The mass of the Delta resonance in a finite volume: fourth-order calculation

Understand

We calculate the self-energy of the Delta (1232) resonance in a finite volume, using chiral effective field theory with explicit spin-3/2 fields.

• The calculations are performed up-to-and-including fourth order in the small scale expansion and yield an explicit parameterization of the energy spectrum of the interacting pion-nucleon pair in a finite box in terms of both the quark mass and the box size L.
• It is shown that finite-volume corrections can be sizeable at small quark masses.