The report describes research applied toward the determination of the feasibility of developing a recombining, electron beam-excited plasma into a pulsed laser of exceptionally high peak power.
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *GAS LASERS, AFTERGLOWS, FEASIBILITY STUDIES,...
Because of the high standards imposed by the Organizing and Program Committees upon the acceptance of papers, this conference provided an optimal format for the dissemination of results in laser science among workers in the field, many of whom are Army Contractors. A compact and profound perception was presented of the state of the art which lies at the nucleus of many applications that are also on interest to the Army. Moreover, participation enable Contractors to obtain a professional...
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS, *SYMPOSIA, *LASER APPLICATIONS, ARMY RESEARCH,...
The report describes research applied toward the determination of the feasibility of developing a recombining, electron beam-excited plasma into a pulsed laser of exceptionally high peak power. The indication of small signal gain for optical amplification at 5875 A is the principal subject of this supplement.
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *GAS LASERS, ELECTRON IRRADIATION, EXCITATION,...
In this work, Several photoconductively- switched stacked Blumlein prototype were developed and successfully tested at power levels approaching 100 MW. These devices had a compact geometry and commutated by a single avalanche photoconductive switch. Special attention was placed on broadening of the switch current channels. Device longevity was tested by fabricating switch with metal or diamond coatings and by implementing different switch/electrode configurations. A significant improvement in...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
The characterization and thermal scaling of the nitrogen ion laser pumped by charge transfer from He2(+) is reported in this work. Intense laser emission in the violet at 427 nm has been observed and found to have a linewidth less than 0.3A. The pumping ion, He2(+), was produced by discharge of a fast- pulsed electron beam gun, APEX-1, into several atmospheres of a mixture of helium and nitrogen. Excitation current densities ranged from 1.1 to 2.5 KA/sq cm at 1 MV over a 1 x 10 cm transverse...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *NITROGEN LASERS, CHARGE TRANSFER,...
The report describes research applied toward the determination of the feasibility of developing a recombining, electron beam-excited plasma into a pulsed laser of exceptionally high peak power.
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *GAS LASERS, AFTERGLOWS, ATOMIC ENERGY LEVELS,...
Populations of nuclear spin isomers of 178Hfm2 can be triggered to release their stored energies by the absorption of x-rays having energies in the range 9-13 keV. We have found the basic absorption spectrum for triggering to be approximately 0.16% of the cross section for photoionization of the L-shell electrons surrounding the isomeric nuclei. The maximum effect is induced by X-rays with energies exceeding the threshold for the photoionization of L3 electrons by amounts less than 10 eV....
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
Studies of the 29 possible candidates to use as the working medium of a gamma ray laser have identified the 31-year isomer of Hafnium-178 as the best. This research was aimed at the development of a production cycle for this rare substance. A major success of this work was the discovery in byproduct debris from the synthesis of medical isotopes of a quantity of this material equal to 99% of the world's inventory. Chemical conditioning and recovery of this sample were initiated. Also, an...
Topics: DTIC Archive, Collins, Carl B., GENERAL COHERENT TECHNOLOGY INC RICHARDSON TX, *HAFNIUM, *LASERS,...
The characterization of the nitrogen ion laser pumped by charge transfer from He2(+) is reported in this work. Intense laser emission in the violet at 427 nm has been observed and found to have a linewidth less than 0.3 A. The pumping ion, He2(+), was produced by discharge of a fast-pulsed electron beam gun, APEX-1, into several atmospheres of a mixture of helium and nitrogen. Excitation current densities were 1.4 KA/sq cm at 1 MV over a 1 x 10 cm transverse geometry. Under these conditions,...
Topics: DTIC Archive, Collins, Carl B, Cunningham, Austin J, TEXAS UNIV AT DALLAS RICHARDSON, *CHARGE...
Nuclear spin isomers store electromagnetic energy at densities reaching 1.3 GJ/g for shelf lives approaching centuries. One example, Hf-178 has been shown to release such stored energy when triggered by x-ray flashes at modest power levels. In this work trigger pulses were derived from a familiar x-ray source typically used in dental medicine. Subsequent experiments using tunable x-rays from the synchrotron radiation source, SPring-8 showed that the triggering was initiated by photoionization...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *ELECTROMAGNETIC RADIATION, *NUCLEAR ISOMERS,...
The report describes research applied toward the determination of the feasibility of developing a recombining, electron beam-excited plasma into a pulsed laser of exceptionally high peak power.
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *GAS LASERS, *PLASMAS(PHYSICS), ATOMIC ENERGY...
In this work, efforts were concentrated upon exploration and examinations of the impedance parameter space and output pulse characteristics of the Blumlein devices to facilitate development of reliable pulsers capable of generating intense ultra wideband electric fields. Output pulse characteristics available from our Blumlein pulsers with different number of lines, line impedances and switching devices were examined. The range of pulse characteristics that may be of interest for Bioelectric...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
The objective of the research described in this report is to determine the feasibility of developing a recombining electron beam-excited plasma into a pulsed laser of exceptionally high peak power. Currently accepted theory indicates that this should be possible. An electron beam-excited helium afterglow system, operating routinely at 5 atmospheres and capable of modification to 20, was developed and instrumented so that spectroscopic observation of transient emissions in the visible and near...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS, *GAS LASERS, ATOMIC ENERGY LEVELS, ELECTRON...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules per liter for thousands of years. However, any plan to use such a resource for a gamma-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated fields of physics. Contents: Photoexcitation of...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
The characterization of the nitrogen ion laser pumped by charge transfer from He2(+) is reported in this work. Intense laser emission in the violet at 427 nm has been observed and found to have a linewidth less than 0.3A. The pumping ion, He2(+), was produced by discharge of a fast-pulsed electron beam gun, APEX-1, into 7 atmospheres of a mixture of helium and nitrogen. Excitation current densities were 1.4KA/sq cm at 1 MV over a 1 x 10 cm transverse geometry. Efficiency is discussed.
Topics: DTIC Archive, Collins, Carl B, Cunningham, Austin J, TEXAS UNIV AT DALLAS RICHARDSON, *GAS LASERS,...
Nuclear spin isomers store electromagnetic energy at densities reaching 1.3 GJ/g for shelf lives approaching centuries. The best combination of shelf life and energy storage is found in Hf-178. It has been shown to release its stored energy when triggered by x-ray flashes at modest power levels. In this work trigger pulses were derived from tunable, monochromatic x-rays produced by synchrotron radiation sources. It was proven that the triggering was initiated by photoionization of an electron...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
An Atmospheric Electrical Avalanche (AEA) laser, stabilized by displacement current preionization, has been developed to support the study of the collisional pumping of the N2(+), B yields X, electronic transition by the kinetic step He2(+) + N2 + He yields N2+(B 2 Sigma sub u) + 3He. With proper preionization, the AEA laser has been operated at a PRF of 1 to 30 Hz in an avalanche mode at 100 to 200 A/sq. cm. and E/p of 5 v/cm/torr. At pressures from 1 to 8 atm an essentially uniform, 30 cu....
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules (1012J) per liter for thousands of years. However, any plan to use such a resource for a gamm-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated fields of physics. Since 1978 we have...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
A major effect was found that had defied the constructi on of a completely satisfactory explanation in terms involving only conventional processes of incoherent excitation. It was the generation of radiofrequency sidebands on the hyperfine Moessbauer spectra of Fe57 in ferromagnetic environments. Through the application to a ferromagnetic iron foil of a magnetic field oscillating at radiofrequencies, several new spectral lines were produced in addition to the usual six hyperfine components of...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *NUCLEAR RADIATION, ENVIRONMENTS,...
The characterization and thermal scaling of the nitrogen ion laser pumped by charge transfer from He(3+) is reported in this work. Intense laser emission in the violet at 427 nm has been observed and found to have a linewidth less than 0.3 A. The pumping ions, He(2+) and He(3+), were produced by discharge of a fast-pulsed electron beam gun, APEX-1, into several atmospheres of a mixture of helium and nitrogen. Excitation current densities ranged from 1.1 to 2.5 KA/sq cm at 1 MV over a 1 x 10 cm...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *NITROGEN LASERS, ATOMIC ENERGY...
This report focuses upon a breakthrough recently realized along the more complex direction toward the coherent pumping of a gamma-ray laser. The intent is to mix the quantum properties of long-lived nuclear states with those able to radiate freely. In this way the metastability of an isomeric state could be switched off. The critical experiment is to show that some laboratory level of coherent input power can affect the properties of a nuclear level. Reported here are the details of a series of...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
The characterization and thermal scaling of the nitrogen ion laser pumped by charge transfer from He(3+) is reported in this work. Intense laser emission in the violet at 427 nm has been observed and found to have a linewidth less than 0.3 A. The pumping ion, HE(3+), was produced by discharge of a fast- pulsed electron beam gun, APEX-1, into several atmospheres of a mixture of helium and nitrogen. Excitation current densities ranged from 1.1 to 2.5 sq cm at 1 MV over a 1 x 10 cm transverse...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *NITROGEN LASERS, ATOMIC ENERGY...
This Conference is sponsored each year by the Division of Electron and Atomic Physics of the American Physical Society, and was hosted this year by UTD. One hundred forty-four papers were presented in 19 sessions. Two workshops were held, one devoted to Atomic and Molecular Collisions Processes in Dense Plasmas and the other to Chemical Processes in Planetary Atmospheres.
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *ELECTRONICS, *SYMPOSIA, *REACTION...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wave length radiation. At the nuclear level the storage of energy can approach tera-Joules 10 to the 12th power per liter for thousands of years. This report focuses on an approach to the gamma-ray laser that depends upon incoherent pumping. This nuclear analog of the ruby laser embodies the simplest concept for a gamma-ray laser and it is not...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman upconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable gamma-radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub-Angstrom wavelengths and...
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules (10 to the 12th power J) per liter for thousands of years. However, any plan to use such a resource for a gamma-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated fields of physics. Our...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
Recent approaches to the problem of the gamma ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules per liter for thousands of years. Any plan to use such a resource for a gamma ray laser poses problems requiring the fusion of concepts taken from relatively unrelated fields of physics. An approach has been pursued for the upconversion of longer wavelength...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS AND...
This report continues to focus upon our approach that is the nuclear analog to the ruby laser. It embodies the simplest concepts for a gamma-ray laser and not surprisingly, the greatest rate of achievement in the quest for a subAngstrom laser continues in that direction. For ruby the identification and exploitation of a band width funnel were the critical keys in the development of the first laser. There was a broad absorption band linked through efficient cascading to the narrow laser level....
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman upconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable Gamma-radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub-Angstrom wavelengths and...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
In this work, experiments with the stacked Blumlein prototype pulsers were conducted under different conditions of operation at power levels bypassing 100 MW. Special attention was placed on broadening of the current channels in the avalanche photoconductive switch in order to improve lifetime. The mechanical and semiconductor properties of amorphic diamond were employed to improve the lifetime by coating the switch cathode or anode areas or both. Issues concerning the switch longevity were...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman upconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable gamma-radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub-Angstrom wavelengths and...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
This contract supported a critical phase of an ongoing project having the objective of determining the feasibility and means of realizing a gamma-ray laser. Previous work had served to establish that a gamma-ray laser is feasible if a certain combination of elementary properties can be found in a real nuclear material. Traditional technology could not support the evaluation of these laser-like properties of nuclei and new methodologies had to be developed. Described here are highly significant...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules (10 to the 12tj power J) per liter for thousands of years. However, any plan to use such a resource for a gamma-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated fields of physics.
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
The objective of this work was to determine the feasibility of developing, first the helium nitrogen charge transfer laser, and later the XeF laser into efficient scalable devices excited by preionized discharges for the production of blue-green outputs. The performance and scalability of the N2(+) laser pumped by charge transfer from He2(+) was determined in such a discharge environment. The gain and saturation parameters were measured and a regenerative amplifier capable of operation at 470.9...
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules (10 to the 12th power J) per liter for thousands of years. However, any plan to use such a resource for a gamma-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated fields of physics. Since...
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
Recent approaches to the problem of the gamma ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules per liter for thousands of years. This report focuses upon the nuclear analog of the optical double resonance methods which produced much of the database at the molecular level that was of such essential use in the development of conventional lasers. Applied most...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman unconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable gamma-radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub-Angstrom wavelengths and...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman upconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable gamma-radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub Angstrom wavelengths and...
Topics: DTIC Archive, Collins,Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy can approach tera-Joules per liter for thousands of years. However, any plan to use such a resource for a gamma-ray laser poses problems of a broad interdisciplinary nature requiring the fusion of concepts taken from relatively unrelated field of physics. Our research group has described...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS,...
In this work, experiments with the stacked Blumlein prototype pulsers were conducted under different conditions of operation at power levels bypassing 100 MW. Special attention was placed on broadening of the current channels in the avalanche photoconductive switch in order to improve lifetime. The mechanical and semiconductor properties of amorphic diamond were employed to improve the lifetime by coating the switch cathode or anode areas or both. Issues concerning the switch longevity were...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON, *GALLIUM ARSENIDES,...
Recent approaches to the problem of the gamma-ray laser have focused upon upconversion techniques in which metastable nuclei are pumped with long wavelength radiation. At the nuclear level the storage of energy on approach teraJoules per liter for thousands of years. This report focuses upon the nuclear analog of the optical double resonance method which produced much of the database at the molecular level that was of such essential use in the development of conventional lasers. Applied most...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...
This project concerns the demonstration of the feasibility of the tuning and perhaps even stimulation of nuclear radiation. Theory has indicated that anti-Stokes Raman upconversion of intense but conventional long wavelength sources of radiation produced by scattering from isomeric states of nuclear excitation could lead to significant sources of tunable gamma radiation characterized by the natural Mossbauer widths of the lines. This would result in lines with sub-Angstrom wavelengths and...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTER FOR QUANTUM ELECTRONICS AND...
Contents: Thermal Economy of a Gamma-Ray Laser; Photoexcitation of Nuclear Isomers by (Gamma, Gamma') Reactions; Adaptation of a Fixed Energy Electron Accelerator to Produce Variable Endpoint Bremsstrahlung; Determination of Gateway States in 197Au with a Compton X-Ray Spectrometer; Calibration of Pulsed Bremsstrahlung Spectra with Photonuclear Reactions of 77Se and 79Br; Scaling to High Average Powers of a Flash X-Ray Source Producing Nanosecond Pulses; Frequency Modulation Spectrometer for...
Topics: DTIC Archive, Collins, Carl B, TEXAS UNIV AT DALLAS RICHARDSON CENTERFOR QUANTUM ELECTRONICS,...