A general approach to quantum integration of cross sections in high-energy physics

Abstract: We present universal \emph{building blocks} for the quantum integration of generic cross sections in high-energy physics. We make use of Fourier Quantum Monte Carlo Integration as implemented in {\sc Quantinuum}'s Quantum Monte Carlo Integration engine to provide an extendable methodology for generating efficient circuits that can implement generic cross-section calculations, providing a quadratic speed-up in root mean-squared error convergence with respect to classical Monte Carlo integration. We focus on a concrete example of a $1\to 3$ decay process to illustrate our work.