Charge-Changing Cross Sections of 736 A MeV ²⁸ Si on Carbon Targets

Abstract

The total and partial charge-changing cross sections of 28Si on carbon targets at 736 and 723 A MeV are studied by CR-39 plastic nuclear track detectors using the HSP-1000 microscope system and the PitFit track measurement software. The values of the total charge-changing cross section are and at 736 and 723 A MeV, respectively. The result is compared with the ones obtained by other experimental and theoretical results. The odd–even effect of the partial charge-changing cross section is observed.

New measurement of the elemental fragmentation cross sections of 218 MeV/nucleon 28 Si on a carbon target

“…The first and second parentheses in our present data are the statistical and systematic uncertainties, respectively. The experimental data can be classified into two groups by using either active detectors (like silicon or ionization chambers) [3,5,7] or CR-39 detectors [4,8,9]. Our present measurements for charge changes ∆Z = 1-6 at 218 MeV/nucleon are generally consistent with those at 266 and 268 MeV/nucleon within uncertainties.…”

“…We analyzed the dependence on the incident energy of fragment cross sections with ∆Z = 1-6. By excluding the CR-39 results [8,9], the existing data show in general a decreasing cross section for ∆Z = 3-6, but there is no decisive conclusion for ∆Z = 1 and 2.…”

“…We estimate hereafter the total uncertainty of cross section as the square root of the sum of statistical and systematic uncertainties. The data from CR-39 experiments [8,9] are not included here due to their relatively large uncertainties. In a global view, the data do not give a consistent energy dependence for ∆Z = 1 and 2.…”

“…Moreover, the elemental fragmentation cross sections (EFCSs) performed at similar incident energies for the same reaction system [3,5,7] present a large discrepancy by up to about 40%, albeit with similar heavy-ion detector systems. In addition, the cross sections at 700-800 MeV/nucleon [8,9], which were extracted by using CR-39 detectors, have relatively large uncertainties and are systematically larger than those measured by the active heavy-ion detectors. Such divergence in experimental data could be due to the systematic uncertainties in the relevant experiments.…”

“…Over the last two decades, experimental studies on the fragmentation of 28 Si have been performed at various energies by using different detection techniques in laboratories worldwide [3][4][5][6][7][8][9]. This isotope offers an ideal benchmark dataset to check the consistency of experiments, to evaluate the model reliability, and further to investigate the nuclear structure underneath the heavyion collisions.…”