, University College London, Holmbury St Mary, Dorking, Surrey RH5 6NT, UK
⁸⁷ INAF – Astronomical Observatory of Padua, Vicolo dell’Osservatorio, 5, 35122 Padua PD, Italy
⁸⁸ Astronomical Observatory, Institute of Theoretical Physics and Astronomy, Vilnius University, Sauletekio av. 3, 10257 Vilnius, Lithuania
⁸⁹ Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
⁹⁰ Institute of Astrophysics, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Macul, Santiago, Chile
⁹¹ Sorbonne Université, CNRS, UPMC, UMR7095 Institut d’Astrophysique de Paris, 98bis Bd. Arago, 75014 Paris, France
⁹² Department of Physics and Astronomy, Macquarie University, Sydney NSW 2109, Australia

Received: 13 January 2022
Accepted: 10 July 2022

Abstract

Context. The Gaia-ESO Public Spectroscopic Survey is an ambitious project designed to obtain astrophysical parameters and elemental abundances for 100 000 stars, including large representative samples of the stellar populations in the Galaxy, and a well-defined sample of 60 (plus 20 archive) open clusters. We provide internally consistent results calibrated on benchmark stars and star clusters, extending across a very wide range of abundances and ages. This provides a legacy data set of intrinsic value, and equally a large wide-ranging dataset that is of value for the homogenisation of other and future stellar surveys and Gaia's astrophysical parameters.

Aims. This article provides an overview of the survey methodology, the scientific aims, and the implementation, including a description of the data processing for the GIRAFFE spectra. A companion paper introduces the survey results.

Methods. Gaia-ESO aspires to quantify both random and systematic contributions to measurement uncertainties. Thus, all available spectroscopic analysis techniques are utilised, each spectrum being analysed by up to several different analysis pipelines, with considerable effort being made to homogenise and calibrate the resulting parameters. We describe here the sequence of activities up to delivery of processed data products to the ESO Science Archive Facility for open use.

Results. The Gaia-ESO Survey obtained 202 000 spectra of 115 000 stars using 340 allocated VLT nights between December 2011 and January 2018 from GIRAFFE and UVES.

Conclusions. The full consistently reduced final data set of spectra was released through the ESO Science Archive Facility in late 2020, with the full astrophysical parameters sets following in 2022. A companion article reviews the survey implementation, scientific highlights, the open cluster survey, and data products.