First observations of the decays Λ0b→Λ+cD−(s) are reported using data corresponding to an integrated luminosity of 3 fb−1 collected at 7 and 8 TeV center-of-mass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction ℬ(B0s→D+D−s) is made and a search is performed for the decays B0(s)→Λ+cΛ−c. The results obtained are ℬ(Λ0b→Λ+cD−)/ℬ(Λ0b→Λ+cD−s)=0.042±0.003(stat)±0.003(syst),⎡⎣⎢⎢ℬ(Λ0b→Λ+cD−s)ℬ(B¯0→D+D−s)⎤⎦⎥⎥/[ℬ(Λ0b→Λ+cπ−)ℬ(B¯0→D+π−)]=0.96±0.02(stat)±0.06(syst),ℬ(B0s→D+D−s)/ℬ(B¯0→D+D−s)=0.038±0.004(stat)±0.003(syst),ℬ(B¯0→Λ+cΛ−c)/ℬ(B¯0→D+D−s)<0.0022[95% C.L.],ℬ(B0s→Λ+cΛ−c)/ℬ(B0s→D+D−s)<0.30[95% C.L.]. Measurement of the mass of the Λ0b baryon relative to the B¯0 meson gives M(Λ0b)−M(B¯0)=339.72±0.24(stat)±0.18(syst) MeV/c2. This result provides the most precise measurement of the mass of the Λ0b baryon to date.
Study of Beauty Hadron Decays into Pairs of Charm Hadrons
ANDREOTTI, Mirco;BALDINI, Wander;BOZZI, Concezio;CALABRESE, Roberto;CORVO, Marco;FIORE, Marco;FIORINI, Massimiliano;LUPPI, Eleonora;MANZALI, Matteo;SAVRIE', Mauro;TELLARINI, Giulia;TOMASSETTI, Luca;
2014
Abstract
First observations of the decays Λ0b→Λ+cD−(s) are reported using data corresponding to an integrated luminosity of 3 fb−1 collected at 7 and 8 TeV center-of-mass energies in proton-proton collisions with the LHCb detector. In addition, the most precise measurement of the branching fraction ℬ(B0s→D+D−s) is made and a search is performed for the decays B0(s)→Λ+cΛ−c. The results obtained are ℬ(Λ0b→Λ+cD−)/ℬ(Λ0b→Λ+cD−s)=0.042±0.003(stat)±0.003(syst),⎡⎣⎢⎢ℬ(Λ0b→Λ+cD−s)ℬ(B¯0→D+D−s)⎤⎦⎥⎥/[ℬ(Λ0b→Λ+cπ−)ℬ(B¯0→D+π−)]=0.96±0.02(stat)±0.06(syst),ℬ(B0s→D+D−s)/ℬ(B¯0→D+D−s)=0.038±0.004(stat)±0.003(syst),ℬ(B¯0→Λ+cΛ−c)/ℬ(B¯0→D+D−s)<0.0022[95% C.L.],ℬ(B0s→Λ+cΛ−c)/ℬ(B0s→D+D−s)<0.30[95% C.L.]. Measurement of the mass of the Λ0b baryon relative to the B¯0 meson gives M(Λ0b)−M(B¯0)=339.72±0.24(stat)±0.18(syst) MeV/c2. This result provides the most precise measurement of the mass of the Λ0b baryon to date.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.