The Quark-Mass Dependence of Two-Nucleon Systems
نویسندگان
چکیده
We explore the quark-mass dependence of two-nucleon systems. Allowed regions for the scattering lengths in the S0 and S1 channels as functions of the light-quark masses are determined from the current uncertainty in stronginteraction parameters that appear at next-to-leading order in the effective field theory. Where experimental constraints are absent, as is the case for the quark-mass dependent four-nucleon operators, we use naive dimensional analysis. We find it likely that there is no bound state in the S0 channel in the chiral limit. However, given the present uncertainties in strong-interaction parameters it is unclear whether the deuteron is bound or unbound in the chiral limit.
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