000003740 001__ 3740
000003740 005__ 20190114164815.0
000003740 0247_ $$2DOI$$a10.1051/0004-6361/201832865
000003740 037__ $$aSCART-2019-0024
000003740 100__ $$aGaia Collaboration
000003740 245__ $$aGaia Data Release 2. Mapping the Milky Way disc kinematics
000003740 260__ $$c2018
000003740 520__ $$aContext. 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 (σϖ/ϖ ≤ 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. 
000003740 594__ $$aNO
000003740 6531_ $$aGalaxy: kinematics and dynamics
000003740 6531_ $$aGalaxy: disk
000003740 6531_ $$asolar neighborhood
000003740 700__ $$aKatz, D.
000003740 700__ $$aAntoja, T.
000003740 700__ $$aRomero-Gómez, M.
000003740 700__ $$aDrimmel, R.
000003740 700__ $$aReylé, C.
000003740 700__ $$aSeabroke, G. M.
000003740 700__ $$aSoubiran, C.
000003740 700__ $$aBabusiaux, C.
000003740 700__ $$aDi Matteo, P.
000003740 700__ $$aFigueras, F.
000003740 700__ $$aPoggio, E.
000003740 700__ $$aRobin, A. C.
000003740 700__ $$aEvans, D. W.
000003740 700__ $$aBrown, A. G. A.
000003740 700__ $$aVallenari, A.
000003740 700__ $$aPrusti, T.
000003740 700__ $$ade Bruijne, J. H. J.
000003740 700__ $$aBailer-Jones, C. A. L.
000003740 700__ $$aBiermann, M.
000003740 700__ $$aEyer, L.
000003740 700__ $$aJansen, F.
000003740 700__ $$aJordi, C.
000003740 700__ $$aKlioner, S. A.
000003740 700__ $$aLammers, U.
000003740 700__ $$aLindegren, L.
000003740 700__ $$aLuri, X.
000003740 700__ $$aMignard, F.
000003740 700__ $$aPanem, C.
000003740 700__ $$aPourbaix, D.
000003740 700__ $$aRandich, S.
000003740 700__ $$aSartoretti, P.
000003740 700__ $$aSiddiqui, H. I.
000003740 700__ $$avan Leeuwen, F.
000003740 700__ $$aWalton, N. A.
000003740 700__ $$aArenou, F.
000003740 700__ $$aBastian, U.
000003740 700__ $$aCropper, M.
000003740 700__ $$aLattanzi, M. G.
000003740 700__ $$aBakker, J.
000003740 700__ $$aCacciari, C.
000003740 700__ $$aCasta n, J.
000003740 700__ $$aChaoul, L.
000003740 700__ $$aCheek, N.
000003740 700__ $$aDe Angeli, F.
000003740 700__ $$aFabricius, C.
000003740 700__ $$aGuerra, R.
000003740 700__ $$aHoll, B.
000003740 700__ $$aMasana, E.
000003740 700__ $$aMessineo, R.
000003740 700__ $$aMowlavi, N.
000003740 700__ $$aNienartowicz, K.
000003740 700__ $$aPanuzzo, P.
000003740 700__ $$aPortell, J.
000003740 700__ $$aRiello, M.
000003740 700__ $$aTanga, P.
000003740 700__ $$aThévenin, F.
000003740 700__ $$aGracia-Abril, G.
000003740 700__ $$aComoretto, G.
000003740 700__ $$aGarcia-Reinaldos, M.
000003740 700__ $$aTeyssier, D.
000003740 700__ $$aAltmann, M.
000003740 700__ $$aAndrae, R.
000003740 700__ $$aAudard, M.
000003740 700__ $$aBellas-Velidis, I.
000003740 700__ $$aBenson, K.
000003740 700__ $$aBerthier, J.
000003740 700__ $$aBlomme, R.
000003740 700__ $$aBurgess, P.
000003740 700__ $$aBusso, G.
000003740 700__ $$aCarry, B.
000003740 700__ $$aCellino, A.
000003740 700__ $$aClementini, G.
000003740 700__ $$aClotet, M.
000003740 700__ $$aCreevey, O.
000003740 700__ $$aDavidson, M.
000003740 700__ $$aDe Ridder, J.
000003740 700__ $$aDelchambre, L.
000003740 700__ $$aDell'Oro, A.
000003740 700__ $$aDucourant, C.
000003740 700__ $$aFernández-Hernández, J.
000003740 700__ $$aFouesneau, M.
000003740 700__ $$aFrémat, Y.
000003740 700__ $$aGalluccio, L.
000003740 700__ $$aGarcía-Torres, M.
000003740 700__ $$aGonzález-Núñez, J.
000003740 700__ $$aGonzález-Vidal, J. J.
000003740 700__ $$aGosset, E.
000003740 700__ $$aGuy, L. P.
000003740 700__ $$aHalbwachs, J.-L.
000003740 700__ $$aHambly, N. C.
000003740 700__ $$aHarrison, D. L.
000003740 700__ $$aHernández, J.
000003740 700__ $$aHestroffer, D.
000003740 700__ $$aHodgkin, S. T.
000003740 700__ $$aHutton, A.
000003740 700__ $$aJasniewicz, G.
000003740 700__ $$aJean-Antoine-Piccolo, A.
000003740 700__ $$aJordan, S.
000003740 700__ $$aKorn, A. J.
000003740 700__ $$aKrone-Martins, A.
000003740 700__ $$aLanzafame, A. C.
000003740 700__ $$aLebzelter, T.
000003740 700__ $$aLöffler, W.
000003740 700__ $$aManteiga, M.
000003740 700__ $$aMarrese, P. M.
000003740 700__ $$aMartín-Fleitas, J. M.
000003740 700__ $$aMoitinho, A.
000003740 700__ $$aMora, A.
000003740 700__ $$aMuinonen, K.
000003740 700__ $$aOsinde, J.
000003740 700__ $$aPancino, E.
000003740 700__ $$aPauwels, T.
000003740 700__ $$aPetit, J.-M.
000003740 700__ $$aRecio-Blanco, A.
000003740 700__ $$aRichards, P. J.
000003740 700__ $$aRimoldini, L.
000003740 700__ $$aSarro, L. M.
000003740 700__ $$aSiopis, C.
000003740 700__ $$aSmith, M.
000003740 700__ $$aSozzetti, A.
000003740 700__ $$aSüveges, M.
000003740 700__ $$aTorra, J.
000003740 700__ $$avan Reeven, W.
000003740 700__ $$aAbbas, U.
000003740 700__ $$aAbreu Aramburu, A.
000003740 700__ $$aAccart, S.
000003740 700__ $$aAerts, C.
000003740 700__ $$aAltavilla, G.
000003740 700__ $$aÁlvarez, M. A.
000003740 700__ $$aAlvarez, R.
000003740 700__ $$aAlves, J.
000003740 700__ $$aAnderson, R. I.
000003740 700__ $$aAndrei, A. H.
000003740 700__ $$aAnglada Varela, E.
000003740 700__ $$aAntiche, E.
000003740 700__ $$aArcay, B.
000003740 700__ $$aAstraatmadja, T. L.
000003740 700__ $$aBach, N.
000003740 700__ $$aBaker, S. G.
000003740 700__ $$aBalaguer-Núñez, L.
000003740 700__ $$aBalm, P.
000003740 700__ $$aBarache, C.
000003740 700__ $$aBarata, C.
000003740 700__ $$aBarbato, D.
000003740 700__ $$aBarblan, F.
000003740 700__ $$aBarklem, P. S.
000003740 700__ $$aBarrado, D.
000003740 700__ $$aBarros, M.
000003740 700__ $$aBarstow, M. A.
000003740 700__ $$aBartholomé Muñoz, L.
000003740 700__ $$aBassilana, J.-L.
000003740 700__ $$aBecciani, U.
000003740 700__ $$aBellazzini, M.
000003740 700__ $$aBerihuete, A.
000003740 700__ $$aBertone, S.
000003740 700__ $$aBianchi, L.
000003740 700__ $$aBienaymé, O.
000003740 700__ $$aBlanco-Cuaresma, S.
000003740 700__ $$aBoch, T.
000003740 700__ $$aBoeche, C.
000003740 700__ $$aBombrun, A.
000003740 700__ $$aBorrachero, R.
000003740 700__ $$aBossini, D.
000003740 700__ $$aBouquillon, S.
000003740 700__ $$aBourda, G.
000003740 700__ $$aBragaglia, A.
000003740 700__ $$aBramante, L.
000003740 700__ $$aBreddels, M. A.
000003740 700__ $$aBressan, A.
000003740 700__ $$aBrouillet, N.
000003740 700__ $$aBrüsemeister, T.
000003740 700__ $$aBrugaletta, E.
000003740 700__ $$aBucciarelli, B.
000003740 700__ $$aBurlacu, A.
000003740 700__ $$aBusonero, D.
000003740 700__ $$aButkevich, A. G.
000003740 700__ $$aBuzzi, R.
000003740 700__ $$aCaffau, E.
000003740 700__ $$aCancelliere, R.
000003740 700__ $$aCannizzaro, G.
000003740 700__ $$aCantat-Gaudin, T.
000003740 700__ $$aCarballo, R.
000003740 700__ $$aCarlucci, T.
000003740 700__ $$aCarrasco, J. M.
000003740 700__ $$aCasamiquela, L.
000003740 700__ $$aCastellani, M.
000003740 700__ $$aCastro-Ginard, A.
000003740 700__ $$aCharlot, P.
000003740 700__ $$aChemin, L.
000003740 700__ $$aChiavassa, A.
000003740 700__ $$aCocozza, G.
000003740 700__ $$aCostigan, G.
000003740 700__ $$aCowell, S.
000003740 700__ $$aCrifo, F.
000003740 700__ $$aCrosta, M.
000003740 700__ $$aCrowley, C.
000003740 700__ $$aCuypers, J.
000003740 700__ $$aDafonte, C.
000003740 700__ $$aDamerdji, Y.
000003740 700__ $$aDapergolas, A.
000003740 700__ $$aDavid, P.
000003740 700__ $$aDavid, M.
000003740 700__ $$ade Laverny, P.
000003740 700__ $$aDe Luise, F.
000003740 700__ $$aDe March, R.
000003740 700__ $$ade Souza, R.
000003740 700__ $$ade Torres, A.
000003740 700__ $$aDebosscher, J.
000003740 700__ $$adel Pozo, E.
000003740 700__ $$aDelbo, M.
000003740 700__ $$aDelgado, A.
000003740 700__ $$aDelgado, H. E.
000003740 700__ $$aDiakite, S.
000003740 700__ $$aDiener, C.
000003740 700__ $$aDistefano, E.
000003740 700__ $$aDolding, C.
000003740 700__ $$aDrazinos, P.
000003740 700__ $$aDurán, J.
000003740 700__ $$aEdvardsson, B.
000003740 700__ $$aEnke, H.
000003740 700__ $$aEriksson, K.
000003740 700__ $$aEsquej, P.
000003740 700__ $$aEynard Bontemps, G.
000003740 700__ $$aFabre, C.
000003740 700__ $$aFabrizio, M.
000003740 700__ $$aFaigler, S.
000003740 700__ $$aFalc a, A. J.
000003740 700__ $$aFarràs Casas, M.
000003740 700__ $$aFederici, L.
000003740 700__ $$aFedorets, G.
000003740 700__ $$aFernique, P.
000003740 700__ $$aFilippi, F.
000003740 700__ $$aFindeisen, K.
000003740 700__ $$aFonti, A.
000003740 700__ $$aFraile, E.
000003740 700__ $$aFraser, M.
000003740 700__ $$aFrézouls, B.
000003740 700__ $$aGai, M.
000003740 700__ $$aGalleti, S.
000003740 700__ $$aGarabato, D.
000003740 700__ $$aGarcía-Sedano, F.
000003740 700__ $$aGarofalo, A.
000003740 700__ $$aGarralda, N.
000003740 700__ $$aGavel, A.
000003740 700__ $$aGavras, P.
000003740 700__ $$aGerssen, J.
000003740 700__ $$aGeyer, R.
000003740 700__ $$aGiacobbe, P.
000003740 700__ $$aGilmore, G.
000003740 700__ $$aGirona, S.
000003740 700__ $$aGiuffrida, G.
000003740 700__ $$aGlass, F.
000003740 700__ $$aGomes, M.
000003740 700__ $$aGranvik, M.
000003740 700__ $$aGueguen, A.
000003740 700__ $$aGuerrier, A.
000003740 700__ $$aGuiraud, J.
000003740 700__ $$aGutié, R.
000003740 700__ $$aHaigron, R.
000003740 700__ $$aHatzidimitriou, D.
000003740 700__ $$aHauser, M.
000003740 700__ $$aHaywood, M.
000003740 700__ $$aHeiter, U.
000003740 700__ $$aHelmi, A.
000003740 700__ $$aHeu, J.
000003740 700__ $$aHilger, T.
000003740 700__ $$aHobbs, D.
000003740 700__ $$aHofmann, W.
000003740 700__ $$aHolland, G.
000003740 700__ $$aHuckle, H. E.
000003740 700__ $$aHypki, A.
000003740 700__ $$aIcardi, V.
000003740 700__ $$aJanßen, K.
000003740 700__ $$aJevardat de Fombelle, G.
000003740 700__ $$aJonker, P. G.
000003740 700__ $$aJuhász, Á. L.
000003740 700__ $$aJulbe, F.
000003740 700__ $$aKarampelas, A.
000003740 700__ $$aKewley, A.
000003740 700__ $$aKlar, J.
000003740 700__ $$aKochoska, A.
000003740 700__ $$aKohley, R.
000003740 700__ $$aKolenberg, K.
000003740 700__ $$aKontizas, M.
000003740 700__ $$aKontizas, E.
000003740 700__ $$aKoposov, S. E.
000003740 700__ $$aKordopatis, G.
000003740 700__ $$aKostrzewa-Rutkowska, Z.
000003740 700__ $$aKoubsky, P.
000003740 700__ $$aLambert, S.
000003740 700__ $$aLanza, A. F.
000003740 700__ $$aLasne, Y.
000003740 700__ $$aLavigne, J.-B.
000003740 700__ $$aLe Fustec, Y.
000003740 700__ $$aLe Poncin-Lafitte, C.
000003740 700__ $$aLebreton, Y.
000003740 700__ $$aLeccia, S.
000003740 700__ $$aLeclerc, N.
000003740 700__ $$aLecoeur-Taibi, I.
000003740 700__ $$aLenhardt, H.
000003740 700__ $$aLeroux, F.
000003740 700__ $$aLiao, S.
000003740 700__ $$aLicata, E.
000003740 700__ $$aLindstrøm, H. E. P.
000003740 700__ $$aLister, T. A.
000003740 700__ $$aLivanou, E.
000003740 700__ $$aLobel, A.
000003740 700__ $$aLópez, M.
000003740 700__ $$aManagau, S.
000003740 700__ $$aMann, R. G.
000003740 700__ $$aMantelet, G.
000003740 700__ $$aMarchal, O.
000003740 700__ $$aMarchant, J. M.
000003740 700__ $$aMarconi, M.
000003740 700__ $$aMarinoni, S.
000003740 700__ $$aMarschalkó, G.
000003740 700__ $$aMarshall, D. J.
000003740 700__ $$aMartino, M.
000003740 700__ $$aMarton, G.
000003740 700__ $$aMary, N.
000003740 700__ $$aMassari, D.
000003740 700__ $$aMatijevič, G.
000003740 700__ $$aMazeh, T.
000003740 700__ $$aMcMillan, P. J.
000003740 700__ $$aMessina, S.
000003740 700__ $$aMichalik, D.
000003740 700__ $$aMillar, N. R.
000003740 700__ $$aMolina, D.
000003740 700__ $$aMolinaro, R.
000003740 700__ $$aMolnár, L.
000003740 700__ $$aMontegriffo, P.
000003740 700__ $$aMor, R.
000003740 700__ $$aMorbidelli, R.
000003740 700__ $$aMorel, T.
000003740 700__ $$aMorris, D.
000003740 700__ $$aMulone, A. F.
000003740 700__ $$aMuraveva, T.
000003740 700__ $$aMusella, I.
000003740 700__ $$aNelemans, G.
000003740 700__ $$aNicastro, L.
000003740 700__ $$aNoval, L.
000003740 700__ $$aO'Mullane, W.
000003740 700__ $$aOrdénovic, C.
000003740 700__ $$aOrdóñez-Blanco, D.
000003740 700__ $$aOsborne, P.
000003740 700__ $$aPagani, C.
000003740 700__ $$aPagano, I.
000003740 700__ $$aPailler, F.
000003740 700__ $$aPalacin, H.
000003740 700__ $$aPalaversa, L.
000003740 700__ $$aPanahi, A.
000003740 700__ $$aPawlak, M.
000003740 700__ $$aPiersimoni, A. M.
000003740 700__ $$aPineau, F.-X.
000003740 700__ $$aPlachy, E.
000003740 700__ $$aPlum, G.
000003740 700__ $$aPoujoulet, E.
000003740 700__ $$aPrša, A.
000003740 700__ $$aPulone, L.
000003740 700__ $$aRacero, E.
000003740 700__ $$aRagaini, S.
000003740 700__ $$aRambaux, N.
000003740 700__ $$aRamos-Lerate, M.
000003740 700__ $$aRegibo, S.
000003740 700__ $$aRiclet, F.
000003740 700__ $$aRipepi, V.
000003740 700__ $$aRiva, A.
000003740 700__ $$aRivard, A.
000003740 700__ $$aRixon, G.
000003740 700__ $$aRoegiers, T.
000003740 700__ $$aRoelens, M.
000003740 700__ $$aRowell, N.
000003740 700__ $$aRoyer, F.
000003740 700__ $$aRuiz-Dern, L.
000003740 700__ $$aSadowski, G.
000003740 700__ $$aSagristà Sellés, T.
000003740 700__ $$aSahlmann, J.
000003740 700__ $$aSalgado, J.
000003740 700__ $$aSalguero, E.
000003740 700__ $$aSanna, N.
000003740 700__ $$aSantana-Ros, T.
000003740 700__ $$aSarasso, M.
000003740 700__ $$aSavietto, H.
000003740 700__ $$aSchultheis, M.
000003740 700__ $$aSciacca, E.
000003740 700__ $$aSegol, M.
000003740 700__ $$aSegovia, J. C.
000003740 700__ $$aSégransan, D.
000003740 700__ $$aShih, I.-C.
000003740 700__ $$aSiltala, L.
000003740 700__ $$aSilva, A. F.
000003740 700__ $$aSmart, R. L.
000003740 700__ $$aSmith, K. W.
000003740 700__ $$aSolano, E.
000003740 700__ $$aSolitro, F.
000003740 700__ $$aSordo, R.
000003740 700__ $$aSoria Nieto, S.
000003740 700__ $$aSouchay, J.
000003740 700__ $$aSpagna, A.
000003740 700__ $$aSpoto, F.
000003740 700__ $$aStampa, U.
000003740 700__ $$aSteele, I. A.
000003740 700__ $$aSteidelmüller, H.
000003740 700__ $$aStephenson, C. A.
000003740 700__ $$aStoev, H.
000003740 700__ $$aSuess, F. F.
000003740 700__ $$aSurdej, J.
000003740 700__ $$aSzabados, L.
000003740 700__ $$aSzegedi-Elek, E.
000003740 700__ $$aTapiador, D.
000003740 700__ $$aTaris, F.
000003740 700__ $$aTauran, G.
000003740 700__ $$aTaylor, M. B.
000003740 700__ $$aTeixeira, R.
000003740 700__ $$aTerrett, D.
000003740 700__ $$aTeyssandier, P.
000003740 700__ $$aThuillot, W.
000003740 700__ $$aTitarenko, A.
000003740 700__ $$aTorra Clotet, F.
000003740 700__ $$aTuron, C.
000003740 700__ $$aUlla, A.
000003740 700__ $$aUtrilla, E.
000003740 700__ $$aUzzi, S.
000003740 700__ $$aVaillant, M.
000003740 700__ $$aValentini, G.
000003740 700__ $$aValette, V.
000003740 700__ $$avan Elteren, A.
000003740 700__ $$aVan Hemelryck, E.
000003740 700__ $$avan Leeuwen, M.
000003740 700__ $$aVaschetto, M.
000003740 700__ $$aVecchiato, A.
000003740 700__ $$aVeljanoski, J.
000003740 700__ $$aViala, Y.
000003740 700__ $$aVicente, D.
000003740 700__ $$aVogt, S.
000003740 700__ $$avon Essen, C.
000003740 700__ $$aVoss, H.
000003740 700__ $$aVotruba, V.
000003740 700__ $$aVoutsinas, S.
000003740 700__ $$aWalmsley, G.
000003740 700__ $$aWeiler, M.
000003740 700__ $$aWertz, O.
000003740 700__ $$aWevers, T.
000003740 700__ $$aWyrzykowski, Ł.
000003740 700__ $$aYoldas, A.
000003740 700__ $$aŽerjal, M.
000003740 700__ $$aZiaeepour, H.
000003740 700__ $$aZorec, J.
000003740 700__ $$aZschocke, S.
000003740 700__ $$aZucker, S.
000003740 700__ $$aZurbach, C.
000003740 700__ $$aZwitter, T.
000003740 773__ $$cA11, 40 pp$$pAstronomy & Astrophysics$$v616$$y2018
000003740 8560_ $$fronny.blomme@observatoire.be
000003740 85642 $$ahttp://adsabs.harvard.edu/abs/2018A%26A...616A..11G
000003740 905__ $$apublished in
000003740 980__ $$aREFERD