X17 Discovery Potential in the γN→e^{+}e^{-}N Process at Electron Scattering Facilities.

Area of Science:

• Particle Physics
• Nuclear Physics
• High Energy Physics

Background:

• The ATOMKI ^{8}Be and ^{4}He anomalies suggest the existence of a new light particle, the X17 particle.
• Existing experimental data provides constraints on the properties of the hypothetical X17 particle.

Purpose of the Study:

• To propose a direct search strategy for the X17 particle.
• To investigate the dilepton photoproduction process as a viable method for X17 detection.
• To evaluate the feasibility of detecting the X17 particle within specific quantum number scenarios.

Main Methods:

• Direct search for the X17 particle via dilepton photoproduction on a nucleon.
• Analysis of the photon energy range below or around the pion production threshold.
• Estimation of the X17 signal process for pseudoscalar, vector, and axial-vector quantum number scenarios using existing constraints.

Main Results:

• A signal-to-background ratio of up to an order of magnitude is achievable.
• The proposed method is particularly effective for neutron targets.
• The pseudoscalar and vector X17 scenarios show promising signal-to-background ratios.

Conclusions:

• Direct dilepton photoproduction offers a promising avenue for the direct search of the X17 particle.
• The proposed search strategy is sensitive to specific X17 particle properties, particularly for pseudoscalar and vector scenarios.
• Experimental conditions similar to previous experiments could yield significant results.