scholarly journals MODES OF TRANSILLUMINATION OF THE DENSE PLASMA LAYER VIA ELECTROMAGNETIC BEAM

2021 ◽  
pp. 3-5
Author(s):  
B.R. Mykhailenko ◽  
I.O. Anisimov
Keyword(s):  
Laboratory Experiments ◽  
Dense Plasma ◽  
Plasma Layer ◽  
Incident Beam ◽  
Beam Power ◽  
Channel Formation ◽  
Information Transparency ◽  
Third Harmonic ◽  
Characteristic Modes ◽  
3D Geometry

Interaction of the powerful electromagnetic ray of the limited radius with a dense plasma layer was studied viacomputer simulation using the PIConGPU software package in 3D geometry. The characteristic modes of channel formation in the barrier (namely laminar and turbulent) are described. Turbulent mode can be associated with the fast transillumination, observed in laboratory experiments. The channel formation time as a function of the incident beam power and the plasma layer density is studied. Information transparency is also observed at the third harmonic of the incident wave.

scholarly journals Solid Target System with In-Situ Target Dissolution

Instruments ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 14 ◽  
Author(s):  
William Z. Gelbart ◽  
Richard R. Johnson
Keyword(s):  
Target Material ◽  
Incident Beam ◽  
Chemistry Laboratory ◽  
Target System ◽  
Beam Power ◽  
New Approach ◽  
Target Station ◽  
Production Target ◽  
Design Construction

A significant number of medical radioisotopes use solid, often metallic, parent materials.These materials are deposited on a substrate to facilitate the cooling and handling of the targetduring placing, irradiation, and processing. The processing requires the transfer of the target to aprocessing area outside the irradiation area. In this new approach the target is processed at theirradiation site for liquid only transport of the irradiated target material to the processing area. Thedesign features common to higher energy production target systems are included in the targetstation. The target is inclined at 14 degrees to the beam direction. The system has been designed toaccept an incident beam of 15 to 16 mm diameter and a beam power between 2 and 5 kW. Thermalmodeling is presented for targets of metals and compounds. A cassette of five or 10 preparedtargets is housed at the target station as well as a target dissolution assembly. Only the dissolvedtarget material is transported to the chemistry laboratory so that the design does not requireadditional irradiation area penetrations. This work presents the design, construction, and modelingdetails of the assembly. A full performance characterization will be reported after the unit is movedto a cyclotron facility for beam related measurements.

Characterization of X-ray gas attenuator plasmas by optical emission and tunable laser absorption spectroscopies

2017 ◽  
Vol 24 (6) ◽  
pp. 1195-1208 ◽  
Author(s):  
Álvaro Martín Ortega ◽  
Ana Lacoste ◽  
Stéphane Béchu ◽  
Alexandre Bès ◽  
Nader Sadeghi
Keyword(s):  
Incident Beam ◽  
Tunable Laser ◽  
Optical Emission ◽  
High Energy ◽  
Beam Power ◽  
Beam Path ◽  
Optical Elements ◽  
X Ray ◽  
Laser Absorption ◽  
X Ray Absorption

X-ray gas attenuators are used in high-energy synchrotron beamlines as high-pass filters to reduce the incident power on downstream optical elements. The absorption of the X-ray beam ionizes and heats up the gas, creating plasma around the beam path and hence temperature and density gradients between the center and the walls of the attenuator vessel. The objective of this work is to demonstrate experimentally the generation of plasma by the X-ray beam and to investigate its spatial distribution by measuring some of its parameters, simultaneously with the X-ray power absorption. The gases used in this study were argon and krypton between 13 and 530 mbar. The distribution of the 2pexcited states of both gases was measured using optical emission spectroscopy, and the density of argon metastable atoms in the 1s5state was deduced using tunable laser absorption spectroscopy. The amount of power absorbed was measured using calorimetry and X-ray transmission. The results showed a plasma confined around the X-ray beam path, its size determined mainly by the spatial dimensions of the X-ray beam and not by the absorbed power or the gas pressure. In addition, the X-ray absorption showed a hot central region at a temperature varying between 400 and 1100 K, depending on the incident beam power and on the gas used. The results show that the plasma generated by the X-ray beam plays an essential role in the X-ray absorption. Therefore, plasma processes must be taken into account in the design and modeling of gas attenuators.

Calculation of the source function for an optically dense plasma layer

1968 ◽  
Vol 8 (6) ◽  
pp. 43-47 ◽  
Author(s):  
N. G. Preobrazhenskii ◽  
A. V. Senina ◽  
S. V. Senina
Keyword(s):  
Source Function ◽  
Dense Plasma ◽  
Plasma Layer

Interaction of superstrong electromagnetic pulse with dense plasma layer

2001 ◽  
Author(s):  
Vladimir A. Cherepenin ◽  
Anton S. Il'in ◽  
Victor V. Kulagin
Keyword(s):  
Electromagnetic Pulse ◽  
Dense Plasma ◽  
Plasma Layer

scholarly journals A bükkaljai vízfolyások kanyarulatfejlettségének vizsgálata szerkezetföldtani okok és következtetések

2020 ◽  
Vol 144 (2) ◽  
pp. 133-152
Keyword(s):  
Climate Change ◽  
Morphological Change ◽  
Laboratory Experiments ◽  
Channel Width ◽  
Channel Formation ◽  
Fault Activity ◽  
Channel Depth ◽  
River Terraces ◽  
Form Alone ◽  
Width Change

Rivers react relatively quickly to epirogenetic movements. This is also confirmed through laboratory experiments (Ouchi, S. 1985; Marple, R. T. – Talwani, P. 1993; Twidale, P. 1996, 2004). Many river-related surface-forming processes and forms are used for studying fault activity, for example: channel formation, channel braided, variation of channel width, change of channel depth and river terraces (etc.). However, these processes and forms can be caused by climate change, so the form alone does not prove the structural activity of the area (Schumm , S. A. 1986, 2005; Pinter, N. C. 1996; Petrovszki J. 2013). Such morphological change is the development of river sinuosity, which is often used to justify the activity of faults. Several Hungarian and foreign researchers have been investigating this phenomenon, but have mainly examinied larger rivers. The purpose of this work is to examine the sinuosity of the Bükkalja creeks. I tested and refined the procedure associated with scaling in order to explain the possible causes of changes in the sinuosity of the creeks.

scholarly journals Selected Organometallic Compounds for Third Order Nonlinear Optical Application

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 254 ◽  
Author(s):  
Anna Popczyk ◽  
Aouatif Aamoum ◽  
Anna Migalska-Zalas ◽  
Przemyslaw Płóciennik ◽  
Anna Zawadzka ◽  
...  
Keyword(s):  
Physical Vapor Deposition ◽  
Incident Beam ◽  
Organometallic Compounds ◽  
Basis Set ◽  
Nonlinear Susceptibility ◽  
Third Order ◽  
Linear Absorption ◽  
Third Harmonic ◽  
The Third ◽  
Linear Optical Properties

In this paper, we present the third harmonic generation response of Znq2 (Bis-(8-hydroxyquinolinato)zinc), Cuq2 (8-Hydroxyquinoline copper(II)), and Alq3 (Tris-(8-hydroxyquinoline)aluminum) organometallic compounds. An experiment was conducted for s and p polarizations of incident beam, using the Maker fringes technique. The third order nonlinear susceptibility χ(3) was estimated using the Kubodera and Kobayashi comparative model, on the grounds that presented compounds exhibit high linear absorption of the generated third harmonic wavelength (355 nm). These complexes were deposited as thin films using the physical vapor deposition (PVD) method. Investigated complexes vary in terms of the coordination center and number of quinoline ligands, which visibly influence their nonlinear response. The global hybrid B3LYP functional with the basis set 6-31G(d) was used in computing the linear and non-linear optical properties. The computed γtot value (8765.36 × 10−36 esu for Cuq2) is superior to that of methylene blue (γ = 32.00 × 10−36 esu). The calculated theoretical values were found to be in good agreement with the experimental results.

Laser Induced Solid-State Grain Growth in Polysilicon Films

1989 ◽  
Vol 157 ◽  
Author(s):  
S.A. Ajuria
Keyword(s):  
Thermal Model ◽  
Direct Relationship ◽  
Continuous Wave ◽  
Incident Beam ◽  
Beam Power ◽  
Continuous Wave Laser ◽  
Steady State Temperature ◽  
Long Time ◽  
Polysilicon Films ◽  
Wave Laser

ABSTRACTWe report studies done on the heating of polysillcon thin films below the melting temperature with long-time (on the order of minutes) continuous-wave laser irradiations. It is shown that a well controlled steady-state temperature is locally established within the film. A thermal model is developed to correlate film temperature to beam intensity and a direct relationship is found. A correlation coefficient of 2.5 K/W/cm2 is empirically determined between film temperature and incident beam power density.

Generation and radiation of third harmonics by s-polarized electromagnetic waves incident on a narrow inhomogeneous magnetoactive plasma layer

1989 ◽  
Vol 41 (1) ◽  
pp. 31-36 ◽  
Author(s):  
A. M. Hussein
Keyword(s):  
Electromagnetic Waves ◽  
Plasma Layer ◽  
Magnetoactive Plasma ◽  
Wave Generation ◽  
Inhomogeneous Layer ◽  
Harmonic Waves ◽  
Third Harmonic ◽  
Unmagnetized Plasma ◽  
Incident Waves ◽  
Inhomogeneous Magnetoactive Plasma

An investigation is made of wave generation and radiation of third harmonics by s-polarized electromagnetic waves incident on a narrow inhomogeneous layer of a magnetoactive plasma. The amplitudes of the radiated third-harmonic waves are calculated. In contrast with second harmonics, third harmonics are radiated for the case of normally incident waves on an unmagnetized plasma.

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