Congratulations to Tony Thomas for getting a paper published in the Journal of High Energy Physics

The existence of dark matter has been firmly established from its gravitational interactions, yet its precise nature continues to elude us despite the best efforts of physicists around the world. The key to understanding this mystery could lie with the dark photon, a theoretical massive particle that may serve as a portal between the dark sector of particles and regular matter. In our recent work, a collaboration between CSSM, the Adelaide node of the ARC Centre of Excellence for Dark Matter Particle Physics and Jefferson Laboratory, we study the potential effects a dark photon could have on the interpretation of existing experimental results from the deep inelastic scattering process. Specifically, we make use of the state-of-the-art Jefferson Angular Momentum collaboration (JAM) global analysis framework for parton distribution functions, modifying the underlying theory to allow for the effect of a dark photon. We show that the dark photon hypothesis is preferred over the Standard Model hypothesis at a significance of 6.5 sigma, which constitutes strong evidence, albeit indirect, for a particle discovery.

Profile likelihood showing preferred regions for the dark photon mass and mixing parameter. This suggests that the Standard Model is disfavoured at 6.5σ.