We present measurements of branching fractions and CP-violating asymmetries for two-body neutral B̅ meson decays to charged pions and kaons based on a sample of about 88×106 ϒ(4S)→BB̅ decays. From a time-independent fit we measure the charge-averaged branching fractions B(B0→π+π-)=(4.7±0.6±0.2)×10-6, B(B0→K+π-)=(17.9±0.9±0.7)×10-6, and the direct CP-violating charge asymmetry AKπ=-0.102±0.050±0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90% confidence intervals. From a time-dependent fit we measure the B0→π+π- CP-violating parameters Sππ=0.02±0.34±0.05 [-0.54,+0.58] and Cππ=-0.30±0.25±0.04 [-0.72,+0.12].
Measurements of branching fractions and CP-violating asymmetries in B0 --> pi+ pi-, K+ pi-, K+ K- decays
CONTRI, ROBERTO;LO VETERE, MAURIZIO;MONGE, MARIA ROBERTA;PATRIGNANI, CLAUDIA;ROBUTTI, ENRICO;SANTRONI, ALBERTO;TOSI, SILVANO;
2002-01-01
Abstract
We present measurements of branching fractions and CP-violating asymmetries for two-body neutral B̅ meson decays to charged pions and kaons based on a sample of about 88×106 ϒ(4S)→BB̅ decays. From a time-independent fit we measure the charge-averaged branching fractions B(B0→π+π-)=(4.7±0.6±0.2)×10-6, B(B0→K+π-)=(17.9±0.9±0.7)×10-6, and the direct CP-violating charge asymmetry AKπ=-0.102±0.050±0.016 [-0.188,-0.016], where the ranges in square brackets indicate the 90% confidence intervals. From a time-dependent fit we measure the B0→π+π- CP-violating parameters Sππ=0.02±0.34±0.05 [-0.54,+0.58] and Cππ=-0.30±0.25±0.04 [-0.72,+0.12].I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.