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               <dc:title>Search for a muonic dark force at BaBar</dc:title>
               <dc:creator>Graugés Pous, Eugeni</dc:creator>
               <dc:creator>BABAR Collaboration</dc:creator>
               <dc:subject>Partícules (Matèria)</dc:subject>
               <dc:subject>Matèria fosca (Astronomia)</dc:subject>
               <dc:subject>Particles</dc:subject>
               <dc:subject>Dark matter (Astronomy)</dc:subject>
               <dc:description>Many models of physics beyond the standard model predict the existence of new Abelian forces with new gauge bosons mediating interactions between "dark sectors" and the standard model. We report a search for a dark boson Z ′ coupling only to the second and third generations of leptons in the reaction e + e − → μ + μ − Z ′ , Z ′ → μ + μ − using 514     fb − 1 of data collected by the BABAR experiment. No significant signal is observed for Z ′ masses in the range 0.212-10 GeV. Limits on the coupling parameter g ′ as low as 7 × 10 − 4 are derived, leading to improvements in the bounds compared to those previously derived from neutrino experiments.</dc:description>
               <dc:date>2018-01-30T12:14:28Z</dc:date>
               <dc:date>2018-01-30T12:14:28Z</dc:date>
               <dc:date>2016-07-19</dc:date>
               <dc:date>2018-01-30T12:14:28Z</dc:date>
               <dc:type>info:eu-repo/semantics/article</dc:type>
               <dc:type>info:eu-repo/semantics/publishedVersion</dc:type>
               <dc:relation>Reproducció del document publicat a: https://doi.org/10.1103/PhysRevD.94.011102</dc:relation>
               <dc:relation>Physical Review D, 2016, vol. 94, num. 1, p. 11102-1-11102-7</dc:relation>
               <dc:relation>https://doi.org/10.1103/PhysRevD.94.011102</dc:relation>
               <dc:rights>(c) American Physical Society, 2016</dc:rights>
               <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
               <dc:publisher>American Physical Society</dc:publisher>
               <dc:source>Articles publicats en revistes (Física Quàntica i Astrofísica)</dc:source>
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