ALP Distributions from Hadron Structure

Abstract

We investigate how hadron structure and quark-flavor couplings shape axion-like particle (ALP) radiation in hadron collisions. For the elastic pole, the virtuality integral is ultraviolet finite at fixed momentum fraction if the pseudoscalar form factor falls as a positive power of $1/Q^2$ at large $Q^2$, eliminating the point-particle beam-energy logarithm. Pion-pole and lattice-QCD isovector benchmarks suppress the process-weighted elastic contribution by roughly three orders of magnitude relative to the point-particle result. Two coefficient sets matched to the same leading low-energy nucleon source yield process-weighted resolved leading logarithms differing by four orders of magnitude, demonstrating the sensitivity of resolved ALP radiation to heavy-quark coupling configurations.