Role of the isovector nucleon-nucleus interaction potential in nonmesonic hypernuclear decay

C. BARBERO; A. MARIANO; S.B. DUARTE

PHYS. REV. - C

AMER PHYSICAL SOC

Lugar: New York; Año: 2010 vol. 82 p. 1 - 4

0556-2813

We develop a theoretical finite nucleus framework for the evaluation of the coincidence number of pairs N_nN and the asymmetry parameter a_Lambda in nonmesonic hypernuclear decay Lambda N -> nN, and introduce the effect of final-state interactions. The primary nonmesonic weak hyperon-nucleon decay process is described through the independent-particle shell model. We work within the 2p1h subspace of final states, assuming a simple approach for finite nuclei based on the eikonal approximation. An optical potential including the nucleon-nucleus isoscalar and isovector interactions is introduced to take into account the minimum nuclear-medium effects. The calculated values for 5He and 12 C show that our treatment of final-state interactions, even those considered as restricted to a subspace of states, brings the independent-particle model results closer to the experimental data.