Abstract
The astrophysical factor for proton-proton weak capture is calculated in chiral effective field theory over the center-of-mass relative-energy range 0–100 keV. The chiral two-nucleon potential derived up to next-to-next-to-next-to leading order is augmented by the full electromagnetic interaction including, beyond Coulomb, two-photon and vacuum-polarization corrections. The low-energy constants entering the weak current operators are fixed so as to reproduce the binding energies and magnetic moments and the Gamow-Teller matrix element in tritium decay. Contributions from and partial waves in the incoming two-proton channel are retained. The factor at zero energy is found to be , with a -wave contribution of . The theoretical uncertainty is due to the fitting procedure of the low-energy constants and to the cutoff dependence.
- Received 13 March 2013
DOI:https://doi.org/10.1103/PhysRevLett.110.192503
© 2013 American Physical Society