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Doppler shifted Fourier transform emission spectroscopy.

机译：多普勒频移傅里叶变换发射光谱。

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This thesis research is concerned about the Doppler shifts observed in emission spectra as a phenomenon as related to the basic atomic and molecular physics, processes in a discharge plasma and parameters that specify a plasma. The Doppler shifted spectra are obtained using a Fourier transform spectrometer and a polarity-witching DC glow discharge plasma as light source. The carriers of the spectra include a variety of electronically excited ions and neutrals.; For ions, N{dollar}sb2sp+{dollar} and Ar{dollar}sp+{dollar} have been chosen for the study. The observed large difference in Doppler shift for the emissions from B and A states of N{dollar}sb2sp+{dollar} is found to be orignated from the difference in lifetime for the two states. The Doppler shifts for emissions from short-lived B state have been used to determine the electric field of plasmas. The emission lines of Ar{dollar}sp+{dollar} in a He discharge exhibit two distinct Doppler shifts (one an order of magnitude greater than the other) depending on the excitation energies of the emitting states. The analysis of the data has led to the establishing of the mechanisms that produce the excited state Ar{dollar}sp+{dollar} in a Ar/He discharge.; Doppler shifts of emissions from neutral species have been observed for the first time in the positive column of a DC glow discharge. The emissions of H{dollar}sb2{dollar} and its isotopomers have been chosen for a detailed study. Experimental evidence supports the conclusion that the observed shifts derive from momentum transfer during electron-molecule collisions that produce the emissive states. A theoretical model has been formulated to relate Doppler shifts to the drift velocity of electrons in the discharge as well as to the momentum transfer of electron-molecule collisions. Predications based on the model are consistent with the experimental observations.; The effect of radiation trapping on the Doppler shifts neutral emissions is a new and interesting result of this thesis research. It has been found theoretically that when an emitting upper state is involved in radiation trapping, the Doppler shifts of emissions from the state will be reduced by a factor of {dollar}0 < beta < 1{dollar}. For a given geometry of emission source, {dollar}beta{dollar} depends only on the absorption coefficient. This property leads to a simple relation between the densities of two absorbing states that involve in radiation trappings and allows one to determine the density of one state from the other. Experimentally the {dollar}beta{dollar} values for emissions of 2{dollar}sp1{dollar}S-3{dollar}sp1{dollar}P and 2{dollar}sp3{dollar}S-2{dollar}sp3{dollar}P of He have been determined and the absolute density of metastable He(2{dollar}sp3{dollar}S) has been deduced from the measured {dollar}beta{dollar} values and the known density of ground state He atoms.
机译：本文的研究涉及在发射光谱中观察到的多普勒频移，这是一种与基本原子和分子物理学，放电等离子体中的过程以及指定等离子体的参数有关的现象。多普勒频移光谱是使用傅立叶变换光谱仪和具有极性的直流辉光放电等离子体作为光源获得的。光谱的载流子包括各种电子激发的离子和中性离子。对于离子，已选择N {dollar} sb2sp + {dollar}和Ar {dollar} sp + {dollar}进行研究。从两种状态的寿命差异可以看出，观测到的N {dollar} sb2sp + {dollar}的B和A态发射的多普勒频移差异很大。短期B状态发射的多普勒频移已用于确定等离子体的电场。 He放电中的Ar {dollar} sp + {dollar}的发射线根据发射态的激发能表现出两个不同的多普勒频移（一个比另一个大一个数量级）。数据分析导致建立了在Ar / He放电中产生激发态Ar {dol} sp + {dol}的机理。在直流辉光放电的正栏中首次观察到中性物质发射的多普勒频移。选择了H {dolb} sb2 {dollar}及其同位异构体的排放进行详细研究。实验证据支持这样的结论，即观察到的位移源自产生发射态的电子-分子碰撞过程中的动量传递。已经建立了一个理论模型，将多普勒频移与放电中电子的漂移速度以及电子-分子碰撞的动量传递相关联。基于模型的预测与实验观察结果一致。辐射俘获对多普勒频移中性发射的影响是本论文研究的一个新的有趣结果。从理论上已经发现，当在辐射捕获中涉及发射的高位态时，该状态的发射的多普勒频移将减小{0美元} 0

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