6533b873fe1ef96bd12d4c02
RESEARCH PRODUCT
A theoretical approach to pionic atoms and the problem of anomalies
Eulogio OsetCarmen Garcia-recioJuan Nievessubject
PhysicsNuclear and High Energy PhysicsIsospinQuantum electrodynamicsQuantum mechanicsPolarization (waves)Optical potentialdescription
Abstract We have constructed a theoretical optical potential for pionic atoms based on the first- and second-order terms of a many-body expansion on the number of ph excitations. The p-wave parts are very much influenced by the medium polarization. The quenching at large densities produced by this phenomenon, together with the one from the Lorentz-Lorenz effect, and modifications over standard potentials due to the isospin dependence, lead to a new potential which produces notoriously improved results in the problem of anomalies. A clearer definition of this problem is proposed as the inability of standard potentials to reproduce simultaneously the data for light and heavy nuclei. Finally a semiphenomenological potential is obtained by adding some small terms to the theoretical potential which are fitted to the data and by means of which a good overall fit to the data is obtained. This potential is then used to make predictions for energies and widths of deeply bound pionic states so far unobserved.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1993-03-01 | Nuclear Physics A |