Alfonso Albero, AlejandroGarcia Moreno, PaulaGarrido Beltrán, LluísGironella Gironell, PereGomez Fernandez, SergioGraugés Pous, EugeniLobo Salvia, AniolLópez Huertas, AlbertMarin Benito, CarlaMauricio Ferre, JoanVazquez Gomez, RicardoLHCb Collaboration2025-06-062025-06-0620231126-6708https://hdl.handle.net/2445/221429 A first search for the lepton-flavour violating decays B0 → K∗0 τ ±µ ∓ is presented. The analysis is performed using a sample of proton-proton collision data, collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV between 2011 and 2018, corresponding to an integrated luminosity of 9 fb−1 . No significant signal is observed, and upper limits on the branching fractions are determined to be B(B0 → K∗0 τ +µ −) < 1.0 (1.2) × 10−5 and B(B0 → K∗0 τ −µ +) < 8.2 (9.8) × 10−6 at the 90% (95%) confidence level.25 p.application/pdfengcc-by (c) Alfonso Albero, A. et al., 2023http://creativecommons.org/licenses/by/4.0/Física de partículesHadronsModel estàndard (Física nuclear)Particle physicsHadronsStandard model (Nuclear physics)info:eu-repo/semantics/article7570882025-06-06info:eu-repo/semantics/openAccess