Marín Benito, CarlaOlivart Pino, ErnestSalvador Carreté, Marc2025-09-192025-09-192025-06https://hdl.handle.net/2445/223297Treballs Finals de Grau de Física, Facultat de Física, Universitat de Barcelona, Curs: 2025, Tutors: Carla Marín Benito, Ernest Olivart PinoIn this work, a study of the B+ → π+μ+μ− decay is performed in the new data collected during Run 3 of the LHCb experiment. A Boosted Decision Tree (BDT) algorithm is used to select the events corresponding to this decay and mass fits are performed to extract its yield. The B+ → π+J/ψ(→ μ+μ−) decay is used as a control channel. Using the yield of the control channel, the expected signal yield is found to be 1.64±0.22. No signal events have been found by performing a fit directly, which is compatible with the expectations.8 p.application/pdfengcc-by-nc-nd (c) Salvador, 2025http://creativecommons.org/licenses/by-nc-nd/3.0/es/Física de partículesAprenentatge automàticTreballs de fi de grauParticle physicsMachine learningBachelor's thesesinfo:eu-repo/semantics/bachelorThesisinfo:eu-repo/semantics/openAccess