The two-nucleon problem in EFT reformulated: Pion and nucleon masses as soft and hard scales

TL;DR

This paper reformulates baryon chiral effective field theory for nucleon-nucleon interactions, addressing power counting issues related to nucleon mass and analyzing quark mass effects on scattering lengths and deuteron binding energy.

Contribution

It introduces a modified EFT formulation that treats pion and nucleon masses as separate scales and presents leading-order results for key nucleon-nucleon observables.

Findings

Quark mass dependence of scattering lengths and deuteron energy calculated

Modified power counting scheme addresses nucleon mass issues

Leading order results align with known physical trends

Abstract

We outline the modified formulation of baryon chiral effective field theory for nucleon-nucleon scattering and discuss the issue of a possible power counting violation by the nucleon mass. We also present the results for the quark mass dependence of the $^1S_0$ and $^3S_1$ scattering lengths and the deuteron binding energy at leading order.