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arXiv · 1009.4016

Muon capture on light nuclei

L. E. Marcucci·M. Piarulli
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Abstract

This work investigates the muon capture reactions 2H(μ^-,ν_μ)nn and 3He(μ^-,ν_μ)3H and the contribution to their total capture rates arising from the axial two-body currents obtained imposing the partially-conserved-axial-current (PCAC) hypothesis. The initial and final A=2 and 3 nuclear wave functions are obtained from the Argonne v_{18} two-nucleon potential, in combination with the Urbana IX three-nucleon potential in the case of A=3. The weak current consists of vector and axial components derived in chiral effective field theory. The low-energy constant entering the vector (axial) component is determined by reproducting the isovector combination of the trinucleon magnetic moment (Gamow-Teller matrix element of tritium beta-decay). The total capture rates are 393.1(8) s^{-1} for A=2 and 1488(9) s^{-1} for A=3, where the uncertainties arise from the adopted fitting procedure.

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L. E. Marcucci, M. Piarulli. 2010-09-21. Muon capture on light nuclei. https://doi.org/10.1007/s00601-010-0157-x

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