PT Journal
AU LHCb Collaboration (Aaij, Rea
   Jaimes Elles, SJ
   Jashal, BK
   Martinez-Vidal, F
   Oyanguren, A
   Rebollo De Miguel, M
   Remon Alepuz, C
   Ruiz Vidal, J
   Sanderswood, I
TI Evidence of a J / ψK0S Structure in B0 → J / ψφK0S Decays
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2023
BP 131901 - 11pp
VL 131
IS 13
DI 10.1103/PhysRevLett.131.131901
LA English
AB An amplitude analysis of B0 -> J=psi phi K0S decays is performed using proton-proton collision data, corresponding to an integrated luminosity of 9 fb-1, collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 TeV. Evidence with a significance of 4.0 standard deviations of a structure in the J=psi K0S system, named T theta psi s1o4000 thorn 0, is seen, with its mass and width measured to be 3991 thorn 12 thorn 9 -10 -17 MeV=c2 and 105 thorn 29 thorn 17 -25 -23 MeV, respectively, where the first uncertainty is statistical and the second systematic. The T theta psi s1 o4000 thorn 0 state is likely to be the isospin partner of the T theta psi s1 o4000 thorn thorn state, previously observed in the J=psi K thorn system of the B thorn -> J=psi phi K thorn decay. When isospin symmetry for the charged and neutral T theta psi s1 o4000 thorn states is assumed, the signal significance increases to 5.4 standard deviations.
ER