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Franck Condon Factors And R-Centeroids For Six Diatomic Molecules, Patricia M. Fazio May 1979

Franck Condon Factors And R-Centeroids For Six Diatomic Molecules, Patricia M. Fazio

Physics Theses & Dissertations

The Franck Condon factor is defined as the square of the overlap integral and is so named because of its ties with the Franck Condon Principle. The r-centroid is the internuclear separation associated with the electronic transition of the diatomic molecule. The physical meaning of these integrals is discussed. Two methods for construction of the wavefunctions are presented. Both methods employ the Morse Potential Energy function. The first method calculates the integrals using the analytic wavefunction of Morse and the second method has numerically constructed wavefunct!ons. The twelve transitions and six diatomic molecules studied include; B 2Σ+ to X …

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The Effects Of Proton Irradiation On The Absorption Of Multi Component Glasses, Marcia Frances Bartusiak Apr 1979

The Effects Of Proton Irradiation On The Absorption Of Multi Component Glasses, Marcia Frances Bartusiak

Physics Theses & Dissertations

Three Schott glasses typically used in space technology -­ LaK 21, KzFS N4, and LF 5 -- were irradiated with 85 MeV protons. Induced absorption spectra were determined for each glass after varying fluences of radiation. It was found that the spectra for each glass can be fitted with three Gaussian shaped bands in the near ultraviolet-visible region, while a fourth Gaussian characterizes the absorption edge. For doses up to 107 rads, the dependence of the induced absorption a on total dose is accurately described by the saturating exponential function a(Φ)= as (1 - e--b Φ ) …

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Effect Of Critical Slowdown On Nuclear Magnetic Resonance In Solids Near A Second-Order Structural Transition, Rolfe G. Petschek Mar 1979

Effect Of Critical Slowdown On Nuclear Magnetic Resonance In Solids Near A Second-Order Structural Transition, Rolfe G. Petschek

Faculty Scholarship

We have analyzed the critical behavior of nuclear spin-relaxation rates in several cases, where the relaxation rate remains finite but its temperature derivative is expected to diverge at Tc. We find that the temperature derivative of the relaxation rate contains two divergent terms, one which behaves like the specific heat, and one whose divergence is given by naive dynamic scaling arguments and depends on the form of the coupling terms of the order parameter.

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Mechanism Of ¹⁴N(T,P) To The Ground State Quadruplet In ¹⁶N, H. T. Fortune, Oleksa-Myron Bilaniuk, G. Stephans, R. Middleton Jan 1979

Mechanism Of ¹⁴N(T,P) To The Ground State Quadruplet In ¹⁶N, H. T. Fortune, Oleksa-Myron Bilaniuk, G. Stephans, R. Middleton

Physics & Astronomy Faculty Works

Complete angular distributions (8°-168°) have been measured for the ¹⁴N(t,p)¹⁶N reaction, at a bombarding energy of 15 MeV, leading to the lowest four levels of ¹⁶N. Results have been analyzed using distorted-wave Born approximation and microscopic wave functions. The approximate magnitude of the compound-nucleus component has been extracted. NUCLEAR REACTION ¹⁴N(t,p), E=15 MeV; ¹⁶N levels, deduced reaction mechanism and tested shell-model wave functions. DWBA analysis.

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Effect Of Displaced Geomagnetic And Geographic Poles On High-Latitude Plasma Convection And Ionospheric Depletions, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk Jan 1979

Effect Of Displaced Geomagnetic And Geographic Poles On High-Latitude Plasma Convection And Ionospheric Depletions, Jan Josef Sojka, W. J. Raitt, Robert W. Schunk

All Physics Faculty Publications

We assumed that the ionospheric plasma at high latitudes has a tendency to corotate about the geographic pole and that magnetospheric convection is relative to the geomagnetic pole. With this assumption we calculated plasma drift patterns over the polar cap for a range of constant magnetospheric electric fields as well as for asymmetric electric fields with enhanced plasma flow on either the dawnside or the duskside of the polar cap. We calculated the drift patterns in both the geographic inertial and the geomagnetic inertial frame taking into account the displacement between the geographic and geomagnetic poles. We found that this …

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Electronic Structure Calculation Of Icosahedral B-12, R. P. Wagner, Gust Bambakidis Jan 1979

Electronic Structure Calculation Of Icosahedral B-12, R. P. Wagner, Gust Bambakidis

Physics Faculty Publications

No abstract provided.

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Distortion Isomerism In Ferrous Thiourea Complexes - Ii(1) Thermodynamics And Kinetics, R. Latorre, J. A. Costamagna, E. Frank, C. R. Abeledo, R. B. Frankel Jan 1979

Distortion Isomerism In Ferrous Thiourea Complexes - Ii(1) Thermodynamics And Kinetics, R. Latorre, J. A. Costamagna, E. Frank, C. R. Abeledo, R. B. Frankel

Physics

Mössbauer spectroscopy as a function of temperature of Fe(II)(N,N′-dicyclohexyl-thiourea)6(ClO4)2(FeDCTU) shows the existence of two isomeric forms A and B which coexist in the temperature range 200 < T < 300 K. The relative concentrations of A and B were studied as a function of time at different temperatures in the coexistence region. From the equilibrium constant as a function of temperature we obtain the following thermodynamic parameters: ΔH = −4520 ± 120 cal/mol and δS = 20 ± 0.1 e.u. The kinetics seem to follow an ordinary first order law but with an unusual temperature dependence of the rate constant k1. The results are discussed in terms of hydrogen bonded interactions between the perchlorate anions and the cyclohexylthiourea moieties.

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Precision Doubly Differential Cross Section Measurements, John T. Park Jan 1979

Precision Doubly Differential Cross Section Measurements, John T. Park

Physics Faculty Research & Creative Works

Ion Energy Loss Spectrometry has been applied to the measurement of cross sections differential in both scattering angle and ion energy loss. Differential cross sections obtained for excitation of the n=2 level of atomic hydrogen by various ions provides unexpectedly good agreement with the available theories. Copyright © 1978 by The Institute of Electrical and Electronics Engineers, Inc.

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Temperature Dependence Of The Electron Attachment Coefficient In Iodine, Howard L. Brooks, Scott R. Hunter, Kaare J. Nygaard Jan 1979

Temperature Dependence Of The Electron Attachment Coefficient In Iodine, Howard L. Brooks, Scott R. Hunter, Kaare J. Nygaard

Physics Faculty Research & Creative Works

The attachment coefficient for iodine in a (1% I2+99% N 2) mixture, 50 Torr total pressure, has been measured in an electron swarm experiment from 1 to 50 Townsends (1 Townsend=1Td=10-17 V cm2). As the temperature was increased from 35 to 110°C, the attachment coefficient increased for any E/N (electric field intensity/gas number density) values greater than 7 Td. These results are compared to other experimental data and an explanation for the temperature dependence, based on the population of upper vibrational states, is presented. © 1979 American Institute of Physics.

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Negative Ion Production Rates In Rare Gas-Halide Lasers, Kaare J. Nygaard, Howard L. Brooks, Scott R. Hunter Jan 1979

Negative Ion Production Rates In Rare Gas-Halide Lasers, Kaare J. Nygaard, Howard L. Brooks, Scott R. Hunter

Physics Faculty Research & Creative Works

This paper reports on dissociative electron attachment in F2, NF3, Cl2, and I2. The principle of the method is to produce a short burst of photoelectrons from a photocathode by means of light from an argon-fluoride laser. Subsequently, by studying the motion of electrons and negative ions in a constant electric field (E) region, information is obtained about drift velocities and effective attachment cross sections. Helium, argon, and nitrogen were used as buffer gases. Of particular interest is a very strong temperature dependence of the attachment coefficient in I2. Measurements were taken from 35 to 110°C, covering an E/N range …

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Cndo Calculations On The Structure Of A Liquid Sodium Carboxylate-Carboxylic Acid Compound, Beverly Bendiksen, Stig Friberg, Patricia L.M. Plummer Jan 1979

Cndo Calculations On The Structure Of A Liquid Sodium Carboxylate-Carboxylic Acid Compound, Beverly Bendiksen, Stig Friberg, Patricia L.M. Plummer

Chemistry Faculty Research & Creative Works

The molecular interactions in a carboxylic acid/sodium carboxylate compound which is a liquid at room temperature were calculated using a CNDO/2 approach. The calculations gave results distinguishing the energy for different conformations in the molecular compound. The maximum binding energy was found for a structure in which the four acids were bridging with a hydrogen bond from the acid OH group to the carboxylate group and the acid carbonyl groups forming a ligand bond to the carboxylate sodium ion. © 1979 Academic Press, Inc.

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Negative Ion Charge Transfer Of The Reaction Of S⁻ And O⁻ With Atomic Hydrogen Producing H⁻ Ions From 1500 To 10 Kev, George F. Hagner Jan 1979

Negative Ion Charge Transfer Of The Reaction Of S⁻ And O⁻ With Atomic Hydrogen Producing H⁻ Ions From 1500 To 10 Kev, George F. Hagner

Doctoral Dissertations

"The charge transfer reactions of 0-, S- with atomic hydrogen were studied from 1.5 to 10 KeV, and the reaction Cl- + O2 + O2- + Cl was studied from 10 eV to 10 KeV. The reactions studied were normalized to the reaction H- + H + H + H-. The maximum measured cross sections were 4.6 x 10-16 cm2 for the reaction Cl- + O2 + O2- + Cl and 4.4 x 10-15 cm2 for the reaction 0- + H …

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Perturbation Theory In A Strong-Interaction Regime With Application To 4d-Subshell Spectra Of Ba And La, Göran Wendin, Anthony F. Starace Dec 1978

Perturbation Theory In A Strong-Interaction Regime With Application To 4d-Subshell Spectra Of Ba And La, Göran Wendin, Anthony F. Starace

Anthony F. Starace Publications

We investigate the behavior of a bound electron–hole excitation in an energy region where the response of the system is highly resonant and shows strong collective behavior. Formulae for calculating discrete energy levels and wavefunctions are presented for the case where the perturbation is strong enough to change the nodal structure of the perturbed wavefunctions relative to that of the unperturbed wavefunctions. This change in nodal structure requires a renaming of the associated atomic states. Neglect of such renaming is shown to have been at the root of a recent controversy between differing interpretations, based on alternative calculational procedures, of …

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Role Of Low-Energy Two-Body Virtual States In Three-Particle Scattering Situations, James A. Lock Dec 1978

Role Of Low-Energy Two-Body Virtual States In Three-Particle Scattering Situations, James A. Lock

Physics Faculty Publications

A model three-particle scattering situation consisting of a projectile incident on a target bound to a residual core was considered under the assumptions that there was a low-energy virtual state in the projectile-target channel, that the projectile and core did not interact, and that the projectile-target and target-core interactions were s-wave separable interactions. When the appropriate Faddeev equations were solved by inversion, an enhancement was found in the three-body elastic cross section for virtual state energies less than or comparable to the target-core binding energy. This enhancement was determined to be kinematical in origin.

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Electron Attachment In Dilute Fluorine-Helium Mixtures, Kaare J. Nygaard, Scott R. Hunter, John L. Fletcher, Stephen R. Foltyn Dec 1978

Electron Attachment In Dilute Fluorine-Helium Mixtures, Kaare J. Nygaard, Scott R. Hunter, John L. Fletcher, Stephen R. Foltyn

Physics Faculty Research & Creative Works

We have made an absolute determination of the electron attachment coefficient η (cm-1) in helium containing 0.1-1% fluorine covering an E/N range from 3Td-17Td. At an estimated average energy of 5 eV we find a rate coefficient equal to (7.5±1.5) x10-10 cm3/sec.

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Principal Angle, Principal Azimuth, And Principal-Angle Ellipsometry Of Film-Substrate Systems, R. M.A. Azzam, A.-R. M. Zaghloul Dec 1978

Principal Angle, Principal Azimuth, And Principal-Angle Ellipsometry Of Film-Substrate Systems, R. M.A. Azzam, A.-R. M. Zaghloul

Electrical Engineering Faculty Publications

When the film thickness is considered as a parameter, a system composed of a transparent film on an absorbing substrate (in a transparent ambient) is characterized by a range of principal angle ø¯min ≤ ø¯ ≤ ø¯max over which the associated principal azimuth ψ¯ varies between 0° and 90° (i.e., 0° ≤ ψ¯ ≤ 90°) and the reflection phase difference Δ assumes either one of the two values: +π/2 or −π/2. We determine the principal angle ø¯(d) and principal azimuth ψ¯(d) as functions of film thickness d for the vacuum-SiO2-Si system at …

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Propagation Of Partially Polarized Light Through Anisotropic Media With Or Without Depolarization: A Differential 4 × 4 Matrix Calculus, R. M.A. Azzam Dec 1978

Propagation Of Partially Polarized Light Through Anisotropic Media With Or Without Depolarization: A Differential 4 × 4 Matrix Calculus, R. M.A. Azzam

Electrical Engineering Faculty Publications

We extend the scope of the Mueller calculus to parallel that established by Jones for his calculus. We find that the Stokes vector S of a light beam that propagates through a linear depolarizing anisotropic medium obeys the first-order linear differential equation dS/dz = mS, where z is the distance traveled along the direction of propagation and m is a 4 × 4 real matrix that summarizes the optical properties of the medium which influence the Stokes vector. We determine the differential matrix m for eight basic types of optical behavior, find its form for the most general anisotropic nondepolarizing …

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Two-Nucleon Transfer To T-Mixed States In ¹⁶O, H. T. Fortune, R. Middleton, Oleksa-Myron Bilaniuk Oct 1978

Two-Nucleon Transfer To T-Mixed States In ¹⁶O, H. T. Fortune, R. Middleton, Oleksa-Myron Bilaniuk

Physics & Astronomy Faculty Works

In a comparison of the reactions ¹⁴N(t, p) to the g.s. quadruplet of ¹⁶N and ¹⁴N(³He, p) to the dominantly T=1 analogs in ¹⁶O, only the 2⁻ levels have the expected cross-section ratio: σ(³He, p) over σ(t, p)=0.5. The cross sections for O⁻ and 3⁻ levels of 16O are reduced by a further factor of 2. Direct-reaction calculations are unable to reproduce the results. NUCLEAR REACTIONS ¹⁴N(t, p), ¹⁴N(³He, p), E=15.0 MeV; measured σ(Eₚ, θ). T mixing effect on reaction mechanism.

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High Let Constraints On Low Let Survival, Robert Katz Sep 1978

High Let Constraints On Low Let Survival, Robert Katz

Robert Katz Publications

Survival curves for biological cells irradiated with gamma rays (and other low LET radiations) cannot be properly interpreted without examining the implications of these interpretations for high LET radiations. The theory of RBE demands that the RBE of any high LET radiation field is at most one when the probability for cell killing as a function of the absorbed dose of gamma rays is linear or sublinear, for homogeneous samples whose radiosensitivity parameters are not altered during the irradiation. A contrary experimental finding strongly suggests that the experimental sample is heterogeneous. Violation of this constraint is not unusual where the …

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20th Annual Rocky Mountain Conference On Analytical Chemistry Aug 1978

20th Annual Rocky Mountain Conference On Analytical Chemistry

Rocky Mountain Conference on Magnetic Resonance

Abstracts and program from the 20th annual meeting of the Rocky Mountain Conference on Analytical Chemistry, 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 7-9, 1978.

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Esr And Spin-Lattice Relaxation Of Nd3+ In A Metallic Host: Larh2, S. A, Dodds, Jeff Sanny, R. Orbach Aug 1978

Esr And Spin-Lattice Relaxation Of Nd3+ In A Metallic Host: Larh2, S. A, Dodds, Jeff Sanny, R. Orbach

Physics Faculty Works

We report the first ESR observation of Nd3+ in a metal: cubic LaRh2. The resonance arises from a Γ6 ground state and exhibits hyperfine splitting at low temperature, allowing for positive identification. Above about 12 K, the ESR linewidth increases exponentially with temperature. We attribute this increase to the resonance phonon relaxation process involving the first excited state at 125±10 K.

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Angular Differential Cross Sections For 25-, 50-, And 100-Kev-Proton Excitation Of Helium To The N=2 Level, John T. Park, Jacob M. George, Jerry Peacher, John E. Aldag Jul 1978

Angular Differential Cross Sections For 25-, 50-, And 100-Kev-Proton Excitation Of Helium To The N=2 Level, John T. Park, Jacob M. George, Jerry Peacher, John E. Aldag

Physics Faculty Research & Creative Works

Differential cross sections for 25-, 50-, and 100-keV-proton excitation of helium to the n=2 level have been determined for center-of-mass scattering angles from 0 to 1.2 mrad. The cross sections were obtained from an analysis of the angular distribution of the scattered protons which had lost an energy corresponding to the excitation of the helium target to its n=2 level. The differential cross section is very sharply peaked in the forward direction and decreases by a factor of 45 in 1.0 mrad at 25 keV and by a factor of 650 in 1.0 mrad at 100 keV. The data are …

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Infrared Spectral Detectivity Of Cr‐Doped Gaas, David C. Look Jun 1978

Infrared Spectral Detectivity Of Cr‐Doped Gaas, David C. Look

Physics Faculty Publications

The room‐temperature spectral detectivity of Cr‐doped GaAs has been examined in the impurity excitation region out to 1.7 μ, a range which includes the wavelengths of several important lasers as well as low‐loss optical fibers. The results include values of D∗ greater than 1011 cm Hz1/2/W in the photoconductive mode, and 1010 cm Hz1/2/W in the photomagnetoelectric mode. Small carrier lifetimes, ∼10−8 sec, offer the potential of high‐speed operation; however, the measured response times are much larger, ∼10−3–10−2 sec, because of very high input impedances. Formulas are presented to …

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Magnetic Properties Of Linear Chain Systems: Metamagnetism Of Single Crystal Co(Pyridine)2Cl2, S. Foner, Richard B. Frankel, W. M. Reiff, H. Wong, Gary J. Long Jun 1978

Magnetic Properties Of Linear Chain Systems: Metamagnetism Of Single Crystal Co(Pyridine)2Cl2, S. Foner, Richard B. Frankel, W. M. Reiff, H. Wong, Gary J. Long

Physics

The metamagnetic behavior of the low temperature properties of single crystal Co(pyridine)2Cl2 is discussed. At 1.25 K oriented single crystals exhibit a two‐step metamagnetic transition at applied fields ∼0.8 and 1.6 kG along the b‐axis, a single transition at ∼0.7 kG for applied fields along the a∗ axis, and a single transition at ∼4.2 kG for an applied field along the c axis. Just above the transition fields a moment of 2μB/Co atom is measured for B0 parallel to the a∗ axis or b axis, and 0.4μB/Co atom is …

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Calculated Yields And Slowing-Down Spectra For Electrons In Liquid Water: Implications For Electron And Photon Rbe, R. N. Hamm, H. A. Wright, Robert Katz, J. E. Turner, R. H. Ritchie Jun 1978

Calculated Yields And Slowing-Down Spectra For Electrons In Liquid Water: Implications For Electron And Photon Rbe, R. N. Hamm, H. A. Wright, Robert Katz, J. E. Turner, R. H. Ritchie

Robert Katz Publications

Detailed Monte Carlo calculations have been carried out of slowing-down spectra and yields for a number of end-points for electrons in liquid water. These investigations were made to study differences in physical effects of different low-LET radiations and implications for RBE. Initial electron energies from 1 keV to 1 MeV were used, and all secondary electrons were followed in the computations until their energies fell below 10 eV. Though there are substantial differences in the slowing-down spectra at energies near and above the K-shell ionization potential of oxygen, the energy spectrum of electrons at lower energies is found to be …

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Electron Drift Velocities In Helium-Fluorine Gas Mixtures, Kaare J. Nygaard, John L. Fletcher, Scott R. Hunter, Stephen R. Foltyn May 1978

Electron Drift Velocities In Helium-Fluorine Gas Mixtures, Kaare J. Nygaard, John L. Fletcher, Scott R. Hunter, Stephen R. Foltyn

Physics Faculty Research & Creative Works

Using a simple time-of-flight technique, we have measured the electron drift velocity in helium with 0.1-1% fluorine additive. Our results in a 0.1% mixture are in close agreement with data in pure helium. The measured drift velocity increases with increasing fluorine concentration. © 1978, American Institute of Physics. All rights reserved.

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Isospin Forbidden And Allowed Reactions 16O(Α,Α0)160 And 160(Α,Γ)20Ne, Daniel J. Steck Mar 1978

Isospin Forbidden And Allowed Reactions 16O(Α,Α0)160 And 160(Α,Γ)20Ne, Daniel J. Steck

Physics Faculty Publications

Six 20Ne levels have been investigated in detail via the 16O+α channel between 6.9≤Eα≤10.2 MeV. Level parameters for states at Ex(20Ne)=10.264±0.008, 11.077±0.008, 11.259±0.008, 11.552±0.008,12.237±0.008, and 12.390±0.008 MeV have been extracted from γ decay properties and phase shift analysis of the elastic scattering. With the exception of the 11.552 and 12.39 MeV states, these levels display primarily TT=0 states, several other weak γ decaying resonances were observed at 11.97 ± 0.04, 12.05 ± 0.04, and 12.49 ± 0.02 MeV but were not studied in detail. Charge dependent matrix elements (4-120 …

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Evolved Contact Systems Of Spectral Type A: Au Puppis, V535 Arae, And V1073 Cygni, Kam-Ching Leung, Donald P. Schneider Jan 1978

Evolved Contact Systems Of Spectral Type A: Au Puppis, V535 Arae, And V1073 Cygni, Kam-Ching Leung, Donald P. Schneider

Department of Physics and Astronomy: Faculty Publications

The photoelectric observations of AU Pup, V535 Ara, and V1073 Cyg were reanalyzed with Wilson and Devinney's approach. All three systems are found to be contact configurations. AU Pup has an unusually large degree of overcontact, 72%. V1073 Cyg is found to be an evolved contact system since the radius of the primary is twice that of a zero-age main-sequence star of corresponding mass. All three systems are found to be evolved according to their locations in the period-spectral-type diagram. Improved photometric parameters are reported for all three systems.

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Plasma Lines In The Auroral E Layer, Vincent B. Wickwar Jan 1978

Plasma Lines In The Auroral E Layer, Vincent B. Wickwar

All Physics Faculty Publications

The first successful measurements of plasma lines in the auroral E layer were made in January 1976 using the Chatanika incoherent scatter radar. Although they are considerably weaker than the signal from the ion component, the plasma line signals are readily detectable. Typical signal-to-noise ratios were about 4%. In this series of experiments, plasma lines were observed in the interval between 3.8 and 6.0 MHz, which corresponds to phase energies between 0.55 and 1.4 eV. They were found between 98 and 134 km; the derived plasma wave intensities varied between 0.06 and 1.0 eV, and the enhancements between 4 and …

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Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. Ii. 100-500-Ev Electrons On Neon, Argon, Molecular Hydrogen, And Molecular Nitrogen, R. D. Dubois, M. Eugene Rudd Jan 1978

Absolute Doubly Differential Cross Sections For Ejection Of Secondary Electrons From Gases By Electron Impact. Ii. 100-500-Ev Electrons On Neon, Argon, Molecular Hydrogen, And Molecular Nitrogen, R. D. Dubois, M. Eugene Rudd

M. Eugene Rudd Publications

Absolute doubly differential cross sections for secondary electron production by electron impact have been measured for static gas targets of neon, argon, hydrogen, and nitrogen. Electron impact energies were from 100 to 500 eV. An electrostatic analyzer was used to analyze secondary electrons with energies between 4 eV and the primary electron energy minus the first ionization potential of the target. Angles of emission were 10° to 150°. The present data agree well with the data of Opal, Beaty, and Peterson at 90° but, as was observed previously for helium, the agreement becomes increasingly poorer for larger and smaller angles. …

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