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Multiflavor Massive Schwinger Model With Non-Abelian Bosonization, Joseph Schechter, David Delphenich Apr 1997

Multiflavor Massive Schwinger Model With Non-Abelian Bosonization, Joseph Schechter, David Delphenich

Physics - All Scholarship

We revisit the treatment of the multiflavor massive Schwinger model by non-Abelian Bosonization. We compare three different approximations to the low-lying spectrum: i) reading it off from the bosonized Lagrangian (neglecting interactions), ii) semi-classical quantization of the static soliton, iii) approximate semi-classical quantization of the ``breather'' solitons. A number of new points are made in this process. We also suggest a different ``effective low-energy Lagrangian'' for the theory which permits easy calculation of the low-energy scattering amplitudes. It correlates an exact mass formula of the system with the requirement of the Mermin-Wagner theorem.

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Electron Acceleration By A Laser Wakefield In A Relativistically Self-Guided Channel, R. Wagner, Shouyuan Chen, Anatoly Maksimchuk, Donald P. Umstadter Apr 1997

Electron Acceleration By A Laser Wakefield In A Relativistically Self-Guided Channel, R. Wagner, Shouyuan Chen, Anatoly Maksimchuk, Donald P. Umstadter

Donald Umstadter Publications

Acceleration of electrons to relativistic energies by a multidimensional self-modulated laser wakefield is discussed. Above a power threshold, a relativistically self-guided channel from an intense ultrashort laser pulse (l∼4×1018 W/cm2, λ = 1 μm, τ = 400 fs) was found to increase the laser propagation distance, decrease the electron beam divergence, and increase the energy of the electrons. These electron beam effects occurred even though the propagation distance became significantly longer than the conventional dephasing length.

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Generalization Of The Bound State Model, Joseph Schechter, Masayasu Harada, Francesco Sannino, Herbert Weigel Apr 1997

Generalization Of The Bound State Model, Joseph Schechter, Masayasu Harada, Francesco Sannino, Herbert Weigel

Physics - All Scholarship

In the bound state approach the heavy baryons are constructed by binding, with any orbital angular momentum, the heavy meson multiplet to the nucleon considered as a soliton in an effective meson theory. We point out that this picture misses an entire family of states, labeled by a different angular momentum quantum number, which are expected to exist according to the geometry of the three-body constituent quark model (for N_C=3). To solve this problem we propose that the bound state model be generalized to include orbitally excited heavy mesons bound to the nucleon. In this approach the missing angular momentum …

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Magnetic Hardening In Fept Nanostructured Films, J. Ping Liu, Yi Liu, C.P. Luo, Z.S. Shan Apr 1997

Magnetic Hardening In Fept Nanostructured Films, J. Ping Liu, Yi Liu, C.P. Luo, Z.S. Shan

David Sellmyer Publications

FePt films have been prepared by sputtering Fe/Pt multilayers onto glass or silicon substrates. The thickness of the Fe and Pt layers was adjusted with the Fe:Pt atomic ratio from about 1:1 to 2:1. Magnetic hardening is observed after heat treatment at elevated temperatures, which led to coercivity values exceeding 20 kOe in samples with an Fe:Pt ratio around 1.2:1. The hardening originates from the formation of the tetragonal FePt phase with high magnetocrystalline anisotropy and a favorable microstructure. Two-phase composite films containing hard and soft phases were obtained when the Fe:Pt ratio increased. Under optimized processing conditions, composite films …

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Correlation Of Switching Volume With Magnetic Properties, Microstructure, And Media Noise In Cocr(Pt)Ta Thin Films, C. Gao, Z.S. Shan, R. Malmhall, Yi Liu, H.J. Richter, A. Barney, G.C. Rauch, David J. Sellmyer Apr 1997

Correlation Of Switching Volume With Magnetic Properties, Microstructure, And Media Noise In Cocr(Pt)Ta Thin Films, C. Gao, Z.S. Shan, R. Malmhall, Yi Liu, H.J. Richter, A. Barney, G.C. Rauch, David J. Sellmyer

David Sellmyer Publications

The technique of "field sweep-rate dependence of coercivity" together with the delta-M curves, transmission electron microscopy, and media noise measurement have been employed to reveal the correlation among the magnetic switching volume, physical grain size, intergrain interaction, and noise properties. The switching volume for both CoCrTa and CoCrPtTa films was found to be ~ 15 nm in diameter, and weakly dependent on grain size and coercivity for the systems studied. In films with physical grain size larger than the switching volume, strong intergrain interaction and high media noise is observed. In films with the physical grain size close to the …

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Metamagnetic Domains And Dynamic Fluctuations In Febr2, O. Petracic, Christian Binek, Wolfgang Kleeman Apr 1997

Metamagnetic Domains And Dynamic Fluctuations In Febr2, O. Petracic, Christian Binek, Wolfgang Kleeman

Christian Binek Publications

The mixed phase and the regime of non-critical fluctuations of the magnetic phase diagram of FeBr2 is investigated by SQUID susceptometry and light diffraction techniques. The experiments seem to evidence instability of the tricritical point as conjectured recently. The observation of stripe domains and light diffraction below and above Tm = 4.6 K and the virtual continuation of the phase transition line to above Tm are in agreement with the occurrence of a critical endpoint at Tm and of a bicritical endpoint at T > Tm. ©1997 American Institute of Physics.

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Nanostructure And Magnetic Anisotropy Of Co/Au Multilayers, Yi Liu, Z.S. Shan, David J. Sellmyer Apr 1997

Nanostructure And Magnetic Anisotropy Of Co/Au Multilayers, Yi Liu, Z.S. Shan, David J. Sellmyer

David Sellmyer Publications

Multilayer Co/Au films were deposited on 40 nm Au underlayer by magnetron sputtering. The Co thickness is kept constant at 0.5 nm while the Au thickness is varied from 0.5 to 8 nm. Magnetic measurements show that the perpendicular anisotropy of the films changes from 3 × 106 to 1.5 × 106 erg/cm3 as the Au thickness changes from 6 to 1 nm. Two films of (Co 0.5 nm/Au 6 nm) × 9/Au 40 nm (denoted Au6) and (Co 0.5 nm/Au 1 nm) × 50/Au 40 nm (denoted Au1) were examined by transmission electron microscopy. For the …

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Interlayer Coupling In Nife/Mo Multilayers And Effect Of Fe Underlayer, M.L. Yan, Z.S. Shan, David J. Sellmyer, W.Y. Lai Apr 1997

Interlayer Coupling In Nife/Mo Multilayers And Effect Of Fe Underlayer, M.L. Yan, Z.S. Shan, David J. Sellmyer, W.Y. Lai

David Sellmyer Publications

We report our studies of exchange coupling in NiFe/Mo multilayers with and without Fe underlayer. The interlayer coupling of NiFe layers across the Mo spacer as well as the magnetic exchange coupling between Fe underlayer and the NiFe/Mo multilayers were observed: The interlayer coupling in NiFe/Mo multilayers exhibits the typical oscillations as a function of the Mo spacer with a period of about 11 Å, and the magnetic exchange coupling between Fe underlayer and the NiFe/Mo multilayers is strongly dependent on the thickness of the Mo spacer tMo and the bilayer number N of NiFe/Mo multilayers. For the [NiFe(20 …

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Magnetic Properties And Switching Volumes Of Nanocrystalline Smfesic Films, S.Y. Zhang, Z.S. Shan, Yi Liu, T.Y. Zhao, J.G. Zhao, B.G. Shen, W.S. Zhan, David J. Sellmyer Apr 1997

Magnetic Properties And Switching Volumes Of Nanocrystalline Smfesic Films, S.Y. Zhang, Z.S. Shan, Yi Liu, T.Y. Zhao, J.G. Zhao, B.G. Shen, W.S. Zhan, David J. Sellmyer

David Sellmyer Publications

Systematic studies of the effects of Si addition on the magnetic and magnetization reversal properties of SmFeSiC films are presented. The magnetic switching volume and other magnetic parameters (e.g., coercivity) are strongly dependent upon the Si content. Correlations between switching volume, coercivity, and the intergrain interactions are discussed.

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Optical And Magneto-Optical Properties Of Mnpt3 Films (Abstract), Kurt W. Wierman, J. N. Hilfiker, Renat F. Sabiryanov, Sitaram Jaswal, Roger D. Kirby, John A. Woollam Apr 1997

Optical And Magneto-Optical Properties Of Mnpt3 Films (Abstract), Kurt W. Wierman, J. N. Hilfiker, Renat F. Sabiryanov, Sitaram Jaswal, Roger D. Kirby, John A. Woollam

Roger Kirby Publications

Optically thick films of MnPt3 were prepared by magnetron sputtering onto quartz substrates. Postdeposition annealing at 850 °C resulted in highly textured (111) films with the L12 (Cu3Au) structure. MnPt3 films are ferromagnetic with a Curie temperature of 380 °C, and they show large magneto-optical effects in the visible. These films also show a high degree of long-range order. The diagonal components of the dielectric tensor were determined using variable angle spectroscopic ellipsometry measurements over the spectral range 1.2–2.4 eV. Magneto-optic Kerr rotation and ellipticity measurements were made at near normal incidence over the …

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Enhanced Temperature Effect On Magnetoresistance In Fe/Mo Multilayers, M.L. Yan, Y.W. Lai, L. Yin, Sy_Hwang Liou Apr 1997

Enhanced Temperature Effect On Magnetoresistance In Fe/Mo Multilayers, M.L. Yan, Y.W. Lai, L. Yin, Sy_Hwang Liou

Sy-Hwang Liou Publications

We have observed an enhancement of the temperature effect on magnetoresistance (MR) in Fe/Mo multilayers with the increase of the Mo layer thickness. MR at the first antiferromagnetic maximum is large and insensitive to the temperature whereas at the third antiferromagnetic maximum it is small and relatively sensitive to the temperature. We found that the mean free path of the conduction electrons increased with the increase of the Mo layer thickness at a fixed temperature and it decreased very slightly with the increase of the temperature at a fixed Mo layer thickness. The interlayer coupling, similar to MR, also has …

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Domain-Wall Curvature And Coercivity In Pinning Type Sm–Co Magnets, Ralph Skomski Apr 1997

Domain-Wall Curvature And Coercivity In Pinning Type Sm–Co Magnets, Ralph Skomski

Ralph Skomski Publications

The origin of coercivity in precipitation hardened Sm–Co magnets is investigated. By considering domain-wall pinning at boundary phase and Z phase inhomogenities, it is found that the hexagonal Z phase has no direct influence on the coercivity. The intuitive assumption of plane domain walls made in a recent calculation is unrealistic but has no direct effect on the coercivity. However, due to the comparatively large size of the 12:17 cells, the calculated three dimensional domain-wall curvature is sufficiently large to assure a nearly ideal nestling of the domain walls to the 1:5 cell boundary. This nestling yields a coercivity increase …

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Magnetism And Morphology Of Fe/Cu(111) Films Below Two-Dimensional Percolation, J. Shen, Ralph Skomski, M. Klaua, H. Jenniches, S. Sundar Manoharan, J. Kirschner Apr 1997

Magnetism And Morphology Of Fe/Cu(111) Films Below Two-Dimensional Percolation, J. Shen, Ralph Skomski, M. Klaua, H. Jenniches, S. Sundar Manoharan, J. Kirschner

Ralph Skomski Publications

The magnetic properties of g-iron films on Cu(111) below the two-dimensional percolation threshold of about 1.4 monolayer are investigated. Iron on flat Cu(111) surfaces forms triangular patches, while it forms stripes along step edges on vicinal surfaces. The films exhibit an easy magnetization axis perpendicular to the film plane and magnetic hysteresis at sufficiently low temperatures. The magnetization curves of the triangular iron patches are discussed in terms of Ising superparamagnetism. From Kerr hysteresis loops, we deduce that the first anisotropy constant K1 in the superparamagnetic films is of order 0.345±0.020 MJ/m3.

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Superparamagnetic Ultrathin Films, Ralph Skomski, D. Sander, J. Shen, J. Kirschner Apr 1997

Superparamagnetic Ultrathin Films, Ralph Skomski, D. Sander, J. Shen, J. Kirschner

Ralph Skomski Publications

The finite-temperature magnetism of ultrathin films such as sesquilayer Fe/W(110) and submonolayer Fe/Cu(111) is investigated. Based on renormalizations of Onsager's exact solution of the two-dimensional Ising model it is shown that superparamagnetism is a common phenomenon in imperfect ultrathin films. The ultimate reason for this behavior is the existence of two structural length scales: the lattice constant, usually considered in renormalization-group theory, and the characteristic size of the film inhomogeneities.

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Magnetic And Structural Properties Of Nd₂Fe₁₇₋ₓmnₓ Solid Solutions, Peter C. Ezekwenna, G. K. Marasinghe, William Joseph James, Oran Allan Pringle, Gary J. Long, H. Luo, Z. Hu, William B. Yelon, Ph. I'Héritier Apr 1997

Magnetic And Structural Properties Of Nd₂Fe₁₇₋ₓmnₓ Solid Solutions, Peter C. Ezekwenna, G. K. Marasinghe, William Joseph James, Oran Allan Pringle, Gary J. Long, H. Luo, Z. Hu, William B. Yelon, Ph. I'Héritier

Chemistry Faculty Research & Creative Works

A series of Nd2Fe17-xMnx solid solutions with x values between 0 and and 6 were prepared and analyzed using magnetic measurements, neutron diffraction, and Mössbauer spectroscopy. All of the Nd2Fe17-xMnx samples crystallized in the Th2Zn17-x-type rhombohedral structure. The lattice parameters and unit cell volumes decrease with increasing manganese content up to ∼ x equal to 2, and then increase for higher manganese content. The magnetizations of Nd2Fe17-xMnx decrease with increasing manganese content and Nd2Fe17-xMnx is paramagnetic …

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Studies Of V, Nb, Cr, And Zr Substituted 2:17 Compounds And Their Carbides Using Neutron Diffraction, H. Luo, Z. Hu, Muguo Chen, William B. Yelon, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, W. C. Chang, S. H. Tsai Apr 1997

Studies Of V, Nb, Cr, And Zr Substituted 2:17 Compounds And Their Carbides Using Neutron Diffraction, H. Luo, Z. Hu, Muguo Chen, William B. Yelon, G. K. Marasinghe, Peter C. Ezekwenna, William Joseph James, W. C. Chang, S. H. Tsai

Physics Faculty Research & Creative Works

Samples of Nd2Fe17-xTxCy with T=V, Nb, Cr, and Zr were prepared by melting of the constituent elements including C and studied by neutron diffraction. Comparing with their uncarbided counterparts, we found that the substituents transfer, more or less, from the 6c site to the 18f and 18h sites with the introduction of C atoms. This behavior appears to relate to the electronegativities between the C atoms and the early transition series elements because the 18f and 18h sites are near neighbors of the interstitial C site. However, the C effects in the V. …

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Accurate Hydrogen Spectral Simulations With A Compact Model Atom, Jason W. Ferguson, Gary J. Ferland Apr 1997

Accurate Hydrogen Spectral Simulations With A Compact Model Atom, Jason W. Ferguson, Gary J. Ferland

Physics and Astronomy Faculty Publications

Many large-scale numerical simulations of astrophysical plasmas must also reproduce the hydrogen ionization and the resulting emission spectrum, in some cases quite accurately. We describe a compact model hydrogen atom that can be readily incorporated into such simulations. It reproduces the recombination efficiency and line spectrum predicted by much larger calculations for a very broad range of densities and temperatures. Uncertainties in hydrogen collision data are the largest source of differences between our compact atom and predictions of more extensive calculations and underscore the need for accurate atomic data.

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Angle-Resolved Study Of Ar 2p₁/₂,₃/₂⁻1Ns,D Resonant Auger Decay, Marc Andrew Humphrey Apr 1997

Angle-Resolved Study Of Ar 2p₁/₂,₃/₂⁻1Ns,D Resonant Auger Decay, Marc Andrew Humphrey

Honors Theses

Angle-resolved measurements of the Ar 2p1/2,3/2-14s,3d,4d and 2p3/2-14s,3d,4d resonant Auger transitions have been carried out using photons from an undulator beamline at the Advanced Light Source of Lawrence Berkeley National Laboratory. The intensity distributions and angular distribution anisotropy (β) parameters have been reported for nearly all of the possible 3p4nl final ionic states. These results further verify the predictions of the spectator model for the 2p1/2,3/2-14s resonances and the subsequent breakdown of this model for the 2p1/2,3/2-13d and 2p1/2,3/2-14d relative intensities. This work …

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The N-15/N-14 Isotope Fractionation In Dissociative Recombination Of N-2(+), Jane L. Fox, Aleksander B. Hać Apr 1997

The N-15/N-14 Isotope Fractionation In Dissociative Recombination Of N-2(+), Jane L. Fox, Aleksander B. Hać

Physics Faculty Publications

We have carried out Monte Carlo calculations of the velocity distributions and escape fractions for 14N and 15N released in dissociative recombination of 28N2+ and 29N2+, respectively, for a range of ion temperatures (Ti) and electron temperatures (Te) appropriate to the Martian exosphere. Separate calculations were carried out for each vibrational level of N2+ for 0≤ν≤6. We have taken into account the variation in the dissociative recombination cross section with relative velocity of the ion and electron, and the differences in the vibrational …

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Evaluation And Application Of Space Telescope Aberration Sensing Using Phase Diversity, David J. Lee Apr 1997

Evaluation And Application Of Space Telescope Aberration Sensing Using Phase Diversity, David J. Lee

Theses and Dissertations

Due to mechanical aspects of fabrication, launch, and operational environment, space telescope optics can suffer from unforeseen aberrations, detracting from their intended diffraction-limited performance goals. This dissertation gives the results of simulation and theoretical studies designed to explore how wavefront aberration information for such "nearly diffraction-limited" telescopes can be estimated via the Gonsalves (least-squares) phase diversity technique. In traditional phase diversity, aberrations are estimated from two images—one conventional, focused image and one image that has been defocused by a known amount. These studies are original and significant in that this effort represents the first time the effects of photon noise …

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Neutron-Irradiation Effects On The V-I Characteristics Of Yba2cu3o7-Δ Twinned Crystals:Linking Transport Results In A Variety Of Copper Oxide Superconductors, Brandon R. Brown Apr 1997

Neutron-Irradiation Effects On The V-I Characteristics Of Yba2cu3o7-Δ Twinned Crystals:Linking Transport Results In A Variety Of Copper Oxide Superconductors, Brandon R. Brown

Physics and Astronomy

We have investigated the depinning process of magnetic flux vortices in twinned crystals of YBa2Cu3O7-δ in intermediate applied magnetic fields parallel to the crystallographic c axis through precise resistivity measurements before and after fast-neutron irradiation. Of particular interest for each field is the power-law dependence of the electric field on current density, E∝Jn, at a well defined temperature which separates a nonlinear region below from a more linear, dissipative region above. We find that n shows a striking dependence on the estimated value of the Larkin-Ovchinnikov length. The relation is not only manifest …

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Structure And Perpendicular Magnetization Of Fe/Ni(111) Bilayers On W(110), D. Sander, Axel Enders, C. Schmidthals, J. Kirschner, H. L. Johnston, C. S. Arnold, David E. Venus Apr 1997

Structure And Perpendicular Magnetization Of Fe/Ni(111) Bilayers On W(110), D. Sander, Axel Enders, C. Schmidthals, J. Kirschner, H. L. Johnston, C. S. Arnold, David E. Venus

Axel Enders Publications

Scanning tunneling microscopy and low energy electron diffraction show that high quality fcc Ni(111) films can be prepared on W(110). The subsequent coverage of this Ni template by monolayers of Fe leads to a Fe/Ni bilayer with striking magnetic properties. The Fe cap layer induces a spin reorientation of the easy axis of magnetization from in-plane to perpendicular to the film, as checked with the magneto-optic Kerr effect. At higher Fe coverages, an in-plane magnetization of the bilayer is found, which is proposed to be caused by the fcc to bcc transition in the Fe layer.

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Optimization Of Plasmas For Recombination-Pumped Short-Wavelength Lasers, Michael James Murphy , '98, Catharine Glasheen , '97, Frank Moscatelli, T. D. Donnelly Apr 1997

Optimization Of Plasmas For Recombination-Pumped Short-Wavelength Lasers, Michael James Murphy , '98, Catharine Glasheen , '97, Frank Moscatelli, T. D. Donnelly

Physics & Astronomy Faculty Works

We report on experiments investigating the optimization of laser-ablated plasmas which are used to produce recombination-pumped, short-wavelength lasers. We evaluate the density of electrons and neutral atoms in laser ablated lithium and carbon plasmas as a function of time and distance away from the ablated target surface. We use an interferometric technique which can reveal information about the temperature of the plasma electrons. We find that the cold electrons which result in gain in recombination-pumped lithium lasers on the Lyman-cr transition are produced by the high-intensity pump pulse rather than the lower intensity ablating pulse.

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Review Of Possible Health Effects Of Exposure To Residential Electric And Magnetic Fields, David W. Hafemeister Apr 1997

Review Of Possible Health Effects Of Exposure To Residential Electric And Magnetic Fields, David W. Hafemeister

Physics

No abstract provided.

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Optimization Of Plasmas For Recombination-Pumped Short-Wavelength Lasers, M. Murphy, C. Glasheen, F. A. Moscatelli, Thomas D. Donnelly Apr 1997

Optimization Of Plasmas For Recombination-Pumped Short-Wavelength Lasers, M. Murphy, C. Glasheen, F. A. Moscatelli, Thomas D. Donnelly

All HMC Faculty Publications and Research

We report on experiments investigating the optimization of laser-ablated plasmas which are used to produce recombination-pumped, short-wavelength lasers. We evaluate the density of electrons and neutral atoms in laser ablated lithium and carbon plasmas as a function of time and distance away from the ablated target surface. We use an interferometric technique which can reveal information about the temperature of the plasma electrons. We find that the cold electrons which result in gain in recombination-pumped lithium lasers on the Lyman-α transition are produced by the high-intensity pump pulse rather than the lower intensity ablating pulse.

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Wind Climatology At 87 Km Above The Rocky Mountains At Bear Lake Observatory--Fabry-Perot Observations Of Oh, V. B. Wickwar, I K. Monson, C M. Vadnais, D Rees Apr 1997

Wind Climatology At 87 Km Above The Rocky Mountains At Bear Lake Observatory--Fabry-Perot Observations Of Oh, V. B. Wickwar, I K. Monson, C M. Vadnais, D Rees

Reports

This paper presents the neutral -wind climatology at approximately 87-km 53 altitude from Utah State University's Bear Lake Observatory (BLO). a mid-latitude site 54 situated in the middle of the Rocky Mountains. The winds were determined using a very 55 sensitive Fabry-Perot interferometer (FPI) observing the OH Me inel (6-2) PI (3) line al 56 843 nm. The climatology. determined from monthly averages of the nightly evolution of 57 the geographic meridional and zonal wind components over forty· five months, has three 58 distinct seasonal patterns: winter (November- February), summer (May-Jul y), and late 59 Slimmer (August and September). The …

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Enhanced Coupling To Microsphere Resonances With Optical Fibers, A. Serpengüzel, S. Arnold, G. Griffel, James A. Lock Apr 1997

Enhanced Coupling To Microsphere Resonances With Optical Fibers, A. Serpengüzel, S. Arnold, G. Griffel, James A. Lock

Physics Faculty Publications

Morphology-dependent resonances (MDR's) of polystyrene microspheres were excited by an optical fiber coupler. For optical elimination of the air-cladding interface at the optical fiber coupler surface, the microsphere was immersed in an index-matching oil. MDR's were observed, even though the relative refractive index between the microsphere and the oil was only 1.09. The observed MDR spectra are in good agreement with the generalized Lorenz-Mie theory and the localization principle. The scattering efficiency into each MDR is estimated as a function of the impact parameter by means of generalized Lorenz-Mie theory. (C) 1997 Optical Society of America.

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Chemistry Of The Jovian Auroral Ionosphere, J. J. Perry, Y. H. Kim, Jane L. Fox, H. S. Porter Apr 1997

Chemistry Of The Jovian Auroral Ionosphere, J. J. Perry, Y. H. Kim, Jane L. Fox, H. S. Porter

Physics Faculty Publications

No abstract provided.

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A Fast Scan Submillimeter Spectroscopic Technique, Douglas T. Petkie, Thomas M. Goyette, Ryan P. A. Bettens, Sergei P. Belov, Sieghard Albert, Paul Helminger, Frank C. De Lucia Apr 1997

A Fast Scan Submillimeter Spectroscopic Technique, Douglas T. Petkie, Thomas M. Goyette, Ryan P. A. Bettens, Sergei P. Belov, Sieghard Albert, Paul Helminger, Frank C. De Lucia

Physics Faculty Publications

A new fast scan submillimeter spectroscopic technique (FASSST) has been developed which uses a voltage tunable backward wave oscillator (BWO) as a primary source of radiation, but which uses fast scan (~105 Doppler limited resolution elements/s) and optical calibration methods rather than the more traditional phase or frequency lock techniques. Among its attributes are (1) absolute frequency calibration to ~1/10 of a Doppler limited gaseous absorption linewidth (<0.1 MHz, 0.000 003 cm-1), (2) high sensitivity, and (3) the ability to measure many thousands of lines/s. Key elements which make this system possible include the excellent short term spectral purity of the …

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Microscopic Nature Of Thermally Stimulated Current And Electrical Compensation In Semi-Insulating Gaas, S. Kuisma, K. Saarinen, P. Hautojarvi, Z-Q. Fang, David C. Look Apr 1997

Microscopic Nature Of Thermally Stimulated Current And Electrical Compensation In Semi-Insulating Gaas, S. Kuisma, K. Saarinen, P. Hautojarvi, Z-Q. Fang, David C. Look

Physics Faculty Publications

No abstract provided.

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