Merging the CEM2k and LAQGSM Codes with GEMINI

Abstract

Abstract. An improved version of the Cascade-Exciton Model (CEM) of nuclear reactions contained in the code CEM2k and the Los Alamos version of the Quark-Gluon String Model (LAQGSM) are merged with the well-known sequential-binarydecay model GEMINI by Charity. We present some results on proton-induced fragmentation, fission-product yields and on particle spectra predicted by these extended versions of CEM2k and LAQGSM. We show that merging CEM2k and LAQGSM with GEMINI allows us to describe many fission and fragmentation reactions in addition to the spallation and evaporation reactions which are already described well by these codes. Nevertheless, the current version of GEMINI we use does not provide a completely satisfactory description of some complex-particle spectra, fragment emission, and spallation yields for some reactions, and is not yet a universal tool for applications. Our results show that GEMINI contains a powerful model to describe evaporation/fission/fragmentation reactions and often provides better results when compared to other models, especially for emission of heavy fragments from reactions on medium-heavy nuclei (where most other models simply fail), but it must be further extended and improved in order to properly describe arbitrary reactions.

Quasiparticle-random-phase approximation treatment of the transverse wobbling mode reconsidered

“…Selfconsistency is only locally restored by constructing the residual interaction from the requirement that the resulting HamiltonianĤ =ĥ + V 4qp becomes rotational invariant. Such "symmetry-restoring interaction" [19,20]…”

“…According to Eq. (19) one recognizes that for the selfconsistent deformation (ε, γ) sc the common prefactor in the Hamiltonian (19) becomes equal to κ • /2 and the three ratios of the Sin terms become one. Thus, for the sc deformations the HamiltonianĤ, Eq.…”

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Possible Improvements to MCNP6 and its CEM/LAQGSM Event-Generators

“…5 in Ref. [75]). This means, before implementing the "G" versions of our CEM and LAQGSM event generators in a production version of MCNP6, we have first to fine-tune these two parameters of GEMINI on as many as possible nuclear reactions, at different energies.…”