The even-parity autoionizing resonance series 5p^5np＇ [3/2]1, [1/2]1, and 5p^5nf＇ [5/2]3 of xenon have been investigated, excited from the two metastable states 5p^56s [3/2]2 and 5p^56s＇ [1/2]0 in the photon energy...The even-parity autoionizing resonance series 5p^5np＇ [3/2]1, [1/2]1, and 5p^5nf＇ [5/2]3 of xenon have been investigated, excited from the two metastable states 5p^56s [3/2]2 and 5p^56s＇ [1/2]0 in the photon energy range of 28000-42000 cm^-1 with experimental bandwidth of -0.1 cm^-1. The excitation spectra of the even-parity autoionizing resonance series show typical asymmetric line shapes. New level energies, quantum defects, line profile indices and resonance widths, resonance lifetimes and reduced widths of the autoionizing resonances are derived by a Fano-type line-shape analysis. The line profile index and the resonance width are shown to be approximately proportional to the effective principal quantum number. The line separation of the 5p^5np＇ autoionizing resonances is discussed.展开更多
The even-parity autoionizing resonance series 3p^5np′[3/2]1,2, 3p^5np′[1/2] 1, and 3p^5nf′[5/2]3 of Ar have been investigated exciting from the two metastable states 3p^54s[3/2]2 and 3p^54s′[1/2]0 in the photon en...The even-parity autoionizing resonance series 3p^5np′[3/2]1,2, 3p^5np′[1/2] 1, and 3p^5nf′[5/2]3 of Ar have been investigated exciting from the two metastable states 3p^54s[3/2]2 and 3p^54s′[1/2]0 in the photon energy range of 32500-35600 cm^-1 with an experimental band- width of ～0.1 cm^-1. The excitation spectra of the even-parity autoionizing resonance series show typical asymmetric line shapes. New level energies, quantum defects, line profile index and resonance widths, resonance lifetime and reduced widths of the autoionizing resonances are derived by a Fano-type line-shape analysis. The line profile index q and the resonance widths F are shown to be approximately proportional to the effective principal quantum number n^＊. The line separation of the 3p^5np′ autoionizing resonances is discussed.展开更多
Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced fro...Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced from photoionization of the neutral atoms are monitored by a home-built time-of-flight mass spectrometer. Photoionization cross sections of the excited states of Ti I were deduced from the dependence of the ion signal intensity on the laser intensity for photon energies close to the ionization threshold. The values obtained range from 0.2 Mb to 6.0 Mb. No significant isotope-dependence was found from measurements of the photoionization cross sections of ^46Ti, ^47Ti, and ^48Ti.展开更多
Quantum molecular dynamic (QMD) simulations have been applied to study the thermophysical properties of liquid xenon under dynamic compressions. The equation of state (EOS) obtained from QMD calculations are corrected...Quantum molecular dynamic (QMD) simulations have been applied to study the thermophysical properties of liquid xenon under dynamic compressions. The equation of state (EOS) obtained from QMD calculations are corrected according to Saha equation, and contributions from atomic ionization, which are of predominance in determining the EOS at high temperature and pressure, are considered. For the pressures below 160 GPa, the necessity in accounting for the atomic ionization has been demonstrated by the Hugoniot curve, which shows excellent agreement with previous experimental measurements, and three levels of ionization have been proved to be sufficient at this stage.展开更多
文摘The even-parity autoionizing resonance series 5p^5np＇ [3/2]1, [1/2]1, and 5p^5nf＇ [5/2]3 of xenon have been investigated, excited from the two metastable states 5p^56s [3/2]2 and 5p^56s＇ [1/2]0 in the photon energy range of 28000-42000 cm^-1 with experimental bandwidth of -0.1 cm^-1. The excitation spectra of the even-parity autoionizing resonance series show typical asymmetric line shapes. New level energies, quantum defects, line profile indices and resonance widths, resonance lifetimes and reduced widths of the autoionizing resonances are derived by a Fano-type line-shape analysis. The line profile index and the resonance width are shown to be approximately proportional to the effective principal quantum number. The line separation of the 5p^5np＇ autoionizing resonances is discussed.
文摘The even-parity autoionizing resonance series 3p^5np′[3/2]1,2, 3p^5np′[1/2] 1, and 3p^5nf′[5/2]3 of Ar have been investigated exciting from the two metastable states 3p^54s[3/2]2 and 3p^54s′[1/2]0 in the photon energy range of 32500-35600 cm^-1 with an experimental band- width of ～0.1 cm^-1. The excitation spectra of the even-parity autoionizing resonance series show typical asymmetric line shapes. New level energies, quantum defects, line profile index and resonance widths, resonance lifetime and reduced widths of the autoionizing resonances are derived by a Fano-type line-shape analysis. The line profile index q and the resonance widths F are shown to be approximately proportional to the effective principal quantum number n^＊. The line separation of the 3p^5np′ autoionizing resonances is discussed.
基金V. ACKNOWLEDGMENTS This work is supported by the National Natural Science Foundation of China （No.10674002 and No.20973001） and the Science Foundation of Anhui Education Committee （No.ZD2007001-1）.
文摘Resonance-enhanced multiphoton ionization of the titanium atoms has been investigated in the 293 321 nm wavelength. We couple a laser-ablated metal target into a molecular beam to produce free atoms. Ions produced from photoionization of the neutral atoms are monitored by a home-built time-of-flight mass spectrometer. Photoionization cross sections of the excited states of Ti I were deduced from the dependence of the ion signal intensity on the laser intensity for photon energies close to the ionization threshold. The values obtained range from 0.2 Mb to 6.0 Mb. No significant isotope-dependence was found from measurements of the photoionization cross sections of ^46Ti, ^47Ti, and ^48Ti.
基金Supported by the Foundation for Development of Science and Technology of China Academy of Engineering Physics under Grant No.2009B0301037
文摘Quantum molecular dynamic (QMD) simulations have been applied to study the thermophysical properties of liquid xenon under dynamic compressions. The equation of state (EOS) obtained from QMD calculations are corrected according to Saha equation, and contributions from atomic ionization, which are of predominance in determining the EOS at high temperature and pressure, are considered. For the pressures below 160 GPa, the necessity in accounting for the atomic ionization has been demonstrated by the Hugoniot curve, which shows excellent agreement with previous experimental measurements, and three levels of ionization have been proved to be sufficient at this stage.
