The mass of the W boson is obtained from reconstructed invariant mass distributions in W-pair events. The sample of W pairs is selected from 57 pb(-1) collected with the ALEPH detector in 1997 at a centre-of-mass energy of 183 GeV. The invariant mass distributions of reweighted Monte Carlo events are fitted separately to the experimental distributions in the q (q) over bar q (q) over bar and all l nu q (q) over bar channels to give the following W masses: m(W)(hadronic) = 80.461 +/- 0.177 (stat.) +/- 0.045 (syst.) +/- 0.056 (theory) GeV/c(2) m(W)(semileptonic) = 80.326 +/- 0.184 (stat.) +/- 0.040 (syst.) GeV/c(2) where the theory error represents the possible effects of final state interactions. The combination of these two measurements, including the LEP energy calibration uncertainty, gives m(W) = 80.393 +/- 0.128 (stat.) +/- 0.041 (syst.) +/- 0.028 (theory) +/- 0.021 (LEP) GeV/c(2) (C) 1999 Published by Elsevier Science B.V. All rights reserved.
Measurement of the W mass in e(+)e(-) collisions at 183 GeV
DE PALMA, Mauro
1999-01-01
Abstract
The mass of the W boson is obtained from reconstructed invariant mass distributions in W-pair events. The sample of W pairs is selected from 57 pb(-1) collected with the ALEPH detector in 1997 at a centre-of-mass energy of 183 GeV. The invariant mass distributions of reweighted Monte Carlo events are fitted separately to the experimental distributions in the q (q) over bar q (q) over bar and all l nu q (q) over bar channels to give the following W masses: m(W)(hadronic) = 80.461 +/- 0.177 (stat.) +/- 0.045 (syst.) +/- 0.056 (theory) GeV/c(2) m(W)(semileptonic) = 80.326 +/- 0.184 (stat.) +/- 0.040 (syst.) GeV/c(2) where the theory error represents the possible effects of final state interactions. The combination of these two measurements, including the LEP energy calibration uncertainty, gives m(W) = 80.393 +/- 0.128 (stat.) +/- 0.041 (syst.) +/- 0.028 (theory) +/- 0.021 (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.
