The light gluino scenario

We investigate in detail the consequences of the supersymmetry scenario with a light (proportional 5 GeV) gluino and heavy (proportional 100 GeV) squarks, including gluino distribution and fragmentation effects, proposed to explain large missing psub(T) events observed at the CERN panti p collider. The effective gluino distribution in the nucleon is evaluated using the Altarelli-Parisi equations. Ambiguities in evaluating squark production with the effective gluino distribution are discussed. A plausible gluino fragmentation function is deduced from heavy-quark fragmentation functions; scaling violations in the gluino fragmentation function are taken into account. Fragmentation effects drastically reduce the missing psub(T) in light gluino jets. The present collider data do not rule out a light gluino with mass in the range of 3-5 GeV even if the anti g lifetime, from decay into a photino and a quark pair, is short. (orig.)