Radiative corrections to superallowed decays in effective field theory
Vincenzo Cirigliano🇺🇸 · Wouter Dekens🇺🇸 · Jordy de Vries🇳🇱 · Stefano Gandolfi🇺🇸 · Martin Hoferichter🇨🇭 · Emanuele Mereghetti🇺🇸
The accuracy of determinations from superallowed decays critically hinges on control over radiative corrections. Recently, substantial progress has been made on the single-nucleon, universal corrections, while nucleus-dependent effects, typically parameterized by a quantity , are much less well constrained. Here, we lay out a program to evaluate this correction from effective field theory (EFT), highlighting the dominant terms as predicted by the EFT power counting. Moreover, we compare the results to a dispersive representation of and show that the expected momentum scaling applies even in the case of low-lying intermediate states. Our EFT framework paves the way towards ab-initio calculations of and thereby addresses the dominant uncertainty in .