Инверсия вклада изотопа малой относительной концентрации в суммарный коэффициент поглощения смеси изотопов неона на переходе 3s-=SUB=-2-=/SUB=--2p-=SUB=-4-=/SUB=-

AbstractAbsorption of probe laser radiation by a mixture of even isotopes of neon in a gas discharge plasma is investigated by the method of magnetic scanning of 3 s _2–2 p _4 transition. The contours of absorption lines of isotopes are resolved by means of numerical modeling. It is discovered that, upon decrease in relative concentration of one of the isotopes, its contribution to absorption is replaced by gain. The effect is found to be caused by radiative transfer of excitation energy between atoms of different kinds in the absence of a difference in level energies (the process known as optical pumping). The effect of this mechanism turned out to be substantial for the upper level transitions from which to the ground state are allowed while being absent for the lower level of the transition from which such transitions are forbidden although other decay channels are available.

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New Data from Laser Interrogation of Electron-Atom Collisions Experiments

Australian Journal of Physics ◽

10.1071/ph960499 ◽

1996 ◽

Vol 49 (2) ◽

pp. 499

Author(s):

AT Masters ◽

RT Sang ◽

WR MacGillivray ◽

MC Standage

Keyword(s):

Laser Radiation ◽

Optical Pumping ◽

Single Mode ◽

Ground Level ◽

Stokes Parameters ◽

Scattered Electron ◽

Electron Atom ◽

Level Data ◽

Superelastic Scattering ◽

Upper Level

Recent data from two methods in which high resolution laser radiation is used to assist in determining electron-atom collision parameters are presented. The electron superelastic method has yielded the first measurement of Stokes parameters for electron de-excitation of the 32D5/2–32P3/2,1/2 transition of atomic Na, the upper level having been optically prepared by resonant, stepwise excitation from the 32S1/2 ground level via the 32P3/2 level using two single mode lasers. As well, we report on the development of a model to determine the optical pumping parameters for superelastic scattering from the 32P3/2 level when it is prepared by two lasers exciting from the F = 1 and F = 2 states respectively of the 32S1/ 2 ground level. Data are also presented for collision parameters for the excitation of the 61So–61 PI transition of the I = 0 isotope of Hg by electrons of 50 eV incident energy. The technique employed for these measurements is the stepwise electron–laser excitation coincidence method, in which the electron excited atom is further excited by resonant laser radiation, and fluorescence photons emitted by relaxation from the laser excited state are detected in coincidence with the scattered electron.

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Transport properties of ground-state aluminium atoms in hollow cathode gas discharge plasma

Journal of Physics Conference Series ◽

10.1088/1742-6596/63/1/012008 ◽

2007 ◽

Vol 63 ◽

pp. 012008 ◽

Cited By ~ 1

Author(s):

I M Rusinov ◽

I Bozhinova ◽

A B Blagoev

Keyword(s):

Transport Properties ◽

Hollow Cathode ◽

Ground State ◽

Discharge Plasma ◽

Gas Discharge ◽

Gas Discharge Plasma

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Dynamics of Active Brownian Particles in Plasma

Molecules ◽

10.3390/molecules26030561 ◽

2021 ◽

Vol 26 (3) ◽

pp. 561

Author(s):

Kyaw Arkar ◽

Mikhail M. Vasiliev ◽

Oleg F. Petrov ◽

Evgenii A. Kononov ◽

Fedor M. Trukhachev

Keyword(s):

Experimental Data ◽

Laser Radiation ◽

Discharge Plasma ◽

Surrounding Medium ◽

Dust Particles ◽

Single Particles ◽

Thermophoretic Force ◽

Gas Discharge Plasma ◽

Brownian Particles ◽

Radio Frequency Discharge

Experimental data on the active Brownian motion of single particles in the RF (radio-frequency) discharge plasma under the influence of thermophoretic force, induced by laser radiation, depending on the material and type of surface of the particle, are presented. Unlike passive Brownian particles, active Brownian particles, also known as micro-swimmers, move directionally. It was shown that different dust particles in gas discharge plasma can convert the energy of a surrounding medium (laser radiation) into the kinetic energy of motion. The movement of the active particle is a superposition of chaotic motion and self-propulsion.

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