Electric-Pulse-Initiated Chemical Laser PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Electric-Pulse-Initiated Chemical Laser PDF full book. Access full book title Electric-Pulse-Initiated Chemical Laser by R. I. Rudko. Download full books in PDF and EPUB format.
Author: R. I. Rudko
Publisher:
ISBN:
Category :
Languages : en
Pages : 102
Get Book Here
Book Description
This study deals with a high-repetition-rate multispectral laser source providing simultaneous emission on many lines in the 2.5-3.0 micron, 3.5-4.0 micron, and 4.3-5.0 micron regions. This program was an experimental investigation to assess the operational characteristics of compact, high-repetition-rate mid-infrared laser sources capable of multispectral operation. An HF/DF/HBr, electrically-initiated TE chemical laser was originally selected as a good candidate for such a system. HBr was found not to be a suitable laser medium for a small system, owing to its low gain. An HF-laser-pumped, isotopic CO2 laser was selected to replace it and to cover the 4.3-5.0 micron region. This laser was investigated in an extension of the original contract. The HF/DF chemical laser was capable of sustaining up to 10,000 discharges per second in gas mixtures containing SF6 and, separately or jointly, H2 and D2. Over 1 millijoule per pulse outputs were obtained up to 4,200 pps in HF, weaker outputs being still available even at the 10,000 pps repetition rate. Peak average powers were 4.5 W for HF and 2.0 W for DF lasers. The laser was operated in a recirculating mode to make efficient use of the reactant gases. Chemical scrubbers were used to remove the discharge and reaction products, thus improving laser performance. Atmospheric pressure operation of this system was also achieved.
Author: R. I. Rudko
Publisher:
ISBN:
Category :
Languages : en
Pages : 102
Get Book Here
Book Description
This study deals with a high-repetition-rate multispectral laser source providing simultaneous emission on many lines in the 2.5-3.0 micron, 3.5-4.0 micron, and 4.3-5.0 micron regions. This program was an experimental investigation to assess the operational characteristics of compact, high-repetition-rate mid-infrared laser sources capable of multispectral operation. An HF/DF/HBr, electrically-initiated TE chemical laser was originally selected as a good candidate for such a system. HBr was found not to be a suitable laser medium for a small system, owing to its low gain. An HF-laser-pumped, isotopic CO2 laser was selected to replace it and to cover the 4.3-5.0 micron region. This laser was investigated in an extension of the original contract. The HF/DF chemical laser was capable of sustaining up to 10,000 discharges per second in gas mixtures containing SF6 and, separately or jointly, H2 and D2. Over 1 millijoule per pulse outputs were obtained up to 4,200 pps in HF, weaker outputs being still available even at the 10,000 pps repetition rate. Peak average powers were 4.5 W for HF and 2.0 W for DF lasers. The laser was operated in a recirculating mode to make efficient use of the reactant gases. Chemical scrubbers were used to remove the discharge and reaction products, thus improving laser performance. Atmospheric pressure operation of this system was also achieved.
Author: Jerald V. Parker
Publisher:
ISBN:
Category :
Languages : en
Pages : 227
Get Book Here
Book Description
The initiation of pulsed chemical laser action by a transverse electrical discharge was investigated. The laser system under study is H2-F2-HE at pressures up to 1 atmosphere. This report discusses three aspects of the electrically initiated pulsed chemical laser. These are: (1) preionization using spark generated ultraviolet radiation to provide a uniform initiating discharge, (2) parametric measurements of electrical and chemical efficiency of the electrically initiated H2-F2 laser, and (3) modeling of the pulsed H2-F2 laser system and projected performance for large-scale devices. It is the conclusion of this work that the electrically initiated H2-F2 chain reaction laser possesses an electrical efficiency significantly higher than any existing pulsed laser, and that the energy per unit volume is competitive with the best state of the art pulsed CO2 or CO lasers. (Author).
Author: T. V. Jacobson
Publisher:
ISBN:
Category :
Languages : en
Pages : 3
Get Book Here
Book Description
Laser action was observed for the first time in several new chemical systems in which HF was produced following a pulsed electrical discharge. The use of transverse multiple discharges enabled high pulse energies and peak powers to be obtained. It was possible to correlate the energy measurements and the spectroscopic output with the exothermicity of the reaction F + RH = HF + R. (Author).
Author: Ronald F. Paulson
Publisher:
ISBN:
Category :
Languages : en
Pages : 63
Get Book Here
Book Description
The results of a numerical simulation of the electrical discharge initiation by a pin discharge of an SF6:H2 reaction in a pulse HF laser system are given. A parameter variation of the amplitude and the temporal length and shape of the electrical discharge pulse is made. The resulting chemical reactions are simulated by the rate equation method for a reaction in a reaction cell, a laser cavity, and a laser amplifier. The effect of spatial inhomogeneity of the chemical reaction in a laser amplifier is considered. A pin electrical discharge laser system used in the initial experimental studies of the initiation of chemical reactions is described. Typical laser output pulses for the system are shown for SF6:H2:He reactants. (Author).
Author: Jeffrey I. Steinfeld
Publisher: Springer Science & Business Media
ISBN: 1468438638
Category : Technology & Engineering
Languages : en
Pages : 283
Get Book Here
Book Description
The possibility of initiating chemical reactions by high-intensity laser exci tation has captured the imagination of chemists and physicists as well as of industrial scientists and the scientifically informed public in general ever since the laser first became available. Initially, great hopes were held that laser-induced chemistry would revolutionize synthetic chemistry, making possible "bond-specific" or "mode-specific" reactions that were impos sible to achieve under thermal equilibrium conditions. Indeed, some of the early work in this area, typically employing high-power continuous-wave sources, was interpreted in just this way. With further investigation, however, a more conservative picture has emerged, with the laser taking its place as one of a number of available methods for initiation of high-energy chemical transformations. Unlike a number of these methods, such as flash photolysis, shock tubes, and electron-beam radiolysis, the laser is capable of a high degree of spatial and molecular localization of deposited energy, which in turn is reflected in such applications as isotope enrichment or localized surface treatments. The use of lasers to initiate chemical processes has led to the discovery of several distinctly new molecular phenomena, foremost among which is that of multiple-photon excitation and dissociation of polyatomic molecules. This research area has received the greatest attention thus far and forms the focus of the present volume.
Author: S. T. Amimoto
Publisher:
ISBN:
Category :
Languages : en
Pages : 16
Get Book Here
Book Description
The performance of a pulsed HF (DF) chain laser was investigated for the case of transverse initiation by a magnetically confined electron beam. Laser energy and beam quality are presented as functions of electron-gun, magnetic field, gas mixture, and optical resonator parameters; results include 79 s/liter HF laser output and electrical efficiency for conversion of total incident electron-beam energy to laser output energy of 45%. (Author).
Author: S Rafi Ahmad
Publisher: John Wiley & Sons
ISBN: 1118683501
Category : Science
Languages : en
Pages : 302
Get Book Here
Book Description
The book gives an introduction to energetic materials and lasers, properties of such materials and the current methods for initiating energetic materials. The following chapters and sections highlight the properties of lasers, and safety aspects of their application. It covers the properties of in-service energetic materials, and also materials with prospects of being used as insensitive ammunitions in future weapon or missiles systems or as detonators in civilian (mining) applications. Because of the diversity of the topics some sections will naturally separate into different levels of expertise and knowledge.
Author: L. Y. Nelson
Publisher:
ISBN:
Category :
Languages : en
Pages : 65
Get Book Here
Book Description
The report describes the results of two separate experimental investigations. The first concerns the electrical excitation of the HCl chemical laser and was motivated by the potential improvement of the laser performance by the vibrational enhancement of the reaction Cl + H2(v=1) yields HCl(v=v,1) + H. Detailed kinetic modelling of the e-beam and e-beam sustained idscharge experiments was used in the interpretation of the experimental data. The rate constant for the vibrationally enhanced reaction was 40 times larger than for the reaction with H2(v=0) at T = 300K. This enhanced rate is not fast enough to lead to efficient use of the H2(v=1) excited by electron impact. The maximum electrical to laser conversion efficiency obtained was 3 percent. The second part of the report describes measurements of the threshold pumping power density in e-beam sustained discharge excitation of KrF and XeF lasers. Stable discharges were obtained in Ar-Kr-F2 and Ar-Xe-NF3 mixtures at 1 atm for times greater than 0.5 microsecond and lasing pulse width as long as 0.5 microsecond. The threshold pump power densities varied inversely with the cavity build up time. Based on the present results it is evident that efficient laser operation in KrF and XeF could be achieved in a 1-m long sustained discharge with input power densities in the range of 50 to 100 kW/cu cm over a 1 microsecond time scale. (Author).
Author: Victor V. Apollonov
Publisher: CRC Press
ISBN: 1000066215
Category : Technology & Engineering
Languages : en
Pages : 227
Get Book Here
Book Description
This book explores new principles of Self-Initiating Volume Discharge for creating high-energy non-chain HF(DF) lasers, as well as the creation of highly efficient lasers with output energy and radiation power in the spectral region of 2.6–5 μm. Today, sources of high-power lasing in this spectral region are in demand in various fields of science and technology including remote sensing of the atmosphere, medicine, biological imaging, precision machining and other special applications. These applications require efficient laser sources with high pulse energy, pulsed and average power, which makes the development of physical fundamentals of high-power laser creation and laser complexes of crucial importance. High-Energy Ecologically Safe HF/DF Lasers: Physics of Self-Initiated Volume Discharge-Based HF/DF Lasers examines the conditions of formation of SSVD, gas composition and the mode of energy input into the gas on the efficiency and radiation energy of non-chain HF(DF) lasers. Key Features: Shares research results on SSVD in mixtures of non-chain HF(DF) lasers Studies the stability and dynamics of the development of SSVD Discusses the effect of the gas composition and geometry of the discharge gap (DG) on its characteristics Proposes recommendations for gas composition and for the method of obtaining SSVD in non-chain HF(DF) lasers Develops simple and reliable wide-aperture non-chain HF(DF) lasers and investigates their characteristics Investigates the possibilities of expanding the lasing spectrum of non-chain HF(DF) lasers
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 98
Get Book Here
Book Description
It has been proposed that trace addition of ClF3 to conventional gas mixtures in photo-initiated HF/DF pulsed lasers might substantially improve chain reaction initiation and consequently, system electrical efficiency. It has further been proposed that steady flow of a spatially tailored trace addition of ClF3 might improve uniformity of initiation and, hence, cavity homogeneity in reptitively pulsed devices by providing enhanced initiation (F-atom production) in regions of diminished lamp illumination. An argon filled flash lamp with pulse duration (FWHM) of approximately 40 microsec was observed to radiate 3.5% of its initial electrical energy in the absorption band of ClF3 (1750A to 2400A) and 13% of its energy in the absorption band of F2 (2400A to 3400A). Theoretical modeling of flash lamp radiation indicates that short lamp pulses appropriate to pulsed chemical lasers would show equal or better radiation distribution of lamp electrical energy in these absorption bands. The flash lamp was used in photolysis studies which show that absorption of radiation by ClF3 results in dissociation with efficiency of order unity. Photolytic production of F-atoms could not be determined in the present UV attenuation studies due to the occurrence of a strongly absorbing unidentified photolysis product or products.
