@article{3069388,
    title = "Gaia Data Release 1: Testing parallaxes with local Cepheids and RR Lyrae stars",
    author = "Clementini, G. and Eyer, L. and Ripepi, V. and Marconi, M. and Muraveva, T. and Garofalo, A. and Sarro, L.M. and Palmer, M. and Luri, X. and Molinaro, R. and Rimoldini, L. and Szabados, L. and Musella, I. and Anderson, R.I. and Prusti, T. and De Bruijne, J.H.J. and Brown, A.G.A. and Vallenari, A. and Babusiaux, C. and Bailer-Jones, C.A.L. and Bastian, U. and Biermann, M. and Evans, D.W. and Jansen, F. and Jordi, C. and Klioner, S.A. and Lammers, U. and Lindegren, L. and Mignard, F. and Panem, C. and Pourbaix, D. and Randich, S. and Sartoretti, P. and Siddiqui, H.I. and Soubiran, C. and Valette, V. and Van Leeuwen, F. and Walton, N.A. and Aerts, C. and Arenou, F. and Cropper, M. and Drimmel, R. and Høg, E. and Katz, D. and Lattanzi, M.G. and O'Mullane, W. and Grebel, E.K. and Holland, A.D. and Huc, C. and Passot, X. and Perryman, M. and Bramante, L. and Cacciari, C. and Castañeda, J. and Chaoul, L. and Cheek, N. and De Angeli, F. and Fabricius, C. and Guerra, R. and Hernández, J. and Jean-Antoine-Piccolo, A. and Masana, E. and Messineo, R. and Mowlavi, N. and Nienartowicz, K. and Ordóñez-Blanco, D. and Panuzzo, P. and Portell, J. and Richards, P.J. and Riello, M. and Seabroke, G.M. and Tanga, P. and Thévenin, F. and Torra, J. and Els, S.G. and Gracia-Abril, G. and Comoretto, G. and Garcia-Reinaldos, M. and Lock, T. and Mercier, E. and Altmann, M. and Andrae, R. and Astraatmadja, T.L. and Bellas-Velidis, I. and Benson, K. and Berthier, J. and Blomme, R. and Busso, G. and Carry, B. and Cellino, A. and Cowell, S. and Creevey, O. and Cuypers, J. and Davidson, M. and De Ridder, J. and De Torres, A. and Delchambre, L. and Dell'Oro, A. and Ducourant, C. and Frémat, Y. and García-Torres, M. and Gosset, E. and Halbwachs, J.-L. and Hambly, N.C. and Harrison, D.L. and Hauser, M. and Hestroffer, D. and Hodgkin, S.T. and Huckle, H.E. and Hutton, A. and Jasniewicz, G. and Jordan, S. and Kontizas, M. and Korn, A.J. and Lanzafame, A.C. and Manteiga, M. and Moitinho, A. and Muinonen, K. and Osinde, J. and Pancino, E. and Pauwels, T. and Petit, J.-M. and Recio-Blanco, A. and Robin, A.C. and Siopis, C. and Smith, M. and Smith, K.W. and Sozzetti, A. and Thuillot, W. and Van Reeven, W. and Viala, Y. and Abbas, U. and Abreu Aramburu, A. and Accart, S. and Aguado, J.J. and Allan, P.M. and Allasia, W. and Altavilla, G. and Álvarez, M.A. and Alves, J. and Andrei, A.H. and Anglada Varela, E. and Antiche, E. and Antoja, T. and Antón, S. and Arcay, B. and Bach, N. and Baker, S.G. and Balaguer-Núñez, L. and Barache, C. and Barata, C. and Barbier, A. and Barblan, F. and Barrado, N.Y. and Barros, M. and Barstow, M.A. and Becciani, U. and Bellazzini, M. and Bello García, A. and Belokurov, V. and Bendjoya, P. and Berihuete, A. and Bianchi, L. and Bienaymé, O. and Billebaud, F. and Blagorodnova, N. and Blanco-Cuaresma, S. and Boch, T. and Bombrun, A. and Borrachero, R. and Bouquillon, S. and Bourda, G. and Bragaglia, A. and Breddels, M.A. and Brouillet, N. and Brüsemeister, T. and Bucciarelli, B. and Burgess, P. and Burgon, R. and Burlacu, A. and Busonero, D. and Buzzi, R. and Caffau, E. and Cambras, J. and Campbell, H. and Cancelliere, R. and Cantat-Gaudin, T. and Carlucci, T. and Carrasco, J.M. and Castellani, M. and Charlot, P. and Charnas, J. and Chiavassa, A. and Clotet, M. and Cocozza, G. and Collins, R.S. and Costigan, G. and Crifo, F. and Cross, N.J.G. and Crosta, M. and Crowley, C. and Dafonte, C. and Damerdji, Y. and Dapergolas, A. and David, P. and David, M. and De Cat, P. and De Felice, F. and De Laverny, P. and De Luise, F. and De March, R. and De Souza, R. and Debosscher, J. and Del Pozo, E. and Delbo, M. and Delgado, A. and Delgado, H.E. and Di Matteo, P. and Diakite, S. and Distefano, E. and Dolding, C. and Dos Anjos, S. and Drazinos, P. and Durán, J. and Dzigan, Y. and Edvardsson, B. and Enke, H. and Evans, N.W. and Eynard Bontemps, G. and Fabre, C. and Fabrizio, M. and Falcão, A.J. and Farràs Casas, M. and Federici, L. and Fedorets, G. and Fernández-Hernández, J. and Fernique, P. and Fienga, A. and Figueras, F. and Filippi, F. and Findeisen, K. and Fonti, A. and Fouesneau, M. and Fraile, E. and Fraser, M. and Fuchs, J. and Gai, M. and Galleti, S. and Galluccio, L. and Garabato, D. and García-Sedano, F. and Garralda, N. and Gavras, P. and Gerssen, J. and Geyer, R. and Gilmore, G. and Girona, S. and Giuffrida, G. and Gomes, M. and González-Marcos, A. and González-Núñez, J. and González-Vidal, J.J. and Granvik, M. and Guerrier, A. and Guillout, P. and Guiraud, J. and Gúrpide, A. and Gutiérrez-Sánchez, R. and Guy, L.P. and Haigron, R. and Hatzidimitriou, D. and Haywood, M. and Heiter, U. and Helmi, A. and Hobbs, D. and Hofmann, W. and Holl, B. and Holland, G. and Hunt, J.A.S. and Hypki, A. and Icardi, V. and Irwin, M. and Jevardat De Fombelle, G. and Jofré, P. and Jonker, P.G. and Jorissen, A. and Julbe, F. and Karampelas, A. and Kochoska, A. and Kohley, R. and Kolenberg, K. and Kontizas, E. and Koposov, S.E. and Kordopatis, G. and Koubsky, P. and Krone-Martins, A. and Kudryashova, M. and Bachchan, R.K. and Lacoste-Seris, F. and Lanza, A.F. and Lavigne, J.-B. and Le Poncin-Lafitte, C. and Lebreton, Y. and Lebzelter, T. and Leccia, S. and Leclerc, N. and Lecoeur-Taibi, I. and Lemaitre, V. and Lenhardt, H. and Leroux, F. and Liao, S. and Licata, E. and Lindstrøm, H.E.P. and Lister, T.A. and Livanou, E. and Lobel, A. and Löffler, W. and López, M. and Lorenz, D. and Macdonald, I. and Magalhães Fernandes, T. and Managau, S. and Mann, R.G. and Mantelet, G. and Marchal, O. and Marchant, J.M. and Marinoni, S. and Marrese, P.M. and Marschalkó, G. and Marshall, D.J. and Martín-Fleitas, J.M. and Martino, M. and Mary, N. and Matijevič, G. and McMillan, P.J. and Messina, S. and Michalik, D. and Millar, N.R. and Miranda, B.M.H. and Molina, D. and Molinaro, M. and Molnár, L. and Moniez, M. and Montegriffo, P. and Mor, R. and Mora, A. and Morbidelli, R. and Morel, T. and Morgenthaler, S. and Morris, D. and Mulone, A.F. and Narbonne, J. and Nelemans, G. and Nicastro, L. and Noval, L. and Ordénovic, C. and Ordieres-Meré, J. and Osborne, P. and Pagani, C. and Pagano, I. and Pailler, F. and Palacin, H. and Palaversa, L. and Parsons, P. and Pecoraro, M. and Pedrosa, R. and Pentikäinen, H. and Pichon, B. and Piersimoni, A.M. and Pineau, F.-X. and Plachy, E. and Plum, G. and Poujoulet, E. and Prša, A. and Pulone, L. and Ragaini, S. and Rago, S. and Rambaux, N. and Ramos-Lerate, M. and Ranalli, P. and Rauw, G. and Read, A. and Regibo, S. and Reylé, C. and Ribeiro, R.A. and Riva, A. and Rixon, G. and Roelens, M. and Romero-Gómez, M. and Rowell, N. and Royer, F. and Ruiz-Dern, L. and Sadowski, G. and Sagristà Sellés, T. and Sahlmann, J. and Salgado, J. and Salguero, E. and Sarasso, M. and Savietto, H. and Schultheis, M. and Sciacca, E. and Segol, M. and Segovia, J.C. and Segransan, D. and Shih, I.-C. and Smareglia, R. and Smart, R.L. and Solano, E. and Solitro, F. and Sordo, R. and Soria Nieto, S. and Souchay, J. and Spagna, A. and Spoto, F. and Stampa, U. and Steele, I.A. and Steidelmüller, H. and Stephenson, C.A. and Stoev, H. and Suess, F.F. and Süveges, M. and Surdej, J. and Szegedi-Elek, E. and Tapiador, D. and Taris, F. and Tauran, G. and Taylor, M.B. and Teixeira, R. and Terrett, D. and Tingley, B. and Trager, S.C. and Turon, C. and Ulla, A. and Utrilla, E. and Valentini, G. and Van Elteren, A. and Van Hemelryck, E. and Van Leeuwen, M. and Varadi, M. and Vecchiato, A. and Veljanoski, J. and Via, T. and Vicente, D. and Vogt, S. and Voss, H. and Votruba, V. and Voutsinas, S. and Walmsley, G. and Weiler, M. and Weingrill, K. and Wevers, T. and Wyrzykowski, L. and Yoldas, A. and Zerjal, M. and Zucker, S. and Zurbach, C. and Zwitter, T. and Alecu, A. and Allen, M. and Allende Prieto, C. and Amorim, A. and Anglada-Escudé, G. and Arsenijevic, V. and Azaz, S. and Balm, P. and Beck, M. and Bernstein, H.-H. and Bigot, L. and Bijaoui, A. and Blasco, C. and Bonfigli, M. and Bono, G. and Boudreault, S. and Bressan, A. and Brown, S. and Brunet, P.-M. and Bunclark, P. and Buonanno, R. and Butkevich, A.G. and Carret, C. and Carrion, C. and Chemin, L. and Chéreau, F. and Corcione, L. and Darmigny, E. and De Boer, K.S. and De Teodoro, P. and De Zeeuw, P.T. and Delle Luche, C. and Domingues, C.D. and Dubath, P. and Fodor, F. and Frézouls, B. and Fries, A. and Fustes, D. and Fyfe, D. and Gallardo, E. and Gallegos, J. and Gardiol, D. and Gebran, M. and Gomboc, A. and Gómez, A. and Grux, E. and Gueguen, A. and Heyrovsky, A. and Hoar, J. and Iannicola, G. and Isasi Parache, Y. and Janotto, A.-M. and Joliet, E. and Jonckheere, A. and Keil, R. and Kim, D.-W. and Klagyivik, P. and Klar, J. and Knude, J. and Kochukhov, O. and Kolka, I. and Kos, J. and Kutka, A. and Lainey, V. and Lebouquin, D. and Liu, C. and Loreggia, D. and Makarov, V.V. and Marseille, M.G. and Martayan, C. and Martinez-Rubi, O. and Massart, B. and Meynadier, F. and Mignot, S. and Munari, U. and Nguyen, A.-T. and Nordlander, T. and O'Flaherty, K.S. and Ocvirk, P. and Olias Sanz, A. and Ortiz, P. and Osorio, J. and Oszkiewicz, D. and Ouzounis, A. and Park, P. and Pasquato, E. and Peltzer, C. and Peralta, J. and Péturaud, F. and Pieniluoma, T. and Pigozzi, E. and Poels, J. and Prat, G. and Prod'Homme, T. and Raison, F. and Rebordao, J.M. and Risquez, D. and Rocca-Volmerange, B. and Rosen, S. and Ruiz-Fuertes, M.I. and Russo, F. and Serraller Vizcaino, I. and Short, A. and Siebert, A. and Silva, H. and Sinachopoulos, D. and Slezak, E. and Soffel, M. and Sosnowska, D. and StraizYs, V. and Ter Linden, M. and Terrell, D. and Theil, S. and Tiede, C. and Troisi, L. and Tsalmantza, P. and Tur, D. and Vaccari, M. and Vachier, F. and Valles, P. and Van Hamme, W. and Veltz, L. and Virtanen, J. and Wallut, J.-M. and Wichmann, R. and Wilkinson, M.I. and Ziaeepour, H. and Zschocke, S.",
    journal = "Chinese Astronomy and Astrophysics",
    year = "2017",
    volume = "605",
    publisher = "EDP Sciences",
    issn = "0275-1062",
    doi = "10.1051/0004-6361/201629925",
    keywords = "Astrophysics;  Curve fitting;  Geometrical optics;  Iodine;  Linear transformations;  Luminance;  Mathematical transformations, Astrometry;  Methods:data analysis;  Parallaxes;  Stars: distances;  Stars: variables: Cepheids;  Stars: variables: RR Lyrae, Stars",
    abstract = "Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims. In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, which involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity (PL), period-Wesenheit (PW) relations for classical and Type II Cepheids and infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity (MV-[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS. Methods. Classical Cepheids were carefully selected in order to discard known or suspected binary systems. The final sample comprises 102 fundamental mode pulsators with periods ranging from 1.68 to 51.66 days (of which 33 with σΩ/Ω< 0.5). The Type II Cepheids include a total of 26 W Virginis and BL Herculis stars spanning the period range from 1.16 to 30.00 days (of which only 7 with σΩ/Ω< 0.5). The RR Lyrae stars include 200 sources with pulsation period ranging from 0.27 to 0.80 days (of which 112 with σΩ/Ω< 0.5). The new relations were computed using multi-band (V,I,J,Ks) photometry and spectroscopic metal abundances available in the literature, and by applying three alternative approaches: (i) linear least-squares fitting of the absolute magnitudes inferred from direct transformation of the TGAS parallaxes; (ii) adopting astrometry-based luminosities; and (iii) using a Bayesian fitting approach. The last two methods work in parallax space where parallaxes are used directly, thus maintaining symmetrical errors and allowing negative parallaxes to be used. The TGAS-based PL,PW,PLZ, and MV- [Fe/H] relations are discussed by comparing the distance to the Large Magellanic Cloud provided by different types of pulsating stars and alternative fitting methods. Results. Good agreement is found from direct comparison of the parallaxes of RR Lyrae stars for which both TGAS and HST measurements are available. Similarly, very good agreement is found between the TGAS values and the parallaxes inferred from the absolute magnitudes of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink method. TGAS values also compare favourably with the parallaxes inferred by theoretical model fitting of the multi-band light curves for two of the three classical Cepheids and one RR Lyrae star, which were analysed with this technique in our samples. The K-band PL relations show the significant improvement of the TGAS parallaxes for Cepheids and RR Lyrae stars with respect to the Hipparcos measurements. This is particularly true for the RR Lyrae stars for which improvement in quality and statistics is impressive. Conclusions. TGAS parallaxes bring a significant added value to the previous Hipparcos estimates. The relations presented in this paper represent the first Gaia-calibrated relations and form a work-in-progress milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia Data Release 2 (DR2) in 2018. © ESO, 2017."
}