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The restoration of chiral symmetry and its subsequent breaking through a phase transition has been predicted to create regions of Disoriented Chiral Condensates (DCC). This phenomenon has been predicted to cause anomalous fluctuations in the relative production of charged and neutral pions in high-energy hadronic and nuclear collisions. The WA98 experiment has been used to measure charged and photon multiplicities in the central region of 158 AGeV Pb+Pb collisions at the CERN SPS. In a sample of 212646 events, no clear DCC signal can be distinguished. Using a simple DCC model, we have set a 90% C.L. upper limit on the maximum DCC production allowed by the data.

In case of a nuclear accident, decision makers rely on high resolution and accurate information about the spatial distribution of the radioactivity levels in the surroundings of the accident site. Static nuclear monitoring networks are therefore employed in many countries in Europe. However, these networks were designed to cover the whole country and are usually too course to reach a high density in the local environment around the accident site. Therefore a strategy is considered in which the measurement density is increased during emergencies by adding measurements from mobile measuring devices. This raises the question where the mobile devices should be placed. This paper proposes a geostatistical methodology to optimize the allocation of the mobile devices, such that the expected weighed sum of false negative and false positive areas, i.e., false classification into safe and unsafe zones is minimized. The radioactivity concentration was modelled as the sum of a deterministic trend and a zero-mean spatially correlated stochastic residual, whereby the deterministic trend was defined as the outcome of a spatially explicit physical atmospheric dispersion model (NPK-PUFF model). The NPK-PUFF model used meteorological data and the characteristics of the radioactive release as input. The residual was characterized by a semivariogram that was estimated from the differences between outputs from various NPK-PUFF runs with input settings reflecting the uncertainty in the NPK-PUFF inputs (e.g., wind speed, wind direction). Spatial simulated annealing was used to obtain the optimal monitoring design, whereby accessibility and openness of sampling sites was also included. The method was computationally demanding but results were promising and the computational speed may be considerably improved to compute the optimal monitoring network in nearly real-time.

-Recommendations and requirements for the management of foodstuffs including drinking water and feedstuffs (but not other commodities) contaminated after a nuclear accident or a radiological event have been developed by international bodies such as Codex Alimentarius Commission or European Union as well as by individual countries. However, the experience from severe nuclear accidents (Chernobyl, Fukushima) and less serious radiological events, shows that the implementation of such systems (based on criteria expressed in activity concentration) seems to be not fully suitable to prevent several difficulties such as, for instance, stigmatization and even rejection attitudes from consumers or retailers (anticipating the fears of consumers). To further investigate the possible strategies and stakeholder expectations to deal with this sensitive issue, a study has been launched within the European research project PREPARE-WP3. The overall objective of this work, coordinated is to contribute to the development of strategies, guidance and tools for the management of the contaminated products, taking into account the views of producers, processing and retail industries and consumers. For this purpose, 10 stakeholder panels from different European countries have been set up. In addition, feedback experience from the management of contaminated goods following the Fukushima accident has been provided by Japanese stakeholders. This paper highlights the key topics tackled by the different European stakeholders' panels.