Verification of Process Rewrite Systems in normal form

We consider the problem of model–checking for Process Rewrite Systems (PRS s)in normal form. In a PRS in normal form every rewrite rule either only deals withprocedure calls and procedure termination, possibly with value return, (this kind ofrules allows to capture Pushdown Processes), or only deals with dynamic activationof processes and synchronization (this kind of rules allows to capture Petri Nets). Themodel-checking problem for PRS s and action-based linear temporal logic (ALTL) isundecidable. However, decidability of model–checking for PRS s and some interestingfragment of ALTL remains an open question. In this paper we state decidability re-sults concerning generalized acceptance properties about infinite derivations (infiniteterm rewritings) in PRS s in normal form. As a consequence, we obtain decidabilityof the model-checking (restricted to infinite runs) for PRS s in normal form and ameaningful fragment of ALTL.