J\"ulich-Bonn-Washington Model for Pion Electroproduction Multipoles

Pion electroproduction off the proton is analyzed in a new framework based on a general parametrization of transition amplitudes, including constraints from gauge invariance and threshold behavior. Data with energies $1.13~{\rm GeV}<W<1.6~{\rm GeV}$and$Q^2$below$6~{\rm GeV}^2$ are included. The model is an extension of the latest J"ulich-Bonn solution incorporating constraints from pion-induced and photoproduction data. Performing large scale fits ($\sim {10}^5$ data) we find a set of solutions with ${\chi }_{\mathrm{d}\mathrm{o}\mathrm{f}}^2=1.69-1.81$ which allows us to assess the systematic uncertainty of the approach.