Measurement of the mass splittings between the bb̄χb,J(1P) states
Article
Edwards, KW, Bellerive, A, Janicek, R et al. (1999). Measurement of the mass splittings between the bb̄χb,J(1P) states
. PHYSICAL REVIEW D, 59(3), 1-5. 10.1103/PhysRevD.59.032003
Edwards, KW, Bellerive, A, Janicek, R et al. (1999). Measurement of the mass splittings between the bb̄χb,J(1P) states
. PHYSICAL REVIEW D, 59(3), 1-5. 10.1103/PhysRevD.59.032003
We present new measurements of photon energies and branching fractions for the radiative transitions Y(2S)→γχb(J=0,1,2)(1P). The masses of the χb states are determined from the measured radiative photon energies. The ratio of mass splittings between the χb substates, r≡(MJ=2-MJ=1)/(MJ=1-MJ=0), with M the χb mass, provides information on the nature of the bb̄ confining potential. We find r(1P)=0.542 ±0.022±0.024. This value is somewhat lower than the previous world average, but more consistent with the theoretical expectation that r(1P)