An Evaluation of Energy-loss Straggling Calculation of the LISE++ Code

Abstract

Energy loss straggling was found to be critical in evaluating the energy reaction using heavy-ion beams during the early stage of experiments at accelerator facilities. Despite a significant attempt in simulating this quantity using computer codes such as LISE++ and SRIM, there still exists a discrepancy between experimental data and computed results. In this study, we provide a greatly improved precision of estimations using the LISE++ code by evaluating the energy loss straggling of the alpha particles at 5.486 MeV in Tb, Ta, and Au materials. After comparing with the observables, it was found that the ratio of the energy loss straggling computed by the LISE++ code to that measured in experiments has a fairly large range of 1.5 - 3.0. For this reason, the so-called modified LISE++ calculation is constructed by adding the adjusting parameters into the original estimation to minimize the uncertainty of the straggling prediction. The modified calculation has shown dramatic improvements in computed energy loss straggling, which are almost similar to those obtained in the measurements, of 5.486-MeV alphas in the aforementioned materials with the atomic numbers in a range of Z = 65 – 79.