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Abstract: The pressure broadening and shift rates for the K D 2 ( ) transition with N2, CH4, C2H6, C3H8, n-C4H10, and the noble gases were obtained for pressures up to 80 Torr and at a temperature of 55°C by means of laser absorption spectroscopy. Additionally, the broadening and shift rates for the Rb D 1 ( ) transition for He, CH4, C2H6, C3H8, and n-C4H10 were obtained using the same techniques and under similar conditions. The K D 2 collisional broadening rate, , for He, Ne, Ar, Kr, Xe, N2, CH4, C2H6, C3H8, and n-C4H10 are 19.84, 8.88, 18.65, 19.17, 22.19, 18.98, 27.78, 27.60, 27.70, and 33.48MHz/Torr, respectively. The uncertainty in the broadening rates is typically less than 2.1%. The corresponding pressure induced shift rates, δ, are 0.52, −2.06, −5.52, −5.42, −7.01, −5.66, −8.38, −8.04, −9.22, and −9.37MHz/Torr with an uncertainty of less than 1.8%. The Rb D 1 collisional broadening rates for He, CH4, C2H6, C3H8, and n-C4H10 are 20.80, 32.78, 30.49, 33.05, and 29.61 with uncertainties typically less than 2.2%. The collisional shift rates for the Rb D 1 transition are 5.80, −6.96, −7.88, −8.61, and −9.43 with uncertainties on the order of 1.1%. A comparison with the other alkali broadening and shift cross-sections is presented. [Copyright &y& Elsevier]

Abstract: The pressure broadening and shift rates for the potassium ) transition with the noble gases and 3He, H2, HD, D2, N2, CH4, C2H6, C3H8, and n-C4H10 were obtained for pressures up to 80Torr and at a temperature of 55°C by means of laser absorption spectroscopy. The collisional broadening rate, , for He, 3He, Ne, Ar, Kr, Xe, H2, HD, D2, N2, CH4, C2H6, C3H8, and n-C4H10 are 13.08, 17.46, 6.14, 19.45, 16.64, 20.02, 22.15, 19.36, 17.47, 17.78, 29.35, 26.63, 27.27, and 27.85MHz/Torr, respectively. The uncertainty in the broadening rates is typically less than 1.6%. The corresponding pressure induced shift rates, , are 1.63, 6.82, −1.27, −6.44, −5.42, −6.54, −5.34, −5.10, −4.70, −6.80, −7.41, −8.32, −8.59, and −8.80MHz/Torr with a uncertainty of less than 2.4%. A comparison with the other alkali D 1 broadening cross-sections is presented. [Copyright &y& Elsevier]

• Observed broadening, shift, and asymmetry rates for the Cs 6 2 P 1 / 2 → 9 2 S 1 / 2 and 5 2 D 5 / 2 → 10 2 F 5 / 2 , 7 / 2 line shapes with He, Ar, and CH 4. • The observed broadening rates are the largest in the alkali-collision partner literature, with values from 100 to 700 MHz/Torr. • The observed shift rates for 5 2 D 5 / 2 → 10 2 F are the largest in the alkali-collision partner literature, with absolute values from 100 to 270 MHz/Torr. • The direction of the shift and asymmetry are correlated in all cases, with a blue shift for He and red shifts for Ar and CH 4. • The collisional cross section scales linearly with polarizability of the collision partner. Pump modulated laser absorption spectroscopy was used to measure the cesium 6 2 P 1 / 2 → 9 2 S 1 / 2 and 5 2 D 5 / 2 → 10 2 F 5 / 2 , 7 / 2 line shapes with helium, argon, and methane used as collision partners. The broadening rates are 99.5 ± 3.4, 116.6 ± 1.8, 188.2 ± 3.3, 133.2 ± 1.2, 294 ± 4.5, and 710 ± 18 MHz/Torr for He, Ar, and CH 4 in 6 P − 9 S and 5 D − 10 F respectively, while the shift rates are +121 ± 21, - 29.3 ± 21, - 61 ± 16, +101.4 ± 0.8, - 273.0 ± 8.0, and - 231 ± 29 MHz/Torr. For those same transitions, the asymmetry rates are +0.18 ± 0.15, - 3.1 ± 0.14, - 3.2 ± 0.1, +0.14 ± 0.04, and - 0.32 ± 0.22 mrad/Torr, with no reported value for CH 4 along 5 D − 10 F. Broadening rates scale as expected with polarizability, shift direction is to the blue/red with He/other gases, and the direction of the asymmetry correlates to the shift. [ABSTRACT FROM AUTHOR]