D.N. Basu

Role of effective interaction in nuclear disintegration processes

Abstract A simple superasymmetric fission model using microscopically calculated nuclear potentials has shown itself to be outstandingly successful in describing highly asymmetric spontaneous disintegration of nuclei into two composite nuclear fragments. The nuclear interaction potentials required to describe these nuclear decay processes have been calculated by double folding the density distribution functions of the two fragments with a realistic effective interaction. The microscopic nucleus–nucleus potential thus obtained, along with the Coulomb interaction potential and the minimum centrifugal barrier required for the spin-parity conservation, has been used successfully for the lifetime calculations of these nuclear disintegration processes.

Folding model analysis of proton radioactivity of spherical proton emitters

Half-lives of the decays of spherical nuclei away from the proton drip line by proton emissions are estimated theoretically. The quantum mechanical tunneling probability is calculated within the WKB approximation. Microscopic proton-nucleus interaction potentials are obtained by single folding the densities of the daughter nuclei with M3Y effective interaction supplemented by a zero-range pseudopotential for exchange along with the density dependence. Parameters of the density dependence are obtained from the nuclear matter calculations. Spherical charge distributions are used for Coulomb interaction potentials. These calculations provide reasonable estimates for the observed proton-radioactivity lifetimes of proton-rich nuclei for proton emissions from 26 ground and isomeric states of spherical proton emitters.

The density dependence and the range of effective projectile-nucleon interaction from optical model analysis

Abstract The relations between the geometries of density distributions and potentials obtained by folding these with density dependent forces have been used to obtain empirical estimates of the range and the density dependence of effective proton-, deuteron-, helion-, and alpha- nucleon interactions, from best fit phenomenological optical potentials available in literature, for these projectiles.

Nuclear equation of state at high baryonic density and compact star constraints

Abstract A mean field calculation is carried out to obtain the equation of state (EoS) of nuclear matter from a density-dependent M3Y interaction (DDM3Y). The energy per nucleon is minimized to obtain ground state of the symmetric nuclear matter (SNM). The constants of density dependence of the effective interaction are obtained by reproducing the saturation energy per nucleon and the saturation density of SNM. The energy variation of the exchange potential is treated properly in the negative energy domain of nuclear matter. The EoS of SNM, thus obtained, is not only free from the superluminosity problem but also provides excellent estimate of nuclear incompressibility. The EoS of asymmetric nuclear matter is calculated by adding to the isoscalar part, the isovector component of M3Y interaction. The SNM and pure neutron matter EoS are used to calculate the nuclear symmetry energy which is found to be consistent with that extracted from the isospin diffusion in heavy-ion collisions at intermediate energies. The β equilibrium proton fraction calculated from the symmetry energy and related theoretical findings are consistent with the constraints derived from the observations on compact stars.

An α-nucleus optical potential using a realistic effective interaction

Abstract The real part of the α-nucleus optical potential has been computed, the direct part by folding in the two density distribution functions and the exchange part by folding in the two density matrices with the finite-range M3Y and Paris two-body effective interactions. The exchange part turns out to be both density and energy dependent. The potentials reproduce the elastic α-scattering data from 40 Ca, 50 Ti, 52 Cr, 58 Ni and 208 Pb successfully.

Higher-order symmetry energy of nuclear matter and the inner edge of neutron star crusts

The parabolic approximation to the equation of state of the isospin asymmetric nuclear matter (ANM) is widely used in the literature to make predictions for the nuclear structure and the neutron star properties. Based on the realistic M3Y-Paris and M3Y-Reid nucleon-nucleon interactions, we investigate the effects of the higher-order symmetry energy on the proton fraction in neutron stars and the location of the inner edge of their crusts and their core-crust transition density and pressure, thermodynamically. Analytical expressions for different-order symmetry energy coefficients of ANM are derived using the realistic interactions mentioned above. It is found that the higher-order terms of the symmetry energy coefficients up to its eighth-order (E

Folding model analysis of proton scattering from mirror nuclei 18Ne and 18O

_{sym8}

Isobaric incompressibility of isospin asymmetric nuclear matter

) contributes substantially to the proton fraction in

Coulomb-nuclear interference in 56 MeV deuteron breakup at extreme forward angle

\beta

Mass dependence of the real optical model potential for light ions

stable neutron star matter at different nuclear matter densities, the core-crust transition density and pressure. Even by considering the symmetry energy coefficients up to E