Electroproduction of $K^{+}$ mesons along the virtual-photon direction

We report measurements of kaon electroproduction from hydrogen and deuterium targets carried out at the Wilson Synchrotron Laboratory at Cornell University. The reactions ${\gamma }_{V}p\to K^{+}{X}^0$, $K^{+}\Gamma$, and $K^{+}{\Sigma }^0$ were studied in the kinematic region $2.15\le W\le 3.1$ GeV and $1.2<Q^2<4.0$ ${\mathrm{GeV}}^2$ as a function of $Q^2$, $W$, and $\omega$. The $K^{+}{\Sigma }^0$ cross sections fall much more rapidly with increasing $Q^2$ than the $K^{+}\Lambda$ cross sections so that $\frac{K^{+}{\Sigma }^0}{K\Lambda \to 0}$ as $Q^2$ increases.