Study of Bs0 → J/ψπ+π-K+K- decays

Authors：Aaij, R.; Beteta, C. Abellan; Ackernley, T.; Adeva, B.; Adinolfi, M.; Afsharnia, H.; Aidala, C. A.; Aiola, S.; Ajaltouni, Z.; Akar, S.; Albrecht, J.; Alessio, F.; Alexander, M.; Alfonso Albero, A.; Aliouche, Z.; Alkhazov, G.; Cartelle, P. Alvarez; Amato, S.; Amhis, Y.; An, L.; Anderlini, L.; Andreianov, A.; Andreotti, M.; Archilli, F.; Artamonov, A.; Artuso, M.; Arzymatov, K.; Aslanides, E.; Atzeni, M.; Audurier, B.; Bachmann, S.; Bachmayer, M.; Back, J. J.; Baker, S.; Baladron Rodriguez, P.

Source：JOURNAL OF HIGH ENERGY PHYSICS, 2021, (2): 024.

DOI：10.1007/JHEP02(2021)024

• B physics
• Branching fraction
• Hadron-Hadron scattering (experiments)
• Quarkonium
• Spectroscopy

The decays B-s(0) -> J/psi pi(+)pi-K+K- are studied using a data set corresponding to an integrated luminosity of 9 fb(-1), collected with the LHCb detector in proton-proton collisions at centre-of-mass energies of 7, 8 and 13TeV. The decays B-s(0) -> J/psi K*(K) over bar *0 and B-s(0) -> chi(c1)(3872)K+K-, where the K+K- pair does not originate from a phi meson, are observed for the first time. Precise measurements of the ratios of branching fractions between intermediate chi(c1)(3872)phi, J/psi K*0 (K) over bar *0, psi(2S)phi and chi(c1)(3872)K+K- states are reported. A structure, denoted as X(4740), is observed in the J/psi phi mass spectrum and, assuming a Breit-Wigner parameterisation, its mass and width are determined to be @@@ m(X(4740)) = 4741 +/- 6 +/- 6 MeV/c(2), @@@ Gamma(X(4740)) = 53 +/- 15 +/- 11MeV, @@@ where the first uncertainty is statistical and the second is systematic. In addition, the most precise single measurement of the mass of the B-s(0) meson is performed and gives a value of @@@ m(Bs)(0) = 5366.98 +/- 0.07 +/- 0.13MeV/c(2).