Eur. Phys. J. C 16, 253-267
DOI 10.1007/s100520000400
Search for resonances decaying to e+-jet
in e+p interactions at HERA
The ZEUS Collaboration
J. Breitweg - et al.
Received: 15 February 2000 / Published online: 18 May 2000 - © Springer-Verlag 2000
Abstract
The e+-jet invariant
mass spectrum produced in the reaction
has been
studied at a center-of-mass energy of 300 GeV.
The data were
collected using the ZEUS detector operating at the HERA collider, and
correspond to an integrated luminosity of 47.7 pb-1.
The observed mass spectrum is in good agreement with Standard Model
expectations up to an e+-jet mass of 210 GeV. Above this mass,
some excess is seen. The angular distribution of these events is
typical of high-Q2 neutral current events and does not give
convincing evidence for the presence of a narrow scalar or vector
state.
Limits are presented on the product of cross section and branching ratio
for such a state and are interpreted
as limits on leptoquark or R-parity-violating squark production.
Specific leptoquark types are ruled out at 95% confidence level
for coupling strength
for masses between 150 and 280 GeV.
Copyright Società Italiana di Fisica, Springer-Verlag 2000
