Experimental Determination of the Current Density of theH (n=3)State Produced in Electron-Transfer Collisions ofH+on He

Four signals characterizing the Balmer-alpha radiation resulting from 40-80-keV collisions of ${\mathrm{H}}^{+}$ on He were measured as a function of an applied transverse electric field. Detailed analysis allowed the axially symmetric density matrix of the $\mathrm{H} \mathrm{}(n=3\mathrm{})\mathrm{}$ atom formed in the collision to be obtained. The imaginary parts of the off-diagonal density-matrix elements are presented as the distribution of the electronic current density in the atom. One of the first-order moments ${〈\overrightarrow{\mathrm{A}}\times \overrightarrow{\mathrm{L}}〉}_z^s$ of the current distribution is given.