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

1994 ◽  
Vol 72 (1-2) ◽  
pp. 57-60 ◽  
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.

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

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.

RELATIVE TRANSITION PROBABILITIES IN NEON

1966 ◽  
Vol 44 (8) ◽  
pp. 1781-1786 ◽  
Author(s):  
J. C. Irwin ◽  
R. A. Nodwell
Keyword(s):  
Emission Line ◽  
Line Intensity ◽  
Transition Probabilities ◽  
Atomic Transition ◽  
Temperature Measurements ◽  
Intensity Measurements ◽  
Relative Transition ◽  
Reversal Temperature

The relative atomic transition probabilities for the transitions between the 2p53p and 2p53s configurations of NeI have been measured by combining reversal temperature measurements with relative emission line intensity measurements. The relative emission intensities were corrected for self-absorption. The results are compared with those obtained by previous workers.

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

1974 ◽  
Vol 52 (9) ◽  
pp. 786-794 ◽  
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.

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

1980 ◽  
Vol 35 (12) ◽  
pp. 1337-1341 ◽  
Author(s):  
H. K. Haak ◽  
C. Zetzsch ◽  
F. Stuhl
Keyword(s):  
Microwave Discharge ◽  
Transition Probabilities ◽  
Flow System ◽  
Theoretical Work ◽  
Discharge Flow ◽  
Line Intensities ◽  
Relative Transition

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.

scholarly journals The WR/LBV system HD 5980: wind-velocity – brightness correlations

2010 ◽  
Vol 6 (S272) ◽  
pp. 511-512
Author(s):  
Gloria Koenigsberger ◽  
Leonid Georgiev ◽  
D. John Hillier ◽  
Nidia Morrell ◽  
Rodolfo Barbá ◽  
...  
Keyword(s):  
Emission Line ◽  
Line Strength ◽  
High State ◽  
Evolutionary Transition ◽  
Luminous Blue Variables ◽  
Bolometric Luminosity ◽  
Line Intensities ◽  
The Past ◽  
Activity State ◽  
State Of Activity

AbstractThe massive eclipsing system HD 5980 in the Small Magellanic Cloud presented sudden ~1–3 mag eruptive events in 1993-1994, the nature of which is still unexplained. We recently showed that these brief eruptions occurred at the beginning of an extended high state of activity which is characterized by large emission-line intensities and that this high state is currently ending (Koenigsberger et al. 2010). Star A, the more massive member of the 19-day binary, is responsible for the spectacular spectral variations observed over the past 3 decades (see Figure 1). It has a He-enriched stellar wind and is over-luminous for its mass, implying an advanced evolutionary state (Koenigsberger et al. 1998). Data obtained over the past 3 decades show that Star A's wind speed slowed down as the system brightened. Also present in these data is a correlated increase in emission-line strength, visual and UV brigthness. The latter suggests that the high activity state in HD 5980 may be attributed to a bolometric luminosity increase, consistent with the results of Drissen et al. (2001). Hence, HD 5980 may be providing the important clues needed for understanding the behavior of other luminous blue variables and for understainding the evolutionary transition between massive O-type stars and Wolf-Rayet stars.

Experimental transition probabilities of the infrared lines 3p–4s of Ne I and 4p–5s of Ar I

1985 ◽  
Vol 63 (11) ◽  
pp. 1389-1392 ◽  
Author(s):  
I. Tanarro ◽  
J. Campos
Keyword(s):  
Experimental Data ◽  
Line Intensity ◽  
Transition Probabilities ◽  
Theoretical Data ◽  
Light Sources ◽  
Intensity Measurements ◽  
Phase Sensitive ◽  
Relative Transition ◽  
Coulomb Approximation ◽  
Experimental Transition

Relative transition probabilities for the infrared lines 3p–4s of Ne I and 4p–5s of Ar I have been determined from emission line-intensity measurements of optically thin light sources. In this experiment a photoconductive cell and a digital phase-sensitive amplifier have been used for light detection. Transition probabilities have been put on an absolute scale by using the Coulomb approximation. The present experimental data are compared with the existing theoretical data for neon and with experimental and theoretical data for argon.

scholarly journals ANALYSIS OF THE $B \to K^*_2(1430), a_2(1320), f_2(1270)$ FORM-FACTORS WITH LIGHT-CONE QCD SUM RULES

2011 ◽  
Vol 26 (37) ◽  
pp. 2761-2782 ◽  
Author(s):  
ZHI-GANG WANG
Keyword(s):  
Experimental Data ◽  
Light Cone ◽  
B Meson ◽  
Sum Rules ◽  
Form Factors ◽  
Distribution Amplitude ◽  
Qcd Sum Rules ◽  
Line Shapes ◽  
The Future

In this paper, we study the [Formula: see text] form-factors with the light-cone QCD sum rules, where the B-meson light-cone distribution amplitudes are used. In calculations, we observe that the line-shapes of the B-meson light-cone distribution amplitude ϕ+(ω) have significant impacts on the values of the form-factors, and expect to obtain severe constraints on the parameters of the B-meson light-cone distribution amplitudes from the experimental data in the future.

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