We report on new H$(e,e^prime p)gamma$ measurements in the $Delta(1232)$ resonance at $Q^2=0.06$ (GeV/c) carried out simultaneously with H$(e,e^prime p)pi^0$. It is the lowest $Q^2$ for which the virtual Compton scattering (VCS) reaction has been studied in the first resonance region. The VCS measured cross sections are well described by dispersion-relation calculations in which the multipole amplitudes derived from H$(e,e^prime p)pi^0$ data are used as input, thus confirming the compatibility of the results. The derived resonant magnetic dipole amplitude $M^{3/2}_{1+} = (40.60 pm 0.70_{stat+sys})(10^{-3}/m_{pi^+})$ at $W=$ 1232 MeV is in excellent agreement with the value extracted from H$(e,e^prime p)pi^0$ measurements.
تحميل البحث