Dark photon production via inelastic proton bremsstrahlung with Pauli form factor

TL;DR

This paper investigates dark photon production in proton-proton collisions, emphasizing the role of the Pauli form factor and new splitting functions, which significantly impact sensitivity estimates for future experiments.

Contribution

It introduces the inclusion of the Pauli electromagnetic form factor and two new splitting functions in dark photon production calculations, enhancing the accuracy of sensitivity predictions.

Findings

Pauli form factor can dominate in certain mass ranges

Updated sensitivity estimates for the SHiP experiment

New splitting functions significantly affect production rates

Abstract

We study the production of vector portal mediators, dark photons, with masses in the range 0.4--1.8\,GeV in proton-proton collisions via the process of inelastic proton bremsstrahlung. In contrast to previous studies, we take into account the contribution of Pauli electromagnetic form factor to differential cross section and introduce two new splitting functions of the proton. We show that their contributions can become leading in the mass region 0.9--1.8\,GeV and present the updated estimate for the sensitivity of the future SHiP experiment to visible decays of dark photons.