Absorption of Light by Potassium Vapor between 2856 and 1150 Å

Abstract

The continuous atomic and molecular cross sections of potassium vapor have been measured using photoelectric techniques from the $4{s}^{2}S\ensuremath{\rightarrow}n{p}^{2}{P}^{0}$ series limit at 2856 to 1150 \AA{}. The bandwidth of the monochromator was 0.75 \AA{} and values of the cross sections were obtained at 2-\AA{} intervals. The value obtained for the atomic absorption cross section at the series limit was 0.010\ifmmode\pm\else\textpm\fi{}0.003 Mb or 0.012\ifmmode\pm\else\textpm\fi{}0.003 Mb, depending on which vapor-pressure formula was used in the analysis of the results. A minimum of 0.002\ifmmode\pm\else\textpm\fi{}0.002 Mb was observed between 2730 and 2600 \AA{}. This latter result disagrees with previous experimental results but is in agreement with theoretical predictions.