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arXiv · 1902.02092

Measurement of the ratio of branching fractions of the decays $\Lambda^0_b\!\to\psi(2S) \Lambda$ and $\Lambda^0_b\!\to J/\psi \Lambda$

LHCb Collaboration·R. Aaij·B. Adeva·M. Adinolfi·Z. Ajaltouni·S. Akar·J. Albrecht·F. Alessio·M. Alexander·A. Alfonso Albero·S. Ali·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·S. Amerio·Y. Amhis·L. An·L. Anderlini·G. Andreassi·M. Andreotti·J. E. Andrews·R. B. Appleby·F. Archilli·J. Arnau Romeu·A. Artamonov·M. Artuso·E. Aslanides·M. Atzeni·G. Auriemma·M. Baalouch·I. Babuschkin·S. Bachmann·J. J. Back·A. Badalov·C. Baesso·S. Baker·V. Balagura·W. Baldini·A. Baranov·R. J. Barlow·C. Barschel·S. Barsuk·W. Barter·F. Baryshnikov·V. Batozskaya·V. Battista·A. Bay·L. Beaucourt·J. Beddow·F. Bedeschi·I. Bediaga·A. Beiter·L. J. Bel·N. Beliy·V. Bellee·N. Belloli·K. Belous·I. Belyaev·G. Bencivenni·E. Ben-Haim·S. Benson·S. Beranek·A. Berezhnoy·R. Bernet·D. Berninghoff·E. Bertholet·A. Bertolin·C. Betancourt·F. Betti·M. O. Bettler·Ia. Bezshyiko·S. Bifani·P. Billoir·A. Birnkraut·A. Bizzeti·M. Bjørn·T. Blake·F. Blanc·S. Blusk·V. Bocci·T. Boettcher·A. Bondar·N. Bondar·I. Bordyuzhin·S. Borghi·M. Borisyak·M. Borsato·F. Bossu·M. Boubdir·T. J. V. Bowcock·E. Bowen·C. Bozzi·S. Braun·J. Brodzicka·D. Brundu·E. Buchanan·C. Burr·A. Bursche·J. Buytaert
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Abstract

Using $pp$ collisions corresponding to 3$\,\text{fb}^{-1}$ integrated luminosity, recorded by the LHCb experiment at centre-of-mass energies of 7 and 8$\,\text{TeV}$, the ratio of branching fractions \begin{align*} \mathcal{B}(\Lambda^0_b\!\to\psi(2S) \Lambda )/\mathcal{B}(\Lambda^0_b\!\to J/\psi \Lambda)= 0.513 \pm 0.023\, (\text{stat}) \pm 0.016 \, (\text{syst}) \pm 0.011\, (\mathcal{B}) \end{align*} is determined. The first uncertainty is statistical, the second is systematic and the third is due to the external branching fractions used.

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LHCb Collaboration, R. Aaij, B. Adeva, M. Adinolfi, Z. Ajaltouni, S. Akar, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, S. Ali, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, S. Amerio, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, J. E. Andrews, R. B. Appleby, F. Archilli, J. Arnau Romeu, A. Artamonov, M. Artuso, E. Aslanides, M. Atzeni, G. Auriemma, M. Baalouch, I. Babuschkin, S. Bachmann, J. J. Back, A. Badalov, C. Baesso, S. Baker, V. Balagura, W. Baldini, A. Baranov, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, F. Baryshnikov, V. Batozskaya, V. Battista, A. Bay, L. Beaucourt, J. Beddow, F. Bedeschi, I. Bediaga, A. Beiter, L. J. Bel, N. Beliy, V. Bellee, N. Belloli, K. Belous, I. Belyaev, G. Bencivenni, E. Ben-Haim, S. Benson, S. Beranek, A. Berezhnoy, R. Bernet, D. Berninghoff, E. Bertholet, A. Bertolin, C. Betancourt, F. Betti, M. O. Bettler, Ia. Bezshyiko, S. Bifani, P. Billoir, A. Birnkraut, A. Bizzeti, M. Bjørn, T. Blake, F. Blanc, S. Blusk, V. Bocci, T. Boettcher, A. Bondar, N. Bondar, I. Bordyuzhin, S. Borghi, M. Borisyak, M. Borsato, F. Bossu, M. Boubdir, T. J. V. Bowcock, E. Bowen, C. Bozzi, S. Braun, J. Brodzicka, D. Brundu, E. Buchanan, C. Burr, A. Bursche, J. Buytaert. 2019-02-06. Measurement of the ratio of branching fractions of the decays $\Lambda^0_b\!\to\psi(2S) \Lambda$ and $\Lambda^0_b\!\to J/\psi \Lambda$. https://doi.org/10.1007/jhep03(2019)126

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