CALIBRATION AND APPLICATION OF NUCLEAR TRACK DETECTORS FOR HIGH-TEMPERATURE PLASMA DIAGNOSTICS

Abstract The paper reports on features of so-called solid-state nuclear track detectors (SSNTDs), their calibration measurements performed with known ion beams, and their different applications for detailed studies of charged particle emissions from various high-temperatures plasma facilities

Estimation of the Impurity Levels in Polyimide Foils and the Life-Time of the Foils Irradiated by Charged Projectiles

Entrance windows to gas detectors or gas target-cells must satisfy many requirements. They must have: adequate mechanical strength to withstand gas pressure over a reasonably large aperture; thermal, chemical and radiation resistance; thickness homogeneity; no significant level of contaminates, and low stopping power to minimize energy loss of the projectiles, etc. In addition, they should be pin-hole free. Development of the in-situ polymerisation method used to produce the polyimide foils allowed preparation of very thin (10 µg/cm2) foils that are widely applied as backings in target preparation. Applicability of the foils prepared by this method as entrance windows to gas detectors is investigated. In the present studies two critical parameters of thin polyimide foils prepared by in-situ polymerization have been quantified. Namely: a) the level of impurities and their composition; b) the ability of the foils to withstand various beam currents (life time of the foil).JRC.D.4-Isotope measurement

High-resolution study of the Sn-116(p,t) reaction and shell model structure of Sn-114

The Sn-116(p, t) Sn-114 reaction has been studied in a high-resolution experiment at an incident proton energy of 26 MeV. Angular distributions for 61 transitions to levels of Sn-114 up to an excitation energy of similar to4.1 MeV have been measured. A distorted-wave Born approximation analysis of experimental angular distributions using conventional Woods-Saxon potentials has been done, allowing,either the confirmation of previous spin and parity values or the assignment of new spin and parity to a large number of Sn-114 states. A shell-model study of Sn-114 has been performed using a realistic effective interaction derived from the CD-Bonn nucleon-nucleon potential. The model space has been truncated to states with seniority up to 4. Comparison between the, experimental and calculated energy spectra for both positive- and negative-parity states shows a quite satisfactory agreement

Sn-120 homologous levels via the Sb-123((p)over-right-arrow,alpha)Sn-120 reaction: Experimental evidence and microscopic calculations

The Sb-123(p(->), alpha)Sn-120 reaction has been studied in a high resolution measurement at incident energy of 24 MeV using a polarized proton source and a Q3D spectrometer. The differential cross sections and asymmetries for transitions to levels of Sn-120 homologous to the lowest energy states of In-119 have been measured and interpreted in terms of the experimental differential cross sections and asymmetries of the parent In-119 states, on the basis of the weak-coupling model. Several (17) states of the Sn-120 residual nucleus, not previously reported in the literature, have been detected and spins and parities have been proposed for seven of them, while parities have been proposed for five other previously known levels. In order to analyze the transitions populating the homologous levels, for both differential cross sections and asymmetries, microscopic DWBA calculations have been performed using spectroscopic amplitudes obtained from a shell-model study

Quality of Polyimide Foils for Nuclear Applications in Relation to a New Preparation Procedure

For more than 30 years thin polyimide foils are produced at IRMM by in-situ polymerisation. The procedure consists of three steps, all performed under ambient conditions: preparation of a polycondensate solution used for foil forming by spreading on a glass plate, removal of the solvent by thermal treatment for four hours at 100°C and final polymerisation at high temperature (350°C). Recently modifications of this procedure including preparation in an argon atmosphere and elimination of the time-consuming solvent removal were applied. The influence of those modifications on the quality of the foils was studied by testing the mechanical and thermal properties and the lifetime of the foil under a charged projectile beam. The influence of the modifications on the characteristics an don the level of impurities in the foils is presented as well. The comparative studies of parameters were performed for foils with an areal density between 20 µg·cm-2 and 80 µg·cm-2. This work showed that the foils prepared by the new fast preparation way in a dry atmosphere have the best properties for nuclear physics applications.JRC.D.2-Reference material