Rb原子吸収線を利用する^ Sr^+イオンポンピング光源

David Husain, Gareth O. Roberts

The kinetics of Ca(4 3PJ), Sr(5 3PJ) and Sr(6 3S1) have been studied by time-resolved emission following pulsed dye-laser excitation. Ground-state calcium atoms, Ca[4s2(1S0)], in the presence of Sr[5s2(1S0)], were optically excited to the first electronically excited state, Ca[4s4p(3P1)], by means of a dye-laser operating at λ= 657.3 nm [Ca(4 3P1)â†� Ca(4 1S0)]. Following rapid Boltzmann equilibration within the Ca(43PJ) manifold, fast, near-resonant energy transfer took place with Sr(5 1S0) to yield Sr(5 3PJ), together with energy pooling to yield Sr(6 3S1). The following transitions were monitored in the time-resolved mode using pre-trigger photomultiplier gating and boxcar integration with repetitive pulsing on a slow-flow system, kinetically equivalent to a static system: Ca(4 3P1)→ Ca(4 1S0)+hν(λ= 657.3 nm), Sr(5 3P1)→ Sr(5 1S0)+hν(λ= 689.3 nm) and Sr(6 3S1)→ Sr(5 3P0)+hν(λ= 679.1 nm). Detailed measurements of the time dependence of the emission profiles at λ= 657.3 and 689.3 nm demonstrated the rapid establishment of the equilibrium Ca(4 3PJ)+ Sr(5 1S0)⇌ Ca(4 1S0)+ Sr(5 3PJ) and its sustenance throughout kinetic decays. A further comparison of the first-order decay coefficients for the decays of Ca(4 3PJ) and Sr(5 3PJ) with those for Sr(6 3S1) demonstrated energy pooling between Ca(4 3PJ)+ Sr(5 3PJ) and Sr(5 3PJ)+ Sr(5 3PJ). Finally, the measured first-order decay coefficients, k′, for Ca(4 3PJ) and Sr(5 3PJ) in chemical equilibrium with one another are seperated quantitatively into their component parts of spontaneous emission, diffusion, the equilibrium constant connecting the 3PJ states and collisional quenching rate constants. Rate constants for quenching of Ca(4 3PJ) and Sr(5 3PJ) by Kr, Xe, H2 and D2 derived from earlier measurements on the individual atoms are found to be quantitatively consistent with the decay profiles under equilibrium conditions.

勲 松田, 近藤 義一, 内武 倉持 +4 more

James Floyd Kelly, Martin A. Harris, Alan C. Gallagher

Energy pooling (EP) has been observed in Sr vapor following pulsed optical excitation to the 5${}^{3}$${P}_{1}$ state. From the time-dependent radiative decay of 6${}^{3}$${S}_{1}$ and of ${6}^{1}$${\mathit{S}}_{0}$ via the cascade resonance line, the EP rate coefficients have been investigated for the following: Sr(5 $^{3}P_{J}$)+Sr(5${}^{3}$${\mathit{P}}_{\mathit{J}\mathcal{'}}$) ${(5}^{1}$${S}_{0}$) +Sr(6 $^{3}S_{1}$ or ${6}^{1}$${S}_{0}$). The values of ${k}_{11}$ have been measured, as well as ${k}_{\mathrm{JJ}\mathcal{'}}$ averaged over a thermal distribution of 5 $^{3}P_{J}$ populations. The time-dependent Sr(${5}^{3}$${P}_{J}$) densities were measured by absorption of lines from a Sr lamp crossing the excitation region. The rate coefficients are surprisingly large; in spite of the small statistical weights of these product states, they are nearly gas-kinetic. The dependence of the rates upon spin, J, and energy defect \ensuremath{\Delta}E has also been examined.

健一 伊賀, 人八 福与

大地 佐藤, 啓吾 鎌田, 陽介 伊藤 +1 more

Dieter Feldmann, J Krautwald, S. L. Chin +2 more

Multiphoton ionisation of strontium atoms to Sr + and Sr 2+ has been investigated with a Nd-YAG laser ( lambda =10642 AA), its second, third and fourth harmonics and a tunable dye laser in a wavelength region around 5321 AA. The power dependence of the Sr + and Sr 2+ production has been obtained. The creation of Sr 2+ is discussed with respect to two models: the simultaneous excitation and elimination of two electrons and a stepwise ionisation via Sr + .