[en] A high-performance thermonuclear plasma is a strong source of nuclear radiation, which includes neutron emission from the main fusion reactions and gamma-rays born from the interaction of supra-thermal ions and plasma impurities. Spectroscopic measurements of both types of radiation are an indirect probe of the distribution function of the fast ions leading to nuclear emission. In this paper we present a selection of recent results obtained with neutron and gamma-ray spectroscopy as a means to study the energy distribution of supra-thermal particles in high-performance thermonuclear plasmas. We focus in particular on the advancements made possible by the combination of dedicated instrumentation and detailed models based on the nuclear physics behind the emission. Future developments are finally addressed, especially regarding the availability of compact detectors with spectroscopy capabilities, which open up to a full tomographic reconstruction of the fast-ion velocity space.

[en] This paper describes the realization of a sampler for concentrating radionuclides from large volume of natural waters with the purpose to determine their concentration levels and their physico-chemical forms. Sample is pumped at a flow rate of about 0.5 m³/h through a set of sequential filters with different pore sizes to achieve separation of 'particulate' from 'dissolved' forms. Filtered samples is then passed through sequential beds of cation and anion exchange resins and activated alumina to obtain separation of dissolved forms on the basis of their charge. Ammonium Hexacianocobalt Ferrate (NCFC is used as a selective exchanger for Cesium isotopes. Filter and exchangers are measured by computerized gamma spectrometry. Detection limits are of a few tenths of Bq per cubic meter of sample. The main results obtained during radioecological surveys are also presented

[en] The paper presents a brief overview of energetic particle diagnostics in fusion plasmas. Differences between techniques used in nuclear and non-nuclear machines are in particular underlined and the challenges faced by fast ion diagnostics in a burning plasma are discussed.

[en] This paper describes the design criteria, which were used for the realization of an automatic system for the real time monitoring of the artificial radioactivity in the air. Special attention was paid to minimize particulate losses along device ducts. Particulate losses showed to be lower than 10%. The minimum detectable activities and the particulate-collection showed, in every respect, to be equivalent to the traditional system. (author)

[en] The measurement of the gamma emitter radionuclides is quicker if direct field gamma spectrometry is used. The operations of setting and determination of the parameters necessary for the calculation of the results are described below. Furthermore, the good agreement between the results obtained by the direct measurement and those obtained by the sampling and the subsequent measurement in the laboratory, is show. (author)

[en] We are going to show you how to proceed for a rapid measurement in the field of the radionuclides gamma activities in soil, with the right calibration factors. This methodology is useful for simple and quick gamma-analysis in environmental study or during nuclear emergency situation. Comparison from the 'in situ' and laboratory measures are reported to provide an accurate methodology valuation. (author)

[en] Design of automatic system for real time air monitoring of radioactive particulates are relate. Recommendations are made for design and operation of sampling conduits to minimize losses. By means of experimental equipment loss of particles in long sampling conduits, minimum detectable activity and efficiency of gamma radiation detectable are evaluated. (author)

[en] A system based on a LaBr₃(Ce) scintillator and digital data acquisition is discussed in view of γ-ray spectroscopy measurements on a fusion burning plasma. High energy resolution and high rate capability of the system are demonstrated in laboratory tests and in dedicated experiments at nuclear accelerators. Preliminary results on sensitivity of the detector to 14 MeV neutrons are presented.

[en] High resolution neutron emission spectroscopy (NES) and gamma-ray spectroscopy (GRS) measurements of fast ions in high power fusion plasmas are reviewed. NES is a well established diagnostics of the velocity distribution of fast fuel ions and was recently used to investigate the interaction of energetic ions with MHD instabilities. High energy resolution GRS on fusion plasmas is a more recent application and was shown to provide information on the distribution function of fast minority ions accelerated by ICRH, such as ⁴He and ³He. Starting from measurements on today's high power D plasmas, fast ion measurements with NES and GRS in a DT burning plasma of next step tokamaks, such as ITER, are discussed. The enhanced neutron and gamma-ray fluxes expected on ITER will allow for time-resolved measurements of the fast fuel and minority ion dynamics in the ms time scale. The intensity of the alpha knock-on component in the 14 MeV neutron spectrum and of the 4.44 and 3.21 MeV gamma-ray peaks from the ⁹Be(α,nγ)¹²C reaction is studied as a diagnostics for the α particle slowing down distribution in a DT plasma. The results show that the two techniques are sensitive to different regions of the α particle phase space and thus provide complementary information. (paper)

[en] After a description of the sampling and measurement methods, the values of vegetables concentration for gamma emitters measured in Crescentino and San Germano Vercellese from May 1 to September 24, 1986 are here reported. In some sample ⁸⁹Sr and ⁹⁰Sr were also measured