Abstract
In this paper, the chiral effective field theory is used to investigate the spin singlet channel [Formula: see text], of proton-proton (pp) scattering according to the new suggested power counting. For this purpose, the pp zero scattering amplitude is reproduced by inserting one pion exchange at leading order (LO) and the Coulomb interaction between protons at next-to-leading order (NLO). This leads to a systematic improvement up to NLO compared to the result obtained from Nijm93 potential model.