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Articles 33361 - 33390 of 36553

Full-Text Articles in Physical Sciences and Mathematics

Harmonic Gauge In Canonical Gravity, K. V. Kuchal, Charles G. Torre Jan 1991

Harmonic Gauge In Canonical Gravity, K. V. Kuchal, Charles G. Torre

All Physics Faculty Publications

The Isham-Kuchař representation theory of the spacetime diffeomorphism group in canonical geometrodynamics is implemented in the context of harmonic coordinate conditions. The representation is carried by either an extended phase space, consisting of the cotangent bundle over the space of three-metrics, spacelike embeddings, and Lagrange multipliers which serve to enforce the harmonic gauge in the action, or by a reduced space in which the multipliers are eliminated. The approach used here is applicable to any generally covariant theory and to any coordinate conditions. The physical interpretation of the diffeomorphism Hamiltonians is discussed and compared with the analogous interpretation given by …

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Exact And Asymptotic Scaling Solutions For Fragmentation With Mass Loss, M. Cai, Boyd F. Edwards, H. Han Jan 1991

Exact And Asymptotic Scaling Solutions For Fragmentation With Mass Loss, M. Cai, Boyd F. Edwards, H. Han

All Physics Faculty Publications

Exact and asymptotic solutions to a linear rate equation for fragmentation with mass loss are presented. Solutions for spatially discrete random bond annihilation illustrate the mutual exclusiveness of the fragmentation and recession terms in the rate equation. Exact solutions for deterministic equal fragment recession show that continuous mass loss between fragmentation events can be approximated by discrete mass loss during fragmentation events when this mass loss is small. Evidence that continuous and discrete mass loss preclude shattering mass loss, the loss of mass to zero-mass particles due to runaway fragmentation, is presented. General asymptotic scaling forms, general solutions reflecting arbitrary …

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Silicon (2p) Surface Core-Level Line Shape Of Si(111)—B, J. E. Rowe, G. K. Wertheim, D. Mark Riffe Jan 1991

Silicon (2p) Surface Core-Level Line Shape Of Si(111)—B, J. E. Rowe, G. K. Wertheim, D. Mark Riffe

All Physics Faculty Publications

Several recent structural studies of the Si(111)–B ((3)1/2×(3)1/2) surface have established that the boron atoms occupy substitutional sites in the second full Si layer and have Si adatoms directly above them. High‐resolution (∼80–100 meV) Si(2p) core‐level photoemission was used to determine the B‐induced perturbation of the surface Si atoms. The samples were prepared by surface segregation from Si(111) wafers (∼1.5 at. % B) after thermally removing the thin protective oxide layer on the surface. Photoemission spectra for photon energies from 110 to 140 eV show three peaks, indicative of at least two well‐separated spin‐orbit …

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A Deformation Theory Of Self-Dual Einstein Spaces, Charles G. Torre Jan 1991

A Deformation Theory Of Self-Dual Einstein Spaces, Charles G. Torre

All Physics Faculty Publications

The self-dual Einstein equations on a compact Riemannian 4-manifold can be expressed as a quadratic condition on the curvature of an $SU(2)$ (spin) connection which is a covariant generalization of the self-dual Yang-Mills equations. Local properties of the moduli space of self-dual Einstein connections are described in the context of an elliptic complex which arises in the linearization of the quadratic equations on the $SU(2)$ curvature. In particular, it is shown that the moduli space is discrete when the cosmological constant is positive; when the cosmological constant is negative the moduli space can be a manifold the dimension of which …

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Gaussian Reference Fluid And Interpretation Of Quantum Geometrodynamics, Karel Kucha, Charles G. Torre Jan 1991

Gaussian Reference Fluid And Interpretation Of Quantum Geometrodynamics, Karel Kucha, Charles G. Torre

All Physics Faculty Publications

The Wheeler-DeWitt equation of vacuum geometrodynamics is turned into a Schrödinger equation by imposing the normal Gaussian coordinate conditions with Lagrange multipliers and then restoring the coordinate invariance of the action by parametrization. This procedure corresponds to coupling the gravitational field to a reference fluid. The source appearing in the Einstein law of gravitation has the structure of a heat-conducting dust. When one imposes only the Gaussian time condition but not the Gaussian frame conditions, the heat flow vanishes and the dust becomes incoherent. The canonical description of the fluid uses the Gaussian coordinates and their conjugate momenta as the …

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Ionospheric Physics, Jan Josef Sojka Jan 1991

Ionospheric Physics, Jan Josef Sojka

All Physics Faculty Publications

The author has taken a parochial view of the subject matter
under the title of ionospheric physics. Physics is used as the
key to separating this section of the aeronomy review from the
other aeronomy reports. Specifically, work categorized as
chemistry, optical emissions, and thermosphere will not be
reviewed in this section. However, coupling to the
thermosphere and more specifically to the magnetosphere is
considered. A brief section is also included on active
experiments which is a productive area in plasma physics and
also to some extent in ionospheric physics, but one that has
fallen on hard times with regard …

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Field-Aligned Current Associated With A Distorted Two-Cell Convection Pattern During Northward Interplanetary Magnetic Field, Lie Zhu, Robert W. Schunk, Jan Josef Sojka Jan 1991

Field-Aligned Current Associated With A Distorted Two-Cell Convection Pattern During Northward Interplanetary Magnetic Field, Lie Zhu, Robert W. Schunk, Jan Josef Sojka

All Physics Faculty Publications

A systematic study of the influence of the ionospheric conductance on the field-aligned current associated with a distorted two-cell convection pattern during northward interplanetary magnetic field (IMF) has been conducted. Our modeling results indicate that the NBZ current can be associated with the distorted two-cell convection for most of the ionospheric conductivity conditions. It is shown that the conductivity conditions related to the seasonal variation and the aurora activity can significantly influence the basic features of the field-aligned current associated with a distorted two-cell convection pattern. It is found that the increase of the field-aligned current in the polar cap …

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Revised Global Model Of Thermosphere Winds Using Satellite And Ground-Based Observations, A E. Hedin, M A. Biondi, R G. Burnside, G Hernandez, R M. Johnson, T L. Killeen, C Mazaudier, J W. Meriwether, J E. Salah, R W. Smith, N W. Spencer, Vincent B. Wickwar, T S. Virdi Jan 1991

Revised Global Model Of Thermosphere Winds Using Satellite And Ground-Based Observations, A E. Hedin, M A. Biondi, R G. Burnside, G Hernandez, R M. Johnson, T L. Killeen, C Mazaudier, J W. Meriwether, J E. Salah, R W. Smith, N W. Spencer, Vincent B. Wickwar, T S. Virdi

All Physics Faculty Publications

Thermospheric wind data obtained from the Atmosphere Explorer E and Dynamics Explorer 2 satellites have been combined with wind data for the lower and upper thermosphere from ground-based incoherent scatter radar and Fabry-Perot optical interferometers to generate a revision (HWM90) of the HWM87 empirical model and extend its applicability to 100 km. Comparison of the various data sets with the aid of the model shows in general remarkable agreement, particularly at mid and low latitudes. The ground-based data allow modeling of seasonal/diurnal variations, which are most distinct at mid latitudes. While solar activity variations are now included, they are found …

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A Superconducting Compact Hydrogen Maser Resonator, David B. Opie Jan 1991

A Superconducting Compact Hydrogen Maser Resonator, David B. Opie

Dissertations, Theses, and Masters Projects

The discovery of high critical temperature superconductors (HTSC) has raised the temperature at which the greatly reduced surface resistance, characteristic of superconducting materials, may be exploited. For microwave frequencies below 100 GHz, the surface resistance, R{dollar}\sb{lcub}s{rcub}{dollar}, at liquid nitrogen temperatures (77K) of the new HTSC materials is found to be better than copper measured at the same temperature and frequency. Consequently, the miniaturization of passive microwave components will be among the first applications of these new materials. This dissertation details the development, testing and evaluation of a superconducting compact hydrogen maser resonator made from electrophoretic Y{dollar}\sb1Ba\sb2Cu\sb3{dollar}O{dollar}\sb{lcub}7-\delta{rcub}{dollar} (YBCO). Such a resonator …

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Completely Bootstrapped Tokamak, Richard Henry Weening Jan 1991

Completely Bootstrapped Tokamak, Richard Henry Weening

Dissertations, Theses, and Masters Projects

A fundamental requirement for the successful operation of a tokamak is the maintenance of a toroidal electric current within the tokamak plasma itself. Maintaining this internal plasma current can be a very difficult technological problem. In this work, a well-known but non-standard method for maintaining the tokamak current called the bootstrap effect is discussed. The bootstrap effect occurs when a fusion plasma is near thermonuclear conditions, and allows the tokamak to greatly amplify its electric current.;Because the bootstrap effect amplifies but does not create a plasma current, it has long been argued that a completely bootstrapped tokamak is not possible. …

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Pretransitional Optical Activity In Chiral Smectic Liquid Crystals, K. C. Frame, J. L. Walker, Peter J. Collings Jan 1991

Pretransitional Optical Activity In Chiral Smectic Liquid Crystals, K. C. Frame, J. L. Walker, Peter J. Collings

Physics & Astronomy Faculty Works

Pretransitional optical activity measurements in smectic liquid crystals of both law and high chirality are reported. In the low chirality sample, p-(n-(decyloxybenzylidene)-p-amino-(2-methylbutyl)cin-namate (DOBAMBC), the results indicate that the optical activity in both the isotropic phase just above the smectic A phase and in the smectic A phase just above the smectic C* phase can be explained in terms of a Landau-deGennes free energy with no coupling between the chiral modes. In the high chirality sample, 1-methylheptyl 4′-[(4″-tetradecyloxyphenyl)propioloyloxy]biphenyl-4-carboxylate (14P|M7), the data in the isotropic phase above the recently discovered smectic A* phase cannot be explained in this way, even when coupling …

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K-Shell Ionization Measurements For Light Incident Icons, Rahul Mehta, George Bissinger Jan 1991

K-Shell Ionization Measurements For Light Incident Icons, Rahul Mehta, George Bissinger

Journal of the Arkansas Academy of Science

The ionization of the K-shell in targets of copper, silver, dysprosium and gold was investigated with incident ion beams of proton and helium ions in the range 0.5 MeV/u to 3 MeV/u. The x-rays were detected by a HpGe detector. K-shell x-ray production cross section were determined by normalization of the x-ray yield to the incident beam flux, the Rutherford-scattered ions and the nuclear-Coulomb excited gamma ray yield. The multiple normalization procedures minimize the errors in these cross section measurements. The data are compared with the predictions of the ECPSSR theory for K-shell ionization. The atomic number dependence of these …

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Defect Structure, Nonstoichiometry, And Phase Stability Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, M. M. Nasrallah, Don M. Sparlin Jan 1991

Defect Structure, Nonstoichiometry, And Phase Stability Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, M. M. Nasrallah, Don M. Sparlin

Materials Science and Engineering Faculty Research & Creative Works

The dependence of the defect structure of Ca-doped YCrO3 on oxygen activity and temperature was investigated by high temperature thermogravimetric measurements. Defect models developed from electrical conductivity data obtained in a previous study were used to interpret the thermogravimetric data. A correlation was found between the electrical conductivity and the thermogravimetric data which suggested that these data were concomitantly dependent on the acceptor dopant and oxygen vacancy dependance of the thermodynamic parameters. Kröger-Vink type diagrams showing the regions of stability with respect to oxygen activity and temperature were constructed. The TGA data show that Ca-doped YCrO3 is even …

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Quantum Interference In Clothed-Ion-Atom Binary Peak Structures, C. O. Reinhold, D. R. Schultz, Ronald E. Olson, C. Kelbch, R. Koch, H. Schmidt-Böcking Jan 1991

Quantum Interference In Clothed-Ion-Atom Binary Peak Structures, C. O. Reinhold, D. R. Schultz, Ronald E. Olson, C. Kelbch, R. Koch, H. Schmidt-Böcking

Physics Faculty Research & Creative Works

An impulse approximation for ionizing collisions of clothed ions with atoms is used to explain the origin of an anomalous oscillation in the ejected electron spectrum in the region of the binary peak. In addition, measurements which evidence this feature for 1-MeV/u U21+ ions colliding with helium are presented. It is shown that this behavior arises from interference structures in the elastic differential cross section for the scattering of target electrons from the impinging ion and that it is associated with the well-known phenomenon of rainbow scattering. © 1991 The American Physical Society.

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Fine‐Structure Mixing Within The Zn(43pj) Multiplet By Collisions With The Noble Gases, Xianming Han, J. F. Kelly Jan 1991

Fine‐Structure Mixing Within The Zn(43pj) Multiplet By Collisions With The Noble Gases, Xianming Han, J. F. Kelly

Scholarship and Professional Work - LAS

Measurements of rate coefficients for intramultiplet state transfer of Zn(4 3 P 1→4 3 P J’) by collisions with the rare gases are presented. The state‐to‐state binary rate coefficients are derived from least‐squares fittings of the time‐resolved triexponential behavior of the 4 3 P 1fluorescence. These rate coefficients were studied systematically over a temperature range of 690–1100 K in order to characterize the velocity dependence of the collisional coupling. The systematic behavior of the rate coefficients with varying temperature and noble gas species is qualitatively consistent with a nearly adiabatic coupling limit for noncrossing levels.

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Lightning: A Complex Natural Phenomenon That Defies Simple Analysis, Mostafa Hemmati Jan 1991

Lightning: A Complex Natural Phenomenon That Defies Simple Analysis, Mostafa Hemmati

Journal of the Arkansas Academy of Science

No abstract provided.

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Electric Field Induced Emission As A Diagnostic Tool For Measurement Of Local Electric Field Strengths, A. N. Dharamsi, K. H. Schoenbach Jan 1991

Electric Field Induced Emission As A Diagnostic Tool For Measurement Of Local Electric Field Strengths, A. N. Dharamsi, K. H. Schoenbach

Bioelectrics Publications

The phenomenon of electric field induced (EFI) emission is examined in several diatomic and polyatomic molecules. The possibility of using this phenomenon as a diagnostic tool to measure, nonintrusively, the strength and direction of local electric fields in plasmas is discussed. An estimate of the EFI signal emitted in a typical application plasma is given. This yields a lower bound on the detector sensitivity necessary to exploit EFI emission in practical applications. It is concluded that, at present, the EFI signal could be measured by some very sensitive infrared detection schemes available. Current progress in infrared detector technology, if maintained, …

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Nucleon Axial Vector Form Factors And Electromagnetic Transition Amplitudes In Perturbative Qcd, Jennifer L. Poor Jan 1991

Nucleon Axial Vector Form Factors And Electromagnetic Transition Amplitudes In Perturbative Qcd, Jennifer L. Poor

Dissertations, Theses, and Masters Projects

Values for the normal isovector axial vector form factor g$\sb{\rm A}$(Q$\sp2$) are calculated from the leading order perturbative QCD hard scattering amplitude and some previously reported models for the nucleon distribution amplitude, some of which have been derived from QCD sum rules. The values obtained from each of the distribution amplitudes gives a result that is consistent with the data extrapolated to high momentum transfer. The axial vector form factor is around one and one half times the proton's magnetic form factor in all the models which is also in accord with the data. We also calculate the isoscalar axial …

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Low-Energy Collisions Of Negative Ions With Atomic Hydrogen, Michael A. Huels Jan 1991

Low-Energy Collisions Of Negative Ions With Atomic Hydrogen, Michael A. Huels

Dissertations, Theses, and Masters Projects

Total cross sections for charge transfer and electron detachment for collisions of a variety of negative ions with atomic hydrogen have been separately determined for laboratory collision energies ranging from about 5 eV to 500 eV. The experiments are performed with an apparatus that utilizes a crossed-beam configuration with a radio-frequency discharge as the source of atomic hydrogen.;For collisions of H{dollar}\sp-{dollar}(D{dollar}\sp-{dollar}) with H the charge transfer cross sections increase monotonically with decreasing energy and display an isotope effect. at the lowest collision energies, the electron detachment cross sections are about one order of magnitude smaller than those for charge transfer; …

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Photodetachment Of Hydride Ion In Perpendicular Electric And Magnetic Fields, Aaron David Peters Jan 1991

Photodetachment Of Hydride Ion In Perpendicular Electric And Magnetic Fields, Aaron David Peters

Dissertations, Theses, and Masters Projects

A simple analytic formula for the photodetachment cross section of H$\sp{-}$ in perpendicular electric and magnetic fields is obtained. Oscillations in the spectrum are predicted by the formula, and these oscillations are correlated with closed classical orbits. We point out that the quantum mechanical derivation, using a stationary phase approximation, is in complete agreement with the three-dimensional semiclassical solution to the problem.

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Nuclear Magnetic Resonance Studies Of Amorphous Nickel-Zirconium Hydrides, Harris Clarence Hoke Jr. Jan 1991

Nuclear Magnetic Resonance Studies Of Amorphous Nickel-Zirconium Hydrides, Harris Clarence Hoke Jr.

Dissertations, Theses, and Masters Projects

This research deals with one aspect of the scientific field of hydrogen in metals. The study of hydrogen in metals is technologically important for many reasons, among them is the use of hydrogen in metals to store energy. Hydrogen related energy technology is particularly attractive because hydrogen can be extracted from water, our most abundant resource, and can be used without any pollution. Metal hydrides may one day be widely used for automotive propulsion in cars, in batteries, and many other energy conversion devices. Amorphous NiZr is particularly interesting for hydrogen storage because high concentrations of hydrogen can be sorbed …

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Feq⁺+ H, H2and He Electron Loss And He2++ H(N = 1, 2) Electron Capture Cross Sections: Processes Of Interest In Fusion Plasmas, D. R. Schultz, L. Meng, C. O. Reinhold, Ronald E. Olson Jan 1991

Feq⁺+ H, H2and He Electron Loss And He2++ H(N = 1, 2) Electron Capture Cross Sections: Processes Of Interest In Fusion Plasmas, D. R. Schultz, L. Meng, C. O. Reinhold, Ronald E. Olson

Physics Faculty Research & Creative Works

Cross sections have been calculated utilizing the classical trajectory Monte Carlo method for collisional processes of special interest to plasma fusion research. Specifically, H1H2and He total electron loss cross sections for the impact by Feq+(1 < q < 26) impurity ions, in the energy range of 50 to 500keV/u, are presented. These results illustrate a clear departure for low charge states (q < 10) from scaling of the cross section with projectile charge (q). Further, cross sections for electron capture from both the ground and n = 2 states of H by 30 to lOOkeV/u He2+impact are tabulated as function of final n-level, yielding information for neutral beam heating models. © 1991 IOP Publishing Ltd.

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Electrical Conductivity, Seebeck Coefficient And Defect Chemistry Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, Don M. Sparlin, M. M. Nasrallah Jan 1991

Electrical Conductivity, Seebeck Coefficient And Defect Chemistry Of Ca-Doped Ycro3, G. F. Carini, Harlan U. Anderson, Don M. Sparlin, M. M. Nasrallah

Materials Science and Engineering Faculty Research & Creative Works

The electrical transport behavior and defect structure of Ca-doped YCrO3 were studied using electrical conductivity and Seebeck coefficient measurements as a function of oxygen activity and temperature. Defect models derived from the electrical conductivity data were found to adequately relate the concentration of charge carriers to the acceptor dopant and oxygen vacancy concentrations. Thermodynamic properties were calculated and found to be consistent with the model. Activation energy and carrier mobility data were also obtained. The analysis of the electrical conductivity, Seebeck and mobility data suggest that the conduction process in Ca-doped YCrO3 occurs via the small polaron hopping …

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U(1) String Tension, Arthur F. Griesser Jan 1991

U(1) String Tension, Arthur F. Griesser

Dissertations, Theses, and Masters Projects

The long distance force between quarks in the U(1) approximation to quantum chromodynamics is calculated on a home made reduced instruction set computer optimized for that purpose. It is found that previous calculations were in error by as much as 85% due to contamination by the Coulomb interaction. The Coulomb constant, measured for the first time in this work, agrees with analytically obtained values.

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The Invention Of The Transistor, Bret E. Crawford Jan 1991

The Invention Of The Transistor, Bret E. Crawford

Graduate College Dissertations and Theses

Julius E. Lilienfeld filed for patents for three different designs for solid-state amplifying devices between 1926 and 1928, well before Bell Lab's discovery of the point-contact transistor in 1948. The American Physical Society named a prize in honor of Lilienfeld after receiving a substantial sum of money in 1982 from the will of his wife, Beatrice Lilienfeld, who believed her husband had not received sufficient credit for his scientific contributions. In order to investigate Lilienfeld's contribution to early efforts to replace the vacuum triode, we present the history surrounding these efforts, contributions and limitations of Lilienfeld's work, and details of …

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Direct Determination Of Molecular-Orbital Symmetry Of H2s Using Polarized X-Ray Emission, R. Mayer, Dennis W. Lindle, S. H. Southworth, P. L. Cowan Jan 1991

Direct Determination Of Molecular-Orbital Symmetry Of H2s Using Polarized X-Ray Emission, R. Mayer, Dennis W. Lindle, S. H. Southworth, P. L. Cowan

Chemistry and Biochemistry Faculty Research

X-ray emission from the molecule H2S is strongly polarized following excitation of a sulfur K-shell electron to an unoccupied subthreshold molecular orbital with a polarized x-ray beam. Changes in the polarization of the emission spectrum are observed as the incident beam's energy is swept across the subthreshold absorption resonance. The previously unresolved absorption resonance is shown experimentally to be primarily associated with a molecular orbital of b2 symmetry, but with a high-excitation-energy component due to an orbital with a1 symmetry. Satellite emission intensity is shown to depend on the primary photon energy and is therefore associated …

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Magnetic Field Strength Of Toroidal Plasma Equilibria, David Alan Garren Jan 1991

Magnetic Field Strength Of Toroidal Plasma Equilibria, David Alan Garren

Dissertations, Theses, and Masters Projects

The goal of nuclear fusion research is to confine a deuterium-tritium plasma at a sufficiently high temperature (15 keV) and density (3 $\times$ 10$\sp{20}$ m$\sp{-3}$) for a sufficient length of time (1 sec) to produce net fusion power. One means to attain the required plasma confinement is to embed the plasma within a magnetic field. The global structure of this magnetic field determines the variation of magnetic field strength within the surfaces of constant plasma pressure. This field strength variation in turn determines many of the stability and confinement properties of the plasma. This dissertation gives the first detailed exposition …

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Parametric Instability Of Supersonic Shear Layers Induced By Periodic Mach Waves, Fang Q. Hu, Christopher K. W. Tam Jan 1991

Parametric Instability Of Supersonic Shear Layers Induced By Periodic Mach Waves, Fang Q. Hu, Christopher K. W. Tam

Mathematics & Statistics Faculty Publications

It is suggested that parametric instability can be induced in a confined supersonic shear layer by the use of a periodic Mach wave system generated by a wavy wall. The existence of such an instability solution is demonstrated computationally by solving the Floquet system of equations. The solution is constructed by means of a Fourier-Chebyshev expansion. Numerical convergence is assured by using a very large number of Fourier and Chebyshev basis functions. The computed growth rate of the induced flow instability is found to vary linearly with the amplitude of the mach waves when the amplitude is not excessively large. …

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Structure And Optical Characterization Of Znxcd1-Xte Thin Films Prepared By The Close Spaced Vapor Transport Method, David D. Allred, Jesus González-Hernández, O. Zelaya, J. G. Mendoza-Alverez, E. López-Cruz, D. A. Pawlik Jan 1991

Structure And Optical Characterization Of Znxcd1-Xte Thin Films Prepared By The Close Spaced Vapor Transport Method, David D. Allred, Jesus González-Hernández, O. Zelaya, J. G. Mendoza-Alverez, E. López-Cruz, D. A. Pawlik

Faculty Publications

Zinc cadmium telluride (ZnxCd1-xTe) solid solution films with 0≤x≤0.12 were deposited by the close spaced vapor transport method and characterized using photoluminescence, x-ray diffraction, and scanning electron microscopy. The two former techniques indicate that films with high crystalline quality can be prepared with moderate substrate temperatures and low argon pressures. Under these conditions deposition rates of up to 1000 Å/s are achieved and Zn concentration in the film is the same as that of the source. The electron micrographs show grain sizes comparable to the film thickness.

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The Transmittances Of Thin Polymer Films And Their Suitability As A Supportive Substrate For A Soft X-Ray Solar Filter, Memorie Williams, Evan Hansen, A. Reyes-Mena, David D. Allred Jan 1991

The Transmittances Of Thin Polymer Films And Their Suitability As A Supportive Substrate For A Soft X-Ray Solar Filter, Memorie Williams, Evan Hansen, A. Reyes-Mena, David D. Allred

Faculty Publications

This paper discusses soft x-ray filter designs for the Brigham Young University "Goldhelox Project". Three polymers intended for use as a supportive substrate for a soft x-ray solar filter, having a passband centered at 171 angstroms are examined. The use of polymer substrates is examined because of vibrational and mechanical stresses associated with the shuttle launch, preventing the use of a free standing filter, and because of Goldhelox's special need to locate the filter near the imaging plane. The uniform consistency of a polymer support will prevent any imaging of the filter support structure, as would occur if a traditional …

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