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Random Forest identification of the thin disc, thick disc, and halo Gaia-DR2 white dwarf population Torres Gil, Santiago Cantero, C. Rebassa Mansergas, Alberto Skorobogatov, G. Jiménez Esteban, F. M. Solano Márquez, Enrique Universitat Politècnica de Catalunya. Departament de Física Universitat Politècnica de Catalunya. GAA - Grup d'Astronomia i Astrofísica Àrees temàtiques de la UPC::Física::Astronomia i astrofísica White dwarf stars Stars--Luminosity function Stars--Masses Stars: white dwarfs Galaxy: stellar content Stars: luminosity function mass function Estels nans Galàxies -- Formació Gaia-DR2 has provided an unprecedented number of white dwarf candidates of ourGalaxy. In particular, it is estimated thatGaia-DR2 has observed nearly 400 000 ofthese objects and close to 18 000 up to 100 pc from the Sun. This large quantity ofdata requires a thorough analysis in order to uncover their main Galactic popula-tion properties, in particular the thin and thick disk and halo components. Takingadvantage of recent developments in artificial intelligence techniques, we make useof a detailed Random Forest algorithm to analyse an 8-dimensional space (equato-rial coordinates, parallax, proper motion components and photometric magnitudes)of accurate data provided byGaia-DR2 within 100 pc from the Sun. With the aid ofa thorough and robust population synthesis code we simulated the different compo-nents of the Galactic white dwarf population to optimize the information extractedfrom the algorithm for disentangling the different population components. The algo-rithm is first tested in a known simulated sample achieving an accuracyof 85.3%. Ourmethodology is thoroughly compared to standard methods based on kinematic criteriademonstrating that our algorithm substantially improves previous approaches. Oncetrained, the algorithm is then applied to theGaia-DR2 100 pc white dwarf sample,identifying 12 227 thin disk, 1410 thick disk and 95 halo white dwarf candidates, whichrepresent a proportion of 74:25:1, respectively. Hence, the numerical spatial densitiesare (3.6±0.4)×10-3pc-3, (1.2±0.4)×10-3pc-3and (4.8±0.4)×10-5pc-3forthe thin disk, thick disk and halo components, respectively. The populations thus ob-tained represent the most complete and volume-limited samples to date of the differentcomponents of the Galactic white dwarf population. Peer Reviewed Preprint 2019-03-13 Article Torres, S. [et al.]. Random Forest identification of the thin disc, thick disc, and halo Gaia-DR2 white dwarf population. "Montly Notices of the Royal Astronomical Society", 13 Març 2019, vol. 485, núm. 4, p. 5573-5589. 1365-2966 https://arxiv.org/pdf/1903.07362.pdf https://hdl.handle.net/2117/174260 10.1093/mnras/stz814 eng This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society Published by Oxford University Press on behalf of the Royal Astronomical Society. https://academic.oup.com/mnras/article-abstract/485/4/5573/5398538 info:eu-repo/grantAgreement/AEI/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/AYA2017-86274-P/ES/DEL ENFRIAMIENTO A LAS EXPLOSIONES: LA FISICA DE LOS OBJETOS COMPACTOS/ info:eu-repo/grantAgreement/SPAIN/MINECO/RYC-2016-20254 info:eu-repo/grantAgreement/AGAUR/SGR-661/201 info:eu-repo/grantAgreement/EC/H2020/653477/EU/Astronomy ESFRI and Research Infrastructure Cluster/ASTERICS http://creativecommons.org/licenses/by-nc-nd/3.0/es/ Open Access Attribution-NonCommercial-NoDerivs 3.0 Spain 17 p. application/pdf Oxford University Press