Calculation of doublet capture rate for muon capture in deuterium within chiral effective field theory

The doublet capture rate Lambda(1/2) of the negative muon capture in deuterium is calculated employing the nuclear wave functions generated from accurate nucleon-nucleon (NN) potentials constructed at next-to-next-to-next-to-leading order of heavy-baryon chiral perturbation theory and the weak meson exchange current operator derived within the same formalism. All but one of the low-energy constants that enter the calculation were fixed from pion-nucleon and nucleon-nucleon scattering data. The low-energy constant (d) over cap (R) (c(D)). which cannot be determined from the purely two-nucleon data, was extracted recently from the triton beta-decay and the binding energies of the three-nucleon systems. The calculated values of Lambda(1/2) show a rather large spread for the used values of the (d) over cap (R). Precise measurement of Lambda(1/2) in the future will not only help to constrain the value of (d) over cap (R), but also provide a highly nontrivial test of the nuclear chiral EFT framework. Besides, the precise knowledge of the constant (d) over cap (R) will allow for consistent calculations of other two-nucleon weak processes, such as proton-proton fusion and solar neutrino scattering on deuterons, which are important for astrophysics. (C) 2012 Elsevier B.V. All rights reserved.