<?xml version="1.0" encoding="UTF-8"?><?xml-stylesheet type="text/xsl" href="static/style.xsl"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-04-13T05:54:41Z</responseDate><request verb="GetRecord" identifier="oai:www.recercat.cat:2117/104210" metadataPrefix="didl">https://recercat.cat/oai/request</request><GetRecord><record><header><identifier>oai:recercat.cat:2117/104210</identifier><datestamp>2026-01-28T04:22:46Z</datestamp><setSpec>com_2072_1033</setSpec><setSpec>col_2072_452950</setSpec></header><metadata><d:DIDL xmlns:d="urn:mpeg:mpeg21:2002:02-DIDL-NS" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:doc="http://www.lyncode.com/xoai" xsi:schemaLocation="urn:mpeg:mpeg21:2002:02-DIDL-NS http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-21_schema_files/did/didl.xsd">
   <d:Item id="hdl_2117_104210">
      <d:Descriptor>
         <d:Statement mimeType="application/xml; charset=utf-8">
            <dii:Identifier xmlns:dii="urn:mpeg:mpeg21:2002:01-DII-NS" xsi:schemaLocation="urn:mpeg:mpeg21:2002:01-DII-NS http://standards.iso.org/ittf/PubliclyAvailableStandards/MPEG-21_schema_files/dii/dii.xsd">urn:hdl:2117/104210</dii:Identifier>
         </d:Statement>
      </d:Descriptor>
      <d:Descriptor>
         <d:Statement mimeType="application/xml; charset=utf-8">
            <oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
               <dc:title>An asteroseismic constraint on the mass of the axion from the period drift of the pulsating da white dwarf star L19-2</dc:title>
               <dc:creator>Córsico, Alejandro H.</dc:creator>
               <dc:creator>Romero, Alejandra Daniela</dc:creator>
               <dc:creator>Althaus, Leandro G.</dc:creator>
               <dc:creator>García-Berro Montilla, Enrique</dc:creator>
               <dc:creator>Isern Vilaboy, Jordi</dc:creator>
               <dc:creator>Kepler, S.O.</dc:creator>
               <dc:creator>Miller Bartolami, Marcelo M.</dc:creator>
               <dc:creator>Sullivan, Denis J.</dc:creator>
               <dc:subject>Àrees temàtiques de la UPC::Física::Astronomia i astrofísica</dc:subject>
               <dc:subject>White dwarfs</dc:subject>
               <dc:subject>Particles (Nuclear physics)</dc:subject>
               <dc:subject>Elementary particles - stars</dc:subject>
               <dc:subject>Oscillations - stars</dc:subject>
               <dc:subject>ZZ Ceti stars</dc:subject>
               <dc:subject>White dwarfs</dc:subject>
               <dc:subject>Estels nans</dc:subject>
               <dc:description>We employ an asteroseismic model of L19-2, a relatively massive (Msstarf ~ 0.75 M¿) and hot (Teff ~ 12 100 K) pulsating DA (H-rich atmosphere) white dwarf star (DAV or ZZ Ceti variable), and use the observed values of the temporal rates of period change of its dominant pulsation modes (¿ ~ 113 s and ¿ ~ 192 s), to derive a new constraint on the mass of the axion, the hypothetical non-barionic particle considered as a possible component of the dark matter of the Universe. If the asteroseismic model employed is an accurate representation of L19-2, then our results indicate hints of extra cooling in this star, compatible with emission of axions of mass ma cos2ß lesssim 25 meV or an axion-electron coupling constant of gae lesssim 7 × 10-13.</dc:description>
               <dc:description>Peer Reviewed</dc:description>
               <dc:description>Postprint (published version)</dc:description>
               <dc:date>2016-07-01</dc:date>
               <dc:type>Article</dc:type>
               <dc:relation>http://iopscience.iop.org/article/10.1088/1475-7516/2016/07/036/meta</dc:relation>
               <dc:relation>Argentina/AGENCIA/Programa de Modernizacin Tecnolgica/BID 1728/OC-AR</dc:relation>
               <dc:relation>PIP 112- 200801-00940 grant from CONICET</dc:relation>
               <dc:relation>info:eu-repo/grantAgreement/MINECO//AYA2014-59084-P/ES/SIMULACIONES MULTIDIMENSIONALES DE NOVAS Y SUPERNOVAS IA/</dc:relation>
               <dc:relation>Brasil/CNPq</dc:relation>
               <dc:relation>PRONEX-FAPERGS/CNPq</dc:relation>
               <dc:rights>http://creativecommons.org/licenses/by-nc-nd/3.0/es/</dc:rights>
               <dc:rights>Open Access</dc:rights>
               <dc:rights>Attribution-NonCommercial-NoDerivs 3.0 Spain</dc:rights>
            </oai_dc:dc>
         </d:Statement>
      </d:Descriptor>
   </d:Item>
</d:DIDL></metadata></record></GetRecord></OAI-PMH>