Ne Emissions from a He Discharge Flow System: I. Relative Transition Probabilities of Ne

Abstract A windowless microwave discharge in He was used to generate Ne emissions in a flow system. Relative transition probabilities for a number of emission arrays were determined from the observed line intensities. Agreement is generally obtained with previous experimental and theoretical work.

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Transition probabilities for lines arising from the 3d4 4p configuration of Cr(II)

Canadian Journal of Physics ◽

10.1139/p94-010 ◽

1994 ◽

Vol 72 (1-2) ◽

pp. 57-60 ◽

Cited By ~ 13

Author(s):

A. M. Gonzalez ◽

M. Ortiz ◽

J. Campos

Keyword(s):

Experimental Data ◽

Emission Line ◽

Sum Rules ◽

Transition Probabilities ◽

Line Strength ◽

Line Intensities ◽

Cr Content ◽

Absolute Scale ◽

Relative Transition ◽

Thin Plasma

Relative transition probabilities for 43 lines arising from the 3d4 4p configuration of Cr(II) with cores 3d4 (5D), 3d4 (3P), and 3d4 (3H) were determined from measurements of emission-line intensities in a laser produced plasma. This experiment was carried out with Al–Cr alloys with a Cr content of about 0.1%, in order to have an optically thin plasma. Transition probabilities were placed on an absolute scale by using, where possible, accurate experimental lifetimes from the literature and line-strength sum rules. Comparison of the present results with the available theoretical and experimental data are made.

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Excitation of the 3s3p62S and 3s23p44s2P Levels of Ar+ and the 736 Å Line of Ne by Electrons

Canadian Journal of Physics ◽

10.1139/p74-108 ◽

1974 ◽

Vol 52 (9) ◽

pp. 786-794 ◽

Cited By ~ 18

Author(s):

K-H. Tan ◽

F. G. Donaldson ◽

J. W. McConkey

Keyword(s):

Excitation Function ◽

Line Intensity ◽

Transition Probabilities ◽

Normalization Procedure ◽

Excitation Process ◽

Line Intensities ◽

Intensity Measurements ◽

Careful Measurement ◽

Relative Transition ◽

Good Agreement

Polarization free measurements are presented of the excitation of the 3s3p62S and 3s23p44s2P levels of Ar+ by electron impact. Line intensity measurements yielded relative transition probabilities in good agreement with the recent calculations of Luyken. A double peaked structure is demonstrated to be a common feature of the excitation functions and reasons for this are discussed. Cascade is shown to be an important excitation process for the 4s levels. Comparison is made with other work where available. As a means of calibration of some of the Ar line intensities, a careful measurement was made of the 736 Å Ne excitation function using the Bethe normalization procedure and the known optical oscillator strength.

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EELS white line intensities calculated for the 3d and 4d metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153919 ◽

1989 ◽

Vol 47 ◽

pp. 388-389

Author(s):

C. C. Ahn ◽

D. H. Pearson ◽

P. Rez ◽

B. Fultz

Keyword(s):

Experimental Data ◽

Line Intensity ◽

Transition Probabilities ◽

Initial Increase ◽

White Line ◽

Hartree Fock ◽

Line Intensities ◽

Integrated Intensity ◽

X Ray Absorption ◽

The Continuum

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.

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