The cross-section for the process e(+)e(-) --> W+W- has been measured with the data sample collected by DELPHI at an average centre-of-mass energy of 182.65 GeV and corresponding to an integrated luminosity of 53 pb(-1). Based on the 770 events selected as WW candidates, the cross-section for the: doubly resonant process sigma(e(+)e(-) --> W+W-) = 15.86 +/- 0.69(stat) +/- 0.26(syst) pb has been measured and found to be in good agreement with the Standard Model expectation. The branching fractions of the W decay were also measured. From these a value of the CKM mixing matrix element \V-cs\ = 0.985 +/- 0.073 (stat) +/- 0.025(syst) was derived. Our previously published WW cross-section measurements and the derived measurement of m(w) have been revised and updated with the present cross-section measurement to yield m(W) = 80.49 +/- 0.43(stat) +/- 0.09(syst) +/- 0.03(LEP) GeV/c(2). (C) 1999 Published by Elsevier Science B.V. All rights reserved.
W pair production cross-section and W branching fractions in e(+)e(-) interactions at 183 GeV
AMAPANE, Nicola Carlo;MIGLIORE, Ernesto;ROMERO, Alessandra;
1999-01-01
Abstract
The cross-section for the process e(+)e(-) --> W+W- has been measured with the data sample collected by DELPHI at an average centre-of-mass energy of 182.65 GeV and corresponding to an integrated luminosity of 53 pb(-1). Based on the 770 events selected as WW candidates, the cross-section for the: doubly resonant process sigma(e(+)e(-) --> W+W-) = 15.86 +/- 0.69(stat) +/- 0.26(syst) pb has been measured and found to be in good agreement with the Standard Model expectation. The branching fractions of the W decay were also measured. From these a value of the CKM mixing matrix element \V-cs\ = 0.985 +/- 0.073 (stat) +/- 0.025(syst) was derived. Our previously published WW cross-section measurements and the derived measurement of m(w) have been revised and updated with the present cross-section measurement to yield m(W) = 80.49 +/- 0.43(stat) +/- 0.09(syst) +/- 0.03(LEP) GeV/c(2). (C) 1999 Published by Elsevier Science B.V. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.