Exclusive $\pi^{-}$ Electroproduction off the Neutron in Deuterium in the Resonance Region

We report new results for the exclusive and quasi-free cross sections off neutrons bound in deuterium ${\gamma}^{\ast}n(p) \rightarrow p{\pi}^{-} (p)$, which are presented over a wide final hadron angle range with a kinematic coverage of the invariant mass ($W$) up to $1.825\;\text{GeV}$ and the virtual photon four-momentum squared ($Q^{2}$) from $0.4$ to $1.0 \; \text{GeV}^{2}$. The experimental data were collected with the CLAS detector in Hall B at Jefferson Laboratory. The exclusive structure functions have been extracted and their Legendre moments were obtained. The exclusive quasi-free process has been kinematically isolated as successfully demonstrated by the comparison of the spectator momentum distribution of the simulation with the missing momentum distribution of the data. Accordingly final-state-interaction contributions could be separated from the extracted quasi-free cross sections off bound neutrons solely based on the analysis of the experimental data. These new results will serve as long-awaited input for phenomenological analyses to extract the $Q^{2}$ evolution of previously unavailable n $\rightarrow \text N^{*}$ electroexcitation amplitudes and to improve state-of-the-art models of neutrino scattering off nuclei by augmenting the already available results from free protons.