Measurement of single- and double-polarization observables in the photoproduction of $π^+π^-$~meson pairs off the proton using CLAS at Jefferson Laboratory - Roy, P.; Cao, S.; Crede, V.; Klempt, E.; Nikonov, V. A.; Sarantsev, A. V.; Burkert, V. D.; Mokeev, V.; Achenbach, P.; Alvarado, J. S.; Armstrong, W. R.; Atac, H.; et al. (2025)