We have detected, by using stimulated emission, an atomic parity violation (APV) in the form of a chiral optical gain of a cesium vapor on the 7S-6P(3/2) transition, consecutive to linearly polarized 6S-7S excitation. We demonstrate the validity of this detection method of APV, by presenting a 9% accurate measurement of expected sign and magnitude. We stress several advantages of this new approach which fully exploits the cylindrical symmetry of the setup. Future measurements at the percent level will provide an important cross-check of an existing more precise result obtained by a different method.

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Architecture description languages are used to describe both the hardware and software architecture of an application, at system-level. The basic software components are intended to be developed independently, and then deployed on the described architecture. This separate development of the architecture and of the software raises the problem of early validation of the integrated system.In this paper, we propose to solve this problem by translating the architecture into an executable model, which can be simulated and validated together with the software components. More specifically, we consider the case where the architecture is described in the AADL language, and the software components are developed in some synchronous language like Scade or Lustre. We show how the architecture can be automatically translated into a non-deterministic synchronous model, to which the actual software component can be integrated. The result is an executable integrated synchronous model, which can be validated with tools available for synchronous programs. The approach is illustrated on an industrial case study extracted from an actual spatial system.

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This paper presents the language Lutin and its operational semantics. This language specifically targets the domain of reactive systems, where an execution is a (virtually) infinite sequence of input/output reactions. More precisely, it is dedicated to the description and the execution of constrained random scenarios. Its first use is for test sequence specification and generation. It can also be useful for early simulation of huge systems, where Lutin programs can be used to describe and simulate modules that are not yet fully developed. Basic statements are input/output relations expressing constraints on a single reaction. Those constraints are then combined to describe non deterministic sequences of reactions. The language constructs are inspired by regular expressions and process algebra (sequence, choice, loop, concurrency). Moreover, the set of statements can be enriched with user-defined operators. A notion of stochastic directives is also provided in order to finely influence the selection of a particular class of scenarios.

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