Abstract-The nuclear radiation energy deposition rate (unit usually employed: W.g -1 ) is a key parameter for the thermal design of experiments on materials and nuclear fuel carried out in experimental channels of irradiation reactors, such as the French reactor in Saclay called OSIRIS or the Polish reactor named MARIA. In particular the quantification of nuclear heating allows the prediction of heat and thermal conditions induced in irradiated devices and/or structural materials. Various sensors are used to quantify this parameter, in particular radiometric calorimeters, also known as in-pile calorimeters. Two main kinds of in-pile calorimeter exist possessing two geometries and two measurement principles: the single-cell calorimeter and the differential calorimeter. The present work focuses on specific examples of these calorimeter types, from the step of their out-of-pile calibration (transient and steady experiments respectively) to the comparison between numerical and experimental results obtained from two irradiation campaigns (French and Polish reactors). The main aim of this paper is to propose a steady numerical approach to estimate the single-cell calorimeter response under irradiation conditions.

The main objective of this project is to develop calculation scheme for the evaluation of gamma heating at any chosen location for both JHR (Jules-Horowitz Reactor) and MARIA reactor. JHR is the future material testing reactor under construction on the Cadarache CEA site (the reactor is going to operate after 2016) and MARIA is an existing Polish reactor having characteristics close to those of JHR.For that purpose both, simulations tools and experimental program, are being developed. Calculations will be carried out with both JHR model and MARIA layout. TRIPOLI4 and APOLLO2 codes will be used for calculations of the gamma heating in reactor cores. Representative calculation scheme for MARIA is needed in view to identify optimal locations for measurements according to JHR needs. The correctness of calculations will be qualified by a comparison with the experimental measurements performed in MARIA reactor. Instrumentation which will be used for these measurements have to be properly calibrated. The main aim of the present paper is to propose a calibration procedure for gamma heating measurements Index Terms-reactor gamma heating, Jules Horowitz Reactor -JHR, MARIA reactor.

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We present a trigger based on a pipelined artificial neural network implemented in a large FPGA which after learning can recognize different types of waveforms from the Pierre Auger surface detectors. The structure of an artificial neural network algorithm being developed on a MATLAB platform has been implemented into the fast logic of the largest Cyclone V E FPGA used for the prototype of the Front-End Board for the Auger-Beyond-2015. Several algorithms were tested, from which the Levenberg-Marquardt one (trainlm) seems to be the most efficient. The network was taught: a) to recognize "old" showers learning from real Auger very inclined showers (positive markers) and real standard showers especially triggered by Time over Threshold (negative marker), b) to recognize "young" showers from simulated "young" events (positive markers) and standard Auger events as a negative reference. A three-layer neural network being taught by real very inclined Auger showers shows a good efficiency in pattern recognition of 16-point traces with profiles characteristic for "old" showers. Nevertheless, preliminary simulations of showers with CORSIKA and the response of the water Cherenkov tanks with OffLine suggest that for neutrino showers starting a development deeply in the atmosphere and with relatively small initial energy eV, signal waveforms are not to long and a 16-point analysis should be sufficient for recognition of "young" showers. The neural network algorithm can significantly support detection at small energies, where a denser neutrino stream is expected. For higher energies traces are longer, however, the detector response is strong enough for the showers to be detected by standard amplitude-based triggers.