6533b850fe1ef96bd12a835f
RESEARCH PRODUCT
Lower bound on the proton charge radius from electron scattering data
Vladimir PascalutsaFranziska Hagelsteinsubject
PhysicsNuclear and High Energy PhysicsProtonNuclear Theory010308 nuclear & particles physicsScattering530 PhysicsMomentum transferExtrapolationFOS: Physical sciencesCharge densityRadius01 natural sciencesUpper and lower boundslcsh:QC1-999Nuclear Theory (nucl-th)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Charge radius0103 physical sciencesNuclear Experiment (nucl-ex)Atomic physics010306 general physicsNuclear Experimentlcsh:Physicsdescription
The proton charge-radius determinations from the electromagnetic form-factor measurements in electron-proton scattering require an extrapolation to zero momentum transfer ($Q^2=0$) which is prone to model-dependent assumptions. We show that the data at finite momentum transfer can be used to establish a rigorous lower bound on the proton charge radius. Using the available $ep$ data at low $Q^2$, we obtain $R_E > 0.850(1)$ fm as the lower bound on the proton radius. This reaffirms the discrepancy between the $ep$ and muonic-hydrogen values, while bypassing the model-dependent assumptions that go into the fitting and extrapolation of the $ep$ data.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2019-10-01 |