  In case of the discovery of supersymmetry at the LHC, the goal will be to
identify the underlying theory, its fundamental parameters, and the masses of
SUSY particles. We followed here the approach to reconstruct the decay chains
in SUSY events under the assumption of common intermediate masses. These masses
cannot be extracted from each event because of the unmeasured LSP momenta in
case of R-parity conservation. But an ensemble of events can be
over-constrained, if the decay chains are long enough, such that enough mass
constraints are available. Here, we present a new method combining a) a SUSY
mass scan, b) a kinematic fitting based on a genetic algorithm for decay chain
reconstruction, and c) the usage of angular decay information to suppress the
background from other SUSY processes. Taking into account the full
combinatorial background and experimental resolutions in the most difficult
case of the fully hadronic decay mode, we demonstrate, within one SUSY
scenario, that this method can be used to derive a probability map of the SUSY
parameter space.
