  We present ProbReach, a tool for verifying probabilistic reachability for
stochastic hybrid systems, i.e., computing the probability that the system
reaches an unsafe region of the state space. In particular, ProbReach will
compute an arbitrarily small interval which is guaranteed to contain the
required probability. Standard (non-probabilistic) reachability is undecidable
even for linear hybrid systems. In ProbReach we adopt the weaker notion of
delta-reachability, in which the unsafe region is overapproximated by a
user-defined parameter (delta). This choice leads to false alarms, but also
makes the reachability problem decidable for virtually any hybrid system. In
ProbReach we have implemented a probabilistic version of delta-reachability
that is suited for hybrid systems whose stochastic behaviour is given in terms
of random initial conditions. In this paper we introduce the capabilities of
ProbReach, give an overview of the parallel implementation, and present results
for several benchmarks involving highly non-linear hybrid systems.
