DOI 10.1007/s100529800857
Measurement of the W-pair cross-section
and of the W mass
in e+e-
interactions at 172 GeV
DELPHI Collabration, P.Abreu21 et al.
21 LIP, IST, FCUL - Av. Elias Garcia, 14-1o, PT-1000 Lisboa Codex, Portugal
Received: 12 December 1997 / Published online: 10 March 1998
Abstract
From a data sample of integrated luminosity,
collected by DELPHI at a centre-of-mass energy of 172 GeV, 118 events
were selected as W-pair candidates. From these, the branching fraction
was measured to be
and the
cross-section for the doubly resonant process
to be
pb.
The mass of the W boson, obtained from direct reconstruction
of the invariant mass of the fermion pairs in the decays
and
, was determined to be
,where "int.'' denotes
the uncertainty from interconnection effects like colour reconnection and
Bose-Einstein interference. Combined with the W mass obtained from the
cross-sections measured by DELPHI at threshold, a value of
was found.
Copyright Springer-Verlag