Inclusive J production in Z0 decays is observed via the leptonic decay mode J --> l+ l- (l = e,mu). We measure the branching ratio Br(Z0 --> J + X) = (4.1 +/- 0.7 (stat.) +/- 0.3 (sys.)) x 10(-3). We have calculated the fraction of the J mesons from b-hadron decay and find a branching ratio of Br(b --> J + X) = (1.3 +/- 0.2 (stat.) +/- 0.2 (sys.)) x 10(-2). We determine the average fractional energy of bottom hadrons [x(E)] = 0.70 +/- 0.03 (stat. ) +0.02/-0.01 (sys. ) using the momentum spectrum of the J mesons. From a study of the angle between the J and the most energetic jet, we set an upper limit on the branching ratio Br(Z0 --> qqg*BAR;g* --> J + X) < 7.0 x 10(-4) at 90% confidence level.
Inclusive J-production In Z(0) Decays
SANTOCCHIA, Attilio;FIANDRINI, Emanuele;PAULUZZI, Michele
1992
Abstract
Inclusive J production in Z0 decays is observed via the leptonic decay mode J --> l+ l- (l = e,mu). We measure the branching ratio Br(Z0 --> J + X) = (4.1 +/- 0.7 (stat.) +/- 0.3 (sys.)) x 10(-3). We have calculated the fraction of the J mesons from b-hadron decay and find a branching ratio of Br(b --> J + X) = (1.3 +/- 0.2 (stat.) +/- 0.2 (sys.)) x 10(-2). We determine the average fractional energy of bottom hadrons [x(E)] = 0.70 +/- 0.03 (stat. ) +0.02/-0.01 (sys. ) using the momentum spectrum of the J mesons. From a study of the angle between the J and the most energetic jet, we set an upper limit on the branching ratio Br(Z0 --> qqg*BAR;g* --> J + X) < 7.0 x 10(-4) at 90% confidence level.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.