The dynamic mechanics in the multinucleon transfer reaction ${}^{136}\mathrm{Xe}+{}^{208}\mathrm{Pb}$ at an incident energy of $E_{\mathrm{c}.\mathrm{m}.}=450$ MeV is investigated by using the improved quantum molecular dynamics model (ImQMD). The lifetime of the neck directly influences the nucleon exchange and energy dissipation between the projectile and the target. The total-kinetic-energy–mass distributions and excitation energy division of primary binary fragments and the mass distributions of primary fragments at different impact parameters are calculated. The thermal equilibrium between two reaction partners has been observed at the lifetime of a neck larger than $480\mathrm{fm}/c$. By using the statistical decay code gemini to describe the de-excitation process of the primary fragments, the isotope production cross sections from Pt to At are compared with the prediction by the dinuclear system and GRAZING model. The calculations indicate that the GRAZING model is suitable for estimating the isotope production cross sections only for $\mathrm{\Delta }Z=-1$ to +2; the DNS + gemini calculations underestimate the cross sections in the neutron-rich and neutron-deficient regions; and the ImQMD + gemini calculations give reasonable predictions of the isotope production cross sections for $\mathrm{\Delta }Z=-3$ to 0.

The multinucleon transfer reactions in collisions of ${}^{136}\mathrm{Xe}+{}^{198}\mathrm{Pt}$ at incident energies $E_{\mathrm{lab}}=5.25$, 6.20, 7.98, 10.0, and 15.0 MeV/nucleon are investigated by using the improved quantum molecular dynamics model. It is found that 6.20 MeV/nucleon is the optimal incident energy for producing the neutron-rich heavy nuclei. About 80 unknown neutron-rich nuclei might be produced in this reaction with cross sections from ${10}^{-6}$ to ${10}^{-2}$ mb. The angular distributions of the neutron-rich isotopes are predicted.

The isospin equilibration process in multinucleon transfer reactions is investigated by using the improved quantum molecular dynamics model. The collisions of ${}^{124}\mathrm{Xe}+{}^{208}\mathrm{Pb}$ at near-barrier energy are studied with different symmetry energy coefficients. We find that the neutron transfer is enhanced at the early stages of the collisions under the strong symmetry potential. The neutron's transfer takes place at an earlier stage than the proton's. The trajectory of neutron flow is along the low-density path from the target to projectile. The average $N/Z$ values of the primary products in the ${}^{58}\mathrm{Ni}+{}^{208}\mathrm{Pb}$ reaction are also investigated and compared with available experimental data. It shows that the average $N/Z$ values of the projectile-like products increase rapidly with increasing mass transfer. In the quasielastic collisions, the isospin equilibration process is incomplete due to a short contact time between the reaction partners. The complete isospin equilibration events take place in symmetric quasifission reactions.

The neutron capture cross sections of copper play a crucial role in the s process of stellar nucleosynthesis, the production of the medical isotope ⁶⁴ Cu for PET imaging and radiotherapy, and Neutron Resonance Capture Analysis for determining the elemental and isotopic compositions of archaeological and cultural heritage materials. The Cu(n,γ) cross section was measured from 1 eV to 700 keV at the Back-n facility of the Chinese Spallation Neutron Source using the time-of-flight method. Prompt γ-rays were detected by four C ₆ D ₆ liquid scintillator detectors, and the data were analyzed using the pulse height weighting technique. The results are generally consistent with the evaluated data in the major library; however, some discrepancies were observed, offering valuable insights into the differences between five prominent evaluated data libraries. The R -matrix SAMMY code was used to extract the resonance parameters for ^63,65 Cu in the resolved resonance region. Maxwellian-averaged cross sections were calculated within the temperature range relevant to the s process nucleosynthesis model, spanning kT =5-100 keV, based on the averaged cross sections in the unresolved resonance region. At kT =30 keV, the MACSs values for ⁶³ Cu (88.1±8.8 mb) and ⁶⁵ Cu (42.1±4.2 mb) were higher than the corresponding recommendations in the Karlsruhe Astrophysical Database of Nucleosynthesis in Stars.

Herein, a study of the correlation between nuclear temperature and symmetry energy is presented for heavy ion collisions at intermediate energies via the isospin-dependent quantum molecular-dynamics model. It is found that different symmetry energy parameters change the density and kinetic energy distribution of the hot nuclei. More importantly, nuclear temperatures that are based on kinetic energy properties can be used to study symmetry energy information.