Pressure broadening and shift of the rubidium D 1 transition and potassium D 2 transitions by various gases with comparison to other alkali rates.

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]