Usage of a corrected Bethe–Bloch formula for charge identification of fast ions with Z⩾30 recorded in polycarbonate track detectors

Abstract

The Bethe–Bloch formula is commonly used to calculate energy losses and ranges of charged massive (m≫me) particles when they penetrate into a given absorber. In order to make the formula applicable to ions of any charge and energy travelling inside any given material, several corrections must be introduced. To identify the charge of unknown ions employing SSNTDs, a track formation model, based on the energy deposition of the incident particles in the absorber, is needed. The Restricted Energy Loss (REL) model assumes that only the energy deposition due to distant collisions of the incident ion with the absorber atoms contributes effectively to track formation. In this work, the effect on the charge identification process of considering the corrections to the Bethe–Bloch formula is studied, as well as the possible effect of considering a contribution of the close collisions to the REL model. The identification procedure is applied to the Ultra Heavy cosmic ray ions recorded in the Ultra Heavy Cosmic Ray Experiment.