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               <dc:title>Measurement of the effective B0s→K+K− lifetime</dc:title>
               <dc:creator>Garrido Beltrán, Lluís</dc:creator>
               <dc:creator>Graciani Díaz, Ricardo</dc:creator>
               <dc:creator>Graugés Pous, Eugeni</dc:creator>
               <dc:creator>LHCb Collaboration</dc:creator>
               <dc:subject>Física de partícules</dc:subject>
               <dc:subject>Mesons (Física nuclear)</dc:subject>
               <dc:subject>Experiments</dc:subject>
               <dc:subject>Gran Col·lisionador d'Hadrons</dc:subject>
               <dc:subject>Particle physics</dc:subject>
               <dc:subject>Mesons (Nuclear physics)</dc:subject>
               <dc:subject>Experiments</dc:subject>
               <dc:subject>Large Hadron Collider (France and Switzerland)</dc:subject>
               <dc:description>A precise determination of the effective B0 s → K + K − lifetime can be used to constrain contributions from physics beyond the Standard Model in the B0 s meson system. Conventional approaches select B meson decay products that are significantly displaced from the B meson production vertex. As a consequence, B mesons with low decay times are suppressed, introducing a bias to the decay time spectrum which must be corrected. This analysis uses a technique that explicitly avoids a lifetime bias by using a neural network based trigger and event selection. Using 1.0 fb−1 of data recorded by the LHCb experiment, the effective B0 s → K + K − lifetime is measured as 1.455 ± 0.046 (stat.) ± 0.006 (syst.) ps. © 2012 CERN. Published by Elsevier B.V. All rights reserved.</dc:description>
               <dc:date>2023-03-21T12:00:11Z</dc:date>
               <dc:date>2023-03-21T12:00:11Z</dc:date>
               <dc:date>2012-07</dc:date>
               <dc:date>2023-03-21T12:00:11Z</dc:date>
               <dc:type>info:eu-repo/semantics/article</dc:type>
               <dc:type>info:eu-repo/semantics/acceptedVersion</dc:type>
               <dc:relation>Versió postprint del document publicat a: https://doi.org/10.1016/j.physletb.2012.08.033</dc:relation>
               <dc:relation>Physics Letters B, 2012, vol. 716, p. 393-400</dc:relation>
               <dc:relation>https://doi.org/10.1016/j.physletb.2012.08.033</dc:relation>
               <dc:rights>(c) Elsevier B.V., 2012</dc:rights>
               <dc:rights>info:eu-repo/semantics/openAccess</dc:rights>
               <dc:publisher>Elsevier B.V.</dc:publisher>
               <dc:source>Articles publicats en revistes (Física Quàntica i Astrofísica)</dc:source>
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