scholarly journals Оптические переходы в кристаллах ZnSe и CdTe с участием d-зон катионов

2018 ◽  
Vol 52 (3) ◽  
pp. 304
Author(s):  
В.В. Соболев ◽  
Д.А. Перевощиков
Keyword(s):  
Reflectance Spectra ◽  
Oscillator Strengths ◽  
Diagram Technique ◽  
Argand Diagram ◽  
Spectral Parameters ◽  
Integral Relations ◽  
Exciton Transitions

AbstractThe permittivity spectra ε_1( E ) and ε_2( E ) of ZnSe and CdTe crystals are calculated in the range of 10–25 eV using their experimental reflectance spectra and Kramers–Kronig integral relations. The spectra are decomposed into thirteen and twelve separate transition bands for ZnSe and CdTe, respectively, using the improved nonparametric combined Argand diagram technique. The main spectral parameters, including the maximum energies and halfwidths and oscillator strengths, are determined. The oscillator strengths are found to be within 0.1–1.4 for ZnSe and 0.2–0.7 for CdTe. The obtained ε_2( E ) bands are due to interband and exciton transitions with the involvement of cation core d bands of both crystals under consideration.

scholarly journals Оптические переходы с остовных d-уровней арсенида галлия

2018 ◽  
Vol 60 (3) ◽  
pp. 476
Author(s):  
Д.А. Перевощиков ◽  
В.В. Соболев
Keyword(s):  
Gallium Arsenide ◽  
Integral Relation ◽  
Half Width ◽  
Reflectance Spectra ◽  
Oscillator Strengths ◽  
Optical Transitions ◽  
Permittivity Spectrum ◽  
Exciton Transitions

AbstractAn improved parameter-free method of joint Argand diagrams was used to expand the permittivity spectrum of gallium arsenide in a region of 19–26 eV into 12 bands of optical transitions with determining their maximum and half-width energies, as well as the oscillator strengths. The values of oscillator strengths of the obtained bands lie within an interval from 0.0009 to 0.06. In the regions of 19.2–21.3 and 24–26 eV, the permittivity spectrum was preliminarily calculated on the basis of experimental reflectance spectra with the use of the Kramers–Kronig integral relation method. The nature of the obtained transition bands is suggested in terms of the band-to-band and exciton transitions.

scholarly journals Transition spectral parameters of In-like Ba, La and Ce ions

2021 ◽  
Author(s):  
Miao Wu ◽  
Zhencen He
Keyword(s):  
Quantum Electrodynamics ◽  
Transition Probabilities ◽  
Energy Levels ◽  
Oscillator Strengths ◽  
Spectral Parameters ◽  
Hartree Fock ◽  
Experimental Values ◽  
Theoretical Results ◽  
Good Agreement ◽  
Line Strengths

The spectral parameters (energy levels, wavelengths, transition probabilities, line strengths and oscillator strengths) of resonance lines for Ba VIII, La IX and Ce X have been performed using the multiconfiguration Dirac-Hartree-Fock method, the contributions of quantum electrodynamics and Breit interactions correction are taken into considered. The calculated results of energy levels and wavelengths are in good agreement with experimental values and other calculation. The number of energy levels and wavelengths considered is larger than that of any other experiment values and other calculations. The transition probabilities, line strengths and oscillator strengths are also calculated where no other theoretical results and experimental values are available.

Mineralogy of the far-side lunar surface explored by Chang’E-4 with visible and near-infrared reflectance spectra

2021 ◽  
Author(s):  
Gen Ito ◽  
Jessica Flahaut ◽  
Jun Huang
Keyword(s):  
Near Infrared ◽  
Spectral Band ◽  
Reflectance Spectra ◽  
Composition Analysis ◽  
Near Infrared Reflectance ◽  
Spectral Parameters ◽  
Moon Mineralogy Mapper ◽  
Band Depth ◽  
The Relationship ◽  
Initial Classification

<p>The far side of the Moon, which has generally been less frequently targeted by robotic and human missions in the past, has become more available for compositional analyses with measurements made by the Chang’E-4 mission that landed in South Pole-Aitken Basin in 2019. The rover of the mission, Yutu-2, has traversed over 500 m now and acquired more than 100 measurements of visible and near-infrared (VNIR) reflectance spectra. In this study, we analyze the full set of VNIR reflectance spectra collected so far in order to better understand the geology of the Von Karman mare. We compute spectral parameters to quantize major features of spectra and infer mineralogy, e.g., pyroxene composition analysis using the relationship between spectral band depths at 1 µm and 2 µm. Many of Chang’E-4 spectra do not have a detectable spectral band at 2 µm in which case we use spectral parameters for the band at 1 µm to make classifications and infer the presence of other minerals. Pyroxene composition inferred from Chang’E-4 spectra are midway between orthopyroxene and clinopyroxene, showing noticeably unique grouping when compared with 1 µm and 2 µm band depth data available from past studies. For spectra without detectable band at 2 µm, initial classification efforts based solely on spectral parameters of the 1 µm band seem to indicate that at least two distinct groups exist. We are further investigating these preliminary findings, such as through comparisons to data from Moon Mineralogy Mapper, to better understand the mineralogy of the measured materials and the geology of the region explored by Yutu-2 rover. </p>

Oscillator Strength Measurements in the Vacuum-Ultraviolet by the Emission Method

1988 ◽  
Vol 102 ◽  
pp. 353-356
Author(s):  
C. Goldbach ◽  
G. Nollez
Keyword(s):  
Oscillator Strength ◽  
Vacuum Ultraviolet ◽  
Oscillator Strengths ◽  
Emission Method ◽  
Absolute Scale ◽  
Good Agreement

AbstractThe principles and the realization of an experiment devoted to oscillator strength measurements in the vacuum-ultraviolet by the emission method are briefly presented. The results obtained for the strong multiplets of neutral nitrogen and carbon in the 1200-2000 Å range yield an absolute scale of oscillator strengths in good agreement with the most recent calculations.

Semiclassical calculation of oscillator-strengths

1989 ◽  
Vol 50 (1) ◽  
pp. 35-44 ◽  
Author(s):  
R.M. More ◽  
K.H. Warren
Keyword(s):  
Oscillator Strengths

Effect of amiodarone on heart rate variability in patients with newly diagnosed atrial fibrillation (clinical observation)

2020 ◽  
pp. 81-85
Author(s):  
E. P. Popova ◽  
O. T. Bogova ◽  
S. N. Puzin ◽  
D. A. Sychyov ◽  
V. P. Fisenko
Keyword(s):  
Atrial Fibrillation ◽  
Heart Rate ◽  
Heart Rate Variability ◽  
Drug Therapy ◽  
Heart Function ◽  
Newly Diagnosed ◽  
Class Iii ◽  
Spectral Parameters ◽  
Patient Will ◽  
The Individual

Spectral analysis of heart rate variability gives an idea of the role of the autonomic nervous system in the regulation of chronotropic heart function. This method can be used to evaluate the effectiveness of drug therapy. Drug therapy should be carried out taking into account the individual clinical form of atrial fibrillation. Information about the vegetative status of the patient will undoubtedly increase the effectiveness of treatment. In this study, spectral parameters were studied in patients with newly diagnosed atrial fibrillation. The effect of antiarrhythmic drug class III amiodarone on the spectral parameters of heart rate variability was studied.

Study of vegetation red edge indices of reflectance spectra for crops of winter wheat cultivated in the steppe zone of Ukraine

2012 ◽  
Vol 18 (4(77)) ◽  
pp. 45-51
Author(s):  
G.M. Zholobak ◽  
◽  
Z.M. Shportiuk ◽  
O.N. Sibirtseva ◽  
S.S. Dugin ◽  
...  
Keyword(s):  
Winter Wheat ◽  
Steppe Zone ◽  
Reflectance Spectra ◽  
Red Edge
Sign in / Sign up

Export Citation Format

Share Document