- The paper updates constraints on hidden photons by reanalyzing data from KEK and Orsay electron beam dump experiments.
- It employs detailed Monte Carlo simulations to calculate experimental acceptances and refine upper limits on photon production.
- The findings link hidden photons to dark radiation anomalies and muon magnetic moment deviations, guiding future experimental searches.
Limits on Hidden Photons from Electron Beam Dump Experiments
The paper titled "New limits on hidden photons from past electron beam dumps" explores constraints on hidden photons, which represent an extension of the Standard Model (SM) and are a notable feature in theories such as string theory and supersymmetry. Hidden photons are U(1) gauge bosons that interact weakly with the SM particles through kinetic mixing with the ordinary photon. This paper specifically focuses on examining past electron beam dump experiments to establish updated constraints for hidden photons in the parameter space defined by their mass and kinetic mixing parameter.
The authors recount the theoretical motivation for hidden photons, emphasizing their potential to address discrepancies in astrophysical observations. They discuss two significant mass ranges where hidden photons might influence physical phenomena: the meV to GeV scale where hidden photons could explain the observed excess in dark radiation and the deviation in the muon's anomalous magnetic moment, respectively.
The paper methodically revisits several historic electron beam dump experiments, including those conducted at KEK in Japan and Orsay in France, which had not previously been analyzed for hidden photons. By employing detailed Monte Carlo simulations, the authors calculate experimental acceptances and thereby refine the upper limits on the production and detection of these particles. The updated constraints are depicted in exclusion plots, highlighting regions of the parameter space that are tightly bound by these experimental results. Specifically, the analyses suggest that constraints from the KEK and Orsay experiments fill a previously unconstrained area of the parameter space.
Beyond these electron beam dump experiments, the paper places the derived limits within a broader landscape of constraints from various experiments and observations. This includes previous analyses from SLAC and Fermilab experiments, results from fixed-target experiments, and cosmological data. The comprehensive assessment underscores that while substantial regions of the hidden photon parameter space have been excluded, significant areas remain unexplored and could be targeted by forthcoming experimental efforts.
The implications of these results underscore the importance of considering hidden photons in the search for physics beyond the SM, particularly in the context of dark matter and dark forces. The potential for hidden photons to explain various astrophysical and cosmological anomalies provides a compelling incentive for continued experimental investigation. Future experiments with increased sensitivity and novel methodologies may probe deeper into the parameter space, potentially unveiling new physics linked to hidden photons or other exotic phenomena.
In summary, this work contributes substantially to the ongoing effort to delineate the characteristics and constraints of hidden photons, enhancing our understanding of these hypothetical particles and their role in the universe. The results also pave the path for future explorations and set a framework for integrating findings from various experimental approaches in the quest to test the viability of new physics scenarios at low energies.