Long-range electroweak amplitudes of single hadrons from Euclidean finite-volume correlation functions

Understand

A relation is presented between single-hadron long-range matrix elements defined in a finite Euclidean spacetime, and the corresponding infinite-volume Minkowski amplitudes.

• This relation is valid in the kinematic region where any number of two-hadron states can simultaneously go on shell, so that the effects of strongly-coupled intermediate channels are included.
• These channels can consist of non-identical particles with arbitrary intrinsic spins.
• The result accommodates general Lorentz structures as well as non-zero momentum transfer for the two external currents inserted between the single-hadron states.