Test of lepton universality with Λ b 0 → pK − ℓ + ℓ − decays
Creators: name: Aaij, R.
name: Abellán Beteta, C.
name: Ackernley, T.
name: Adeva, B.
name: Adinolfi, M.
name: Afsharnia, H.
name: Aidala, C. A.
name: Aiola, S.
name: Ajaltouni, Z.
name: Akar, S.
name: Albicocco, P.
name: Albrecht, J.
name: Alessio, F.
name: Alexander, M.
name: Alfonso Albero, A.
name: Alkhazov, G.
name: Alvarez Cartelle, P.
name: Alves, A. A.
name: Amato, S.
name: Amhis, Y.
name: An, L.
name: Anderlini, L.
name: Andreassi, G.
name: Andreotti, M.
name: Archilli, F.
name: Arnau Romeu, J.
name: Artamonov, A.
name: Artuso, M.
name: Arzymatov, K.
name: Aslanides, E.
name: Atzeni, M.
name: Audurier, B.
name: Bachmann, S.
name: Back, J. J.
name: Baker, S.
name: Balagura, V.
name: Baldini, W.
name: Baranov, A.
name: Barlow, R. J.
name: Barsuk, S.
name: Barter, W.
name: Bartolini, M.
name: Baryshnikov, F.
name: Bassi, G.
name: Batozskaya, V.
name: Batsukh, B.
name: Battig, A.
name: Bay, A.
name: Becker, M.
name: Bedeschi, F.
name: Bediaga, I.
name: Beiter, A.
name: Bel, L. J.
name: Belavin, V.
name: Belin, S.
name: Beliy, N.
name: Bellee, V.
name: Belous, K.
name: Belyaev, I.
name: Bencivenni, G.
name: Ben-Haim, E.
name: Benson, S.
name: Beranek, S.
name: Berezhnoy, A.
name: Bernet, R.
name: Berninghoff, D.
name: Bernstein, H. C.
name: Bertella, C.
name: Bertholet, E.
name: Bertolin, A.
name: Betancourt, C.
name: Betti, F.
name: Bettler, M. O.
name: Bezshyiko, Ia.
name: Bhasin, S.
name: Bhom, J.
name: Bieker, M. S.
name: Bifani, S.
name: Billoir, P.
name: Bizzeti, A.
name: Bjørn, M.
name: Blago, M. P.
name: Blake, T.
name: Blanc, F.
name: Blusk, S.
name: Bobulska, D.
name: Bocci, V.
name: Boente Garcia, O.
name: Boettcher, T.
name: Boldyrev, A.
name: Bondar, A.
name: Bondar, N.
name: Borghi, S.
name: Borisyak, M.
name: Borsato, M.
name: Borsuk, J. T.
name: Bowcock, T. J. V.
name: Bozzi, C.
name: Bradley, M. J.
name: Braun, S.
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name: Brodski, M.
name: Brodzicka, J.
name: Brossa Gonzalo, A.
name: Brundu, D.
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name: Büchler-Germann, A.
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name: Bursche, A.
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name: Byczynski, W.
name: Cadeddu, S.
name: Cai, H.
name: Calabrese, R.
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name: Calvi, M.
name: Calvo Gomez, M.
name: Camargo Magalhaes, P.
name: Camboni, A.
name: Campana, P.
name: Campora Perez, D. H.
name: Capriotti, L.
name: Carbone, A.
name: Carboni, G.
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Publisher: name: Apollo - University of Cambridge Repository
Year: 2020
Subjects: Regular Article - Experimental Physics
B physics
Branching fraction
Flavour Changing Neutral Currents
Hadron- Hadron scattering (experiments)
Rare decay

description: Abstract: The ratio of branching fractions of the decays Λb0 → pK−e+e− and Λb0 → pK−μ+μ−, RpK−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 &lt; q2&lt; 6.0 GeV2/c4 and the pK− mass range m(pK−) &lt; 2600 MeV/c2, the ratio of branching fractions is measured to be RpK−1=1.17−0.16+0.18±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 Λb0 → pK−e+e−.