43 research outputs found
Field and phenomenological description of absorption of particles
The complicated processes in the medium (decays, reactions and
conversion) involving final state absorption are considered. The calculations
in the framework of field and phenomenological approaches are compared. The
reasons for disagreement are studied. The field approach can tend to increase
of total process probability as well as probability of channel corresponding to
absorption, in comparison with phenomenological model.Comment: 5 pages, 1 fige
On the multistep processes in the nuclei
The intermediate-state interaction and structure of amplitudes of complicated
processes in medium (decays, reactions and the transitions) are
studied. It is proposed to use the branching ratio of channels of free-space
hadron-nucleon interaction as a test in the construction and verification of
the models. The corresponding formulas for the processes in the medium are
obtained. The connection between particle self-energy and amplitudes of
subprocesses are analyzed as well.Comment: 5 page
Absorption in the final state in reactions and decays in the medium
The role of strong absorption of particles in intermidiate and final states has been considered. The range of applicability of phenomenological model of absorption has been studied. This model is nonuniversal. Its applicability depends on the type of interaction Hamiltonian and matrix element used. We also demonstrate that the violation of the unitarity condition can produce a qualitative error in the results. The absorption (decay) in the final state does not tend to suppress the total process probability as well as the probability of the channel corresponding to absorption. This is true for the reactions, decays and conversion in the medium