Search for the lepton-flavour violating decays B( s)0 → e±μ

• Published in: The journal of high energy physics Vol. 2018; no. 3; pp. 1 - 20
• Main Authors: Alfonso Albero, A., Alkhazov, G., Alves, A. A., Appleby, R. B., Aslanides, E., Babuschkin, I., Badalov, A., Baker, S., Barlow, R. J., Barter, W., Baryshnikov, F., Beaucourt, L., Bediaga, I., Beliy, N., Bencivenni, G., Bezshyiko, Ia, Birnkraut, A., Blanc, F., Brundu, D., Calvi, M., Capriotti, L., Casse, G., Cassina, L., Cenci, R., Clemencic, M., Cogan, J., Cogneras, E., Collins, P., Contu, A., Dettori, F., Dzyuba, A., Esen, S., Ferrari, F., Ferro-Luzzi, M., Fiorini, M., Forshaw, D. C., Frei, C., Gandini, P., Garrido, L., Ghez, Ph, Gligorov, V. V., Gomes, A., Gys, T., Henry, L., Jacobsson, R., Jans, E., Jones, C. R., Karodia, S., Keizer, F., Khurewathanakul, C., Kirn, T., Lai, A., Lemaitre, F., Likhomanenko, T., Loh, D., Lucchesi, D., Lupato, A., Mancinelli, G., Mauri, A., Mitzel, D. S., Mulder, M., Müller, V., O’Hanlon, D. P., Pellegrino, A., Pistone, A., Poluektov, A., Pomery, G. J., Rachwal, B., Redi, F., Robbe, P., Rollings, A., Sagidova, N., Sanchez Mayordomo, C., Sanmartin Sedes, B., Satriano, C., Saunders, D. M., Schune, M.-H., Schwemmer, R., Shcheglov, Y., Simi, G., Sirendi, M., Skwarnicki, T., Smith, J., Stefkova, S., Stenyakin, O., Stepanova, M., Straticiuc, M., T’Jampens, S., Tekampe, T., Teubert, F., Tolk, S., Vagner, A., Valat, S., van Veghel, M., Websdale, D., Weiden, A., Wislicki, W., Wraight, K., Zhang, L., Zheng, Y.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.03.2018; Springer Nature B.V; SpringerOpen
• Subjects: B physics; Branching fraction; Classical and Quantum Gravitation; Confidence intervals; Decay; Elementary Particles; Flavor physics; Hadron-Hadron scattering (experiments); High energy physics; Large Hadron Collider; Leptons; Luminosity; Particle collisions; Physics; Physics and Astronomy; Quantum Field Theories; Quantum Field Theory; Quantum Physics; Rare decay; Regular Article - Experimental Physics; Relativity Theory; String Theory; Flavor physics; B physics; Branching fraction; Hadron-Hadron scattering (experiments); Rare decay
• ISSN: 1029-8479
• DOI: 10.1007/JHEP03(2018)078

A bstract A search for the lepton-flavour violating decays B s 0  →  e ± μ ∓ and B 0  →  e ± μ ∓ is performed based on a sample of proton-proton collision data corresponding to an integrated luminosity of 3 fb −1 , collected with the LHCb experiment at centre-of-mass energies of 7 and 8 TeV. The observed yields are consistent with the background-only hypothesis. Upper limits on the branching fraction of the B s 0  →  e ± μ ∓ decays are evaluated both in the hypotheses of an amplitude completely dominated by the heavy eigenstate and by the light eigenstate. The results are @ @ ℬ B s 0 → e ± μ ∓ < 6.3 5.4 × 1 0 − 9 and @ @ ℬ B s 0 → e ± μ ∓ < 7.2 6.0 × 1 0 − 9 at 95% (90%) confidence level, respectively. The upper limit on the branching fraction of the B 0 → e ± μ ∓ decay is also evaluated, obtaining @ @ ℬ B 0 → e ± μ ∓ < 1.3 1.0 × 1 0 − 9 at 95% (90%) confidence level. These are the strongest limits on these decays to date.