scholarly journals Возбуждение молекул валина электронным ударом в газовой фазе

2021 ◽  
Vol 47 (14) ◽  
pp. 30
Author(s):  
О.Б. Шпеник ◽  
А.И. Булгакова ◽  
А.Н. Завилопуло ◽  
Н.М. Эрдевди ◽  
Ю.А. Бандурин
Keyword(s):  
Energy Range ◽  
Gas Phase ◽  
Optical Spectroscopy ◽  
Emission Spectra ◽  
Measurement Procedure ◽  
Spectral Lines ◽  
Optical Functions ◽  
Slow Electrons

The measurement procedure and the results obtained by optical spectroscopy upon excitation of valine molecules in the gas phase by slow electrons are described. The emission spectra of the molecules under study in the range of 200-520 nm with excitation by electrons in the energy range of 0-90 eV, as well as the optical functions of the excitation of the most intense spectral lines (bands) of radiation are presented.

Measurement of the spatial characteristics of an erosive silicon laser plasma using small-sized high-resolution spectrometers

2021 ◽  
pp. 38-42
Author(s):  
Boris A. Lapshinov ◽  
Nikolay I. Timchenko
Keyword(s):  
Laser Plasma ◽  
Emission Spectra ◽  
Target Surface ◽  
Spectral Lines ◽  
Slit Diaphragm ◽  
Plasma Radiation ◽  
Atmospheric Conditions ◽  
Spatial Characteristics ◽  
Silicon Target ◽  
Oriented Parallel

The spatial characteristics of the erosion laser plasma are investigated. The application of small-sized spectrometers of the visible and ultraviolet ranges for recording the spectrum of plasma radiation is considered. Erosive laser plasma is formed on the surface of a silicon target under the action of pulsed laser radiation with a wavelength of 1064 nm under normal atmospheric conditions. The laser plasma torch was scanned using a movable slit diaphragm oriented parallel to the target surface. The emission of erosion laser plasma was recorded using small-size spectrometers. Based on the obtained plasma emission spectra, the dependences of the intensity of the spectral lines of silicon on the geometric position of the slit diaphragm are revealed. A comparison is made of the intensities of the spectral lines of silicon on the polished and grinded sides of the target.

Laser excitation and emission spectra of the hexafluorobenzene cation in the gas phase

1981 ◽  
Vol 103 (2) ◽  
pp. 326-329 ◽  
Author(s):  
Trevor Sears ◽  
Terry A. Miller ◽  
V. E. Bondybey
Keyword(s):  
Gas Phase ◽  
Laser Excitation ◽  
Emission Spectra

Study of Temperature Behavior of Luminescence Emission of LaVO4 and La1-xEuxVO4 Powders

2015 ◽  
Vol 230 ◽  
pp. 153-159 ◽  
Author(s):  
Oksana Chukova ◽  
Sergiy G. Nedilko ◽  
Sergiy A. Nedilko ◽  
Tetiana Voitenko ◽  
Olga Gomenyuk ◽  
...  
Keyword(s):  
Emission Spectra ◽  
Spectral Lines ◽  
Temperature Behavior ◽  
Precipitation Method ◽  
Temperature Range ◽  
Luminescence Emission ◽  
Electron Transitions ◽  
The Matrix ◽  
Co Precipitation ◽  
The Eu

The La1‑xEuxVO4 powders were synthesized by co-precipitation method. Emission spectra of the LaEuVO4 and La1‑xEuxVO4 powders consist of wide non-structural bands of the matrix emission and narrow spectral lines caused by inner f-f electron transitions in the Eu3+ ions, respectively. The both types of emission were studied within 8 – 300 K temperature range. Decomposition of spectra of the wide matrix emission on three bands has been carried out and temperature dependencies for each band were studied. Temperature behavior of the Eu3+ emission was investigated for lines assigned to different Eu3+ centres. Obtained dependencies are analyzed and discussed using proposed schemes of transitions in the VO43- groups and structure of the nearest surrounding of the Eu3+ emission centres.

scholarly journals Процессы передачи энергии в эвлитите Sr-=SUB=-3-=/SUB=-Y(PO-=SUB=-4-=/SUB=-)-=SUB=-3-=/SUB=-, по отдельности и одновременно легированном ионами Tb-=SUP=-3+-=/SUP=- и Tm-=SUP=-3+-=/SUP=-

2022 ◽  
Vol 130 (1) ◽  
pp. 99
Author(s):  
Xiaowu Hu ◽  
Fabio Piccinelli ◽  
Marco Bettinelli
Keyword(s):  
Energy Transfer ◽  
Optical Spectroscopy ◽  
Emission Spectra ◽  
Cross Relaxation ◽  
Transfer Efficiency ◽  
Relaxation Processes ◽  
Donor Concentration ◽  
Acceptor Concentration ◽  
Transfer Processes ◽  
Double Phosphate

In this work the optical spectroscopy and the energy transfer processes involving the Tb3+and Tm3+ ions, have been studied in eulytite double phosphate hosts of the type Sr3Y(PO4)3 doped with various amounts of the two Ln ions. It has been found that several energy transfer and cross-relaxation processes are active in this class of materials, upon excitation in the 5D4 level of Tb, and in the 1G4 one of Tm. In particular, a Tb→Tm transfer of excitation has been found to quench strongly the 5D4 level of Tb. This process occurs with a transfer efficiency increasing from 0.08 to 0.62, for a donor concentration of 2 mol%, and an acceptor concentration increasing from 2 to 15 mol%. The emission spectra are strongly affected by the presence of Tb⟷Tm energy transfer, and Tm→Tm cross relaxation processes.

scholarly journals Plasma characteristics of Ag:Al alloy produced by fundamental and second harmonic frequencies of Nd:YAG laser

2019 ◽  
Vol 14 (31) ◽  
pp. 205-214
Author(s):  
Ali A-K. Hussain
Keyword(s):  
Laser Ablation ◽  
Energy Range ◽  
Electron Temperature ◽  
Nd:Yag Laser ◽  
Laser Energy ◽  
Second Harmonic ◽  
Spectral Lines ◽  
Distilled Water ◽  
Harmonic Frequency ◽  
Plasma Characteristics

In this work, the spectra for plasma glow produced by pulseNd:YAG laser (λ=532 and 1064nm) on Ag:Al alloy with same molarratio samples in distilled water were analyzed by studying the atomiclines compared with aluminum and silver strong standard lines. Theeffect of laser energies of the range 300 to 800 mJ on spectral lines,produced by laser ablation, were investigated using opticalspectroscopy. The electron temperature was found to be increasedfrom 1.698 to 1.899 eV, while the electron density decreased from2.247×1015 to 5.08×1014 cm-3 with increasing laser energy from 300to 800 mJ with wavelength of 1064 nm. The values of electrontemperature using second harmonic frequency are greater than of1064 nm, which increased from 2.405 to 2.444 eV, while the electrondensity decreased from 2.210×1015 to 1.516×1015 cm-3 withincreasing laser energy for the same energy range.

scholarly journals Photo-ionized neon plasmas induced by radiation pulses of a laser-plasma EUV source and a free electron laser FLASH

2013 ◽  
Vol 31 (2) ◽  
pp. 195-201 ◽  
Author(s):  
A. Bartnik ◽  
R. Fedosejevs ◽  
P. Wachulak ◽  
H. Fiedorowicz ◽  
C. Serbanescu ◽  
...  
Keyword(s):  
Free Electron ◽  
Free Electron Laser ◽  
Extreme Ultraviolet ◽  
Spectral Characteristics ◽  
Emission Spectra ◽  
Spectral Lines ◽  
Plasma Radiation ◽  
Beam Radiation ◽  
Radiation Beam ◽  
Ionized Plasmas

AbstractIn this work, a laser-produced plasma extreme ultraviolet source and a free electron laser were used to create Ne photo-ionized plasmas. In both cases, a radiation beam was focused onto a gas stream injected into a vacuum chamber synchronously with the radiation pulse. Extreme ultraviolet radiation from the plasma spanned a wide spectral range with pronounced maximum centered at λ = 11 ± 1 nm while the free electron laser pulses were emitted at a wavelength of 32 nm. The power density of the focused plasma radiation was approximately 2 × 107 W/cm2 and was seven orders of magnitude lower compared with the focused free electron laser beam. Radiation fluences in both experimental conditions were comparable. Despite quite different spectral characteristics and extremely different power densities, emission spectra of both photo-ionized plasmas consist of the same spectral lines within a wavelength range of 20 to 50 nm, however, with different relative intensities of the corresponding lines. The dominating spectral lines originated from singly charged ions (Ne II); however, Ne III lines were also detected. Additionally, computer simulations of the emission spectra, obtained for photo-ionized plasmas, driven by the plasma extreme ultraviolet source, were performed. The corresponding measured and calculated spectra are presented. An electron temperature and ionic composition were estimated. Differences between the experimental spectra, obtained for both irradiation conditions, were analyzed. The differences were attributed mainly to different energies of driving photons.

Photolysis of O2 dispersed in solid neon with far-ultraviolet radiation

2018 ◽  
Vol 20 (11) ◽  
pp. 7730-7738 ◽  
Author(s):  
Sheng-Lung Chou ◽  
Jen-Iu Lo ◽  
Yu-Chain Peng ◽  
Hsiao-Chi Lu ◽  
Bing-Ming Cheng ◽  
...  
Keyword(s):  
Ultraviolet Radiation ◽  
Emission Spectra ◽  
Spectral Lines ◽  
Absorption And Emission ◽  
Absorption And Emission Spectra ◽  
Far Ultraviolet

Irradiation of O2 dispersed in solid Ne near 4 K at 173 or 143 nm produced many new spectral lines of O, O2 and O3 in absorption and emission spectra.

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