Experimental high resolution study of the photoproduction of Ne⁺3p satellites in the threshold energy range

Abstract

Cross sections for photon-induced production of Ne+ in the 2p4(3P)3p 2P, 4P, 2D, 2p4(1D)3s 2D and 2s2p6 2S states have been measured for energies between 52 eV and 55.5 eV. Linearly polarized undulator radiation with a bandwidth of 18 meV and 4.5 meV was used. The applied method of photon-induced fluorescence spectroscopy allows the measurement of the alignment A20 of the excited states with all fine structure components being resolved. Autoionization from doubly excited Rydberg states was observed as a dominating population mechanism, except for the 2p4(3P)3p 2PJ and the 2s2p6 2S1/2 states. These states are also populated directly, showing interference profiles in their cross section energy dependence. The remarkly direct population of the 2p4(3P)3p 2PJ states and the excitation of the 2p4(3P)3p 2P3/2,1/2 ns,nd Rydberg series can qualitatively be related to the 2p53p admixture of the Ne ground state. The measured alignment values allow an analysis of the photoelectron partial waves with respect to the dominating jel values. So far, no theoretical analysis has been carried out for comparison.

Extreme Ultraviolet to Visible Dispersed Single Photon Detection for Highly Sensitive Sensing of Fundamental Processes in Diverse Samples

“…By measuring the Lyman series emission from a neutral hydrogen dissociation fragment, the dissociation cross section into excited hydrogen fragments with different quantum number n was quantified. In addition, the investigation of atomic species can reveal relative or absolute cross sections of state selective photoionization and autoionization processes, as it was demonstrated mostly for noble gas targets (see e.g., [ 28 , 32 , 37 , 38 , 39 ]).…”

Photon-excitation photon-emission maps (PhexPhem maps) with rovibronic resolution as a data base for theory and astrophysics part I: method and first results for H2

“…Photon emission is recorded at 90 • with respect to the polarization axis of the synchrotron radiation by a 1 m NIM spectrometer, alternatingly equipped with two types of position sensitive detection systems (see text). on a set of experimental techniques collectively called photoninduced fluorescence spectroscopy (PIFS) (Schmoranzer et al 1986, Schmoranzer et al 2001, Zimmermann et al 2004, Hans et al 2018 which in several cases has also been used to determine absolute emission cross sections (Ehresmann et al 1994a(Ehresmann et al ,1994b. A sketch of the current set-up is displayed in figure 1.…”

Many-electron dynamics of atomic processes studied by photon-induced fluorescence spectroscopy

“…In this sense, it is necessary to convert the recorded with their detectors, a Wollaston prism for polarization measurements, the target cell (with openings for observation of the interaction area under 90 • , an optical system with photomultiplier and a photodiode for flux monitoring are displayed. Adapted from (Zimmermann et al, 2004).…”

“…An advanced PIFS setup using a Wollaston prism (see Fig. 6) has been applied by Zimmermann et al (2004) to measure the alignment parameters of the odd 2p 4 ( 3 P )3p 4,2 P o 3/2 , 2 D o tures. However, some of the computed features deviated (sometimes up to 0.1 eV) from the measured ones.…”

“…An advanced PIFS setup using a Wollaston prism (see Fig. 6) has been applied by Zimmermann et al (2004) to measure the alignment parameters of the odd 2p 4 ( 3 P )3p states of Ne II in the exciting-photon energy range of 52 eV ≤ ω ≤ 55.5 eV at a resolution of 18 meV. In addition, these authors obtained PICS for the population of the even 2s 1 2p 6 2 S and 2p 4 ( 1 D)3s 2 D states at the high resolution of 4.5 meV.…”