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arXiv · 1308.4544

Observation of the decay Bc+ -> Bs0 pi+

Abstract

The result of a search for the decay Bc+ -> Bs0 pi+ is presented, using the Bs0 -> Ds- pi+ and Bs0 -> J/psi Phi channels. The analysis is based on a data sample of pp collisions collected with the LHCb detector, corresponding to an integrated luminosity of 1 fb-1 taken at a center-of-mass energy of 7 TeV, and 2 fb-1 taken at 8 TeV. The decay Bc+ -> Bs0 pi+ is observed with significance in excess of five standard deviations independently in both decay channels. The measured product of the ratio of cross-sections and branching fraction is sigma(Bc+)/sigma(Bs0) x BR(Bc+ -> Bs0 pi+) = (2.37 \pm 0.31 (stat) \pm 0.11 (syst)^{+0.17}_{-0.13} (tau_Bc)) x 10^-3 in the pseudorapidity range 2 < eta(B) < 5, where the first uncertainty is statistical, the second is systematic and the third is due to the uncertainty on the Bc lifetime. This is the first observation of a B meson decaying to another B meson via the weak interaction.

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LHCb collaboration, R. Aaij, B. Adeva, M. Adinolfi, C. Adrover, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, S. Amerio, Y. Amhis, L. Anderlini, J. Anderson, R. Andreassen, J. E. Andrews, R. B. Appleby, O. Aquines Gutierrez, F. Archilli, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, M. Baalouch, S. Bachmann, J. J. Back, C. Baesso, V. Balagura, W. Baldini, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, Th. Bauer, A. Bay, J. Beddow, F. Bedeschi, I. Bediaga, S. Belogurov, K. Belous, I. Belyaev, E. Ben-Haim, G. Bencivenni, S. Benson, J. Benton, A. Berezhnoy, R. Bernet, M. -O. Bettler, M. van Beuzekom, A. Bien, S. Bifani, T. Bird, A. Bizzeti, P. M. Bjørnstad, T. Blake, F. Blanc, J. Blouw, S. Blusk, V. Bocci, A. Bondar, N. Bondar, W. Bonivento, S. Borghi, A. Borgia, T. J. V. Bowcock, E. Bowen, C. Bozzi, T. Brambach, J. van den Brand, J. Bressieux, D. Brett, M. Britsch, T. Britton, N. H. Brook, H. Brown, A. Bursche, G. Busetto, J. Buytaert, S. Cadeddu, O. Callot, M. Calvi, M. Calvo Gomez, A. Camboni, P. Campana, D. Campora Perez, A. Carbone, G. Carboni, R. Cardinale, A. Cardini, H. Carranza-Mejia, L. Carson, K. Carvalho Akiba, G. Casse, L. Cassina, L. Castillo Garcia. 2013-11-08. Observation of the decay Bc+ -> Bs0 pi+. https://doi.org/10.1103/physrevlett.111.181801

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