The solar proton burning process revisited in chiral perturbation theory

The proton burning process p + p --> d + e(+) + nu(e), important for the st ellar evolution of main-sequence stars of mass equal to or less than that o f the Sun, is computed in effective field theory by means of chiral perturb ation expansion to the next to next to leading chiral order. This represent s a model-independent calculation consistent with low-energy effective theo ry of QCD comparable in accuracy to the radiative np capture at thermal ene rgy previously calculated by first using very accurate two-nucleon wave fun ctions backed up by an effective held theory technique with a finite cutoff . The result obtained thereby is found to support within theoretical uncert ainties the previous calculation of the same process by Bahcall and his cow orkers.