DOI 10.1007/s100529901073
Search for lightest neutralino and stau pair production in light gravitino scenarios with stau NLSP
The DELPHI Collaboration
P. Abreu21 - et al.
21 LIP, IST, FCUL - Av. Elias Garcia, 14-1o, PT-1000 Lisboa Codex, Portugal
Received: 20 October 1998 / Published online: 19 February 1999
Abstract
Promptly decaying lightest neutralinos and long-lived staus
are searched for in the context of light gravitino scenarios.
It is assumed that the stau is the next to lightest supersymmetric
particle (NLSP) and that the lightest neutralino is the next to NLSP (NNLSP).
Data collected with the Delphi
detector at centre-of-mass energies from 161 to 183GeV are analysed.
No evidence of the production of these particles is found.
Hence, lower mass limits for both kinds of particles are set at 95%
C.L.. The mass of gaugino-like neutralinos is found to be greater than
71.5GeV/c2.
In the search for long-lived stau, masses
less than 70.0 to 77.5 are excluded
for gravitino masses from 10 to 150. Combining this search
with the searches for stable heavy leptons and minimal supersymmetric
standard model
staus a lower limit of 68.5 may be set for the stau mass
independent of the mass of the gravitino.
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