Ingoing-wave boundary condition versus optical model transmission coefficients: A systematic comparison with particle emission data

Abstract

Evaporative' ' H and He yields and energy spectra have been analyzed in the framework of the statistical model in ten heavy-ion reactions, spanning composite systems with 20 & Z & 56. Transmission coefficients derived from the ingoing-wave boundary condition (IWBCM) or optical models (OM) have been used in the calculations. The effect of using different values of deformation parameters, level-density parameter a, and radii of the real part of the transmission coefficient potentials has been investigated. Except for the low-energy side of the proton spectra, the shape of energy spectra are reasonably well reproduced by both sets of transmission coefficients. While the two models are essentially equivalent for H and He cross sections, they differ significantly in the prediction of H and H cross sections. OM transmission coefficients fail in reproducing ' H cross sections, unless no standard parameters are used, while IWBCM transmission coefficients provide a good overall agreement. The failure of the OM is ascribed to the inclusion of nonfusion reactions in the inverse process. PACS number(s): 25.70.Gh, 25.70.Jj

Systematic description of evaporation spectra for light and heavy compound nuclei

“…Comparisons of statistical-model predictions with IBWC and standard optical-model value of T ℓ are made in Ref. [20,46] where the biggest differences are associated with deuteron and triton spectra;…”

Intermediate-mass fragment production in spallation reactions

“…However, if the emitted particle is a proton or an alpha, the barrier seems to be overestimated. This problem was already discussed in the past and never solved [10][11][12]. In order to bypass the problem, in case of p and α emission, we used other parameters than those given by Bass.…”

“…The thermal expansion of the compound nucleus [13] is considered. The inverse cross section (σ inv ) was calculated using the ingoing-wave boundary condition model [12], where only a real potential is used to describe the transmission probability of particles. An analytical approximation to equation (1) was used in order to avoid the numerical calculation of the two integrals, which is rather time-consuming.…”

Deformation in28Si*produced via the16O+Kundu1, Bhattacharya2, Bhattacharya3 et al. 2013Phys. Rev. C

“…An orbiting dinuclear complex is assumed to be more deformed than a fully shape equilibrated CN; this motivated us to look for such enhanced deformation in a 16 O + 12 C dinuclear system at same excitation energies using the LCP spectroscopy technique. In this technique, LCPs, evaporated from the excited composites, are used to study the properties of hot rotating nuclear systems as a function of excitation energy, angular momentum, and deformation [11,[13][14][15][16][17][18][19][20][21][22][23][24][25] using statistical model codes, e.g., CASCADE [26], GANES [27], CACARIZO [28].…”