Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays B0 s→D+ s+Xμν̄ ; B0 s→D0K+Xμν̄ are detected. Two structures are observed in the D0K+ mass spectrum at masses consistent with the known Ds1(2536)+ ; Ds2*(2573)+ mesons. The measured branching fractions relative to the total B-s0 semileptonic rate are B(B0 s→Ds2*+Xμν̄)/B(B0 s→Xμν̄)=(3.3±1.0±0.4)%, ; B(B0 s→D+ s1Xμν̄)/B(B0 s→Xμν̄)=(5.4±1.2±0.5)%, where the first uncertainty is statistical ; the second is systematic. This is the first observation of the D*+ s2 state in B0 s decays; we also measure its mass ; width. © 2011 CERN.
First observation of B0 s→D*s2+Xμν̄- decays
PAPPAGALLO, MARCO IGNAZIO;
2011-01-01
Abstract
Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays B0 s→D+ s+Xμν̄ ; B0 s→D0K+Xμν̄ are detected. Two structures are observed in the D0K+ mass spectrum at masses consistent with the known Ds1(2536)+ ; Ds2*(2573)+ mesons. The measured branching fractions relative to the total B-s0 semileptonic rate are B(B0 s→Ds2*+Xμν̄)/B(B0 s→Xμν̄)=(3.3±1.0±0.4)%, ; B(B0 s→D+ s1Xμν̄)/B(B0 s→Xμν̄)=(5.4±1.2±0.5)%, where the first uncertainty is statistical ; the second is systematic. This is the first observation of the D*+ s2 state in B0 s decays; we also measure its mass ; width. © 2011 CERN.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.