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The Effects Of A Mandatory Early Shutdown Of Maine Yankee, Maine State Planning Office

Maine Collection

The Effects of a Mandatory Early Shutdown of Maine Yankee

Maine State Planning Office - Richard Silkman, Director (September 1987).

Contents: Introduction / Legal Issues / Economic Issues / Health and Environmental Issues / Conclusions / Appendices

Structural And Superconducting Properties Of Orientation-Ordered Y1Ba2Cu3O7-X Films Prepared By Molecular-Beam Epitaxy , J. Kwo, T.C. Hsieh, R.M. Fleming, M. Hong, Sy_Hwang Liou, B.A. Davidson, L.C. Feldman

Sy-Hwang Liou Publications

Superconducting Y₁Ba₂Cu₃O_7-x films were produced by metal molecular-beam epitaxy with one electron beam and two thermal cells and a molecular oxygen-gas source. The films were epitaxially grown on SrTiO₃ (100) with an a-axis orientation perpendicular to the plane, and b and c axes ordered in the plane. A sharp resistive superconducting transition with T_c (R=0) at 82 K was obtained. A lower limit of the average J_c in the plane is 10³ A/cm² at 77 K, 5×10⁴ A/cm² at 70 K, and 10 …

Square-Lattice Ising Model In A Weak Uniform Magnetic Field: Renormalization Group Analysis, Miron Kaufman

Physics Faculty Publications

For the two-dimensional ferromagnetic Ising critical point, I show that the known values of the critical exponents imply the absence of logarithms of the reduced temperature in the leading contributions to any field derivative of the free energy at zero magnetic field. For the square-lattice Ising antiferromagnet in a weak magnetic field, I compute the critical line T_c(H)=T_c⁰(1-0.038 023 259H²) and the leading contribution to the susceptibility χ=0.014 718 006 6H²ln(1/ǁtǁ), where t is the reduced temperature.

Energy-Transfer Theory For The Classical Decay Rates Of Molecules At Rough Metallic Surfaces, P.T. Leung, Thomas F. George

Physics Faculty Publications and Presentations

The problem of the decay rates for molecules at rough metallic surfaces is considered, where the classical electromagnetic energy-transfer theory of Chance, Prock, and Silbey for a flat surface is generalized to the case of a rough boundary. A dynamical theory is constructed through the combination of the Sommerfeld antenna theory and the integral equation formalism of Maxwell's equations at rough boundaries established mainly by Maradudin, Mills, and Agarwal. Perturbative solutions are obtained and numerical results are given with reference to a shallow sinusoidal grating surface. The results, when compared with those obtained previously from the application of the image …

Electron Beam Effects In The Analysis Of Compound Semiconductors And Devices, Nancy Burnham, Ll Kazmerski, Ab Swartzlander, Aj Nelson, Se Asher

Nancy A. Burnham

The effects of electron beams on the analysis of CuInSe2surfaces are examined in this paper. Potential changes in the surface chemistry—including oxidation and desorption—under a range of incident probe conditions, are investigated for possible artifactual information generation. Emphasis is placed on the relationships between beam conditions and oxygen chemisorption and physisorption, since oxygen treatments of devices utilizing this semiconductor are critical to performance. Single crystals and polycrystalline thin films are analyzed and compared to establish the beam‐induced phenomena.

Superconducting Y-Ba-Cu-O Oxide Films By Sputtering, M. Hong, Sy_Hwang Liou, J. Kwo, B.A. Davidson

Sy-Hwang Liou Publications

We have prepared superconducting thin films of Y-Ba-Cu-O with T_c onsets above 95 K by both diode and magnetron sputtering. Films with full superconductivity (R=0) at 85 K have been produced by dc magnetron sputtering. The compositions of the films are fairly uniform across an area 50 mm in diameter and through the film thickness. Structural properties of the films were studied by x-ray diffraction. Critical current densities in the range of 3000 to 10⁴ A/cm² have been measured at 4.2 K. Applied Physics Letters is copyrighted by The American Institute of Physics.

N-Level Quantum Systems With Su(2) Dynamic Symmetry, Foek T. Hioe

Physics Faculty/Staff Publications

We present an analytic solution of the coherent evolution of a laser-driven N-level quantum system that possesses an SU(2) dynamic symmetry.

Interaction Of Hg Overlayers With An Ag(100) Surface, Peter A. Dowben, Y.J. Kime, Shikha Varma, M. Onellion, J.L. Erskine

Peter Dowben Publications

The electronic band structure of one, two, and five monolayers of Hg on Ag(100) has been investigated by angle-resolved photoemission. Hg overlayers on Ag(100) form metastable structures that develop via Frank–van der Merwe growth modes. Hg-Hg hybridization results in the formation of a two-dimensional band structure while hybridization of Hg with the underlying Ag(100) substrate results in the adoption of bulklike characteristics for some Hg-induced bands. The Hg-Hg as well as Hg-Ag interactions are discussed.

Transition-Matrix Theory For Two–Photon Ionization Of Rare–Gas Atoms And Isoelectronic Ions With Application To Argon, Anthony F. Starace, Tsin-Fu Jiang

Anthony F. Starace Publications

A transition-matrix theory for two-photon ionization processes in rare-gas atoms or isoelectronic ions is presented. Uncoupled ordinary differential equations are obtained for the radial functions needed to calculate the two-photon transition amplitude. The implications of these equations are discussed in detail. In particular, the role of correlations involving virtually excited electron pairs, which are known to be essential to the description of single-photon processes, is examined for multiphoton ionization processes. Additionally, electron scattering interactions between two electron-hole pairs are introduced into our transition amplitude in the boson approximation since these have been found important in two-photon ionization of xenon by …

29th Rocky Mountain Conference

Rocky Mountain Conference on Magnetic Resonance

Program and abstracts from the 29th annual meeting of the Rocky Mountain Conference, co-sponsored by the Rocky Mountain Section of the Society for Applied Spectroscopy and the Rocky Mountain Chromatography Discussion Group. Held in Denver, Colorado, August 2-6, 1987.

Simple Model For The Resonant Vibrational Excitation Of Molecules And Its Application To Li2 And N2, J M. Wadehra, P J. Drallos

Physics and Astronomy Faculty Research Publications

A simple model for the resonant vibrational excitation of a molecule by electron impact is proposed in which the potential curves of the electronic states of the molecule and its resonant anion are replaced by those of linear harmonic oscillators of arbitrary frequencies and equilibrium internuclear separations. A closed-form expression for the excitation amplitude is derived. Useful recursion relations among amplitudes are obtained which allow convenient evaluation of cross sections for any inelastic or superelastic vibrational transition. The model is used to generate the cross sections for vibrational excitation of Li_2 and N_2 by the impact of low-energy electrons.

Microwave Absorption In The Superconducting And Normal Phases Of Y-Ba-Cu-O, R. Durný, J. Hautala, Stephen Ducharme, B. Lee, O.G. Symko, P.C. Taylor, D.J. Zheng, J.A. Xu

Stephen Ducharme Publications

Microwave absorption in a dc magnetic field up to 12 kG, attributed to nonequilibrium contributions to the ac susceptibility, appears at T_c as the sample is cooled. ESR measurements of Y-Ba-Cu-O show that Cu²⁺ exists only in the fraction of the sample which is not superconducting in a distorted octahedral surrounding.

Contributions Of Higher Partial Waves To The Elastic Scattering Amplitude For Various Long Range Interactions, J M. Wadehra, Sultana N. Nahar

Physics and Astronomy Faculty Research Publications

The contributions of higher partial waves to the elastic scattering amplitude are dominated by long-range interactions which fall off as r^(−n) as r→∞. Closed-form expressions for the contributions of higher partial waves (2l>n-3) to the scattering amplitude for various long-range interactions (n ranging from 3 to 8) are presented.

Static Magnetic Field Models Consistent With Nearly Isotropic Plasma Pressure, Harlan E. Spence, Margaret G. Kivelson, Raymond J. Walker

Physics & Astronomy

Using the empirical magnetospheric magnetic field models of Tsyganenko and Usmanov (TU), we have determined the self-consistent plasma pressure gradients and anisotropies along the midnight meridian in the near-Earth magnetosphere. By “inverting” the magnetic field, we determine what distributions of an anisotropic plasma, confined within the specified magnetic field configuration, are consistent with the magnetohydrostatic equilibrium condition, J × B = ∇ · P. The TU model, parameterized for different levels of geomagnetic activity by the Kp index, provided the magnetic field values from which J × B was numerically evaluated. A best fit solution was found that minimized the …

The Binary Cepheid Dl Cas And The Open Cluster Ngc 129, Hugh C. Harris, Douglas L. Welch, Robert P. Kraft, Edward G. Schmidt

Edward Schmidt Publications

The Cepheid DL Cas and the nonvariable supergiant Star A are confirmed as members of NGC 129, and both are found to be spectroscopic binaries with orbital periods of a few years. Periods and orbits are determined for both stars. Star A is apparently rotating; tidal interaction with its companion is discussed and then rejected as the probable cause of the rotation. The membership of other stars and the velocity of the cluster are redetermined.

Cp Violation In K-]3-Pi, Jf Donoghue, Br Holstein, G Valencia

Barry R Holstein

No abstract provided.

Observation Of Steepening In Electron Plasma Waves Driven By Stimulated Raman Backscattering, Donald Umstadter, R. Williams, C. Clayton, C. Joshi

Donald Umstadter Publications

Harmonics of plasma waves excited by CO₂-laser–induced stimulated Raman scattering have been observed by frequency- and wave-number-resolved ruby Thomson scattering. Measurements of their relative amplitudes agreed with predictions of nonlinear warm-plasma wave-steepening theory up to the maximum observed amplitude of the fundamental component, ñ₁/n₀=16%.

Theoretical Studies Of Electron Transfer In Metal Dimers: Xy+→X+Y, Where X, Y=Be, Mg, Ca, Zn, Cd, Robert J. Cave, David V. Baxter, William A. Goddard Iii, John D. Baldeschwieler

All HMC Faculty Publications and Research

The electronic matrix element responsible for electron exchange in a series of metal dimers was calculated using ab initio wave functions. The distance dependence is approximately exponential for a large range of internuclear separations. A localized description, where the two nonorthogonal structures characterizing the electron localized at the left and right sites are each obtained self‐consistently, is found to provide the best description of the electron exchange process. We find that Gaussian basis sets are capable of predicting the expected exponential decay of the electronic interactions even at quite large internuclear distances.

Three-State Model Driven By Two Laser Beams, C. E. Carroll, Foek T. Hioe

Physics Faculty/Staff Publications

We use a three-state model for an atom or molecule in which two transitions are simultaneously driven by the oscillating electric fields of two laser beams. The amplitudes and detunings of the applied oscillating fields vary during the optical pulse, which can cause transitions from one state to another. For some special cases not previously known, the transition probabilities and probabilities of no transition are obtained analytically. We give conditions for complete transfer of the atomic population from one state to another, and for complete return to the initial state.

Observation Of Possible Supercondictivity At 230 K, C. Y. Huang, L. J. Dries, P. H. Hor, R. L. Meng, C. W. Chu, Richard B. Frankel

Physics

Recently, Chu announced the observation of sharp drops of up to two orders of magnitude in the resistance of several Y-, Sc- and La-based multi-phase Ba–Cu oxide samples at temperatures as high as 240 K. The resistance drops reported did not survive the thermal cyclings for magnetic measurements. Later, M. H. Cohen (personal communication) reported similar anomalies in some Y-based oxides. In the absence of zero resistivity and evidence for the Meissner effect, the sharp resistance drops have been taken only as an indication of the possible existence of superconductivity at these unusually high temperatures. More recently, Chen et al. …

Saddle-Point Electrons In Ionizing Ion-Atom Collisions, R. E. Olson, Timothy J. Gay, H. G. Berry, V. D. Irby

Timothy J. Gay Publications

We have studied H⁺+He ionizing collisions, and find that electrons stranded between the two postcollision Coulomb centers dominate the ejected-electron spectra for intermediate (~100 keV) projectile energies. The importance of these electrons is clearly established by our classical calculations which are in qualitative agreement, in both shape and magnitude, with experimental spectra taken by us, and with earlier measurements. These ‘‘saddle-point’’ electrons are produced by a classically understandable mechanism, and are unambiguously observed at nonzero scattering angles.

The Stability And Decomposition Of Gaseous Chloroferrocenes, S. Barfuss, M. Grade, W. Hirschwalde, W. Rosinger, N.M. Boag, D.C. Driscoll, Peter A. Dowben

Peter Dowben Publications

The ionic and neutral decomposition of gaseous ferrocene, 1, 1'-dichloroferrocene and 1, 1', 2,2'- tetrachloroferrocene, has been investigated via photon and electron induced ionization mass spectroscopy. The thermodynamic cycle incorporating the ionic and neutral fragments of ferrocene has been constructed. Elimination reactions in the decomposition of the dichloroferrocene and tetrachloroferrocenes have been identified.

Molecular Lifetimes In The Presence Of Periodically Roughened Metallic Surfaces, P.T. Leung, Z. C. Wu, Daniel A. Jelski, Thomas F. George

Physics Faculty Publications and Presentations

The lifetimes of molecules located close to a sinusoidal grating surface are studied within a classical phenomenological model. The contribution of surface roughness to the molecular decay rate is attributed to the discrepancy between the experiments of Rossetti and Brus and the theory of Chance, Prock, and Silbey. It is found that surface roughness can either enhance or diminish the flat-surface value for the decay rate depending on the emitting frequency, molecule-surface distance, and the molecular orientation.

Surface Conductance Of A Copper Wire In A Fluid At High Pressure, Daniel L. Decker

Faculty Publications

The three-dimensional flow of heat in a wire carrying a current and immersed in a liquid is solved in detail. Using this exact result the surface conductance of copper in petroleum ether has been measured as a function of pressure to 40 kbars. The measured surface conductance for copper in a fluid is very small, justifying approximations which yield results that are in agreement with a simplified one-dimensional heat-flow problem. Surprisingly, even at 40 kbars pressure a very large fraction of the joule heating within a wire with a length-to-diameter ratio of ~100 is dissipated through the ends of the …

Measurement Of The Condensation Coefficient Of Water In The Umr Cloud Simulation Chamber, Daniel R. White, James L. Kassner, John C. Carstens, Donald E. Hagen, John L. Schmitt, Darryl J. Alofs, A. R. Hopkins, Max B. Trueblood, M. W. Alcorn

Physics Faculty Research & Creative Works

Measurements of the condensation coefficient of water under conditions closely approximating those in natural atmospheric cloud have been made in the cooled-wall UMR cloud simulation chamber. Current measurements disclose a value of condensation coefficient near unity at the outset of the experiment, generally decreasing to lower values (~ .01) as the experiment progresses. The significance of the magnitude of condensation coefficient in atmospheric cloud is briefly discussed.

Superconductivity At 155 K, David D. Allred, S. R. Ovshinsky, R. T. Young, G. Demaggio, G. A. Van Der Leeden

Faculty Publications

Transition to a superconducting zero-resistance state at 155 K is observed for the first time in bulk material. A new five-element compound has been synthesized with nominal composition Y1Ba2Cu3F2Oy. Fluorine plays a critical role in achieving this effect. X-ray diffraction and electron microprobe analysis indicate that the samples are multiphasic. Evidence is presented that the samples contain superconducting phases with onset temperatures considerably above 155 K. Magnetic measurements suggest a flux-trapping effect below 260 K, and diamagnetic deviations from Curie-Weiss behavior in the range from 250 K≤T≤100 K indicate that Meissner effect in a small superconducting volume fraction.

Simulation Of Normal Rb2Zncl4 Near The Incommensurate Transition, P. J. Edwardson, V. Katkanant, John R. Hardy, L. L. Boyer

John R. Hardy Papers

The purposes of the reported computer simulation of the normal (high-temperature) phase of rubidium tetrachlorozincate are to understand the disordered structure in that phase and to investigate the possibility that the transition, upon cooling, from the normal phase to one with an incommensurate modulation is associated with a change from the disordered structure to an ordered one. The simulation of the dynamics of 168 ions in a periodic structure begins from a slight perturbation of a structure that is determined by minimization of the potential energy within the constraints of the experimentally determined average symmetry. Rigid ions with short-range interactions …

Antiphase Domain Boundaries In The Superconducting Phase Of The Y-Ba-Cu-O System, C.H. Chen, J. Werder, Sy_Hwang Liou, M. Hong

Sy-Hwang Liou Publications

Transmission-electron-microscopy examination of the superconducting phase of the Y-Ba-Cu-O system reveals the presence of dense antiphase boundaries. The structure of the superconducting phase was determined to be orthorhombic with space group Pm2m. The orthorhombic a and b axes are found to alternate across the antiphase boundary which runs parallel to the [110] direction.

Break-Junction Tunneling Measurements Of The High-TC Superconductor Y1Ba2Cu3O9- Δ , J. Moreland, J.W. Ekin, L.F. Goodrich, T.E. Capobianco, A.F. Clark, J. Kwo, M. Hong, Sy_Hwang Liou

Sy-Hwang Liou Publications

Current-voltage tunneling characteristics in a high-critical-temperature superconducting material containing predominately Y₁Ba₂Cu₃O_{9- δ} have been measured using the break-junction technique. Sharp gap structure was observed, with the largest superconductive energy gap measured to be Δ=19.5±1 meV, assuming a superconductor-insulator-superconductor junction. This energy gap corresponds to 2Δ/k_BT_c=4.8 at T=4 K, for a critical temperature of 93 K (midpoint of the resistive transition).

High Rydberg States Of An Atom In Parallel Electric And Magnetic Fields, Robert L. Waterland, John B. Delos, M. L. Du

Arts & Sciences Articles

We have calculated the energy spectrum of a highly excited atom in parallel electric and magnetic fields. The eigenvalues were obtained by semiclassical quantization of action variables calculated from first-order classical perturbation theory. For the field strengths studied, the electron moves on a Kepler ellipse whose orbital parameters evolve slowly in time, and first-order perturbation theory reduces the problem to just one degree of freedom. Action variables were calculated from perturbation theory and the eigenvalues were obtained by semiclassical quantization of the action. The semiclassical analysis leads directly to a correlation diagram which connects the eigenstates of the Stark effect …