Collision broadening and shift of the potassium4p−nsand4p−ndlines by argon

A two-step laser excitation technique was used to investigate the collisional broadening and shift of excited-state potassium transitions. Measurements were also made to determine that the broadening and shift constants were unaffected by optical pumping and saturation effects. Values for the argon collisional-broadening and shift constants for the potassium $4p\ensuremath{-}\mathrm{ns} (n=8\ensuremath{-}11)$ and $4p\ensuremath{-}\mathrm{nd} (n=6\ensuremath{-}9)$ transitions were determined from line-shape measurements. The values of these constants (in units of ${10}^{\ensuremath{-}9}$ rad ${\mathrm{s}}^{\ensuremath{-}1}$ ${\mathrm{atom}}^{\ensuremath{-}1}$ ${\mathrm{cm}}^{3}$ at 110\ifmmode^\circ\else\textdegree\fi{}C) and their one-sigma statistical uncertainties are ${({4P}_{\frac{1}{2}}\ensuremath{-}{8S}_{\frac{1}{2}}): \ensuremath{\gamma}=17.03\ifmmode\pm\else\textpm\fi{}0.15, \ensuremath{\beta}=\ensuremath{-}14.58\ifmmode\pm\else\textpm\fi{}0.29 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{8S}_{\frac{1}{2}}): \ensuremath{\gamma}=17.45\ifmmode\pm\else\textpm\fi{}0.24, \ensuremath{\beta}=\ensuremath{-}14.71\ifmmode\pm\else\textpm\fi{}0.30 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{9S}_{\frac{1}{2}}): \ensuremath{\gamma}=17.29\ifmmode\pm\else\textpm\fi{}0.15, \ensuremath{\beta}=\ensuremath{-}24.16\ifmmode\pm\else\textpm\fi{}0.15 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{9S}_{\frac{1}{2}}): \ensuremath{\gamma}=17.35\ifmmode\pm\else\textpm\fi{}0.12, \ensuremath{\beta}=\ensuremath{-}24.16\ifmmode\pm\else\textpm\fi{}0.09 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{10S}_{\frac{1}{2}}): \ensuremath{\gamma}=15.62\ifmmode\pm\else\textpm\fi{}0.07, \ensuremath{\beta}=\ensuremath{-}29.49\ifmmode\pm\else\textpm\fi{}0.22 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{10S}_{\frac{1}{2}}): \ensuremath{\gamma}=15.80\ifmmode\pm\else\textpm\fi{}0.11, \ensuremath{\beta}=\ensuremath{-}29.86\ifmmode\pm\else\textpm\fi{}0.27 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{11S}_{\frac{1}{2}}): \ensuremath{\gamma}=12.69\ifmmode\pm\else\textpm\fi{}0.09, \ensuremath{\beta}=\ensuremath{-}33.66\ifmmode\pm\else\textpm\fi{}0.11 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{11S}_{\frac{1}{2}}): \ensuremath{\gamma}=12.85\ifmmode\pm\else\textpm\fi{}0.17, \ensuremath{\beta}=\ensuremath{-}35.10\ifmmode\pm\else\textpm\fi{}0.23 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{6D}_{\frac{3}{2}}): \ensuremath{\gamma}=13.75\ifmmode\pm\else\textpm\fi{}0.27, \ensuremath{\beta}=\ensuremath{-}8.28\ifmmode\pm\else\textpm\fi{}0.16 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{6D}_{\frac{5}{2}}): \ensuremath{\gamma}=15.15\ifmmode\pm\else\textpm\fi{}0.41, \ensuremath{\beta}=\ensuremath{-}8.96\ifmmode\pm\else\textpm\fi{}0.10 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{7D}_{\frac{3}{2}}): \ensuremath{\gamma}=18.60\ifmmode\pm\else\textpm\fi{}0.21, \ensuremath{\beta}=\ensuremath{-}16.00\ifmmode\pm\else\textpm\fi{}0.18 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{7D}_{\frac{5}{2}}): \ensuremath{\gamma}=19.64\ifmmode\pm\else\textpm\fi{}0.25, \ensuremath{\beta}=\ensuremath{-}15.16\ifmmode\pm\else\textpm\fi{}0.21 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{8D}_{\frac{3}{2}}): \ensuremath{\gamma}=19.94\ifmmode\pm\else\textpm\fi{}0.09, \ensuremath{\beta}=\ensuremath{-}24.14\ifmmode\pm\else\textpm\fi{}0.22 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{8D}_{\frac{5}{2}}): \ensuremath{\gamma}=19.80\ifmmode\pm\else\textpm\fi{}0.06, \ensuremath{\beta}=\ensuremath{-}24.16\ifmmode\pm\else\textpm\fi{}0.18 ;}{({4P}_{\frac{1}{2}}\ensuremath{-}{9D}_{\frac{3}{2}}): \ensuremath{\gamma}=17.40\ifmmode\pm\else\textpm\fi{}0.13, \ensuremath{\beta}=\ensuremath{-}30.17\ifmmode\pm\else\textpm\fi{}0.28 ;}{({4P}_{\frac{3}{2}}\ensuremath{-}{9D}_{\frac{5}{2}}): \ensuremath{\gamma}=17.50\ifmmode\pm\else\textpm\fi{}0.27, \ensuremath{\beta}=\ensuremath{-}29.47\ifmmode\pm\else\textpm\fi{}0.12 .}$ The overall accuracy of these measurements is estimated to be about 5%.