通过氢气中的转动拉曼散射对汤姆逊散射光谱仪系统进行完全校准。

Flora F, Giudicotti L

Appl Opt. 1987 Sep 15;26(18):4001-8. doi: 10.1364/AO.26.004001.

We describe the complete calibration of a ruby laser-based multipoint Thomson scattering system, performed only by rotational Raman scattering from H(2) and the measurement of the absolute Raman cross section of some rotational transitions suitable for such calibrations. The absolute calibration factors (for n(e) measurements by Thomson scattering) have been measured by observing the Stokes J = 1 ? 3 rotational transition at Deltanu = -587 cm(-1) (lambda = 723.8 nm), with a congruent with4.5% accuracy. The relative calibration (for T(e) measurements) has also been performed by Raman scattering, observing the same line in all the spectral channels. The results agree to within congruent with10% with those obtained by a tungsten lamp and a lock-in detection technique. From a comparison of the results of the two methods, systematic errors on the measured T(e) and n(e) of less than ~10% (for T(e) up to 200 eV) are inferred. The absolute cross section of the rotational Raman transitions at Deltaupsilon = -587 cm(-1) (lambda = 723.8 nm), Deltanu = -354 cm(-1) (lambda = 711.8 nm), and Deltanu = 354 cm(-1) (lambda = 677.6 nm) has also been measured, by comparison with the intensity of the Rayleigh line. Significant deviations from thermal equilibrium population in Raman levels, expected from the possible occurrence of stimulated Raman emission, are not observed. From the measured data the anisotropic polarizability of H(2) at lambda = 694.3 nm was estimated to be gamma = 2.93 x 10(-25) cm(3) +/- 3%. The absolute cross section of the strongest rotational lines of H(2) is also given.

我们描述了基于红宝石激光的多点汤姆逊散射系统的完整校准过程，该校准仅通过H₂的转动拉曼散射以及对一些适用于此类校准的转动跃迁的绝对拉曼截面的测量来完成。通过观测斯托克斯J = 1→3转动跃迁（在Δν = -587 cm⁻¹，λ = 723.8 nm），以约4.5%的精度测量了绝对校准因子（用于通过汤姆逊散射测量电子密度n(e)）。相对校准（用于测量电子温度T(e)）也通过拉曼散射进行，在所有光谱通道中观测同一条谱线。结果与通过钨灯和锁相检测技术获得的结果在10%以内相符。通过比较两种方法的结果，推断出测量的T(e)和n(e)的系统误差小于约10%（对于高达200 eV的T(e)）。还通过与瑞利线强度比较，测量了在Δυ = -587 cm⁻¹（λ = 723.8 nm）、Δν = -354 cm⁻¹（λ = 711.8 nm）和Δν = 354 cm⁻¹（λ = 677.6 nm）处转动拉曼跃迁的绝对截面。未观察到由于可能发生的受激拉曼发射而预期的拉曼能级与热平衡布居的显著偏差。根据测量数据，估计在λ = 694.3 nm处H₂的各向异性极化率为γ = 2.93×10⁻²⁵ cm³±3%。还给出了H₂最强转动谱线的绝对截面。