Sub-surface nuclear tests monitoring through the CTBT xenon network

We present the first evaluation of the atmospheric xenon network to be installed as part of the International Monitoring System (IMS) in the frame of the Comprehensive Test Ban Treaty (CTBT). We show that this network should, by itself, provide a significant contribution to the total efficiency of the IMS. For this evaluation, we introduce an inverse approach based upon the time symmetry of the atmospheric transport of trace species. This approach may find applications in a variety of environmental problems.