1. |
- Veenhuizen, Hans, et al.
(author)
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Acquisition and processing of angle-resolved photoelectron spectra excited with focussed polarized resonance radiation
- 1986
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In: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048 .- 1873-2526. ; 41:2, s. 187-203
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Journal article (peer-reviewed)abstract
- A system for the acquisition of angle-resolved photoelectron spectra is described. The sample gas is excited by VUV resonance radiation, which is polarized to about 95% using a fully rotatable fourfold reflection polarizer. One of the mirrors is toroidally shaped in order to focus the radiation into the sample gas cell. This design gives count rates comparable to those obtained by an unpolarized source, and at a greatly reduced background level. A computer controlled system has been developed to automate the recording procedure. It allows for simultaneous recordings of the spectra at the different angular settings, thus eliminating the effects of intensity drifts. Details of calibration procedures and data processing, including spectrum analysis, are given along with a discussion of the accuracy of the results. To illustrate the performance, measured β-values for the main components of the four outermost photoelectron bands in the Hel excited spectrum of CO2 are presented.
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2. |
- Veenhuizen, Hans, et al.
(author)
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High resolution angle-resolved photoelectron spectrum of CO2, excited with polarized resonance radiation
- 1986
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In: Journal of Electron Spectroscopy and Related Phenomena. - : Elsevier BV. - 0368-2048 .- 1873-2526. ; 41:2, s. 205-223
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Journal article (peer-reviewed)abstract
- The He(I) excited and angle-resolved photoelectron spectrum of CO2 is investigated using a focussing VUV-polarizer. High resolution combined with the additional information given by comparing spectra taken at different angles permits detailed analysis of the vibrational structure. β-values are given for all vibrational components hitherto observed in the photoelectron spectrum of the ≈X, ≈A,≈B and ≈C electronic bands. Single excitations of the v3 mode with vibrational energies 181 meV in the estate and 279 meV in the ≈B-state are reported. The peak at 360 meV vibrational energy in the (≈C-state is reinterpreted as a single v3 excitation. The β-values of the most intense peaks are also measured using Ne(I) (16.67 and 16.85 eV), Ne(II) (26.86 and 26.95 eV) and He(II) (40.81) resonance radiations.
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3. |
- Wannberg, Björn, et al.
(author)
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Angular distribution of photoelectrons from p levels in Ar, Kr and Xe close to threshold
- 1986
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In: Journal of Physics B. - : IOP Publishing. - 0953-4075 .- 1361-6455. ; 19:15, s. 2267-2277
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Journal article (peer-reviewed)abstract
- Using a DC discharge VUV source equipped with a rotating, focusing reflection polariser in conjunction with a hemispherical electron spectrometer, the angular distribution of photoelectrons from the outermost p levels in the noble gases Ar, Kr and Xe was measured in the kinetic-energy region 0-3 eV. Discharges in Ne, Ar, Kr, Xe and N2 are used to obtain photons with energies in the range 11-19 eV. For photon energies between the ionisation thresholds for the P3/2 and P1/2 levels, observed rapid oscillations in beta are correlated with resonances with autoionising states. For higher photon energies, the energy dependence of beta is smooth.
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