Searching for Invisible and Almost Invisible Particles at e^+e^- Colliders

Department of Physics, University of Wisconsin–Madison, Madison, Wisconsin, United States
Physical Review Letters (Impact Factor: 7.51). 12/1995; 76(12). DOI: 10.1103/PhysRevLett.76.2002
Source: arXiv


We explore the techniques, cross sections and expected signal significance
for detecting invisible and almost invisible particles at LEP2 and the NLC by
means of a hard photon tag. Examples from supersymmetry include the lightest
chargino and second lightest neutralino when their masses are nearly the same
as that of the lightest neutralino (the LSP), and invisibly decaying
sneutrinos. The importance of particular features of the detectors is
discussed, instrumentation for vetoing a fast e^+ or e^- in the beam hole being
especially crucial.

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