ALEPH four-jet excess, Rb and R-parity violation

We point out that the exotic 4-jet events reported by ALEPH may constitute a signal for supersymmetry with some relatively light superpartners and with explicitly broken R-parity. A parton level simulation shows that production of a pair of light chargions with their subsequent baryon-number violating decays (either through a stop or through a neutralino) could possibly give rise to this excess. The decay χ1− → t1b → dsb leads to signatures close to the experimental observations. The additional contributions to Rb in such a scenario are also discussed.