Author: "Gilmore, G." / Topic: milky way - Searchworks@Jio Institute Digital Library Search Results

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93 results on '"Gilmore, G."'

1. Gaia-ESO Survey: Chemical evolution of Mg and Al in the Milky Way with machine learning.

Author: Ambrosch, M., Guiglion, G., Mikolaitis, Š., Chiappini, C., Tautvaišiené, G., Nepal, S., Gilmore, G., Randich, S., Bensby, T., Bayo, A., Bergemann, M., Morbidelli, L., Pancino, E., Sacco, G. G., Smiljanic, R., Zaggia, S., Jofré, P., and Jiménez-Esteban, F. M.
Subjects: MACHINE learning, MILKY Way, CONVOLUTIONAL neural networks, STELLAR populations, DATA release, STELLAR spectra
Abstract: Context. To take full advantage of upcoming large-scale spectroscopic surveys, it will be necessary to parameterize millions of stellar spectra in an effcient way. Machine learning methods, especially convolutional neural networks (CNNs), will be among the main tools geared at achieving this task. Aims. We aim to prepare the groundwork for machine learning techniques for the next generation of spectroscopic surveys, such as 4MOST and WEAVE. Our goal is to show that CNNs can predict accurate stellar labels from relevant spectral features in a physically meaningful way. The predicted labels can be used to investigate properties of the Milky Way galaxy. Methods. We built a neural network and trained it on GIRAFFE spectra with their associated stellar labels from the sixth internal Gaia-ESO data release. Our network architecture contains several convolutional layers that allow the network to identify absorption features in the input spectra. The internal uncertainty was estimated from multiple network models. We used the t-distributed stochastic neighbor embedding tool to remove bad spectra from our training sample. Results. Our neural network is able to predict the atmospheric parameters Te and log(g) as well as the chemical abundances [Mg/Fe], [Al/Fe], and [Fe/H] for 36 904 stellar spectra. The training precision is 37K for Te, 0.06 dex for log(g), 0.05 dex for [Mg/Fe], 0.08 dex for [Al/Fe], and 0.04 dex for [Fe/H]. Network gradients reveal that the network is inferring the labels in a physically meaningful way from spectral features. We validated our methodology using benchmark stars and recovered the properties of different stellar populations in the Milky Way galaxy. Conclusions. Such a study provides very good insights into the application of machine learning for the analysis of large-scale spectroscopic surveys, such as WEAVE and 4MOST MilkyWay disk and bulge low- and high-resolution (4MIDABLE-LR and -HR). The community will have to put substantial efforts into building proactive training sets for machine learning methods to minimize any possible systematics. [ABSTRACT FROM AUTHOR]
Published: 2023
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2. The Gaia-ESO Survey: Preparing the ground for 4MOST and WEAVE galactic surveys: Chemical evolution of lithium with machine learning.

Author: Nepal, S., Guiglion, G., de Jong, R. S., Valentini, M., Chiappini, C., Steinmetz, M., Ambrosch, M., Pancino, E., Jeffries, R. D., Bensby, T., Romano, D., Smiljanic, R., Dantas, M. L. L., Gilmore, G., Randich, S., Bayo, A., Bergemann, M., Franciosini, E., Jiménez-Esteban, F., and Jofré, P.
Subjects: LITHIUM, MACHINE learning, CONVOLUTIONAL neural networks, AGE of stars, GALACTIC evolution, MILKY Way, COSMIC rays
Abstract: Context. With its origin coming from several sources (Big Bang, stars, cosmic rays) and given its strong depletion during its stellar lifetime, the lithium element is of great interest as its chemical evolution in the Milky Way is not well understood at present. To help constrain stellar and galactic chemical evolution models, numerous and precise lithium abundances are necessary for a large range of evolutionary stages, metallicities, and Galactic volume. Aims. In the age of stellar parametrization on industrial scales, spectroscopic surveys such as APOGEE, GALAH, RAVE, and LAMOST have used data-driven methods to rapidly and precisely infer stellar labels (atmospheric parameters and abundances). To prepare the ground for future spectroscopic surveys such as 4MOST and WEAVE, we aim to apply machine learning techniques to lithium measurements and analyses. Methods. We trained a convolution neural network (CNN), coupling Gaia-ESO Survey iDR6 stellar labels (Teff, log(g), [Fe/H], and A(Li)) and GIRAFFE HR15N spectra, to infer the atmospheric parameters and lithium abundances for ∼40 000 stars. The CNN architecture and accompanying notebooks are available online via GitHub. Results. We show that the CNN properly learns the physics of the stellar labels, from relevant spectral features through a broad range of evolutionary stages and stellar parameters. The lithium feature at 6707.8 Å is successfully singled out by our CNN, among the thousands of lines in the GIRAFFE HR15N setup. Rare objects such as lithium-rich giants are found in our sample. This level of performance is achieved thanks to a meticulously built, high-quality, and homogeneous training sample. Conclusions. The CNN approach is very well adapted for the next generations of spectroscopic surveys aimed at studying (among other elements) lithium, such as the 4MIDABLE-LR/HR (4MOST Milky Way disk and bulge low- and high-resolution) surveys. In this context, the caveats of machine-learning applications should be appropriately investigated, along with the realistic label uncertainties and upper limits for abundances. [ABSTRACT FROM AUTHOR]
Published: 2023
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3. Gaia Early Data Release 3 Structure and properties of the Magellanic Clouds

Author: Gaia Collaboration, Luri, X., Chemin, L., Clementini, G., Delgado, H. E., McMillan, P. J., Romero-Gómez, M., Balbinot, E., Castro-Ginard, A., Mor, R., Ripepi, V., Sarro, L. M., Cioni, M. -R. L., Fabricius, C., Garofalo, A., Helmi, A., Muraveva, T., Brown, A. G. A., Vallenari, A., Prusti, T., de, J. H. J., Babusiaux, C., Biermann, M., Creevey, O. L., Evans, D. W., Eyer, L., Hutton, A., Jansen, F., Jordi, C., Klioner, S. A., Lammers, U., Lindegren, L., Mignard, F., Panem, C., Pourbaix, D., Randich, S., Sartoretti, P., Soubiran, C., Walton, N. A., Arenou, F., Bailer-Jones, C. A. L., Bastian, U., Cropper, M., Drimmel, R., Katz, D., Lattanzi, M. G., van Leeuwen, F., Bakker, J., Castañeda, J., De, F., Ducourant, C., Fouesneau, M., Frémat, Y., Guerra, R., Guerrier, A., Guiraud, J., Jean-Antoine, A., Masana, E., Messineo, R., Mowlavi, N., Nicolas, C., Nienartowicz, K., Pailler, F., Panuzzo, P., Riclet, F., Roux, W., Seabroke, G. M., Sordo, R., Tanga, P., Thévenin, F., Gracia-Abril, G., Portell, J., Teyssier, D., Altmann, M., Andrae, R., Bellas-Velidis, I., Benson, K., Berthier, J., Blomme, R., Brugaletta, E., Burgess, P. W., Busso, G., Carry, B., Cellino, A., Cheek, N., Damerdji, Y., Davidson, M., Delchambre, L., Dell'Oro, A., Fernández-Hernández, J., Galluccio, L., García-Lario, P., Garcia-Reinaldos, M., González-Núñez, J., Gosset, E., Haigron, R., Halbwachs, J. -L., Hambly, N. C., Harrison, D. L., Hatzidimitriou, D., Heiter, U., Hernández, J., Hestroffer, D., Hodgkin, S. T., Holl, B., Janßen, K., de Fombelle, G. Jevardat, Jordan, S., Krone-Martins, A., Lanzafame, A. C., Löffler, W., Lorca, A., Manteiga, M., Marchal, O., Marrese, P. M., Moitinho, A., Mora, A., Muinonen, K., Osborne, P., Pancino, E., Pauwels, T., Recio-Blanco, A., Richards, P. J., Riello, M., Rimoldini, L., Robin, A. C., Roegiers, T., Rybizki, J., Siopis, C., Smith, M., Sozzetti, A., Ulla, A., Utrilla, E., van Leeuwen, M., van Reeven, W., Abbas, U., Abreu, A., Accart, S., Aerts, C., Aguado, J. J., Ajaj, M., Altavilla, G., Álvarez, M. A., Cid-Fuentes, J. Álvarez, Alves, J., Anderson, R. I., Varela, E. Anglada, Antoja, T., Audard, M., Baines, D., Baker, S. G., Balaguer-Núñez, L., Balog, Z., Barache, C., Barbato, D., Barros, M., Barstow, M. A., Bartolomé, S., Bassilana, J. -L., Bauchet, N., Baudesson-Stella, A., Becciani, U., Bellazzini, M., Bernet, M., Bertone, S., Bianchi, L., Blanco-Cuaresma, S., Boch, T., Bombrun, A., Bossini, D., Bouquillon, S., Bragaglia, A., Bramante, L., Breedt, E., Bressan, A., Brouillet, N., Bucciarelli, B., Burlacu, A., Busonero, D., Butkevich, A. G., Buzzi, R., Caffau, E., Cancelliere, R., Cánovas, H., Cantat-Gaudin, T., Carballo, R., Carlucci, T., Carnerero, M. I, Carrasco, J. M., Casamiquela, L., Castellani, M., Sampol, P. Castro, Chaoul, L., Charlot, P., Chiavassa, A., Comoretto, G., Cooper, W. J., Cornez, T., Cowell, S., Crifo, F., Crosta, M., Crowley, C., Dafonte, C., Dapergolas, A., David, M., David, P., de Laverny, P., De Luise, F., De March, R., De Ridder, J., de Souza, R., de Teodoro, P., de Torres, A., del Peloso, E. F., del Pozo, E., Delgado, A., Delisle, J. -B., Di Matteo, P., Diakite, S., Diener, C., Distefano, E., Dolding, C., Eappachen, D., Enke, H., Esquej, P., Fabre, C., Fabrizio, M., Faigler, S., Fedorets, G., Fernique, P., Fienga, A., Figueras, F., Fouron, C., Fragkoudi, F., Fraile, E., Franke, F., Gai, M., Garabato, D., Garcia-Gutierrez, A., García-Torres, M., Gavras, P., Gerlach, E., Geyer, R., Giacobbe, P., Gilmore, G., Girona, S., Giuffrida, G., Gomez, A., Gonzalez-Santamaria, I., González-Vidal, J. J., Granvik, M., Gutiérrez-Sánchez, R., Guy, L. P., Hauser, M., Haywood, M., Hidalgo, S. L., Hilger, T., Hładczuk, N., Hobbs, D., Holland, G., Huckle, H. E., Jasniewicz, G., Jonker, P. G., Juaristi, J., Julbe, F., Karbevska, L., Kervella, P., Khanna, S., Kochoska, A., Kontizas, M., Kordopatis, G., Korn, A. J., Kostrzewa-Rutkowska, Z., Kruszyńska, K., Lambert, S., Lanza, A. F., Lasne, Y., Campion, J. -F. Le, Fustec, Y. Le, Lebreton, Y., Lebzelter, T., Leccia, S., Leclerc, N., Lecoeur-Taibi, I., Liao, S., Licata, E., Lindstrøm, H. E. P., Lister, T. A., Livanou, E., Lobel, A., Madrero, P., Managau, S., Mann, R. G., Marchant, J. M., Marconi, M., Marcos, M. M. S., Marinoni, S., Marocco, F., Marshall, D. J., Polo, L. Martin, Martín-Fleitas, J. M., Masip, A., Massari, D., Mastrobuono-Battisti, A., Mazeh, T., Messina, S., Michalik, D., Millar, N. R., Mints, A., Molina, D., Molinaro, R., Molnár, L., Montegriffo, P., Morbidelli, R., Morel, T., Morris, D., Mulone, A. F., Munoz, D., Murphy, C. P., Musella, I., Noval, L., Ordénovic, C., Orrù, G., Osinde, J., Pagani, C., Pagano, I., Palaversa, L., Palicio, P. A., Panahi, A., Pawlak, M., Peñalosa, X., Penttilä, A., Piersimoni, A. M., Pineau, F. -X., Plachy, E., Plum, G., Poggio, E., Poretti, E., Poujoulet, E., Prša, A., Pulone, L., Racero, E., Ragaini, S., Rainer, M., Raiteri, C. M., Rambaux, N., Ramos, P., Ramos-Lerate, M., Re, P., Regibo, S., Reylé, C., Riva, A., Rixon, G., Robichon, N., Robin, C., Roelens, M., Rohrbasser, L., Rowell, N., Royer, F., Rybicki, K. A., Sadowski, G., Sagristà, A., Sahlmann, J., Salgado, J., Salguero, E., Samaras, N., Sanchez, V., Sanna, N., Santoveña, R., Sarasso, M., Schultheis, M., Sciacca, E., Segol, M., Segovia, J. C., Ségransan, D., Semeux, D., Siddiqui, H. I., Siebert, A., Siltala, L., Slezak, E., Smart, R. L., Solano, E., Solitro, F., Souami, D., Souchay, J., Spagna, A., Spoto, F., Steele, I. A., Steidelmüller, H., Stephenson, C. A., Süveges, M., Szabados, L., Szegedi-Elek, E., Taris, F., Tauran, G., Taylor, M. B., Teixeira, R., Thuillot, W., Tonello, N., Torra, F., Torra, J., Turon, C., Unger, N., Vaillant, M., van, E., Vanel, O., Vecchiato, A., Viala, Y., Vicente, D., Voutsinas, S., Weiler, M., Wevers, T., Wyrzykowski, Ł., Yoldas, A., Yvard, P., Zhao, H., Zorec, J., Zucker, S., Zurbach, C., Zwitter, T., Institut de Ciencies del Cosmos (ICCUB), Universitat de Barcelona (UB), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - 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CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France -Institut national des sciences de l'Univers (INSU - CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université Grenoble Alpes (UGA)-Météo-France, Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud]), Laboratoire d'études spatiales et d'instrumentation en astrophysique = Laboratory of Space Studies and Instrumentation in Astrophysics (LESIA), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Centro de Excelencia Científica Severo Ochoa, Instituto de Ciencias del Cosmos de la Universidad de Barcelona, SEV2015-0493, Unidad de Excelencia Científica María de Maeztu Centro de Astrobiología del Instituto Nacional de Técnica Aeroespacial y CSIC, MDM-2014-0369, Krone Martins, A. [0000-0002-2308-6623], Seabroke, G. [0000-0003-4072-9536], Chiavassa, A. [0000-0003-3891-7554], Castro Ginard, A. [0000-0002-9419-3725], McMillan, P. [0000-0002-8861-2620], Siltala, L. [0000-0002-6938-794X], Delise, J. B. [0000-0001-5844-9888], Aerts, C. [0000-0003-1822-7126], Fedorets, G. [0000-0002-8418-4809], Forderung der wissenschaftlichen Forschung (FWF), Belgian federal Science Policy Office (BELSPO), Hertha Firnberg Programme, Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Comite Francais d'Evaluation de la Cooperation Universitaire et Scientifique avec le Bresil (COFECUB), National Natural Science Foundation of China (NSFC), China Scholarship Council (CSC), European Commission (EC), European Research Council (ERC), Agence Nationale de la Recherche (ANR), European Space Agency (ESA), Centre National D'Etudes Spatiales (CNES), Istituto Nazionale di Astrofisica (INAF), Ministero dell'Istruzione, dell'Università e della Ricerca (MIUR), Narodowe Centrum Nauki (NCN), Fundacao para a Ciencia e a Tecnologia (FCT), Slovenian Research Agency, Agencia Estatal de Investigación (AEI), Swedish National Space Agency (SNSA), United Kingdom Science and Technology Facilities Council (STFC), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Gaia Collaboration, and ITA
Subjects: Astronomy, Astrophysics, Kinematics, APPROXIMATE BAYESIAN COMPUTATION, 01 natural sciences, BRIDGE, STELLAR POPULATIONS, Astronomi, astrofysik och kosmologi, OVERDENSITY, morphology, Magellanic Clouds, Astronomy, Astrophysics and Cosmology, Limit (mathematics), bridge, 010303 astronomy & astrophysics, Physics, education.field_of_study, Astrophysics of Galaxies, Parallaxes, Astrophysics::Instrumentation and Methods for Astrophysics, stellar populations, overdensity, Astrometry, Galaxies: Magellanic Clouds, field, kinematics, Physical Sciences, parallaxes, astrometry, catalogs, proper motions, Astrophysics - Astrophysics of Galaxies, Data release, VMC SURVEY, stars, Milky Way, astro-ph.GA, Population, Structure (category theory), FOS: Physical sciences, Astronomy & Astrophysics, system, Computer Science::Digital Libraries, vmc survey, Settore FIS/05 - Astronomia e Astrofisica, Proper Motions, 0103 physical sciences, KINEMATICS, FIELD, education, Science & Technology, 010308 nuclear & particles physics, Astronomy and Astrophysics, 115 Astronomy, Space science, Physics::History of Physics, Stars, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), MORPHOLOGY, Catalogs, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], SYSTEM, STARS, approximate bayesian computation
Abstract: Context. This work is part of the Gaia Data Processing and Analysis Consortium papers published with the Gaia Early Data Release 3 (EDR3). It is one of the demonstration papers aiming to highlight the improvements and quality of the newly published data by applying them to a scientific case., Aims. We use the Gaia EDR3 data to study the structure and kinematics of the Magellanic Clouds. The large distance to the Clouds is a challenge for the Gaia astrometry. The Clouds lie at the very limits of the usability of the Gaia data, which makes the Clouds an excellent case study for evaluating the quality and properties of the Gaia data., Methods. The basis of our work are two samples selected to provide a representation as clean as possible of the stars of the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC). The selection used criteria based on position, parallax, and proper motions to remove foreground contamination from the Milky Way, and allowed the separation of the stars of both Clouds. From these two samples we defined a series of subsamples based on cuts in the colour-magnitude diagram; these subsamples were used to select stars in a common evolutionary phase and can also be used as approximate proxies of a selection by age., Results. We compared the Gaia Data Release 2 and Gaia EDR3 performances in the study of the Magellanic Clouds and show the clear improvements in precision and accuracy in the new release. We also show that the systematics still present in the data make the determination of the 3D geometry of the LMC a difficult endeavour; this is at the very limit of the usefulness of the Gaia EDR3 astrometry, but it may become feasible with the use of additional external data. We derive radial and tangential velocity maps and global profiles for the LMC for the several subsamples we defined. To our knowledge, this is the first time that the two planar components of the ordered and random motions are derived for multiple stellar evolutionary phases in a galactic disc outside the Milky Way, showing the differences between younger and older phases. We also analyse the spatial structure and motions in the central region, the bar, and the disc, providing new insightsinto features and kinematics. Finally, we show that the Gaia EDR3 data allows clearly resolving the Magellanic Bridge, and we trace the density and velocity flow of the stars from the SMC towards the LMC not only globally, but also separately for young and evolved populations. This allows us to confirm an evolved population in the Bridge that is slightly shift from the younger population. Additionally, we were able to study the outskirts of both Magellanic Clouds, in which we detected some well-known features and indications of new ones.
Published: 2021

4. Gaia Data Release 2. Kinematics of globular clusters and dwarf galaxies around the Milky Way

Author: Helmi, A., van Leeuwen, F., McMillan, P. J., Massari, D., Antoja, T., Robin, A. C., Lindegren, L., Bastian, U., Arenou, F., Babusiaux, C., Biermann, M., Breddels, M. A., Hobbs, D., Jordi, C., Pancino, E., Reyle, C., Veljanoski, J., Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., Bailer-Jones, C. A. L., Evans, D. W., Eyer, L., Jansen, F., Klioner, S. A., Lammers, U., Luri, X., Mignard, F., Panem, C., Pourbaix, D., Randich, S., Sartoretti, P., Siddiqui, H. I., Soubiran, C., Walton, N. A., Cropper, M., Drimmel, R., Katz, D., Lattanzi, M. G., Bakker, J., Cacciari, C., Castaneda, J., Chaoul, L., Cheek, N., De Angeli, F., Fabricius, C., Guerra, R., Holl, B., Masana, E., Messineo, R., Mowlavi, N., Nienartowicz, K., Panuzzo, P., Portell, J., Riello, M., Seabroke, G. M., Tanga, P., Thevenin, F., Gracia-Abril, G., Comoretto, G., Garcia-Reinaldos, M., Teyssier, D., Altmann, M., Andrae, R., Audard, M., Bellas-Velidis, I., Benson, K., Berthier, J., Blomme, R., Burgess, P., Busso, G., Carry, B., Cellino, A., Clementini, G., Clotet, M., Creevey, O., Davidson, M., De Ridder, J., Delchambre, L., Dell'Oro, A., Ducourant, C., Fernandez-Hernandez, J., Fouesneau, M., Fremat, Y., Galluccio, L., Garcia-Torres, M., Gonzalez-Nunez, J., Gonzalez-Vidal, J. J., Gosset, E., Guy, L. P., Halbwachs, J. -L., Hambly, N. C., Harrison, D. L., Hernandez, J., Hestroffer, D., Hodgkin, S. T., Hutton, A., Jasniewicz, G., Jean-Antoine-Piccolo, A., Jordan, S., Korn, A. J., Krone-Martins, A., Lanzafame, A. C., Lebzelter, T., Loeffler, W., Manteiga, M., Marrese, P. M., Martin-Fleitas, J. M., Moitinho, A., Mora, A., Muinonen, K., Osinde, J., Pauwels, T., Petit, J. -M., Recio-Blanco, A., Richards, P. J., Rimoldini, L., Sarro, L. M., Siopis, C., Smith, M., Sozzetti, A., Sueveges, M., Torra, J., van Reeven, W., Abbas, U., Abreu Aramburu, A., Accart, S., Aerts, C., Altavilla, G., Alvarez, M. A., Alvarez, R., Alves, J., Anderson, R. I., Andrei, A. H., Anglada Varela, E., Antiche, E., Arcay, B., Astraatmadja, T. L., Bach, N., Baker, S. G., Balaguer-Nunez, L., Balm, P., Barache, C., Barata, C., Barbato, D., Barblan, F., Barklem, P. S., Barrado, D., Barros, M., Barstow, M. A., Bartholome Munoz, S., Bassilana, J. -L., Becciani, U., Bellazzini, M., Berihuete, A., Bertone, S., Bianchi, L., Bienayme, O., Blanco-Cuaresma, S., Boch, T., Boeche, C., Bombrun, A., Borrachero, R., Bossini, D., Bouquillon, S., Bourda, G., Bragaglia, A., Bramante, L., Bressan, A., Brouillet, N., Bruesemeister, T., Brugaletta, E., Bucciarelli, B., Burlacu, A., Busonero, D., Butkevich, A. G., Buzzi, R., Caffau, E., Cancelliere, R., Cannizzaro, G., Cantat-Gaudin, T., Carballo, R., Carlucci, T., Carrasco, J. M., Casamiquela, L., Castellani, M., Castro-Ginard, A., Charlot, P., Chemin, L., Chiavassa, A., Cocozza, G., Costigan, G., Cowell, S., Crifo, F., Crosta, M., Crowley, C., Cuypers, J., Dafonte, C., Damerdji, Y., Dapergolas, A., David, P., David, M., de Laverny, P., De Luise, F., De March, R., de Martino, D., de Souza, R., de Torres, A., Debosscher, J., del Pozo, E., Delbo, M., Delgado, A., Delgado, H. E., Di Matteo, P., Diakite, S., Diener, C., Distefano, E., Dolding, C., Drazinos, P., Duran, J., Edvardsson, B., Enke, H., Eriksson, K., Esquej, P., Bontemps, G. Eynard, Fabre, C., Fabrizio, M., Faigler, S., Falcao, A. J., Farras Casas, M., Federici, L., Fedorets, G., Fernique, P., Figueras, F., Filippi, F., Findeisen, K., Fonti, A., Fraile, E., Fraser, M., Frezouls, B., Gai, M., Galleti, S., Garabato, D., Garcia-Sedano, F., Garofalo, A., Garralda, N., Gavel, A., Gavras, P., Gerssen, J., Geyer, R., Giacobbe, P., Gilmore, G., Girona, S., Giuffrida, G., Glass, F., Gomes, M., Granvik, M., Gueguen, A., Guerrier, A., Guiraud, J., Gutierrez-Sanchez, R., Hofmann, W., Holland, G., Huckle, H. E., Hypki, A., Icardi, V., Janssen, K., de Fombelle, G. Jevardat, Jonker, P. G., Juhasz, A. L., Julbe, F., Karampelas, A., Kewley, A., Klar, J., Kochoska, A., Kohley, R., Kolenberg, K., Kontizas, M., Kontizas, E., Koposov, S. E., Kordopatis, G., Kostrzewa-Rutkowska, Z., Koubsky, P., Lambert, S., Lanza, A. F., Lasne, Y., Lavigne, J. -B., Le Fustec, Y., Le Poncin-Lafitte, C., Lebreton, Y., Leccia, S., Leclerc, N., Lecoeur-Taibi, I., Lenhardt, H., Leroux, F., Liao, S., Licata, E., Lindstrom, H. E. P., Lister, T. A., Livanou, E., Lobel, A., Lopez, M., Managau, S., Mann, R. G., Mantelet, G., Marchal, O., Marchant, J. M., Marconi, M., Marinoni, S., Marschalko, G., Marshall, D. J., Martino, M., Marton, G., Mary, N., Matijevic, G., Mazeh, T., Messina, S., Michalik, D., Millar, N. R., Molina, D., Molinaro, R., Molnar, L., Montegriffo, P., Mor, R., Morbidelli, R., Morel, T., Morris, D., Mulone, A. F., Muraveva, T., Musella, I., Nelemans, G., Nicastro, L., Noval, L., O'Mullane, W., Ordenovic, C., Ordonez-Blanco, D., Osborne, P., Pagani, C., Pagano, I., Pailler, F., Palacin, H., Palaversa, L., Panahi, A., Pawlak, M., Piersimoni, A. M., Pineau, F. -X., Plachy, E., Plum, G., Poggio, E., Poujoulet, E., Prsa, A., Pulone, L., Racero, E., Ragaini, S., Rambaux, N., Ramos-Lerate, M., Regibo, S., Riclet, F., Ripepi, V., Riva, A., Rivard, A., Rixon, G., Roegiers, T., Roelens, M., Romero-Gomez, M., Rowell, N., Royer, F., Ruiz-Dern, L., Sadowski, G., Selles, T. Sagrista, Sahlmann, J., Salgado, J., Salguero, E., Sanna, N., Santana-Ros, T., Sarasso, M., Savietto, H., Schultheis, M., Sciacca, E., Segol, M., Segovia, J. C., Segransan, D., Shih, I-C., Siltala, L., Silva, A. F., Smart, R. L., Smith, K. W., Solano, E., Solitro, F., Sordo, R., Soria Nieto, S., Souchay, J., Spagna, A., Spoto, F., Stampa, U., Steele, I. A., Steidelmueller, H., Stephenson, C. A., Stoev, H., Suess, F. F., Surdej, J., Szabados, L., Szegedi-Elek, E., Tapiador, D., Taris, F., Tauran, G., Taylor, M. B., Teixeira, R., Terrett, D., Teyssandier, P., Thuillot, W., Titarenko, A., Torra Clotet, F., Turon, C., Ulla, A., Utrilla, E., Uzzi, S., Vaillant, M., Valentini, G., Valette, V., van Elteren, A., Van Hemelryck, E., van Leeuwen, M., Vaschetto, M., Vecchiato, A., Viala, Y., Vicente, D., Vogt, S., von Essen, C., Voss, H., Votruba, V., Voutsinas, S., Walmsley, G., Weiler, M., Wertz, O., Wevems, T., Wyrzykowski, L., Yoldas, A., Zerjal, M., Ziaeepour, H., Zorec, J., Zschocke, S., Zucker, S., Zurbach, C., Zwitter, T., Collaboration, Gaia, Universidad de Cantabria, Gaia Collaboration, Astronomy, Kapteyn Astronomical Institute, Apollo - University of Cambridge Repository, Helmi, A., Van Leeuwen, F., McMillan, P.J., Massari, D., Antoja, T., Robin, A.C., Lindegren, L., Bastian, U., Arenou, F., Babusiaux, C., Biermann, M., Breddels, M.A., Hobbs, D., Jordi, C., Pancino, E., Reylé, C., Veljanoski, J., Brown, A.G.A., Vallenari, A., Prusti, T., De Bruijne, J.H.J., Bailer-Jones, C.A.L., Evans, D.W., Eyer, L., Jansen, F., Klioner, S.A., Lammers, U., Luri, X., Mignard, F., Panem, C., Pourbaix, D., Randich, S., Sartoretti, P., Siddiqui, H.I., Soubiran, C., Walton, N.A., Cropper, M., Drimmel, R., Katz, D., Lattanzi, M.G., Bakker, J., Cacciari, C., Castañeda, J., Chaoul, L., Cheek, N., De Angeli, F., Fabricius, C., Guerra, R., Holl, B., Masana, E., Messineo, R., Mowlavi, N., Nienartowicz, K., Panuzzo, P., Portell, J., Riello, M., Seabroke, G.M., Tanga, P., Thévenin, F., Gracia-Abril, G., Comoretto, G., Teyssier, D., Garcia-Reinaldos, M., Altmann, M., Andrae, R., Audard, M., Bellas-Velidis, I., Benson, K., Berthier, J., Blomme, R., Burgess, P., Busso, G., Carry, B., Cellino, A., Clementini, G., Clotet, M., Creevey, O., Davidson, M., De Ridder, J., Delchambre, L., Dell'Oro, A., Ducourant, C., Fernández-Hernández, J., Fouesneau, M., Frémat, Y., Galluccio, L., García-Torres, M., González-Núñez, J., González-Vidal, J.J., Gosset, E., Guy, L.P., Halbwachs, J.-L., Hambly, N.C., Harrison, D.L., Hernández, J., Hestroffer, D., Hodgkin, S.T., Hutton, A., Jasniewicz, G., Jean-Antoine-Piccolo, A., Jordan, S., Korn, A.J., Krone-Martins, A., Lanzafame, A.C., Lebzelter, T., Löffler, W., Manteiga, M., Marrese, P.M., Martín-Fleitas, J.M., Moitinho, A., Mora, A., Muinonen, K., Osinde, J., Pauwels, T., Petit, J.-M., Recio-Blanco, A., Richards, P.J., Rimoldini, L., Sarro, L.M., Siopis, C., Smith, M., Sozzetti, A., Söveges, M., Torra, J., Van Reeven, W., Abreu Aramburu, A., Abbas, U., Accart, S., Aerts, C., Altavilla, G., Álvarez, M.A., Alvarez, R., Alves, J., Anderson, R.I., Andrei, A.H., Anglada Varela, E., Antiche, E., Arcay, B., Astraatmadja, T.L., Bach, N., Baker, S.G., Balaguer-Núñez, L., Balm, P., Barache, C., Barata, C., Barbato, D., Barblan, F., Barklem, P.S., Barrado, D., Barros, M., Barstow, M.A., Bartholomé Muñoz, S., Bassilana, J.-L., Becciani, U., Bellazzini, M., Berihuete, A., Bertone, S., Bianchi, L., Bienaymé, O., Blanco-Cuaresma, S., Boch, T., Boeche, C., Bombrun, A., Borrachero, R., Bossini, D., Bouquillon, S., Bourda, G., Bragaglia, A., Bramante, L., Bressan, A., Brouillet, N., Brösemeister, T., Brugaletta, E., Bucciarelli, B., Burlacu, A., Busonero, D., Butkevich, A.G., Buzzi, R., Caffau, E., Cancelliere, R., Cannizzaro, G., Cantat-Gaudin, T., Carballo, R., Carlucci, T., Carrasco, J.M., Casamiquela, L., Castellani, M., Castro-Ginard, A., Charlot, P., Chiavassa, A., Chemin, L., Cocozza, G., Costigan, G., Cowell, S., Crifo, F., Crosta, M., Crowley, C., Cuypersy, J., Dafonte, C., Damerdji, Y., Dapergolas, A., David, P., David, M., De Laverny, P., De Luise, F., De March, R., De Martino, D., De Souza, R., De Torres, A., Debosscher, J., Del Pozo, E., Delbo, M., Delgado, A., Delgado, H.E., Di Matteo, P., Diakite, S., Diener, C., Distefano, E., Dolding, C., Drazinos, P., Durán, J., Edvardsson, B., Enke, H., Eriksson, K., Esquej, P., Eynard Bontemps, G., Fabre, C., Fabrizio, M., Faigler, S., Falcão, A.J., Farràs Casas, M., Federici, L., Fedorets, G., Fernique, P., Figueras, F., Filippi, F., Findeisen, K., Fonti, A., Fraile, E., Fraser, M., Frézouls, B., Gai, M., Galleti, S., Garabato, D., García-Sedano, F., Garofalo, A., Garralda, N., Gavel, A., Gavras, P., Gerssen, J., Geyer, R., Giacobbe, P., Gilmore, G., Giuffrida, G., Girona, S., Glass, F., Gomes, M., Granvik, M., Gueguen, A., Guerrier, A., Guiraud, J., Gutiérrez-Sánchez, R., Hofmann, W., Holland, G., Huckle, H.E., Hypki, A., Icardi, V., Janßen, K., Jevardat De Fombelle, G., Jonker, P.G., Juhász, A.L., Julbe, F., Karampelas, A., Kewley, A., Klar, J., Kochoska, A., Kohley, R., Kolenberg, K., Kontizas, M., Kontizas, E., Koposov, S.E., Kordopatis, G., Kostrzewa-Rutkowska, Z., Koubsky, P., Lambert, S., Lanza, A.F., Lasne, Y., Lavigne, J.-B., Le Fustec, Y., Le Poncin-Lafitte, C., Lebreton, Y., Leccia, S., Leclerc, N., Lecoeur-Taibi, I., Lenhardt, H., Leroux, F., Liao, S., Licata, E., Lindstrøm, H.E.P., Lister, T.A., Livanou, E., Lobel, A., López, M., Managau, S., Mann, R.G., Mantelet, G., Marchal, O., Marchant, J.M., Marconi, M., Marinoni, S., Marschalkó, G., Marshall, D.J., Martino, M., Marton, G., Mary, N., Matijevic, G., Mazeh, T., Messina, S., Michalik, D., Millar, N.R., Molina, D., Molinaro, R., Molnár, L., Montegriffo, P., Mor, R., Morbidelli, R., Morel, T., Morris, D., Mulone, A.F., Muraveva, T., Musella, I., Nelemans, G., Nicastro, L., Noval, L., O'Mullane, W., Ordénovic, C., Ordóñez-Blanco, D., Osborne, P., Pagani, C., Pagano, I., Pailler, F., Palacin, H., Palaversa, L., Panahi, A., Pawlak, M., Piersimoni, A.M., Pineau, F.-X., Plachy, E., Plum, G., Poggio, E., Poujoulet, E., Prša, A., Pulone, L., Racero, E., Ragaini, S., Rambaux, N., Ramos-Lerate, M., Regibo, S., Riclet, F., Ripepi, V., Riva, A., Rivard, A., Rixon, G., Roegiers, T., Roelens, M., Romero-Gómez, M., Rowell, N., Royer, F., Ruiz-Dern, L., Sadowski, G., Sagristà Sellés, T., Sahlmann, J., Salgado, J., Salguero, E., Sanna, N., Santana-Ros, T., Sarasso, M., Savietto, H., Schultheis, M., Sciacca, E., Segol, M., Ségransan, D., Segovia, J.C., Shih, I-C., Siltala, L., Silva, A.F., Smart, R.L., Smith, K.W., Solano, E., Solitro, F., Sordo, R., Soria Nieto, S., Souchay, J., Spagna, A., Spoto, F., Stampa, U., Steele, I.A., Steidelmöller, H., Stephenson, C.A., Stoev, H., Suess, F.F., Surdej, J., Szabados, L., Szegedi-Elek, E., Tapiador, D., Taris, F., Tauran, G., Taylor, M.B., Teixeira, R., Terrett, D., Teyssandier, P., Thuillot, W., Titarenko, A., Torra Clotet, F., Turon, C., Ulla, A., Utrilla, E., Uzzi, S., Vaillant, M., Valentini, G., Valette, V., Van Elteren, A., Van Hemelryck, E., Van Leeuwen, M., Vaschetto, M., Vecchiato, A., Viala, Y., Vicente, D., Vogt, S., Von Essen, C., Voss, H., Votruba, V., Voutsinas, S., Walmsley, G., Weiler, M., Wertz, O., Wevems, T., Wyrzykowski, L., Yoldas, A., Žerjal, M., Ziaeepour, H., Zorec, J., Zschocke, S., Zucker, S., Zurbach, C., Zwitter, T., Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire national de métrologie et d'essais - Systèmes de Référence Temps-Espace (LNE - SYRTE), Systèmes de Référence Temps Espace (SYRTE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Univers et Particules de Montpellier (LUPM), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), FORMATION STELLAIRE 2018, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), M2A 2018, Institut de Physique de Rennes (IPR), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Department of Physics, Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), and Universitat de Barcelona
Subjects: Galaxy: kinematics and dynamics / astrometry / globular clusters: general / galaxies: dwarf / Local Group / Magellanic Clouds, dwarf [galaxies], Astronomy, Magellanic Cloud, PROPER MOTIONS, Globular clusters: general, Astrophysics, 01 natural sciences, Catàlegs d'estels, Star catalogs, TO-LIGHT RATIOS, Magellanic Clouds, VELOCITY DISPERSION PROFILE, Large Magellanic Cloud, 010303 astronomy & astrophysics, Galaxy rotation curve, general [globular clusters], Physics, Clusters of galaxies, Galaxies: dwarf, 520 Astronomy, Astrometry, galaxies: dwarf, Local Group, methods: data analysis, astrometry, SPACE VELOCITIES, astrometry, Astrophysics::Earth and Planetary Astrophysics, Galaxy: kinematics and dynamics, GALACTIC HALO, Cúmuls de galàxies, Local Group, Astrometria, EXPLORING HALO SUBSTRUCTURE, Milky Way, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Galaxy: halo, Magellanic Clouds, Settore FIS/05 - Astronomia e Astrofisica, SATELLITE GALAXIES, 0103 physical sciences, DARK-MATTER, globular clusters: general, galaxies: dwarf, Astrophysique, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Orbital elements, 010308 nuclear & particles physics, Astronomy and Astrophysics, Astronomie, Astronomy and Astrophysic, kinematics and dynamics [Galaxy], Galaxies, 115 Astronomy, Space science, Astrophysics - Astrophysics of Galaxies, Galaxy, Galàxies, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Stars, SPHEROIDAL GALAXY, Space and Planetary Science, Globular cluster, Astrophysics of Galaxies (astro-ph.GA), Galaxy: kinematics and dynamic, LARGE-MAGELLANIC-CLOUD
Abstract: Aims. The goal of this paper is to demonstrate the outstanding quality of the second data release of the Gaia mission and its power for constraining many di erent aspects of the dynamics of the satellites of the Milky Way. We focus here on determining the proper motions of 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, and the Large and Small Magellanic Clouds. Methods. Using data extracted from the Gaia archive, we derived the proper motions and parallaxes for these systems, as well as their uncertainties. We demonstrate that the errors, statistical and systematic, are relatively well understood. We integrated the orbits of these objects in three different Galactic potentials, and characterised their properties. We present the derived proper motions, space velocities, and characteristic orbital parameters in various tables to facilitate their use by the astronomical community. Results. Our limited and straightforward analyses have allowed us for example to (i) determine absolute and very precise proper motions for globular clusters; (ii) detect clear rotation signatures in the proper motions of at least five globular clusters; (iii) show that the satellites of the MilkyWay are all on high-inclination orbits, but that they do not share a single plane of motion; (iv) derive a lower limit for the mass of the Milky Way of 9:8$^{+6:7}_{2:7}$ x 10$6{11}$$\odot$ based on the assumption that the Leo I dwarf spheroidal is bound; (v) derive a rotation curve for the Large Magellanic Cloud based solely on proper motions that is competitive with line-of-sight velocity curves, now using many orders of magnitude more sources; and (vi) unveil the dynamical effect of the bar on the motions of stars in the Large Magellanic Cloud. Conclusions. All these results highlight the incredible power of the Gaia astrometric mission, and in particular of its second data release., Includes STFC and ERC.
Published: 2018

5. The gaia -ESO survey: calibration strategy

Author: Pancino, E., Lardo, C., Altavilla, G., Marinoni, S., Ragaini, S., Cocozza, G., Bellazzini, M., Sabbi, E., Zoccali, M., Donati, P., Heiter, U., Koposov, S. E., Blomme, R., Morel, T., Símon-Díaz, S., Lobel, A., Soubiran, C., Montalban, J., Valentini, M., Casey, A. R., Blanco-Cuaresma, S., Jofré, P., Worley, C. C., Magrini, L., Hourihane, A., François, P., Feltzing, S., Gilmore, G., Randich, S., Asplund, M., Bonifacio, P., Drew, J. E., Jeffries, R. D., Micela, G., Vallenari, A., Alfaro, E. J., Allende Prieto, C., Babusiaux, C., Bensby, T., angela Bragaglia, Flaccomio, E., Hambly, N., Korn, A. J., Lanzafame, A. C., Smiljanic, R., Eck, S., Walton, N. A., Bayo, A., Carraro, G., Costado, M. T., Damiani, F., Edvardsson, B., Franciosini, E., Frasca, A., Lewis, J., Monaco, L., Morbidelli, L., Prisinzano, L., Sacco, G. G., Sbordone, L., Sousa, S. G., Zaggia, S., Koch, A., Ministero dell'Istruzione, dell'Università e della Ricerca, Knut and Alice Wallenberg Foundation, European Research Council, Swedish National Space Board, Belgian Science Policy Office, National Science Centre (Poland), European Science Foundation, Ministerio de Economía y Competitividad (España), Pancino E., Lardo C., Altavilla G., Marinoni S., Ragaini S., Cocozza G., Bellazzini M., Sabbi E., Zoccali M., Donati P., Heiter U., Koposov S.E., Blomme R., Morel T., Simon-Diaz S., Lobel A., Soubiran C., Montalban J., Valentini M., Casey A.R., Blanco-Cuaresma S., Jofre P., Worley C.C., Magrini L., Hourihane A., Francois P., Feltzing S., Gilmore G., Randich S., Asplund M., Bonifacio P., Drew J.E., Jeffries R.D., Micela G., Vallenari A., Alfaro E.J., Allende Prieto C., Babusiaux C., Bensby T., Bragaglia A., Flaccomio E., Hambly N., Korn A.J., Lanzafame A.C., Smiljanic R., Van Eck S., Walton N.A., Bayo A., Carraro G., Costado M.T., Damiani F., Edvardsson B., Franciosini E., Frasca A., Lewis J., Monaco L., Morbidelli L., Prisinzano L., Sacco G.G., Sbordone L., Sousa S.G., Zaggia S., Koch A., Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), Royal Observatory of Belgium [Brussels] (ROB), Science et Ingénierie des Matériaux et Procédés (SIMaP ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), M2A 2017, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leibniz-Institut für Astrophysik Potsdam (AIP), Focas Research Institute, Dublin Institute of Technology, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), School of Physics, Astronomy and Mathematics [Hatfield], University of Hertfordshire [Hatfield] (UH), INAF - Osservatorio Astronomico di Palermo (OAPa), Istituto Nazionale di Astrofisica (INAF), Economía Política y Hacienda Pública, Estadística Económica y Empresarial y Política Económica, Universidad de Castilla-La Mancha (UCLM), Department of Astronomy and Space Physics [Uppsala], Uppsala University, INAF - Osservatorio Astrofisico di Catania (OACT), Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles (ULB), University of Turin, Department of Physiology and Pharmacology, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome]-Réseau International des Instituts Pasteur (RIIP)-Institut Pasteur, Fondation Cenci Bolognetti - Istituto Pasteur Italia, Fondazione Cenci Bolognetti, Réseau International des Instituts Pasteur (RIIP), Pôle Gérontologie, and Centre Hospitalier Universitaire de Nice (CHU Nice)
Subjects: Stars: abundance, Milky Way, FOS: Physical sciences, Techniques: spectroscopic, Astrophysics, Parameter space, Surveys, 01 natural sciences, Spectral line, surveys, 0103 physical sciences, Calibration, Emission spectrum, Survey, 010303 astronomy & astrophysics, Galaxy: general, Solar and Stellar Astrophysics (astro-ph.SR), QC, general [Galaxy], QB, Physics, [PHYS]Physics [physics], Observational error, 010308 nuclear & particles physics, Techniques: radial velocitie, Stars: abundances, Astronomy and Astrophysics, Ranging, radial velocities [techniques], [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astrophysics - Astrophysics of Galaxies, abundances [stars], Stars, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Techniques: radial velocities, stars: abundances, techniques: spectroscopic, techniques: radial velocities, spectroscopic [techniques], [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: The Gaia-ESO survey (GES) is now in its fifth and last year of observations and has produced tens of thousands of high-quality spectra of stars in all Milky Way components. This paper presents the strategy behind the selection of astrophysical calibration targets, ensuring that all GES results on radial velocities, atmospheric parameters, and chemical abundance ratios will be both internally consistent and easily comparable with other literature results, especially from other large spectroscopic surveys and from Gaia. The calibration of GES is particularly delicate because of (i) the large space of parameters covered by its targets, ranging from dwarfs to giants, from O to M stars; these targets have a large wide of metallicities and also include fast rotators, emission line objects, and stars affected by veiling; (ii) the variety of observing setups, with different wavelength ranges and resolution; and (iii) the choice of analyzing the data with many different state-of-the-art methods, each stronger in a different region of the parameter space, which ensures a better understanding of systematic uncertainties. An overview of the GES calibration and homogenization strategy is also given, along with some examples of the usage and results of calibrators in GES iDR4, which is the fourth internal GES data release and will form the basis of the next GES public data release. The agreement between GES iDR4 recommended values and reference values for the calibrating objects are very satisfactory. The average offsets and spreads are generally compatible with the GES measurement errors, which in iDR4 data already meet the requirements set by the main GES scientific goals.© ESO, 2017., This work was partly supported by the European Union FP7 program through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR) in the form of the grant >Premiale VLT 2012>. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. S.F. and T.B. acknowledge the support from the New Milky Way project funded by a grant from the Knut and Alice Wallenberg foundation. C.L. gratefully acknowledges financial support from the European Research Council (ERC-CoG-646928, Multi-Pop, PI: N. Bastian). U.H. and A.J.K acknowledge support from the Swedish National Space Board (Rymdstyrelsen). The research of A.L. has been subsidized by the Belgian Federal Science Policy Office under contract No. BR/143/A2/BRASS. R.S. acknowledges support by the National Science Center of Poland through grant 2014/15/B/ST9/03981. C.A.P. is thankful for support from the Spanish Ministry of Economy and Competitiveness (MINECO) through grant AYA2014-56359-P.J.M. acknowledges support from the ERC Consolidator Grant funding scheme (project STARKEY, G.A. No. 615604). T.M. acknowledges financial support from Belspo for contract PRODEX Gaia-DPAC. S.G.S acknowledges the support by Fundacao para a Ciencia e Tecnologia (FCT) through national funds and a research grant (project ref. UID/FIS/04434/2013, and PTDC/FIS-AST/7073/2014). S.G.S. also acknowledge the support from FCT through Investigador FCT contract of reference IF/00028/2014 and POPH/FSE (EC) by FEDER funding through the program >Programa Operacional de Factores de Competitividade - COMPETE>. L.S. acknowledges support by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics (MAS). M.Z. acknowledges support by the Ministry of Economy, Development, and Tourism's Millennium Science Initiative through grant IC120009, awarded to The Millennium Institute of Astrophysics (MAS), by Fondecyt Regular 1150345 and by the BASAL CATA PFB-06. E.J.A. and M.T.C acknowledge the financial support from the Spanish Ministerio de Economia y Competitividad, through grant AYA2013-40611-P.S.Z. acknowledge the support from the INAF grant >PRIN INAF 2014>, >Star won't tell their ages to Gaia, Galactic Archaelogy with wide-area asterosismic>.
Published: 2017

6. Gaia Data Release 2 Mapping the Milky Way disc kinematics

Author: Katz, D., Antoja, T., Romero-Gomez, M., Drimmel, R., Reyle, C., Seabroke, G. M., Soubiran, C., Babusiaux, C., Di Matteo, P., Figueras, F., Poggio, E., Robin, A. C., Evans, D. W., Brown, A. G. A., Vallenari, A., Prusti, T., de Bruijne, J. H. J., Bailer-Jones, C. A. L., Biermann, M., Eyer, L., Jansen, F., Jordi, C., Klioner, S. A., Lammers, U., Lindegren, L., Luri, X., Mignard, F., Panem, C., Pourbaix, D., Randich, S., Sartoretti, P., Siddiqui, H. I., van Leeuwen, F., Walton, N. A., Arenou, F., Bastian, U., Cropper, M., Lattanzi, M. G., Bakker, J., Cacciari, C., Castaneda, J., Chaoul, L., Cheek, N., De Angeli, F., Fabricius, C., Guerra, R., Holl, B., Masana, E., Messineo, R., Mowlavi, N., Nienartowicz, K., Panuzzo, P., Portell, J., Riello, M., Tanga, P., Thevenin, F., Gracia-Abril, G., Comoretto, G., Garcia-Reinaldos, M., Teyssier, D., Altmann, M., Andrae, R., Audard, M., Bellas-Velidis, I., Benson, K., Berthier, J., Blomme, R., Burgess, P., Busso, G., Carry, B., Cellino, A., Clementini, G., Clotet, M., Creevey, O., Davidson, M., De Ridder, J., Delchambre, L., Dell'Oro, A., Ducourant, C., Fernandez-Hernandez, J., Fouesneau, M., Fremat, Y., Galluccio, L., Garcia-Torres, M., Gonzalez-Nunez, J., Gonzalez-Vidal, J. J., Gosset, E., Guy, L. P., Halbwachs, J. -L., Hambly, N. C., Harrison, D. L., Hernandez, J., Hestroffer, D., Hodgkin, S. T., Hutton, A., Jasniewicz, G., Jean-Antoine-Piccolo, A., Jordan, S., Korn, A. J., Krone-Martins, A., Lanzafame, A. C., Lebzelter, T., Loeffler, W., Manteiga, M., Marrese, P. M., Martin-Fleitas, J. M., Moitinho, A., Mora, A., Muinonen, K., Osinde, J., Pancino, E., Pauwels, T., Petit, J. -M., Recio-Blanco, A., Richards, P. J., Rimoldini, L., Sarro, L. M., Siopis, C., Smith, M., Sozzetti, A., Sueveges, M., Torra, J., van Reeven, W., Abbas, U., Abreu Aramburu, A., Accart, S., Aerts, C., Altavilla, G., Alvarez, M. A., Alvarez, R., Alves, J., Anderson, R. I., Andrei, A. H., Anglada Varela, E., Antiche, E., Arcay, B., Astraatmadja, T. L., Bach, N., Baker, S. G., Balaguer-Nunez, L., Balm, P., Barache, C., Barata, C., Barbato, D., Barblan, F., Barklem, P. S., Barrado, D., Barros, M., Barstow, M. A., Bartholome Munoz, S., Bassilana, J. -L., Becciani, U., Bellazzini, M., Berihuete, A., Bertone, S., Bianchi, L., Bienayme, O., Blanco-Cuaresma, S., Boch, T., Boeche, C., Bombrun, A., Borrachero, R., Bossini, D., Bouquillon, S., Bourda, G., Bragaglia, A., Bramante, L., Breddels, M. A., Bressan, A., Brouillet, N., Bruesemeister, T., Brugaletta, E., Bucciarelli, B., Burlacu, A., Busonero, D., Butkevich, A. G., Buzzi, R., Caffau, E., Cancelliere, R., Cannizzaro, G., Cantat-Gaudin, T., Carballo, R., Carlucci, T., Carrasco, J. M., Casamiquela, L., Castellani, M., Castro-Ginard, A., Charlot, P., Chemin, L., Chiavassa, A., Cocozza, G., Costigan, G., Cowell, S., Crifo, F., Crosta, M., Crowley, C., Cuypers, J., Dafonte, C., Damerdji, Y., Dapergolas, A., David, P., David, M., de Laverny, P., De Luise, F., De March, R., de Souza, R., de Torres, A., Debosscher, J., del Pozo, E., Delbo, M., Delgado, A., Delgado, H. E., Diakite, S., Diener, C., Distefano, E., Dolding, C., Drazinos, P., Duran, J., Edvardsson, B., Enke, H., Eriksson, K., Esquej, P., Bontemps, G. Eynard, Fabre, C., Fabrizio, M., Faigler, S., Falcao, A. J., Farras Casas, M., Federici, L., Fedorets, G., Fernique, P., Filippi, F., Findeisen, K., Fonti, A., Fraile, E., Fraser, M., Frezouls, B., Gai, M., Galleti, S., Garabato, D., Garcia-Sedano, F., Garofalo, A., Garralda, N., Gavel, A., Gavras, P., Gerssen, J., Geyer, R., Giacobbe, P., Gilmore, G., Girona, S., Giuffrida, G., Glass, F., Gomes, M., Granvik, M., Gueguen, A., Guerrier, A., Guiraud, J., Gutierrez-Sanchez, R., Haigron, R., Hatzidimitriou, D., Hauser, M., Haywood, M., Heiter, U., Helmi, A., Heu, J., Hilger, T., Hobbs, D., Hofmann, W., Holland, G., Huckle, H. E., Hypki, A., Icardi, V., Janssen, K., de Fombelle, G. Jevardat, Jonker, P. G., Juhasz, A. L., Julbe, F., Karampelas, A., Kewley, A., Klar, J., Kochoska, A., Kohley, R., Kolenberg, K., Kontizas, M., Kontizas, E., Koposov, S. E., Kordopatis, G., Kostrzewa-Rutkowska, Z., Koubsky, P., Lambert, S., Lanza, A. F., Lasne, Y., Lavigne, J. -B., Le Fustec, Y., Le Poncin-Lafitte, C., Lebreton, Y., Leccia, S., Leclerc, N., Lecoeur-Taibi, I., Lenhardt, H., Leroux, F., Liao, S., Licata, E., Lindstrom, H. E. P., Lister, T. A., Livanou, E., Lobel, A., Lopez, M., Managau, S., Mann, R. G., Mantelet, G., Marchal, O., Marchant, J. M., Marconi, M., Marinoni, S., Marschalko, G., Marshall, D. J., Martino, M., Marton, G., Mary, N., Massari, D., Matijevic, G., Mazeh, T., McMillan, P. J., Messina, S., Michalik, D., Millar, N. R., Molina, D., Molinaro, R., Molnar, L., Montegriffo, P., Mor, R., Morbidelli, R., Morel, T., Morris, D., Mulone, A. F., Muraveva, T., Musella, I., Nelemans, G., Nicastro, L., Noval, L., O'Mullane, W., Ordenovic, C., Ordonez-Blanco, D., Osborne, P., Pagani, C., Pagano, I., Pailler, F., Palacin, H., Palaversa, L., Panahi, A., Pawlak, M., Piersimoni, A. M., Pineau, F. -X., Plachy, E., Plum, G., Poujoulet, E., Prsa, A., Pulone, L., Racero, E., Ragaini, S., Rambaux, N., Ramos-Lerate, M., Regibo, S., Riclet, F., Ripepi, V., Riva, A., Rivard, A., Rixon, G., Roegiers, T., Roelens, M., Rowell, N., Royer, F., Ruiz-Dern, L., Sadowski, G., Selles, T. Sagrista, Sahlmann, J., Salgado, J., Salguero, E., Sanna, N., Santana-Ros, T., Sarasso, M., Savietto, H., Schultheis, M., Sciacca, E., Segol, M., Segovia, J. C., Segransan, D., Shih, I-C., Siltala, L., Silva, A. F., Smart, R. L., Smith, K. W., Solano, E., Solitro, F., Sordo, R., Soria Nieto, S., Souchay, J., Spagna, A., Spoto, F., Stampa, U., Steele, I. A., Steidelmueller, H., Stephenson, C. A., Stoev, H., Suess, F. F., Surdej, J., Szabados, L., Szegedi-Elek, E., Tapiador, D., Taris, F., Tauran, G., Taylor, M. B., Teixeira, R., Terrett, D., Teyssandier, P., Thuillot, W., Titarenko, A., Torra Clotet, F., Turon, C., Ulla, A., Utrilla, E., Uzzi, S., Vaillant, M., Valentini, G., Valette, V., van Elteren, A., Van Hemelryck, E., van Leeuwen, M., Vaschetto, M., Vecchiato, A., Veljanoski, J., Viala, Y., Vicente, D., Vogt, S., von Essen, C., Voss, H., Votruba, V., Voutsinas, S., Walmsley, G., Weiler, M., Wertz, O., Wevers, T., Wyrzykowski, L., Yoldas, A., Zerjal, M., Ziaeepour, H., Zorec, J., Zschocke, S., Zucker, S., Zurbach, C., Zwitter, T., Collaboration, Gaia, Kapteyn Astronomical Institute, Astronomy, Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Planétologie et d'Astrophysique de Grenoble (IPAG), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG ), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Agence Spatiale Européenne (ESA), European Space Agency (ESA), Geneva Observatory, University of Geneva [Switzerland], Institut de Ciencies del Cosmos (ICCUB), Universitat de Barcelona (UB), Institut de Ciènces del Cosmos (ICC), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES), Université libre de Bruxelles (ULB), Zentrum für astronomie, Universität Heidelberg [Heidelberg], International Center for Relativistic Astrophysics (ICRA), Università degli Studi di Roma, Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), University of Las Palmas de Gran Canaria (ULPGC), Departament de Geodinamica i Geofısica, Facultat de Geologia, European Space Astronomy Centre (ESAC), Systèmes de Référence Temps Espace (SYRTE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Université de Genève (UNIGE), Department of Physics and Astronomy [UCL London], University College of London [London] (UCL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Royal Observatory of Belgium [Brussels] (ROB), Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astrofisico di Torino (OATo), Istituto Nazionale di Astrofisica (INAF), Alma Mater Studiorum Università di Bologna [Bologna] (UNIBO), Open University of Israël, Instituut voor Sterrenkunde [Leuven], Catholic University of Leuven - Katholieke Universiteit Leuven (KU Leuven), Laboratoire d'astrophysique de l'observatoire de Besançon (UMR 6091) (LAOB), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Centre National de la Recherche Scientifique (CNRS)-Université de Lille-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy and Space Physics [Uppsala], Uppsala University, SIM/IDL Faculdade de Ciências da Universidade de Lisboa (FCUL), University of Lisboa, Universidad de Granada (UGR), Helsinki Institute of Physics (HIP), University of Helsinki, INAF - Osservatorio Astronomico di Bologna (OABO), Département d'Astrophysique, de physique des Particules, de physique Nucléaire et de l'Instrumentation Associée (DAPNIA), United States Geological Survey [Reston] (USGS), National Institute for Subatomic Physics [Amsterdam] (NIKHEF), Department of Medicine, Icahn School of Medicine at Mount Sinai [New York] (MSSM), Department of Physics and Astronomy [Uppsala], Centro de Astrobiologia [Madrid] (CAB), Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Madrid] (CSIC), Department of Physics and Astronomy [Leicester], University of Leicester, Observatoire astronomique de Strasbourg (OAS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Louis Pasteur - Strasbourg I-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Roma (OAR), Institute of Astronomy [Leuven], Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Astrometry, Istituto Nazionale di Astrofisica (INAF)-Istituto Nazionale di Astrofisica (INAF), Universidade de Lisboa (ULISBOA), Department of Physics [Athens], National and Kapodistrian University of Athens (NKUA), Laboratoire national de métrologie et d'essais - Systèmes de Référence Temps-Espace (LNE - SYRTE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), INAF - Osservatorio Astronomico di Capodimonte (OAC), Laboratoire d'Ingienerie des Polymères pour les Hautes Technologies (LIPHT), Ecole européenne de chimie, polymères et matériaux [Strasbourg]-Centre National de la Recherche Scientifique (CNRS), TKK Helsinki University of Technology (TKK), School of Physics and Astronomy [Tel Aviv], Tel Aviv University [Tel Aviv], Institut Supérieur de l'Aéronautique et de l'Espace (ISAE-SUPAERO), INAF - Osservatorio Astrofisico di Catania (OACT), Inst. Ciencia Molecular, Universitat de València (UV), Astronomical Observatory [Poznan], Adam Mickiewicz University in Poznań (UAM), Observatoire Astronomique de l'Université de Genève (ObsGE), Spanish Virtual Observatory - Observatorio Virtual Español (SVO), Spanish Virtual Observatory - Observatorio Virtual Español, Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Konkoly Observatory, Research Centre for Astronomy and Earth Sciences [Budapest], Hungarian Academy of Sciences (MTA)-Hungarian Academy of Sciences (MTA), Instituto de Astronomia, Geofísica e Ciências Atmosféricas [São Paulo] (IAG), Universidade de São Paulo (USP), Department of Astrophysics [Nijmegen], Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen]-Radboud university [Nijmegen], Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Lohrmann Observatory, Technische Universität Dresden = Dresden University of Technology (TU Dresden), Universitat de Barcelona, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Agence Spatiale Européenne = European Space Agency (ESA), Université de Genève = University of Geneva (UNIGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Universität Heidelberg [Heidelberg] = Heidelberg University, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Universidad de Granada = University of Granada (UGR), Helsingin yliopisto = Helsingfors universitet = University of Helsinki, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), Universidade de Lisboa = University of Lisbon (ULISBOA), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Tel Aviv] (TAU), Raymond and Beverly Sackler Faculty of Exact Sciences [Tel Aviv] (TAU), Tel Aviv University (TAU)-Tel Aviv University (TAU), Universidade de São Paulo = University of São Paulo (USP), Radboud University [Nijmegen]-Radboud University [Nijmegen], Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Consejo Superior de Investigaciones Científicas [Madrid] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Universidad de Cantabria, PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Centre National d'Études Spatiales [Toulouse] (CNES)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Libre de Bruxelles [Bruxelles] (ULB), Royal Observatory of Belgium [Brussels], PSL Research University (PSL)-PSL Research University (PSL)-Université de Lille-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Università di Bologna [Bologna] (UNIBO), Laboratoire d'astrophysique de l'observatoire de Besançon (LAOB), PSL Research University (PSL)-PSL Research University (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS), Université de Montpellier (UM)-Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Osservatorio Astronomico di Bologna (OABO), National Institute for Subatomic Physics Nikhef [Amsterdam] (NIKHEF), Consejo Superior de Investigaciones Científicas [Spain] (CSIC)-Instituto Nacional de Técnica Aeroespacial (INTA), Università degli Studi di Roma 'La Sapienza' [Rome], National and Kapodistrian University of Athens = University of Athens (NKUA | UoA), PSL Research University (PSL)-PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Instituto de Astronomia, Geofisica e Ciencias Atmosfericas [Sao Paulo] (IAG), Technische Universität Dresden (TUD), Department of Physics, Instituto Nacional de Técnica Aeroespacial (INTA)-Consejo Superior de Investigaciones Científicas [Spain] (CSIC), and Gaia Collaboration
Subjects: SOLAR NEIGHBORHOOD, SPECTROSCOPIC SURVEY, Astronomy, SAGITTARIUS DWARF GALAXY, GALACTIC WARP, Kinematics, Astrophysics, 01 natural sciences, Astronomi, astrofysik och kosmologi, Discs (Astrofísica), Astronomy, Astrophysics and Cosmology, 010303 astronomy & astrophysics, QC, QB, Physics, 520 Astronomy, GALÁXIAS, Radius, Radial velocity, Milky Way, Disks (Astrophysics), Galaxy: kinematics and dynamics - Galaxy: disk - solar neighborhood, Physical Sciences, MAGELLANIC STREAM, Vector field, Astrophysics::Earth and Planetary Astrophysics, Galaxy: kinematics and dynamics, disk [Galaxy], Galaxy: kinematics and dynamics – Galaxy: disk – solar neighborhood, LOCAL KINEMATICS, GALACTIC EVOLUTION EXPERIMENT, SPIRAL ARMS, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astronomy & Astrophysics, kinematics and dynamics - Galaxy: disk - solar neighborhood [Galaxy], Galaxy: disk, PHASE-SPACE STRUCTURE, Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, Astrophysique, Via Làctia, Astrophysics::Galaxy Astrophysics, Science & Technology, 010308 nuclear & particles physics, Plane (geometry), Solar neighborhood, Astronomy and Astrophysics, Space and Planetary Science, HERCULES STREAM, Astronomie, kinematics and dynamics [Galaxy], Giant star, 115 Astronomy, Space science, Galaxies, Astrophysics - Astrophysics of Galaxies, Galàxies, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Stars, GENEVA-COPENHAGEN SURVEY, STELLAR VELOCITY DISTRIBUTION, RED-CLUMP GIANTS, Astrophysics of Galaxies (astro-ph.GA), MINOR MERGERS, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: Context. The second Gaia data release (Gaia DR2) contains high-precision positions, parallaxes, and proper motions for 1.3 billion sources as well as line-of-sight velocities for 7.2 million stars brighter than GRVS = 12 mag. Both samples provide a full sky coverage. Aims. To illustrate the potential of Gaia DR2, we provide a first look at the kinematics of the Milky Way disc, within a radius of several kiloparsecs around the Sun. Methods. We benefit for the first time from a sample of 6.4 million F-G-K stars with full 6D phase-space coordinates, precise parallaxes (σω/ω/≤ 20%), and precise Galactic cylindrical velocities (median uncertainties of 0.9-1.4 km s-1 and 20% of the stars with uncertainties smaller than 1 km s-1 on all three components). From this sample, we extracted a sub-sample of 3.2 million giant stars to map the velocity field of the Galactic disc from ∼5 kpc to ∼13 kpc from the Galactic centre and up to 2 kpc above and below the plane. We also study the distribution of 0.3 million solar neighbourhood stars (r < 200 pc), with median velocity uncertainties of 0.4 km s-1, in velocity space and use the full sample to examine how the over-densities evolve in more distant regions. Results. Gaia DR2 allows us to draw 3D maps of the Galactocentric median velocities and velocity dispersions with unprecedented accuracy, precision, and spatial resolution. The maps show the complexity and richness of the velocity field of the galactic disc. We observe streaming motions in all the components of the velocities as well as patterns in the velocity dispersions. For example, we confirm the previously reported negative and positive galactocentric radial velocity gradients in the inner and outer disc, respectively. Here, we see them as part of a non-axisymmetric kinematic oscillation, and we map its azimuthal and vertical behaviour. We also witness a new global arrangement of stars in the velocity plane of the solar neighbourhood and in distant regions in which stars are organised in thin substructures with the shape of circular arches that are oriented approximately along the horizontal direction in the U - V plane. Moreover, in distant regions, we see variations in the velocity substructures more clearly than ever before, in particular, variations in the velocity of the Hercules stream. Conclusions. Gaia DR2 provides the largest existing full 6D phase-space coordinates catalogue. It also vastly increases the number of available distances and transverse velocities with respect to Gaia DR1. Gaia DR2 offers a great wealth of information on the Milky Way and reveals clear non-axisymmetric kinematic signatures within the Galactic disc, for instance. It is now up to the astronomical community to explore its full potential., 0, info:eu-repo/semantics/published
Published: 2018

7. The Gaia-ESO Survey: Spectroscopic-asteroseismic analysis of K2 stars in Gaia-ESO: The K2 Galactic Caps Project.

Author: Worley, C. C., Jofré, P., Rendle, B., Miglio, A., Magrini, L., Feuillet, D., Gavel, A., Smiljanic, R., Lind, K., Korn, A., Gilmore, G., Randich, S., Hourihane, A., Gonneau, A., Francois, P., Lewis, J., Sacco, G., Bragaglia, A., Heiter, U., and Feltzing, S.
Subjects: RED giants, STELLAR populations, ASTEROSEISMOLOGY, PARALLAX, STARS, MILKY Way
Abstract: Context. The extensive stellar spectroscopic datasets that are available for studies in Galactic Archeaology thanks to, for example, the Gaia-ESO Survey, now benefit from having a significant number of targets that overlap with asteroseismology projects such as Kepler, K2, and CoRoT. Combining the measurements from spectroscopy and asteroseismology allows us to attain greater accuracy with regard to the stellar parameters needed to characterise the stellar populations of the Milky Way. Aims. The aim of this Gaia-ESO Survey special project is to produce a catalogue of self-consistent stellar parameters by combining measurements from high-resolution spectroscopy and precision asteroseismology. Methods. We carried out an iterative analysis of 90 K2@Gaia-ESO red giants. The spectroscopic values of Teff were used as input in the seismic analysis to obtain log g values. The seismic estimates of log g were then used to re-determine the spectroscopic values of Teff and [Fe/H]. Only one iteration was required to obtain parameters that are in good agreement for both methods and, thus, to obtain the final stellar parameters. A detailed analysis of outliers was carried out to ensure a robust determination of the parameters. The results were then combined with Gaia DR2 data to compare the seismic log g with a parallax-based log g and to investigate instances of variations in the velocity and possible binaries within the dataset. Results. This analysis produced a high-quality catalogue of stellar parameters for 90 red giant stars from K2@Gaia-ESO that were determined through iterations between spectroscopy and asteroseismology. We compared the seismic gravities with those based on Gaia parallaxes to find an offset which is similar to other studies that have used asteroseismology. Our catalogue also includes spectroscopic chemical abundances and radial velocities, as well as indicators for possible binary detections. [ABSTRACT FROM AUTHOR]
Published: 2020
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8. The Gaia-ESO Survey: membership probabilities for stars in 32 open clusters from 3D kinematics.

Author: Jackson, R J, Jeffries, R D, Wright, N J, Randich, S, Sacco, G, Pancino, E, Cantat-Gaudin, T, Gilmore, G, Vallenari, A, Bensby, T, Bayo, A, Costado, M T, Franciosini, E, Gonneau, A, Hourihane, A, Lewis, J, Monaco, L, Morbidelli, L, and Worley, C
Subjects: OPEN clusters of stars, KINEMATICS, PROBABILITY theory, PARALLAX, ASTROMETRY, MILKY Way
Abstract: The Gaia -ESO Survey (GES) observed many open clusters as part of its programme to spectroscopically characterize the various Milky Way populations. GES spectroscopy and Gaia astrometry from its second data release are used here to assign membership probabilities to targets towards 32 open clusters with ages from 1 to 3800 Myr, based on maximum likelihood modelling of the 3D kinematics of the cluster and field populations. From a parent catalogue of 14 398 individual targets, 5032 stars with uniformly determined 3D velocities, T eff, log g , and chemistry are assigned cluster membership with probability >0.9, and with an average probability of 0.991. The robustness of the membership probabilities is demonstrated using independent membership criteria (lithium and parallax) in two of the youngest clusters. The addition of radial velocities improves membership discrimination over proper motion selection alone, especially in more distant clusters. The kinematically selected nature of the membership lists, independent of photometry and chemistry, makes the catalogue a valuable resource for testing stellar evolutionary models and investigating the time evolution of various parameters. [ABSTRACT FROM AUTHOR]
Published: 2020
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9. VizieR Online Data Catalog: RAVE 4th data release (Kordopatis+, 2013)

Author: Kordopatis, G., Gilmore, G., Steinmetz, M., Boeche, C., Seabroke, G. M., Siebert, A., Zwitter, T., Binney, J., de Laverny, P., Recio-Blanco, A., Williams, M. E. K., Piffl, T., Enke, H., Roeser, S., Bijaoui, A., Wyse, R. F. G., Freeman, K., Munari, U., Carrillo, I., Anguiano, B., Burton, D., Campbell, R., Cass, C. J. P., Fiegert, K., Hartley, M., Parker, Q. A., Reid, W., Ritter, A., Russell, K. S., Stupar, M., Watson, F. G., Bienayme, O., Bland-Hawthorn, J., Gerhard, O., Gibson, B. K., Grebel, E. K., Helmi, A., Navarro, J. F., Conrad, C., Famaey, B., Faure, C., Just, A., Kos, J., Matijevic, G., McMillan, P. J., Minchev, I., Scholz, R., Sharma, S., Siviero, A., Wylie de Boer, E., Zerjal, M., Astronomy, and Physics of Nanodevices
Subjects: Milky Way, Photometry, Radial velocities, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, Stars: fundamental, Astrophysics::Galaxy Astrophysics, Physics::Geophysics
Abstract: Spectroscopic radial velocities for 425,561 stars in the Milky-Way southern hemisphere using the 6dF instrument at the AAO. Targets new to this release are drawn from a new input catalog based on the I magnitude from the DENIS point source catalog. The spectroscopic observations are made in the Calcium triplet region at a resolution of ~7,500. (1 data file).
Published: 2014

10. Is the Milky Way still breathing? RAVE-Gaia streaming motions.

Author: Carrillo, I., Minchev, I., Kordopatis, G., Steinmetz, M., Binney, J., Anders, F., Bienaymé, O., Bland-Hawthorn, J., Famaey, B., Freeman, K. C., Gilmore, G., Gibson, B. K., Grebel, E. K., Helmi, A., Just, A., Kunder, A., McMillan, P., Monari, G., Munari, U., and Navarro, J.
Subjects: RADIAL velocity of stars, ASTROMETRY, GALACTIC dynamics, DISKS (Astrophysics), MILKY Way
Abstract: We use data from the Radial Velocity Experiment (RAVE) and the Tycho-Gaia astrometric solution (TGAS) catalogue to compute the velocity fields yielded by the radial (VR), azimuthal (Vϕ),and vertical (Vz) components of associated Galactocentric velocity.We search in particular for variation in all three velocity components with distance above and below the disc midplane, as well as how each component of Vz (line-of-sight and tangential velocity projections) modifies the obtained vertical structure. To study the dependence of velocity on proper motion and distance, we use two main samples: a RAVE sample including proper motions from the Tycho-2, PPMXL, and UCAC4 catalogues, and a RAVE-TGAS sample with inferred distances and proper motions from the TGAS and UCAC5 catalogues. In both samples, we identify asymmetries in VR and Vz. Below the plane, we find the largest radial gradient to be ∂VR/∂R = -7.01 ± 0.61 km s-1 kpc-1, in agreement with recent studies. Above the plane, we find a similar gradient with ∂VR/∂R = -9.42 ± 1.77 km s-1 kpc-1. By comparing our results with previous studies, we find that the structure in Vz is strongly dependent on the adopted proper motions. Using the Galaxia Milky Way model, we demonstrate that distance uncertainties can create artificial wave-like patterns. In contrast to previous suggestions of a breathing mode seen in RAVE data, our results support a combination of bending and breathing modes, likely generated by a combination of external or internal and external mechanisms. [ABSTRACT FROM AUTHOR]
Published: 2018
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11. The Gaia-ESO Survey: Churning through the Milky Way.

Author: Hayden, M. R., Recio-Blanco, A., de Laverny, P., Mikolaitis, S., Guiglion, G., Hill, V., Gilmore, G., Randich, S., Bayo, A., Bensby, T., Bergemann, M., Bragaglia, A., Casey, A., Costado, M., Feltzing, S., Franciosini, E., Hourihane, A., Jofre, P., Koposov, S., and Kordopatis, G.
Subjects: ASTRONOMICAL observations, GALACTIC evolution, MILKY Way, STELLAR orbits, STELLAR populations, GALACTIC dynamics, KINEMATICS
Abstract: Context. There have been conflicting results with respect to the extent that radial migration has played in the evolution of the Galaxy. Additionally, observations of the solar neighborhood have shown evidence of a merger in the past history of the Milky Way that drives enhanced radial migration. Aims. We attempt to determine the relative fraction of stars that have undergone significant radial migration by studying the orbital properties of metal-rich ([Fe/H] > 0.1) stars within 2 kpc of the Sun. We also aim to investigate the kinematic properties, such as velocity dispersion and orbital parameters, of stellar populations near the Sun as a function of [Mg/Fe] and [Fe/H], which could show evidence of a major merger in the past history of the Milky Way. Methods. We used a sample of more than 3000 stars selected from the fourth internal data release of the Gaia-ESO Survey. We used the stellar parameters from the Gaia-ESO Survey along with proper motions from PPMXL to determine distances, kinematics, and orbital properties for these stars to analyze the chemodynamic properties of stellar populations near the Sun. Results. Analyzing the kinematics of the most metal-rich stars ([Fe/H] > 0.1), we find that more than half have small eccentricities (e< 0.2) or are on nearly circular orbits. Slightly more than 20% of the metal-rich stars have perigalacticons Rp> 7 kpc. We find that the highest [Mg/Fe], metal-poor populations have lower vertical and radial velocity dispersions compared to lower [Mg/Fe] populations of similar metallicity by ~10 km s-1. The median eccentricity increases linearly with [Mg/Fe] across all metallicities, while the perigalacticon decreases with increasing [Mg/Fe] for all metallicities. Finally, the most [Mg/Fe]-rich stars are found to have significant asymmetric drift and rotate more than 40 km s-1 slower than stars with lower [Mg/Fe] ratios. Conclusions. While our results cannot constrain how far stars have migrated, we propose that migration processes are likely to have played an important role in the evolution of the Milky Way, with metal-rich stars migrating from the inner disk toward to solar neighborhood and past mergers potentially driving enhanced migration of older stellar populations in the disk. [ABSTRACT FROM AUTHOR]
Published: 2018
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12. The Gaia-ESO Survey: matching chemodynamical simulations to observations of the Milky Way.

Author: Thompson, B. B., Few, C. G., Bergemann, M., Gibson, B. K., MacFarlane, B. A., Serenelli, A., Gilmore, G., Randich, S., Vallenari, A., Alfaro, E. J., Bensby, T., Francois, P., Korn, A. J., Bayo, A., Carraro, G., Casey, A. R., Costado, M. T., Donati, P., Franciosini, E., and Frasca, A.
Subjects: MILKY Way, GALAXIES, ASTRONOMICAL photometry, ATMOSPHERIC temperature, SIMULATION methods & models
Abstract: The typical methodology for comparing simulated galaxies with observational surveys is usually to apply a spatial selection to the simulation to mimic the region of interest covered by a comparable observational survey sample. In this work, we compare this approach with a more sophisticated post-processing in which the observational uncertainties and selection effects (photometric, surface gravity and effective temperature) are taken into account. We compare a 'solar neighbourhood analogue' region in a model MilkyWay-like galaxy simulated with RAMSES-CH with fourth release Gaia-ESO survey data. We find that a simple spatial cut alone is insufficient and that the observational uncertainties must be accounted for in the comparison. This is particularly true when the scale of uncertainty is large compared to the dynamic range of the data, e.g. in our comparison, the [Mg/Fe] distribution is affected much more than the more accurately determined [Fe/H] distribution. Despite clear differences in the underlying distributions of elemental abundances between simulation and observation, incorporating scatter to our simulation results to mimic observational uncertainty produces reasonable agreement. The quite complete nature of the Gaia-ESO survey means that the selection function has minimal impact on the distribution of observed age and metal abundances but this would become increasingly more important for surveys with narrower selection functions. [ABSTRACT FROM AUTHOR]
Published: 2018
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13. PLATO as it is: A legacy mission for Galactic archaeology.

Author: Miglio, A., Chiappini, C., Mosser, B., Davies, G. R., Freeman, K., Girardi, L., Jofré, P., Kawata, D., Rendle, B. M., Valentini, M., Casagrande, L., Chaplin, W. J., Gilmore, G., Hawkins, K., Holl, B., Appourchaux, T., Belkacem, K., Bossini, D., Brogaard, K., and Goupil, M.‐J.
Subjects: SEISMOLOGY, ASTRONOMICAL photometry, SPECTRUM analysis, RED giants, GALACTIC evolution, MILKY Way
Abstract: Deciphering the assembly history of the Milky Way is a formidable task, which becomes possible only if one can produce high-resolution chrono-chemo-kinematical maps of the Galaxy. Data from large-scale astrometric and spectroscopic surveys will soon provide us with a well-defined view of the current chemo-kinematical structure of the Milky Way, but it will only enable a blurred view on the temporal sequence that led to the present-day Galaxy. As demonstrated by the (ongoing) exploitation of data from the pioneering photometric missions CoRoT, Kepler, and K2, asteroseismology provides the way forward: solar-like oscillating giants are excellent evolutionary clocks thanks to the availability of seismic constraints on their mass and to the tight age-initial mass relation they adhere to. In this paper we identify five key outstanding questions relating to the formation and evolution of the Milky Way that will need precise and accurate ages for large samples of stars to be addressed, and we identify the requirements in terms of number of targets and the precision on the stellar properties that are needed to tackle such questions. By quantifying the asteroseismic yields expected from PLATO for red giant stars, we demonstrate that these requirements are within the capabilities of the current instrument design, provided that observations are sufficiently long to identify the evolutionary state and allow robust and precise determination of acoustic-mode frequencies. This will allow us to harvest data of sufficient quality to reach a 10% precision in age. This is a fundamental prerequisite to then reach the more ambitious goal of a similar level of accuracy, which will be possible only if we have at hand a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics, a goal that conveniently falls within the main aims of PLATO's core science. We therefore strongly endorse PLATO's current design and proposed observational strategy, and conclude that PLATO, as it is, will be a legacy mission for Galactic archaeology. [ABSTRACT FROM AUTHOR]
Published: 2017
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14. Gaia FGK benchmark stars: opening the black box of stellar element abundance determination.

Author: Jofré, P., Heiter, U., Worley, C. C., Blanco-Cuaresma, S., Soubiran, C., Masseron, T., Hawkins, K., Adibekyan, V., Buder, S., Casamiquela, L., Gilmore, G., Hourihane, A., and Tabernero, H.
Subjects: STELLAR evolution, COSMIC abundances, STELLAR spectra, STAR formation, MILKY Way
Abstract: Gaia and its complementary spectroscopic surveys combined will yield the most comprehensive database of kinematic and chemical information of stars in the Milky Way. The Gaia FGK benchmark stars play a central role in this matter as they are calibration pillars for the atmospheric parameters and chemical abundances for various surveys. The spectroscopic analyses of the benchmark stars are done by combining different methods, and the results will be affected by the systematic uncertainties inherent in each method. In this paper, we explore some of these systematic uncertainties. We determined line abundances of Ca, Cr, Mn and Co for four benchmark stars using six different methods. We changed the default input parameters of the different codes in a systematic way and found, in some cases, significant differences between the results. Since there is no consensus on the correct values for many of these default parameters, we urge the community to raise discussions towards standard input parameters that could alleviate the difference in abundances obtained by different methods. In this work, we provide quantitative estimates of uncertainties in elemental abundances due to the effect of differing technical assumptions in spectrum modelling. [ABSTRACT FROM AUTHOR]
Published: 2017
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15. Infrared stellar populations in the central parts of the Milky Way galaxy

Author: van, Loon Jacco Th., Gilmore, G. F., Omont, A., Blommaert, J. A. D. L., Glass, I. S., Messineo, M., Schuller, F., Schultheis, M., Zhao, H. S., Yamamura, Issei, Institut d'Astrophysique de Paris (IAP), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), and Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Physics, Milky Way, Metallicity, Astrophysics (astro-ph), Extinction (astronomy), FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Stellar classification, 01 natural sciences, Galaxy, [PHYS.ASTR.CO]Physics [physics]/Astrophysics [astro-ph]/Cosmology and Extra-Galactic Astrophysics [astro-ph.CO], Stars, Space and Planetary Science, Bulge, 0103 physical sciences, Asymptotic giant branch, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 010306 general physics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Near- and mid-IR survey data from DENIS and ISOGAL are used to investigate the structure and formation history of the inner 10 degree (1.4 kpc) of the Milky Way galaxy. Synthetic bolometric corrections and extinction coefficients in the near- and mid-IR are derived for stars of different spectral types, to allow the transformation of theoretical isochrones into observable colour-magnitude diagrams. The observed IR colour-magnitude diagrams are used to derive the extinction, metallicity and age for individual stars. The inner galaxy is dominated by an old population (> 7 Gyr). In addition, an intermediate-age population (200 Myr to 7 Gyr) is detected, which is consistent with the presence of a few hundred Asymptotic Giant Branch stars with heavy mass loss. Furthermore, young stars (< 200 Myr) are found across the inner Bulge. The metallicities of these stellar population components are discussed. These results can be interpreted in terms of an early epoch of intense star formation and chemical enrichment which shaped the bulk of the Bulge and nucleus, and a more continuous star formation history which gradually shaped the disk from the accretion of sub-solar metallicity gas from the halo. A possible increase in star formation about 200 Myr ago might have been triggered by a minor merger. Ever since the formation of the first stars, mechanisms have been at play that mix the populations from the nucleus, Bulge and disk. Luminosity functions across the inner galactic plane indicate the presence of an inclined (bar) structure at > 1 kpc from the galactic centre, near the inner Lindblad resonance. The innermost part of the Bulge, within about 1 kpc from the galactic centre, seems azimuthally symmetric., (25 pages, 31 figures, includes mn2e.cls; better quality figures 5, 13 and 21 available on request from Jacco: jacco@astro.keele.ac.uk) Accepted for publication in MNRAS
Published: 2003

16. The Gaia-ESO Survey: the selection function of the Milky Way field stars.

Author: StonkutStonkutė, E., Koposov, S. E., Howes, L. M., Feltzing, S., Worley, C. C., Gilmore, G., Ruchti, G. R., Kordopatis, G., Randich, S., Zwitter, T., Bensby, T., Bragaglia, A., Costado, M. T., Tautvaišienė, G., Casey, A. R., Korn, A. J., Lanzafame, A. C., Pancino, E., Franciosini, E., and Hourihane, A.
Subjects: SPECTROGRAPHS, MILKY Way, OPEN clusters of stars, ASTRONOMICAL instruments, ASTRONOMICAL photography
Abstract: The Gaia-ESO Survey was designed to target all major Galactic components (i.e. bulge, thin and thick discs, halo and clusters), with the goal of constraining the chemical and dynamical evolution of the Milky Way. This paper presents the methodology and considerations that drive the selection of the targeted, allocated and successfully observed Milky Way field stars. The detailed understanding of the survey construction, specifically the influence of target selection criteria on observed Milky Way field stars is required in order to analyse and interpret the survey data correctly. We present the target selection process for the Milky Way field stars observed with Very Large Telescope/Fibre Large Array Multi Element Spectrograph and provide the weights that characterize the survey target selection. The weights can be used to account for the selection effects in the Gaia-ESO Survey data for scientific studies. We provide a couple of simple examples to highlight the necessity of including such information in studies of the stellar populations in the Milky Way. [ABSTRACT FROM AUTHOR]
Published: 2016
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17. Climbing the cosmic ladder with stellar twins.

Author: Jofré, P., Mädler, T., Gilmore, G., Casey, A. R., Soubiran, C., and Worley, C.
Subjects: COSMIC rays, STELLAR evolution, THREE-dimensional imaging, PARALLAX, MILKY Way
Abstract: Distances to stars are key to revealing a three-dimensional view of the Milky Way, yet their determination is a major challenge in astronomy. Whilst the brightest nearby stars benefit from direct parallax measurements, fainter stars are subject of indirect determinations with uncertainties exceeding 30 per cent. We present an alternative approach to measuring distances using spectroscopically identified twin stars. Given a star with known parallax, the distance to its twin is assumed to be directly related to the difference in their apparent magnitudes. We found 175 twin pairs from the science public archive of the European Southern Observatory (ESO) archives and report excellent agreement with Hipparcos parallaxes within 7.5 per cent. Most importantly, the accuracy of our results does not degrade with increasing stellar distance. With the ongoing collection of high-resolution stellar spectra, our method is well suited to complement Gaia. [ABSTRACT FROM AUTHOR]
Published: 2015
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18. GROUND BASED FOLLOW-UP FOR GAIA SCIENCE ALERTS: FIRST RESULTS.

Author: Fraser, M., Altavilla, G., Blagorodnova, N., Campbell, H. C., Clementini, G., de Miguel, E., Gilmore, G., Hodgkin, S. T., Jonker, P. G., Koposov, S., Rixon, G., Rybicki, K., Torres, M. A. R., van Leeuwen, F., van Velzen, S., Walton, N. A., Wevers, T., Wielgørski, P., and Wyrzykowski, Ł.
Subjects: ASTRONOMICAL surveys, ASTRONOMICAL spectroscopy, ASTRONOMICAL research, MILKY Way
Abstract: The Gaia Science Alerts project (GSA) aims to augment a precision survey of the Milky Way with a controlled, precision survey of all classes of transient phenomena. While onboard BP/RP spectra from Gaia will ultimately allow us to classify many Gaia Alerts based on Gaia data alone, in the initial phases of the GSA project it is necessary to verify and classify discoveries with ground-based spectroscopic followup. In this article, we describe a subset of the ongoing Gaia Alerts followup programmes, and some of the initial science results from this work. [ABSTRACT FROM AUTHOR]
Published: 2014
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19. The Gaia-ESO Survey: α-abundances of metal-poor stars.

Author: Jackson-Jones, R., Jofré, P., Hawkins, K., Hourihane, A., Gilmore, G., Kordopatis, G., Worley, C., Costado, M. T., Lardo, C., Tautvaišieneė, G., Randich, S., Vallenari, A., Zaggia, S., Bensby, T., Bragaglia, A., Flaccomio, E., Korn, A. J., Heiter, U., Recio-Blanco, A., and Hill, V.
Subjects: GALACTIC halos, MILKY Way, STAR formation
Abstract: We performed a detailed study of the ratio of low-α to high-α stars in the Galactic halo as observed by the Gaia-ESO Survey. Using a sample of 381 metal-poor stars from the second internal data release, we found that the value of this ratio did not show evidence of systematic trends as a function of metallicity, surface gravity, Galactic latitude, Galactic longitude, height above the Galactic plane, and Galactocentric radius. We conclude that the αpoor/αrich value of 0.28± 0.08 suggests that in the inner halo, the larger portion of stars were formed in a high star formation rate environment, and about 15% of the metal-poor stars originated from much lower star formation rate environments. [ABSTRACT FROM AUTHOR]
Published: 2014
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20. Are dSph galaxies Galactic building blocks?

Author: Gilmore, G. and Asiri, H. M.
Subjects: *ELLIPTICAL galaxies, *GALAXY formation, *GALACTIC halos, *STELLAR populations, *MILKY Way
Abstract: Dwarf spheroidal galaxies (dSph) are frequently assumed to represent surviving examples of a vast now destroyed population of small systems in which many of the stars now forming the Milky Way were formed. Ongoing accretion and considerable sub-structure in the outer Galactic halo is direct evidence that there is some role for stars formed in small galaxies in populating the (outer) galaxy. The evidence from stellar populations is however contradictory to this. dSph stellar populations are unlike any stars found in significant numbers in the Milky Way. The dSph are indeed small galaxies, formed over long times with low rates of star formation. Most of the stars in the Milky Way halo however seem to have formed quickly, at higher star formation rate, in gas mixed efficiently on kpc scales. The overwhelming majority of Milky Way stars, those in the Galactic thick disk and thin disk, seem to have nothing at all to do with dwarf galaxy origins. [ABSTRACT FROM AUTHOR]
Published: 2012
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21. The Gaia-ESO Survey: metallicity and kinematic trends in the Milky Way bulge.

Author: Rojas-Arriagada, A., Recio-Blanco, A., Hill, V., de Laverny, P., Schultheis, M., Babusiaux, C., Zoccali, M., Minniti, D., Gonzalez, O. A., Feltzing, S., Gilmore, G., Randich, S., Vallenari, A., Alfaro, E. J., Bensby, T., Bragaglia, A., Flaccomio, E., Lanzafame, A. C., Pancino, E., and Smiljanic, R.
Subjects: MILKY Way, GALAXY formation, COSMIC abundances, GALACTIC bulges, STELLAR populations, RADIAL velocity of stars
Abstract: Aims. Observational studies of the MilkyWay bulge are providing increasing evidence of its complex chemo-dynamical patterns and morphology. Our intent is to use the iDR1 Gaia-ESO Survey (GES) data set to provide new constraints on the metallicity and kinematic trends of the Galactic bulge, exploring the viability of the currently proposed formation scenarios. Methods. We analyzed the stellar parameters and radial velocities of ~1200 stars in five bulge fields wich are located in the region -10° < l < 7° and -10° < b < -4°.We use VISTA Variables in the Via Lactea (VVV) photometry to verify the internal consistency of the atmospheric parameters recommended by the consortium. As a by-product, we obtained reddening values using a semi-empirical Teff -color calibration.We constructed the metallicity distribution functions and combined them with photometric and radial velocity data to analyze the properties of the stellar populations in the observed fields. Results. From a Gaussian decomposition of the metallicity distribution functions, we unveil a clear bimodality in all fields, with the relative size of components depending of the specific position on the sky. In agreement with some previous studies, we find a mild gradient along the minor axis (-0.05 dex/deg between b = -6° and b = -10°) that arises from the varying proportion of metal-rich and metal-poor components. The number of metal-rich stars fades in favor of the metal-poor stars with increasing b. The K-magnitude distribution of the metal-rich population splits into two peaks for two of the analyzed fields that intersects the near and far branches of the X-shaped bulge structure. In addition, two lateral fields at (l; b) = (7; -9) and (l; b) = (-10; -8) present contrasting characteristics. In the former, the metallicity distribution is dominated by metal-rich stars, while in the latter it presents a mix of a metal-poor population and and a metal-intermediate one, of nearly equal sizes. Finally, we find systematic di erences in the velocity dispersion between the metal-rich and the metal-poor components of each field. Conclusions. The iDR1 bulge data show chemo-dynamical distributions that are consistent with varying proportions of stars belonging to (i) a metal-rich boxy/peanut X-shaped component, with bar-like kinematics; and (ii) a metal-poor more extended rotating structure with a higher velocity dispersion that dominates far from the Galactic plane. These first GES data already allow studying the detailed spatial dependence of the Galactic bulge populations, thanks to the analysis of individual fields with relatively high statistics. [ABSTRACT FROM AUTHOR]
Published: 2014
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22. Chemical gradients in the Milky Way from the RAVE data: II. Giant stars.

Author: Boeche, C., Siebert, A., Piffl, T., Just, A., Steinmetz, M., Grebel, E. K., Sharma, S., Kordopatis, G., Gilmore, G., Chiappini, C., Freeman, K., Gibson, B. K., Munari, U., Siviero, A., Bienaymé, O., Navarro, J. F., Parker, Q. A., Reid, W., Seabroke, G. M., and Watson, F. G.
Subjects: GIANT stars, GALACTIC center, METAL-poor stars, COSMIC abundances, MILKY Way
Abstract: Aims. We provide new constraints on the chemo-dynamical models of the Milky Way by measuring the radial and vertical chemical gradients for the elements Mg, Al, Si, Ti, and Fe in the Galactic disc and the gradient variations as a function of the distance from the Galactic plane (Z). Methods. We selected a sample of giant stars from the RAVE database using the gravity criterium 1.7 < logg < 2.8. We created a RAVE mock sample with the Galaxia code based on the Besançon model and selected a corresponding mock sample to compare the model with the observed data. We measured the radial gradients and the vertical gradients as a function of the distance from the Galactic plane Z to study their variation across the Galactic disc. Results. The RAVE sample exhibits a negative radial gradient of d[Fe/H]/dR = –0.054 dex kpc-1 close to the Galactic plane (∣Z∣ < 0.4 kpc) that becomes flatter for larger ∣Z∣. Other elements follow the same trend although with some variations from element to element. The mock sample has radial gradients in fair agreement with the observed data. The variation of the gradients with Z shows that the Fe radial gradient of the RAVE sample has little change in the range ∣Z∣ ≲ 0.6 kpc and then flattens. The iron vertical gradient of the RAVE sample is slightly negative close to the Galactic plane and steepens with ∣Z∣. The mock sample exhibits an iron vertical gradient that is always steeper than the RAVE sample. The mock sample also shows an excess of metal-poor stars in the [Fe/H] distributions with respect to the observed data. These discrepancies can be reduced by decreasing the number of thick disc stars and increasing their average metallicity in the Besançon model. [ABSTRACT FROM AUTHOR]
Published: 2014
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23. The Gaia-ESO Survey: radial metallicity gradients and age-metallicity relation of stars in the Milky Way disk.

Author: Bergemann, M., Ruchti, G. R., Serenelli, A., Feltzing, S., Alves-Brito, A., Asplund, M., Bensby, T., Gruiters, P., Heiter, U., Hourihane, A., Korn, A., Lind, K., Marino, A., Jofre, P., Nordlander, T., Ryde, N., Worley, C. C., Gilmore, G., Randich, S., and Ferguson, A. M. N.
Subjects: MILKY Way, GALAXY formation, DISTRIBUTION (Probability theory), PLANETARY nebulae, DISKS (Astrophysics), SPECTRUM analysis
Abstract: We study the relationship between age, metallicity, and α-enhancement of FGK stars in the Galactic disk. The results are based upon the analysis of high-resolution UVES spectra from the Gaia-ESO large stellar survey. We explore the limitations of the observed dataset, i.e. the accuracy of stellar parameters and the selection effects that are caused by the photometric target preselection. We find that the colour and magnitude cuts in the survey suppress old metal-rich stars and young metal-poor stars. This suppression may be as high as 97% in some regions of the age-metallicity relationship. The dataset consists of 144 stars with a wide range of ages from 0.5 Gyr to 13.5 Gyr, Galactocentric distances from 6 kpc to 9.5 kpc, and vertical distances from the plane 0 < ∣Z∣ < 1.5 kpc. On this basis, we find that i) the observed age-metallicity relation is nearly flat in the range of ages between 0 Gyr and 8 Gyr; ii) at ages older than 9 Gyr, we see a decrease in [Fe/H] and a clear absence of metal-rich stars; this cannot be explained by the survey selection functions; iii) there is a significant scatter of [Fe/H] at any age; and iv) [Mg/Fe] increases with age, but the dispersion of [Mg/Fe] at ages >9 Gyr is not as small as advocated by some other studies. In agreement with earlier work, we find that radial abundance gradients change as a function of vertical distance from the plane. The [Mg/Fe] gradient steepens and becomes negative. In addition, we show that the inner disk is not only more α-rich compared to the outer disk, but also older, as traced independently by the ages and Mg abundances of stars. [ABSTRACT FROM AUTHOR]
Published: 2014
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24. Gaia-ESO Survey: processing FLAMES-UVES spectra.

Author: Sacco, G. G., Morbidelli, L., Franciosini, E., Maiorca, E., Randich, S., Modigliani, A., Gilmore, G., Asplund, M., Binney, J., Bonifacio, P., Drew, J., Feltzing, S., Ferguson, A., Jeffries, R., Micela, G., Negueruela, I., Prusti, T., Rix, H.-W., Vallenari, A., and Alfaro, E.
Subjects: ASTRONOMICAL surveys, ASTRONOMICAL spectroscopy, RADIAL velocity of stars, GALAXY spectra, MILKY Way
Abstract: The Gaia-ESO Survey is a large public spectroscopic survey that aims to derive radial velocities and fundamental parameters of about 105 Milky Way stars in the field and in clusters. Observations are carried out with the multi-object optical spectrograph FLAMES, using simultaneously the medium-resolution (R ~ 20 000) GIRAFFE spectrograph and the high-resolution (R ~ 47 000) UVES spectrograph. In this paper we describe the methods and the software used for the data reduction, the derivation of the radial velocities, and the quality control of the FLAMES-UVES spectra. Data reduction has been performed using a workflow specifically developed for this project. This workflow runs the ESO public pipeline optimizing the data reduction for the Gaia-ESO Survey, automatically performs sky subtraction, barycentric correction and normalisation, and calculates radial velocities and a first guess of the rotational velocities. The quality control is performed using the output parameters from the ESO pipeline, by a visual inspection of the spectra and by the analysis of the signal-to-noise ratio of the spectra. Using the observations of the first 18 months, specifically targets observed multiple times at different epochs, stars observed with both GIRAFFE and UVES, and observations of radial velocity standards, we estimated the precision and the accuracy of the radial velocities. The statistical error on the radial velocities is σ ~ 0.4 kms-1 and is mainly due to uncertainties in the zero point of the wavelength calibration. However, we found a systematic bias with respect to the GIRAFFE spectra (~0.9 kms-1) and to the radial velocities of the standard stars (~0.5 kms-1) retrieved from the literature. This bias will be corrected in the future data releases, when a common zero point for all the set-ups and instruments used for the survey is be established. [ABSTRACT FROM AUTHOR]
Published: 2014
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25. Constraints on the Galactic bar from the Hercules stream as traced with RAVE across the Galaxy.

Author: Antoja, T., Helmi, A., Dehnen, W., Bienaymé, O., Bland-Hawthorn, J., Famaey, B., Freeman, K., Gibson, B. K., Gilmore, G., Grebel, E. K., Kordopatis, G., Kunder, A., Minchev, I., Munari, U., Navarro, J., Parker, Q., Reid, W. A., Seabroke, G., Siebert, A., and Steinmetz, M.
Subjects: CONSTRAINTS (Physics), OPEN clusters of stars, GALACTIC evolution, KINEMATICS, MILKY Way
Abstract: Non-axisymmetries in the Galactic potential (spiral arms and bar) induce kinematic groups such as the Hercules stream. Assuming that Hercules is caused by the effects of the outer Lindblad resonance of the Galactic bar, we model analytically its properties as a function of position in the Galaxy and its dependence on the bar's pattern speed and orientation. Using data from the RAVE survey we find that the azimuthal velocity of the Hercules structure decreases as a function of Galactocentric radius, in a manner consistent with our analytical model. This allows us to obtain new estimates of the parameters of the Milky Way's bar. The combined likelihood function of the bar's pattern speed and angle has its maximum for a pattern speed of Ωb = (1.89 ± 0.08) × Ω0, where Ω0 is the local circular frequency. Assuming a solar radius of 8.05 kpc and a local circular velocity of 238 km s-1, this corresponds to Ωb = 56 ± 2kms-1 kpc-1. On the other hand, the bar's orientation ϕb cannot be constrained with the available data. In fact, the likelihood function shows that a tight correlation exists between the pattern speed and the orientation, implying that a better description of our best fit results is given by the linear relation Ωb/Ω0 = 1.91+0.0044 (ϕb(deg) - 48), with standard deviation of 0.02. For example, for an angle of ϕb = 30 deg the pattern speed is 54.0 ± 0.5kms-1 kpc-1. These results are not very sensitive to the other Galactic parameters such as the circular velocity curve or the peculiar motion of the Sun, and are robust to biases in distance. [ABSTRACT FROM AUTHOR]
Published: 2014
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26. The RAVE survey: the Galactic escape speed and the mass of the Milky Way.

Author: Piffl, T., Scannapieco, C., Binney, J., Steinmetz, M., Scholz, R.-D., Williams, M. E. K., de Jong, R. S., Kordopatis, G., Matijevič, G., Bienaymé, O., Bland-Hawthorn, J., Boeche, C., Freeman, K., Gibson, B., Gilmore, G., Grebel, E. K., Helmi, A., Munari, U., Navarro, J. F., and Parker, Q.
Subjects: GALACTIC dynamics, KINEMATICS, GALACTIC halos, STELLAR structure, INFLATIONARY universe, DARK matter, STELLAR mass, MILKY Way
Abstract: We made new estimates of the Galactic escape speed at various Galactocentric radii using the latest data release of the RAdial Velocity Experiment (RAVE DR4). Compared to previous studies we have a database that is larger by a factor of 10, as well as reliable distance estimates for almost all stars. Our analysis is based on statistical analysis of a rigorously selected sample of 90 highvelocity halo stars from RAVE and a previously published data set. We calibrated and extensively tested our method using a suite of cosmological simulations of the formation of Milky Way-sized galaxies. Our best estimate of the local Galactic escape speed, which we define as the minimum speed required to reach three virial radii R340, is 533+54 -41 km s-1 (90% confidence), with an additional 4% systematic uncertainty, where R340 is the Galactocentric radius encompassing a mean overdensity of 340 times the critical density for closure in the Universe. From the escape speed we further derived estimates of the mass of the Galaxy using a simple mass model with two options for the mass profile of the dark matter halo: an unaltered and an adiabatically contracted Navarro, Frenk & White (NFW) sphere. If we fix the local circular velocity, the latter profile yields a significantly higher mass than the uncontracted halo, but if we instead use the statistics for halo concentration parameters in large cosmological simulations as a constraint, we find very similar masses for both models. Our best estimate for M340, the mass interior to R340 (dark matter and baryons), is 1.3+0.4 -0.3 × 1012 M☉ (corresponds to M200 = 1.6+0.5 -0.4 × 1012 M☉). This estimate is in good agreement with recently published, independent mass estimates based on the kinematics of more distant halo stars and the satellite galaxy Leo I. [ABSTRACT FROM AUTHOR]
Published: 2014
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27. A RAVE investigation on Galactic open clusters I. Radial velocities and metallicities.

Author: Conrad, C., Scholz, R. D., Kharchenko, N. V., Piskunov, A. E., Schilbach, E., Röser, S., Boeche, C., Kordopatis, G., Siebert, A., Williams, M., Munari, U., Matijevič, G., Grebel, E. K., Zwitter, T., de Jong, R. S., Steinmetz, M., Gilmore, G., Seabroke, G., Freeman, K., and Navarro, J. F.
Subjects: GALAXY clusters, STAR clusters, DISKS (Astrophysics), STAR formation, RADIAL velocity of galaxies, COSMIC abundances, MILKY Way
Abstract: Context. Galactic open clusters (OCs) mainly belong to the young stellar population in the Milky Way disk, but are there groups and complexes of OCs that possibly define an additional level in hierarchical star formation? Current compilations are too incomplete to address this question, especially regarding radial velocities (RVs) and metallicities ([M/H]). Aims. Here we provide and discuss newly obtained RV and [M/H] data, which will enable us to reinvestigate potential groupings of open clusters and associations. Methods. We extracted additional RVs and [M/H] from the RAdial Velocity Experiment (RAVE) via a cross-match with the Catalogue of Stars in Open Cluster Areas (CSOCA). For the identified OCs in RAVE we derived RV and [M/H] from a cleaned working sample and compared the results with previous findings. Results. Although our RAVE sample does not show the same accuracy as the entire survey, we were able to derive reliable RV for 110 Galactic open clusters. For 37 OCs we publish RV for the first time. Moreover, we determined [M/H] for 81 open clusters, extending the number of OCs with [M/H] by 69. [ABSTRACT FROM AUTHOR]
Published: 2014
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28. Chemical gradients in the Milky Way from the RAVE data I. Dwarf stars.

Author: Boeche, C., Siebert, A., Piffl, T., Just, A., Steinmetz, M., Sharma, S., Kordopatis, G., Gilmore, G., Chiappini, C., Williams, M., Grebel, E. K., Bland-Hawthorn, J., Gibson, B. K., Munari, U., Siviero, A., Bienaymé, O., Navarro, J. F., Parker, Q. A., Reid, W., and Seabroke, G. M.
Subjects: DWARF stars, GALACTIC evolution, STELLAR orbits, LIGHT metals, MOLECULAR evolution, STELLAR structure, COSMIC abundances, ASTRONOMICAL models, MILKY Way
Abstract: Aims. We aim at measuring the chemical gradients of the elements Mg, Al, Si, and Fe along the Galactic radius to provide new constraints on the chemical evolution models of the Galaxy and Galaxy models such as the Besançon model. Thanks to the large number of stars of our RAVE sample we can study how the gradients vary as function of the distance from the Galactic plane. Methods. We analysed three different samples selected from three independent datasets: a sample of 19 962 dwarf stars selected from the RAVE database, a sample of 10 616 dwarf stars selected from the Geneva-Copenhagen Survey (GCS) dataset, and a mock sample (equivalent to the RAVE sample) created by using the GALAXIA code, which is based on the Besançon model. The three samples were analysed by using the very same method for comparison purposes. We integrated the Galactic orbits and obtained the guiding radii (Rg) and the maximum distances from the Galactic plane reached by the stars along their orbits (Zmax).We measured the chemical gradients as functions of Rg at different Zmax. Results. We found that the chemical gradients of the RAVE and GCS samples are negative and show consistent trends, although they are not equal: at Zmax < 0.4 kpc and 4.5 < Rg(kpc) < 9.5, the iron gradient for the RAVE sample is d[Fe/H]/dRg = -0.065 dex kpc-1, whereas for the GCS sample it is d[Fe/H]/dRg = -0.043 dex kpc-1 with internal errors of ±0.002 and ±0.004 dex kpc-1, respectively. The gradients of the RAVE and GCS samples become flatter at larger Zmax. Conversely, the mock sample has a positive iron gradient of d[Fe/H]/dRg = +0.053 ± 0.003 dex kpc-1 at Zmax < 0.4 kpc and remains positive at any Zmax. These positive and unrealistic values originate from the lack of correlation between metallicity and tangential velocity in the Besançon model. In addition, the low metallicity and asymmetric drift of the thick disc causes a shift of the stars towards lower Rg and metallicity which, together with the thin-disc stars with a higher metallicity and Rg, generates a fictitious positive gradient of the full sample. The flatter gradient at larger Zmax found in the RAVE and the GCS samples may therefore be due to the superposition of thin- and thick-disc stars, which mimicks a flatter or positive gradient. This does not exclude the possibility that the thick disc has no chemical gradient. The discrepancies between the observational samples and the mock sample can be reduced by i) decreasing the density; ii) decreasing the vertical velocity; and iii) increasing the metallicity of the thick disc in the Besançon model. [ABSTRACT FROM AUTHOR]
Published: 2013
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29. Testing formation mechanisms of the Milky Way's thick disc with RAVE.

Author: Wilson, Michelle L., Helmi, Amina, Morrison, Heather L., Breddels, Maarten A., Bienaymé, O., Binney, J., Bland-Hawthorn, J., Campbell, R., Freeman, K. C., Fulbright, J. P., Gibson, B. K., Gilmore, G., Grebel, E. K., Munari, U., Navarro, J. F., Parker, Q. A., Reid, W., Seabroke, G., Siebert, A., and Siviero, A.
Subjects: GALAXY formation, DISKS (Astrophysics), PHYSICS experiments, ASTRONOMICAL observations, DISTRIBUTION of stars, STAR formation, MILKY Way
Abstract: We study the eccentricity distribution of a thick-disc sample of stars (defined as those with and ) observed in the Radial Velocity Experiment (RAVE). We compare this distribution with those obtained in four simulations of galaxy formation taken from the literature as compiled by Sales et al. Each simulation emphasizes different scenarios for the origin of such stars (satellite accretion, heating of a pre-existing thin disc during a merger, radial migration, and gas-rich mergers). We find that the observed distribution peaks at low eccentricities and falls off smoothly and rather steeply to high eccentricities. This finding is fairly robust to changes in distances and to plausible assumptions about thin-disc contamination. Our results favour models where the majority of stars formed in the Galaxy itself on orbits of modest eccentricity and disfavour the pure satellite accretion case. A gas-rich merger origin where most of the stars form ' in situ' appears to be the most consistent with our data. [ABSTRACT FROM AUTHOR]
Published: 2011
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30. Local stellar kinematics from RAVE data - I. Local standard of rest.

Author: Coşkunoğlu, B., Ak, S., Bilir, S., Karaali, S., Yaz, E., Gilmore, G., Seabroke, G. M., Bienaymé, O., Bland-Hawthorn, J., Campbell, R., Freeman, K. C., Gibson, B., Grebel, E. K., Munari, U., Navarro, J. F., Parker, Q. A., Siebert, A., Siviero, A., Steinmetz, M., and Watson, F. G.
Subjects: STELLAR dynamics, KINEMATICS, F stars, RADIAL velocity of stars, SCIENTIFIC surveys, DWARF stars, DISKS (Astrophysics), MILKY Way
Abstract: We analyse a sample of 82 850 stars from the RAdial Velocity Experiment (RAVE) survey, with well-determined velocities and stellar parameters, to isolate a sample of 18 026 high-probability thin-disc dwarfs within 600 pc of the Sun. We derive space motions for these stars, and deduce the solar space velocity with respect to the local standard of rest. The peculiar solar motion we derive is in excellent agreement in radial and vertical peculiar motions with other recent determinations. Our derived tangential peculiar velocity, , agrees with very recent determinations, which favour values near 13 km s, in disagreement with earlier studies. The derived values are not significantly dependent on the comparison sample chosen, or on the method of analysis. The local Galaxy seems very well dynamically relaxed, in a near symmetric potential. [ABSTRACT FROM AUTHOR]
Published: 2011
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31. Kinematics of SDSS subdwarfs: structure and substructure of the Milky Way halo.

Author: Smith, M. C., Evans, N. W., Belokurov, V., Hewett, P. C., Bramich, D. M., Gilmore, G., Irwin, M. J., Vidrih, S., and Zucker, D. B.
Subjects: DWARF stars, GALAXIES, SPECTRUM analysis, ASTRONOMY, MILKY Way
Abstract: We construct a new sample of ∼1700 solar neighbourhood halo subdwarfs from the Sloan Digital Sky Survey (SDSS), selected using a reduced proper-motion diagram. Radial velocities come from the SDSS spectra and proper motions from the light-motion curve catalogue of Bramich et al. Using a photometric parallax relation to estimate distances gives us the full phase-space coordinates. Typical velocity errors are in the range . This halo sample is one of the largest constructed to date and the disc contamination is at a level of ≲1 per cent. This enables us to calculate the halo velocity dispersion to excellent accuracy. We find that the velocity dispersion tensor is aligned in spherical polar coordinates and that . The stellar halo exhibits no net rotation, although the distribution of shows tentative evidence for asymmetry. The kinematics are consistent with a mildly flattened stellar density falling with distance like . Using the full phase-space coordinates, we look for signs of kinematic substructure in the stellar halo. We find evidence for four discrete overdensities localized in angular momentum and suggest that they may be possible accretion remnants. The most prominent is the solar neighbourhood stream previously identified by Helmi et al., but the remaining three are new. One of these overdensities is potentially associated with a group of four globular clusters (NGC 5466, NGC 6934, M2 and M13) and raises the possibility that these could have been accreted as part of a much larger progenitor. [ABSTRACT FROM AUTHOR]
Published: 2009
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32. The origin of Segue 1.

Author: Niederste-Ostholt, M., Belokurov, V., Evans, N. W., Gilmore, G., Wyse, R. F. G., and Norris, J. E.
Subjects: PHOTOMETRY, ELECTROMAGNETIC measurements, STAR clusters, SPEED, MILKY Way, GALAXIES
Abstract: We apply the optimal filter technique to Sloan Digital Sky Survey photometry around Segue 1 and find that the outer parts of the cluster are distorted. There is strong evidence for elongations of extra-tidal stars, extending both eastwards and southwestwards of the cluster. The extensions have similar differential Hess diagrams to Segue 1. A Kolmogorov–Smirnov test suggests a high probability that both come from the same parent distribution. The location of Segue 1 is close to crossings of the tidal wraps of the Sagittarius stream. By extracting blue horizontal branch stars from Sloan's spectral data base, two kinematic features are isolated and identified with different wraps of the Sagittarius stream. We show that Segue 1 is moving with a velocity that is close to one of the wraps. At this location, we estimate that there are enough Sagittarius stars, indistinguishable from Segue 1 stars, to inflate the velocity dispersion and hence the mass-to-light ratio. All the available evidence is consistent with the interpretation that Segue 1 is a star cluster, originally from the Sagittarius galaxy, and now dissolving in the Milky Way. [ABSTRACT FROM AUTHOR]
Published: 2009
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33. The discovery of Segue 2: a prototype of the population of satellites of satellites.

Author: Belokurov, V., Walker, M. G., Evans, N. W., Gilmore, G., Irwin, M. J., Mateo, M., Mayer, L., Olszewski, E., Bechtold, J., and Pickering, T.
Subjects: PROTOTYPES, SPECTRUM analysis, NATURAL satellites, SOLAR system, MILKY Way
Abstract: We announce the discovery of a new Milky Way satellite Segue 2 found in the data of the Sloan Extension for Galactic Understanding and Exploration (SEGUE). We followed this up with deeper imaging and spectroscopy on the Multiple Mirror Telescope (MMT). From this, we derive a luminosity of , a half-light radius of 34 pc and a systemic velocity of . Our data also provide evidence for a stream around Segue 2 at a similar heliocentric velocity, and the SEGUE data show that it is also present in neighbouring fields. We resolve the velocity dispersion of Segue 2 as 3.4 km s−1 and the possible stream as . This object shows points of comparison with other recent discoveries, Segue 1, Boo II and Coma. We speculate that all four objects may be representatives of a population of satellites of satellites – survivors of accretion events that destroyed their larger but less dense parents. They are likely to have formed at redshifts and are good candidates for fossils of the reionization epoch. [ABSTRACT FROM AUTHOR]
Published: 2009
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34. Estimation of the tilt of the stellar velocity ellipsoid from RAVE and implications for mass models.

Author: Siebert, A., Bienaymé, O., Binney, J., Bland-Hawthorn, J., Campbell, R., Freeman, K. C., Gibson, B. K., Gilmore, G., Grebel, E. K., Helmi, A., Munari, U., Navarro, J. F., Parker, Q. A., Seabroke, G., Siviero, A., Steinmetz, M., Williams, M., Wyse, R. F. G., and Zwitter, T.
Subjects: ASTEROIDS, GALAXIES, MILKY Way, ELLIPSOIDS, ASTRONOMICAL research, SPEED
Abstract: We present a measure of the inclination of the velocity ellipsoid at 1 kpc below the Galactic plane using a sample of red clump giants from the RAdial Velocity Experiment (RAVE) Data Release 2. We find that the velocity ellipsoid is tilted towards the Galactic plane with an inclination of . We compare this value to computed inclinations for two mass models of the Milky Way. We find that our measurement is consistent with a short scalelength of the stellar disc if the dark halo is oblate or with a long scalelength if the dark halo is prolate. Once combined with independent constraints on the flattening of the halo, our measurement suggests that the scalelength is approximately halfway between these two extreme values, with a preferred range 2.5–2.7 kpc for a nearly spherical halo. Nevertheless, no model can be clearly ruled out. With the continuation of the RAVE survey, it will be possible to provide a strong constraint on the mass distribution of the Milky Way using refined measurements of the orientation of the velocity ellipsoid. [ABSTRACT FROM AUTHOR]
Published: 2008
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35. Is the sky falling? Searching for stellar streams in the local Milky Way disc in the CORAVEL and RAVE surveys.

Author: Seabroke, G. M., Gilmore, G., Siebert, A., Bienaymé, O., Binney, J., Bland-Hawthorn, J., Campbell, R., Freeman, K. C., Gibson, B., Grebel, E. K., Helmi, A., Munari, U., Navarro, J. F., Parker, Q. A., Siviero, A., Steinmetz, M., Watson, F. G., Wyse, R. F. G., Zwitter, T., and Peñarrubia, J.
Subjects: *MILKY Way, *DWARF stars, *GIANT stars, *INTERSTELLAR medium, *DARK matter, *ASTRONOMY
Abstract: We have searched for in-falling stellar streams on to the local Milky Way disc in the CORrelation RAdial VELocities (CORAVEL) and RAdial Velocity Experiment (RAVE) surveys. The CORAVEL survey consists of local dwarf stars (Nördstrom et al. Geneva–Copenhagen survey) and local Famaey et al. giant stars. We select RAVE stars with radial velocities that are sensitive to the Galactic vertical space velocity (Galactic latitude b < −45°). Kuiper statistics have been employed to test the symmetry of the Galactic vertical velocity distribution functions in these samples for evidence of a net vertical flow that could be associated with a (tidal?) stream of stars with vertically coherent kinematics. In contrast to the ‘Field of Streams’ found in the outer halo, we find that the local volumes of the solar neighbourhood sampled by the CORAVEL dwarfs (complete within ∼3 × 10−4 kpc3), CORAVEL giants (complete within ∼5 × 10−2 kpc3) and RAVE (5–15 per cent complete within ∼8 kpc3) are devoid of any vertically coherent streams containing hundreds of stars. This is sufficiently sensitive to allow our RAVE sample to rule out the passing of the tidal stream of the disrupting Sagittarius (Sgr) dwarf galaxy through the solar neighbourhood. This agrees with the most-recent determinations of its orbit and dissociates it from the Helmi et al. halo stream. Our constraints on the absence of the Sgr stream near the Sun could prove a useful tool for discriminating between Galactic potential models. The lack of a net vertical flow through the solar neighbourhood in the CORAVEL giants and RAVE samples argues against the Virgo overdensity crossing the disc near the Sun. There are no vertical streams in the CORAVEL giants and RAVE samples with stellar densities ≳1.6 × 104 and 1.5 × 103 stars kpc−3, respectively, and therefore no evidence for locally enhanced dark matter. [ABSTRACT FROM AUTHOR]
Published: 2008
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36. The tidal tails of NGC 5466.

Author: Fellhauer, M., Evans, N. W., Belokurov, V., Wilkinson, M. I., and Gilmore, G.
Subjects: STELLAR dynamics, MILKY Way, SURVEYS, GLOBULAR clusters, GALAXIES, KINEMATICS, ASTRONOMICAL research
Abstract: The study of substructure in the stellar halo of the Milky Way has made a lot of progress in recent years, especially with the advent of surveys like the Sloan Digital Sky Survey (SDSS). Here, we study the newly discovered tidal tails of the Galactic globular cluster NGC 5466. By means of numerical simulations, we reproduce the shape, direction and surface density of the tidal tails, as well as the structural and kinematical properties of the present-day NGC 5466. Although its tails are very extended in SDSS data ), NGC 5466 is only losing mass slowly at the present epoch and so can survive for probably a further Hubble time. The effects of tides at perigalacticon and disc-crossing are the dominant causes of the slow dissolution of NGC 5466, accounting for ≳60 per cent of the mass loss over the course of its evolution. The morphology of the tails provides a constraint on the proper motion – the observationally determined proper motion has to be refined (within the stated error margin) to match the location of the tidal tails. [ABSTRACT FROM AUTHOR]
Published: 2007
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37. Infrared stellar populations in the central parts of the Milky Way galaxy.

Author: Loon, Jacco Th. van, Gilmore, G. F., Omont, A., Blommaert, J. A. D. L., Glass, I. S., Messineo, M., Schuller, F., Schultheis, M., Yamamura, I., and Zhao, H. S.
Subjects: *STARS, *MILKY Way, *INFRARED astronomy
Abstract: Studies the structure and formation history of infrared stellar populations in central parts of the Milky Way. Extinction, metallicity and age of individual stars; Causes of increases in star formation; Luminosity functions across the inner galactic plane.
Published: 2003
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38. VizieR Online Data Catalog: RAVE 3rd data release (Siebert+, 2011)

Author: Siebert, A., Williams, M., Siviero, A., Reid, W., Boeche, C., Steinmetz, M., Fulbright, J., Munari, U., Zwitter, T., Watson, F. G., Wyse, R. F. G., de Jong, R. S., Enke, H., Anguiano, B., Burton, D., Cass, C. J. P., Fiegert, K., Hartley, M., Ritter, A., Russel, K. S., Stupar, M., Bienayme, O., Freeman, K. C., Gilmore, G., Grebel, E. K., Helmi, A., Navarro, J. F., Binney, J., Bland-Hawthorn, J., Campbell, R., Famaey, B., Gerhard, O., Gibson, B. K., Matijevic, G., Parker, Q. A., Seabroke, G. M., Sharma, S., Smith, M. C., Wylie-de Boer, E., and Kapteyn Astronomical Institute
Subjects: Milky Way, Photometry, Radial velocities, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, Stars: fundamental, Astrophysics::Galaxy Astrophysics
Abstract: Spectroscopic radial velocities for 83,072 stars in the Milky-Way southern hemisphere using the 6dF instrument at the AAO. Stellar parameters are published for a set of 39,833 stars belonging to the second and third years of observation. (1 data file).

39. RAVE DR2 distance catalogue (Breddels+, 2010)

Author: Breddels, M. A., Smith, M. C., Helmi, A., Bienayme, O., Binney, J., Bland-Hawthorn, J., Boeche, C., Burnett, B. C. M., Campbell, R., Freeman, K. C., Gibson, B., Gilmore, G., Grebel, E. K., Munari, U., Navarro, J. F., Parker, Q. A., Seabroke, G. M., Siebert, A., Siviero, A., Steinmetz, M., Watson, F. G., Williams, M., Wyse, R. F. G., Zwitter, T., and Astronomy
Subjects: Milky Way, Radial velocities, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Surveys, Stars: distances, Astrophysics::Galaxy Astrophysics
Abstract: We used stellar models combined with atmospheric properties from RAVE (effective temperature, surface gravity and metallicity) and (J-Ks) photometry from archival sources to derive absolute magnitudes. In combination with apparent magnitudes, sky coordinates, proper motions from a variety of sources and radial velocities from RAVE, we are able

40. RAVE 3rd data release (Siebert+, 2011)

Author: Siebert, A., Williams, M., Siviero, A., Reid, W., Boeche, C., Steinmetz, M., Fulbright, J., Munari, U., Zwitter, T., Watson, F. G., Wyse, R. F. G., de Jong, R.S., Enke, H., Anguiano, B., Burton, D., Cass, C. J. P., Fiegert, K., Hartley, M., Ritter, A., Russel, K. S., Stupar, M., Bienayme, O., Freeman, K. C., Gilmore, G., Grebel, E. K., Helmi, A., Navarro, J. F., Binney, J., Bland-Hawthorn, J., Campbell, R., Famaey, B., Gerhard, O., Gibson, B. K., Matijevic, G., Parker, Q. A., Seabroke, G. M., Sharma, S., Smith, M. C., Wylie-de Boer, E., and Astronomy
Subjects: Milky Way, Photometry, Radial velocities, Astrophysics::Instrumentation and Methods for Astrophysics, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, Stars: fundamental, Astrophysics::Galaxy Astrophysics
Abstract: Spectroscopic radial velocities for 83,072 stars in the Milky-Way southern hemisphere using the 6dF instrument at the AAO. Stellar parameters are published for a set of 39,833 stars belonging to the second and third years of observation.

41. A census of the Milky Way.

Author: Gilmore, G.
Subjects: *MILKY Way
Abstract: States that some of the limitations in making a reliable census of stars in the Milky Way are disappearing due to new technology and a revival of interest in the structure, evolution, and origin of our galaxy. Approximate number of luminous stars in the Milky Way; Recent surveys that agree in assigning kinematics to the thick-disk that are intermediate between the halo and disk populations; More.
Published: 1991
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42. KINEMATIC MODELING OF THE MILKY WAY USING THE RAVE AND GCS STELLAR SURVEYS.

Author: Sharma, S., Bland-Hawthorn, J., Binney, J., Freeman, K. C., Steinmetz, M., Boeche, C., Bienaymé, O., Gibson, B. K., Gilmore, G. F., Grebel, E. K., Helmi, A., Kordopatis, G., Munari, U., Navarro, J. F., Parker, Q. A., Reid, W. A., Seabroke, G. M., Siebert, A., Watson, F., and Williams, M. E. K.
Subjects: STAR observations, MILKY Way, DATA analysis, GALAXIES, KINEMATICS
Abstract: We investigate the kinematic parameters of the Milky Way disk using the Radial Velocity Experiment (RAVE) and Geneva-Copenhagen Survey (GCS) stellar surveys. We do this by fitting a kinematic model to the data and taking the selection function of the data into account. For stars in the GCS we use all phase-space coordinates, but for RAVE stars we use only (ℓ, b, vlos). Using the Markov Chain Monte Carlo technique, we investigate the full posterior distributions of the parameters given the data. We investigate the age-velocity dispersion relation for the three kinematic components (σR, σϕ, σz), the radial dependence of the velocity dispersions, the solar peculiar motion (U☼, V☼, W☼), the circular speed Θ0 at the Sun, and the fall of mean azimuthal motion with height above the midplane. We confirm that the Besançon-style Gaussian model accurately fits the GCS data but fails to match the details of the more spatially extended RAVE survey. In particular, the Shu distribution function (DF) handles noncircular orbits more accurately and provides a better fit to the kinematic data. The Gaussian DF not only fits the data poorly but systematically underestimates the fall of velocity dispersion with radius. The radial scale length of the velocity dispersion profile of the thick disk was found to be smaller than that of the thin disk. We find that correlations exist between a number of parameters, which highlights the importance of doing joint fits. The large size of the RAVE survey allows us to get precise values for most parameters. However, large systematic uncertainties remain, especially in V☼ and Θ0. We find that, for an extended sample of stars, Θ0 is underestimated by as much as 10% if the vertical dependence of the mean azimuthal motion is neglected. Using a simple model for vertical dependence of kinematics, we find that it is possible to match the Sgr A* proper motion without any need for V☼ being larger than that estimated locally by surveys like GCS. [ABSTRACT FROM AUTHOR]
Published: 2014
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43. The Gaia-ESO Survey: matching chemodynamical simulations to observations of the Milky Way

Author: Grazina Tautvaisiene, P. Francois, G. G. Sacco, Andreas Korn, B. B. Thompson, P. Donati, Gianni Marconi, Thomas Masseron, A. C. Lanzafame, A. Hourihane, Brad K. Gibson, Carmela Lardo, B. A. Macfarlane, Jack Lewis, Aldo Serenelli, E. Franciosini, E. Pancino, Antonio Frasca, L. Morbidelli, Sergey E. Koposov, P. de Laverny, Clare Worley, Simone Zaggia, Paula Jofre, Gerard Gilmore, L. Prisinzano, Lorenzo Monaco, V. Hill, Laura Magrini, C. G. Few, Ulrike Heiter, Emilio J. Alfaro, Andrew R. Casey, M. T. Costado, S. G. Sousa, Maria Bergemann, Giovanni Carraro, Antonella Vallenari, Thomas Bensby, Sofia Randich, Amelia Bayo, A. Recio-Blanco, Jeremiah Horrocks Insitute, University of Central Lancashire [Preston] (UCLAN), Institute of Space Sciences [Barcelona] (ICE-CSIC), Spanish National Research Council [Madrid] (CSIC), INAF - Osservatorio Astronomico di Padova (OAPD), Istituto Nazionale di Astrofisica (INAF), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Department of Physics and Astronomy [Uppsala], Uppsala University, Focas Research Institute, Dublin Institute of Technology, Institut national de recherche et de sécurité (Vandoeuvre lès Nancy) (INRS ( Vandoeuvre lès Nancy)), INAF - Osservatorio Astrofisico di Catania (OACT), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Istituto Nazionale di Fisica Nucleare, Sezione di Milano (INFN), Istituto Nazionale di Fisica Nucleare (INFN), INAF - Osservatorio Astronomico di Bologna (OABO), Universidade de Sao Paulo, Instituto Ocenografico, Science and Technology Facilities Council (UK), European Research Council, Knut and Alice Wallenberg Foundation, Fundação para a Ciência e a Tecnologia (Portugal), European Commission, Swedish National Space Board, Leverhulme Trust, Istituto Nazionale di Astrofisica, European Science Foundation, Ministerio de Economía y Competitividad (España), German Research Foundation, National Science Foundation (US), Australian Research Council, Gilmore, Gerard [0000-0003-4632-0213], Casey, Andrew [0000-0003-0174-0564], Worley, Clare [0000-0001-9310-2898], Apollo - University of Cambridge Repository, Thompson B.B., Few C.G., Bergemann M., Gibson B.K., MacFarlane B.A., Serenelli A., Gilmore G., Randich S., Vallenari A., Alfaro E.J., Bensby T., Francois P., Korn A.J., Bayo A., Carraro G., Casey A.R., Costado M.T., Donati P., Franciosini E., Frasca A., Hourihane A., Jofre P., Hill V., Heiter U., Koposov S.E., Lanzafame A., Lardo C., de Laverny P., Lewis J., Magrini L., Marconi G., Masseron T., Monaco L., Morbidelli L., Pancino E., Prisinzano L., Recio-Blanco A., Sacco G., Sousa S.G., Tautvaisiene G., Worley C.C., and Zaggia S.
Subjects: Matching (statistics), Milky Way, astro-ph.GA, FOS: Physical sciences, Scale (descriptive set theory), Astrophysics, F500, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, methods: numerical, 0103 physical sciences, galaxies: formation, 010303 astronomy & astrophysics, Selection (genetic algorithm), Astrophysics::Galaxy Astrophysics, Physics, [PHYS]Physics [physics], numerical [Methods], 010308 nuclear & particles physics, galaxies: evolution - galaxies: formation, abundances [Galaxy], Astronomy and Astrophysics, Effective temperature, Surface gravity, evolution [Galaxies], Astrophysics - Astrophysics of Galaxies, formation [Galaxies], Galaxy, Galaxy: abundance, Galaxies: evolution, Galaxies: formation, Galaxy: abundances, Methods: numerical, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Survey data collection, methods: numerical - Galaxy: abundances, galaxies: evolution, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: The typical methodology for comparing simulated galaxies with observational surveys is usually to apply a spatial selection to the simulation to mimic the region of interest covered by a comparable observational survey sample. In this work, we compare this approach with a more sophisticated post-processing in which the observational uncertainties and selection effects (photometric, surface gravity and effective temperature) are taken into account. We compare a 'solar neighbourhood analogue' region in a model MilkyWay-like galaxy simulated with RAMSES-CH with fourth release Gaia-ESO survey data. We find that a simple spatial cut alone is insufficient and that the observational uncertainties must be accounted for in the comparison. This is particularly true when the scale of uncertainty is large compared to the dynamic range of the data, e.g. in our comparison, the [Mg/Fe] distribution is affected much more than the more accurately determined [Fe/H] distribution. Despite clear differences in the underlying distributions of elemental abundances between simulation and observation, incorporating scatter to our simulation results to mimic observational uncertainty produces reasonable agreement. The quite complete nature of the Gaia-ESO survey means that the selection function has minimal impact on the distribution of observed age and metal abundances but this would become increasingly more important for surveys with narrower selection functions.© 2017 The Author(s)., This is based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 188.B-3002 (the Gaia-ESO Public Spectroscopic Survey). We acknowledge the insightful comments and support provided by our colleagues Stefano Pasetto, Daisuke Kawata, Rob Thacker and Dimitris Stamatellos. We would thank the anonymous referee for a very constructive report of the work presented here. BBT acknowledges the support of STFC through its PhD Studentship Programme (ST/F007701/1). We also acknowledge the generous allocation of resources from the Partnership for Advanced Computing in Europe (PRACE) via the DEISA Extreme Computing Initiative (PRACE-3IP Project RI-312763 and PRACE-4IP Project 653838) and STFC's DiRAC Facility (COSMOS: Galactic Archaeology). CGF acknowledges funding from the European Research Council for the FP7 ERC starting grant project LOCALSTAR and the DiRAC Complexity system, operated by the University of Leicester IT Services, which forms part of the STFC DiRAC HPC Facility (www.dirac.ac.uk). This equipment is funded by BIS National E-Infrastructure capital grant ST/K000373/1 and STFC DiRAC Operations grant ST/K0003259/1. DiRAC is part of the National E-Infrastructure. Continued access to the University of Hull's High Performance Computing Facility ('viper'), the HPC facility at the University of Central Lancashire and the computational facilities at Saint Mary's University are likewise gratefully acknowledged. TB was funded by the project grant 'The New Milky Way' from the Knut and Alice Wallenberg Foundation. SGS acknowledges the support by Fundacao para a Ciencia e Tecnologia (FCT) (ref: UID/FIS/04434/2013 & PTDC/FIS-AST/7073/2014 & Investigador FCT contract of reference IF/00028/2014) through national funds and by FEDER through COMPETE2020 (ref: POCI-01-0145-FEDER-007672 & POCI-01-0145-FEDER-016880). UH acknowledges support from the Swedish National Space Board (SNSB/Rymdstyrelsen). The Gaia-ESO Survey data products have been processed by the Cambridge Astronomy Survey Unit (CASU) at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF/Osservatorio Astrofisico di Arcetri. These data have been obtained from the Gaia-ESO Survey Data Archive, prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell' Istruzione, dell' Universita' e della Ricerca (MIUR) in the form of the grant 'Premiale VLT 2012'. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. MTC acknowledge the financial support from the Spanish Ministerio de Economia y Competitividad, through grant AYA2013-40611-P. UH acknowledges support from the Swedish National Space Board (SNSB/Rymdstyrelsen). This work was supported by Sonderforschungsbereich SFB 881 'The Milky Way System' (subprojects A5, C9) of the German Research Foundation (DFG). This work benefited from discussions at GNASH workshop, Victoria supported by the National Science Foundation under Grant No. PHY-1430152 (JINA Center for the Evolution of the Elements). ARC is supported by Australian Research Council Grant DP160100637
Published: 2018

44. The Gaia-ESO Survey: Churning through the Milky Way

Author: Carmela Lardo, Sofia Feltzing, Vanessa Hill, Laura Magrini, Amelia Bayo, Gerard Gilmore, P. de Laverny, S. Mikolaitis, Paula Jofre, A. Hourihane, E. Franciosini, Michael R. Hayden, Alejandra Recio-Blanco, Elena Pancino, Georges Kordopatis, Thomas Bensby, E. Stonkute, G. G. Sacco, Sofia Randich, Karin Lind, Angela Bragaglia, M. T. Costado, L. Morbidelli, Maria Bergemann, Sergey E. Koposov, A. C. Lanzafame, Jack Lewis, Guillaume Guiglion, Tomaž Zwitter, Andrew R. Casey, Lorenzo Monaco, C. C. Worley, Agence Nationale de la Recherche (France), Knut and Alice Wallenberg Foundation, European Southern Observatory, Science and Technology Facilities Council (UK), European Research Council, Leverhulme Trust, Istituto Nazionale di Astrofisica, Ministero dell'Istruzione, dell'Università e della Ricerca, European Science Foundation, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Astronomy [Cambridge], University of Cambridge [UK] (CAM), INAF - Osservatorio Astronomico di Bologna (OABO), Istituto Nazionale di Astrofisica (INAF), Lund Observatory, Lund University [Lund], INAF - Osservatorio Astrofisico di Catania (OACT), Ecole Polytechnique Fédérale de Lausanne (EPFL), Max-Planck-Institut für Astrophysik (MPA), Max-Planck-Gesellschaft, Istituto Nazionale di Fisica Nucleare, Sezione di Milano (INFN), Istituto Nazionale di Fisica Nucleare (INFN), University of Ljubljana, Hayden M.R., Recio-Blanco A., De Laverny P., Mikolaitis S., Guiglion G., Hill V., Gilmore G., Randich S., Bayo A., Bensby T., Bergemann M., Bragaglia A., Casey A., Costado M., Feltzing S., Franciosini E., Hourihane A., Jofre P., Koposov S., Kordopatis G., Lanzafame A., Lardo C., Lewis J., Lind K., Magrini L., Monaco L., Morbidelli L., Pancino E., Sacco G., Stonkute E., Worley C.C., Zwitter T., Gilmore, Gerard [0000-0003-4632-0213], Worley, Clare [0000-0001-9310-2898], and Apollo - University of Cambridge Repository
Subjects: astro-ph.GA, Metallicity, Milky Way, FOS: Physical sciences, Context (language use), Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy: disk, Astronomi, astrofysik och kosmologi, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astronomy, Astrophysics and Cosmology, stellar content [Galaxy], Galaxy: structure, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Orbital elements, Physics, Galaxy: stellar content, 010308 nuclear & particles physics, Velocity dispersion, Astronomy and Astrophysics, kinematics and dynamics [Galaxy], Astrophysics - Astrophysics of Galaxies, Galaxy, Galaxy: kinematics and dynamics, Space and Planetary Science, Radial velocity, Stars, 13. Climate action, Astrophysics of Galaxies (astro-ph.GA), Galaxy: kinematics and dynamic, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], disk [Galaxy], structure [Galaxy]
Abstract: Context. There have been conflicting results with respect to the extent that radial migration has played in the evolution of the Galaxy. Additionally, observations of the solar neighborhood have shown evidence of a merger in the past history of the Milky Way that drives enhanced radial migration. Aims. We attempt to determine the relative fraction of stars that have undergone significant radial migration by studying the orbital properties of metal-rich ([Fe/H] > 0.1) stars within 2 kpc of the Sun. We also aim to investigate the kinematic properties, such as velocity dispersion and orbital parameters, of stellar populations near the Sun as a function of [Mg/Fe] and [Fe/H], which could show evidence of a major merger in the past history of the Milky Way. Methods. We used a sample of more than 3000 stars selected from the fourth internal data release of the Gaia-ESO Survey. We used the stellar parameters from the Gaia-ESO Survey along with proper motions from PPMXL to determine distances, kinematics, and orbital properties for these stars to analyze the chemodynamic properties of stellar populations near the Sun. Results. Analyzing the kinematics of the most metal-rich stars ([Fe/H] > 0.1), we find that more than half have small eccentricities (e< 0.2) or are on nearly circular orbits. Slightly more than 20% of the metal-rich stars have perigalacticons R> 7 kpc. We find that the highest [Mg/Fe], metal-poor populations have lower vertical and radial velocity dispersions compared to lower [Mg/Fe] populations of similar metallicity by ~10 km s. The median eccentricity increases linearly with [Mg/Fe] across all metallicities, while the perigalacticon decreases with increasing [Mg/Fe] for all metallicities. Finally, the most [Mg/Fe]-rich stars are found to have significant asymmetric drift and rotate more than 40 km s slower than stars with lower [Mg/Fe] ratios. Conclusions. While our results cannot constrain how far stars have migrated, we propose that migration processes are likely to have played an important role in the evolution of the Milky Way, with metal-rich stars migrating from the inner disk toward to solar neighborhood and past mergers potentially driving enhanced migration of older stellar populations in the disk.© ESO, 2018., The authors thank Ivan Minchev for a useful discussion and the anonymous referee for useful comments. M.R.H. and A.R.B. received financial support from ANR, reference 14-CE33-0014-01. S.F. and T.B. acknowledge support from the project grant >The New Milky Way> from the Knut and Alice Wallenberg Foundation. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under program ID 188.B-3002. These data products have been processed by the Cambridge Astronomy Survey Unit (CASU) at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF/Osservatorio Astrofisico di Arcetri. These data have been obtained from the Gaia-ESO Survey Data Archive, prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell' Istruzione, dell' Universita' e della Ricerca (MIUR) in the form of the grant >Premiale VLT 2012>. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. This research has made use of the SIMBAD database, operated at CDS, Strasbourg, France and NASA's Astrophysics Data System.
Published: 2018

45. The Gaia-ESO Survey: Low-α element stars in the Galactic bulge

Author: Gerry Gilmore, G. Carraro, Lorenzo Monaco, Carine Babusiaux, P. de Laverny, L. Morbidelli, V. Hill, C. Allende Prieto, Annie C. Robin, A. Bragaglia, Carmela Lardo, Simone Zaggia, A. Recio-Blanco, Paula Jofre, A. Rojas-Arriagada, M. Zoccali, Sofia Randich, J. G. Fernandez-Trincado, Šarūnas Mikolaitis, Emilio J. Alfaro, Agence Nationale de la Recherche (France), European Commission, European Research Council, Leverhulme Trust, Comisión Nacional de Investigación Científica y Tecnológica (Chile), Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), DIBIT, San Raffaele Scientific Institute, Recio-Blanco A., Rojas-Arriagada A., De Laverny P., Mikolaitis S., Hill V., Zoccali M., Fernandez-Trincado J.G., Robin A.C., Babusiaux C., Gilmore G., Randich S., Alfaro E., Allende Prieto C., Bragaglia A., Carraro G., Jofre P., Lardo C., Monaco L., Morbidelli L., and Zaggia S.
Subjects: Milky Way, bulge [Galaxy], FOS: Physical sciences, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy: bulge, Abundance (ecology), Bulge, 0103 physical sciences, stellar content [Galaxy], Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, Dwarf galaxy, Physics, Galaxy: stellar content, 010308 nuclear & particles physics, abundances [Galaxy], Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Accretion (astrophysics), Abundance of the chemical elements, Galaxy: abundance, Stars, Space and Planetary Science, Globular cluster, Astrophysics of Galaxies (astro-ph.GA), Galaxy: abundances, Astrophysics::Earth and Planetary Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: We take advantage of the Gaia-ESO Survey iDR4 bulge data to search for abundance anomalies that could shed light on the composite nature of the Milky Way bulge. The α-element (Mg, Si, and whenever available, Ca) abundances, and their trends with Fe abundances have been analysed for a total of 776 bulge stars. In addition, the aluminum abundances and their ratio to Fe and Mg have also been examined. Our analysis reveals the existence of low-α element abundance stars with respect to the standard bulge sequence in the [α/ Fe] versus [Fe/H] plane. Eighteen objects present deviations in [α/ Fe] ranging from 2.1 to 5.3σ with respect to the median standard value. Those stars do not show Mg-Al anti-correlation patterns. Incidentally, this sign of the existence of multiple stellar populations is reported firmly for the first time for the bulge globular cluster NGC 6522. The identified low-α abundance stars have chemical patterns that are compatible with those of the thin disc. Their link with massive dwarf galaxies accretion seems unlikely, as larger deviations in α abundance and Al would be expected. The vision of a bulge composite nature and a complex formation process is reinforced by our results. The approach used, which is a multi-method and model-driven analysis of high resolution data, seems crucial to reveal this complexity. © ESO, 2017., A.R.B., P.d.L., and V.H. acknowledge financial support form the ANR 14-CE33-014-01. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR) in the form of the grant "Premiale VLT 2012". The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. M. Zoccali gratefully acknowledge support by the Ministry of Economy, Development, and Tourism's Millenium Science Initiative through grant IC120009, awarded to the Millenium Institute of Astrophysics (MAS), by Fondecyt Regular 1150345 and by the BASAL-CATA Center for Astrophysics and Associated Technologies PFB-06.
Published: 2017

46. The RAVE-on Catalog of Stellar Atmospheric Parameters and Chemical Abundances for Chemo-dynamic Studies in the Gaia Era

Author: Georges Kordopatis, Gerry Gilmore, Ulisse Munari, Olivier Bienaymé, Julio F. Navarro, Hans Walter-Rix, Harry Enke, Andrea Kunder, Matthias Steinmetz, Eva K. Grebel, Jason L. Sanders, Keith Hawkins, Arnaud Siebert, George M. Seabroke, Warren Reid, Rosemary F. G. Wyse, Sergey E. Koposov, Andrew R. Casey, David W. Hogg, Kenneth C. Freeman, Gal Matijevic, Amina Helmi, Brad K. Gibson, Melissa Ness, Luca Casagrande, Joss Bland-Hawthorn, Tomaž Zwitter, Astronomy, Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Casey, AR [0000-0003-0174-0564], Hogg, DW [0000-0003-2866-9403], Rix, HW [0000-0003-4996-9069], Kunder, A [0000-0002-2808-1370], Steinmetz, M [0000-0001-6516-7459], Koposov, S [0000-0003-2644-135X], Sanders, J [0000-0003-4593-6788], Gilmore, G [0000-0003-4632-0213], Zwitter, T [0000-0002-2325-8763], Bland-Hawthorn, J [0000-0001-7516-4016], Gibson, BK [0000-0003-4446-3130], Grebel, EK [0000-0002-1891-3794], Helmi, A [0000-0003-3937-7641], Munari, U [0000-0001-6805-9664], and Apollo - University of Cambridge Repository
Subjects: SOLAR NEIGHBORHOOD, astro-ph.SR, stars: abundances, METAL-POOR STARS, Milky Way, astro-ph.GA, FOS: Physical sciences, Astrophysics, 01 natural sciences, 7. Clean energy, Spectral line, G-DWARF, GLOBULAR-CLUSTERS, 0103 physical sciences, Galaxy formation and evolution, RESOLUTION SPECTROSCOPY, VELOCITY EXPERIMENT RAVE, Spectroscopy, 010303 astronomy & astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), ComputingMilieux_MISCELLANEOUS, Physics, 010308 nuclear & particles physics, Astronomy and Astrophysics, ELEMENTAL ABUNDANCE, Effective temperature, Surface gravity, Astrophysics - Astrophysics of Galaxies, Radial velocity, 1ST DATA RELEASE, Stars, GENEVA-COPENHAGEN SURVEY, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Astrophysics of Galaxies (astro-ph.GA), MILKY-WAY, stars: fundamental parameters
Abstract: The orbits, atmospheric parameters, chemical abundances, and ages of individual stars in the Milky Way provide the most comprehensive illustration of galaxy formation available. The Tycho-Gaia Astrometric Solution (TGAS) will deliver astrometric parameters for the largest ever sample of Milky Way stars, though its full potential cannot be realized without the addition of complementary spectroscopy. Among existing spectroscopic surveys, the RAdial Velocity Experiment (RAVE) has the largest overlap with TGAS ($\gtrsim$200,000 stars). We present a data-driven re-analysis of 520,781 RAVE spectra using The Cannon. For red giants, we build our model using high-fidelity APOGEE stellar parameters and abundances for stars that overlap with RAVE. For main-sequence and sub-giant stars, our model uses stellar parameters from the K2/EPIC. We derive and validate effective temperature $T_{\rm eff}$, surface gravity $\log{g}$, and chemical abundances of up to seven elements (O, Mg, Al, Si, Ca, Fe, Ni). We report a total of 1,685,851 elemental abundances with a typical precision of 0.07 dex, a substantial improvement over previous RAVE data releases. The synthesis of RAVE-on and TGAS is the most powerful data set for chemo-dynamic analyses of the Milky Way ever produced., Derived labels, associated errors, and relevant metadata are available from the RAVE database (http://www.rave-survey.org) from 19 September 2016
Published: 2017

47. PLATO as it is: a legacy mission for Galactic archaeology

Author: A. Miglio, C. Chiappini, B. Mosser, G. R. Davies, K. Freeman, L. Girardi, P. Jofré, D. Kawata, B. M. Rendle, M. Valentini, L. Casagrande, W. J. Chaplin, G. Gilmore, K. Hawkins, B. Holl, T. Appourchaux, K. Belkacem, D. Bossini, K. Brogaard, M.‐J. Goupil, J. Montalbán, A. Noels, F. Anders, T. Rodrigues, G. Piotto, D. Pollacco, H. Rauer, C. Allende Prieto, P. P. Avelino, C. Babusiaux, C. Barban, B. Barbuy, S. Basu, F. Baudin, O. Benomar, O. Bienaymé, J. Binney, J. Bland‐Hawthorn, A. Bressan, C. Cacciari, T. L. Campante, S. Cassisi, J. Christensen‐Dalsgaard, F. Combes, O. Creevey, M. S. Cunha, R. S. Jong, P. Laverny, S. Degl'Innocenti, S. Deheuvels, É. Depagne, J. Ridder, P. Di Matteo, M. P. Di Mauro, M.‐A. Dupret, P. Eggenberger, Y. Elsworth, B. Famaey, S. Feltzing, R. A. García, O. Gerhard, B. K. Gibson, L. Gizon, M. Haywood, R. Handberg, U. Heiter, S. Hekker, D. Huber, R. Ibata, D. Katz, S. D. Kawaler, H. Kjeldsen, D. W. Kurtz, N. Lagarde, Y. Lebreton, M. N. Lund, S. R. Majewski, P. Marigo, M. Martig, S. Mathur, I. Minchev, T. Morel, S. Ortolani, M. H. Pinsonneault, B. Plez, P. G. Prada Moroni, D. Pricopi, A. Recio‐Blanco, C. Reylé, A. Robin, I. W. Roxburgh, M. Salaris, B. X. Santiago, R. Schiavon, A. Serenelli, S. Sharma, V. Silva Aguirre, C. Soubiran, M. Steinmetz, D. Stello, K. G. Strassmeier, P. Ventura, R. Ventura, N. A. Walton, C. C. Worley, Institut d'Astrophysique et de Géophysique [Liège], Université de Liège, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Arizona State University [Tempe] (ASU), Leibniz-Institut für Astrophysik Potsdam (AIP), Department of Physics and Astronomy [Aarhus], Aarhus University [Aarhus], School of Physics and Astronomy [Birmingham], University of Birmingham [Birmingham], Heckscher-Klinikum, Danish AsteroSeismology Centre (DASC), Universidade Federal de São Paulo (UNIFESP), DLR Institut für Planetenforschung, Deutsches Zentrum für Luft- und Raumfahrt [Berlin] (DLR), Department of Astronomy [New Haven], Yale University [New Haven], Evolution et Modélisation des Bassins Sédimentaires (EMBS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Department of Biomedical, Metabolic and Neural Sciences [Modena], Chaire Galaxies et cosmologie, Collège de France (CdF (institution)), Institut d'astrophysique spatiale (IAS), Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universidade de Aveiro, Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de recherche en astrophysique et planétologie (IRAP), Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Las Cumbres Observatory (LCO), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Université de Strasbourg (UNISTRA), Observatoire astronomique de Strasbourg (ObAS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universitat de Girona (UdG), Max-Planck-Institut für Extraterrestrische Physik (MPE), Max-Planck-Institut für Sonnensystemforschung (MPS), Max-Planck-Gesellschaft, SETI Institute, University of Illinois at Urbana Champaign (UIUC), University of Illinois at Urbana-Champaign [Urbana], University of Illinois System-University of Illinois System, Universidade Federal de Santa Catarina = Federal University of Santa Catarina [Florianópolis] (UFSC), Univers, Transport, Interfaces, Nanostructures, Atmosphère et environnement, Molécules (UMR 6213) (UTINAM), Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Institut de Physique de Rennes (IPR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Centre National de la Recherche Scientifique (CNRS), Space Science Institute [Boulder] (SSI), Department of Astronomy (Ohio State University), Ohio State University [Columbus] (OSU), Laboratoire Univers et Particules de Montpellier (LUPM), Université Montpellier 2 - Sciences et Techniques (UM2)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Astrophysical Research Institute [Liverpool], Liverpool John Moore University (ljmu), Institute of Space Sciences [Barcelona] (ICE-CSIC), Spanish National Research Council [Madrid] (CSIC), Sydney Institute for Astronomy (SIfA), The University of Sydney, M2A 2017, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leibniz Institute for Astrophysics Potsdam (AIP), Symbiose Marine (SM), Evolution Paris Seine, Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS), DNRF106, The Danish National Research Foundation, Centre National d’Etudes Spatiales, PRIN INAF 2014 - CRA 1.05.01.94.05, Science and Technology Facilities Council, Programme National Cosmologie et Galaxies (CNRS/INSU, France), IF/00894/2012/, Federación Española de Enfermedades Raras, CNES Fellowship, 615604, ERC Consolidator (STARKEY), Federaal Wetenschapsbeleid, ESP2015-66134-R, Ministerio de Economía y Competitividad, European Commission's Seventh Framework Programme, Swedish National Space Board, European Commission, DLR, FT1400147, Australian Research Council, NNX16AI09G, National Aeronautics and Space Administration, European Cooperation in Science and Technology, CH1188/2-1, DFG, CA16117, ChETEC COST Action, 10118, Villum Fonden, European Union FP7 program, 320360, ERC, UID/FIS/04434/2013, FCT, G1502, NYUAD Institute, Programme National de Physique Stellaire (PNPS), ITA, USA, GBR, FRA, DEU, ESP, Federal University of Sao Paulo (Unifesp), Université Paris-Saclay, Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Collège de France - Chaire Galaxies et cosmologie, Université Paris-Sud - Paris 11 (UP11)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Université de Genève = University of Geneva (UNIGE), Max-Planck-Institut für Sonnensystemforschung = Max Planck Institute for Solar System Research (MPS), Galaxies, Etoiles, Physique, Instrumentation (GEPI), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, University of Illinois System, Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC), Université de Rennes (UR)-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), Miglio A., Chiappini C., Mosser B., Davies G.R., Freeman K., Girardi L., Jofre P., Kawata D., Rendle B.M., Valentini M., Casagrande L., Chaplin W.J., Gilmore G., Hawkins K., Holl B., Appourchaux T., Belkacem K., Bossini D., Brogaard K., Goupil M.-J., Montalban J., Noels A., Anders F., Rodrigues T., Piotto G., Pollacco D., Rauer H., Prieto C.A., Avelino P.P., Babusiaux C., Barban C., Barbuy B., Basu S., Baudin F., Benomar O., Bienayme O., Binney J., Bland-Hawthorn J., Bressan A., Cacciari C., Campante T.L., Cassisi S., Christensen-Dalsgaard J., Combes F., Creevey O., Cunha M.S., Jong R.S., Laverny P., Degl'Innocenti S., Deheuvels S., Depagne E., Ridder J., Matteo P.D., Mauro M.P.D., Dupret M.-A., Eggenberger P., Elsworth Y., Famaey B., Feltzing S., Garcia R.A., Gerhard O., Gibson B.K., Gizon L., Haywood M., Handberg R., Heiter U., Hekker S., Huber D., Ibata R., Katz D., Kawaler S.D., Kjeldsen H., Kurtz D.W., Lagarde N., Lebreton Y., Lund M.N., Majewski S.R., Marigo P., Martig M., Mathur S., Minchev I., Morel T., Ortolani S., Pinsonneault M.H., Plez B., Moroni P.G.P., Pricopi D., Recio-Blanco A., Reyle C., Robin A., Roxburgh I.W., Salaris M., Santiago B.X., Schiavon R., Serenelli A., Sharma S., Aguirre V.S., Soubiran C., Steinmetz M., Stello D., Strassmeier K.G., Ventura P., Ventura R., Walton N.A., Worley C.C., Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Montpellier 2 - Sciences et Techniques (UM2), Université Nice Sophia Antipolis (... - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles et de la Guyane (UAG)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: RED-GIANT STARS, Astrophysics, 01 natural sciences, COROT ASTEROSEISMOLOGY FIELDS, Astrophysics::Solar and Stellar Astrophysics, VELOCITY EXPERIMENT RAVE, Galaxy: structure, 010303 astronomy & astrophysics, SUN-LIKE STAR, QC, QB, Physics, structure - stars: abundances - stars: fundamental parameters - stars: oscillations - surveys [Galaxy], Astrophysics - Solar and Stellar Astrophysics, stars: fundamental parameters, stars: oscillations, Astrophysics::Earth and Planetary Astrophysics, SOLAR-LIKE OSCILLATIONS, THICK DISK, stars: abundances, Relation (database), DATA RELEASE, Milky Way, surveys, Astronomy and Astrophysics, Space and Planetary Science, FOS: Physical sciences, MILKY-WAY DISK, F500, Kepler, Asteroseismology, ATMOSPHERIC PARAMETERS, Settore FIS/05 - Astronomia e Astrofisica, 0103 physical sciences, Quality (philosophy), Galaxy: structure â stars: abundances â stars: fundamental parameters â stars: oscillations â surveys, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 010308 nuclear & particles physics, Galaxy: structure – stars: abundances – stars: fundamental parameters – stars: oscillations – surveys, [PHYS.ASTR.SR]Physics [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Data science, Astrophysics - Astrophysics of Galaxies, Galaxy, COLD DARK-MATTER, Stars, Astrophysics of Galaxies (astro-ph.GA), Stellar physics, Galaxy: structure â stars: abundances â stars: fundamental parameters â stars: oscillations â surveys, Galaxy: structure - stars: abundances - stars: fundamental parameters - stars: oscillations - surveys
Abstract: Deciphering the assembly history of the Milky Way is a formidable task, which becomes possible only if one can produce high-resolution chrono-chemo-kinematical maps of the Galaxy. Data from large-scale astrometric and spectroscopic surveys will soon provide us with a well-defined view of the current chemo-kinematical structure of the Milky Way, but will only enable a blurred view on the temporal sequence that led to the present-day Galaxy. As demonstrated by the (ongoing) exploitation of data from the pioneering photometric missions CoRoT, Kepler, and K2, asteroseismology provides the way forward: solar-like oscillating giants are excellent evolutionary clocks thanks to the availability of seismic constraints on their mass and to the tight age-initial-mass relation they adhere to. In this paper we identify five key outstanding questions relating to the formation and evolution of the Milky Way that will need precise and accurate ages for large samples of stars to be addressed, and we identify the requirements in terms of number of targets and the precision on the stellar properties that are needed to tackle such questions. By quantifying the asteroseismic yields expected from PLATO for red-giant stars, we demonstrate that these requirements are within the capabilities of the current instrument design, provided that observations are sufficiently long to identify the evolutionary state and allow robust and precise determination of acoustic-mode frequencies. This will allow us to harvest data of sufficient quality to reach a 10% precision in age. This is a fundamental pre-requisite to then reach the more ambitious goal of a similar level of accuracy, which will only be possible if we have to hand a careful appraisal of systematic uncertainties on age deriving from our limited understanding of stellar physics, a goal which conveniently falls within the main aims of PLATO's core science., 17 pages, 9 figures, accepted for publication in Astronomical Notes
Published: 2017

48. The Gaia-ESO Survey: the selection function of the Milky Way field stars

Author: Rodolfo Smiljanic, Luca Sbordone, Carmela Lardo, G. Ruchti, A. C. Lanzafame, Sofia Feltzing, Elena Pancino, L. Morbidelli, Sergey E. Koposov, Gerard Gilmore, Georges Kordopatis, Thomas Bensby, Tomaž Zwitter, E. Stonkute, Andrew R. Casey, James R. Lewis, Sofia Randich, Clare Worley, G. G. Sacco, L. M. Howes, Lorenzo Monaco, Laura Magrini, M. T. Costado, Angela Bragaglia, E. Franciosini, A. Hourihane, Paula Jofre, Grazina Tautvaisiene, Andreas Korn, Stonkute E., Koposov S.E., Howes L.M., Feltzing S., Worley C.C., Gilmore G., Ruchti G.R., Kordopatis G., Randich S., Zwitter T., Bensby T., Bragaglia A., Smiljanic R., Costado M.T., Tautvaisiene G., Casey A.R., Korn A.J., Lanzafame A.C., Pancino E., Franciosini E., Hourihane A., Jofre P., Lardo C., Lewis J., Magrini L., Monaco L., Morbidelli L., Sacco G.G., Sbordone L., Koposov, Sergey [0000-0003-2644-135X], Worley, Clare [0000-0001-9310-2898], Gilmore, Gerard [0000-0003-4632-0213], Casey, Andrew [0000-0003-0174-0564], and Apollo - University of Cambridge Repository
Subjects: Galactic astronomy, astro-ph.GA, Milky Way, Techniques: spectroscopic, FOS: Physical sciences, Star count, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Surveys, 01 natural sciences, evolution [Galaxy], surveys, Bulge, spectroscopi [Techniques], 0103 physical sciences, Galaxy formation and evolution, Survey, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Selection (genetic algorithm), QC, Astrophysics::Galaxy Astrophysics, QB, Physics, Galaxy: evolution, Very Large Telescope, general [Stars], 010308 nuclear & particles physics, techniques: spectroscopic, surveys, stars: general, Galaxy: evolution, Astronomy, Astronomy and Astrophysics, Astrophysics - Astrophysics of Galaxies, Stars, 13. Climate action, Space and Planetary Science, Stars: general, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, astro-ph.IM
Abstract: The Gaia-ESO Survey was designed to target all major Galactic components (i.e., bulge, thin and thick discs, halo and clusters), with the goal of constraining the chemical and dynamical evolution of the Milky Way. This paper presents the methodology and considerations that drive the selection of the targeted, allocated and successfully observed Milky Way field stars. The detailed understanding of the survey construction, specifically the influence of target selection criteria on observed Milky Way field stars is required in order to analyse and interpret the survey data correctly. We present the target selection process for the Milky Way field stars observed with VLT/FLAMES and provide the weights that characterise the survey target selection. The weights can be used to account for the selection effects in the Gaia-ESO Survey data for scientific studies. We provide a couple of simple examples to highlight the necessity of including such information in studies of the stellar populations in the Milky Way., ES, LH, SF, GRR and TB acknowledge support from the project grant ‘The New Milky Way’ from the Knut and Alice Wallenberg Foundation. RS acknowledges support from NCN/Poland through grant 2014/15/B/ST9/03981. AJK acknowledges support by the Swedish National Space Board. Based on data products from observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 188.B-3002. These data products have been processed by the CASU at the Institute of Astronomy, University of Cambridge, and by the FLAMES/UVES reduction team at INAF/Osservatorio Astrofisico di Arcetri. These data have been obtained from the GaiaESO Survey Data Archive, prepared and hosted by the Wide Field Astronomy Unit, Institute for Astronomy, University of Edinburgh, which is funded by the UK Science and Technology Facilities Council. This work was partly supported by the European Union FP7 programme through ERC grant number 320360 and by the Leverhulme Trust through grant RPG-2012-541. We acknowledge the support from INAF and Ministero dell’ Istruzione, dell’ Universita’` e della Ricerca (MIUR) in the form of the grant ‘Premiale VLT 2012’. The results presented here benefit from discussions held during the Gaia-ESO workshops and conferences supported by the ESF (European Science Foundation) through the GREAT Research Network Programme. Based on observations obtained as part of the VHS, ESO Program, 179.A-2010 (PI: McMahon). Funding for SDSS-III has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, and the US Department of Energy Office of Science., This is the final version of the article. It first appeared from Oxford University Press via http://dx.doi.org/10.1093/mnras/stw1011
Published: 2016

49. Gaia FGK benchmark stars: abundances of α and iron-peak elements

Author: Rosanna Sordo, Caroline Soubiran, A. Hourihane, Tristan Cantat-Gaudin, Elena Pancino, Alejandra Recio-Blanco, Carmela Lardo, L. Chemin, J. I. González Hernández, Gerry Gilmore, Ulrike Heiter, S. G. Sousa, Vardan Adibekyan, Elisa Delgado-Mena, Šarūnas Mikolaitis, S. Blanco-Cuaresma, Guillaume Guiglion, D. Montes, Maria Bergemann, Hugo M. Tabernero, Thomas Masseron, S. Van Eck, Antonella Vallenari, P. de Laverny, Clare Worley, Karin Lind, Paula Jofre, Thomas Nordlander, Laura Magrini, M2A 2015, Laboratoire d'Astrophysique de Bordeaux [Pessac] (LAB), Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Bordeaux (UB)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Observatoire Astronomique de l'Université de Genève (ObsGE), Université de Genève (UNIGE), Institut d'Astronomie et d'Astrophysique, Université libre de Bruxelles (ULB), Jofre P., Heiter U., Soubiran C., Blanco-Cuaresma S., Masseron T., Nordlander T., Chemin L., Worley C.C., Van Eck S., Hourihane A., Gilmore G., Adibekyan V., Bergemann M., Cantat-Gaudin T., Delgado-Mena E., Gonzalez Hernandez J.I., Guiglion G., Lardo C., De Laverny P., Lind K., Magrini L., Mikolaitis S., Montes D., Pancino E., Recio-Blanco A., Sordo R., Sousa S., Tabernero H.M., and Vallenari A.
Subjects: Astrofísica, Milky Way, FOS: Physical sciences, Astrophysics, Spectral line, Astronomi, astrofysik och kosmologi, Abundance (ecology), stars: atmospheres, data analysis [methods], Calibration, Astronomy, Astrophysics and Cosmology, Astrophysics::Solar and Stellar Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, QC, QB, atmospheres [stars], Physics, abundances [Galaxy], Astronomy and Astrophysics, Iron peak, methods: data analysis, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Galaxy: abundance, Astronomía, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Homogeneous, Benchmark (computing), Galaxy: abundances, Astrophysics::Earth and Planetary Astrophysics, Methods: data analysi
Abstract: In the current era of large spectroscopic surveys of the Milky Way, reference stars for calibrating astrophysical parameters and chemical abundances are of paramount importance. We determine elemental abundances of Mg, Si, Ca, Sc, Ti, V, Cr, Mn, Co and Ni for our predefined set of Gaia FGK benchmark stars. By analysing high-resolution and high-signal to noise spectra taken from several archive datasets, we combined results of eight different methods to determine abundances on a line-by-line basis. We perform a detailed homogeneous analysis of the systematic uncertainties, such as differential versus absolute abundance analysis, as well as we assess errors due to NLTE and the stellar parameters in our final abundances. Our results are provided by listing final abundances and the different sources of uncertainties, as well as line-by-line and method-by-method abundances. The Gaia FGK benchmark stars atmospheric parameters are already being widely used for calibration of several pipelines applied to different surveys. With the added reference abundances of 10 elements this set is very suitable to calibrate the chemical abundances obtained by these pipelines., Comment: Accepted for publication in A&A, Printer format: 65 pages, 18 figures, 25 tables
Published: 2015

50. The Gaia-ESO Survey: New constraints on the Galactic disc velocity dispersion and its chemical dependencies

Author: Jack Lewis, A. Hourihane, Sofia Randich, Karin Lind, Paula Jofre, Ivan Minchev, E. Franciosini, S. Mikolaitis, Gerard Gilmore, R. F. G. Wyse, Laura Magrini, M. T. Costado, G. G. Sacco, L. Morbidelli, Gregory R. Ruchti, Vanessa Hill, Cristina Chiappini, P. de Laverny, Clare Worley, Alejandra Recio-Blanco, Elena Pancino, Carmela Lardo, Sofia Feltzing, Thomas Bensby, Georges Kordopatis, Ettore Flaccomio, Guillaume Guiglion, Simone Zaggia, Amelia Bayo, Sergey E. Koposov, Guiglion G., Recio-Blanco A., De Laverny P., Kordopatis G., Hill V., Mikolaitis S., Minchev I., Chiappini C., Wyse R.F.G., Gilmore G., Randich S., Feltzing S., Bensby T., Flaccomio E., Koposov S.E., Pancino E., Bayo A., Costado M.T., Franciosini E., Hourihane A., Jofre P., Lardo C., Lewis J., Lind K., Magrini L., Morbidelli L., Sacco G.G., Ruchti G., Worley C.C., and Zaggia S.
Subjects: 010504 meteorology & atmospheric sciences, Metallicity, Milky Way, astro-ph.GA, FOS: Physical sciences, Kinematics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Galaxy: disk, Astronomi, astrofysik och kosmologi, 0103 physical sciences, stellar content [Galaxy], Astronomy, Astrophysics and Cosmology, Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, Spectrograph, QC, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, QB, Physics, Galaxy: stellar content, Turbulence, Stars: abundances, Velocity dispersion, abundances [Galaxy], Astronomy and Astrophysics, kinematics and dynamics [Galaxy], Astrophysics - Astrophysics of Galaxies, abundances [stars], Galaxy: abundance, Stars, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), Galaxy: kinematics and dynamic, Astrophysics::Earth and Planetary Astrophysics, Data release, disk [Galaxy]
Abstract: Understanding the history and the evolution of the Milky Way disc is one of the main goals of modern astrophysics. We study the velocity dispersion behaviour of Galactic disc stars as a function of the [Mg/Fe] ratio, which can be used as a proxy of relative age. This key relation is essential to constrain the formation mechanisms of the disc stellar populations as well as the cooling processes. We used the recommended parameters and chemical abundances of 7800 FGK Milky Way field stars from the second internal data release of the Gaia-ESO Survey. These stars were observed with the GIRAFFE spectrograph, and cover a large spatial volume (6+0.2dex. First, the velocity dispersion increases with [Mg/Fe] at all [Fe/H] ratios for the thin-disc stars, and then it decreases for the thick-disc at the highest [Mg/Fe] abundances. Similar trends are observed within the errors for the azimuthal velocity dispersion, while a continuous increase with [Mg/Fe] is observed for the vertical velocity dispersion. The velocity dispersion decrease agrees with previous measurements of the RAVE survey, although it is observed here for a greater metallicity interval and a larger spatial volume. We confirm the existence of [Mg/Fe]-rich thick-disc stars with cool kinematics in the generally turbulent context of the primitive Galactic disc. This is discussed in the framework of the different disc formation scenarios., Comment: 14 pages, 13 figures, A&A accepted
Published: 2015

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