Proton-proton fusion in effective field theory to fifth order

The proton-proton fusion process pp --> de(+)v(e) is calculated at threshol d to fifth order in pionless effective field theory. There are two unknown two-body currents contributing at the second and fourth orders. Combined wi th the previous results for v(e)d and (v) over bar (e)d scattering, compute d to third order in the same approach, we conclude that a similar to 10% me asurement of reactor ed scattering measurement could constrain the pp --> d e(+) v(e) rate to similar to7% while a similar to3% measurement of v(e)d -- > e(-)pp could constrain the pp rate to similar to 2%. (C) 2001 Published b y Elsevier Science B.V.