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S e a r c h e s |
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Heavy Decaying Charged Particles |
Motivated by the possibility that, in Gauge Mediated Supersymmetric models,
the LSP is the Gravitino and the s-Tau may be the NLSP, decaying to:
s-Tau --> Tau + Gravitino
In this scenario, the s-Tau decay length may be observable
through a detectable kink on its track or through a measurable impact parameter.
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| decay length
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Complementary analyses :
DELPHI pursued several complementary analyses to cover all possibilities
of s-Tau decays:
Results from analyses 0+1+2 : (preliminary)
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| 172 GeV
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Individual results from the search for heavy stable charged particles,
the decay vertices (kinks) and the large impact parameters.
The 95% and 90% exclusion limits on the mass of the sTau_R are displayed.
The figures illustrate the different ranges of sensitivity to
the Gravitino mass achieved by the analyses.
Small impact parameters (analysis 3) : (preliminary)
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| 172 GeV
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This analysis reaches a better sensitivity in the region of low Gravitino masses,
down to about 1 eV.
Combined with the above analyses, it allows to exclude at 95% C.L.
a mass of the s-Tau_R below 55 GeV for Gravitino masses greater than 2.5 eV.
Heavy Lepton Search, all analyses combined : (preliminary)
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| 172 GeV
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Combining all analyses, including the standard MSSM search,
a mass of the s-Tau_R below 55.5 GeV is excluded at 95% C.L.
independent of the Gravitino mass.
REFERENCES :
The latest results on this analysis are :
Preliminary search for long-lived s-Tau using the DELPHI detector
Paper submitted to the HEP'97 Conference, Jerusalem, August 19-26,
paper #350.
(PS)
Earlier results were presented by :
F.Richard,
DELPHI Results at 172 GeV,
Cern seminar, 25/02/97.