Convection Currents and Spin Magnetization in $E2\mathrm{}$ Transitions of ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$

The transverse electromagnetic form factors squared of the ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$ $2^{+}$ levels at 4.439 MeV ($T=0\mathrm{}$) and at 16.107 MeV ($T=1\mathrm{}$) have been measured by means of 180° electron scattering over a momentum-transfer range from $q=0.51\mathrm{} \mathrm{to} 2.05$ ${\mathrm{fm}}^{-1\mathrm{}}$. Evidence is presented for appreciable contributions of nuclear convection currents to the transverse 4.439-MeV form factor at low $q$, and spin magnetization contributions to the transverse 16.107-MeV form factor at higher $q$.