Directional Track Selection Technique in CR39 SSNTD for lowyield reaction experiments

¹ ENEA, Fusion and Technologies for Nuclear Safety Department, C. R. Frascati, Via E. Fermi 45, 00044 Frascati ( Roma), Italy
² Centre d’Etudes Lasers Intenses et Applications (CELIA), Université de Bordeaux, CNRS, CEA, 351 cours de la liberation 33405 Talence, France
³ Cyclotron Institute, Texas AM University (TAMU), 120 Spence St, College Station, TX 77840, United States
⁴ Physics Department of the University and INFN, Largo B. Pontecorvo 3, 57127, Pisa, Italy
⁵ Institute of Plasma Physics and Laser Microfusion (IPPLM), Hery Street 23, 01-497 Warsaw, Poland, Poland

^* Corresponding author: riccardo.deangelis@enea.it

Published online: 9 January 2018

Abstract

There is a great interest in the study of p-¹¹B aneutronic nuclear fusion reactions, both for energy production and for determination of fusion cross-sections at low energies. In this context we performed experiments at CELIA in which energetic protons, accelerated by the laser ECLIPSE, were directed toward a solid Boron target. Because of the small cross-sections at these energies the number of expected reactions is low. CR39 Solid-State Nuclear Track Detectors (SSNTD) were used to detect the alpha particles produced. Because of the low expected yield, it is difficult to discriminate the tracks due to true fusion products from those due to natural background in the CR39. To this purpose we developed a methodology of particle recognition according to their direction with respect to the detector normal, able to determine the position of their source. We applied this to the specific experiment geometry, so to select from all the tracks those due to particles coming from the region of interaction between accelerated protons and solid boron target. This technique can be of great help on the analysis of SSNTD in experiments with low yield reactions, but can be also generally applied to any experiment where particles reach the track detector with known directions, and for example to improve the detection limit of particle spectrometers using CR39.