α scattering cross sections on C12 with a microscopic coupled-channels calculation

Abstract

α elastic and inelastic scattering on 12 C is investigated with the coupled-channel calculation using microscopic α-12 C potentials, which are derived by folding the Melbourne g-matrix N N interaction with the matter and transition densities of 12 C. These densities are obtained by a microscopic structure model of the antisymmetrized molecular dynamics combined with and without the 3α generator coordinate method. The calculation reproduces satisfactorily well the observed elastic and inelastic cross sections at incident energies of Eα = 130 MeV, 172.5 MeV, 240 MeV, and 386 MeV with no adjustable parameter. Isoscalar monopole and dipole excitations to the 0 + 2 , 0 + 3 , and 1 − 1 states in the α scattering are discussed.

Probing negative-parity states of Mg24 probed with proton and α inelastic scattering

“…This method has been applied for structural studies of various nuclei including 12 C and neutron-rich Be isotopes [36,45,46], and has also been used in the MCC+AMD calculation for reaction studies of proton and α scattering in Refs. [38][39][40][41][42]. The calculational procedures of the present structure and reaction calculations are almost the same as the MCC+AMD calculation for 20 Ne in Ref.…”

“…The effective nuclear interactions used in the present AMD calculation are the same as those in Refs. [36,[38][39][40][41]; they are the MV1 (case 1) central force [47] with the parameters (b, h, m) = (0, 0, 0.62) and the spin-orbit term of the G3RS force [48,49] with strength parameters u I = −u II = 3000 MeV. The Coulomb force is also included.…”

“…The Melbourne g matrix is an effective NN interaction derived from a bare NN interaction of the Bonn B potential [60]. It contains energy and density dependencies with no adjustable parameter, and can be well applied to a systematic description of elastic and inelastic proton scattering off various nuclei at energies of E p = 40-300 MeV [40][41][42]44,50,56,58] and also of elastic and inelastic α scattering at energies of E α = 100-400 MeV [38,39,41,42,59,61]. In the present reaction calculation, the spin-orbit term of the proton-nucleus potential is not account for to avoid complexity, as in Refs.…”

“…In the MCC calculations, the diagonal and transition densities of the target nuclei obtained with microscopic structure models are utilized as inputs of the CC reaction calculations in microscopic folding models, wherein the nucleon-nucleus and α-nucleus potentials are constructed by folding the effective NN interactions. In our previous studies [38][39][40][41][42][43], we have applied the MCC calculations to proton and α scattering off various target nuclei in the p-and sd-shell regions using the AMD densities and the Melbourne g-matrix NN interaction [44]. We have presented successful results of the MCC+AMD approach for the (p, p ) and (α, α ) cross sections of various excited states.…”

\(\alpha \) Inelastic Scattering Cross Sections Off 12C with Microscopic Coupled-channel Calculation

“…For details of the structure calculation of 12 C, the reader is referred to Refs. [6,7]. We calculate the matter and transition densities of 12 C with the AMD+GCM wave functions to utilize the coupled-channel calculation of the α scattering.…”