Isospin-dependence of the charge-changing cross-section shaped by the charged-particle evaporation process

Abstract

We present the charge-changing cross sections (CCCS) of ${}^{11-15}$C, ${}^{13-17}$N, and ${}^{15,17-18}$O at around 300 MeV/nucleon on a carbon target, which extends to $p$-shell isotopes with $N<Z$ for the first time. The Glauber model, which considers only the proton distribution of projectile nuclei, underestimates the cross sections by more than 10\%. We show that this discrepancy can be resolved by considering the contribution from the charged-particle evaporation process (CPEP) following projectile neutron removal. Using nucleon densities from the deformed relativistic Hartree-Bogoliubov theory in continuum, we investigate the isospin-dependent CPEP contribution to the CCCS for a wide range of neutron-to-proton separation energy asymmetry. Our calculations, which include the CPEP contribution, agree well with existing systematic data and reveal an ``evaporation peak" at the isospin symmetric region where the neutron-to-proton separation energy is close to zero. These results suggest that analysis beyond the Glauber model is crucial for accurately determining nuclear charge radii from CCCSs.

5 figures

References in corpus (7)

• Proton distribution radii of ${}^{12-19}$C illuminate features of neutron halos
• Peeling off neutron skins from neutron-rich nuclei: Constraints on the symmetry energy from neutron-removal cross sections
• Neutron skin and signature of the $N$ = 14 shell gap found from measured proton radii of ${}^{17-22}$N
• Proton distribution radii of ${}^{16-24}$O: signatures of new shell closures and neutron skin
• Charge-changing-cross-section measurements of ${}^{12-16}$C at around $45A$ MeV and development of a Glauber model for incident energies $10A-2100A$ MeV
• Charge-changing cross sections for ${}^{42\text{–}51}$Ca and effect of charged-particle evaporation induced by neutron removal reaction
• Improvement of charge resolution for radioactive heavy ions at relativistic energies using a hybrid detector system

Cited by in corpus (8)

• A new approach for deducing rms proton radii from charge-changing reactions of neutron-rich nuclei and the reaction-target dependence
• New quantification of symmetry energy from neutron skin thicknesses of ${}^{48}$Ca and ${}^{208}$Pb
• Single-proton removal reaction in the IQMD+GEMINI model benchmarked by elemental fragmentation cross sections of ${}^{29-33}\mathrm{Si}$ on carbon at $\sim$230~MeV/nucleon
• Triaxial relativistic Hartree-Bogoliubov theory in continuum for exotic nuclei
• Full realization of the RIBLL2 separator at the HIRFL-CSR facility
• Correlation between the charge radii difference in mirror partner nuclei and the symmetry energy slope
• Theoretical investigation of charge-changing cross section and interaction cross section for Be, B, C, N, O, and F isotopes on ${}^{12}$C at 200-1050 MeV/nucleon
• Role of nuclear and electromagnetic fragmentation in the charge-changing reactions of 18O on carbon and lead targets at around 370 MeV/nucleon