The He-3(mu(-),nu(mu))H-3 weak capture is studied using correlated-hyperspherical-harmonics wave functions, obtained from realistic Hamiltonians consisting of the Argonne v(14) or Argonne v(18) two-nucleon, and Tucson-Melbourne or Urbana-IX three-nucleon interactions. The nuclear weak charge and current operators have vector and axial-vector components with one- and two-body contributions. The axial-vector current includes the nucleon and Delta induced pseudoscalar terms, with coupling constants g(PS) and g(PS)(*) derived from pion-pole dominance and partially conserved-axial-current hypothesis. The strength of the leading two-body operator is adjusted to reproduce the Gamow-Teller matrix element in tritium beta decay. The calculated total capture rate is within similar to0.5% of the most recent measurement, 1496+/-4 sec(-1). The predictions for the capture rate and angular correlation parameters A(v), A(t), and A(Delta) are found to be only very weakly dependent on the model input Hamiltonian. The variation of the observables with g(PS) and g(PS)(*) and the theoretical uncertainties deriving from the model-dependent procedure used to constrain the axial current are investigated.
Theoretical study of He-3(mu(-),nu(mu))H-3 capture RID A-7123-2011
MARCUCCI, LAURA ELISA;
2002-01-01
Abstract
The He-3(mu(-),nu(mu))H-3 weak capture is studied using correlated-hyperspherical-harmonics wave functions, obtained from realistic Hamiltonians consisting of the Argonne v(14) or Argonne v(18) two-nucleon, and Tucson-Melbourne or Urbana-IX three-nucleon interactions. The nuclear weak charge and current operators have vector and axial-vector components with one- and two-body contributions. The axial-vector current includes the nucleon and Delta induced pseudoscalar terms, with coupling constants g(PS) and g(PS)(*) derived from pion-pole dominance and partially conserved-axial-current hypothesis. The strength of the leading two-body operator is adjusted to reproduce the Gamow-Teller matrix element in tritium beta decay. The calculated total capture rate is within similar to0.5% of the most recent measurement, 1496+/-4 sec(-1). The predictions for the capture rate and angular correlation parameters A(v), A(t), and A(Delta) are found to be only very weakly dependent on the model input Hamiltonian. The variation of the observables with g(PS) and g(PS)(*) and the theoretical uncertainties deriving from the model-dependent procedure used to constrain the axial current are investigated.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.