Polarization of Resonance Radiation in Mercury

Abstract

$1{}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}-2\mathrm{}{}_{}{}^3{}_{}{}^{}P_1^{}{}_{}{}^{}$ of mercury excited by plane polarized light shows incomplete polarization both in the absence and in the presence of a weak field parallel to the electric vector. The amount of initial polarization depends upon the relative intensities of the hyperfine structure lines in the exciting light. The polarization with various relative orientations of field and light vector and the variation of polarization with field intensity in weak fields may be interpreted successfully by means of a semi-classical model, with proper relative intensities parallel and prependicular to the light vector, rotating after excitation with an angular velocity $\frac{\mathrm{geH}}{2mc}$ and emitting a damped wave. From curves connecting depolarization, rotation of maximum of polarization, etc., with field intensity $\alpha$, the damping constant, has been found to be 1.02 (±0.02) ${10}^7$ ${\sec }^{-1\mathrm{}}$.