Experimental Spectroscopy Investigation Of The Rydberg States And Autoionizing Resonances Of The Rare Gas

The atom spectroscopy on atom high-excited states is of great significance in many fields such as astrophysics,controlled nuclear fusion,electron correlation effects, laser isotope separation,and new laser system developing,and so on.This dissertation presents the experimental study on excitation spectra of rare gas autoionizing resonances.The metastable levels of the rare gases were produced by the pulsed DC discharge under the supersonic free jet condition and investigated by laser excitation spectroscopy and time-of-flight ion detection.This dissertation contains three parts: the autoionizing resonances and Rydberg states spectrum of Ar;the autoionizing resonances and Rydberg states spectrum of Kr;the autoionizing resonances and Rydberg states spectrum of Xe.Metastable Ar^*,Kr^* and Xe^* atoms were produced in their metastable states mp⁵(m+1)s[3/2]₂ and mp⁵(m+1)s'[1/2]₀(m=3,4,5 for Ar,Kr and Xe respectively)by a pulsed DC discharge in a beam,and were subsequently excited to the even-parity autoionizing resonance series mp⁵np'[3/2]_1,2,mp⁵np'[1/2]₁,and mp⁵nf[5/2]₃(m= 3,4,5 for Ar,Kr and Xe respectively)by single photon excitation with a pulsed dye laser.The excitation spectra of the even-parity autoionizing resonance series from the metastable Ar^*,Kr^* and Xe^* were obtained by recording the Ar⁺,Kr⁺ and Xe⁺ ions with MCP detection on time-of-flight in the photon energy range of 28000-40000 cm^-1with an experimental bandwidth of～0.1cm^-1.The main results are summarized as follows:(1)The series levels and quantum defects of rare gases autoionizing resonances are determined:for Ar autoionizing resonances states 3p⁵(²P_1/2)np'[3/2]₂(n=11-39), [3/2]₁(n=11-29),[1/2]₁(n=11-22),3p⁵(²P_1/2)nf'[5/2]₃(n=9-38);for Kr autoionizing resonances states 4p⁵(²P_1/2)np'[3/2]₂(n=8-39),[3/2]₁(n=8-34),[1/2]₁ (n=8-26),4p⁵(²P_1/2)nf[5/2]₃(n=5-34);for Xe autoionizing resonances states 5p⁵(²P_1/2)np'[3/2]₁(n=7-28),[1/2]₁(n=7-37),5p⁵(²P_1/2)nf[5/2]₃(n=4-31). Almost half of the data is reported firstly. (2)Quantum defects,line profile index and resonance widths,resonance lifetime and reduced widths of the autoionizing resonances states were derived by a Fano-type line-shape analysis for all observed levels which most of them were observed first time in current operation.The line profile index q and the resonance widthsΓare shown to be approximately proportional to the effective principal quantum number n^*.(3)The line separation of the mp⁵np'(m=3,4,5 for Ar,Kr and Xe respectively) autoionizing resonances was observed and discussed.(4)The high resolution Stark effect spectroscopy of mp⁵nf'(m=3,4,5 for Ar,Kr and Xe respectively)autoionizing resonances in various electric field strengths were detected,and discussed with degenerate perturbation theory.The experiment results accord with the theory very well.(5)The shifts of the ionization potential in various electric field strengths were discussed at last.