Measurements of the neutron electric to magnetic form factor ratioGEn/GMnvia theH2(e→,e'n→)H1reaction toQ2=1.45(GeV/c)2

We report values for the neutron electric to magnetic form factor ratio, $G_{\mathit{En}}/G_{\mathit{Mn}}$, deduced from measurements of the neutron's recoil polarization in the quasielastic ${}^2\mathrm{H}$ $(\overrightarrow{e},e^{\text{'}}\overrightarrow{n})$ ${}^1\mathrm{H}$ reaction, at three $Q^2$ values of 0.45, 1.13, and 1.45 (GeV/c)${}^2$. The data at $Q^2=1.13$ and 1.45 (GeV/c)${}^2$ are the first direct experimental measurements of $G_{\mathit{En}}$ employing polarization degrees of freedom in the $Q^2>1$ (GeV/c)${}^2$ region and stand as the most precise determinations of $G_{\mathit{En}}$ for all values of $Q^2$.