New production channels for light dark matter in hadronic showers

TL;DR

This paper demonstrates that hadronic showers significantly produce secondary dark photons, especially at low masses, impacting existing constraints on light dark matter models by including these new production channels.

Contribution

It introduces a new mechanism for dark photon production in hadronic showers, highlighting its importance and updating existing limits accordingly.

Findings

Secondary dark photon production dominates at low masses.

Dark photons from showers are less energetic than from meson decays.

Updated limits on light dark matter models considering new production channels.

Abstract

Hadronic showers transfer a relevant amount of their energy to electromagnetic subshowers. We show that the generation of "secondary" dark photons in these sub-showers is significant and typically dominates the production at low dark photon masses. The resulting dark photons are however substantially less energetic than the ones originating from mesons decay. We illustrate this point both semi-analytically and through Monte Carlo simulations. Existing limits on vector-mediator scenarios for light dark matter are updated with the inclusion of the new production processes.