PT Journal
AU LHCb Collaboration (Aaij, Rea
   Henry, L
   Jashal, BK
   Martinez-Vidal, F
   Oyanguren, A
   Remon Alepuz, C
   Ruiz Vidal, J
TI Observation of New Resonances Decaying to J=Psi K plus and J=Psi phi
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2021
BP 082001
EP 11pp
VL 127
IS 8
DI 10.1103/PhysRevLett.127.082001
LA English
AB The first observation of exotic states with a new quark content ccus decaying to the J/Psi K+ final state is reported with high significance from an amplitude analysis of the B+-> J/ Psi phi K+ decay. The analysis is carried out using proton-proton collision data corresponding to a total integrated luminosity of 9 fb- 1 collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV. The most significant state, Z(cs)(4000)+, has a mass of 4003 +/- 6 (-14) (+4) MeV, a width of 131 +/- 15 +/- 26 MeV, and spin parity J(P) = 1(+), where the quoted uncertainties are statistical and systematic, respectively. A new 1(+) X(4685) state decaying to the J/Psi phi final state is also observed with high significance. In addition, the four previously reported J/Psi phi states are confirmed and two more exotic states, Z(cs) (4220) (+) and X(4630), are observed with significance exceeding 5 standard deviations.
ER