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The correlation between neutron-to-proton yield ratio (R(np)) and neutron skin thickness (delta(np)) in neutron-rich projectile induced reactions is investigated within the framework of the Isospin-Dependent Quantum Molecular Dynamics (IQMD) model. The density distribution of the Droplet model is embedded in the initialization of the neutron and proton densities in the present IQMD model. By adjusting the diffuseness parameter of neutron density in the Droplet model for the projectile, the relationship between the neutron skin thickness and the corresponding R(np) is obtained. The results show strong linear correlation between R(np) and delta(np) for neutron-rich Ca and Ni isotopes. It is suggested that R(np) may be used as an experimental observable to extract delta(np) for neutron-rich nuclei, which is very interesting in the study of the nuclear structure of exotic nuclei, the equation of state (EOS) of asymmetric nuclear matter and neutron-rich matter in astrophysics, etc.

Assuming a core plus valence nucleon structure, one-nucleon removal reaction is investigated within the framework of few-body Glauber theory. Fermi-type distribution is used for the core density, while the wavefunction of the valence nucleon is calculated by solving the single particle eigenvalue problem of the Schrodinger equation with the Woods-Saxon potential. The parallel momentum distribution (P(parallel to)) of the fragments is calculated for isotopes with 3 < Z < 18. A remarkable scaling property is observed from the dependence of the dimensionless quantity R(v)(2)/R(c)(2) on the full width at half maximum of the parallel momentum distribution (FWHM(P parallel to)). R(v)(2)/R(c)(2) is a measure of the exotic extent of the nuclear halo. Based on the obtained scaling law, FWHM(P parallel to) can be used as an experimental observable to extract R(v)(2)/R(c)(2) and measure the exotic extent for the nuclear halo.

The isoscaling behavior in the reaction system (58,64)Ni + (9)Be has been studied by using the heavy-ion phase-space exploration(HIPSE) model. The extracted isoscaling parameters alpha and beta for both heavy and light fragments for HIPSE model calculations are in good agreement with recent experimental data. The investigation shows that the parameters in the HIPSe model have some effect on the isoscaling parameter. The isoscaling parameters for hot and cold fragments have been extracted.

The temperature dependent width of the fission fragment distributions was simulated in the Langevin equation by taking two-parameter exponential form of the fission fragment mass variance at scission point for each fission event. The result can reproduce experimental data well, and it permits to make reliable estimate for unmeasured product yields near symmetry fission.

The dependence between neutron skin thickness and neutron abrasion cross section (sigma(nabr)) for neutron-rich nuclei is investigated within the framework of the statistical abrasion ablation model. Assuming that the density distributions for proton and neutron are of Fermi-type, and adjusting the diffuseness parameter of neutron density distribution in the droplet model, we find out the good linear correlation between the neutron skin thickness and the abrasion cross section sigma(nabr) for neutron-rich nuclei. The uncertainty of neutron skin thickness determined from sigma(nabr) is very small. It is suggested that sigma(nabr) can be used as a new experimental observable to extract the neutron skin thickness for neutron-rich nucleus. The scaling behaviours between neutron skin thickness and sigma(nabr), separately, for isotopes of Na26-35, Ar44-56, Ca48-60, Ni67-78 are also investigated.

We investigate the applicability of the independent atom model JAM) to elastic electron scattering from complex polyatomic molecules, namely C4H10 and C6H6, in the energy range 100-1000eV. The cross sections of the elastic electron scattering are calculated by employing the JAM together with the relativistic partial waves. The incorporation of both the modified absorption potential and the extended structural factor in the JAM makes the elastic differential cross sections and momentum transfer cross sections have a good agreement with the available experimental data. The present simple model seems to be insensitive to the complexity of the target molecules so that the proposed procedure can be quite useful for calculation of electron scattering from bio-molecules.

We investigate the differential cross sections (DCS) of elastic electron scattering from CH4, CF4 and SF6 at six impact energies in a range of 100-700eV by employing the independent atom model (IAM) together with the relativistic partial waves. The atom is present in an optical potential which is complex, spherically symmetric, and energy dependent. The optical potential of the atom is the sum of the direct static, dynamic polarization, local exchange and modified absorption potentials. The results obtained by using a modified absorption potential show significant improvements on the unmodified absorption potential results. The present results are generally in good agreement with experimental data available. In addition, the present results indicate that the structure of molecule manifests the observable effects on electron-molecule scattering.

A sequential decay model is used to study isoscaling, i.e. the factorization of the isotope ratios from sources of different isospins and sizes over a broad range of excitation energies, into fugacity terms of proton and neutron number, R21(N,Z) = Y2(N,Z)/Y1(N,Z) = Ce(αN+βZ). It is found that the isoscaling parameters α and β have a strong dependence on the isospin difference of equilibrated source and excitation energy, no significant influence of the source size on α and β has been observed. It is found that α and β decrease with the excitation energy and are linear functions of 1/T and Δ(Z/A)2 or Δ(N/A)2 of the sources. Symmetry energy coefficient Csym is constrained from the relationship of α and source Δ(Z/A)2, β and source Δ(N/A)2.

Ne and Mg isotope chains are investigated based on constrained calculations in the framework of a deformed relativistic mean-field (RMF) model with the NL075 parameter set. The calculated quadrupole deformation and binding energy are compared with other theoretical results as well as the available experimental data. It shows that the calculated deformations of Ne and Mg with the NL075 are more accurate than those obtained with the NL-SH. It is predicted that 19,29,32Ne and 20,31Mg maybe have a triaxial deformation and 25−28Ne and 27−30Mg exhibit a shape coexistence probably. The closure effect of neutron number N=8 for 20Mg is predicted to be very weak.

Distribution of the parallel momentum of $^{28}$Si fragments from the breakup of 30.7 MeV/nucleon $^{29}$P has been measured on C targets. The distribution has the FWHM with the value of 110.5 $\pm$ 23.5 MeV/c which is consistent quantitatively with Galuber model calculation assuming by a valence proton in $^{29}$P. The density distribution is also predicted by Skyrme-Hartree-Fock calculation. Results show that there might exist the proton-skin structure in $^{29}$P., Comment: 4 pages, 4 figures

A candidate for proton halo nucleus 23Al is investigated based on the constrained calculations in the framework of the deformed relativistic mean field (RMF) model with the NL075 parameter set. It is shown by the constrained calculations that the ground state of 23Al has a large deformation that corresponds to the prolate shape. With that large deformation, the non-constrained RMF calculation predicts that there appears an inversion between the 2s1/2 [211] and 1d5/2 [202] shells. The valence proton of 23Al is weakly bound and occupies 2s1/2 [211] and 1d5/2 [202] with the weights of 56% and 29%, respectively. The calculated RMS radius for matter is in agreement with the experimental one. It is also predicted that the difference between the proton RMS radius and the neutron one is very large. This suggests that there exists a proton halo in 23Al.

Measurements of the total reaction cross sections (sigma (R)) for some proton-rich nuclei (N = 11 - 15 isotones) on a carbon target at intermediate energies have been performed on the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou. A larger enhancement of sigma (R) for P-27 has been observed than for its neighbours. Evidence for a proton halo in P-27 has been revealed in the Glauber analysis of the total reaction cross sections in terms of the difference factor d.

Hard photon emitted from energetic heavy ion collisions is of very interesting since it, does not, experience the late-stage nuclear interaction, therefore it is useful to explore the early-stage information of matter phase. In this work, we ha re, calculated the impact parameter and beam energy dependence for azimuthal asymmetry characterized by directed transverse flow parameter F and elliptic asymmetry coefficient nu 2, of direct photons and the corresponding free protons in intermediate energy heavy-ion collisions. It is further shown the anti-correlated azimuthal asymmetry between direct, photons and free protons.

Using an isospin-dependent quantum molecular dynamics (IQMD) model, we study the (15)C induced reactions front 30-120 MeV/nucleon systematically. Here the valence neutron of (15)C is assigned at both 1d5/2 and 2s1/2 states respectively in order to study the density effect of reaction mechanism. It is believed that the existent neutron halo structure at the 2s1/2 state of (15)C will affect the light particle emission evidently. In our calculation, the different density distributions of (15)C at two states are calculated by relativistic mean field (RMF) model and introduced in the initiation of IQMD model, respectively. It is found that some observables such as emission fragmentation multiplicity, emission neutron/proton ratio and emission neutrons' kinetic energy spectrum are sensitive to the initial density distribution.

Total reaction cross sections sigma (R) for some proton-rich isotones (N = 10) near Al-23 on a carbon target have been measured at intermediate energies in the experiment performed at the Radioactive Ion Beam Line of the Heavy Ion Research Facility in Lanzhou. The Z-dependence Of sigma (R) shows a remarkable enhancement for Al-23 relative to its neighbours. The difference factor d has been deduced from the measured sigma (R) by using the Glauber or Boltzmann-Uehling-Uhlenbeck models. From the above analysis, a possible one-proton halo structure is suggested for Al-23.