NONSTANDARD STRING-SUSY SCENARIO AND ITS PHENOMENOLOGICAL IMPLICATIONS

We investigate the phenomenology of an orbifold string model in which supersymmetry breaking is dominated by the overall ''size'' modulus fi eld and all matter fields are in the untwisted sector. The possibly cl ose degeneracy of the lightest neutralino and chargino and the possibl y small splitting between the gluino and chargino or LSP mass imply th at discovery of supersymmetry at future colliders could be more challe nging than anticipated. Specialized search strategies and particular d etector features could play an important role. For preferred model par ameter choices, the phenomenology of dark matter in the universe is si gnificantly modified.