The ratio of branching fractions of the decays Λ0 → pK−e+e− and Λ0 → pK−μ+μ−, −1, is measured for the first time using proton-proton collision data corresponding to an integrated luminosity of 4.7 fb−1 recorded with the LHCb experiment at center-of-mass energies of 7, 8 and 13 TeV. In the dilepton mass-squared range 0.1 < q2 < 6.0 GeV2/c4 and the pK− mass range m(pK−) < 2600 MeV/c2, the ratio of branching fractions is measured to be −1=1.17+0.18−0.16±0.07, where the first uncertainty is statistical and the second systematic. This is the first test of lepton universality with b baryons and the first observation of the decay Λ0 → pK−e+e−.

Test of lepton universality with Λb0→pK−ℓ+ℓ− decays / Aaij, R., Abellán Beteta, C., Ackernley, T., Adeva, B., Adinolfi, M., Afsharnia, H., Aidala, C.A., Aiola, S., Ajaltouni, Z., Akar, S., Albicocco, P., Albrecht, J., Alessio, F., Alexander, M., Alfonso Albero, A., Alkhazov, G., Alvarez Cartelle, P., Alves, A.A., Amato, S., Amhis, Y., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2020:5(2020). [10.1007/JHEP05(2020)040]

Test of lepton universality with Λb0→pK−ℓ+ℓ− decays

Capriotti, L.;Casse, G.;Sarti, A.;Sciubba, A.;
2020

Abstract

The ratio of branching fractions of the decays Λ0 → pK−e+e− and Λ0 → pK−μ+μ−, −1, is measured for the first time using proton-proton collision data corresponding to an integrated luminosity of 4.7 fb−1 recorded with the LHCb experiment at center-of-mass energies of 7, 8 and 13 TeV. In the dilepton mass-squared range 0.1 < q2 < 6.0 GeV2/c4 and the pK− mass range m(pK−) < 2600 MeV/c2, the ratio of branching fractions is measured to be −1=1.17+0.18−0.16±0.07, where the first uncertainty is statistical and the second systematic. This is the first test of lepton universality with b baryons and the first observation of the decay Λ0 → pK−e+e−.
2020
B physics, Branching fraction, Flavour Changing Neutral Currents, Hadron- Hadron scattering (experiments), Rare decay
01 Pubblicazione su rivista::01a Articolo in rivista
Test of lepton universality with Λb0→pK−ℓ+ℓ− decays / Aaij, R., Abellán Beteta, C., Ackernley, T., Adeva, B., Adinolfi, M., Afsharnia, H., Aidala, C.A., Aiola, S., Ajaltouni, Z., Akar, S., Albicocco, P., Albrecht, J., Alessio, F., Alexander, M., Alfonso Albero, A., Alkhazov, G., Alvarez Cartelle, P., Alves, A.A., Amato, S., Amhis, Y., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2020:5(2020). [10.1007/JHEP05(2020)040]
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1466332
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