TY  - JOUR
AU  - LHCb Collaboration (Aaij, R. et al
AU  - Garcia Martin, L. M.
AU  - Henry, L.
AU  - Jashal, B. K.
AU  - Martinez-Vidal, F.
AU  - Oyanguren, A.
AU  - Remon Alepuz, C.
AU  - Ruiz Vidal, J.
AU  - Sanchez Mayordomo, C.
PY  - 2020
DA  - 2020//
TI  - Isospin Amplitudes in Lambda(0)(b) -> J/psi Lambda (Sigma(0)) and Xi(0)(b)-> J/psi Xi(0) (Lambda) Decays
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 111802
EP  - 11pp
VL  - 124
IS  - 11
PB  - Amer Physical Soc
AB  - Ratios of isospin amplitudes in hadron decays are a useful probe of the interplay between weak and strong interactions and allow searches for physics beyond the standard model. We present the first results on isospin amplitudes in b-baryon decays, using data corresponding to an integrated luminosity of 8.5 fb(-1), collected with the LHCb detector in pp collisions at center of mass energies of 7, 8, and 13 TeV. The isospin amplitude ratio vertical bar A(1) (Delta(0)(b) -> J/psi(Sigma(0)) /A(0) (Delta(0)(b) -> J/psi Lambda)vertical bar, where the subscript on A indicates the final-state isospin, is measured to be less than 1/21.8 at 95% confidence level. The Cabibbo suppressed Xi(0)(b) -> J/psi Lambda decay is observed for the first time, allowing for the measurement vertical bar A(0) (Xi(0)(b) -> J/psi Lambda) / A(1/2 )(Xi(0)(b) -> J/psi Xi(0))vertical bar = 0.37 +/- 0.06 +/- 0.02, where the uncertainties are statistical and systematic, respectively.
SN  - 0031-9007
UR  - https://arxiv.org/abs/1912.02110
UR  - https://doi.org/10.1103/PhysRevLett.124.111802
DO  - 10.1103/PhysRevLett.124.111802
LA  - English
N1  - WOS:000519994700005
ID  - LHCbCollaborationAaij_etal2020
ER  -