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Electron capture from K shells by fully stripped ions (open access)

Electron capture from K shells by fully stripped ions

This article discusses electron capture from K shells by fully stripped ions.
Date: November 1980
Creator: Lapicki, Gregory & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Object Type: Article
System: The UNT Digital Library
Low-Velocity K-Shell Ionization Cross Sections for Protons, Deuterons and Alpha Particles Bombarding Thin Metal Targets (open access)

Low-Velocity K-Shell Ionization Cross Sections for Protons, Deuterons and Alpha Particles Bombarding Thin Metal Targets

The purpose of this work was to examine the effect of the use the assumption κω2K/ΕCM «1 in calculating K-shell ionization cross sections in the plane wave Born approximation (PWBA) where κω2K is the observed binding energy of the K-shell and ECM is the energy of the incident particle in the center of mass system. Avoiding this assumption produces a threshold for ionization at Ecm = κω2K. Calculations employing the assumption, which leads to the use of approximate limits of integration, do not go to zero for even the .Lowest values of the incident energy.
Date: May 1981
Creator: Rice, Roger Karl
Object Type: Thesis or Dissertation
System: The UNT Digital Library
K-shell ionization by low-velocity ions (open access)

K-shell ionization by low-velocity ions

Article discussing K-shell ionization by low-velocity ions. K-shell x-ray-production measurements are reported for protons, deuterons, and alpha particles incident on thin foils of copper, niobium, silver, and antimony.
Date: August 1981
Creator: Rice, R.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Basbas, George & Duggan, Jerome L.
Object Type: Article
System: The UNT Digital Library
Linewidth Parameters, Dipole Moments, and Microwave Spectrum of Nitrogen-Substituted Methyl Cyanide (open access)

Linewidth Parameters, Dipole Moments, and Microwave Spectrum of Nitrogen-Substituted Methyl Cyanide

The shape of collision-broadened microwave absorption lines is reviewed, along with a number of other broadening mechanisms. The Anderson and Murphy-Boggs linewidth theories are reviewed in detail. Several published modifications to these theories are reviewed. Computer programs which numerically evaluate linewidths and lineshifts are presented. Approximations are made to reduce the need for extensive use of the modified Bessel functions, thereby reducing computation time. Only dipole-dipole forces are considered.
Date: August 1981
Creator: Messer, James Keith
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Photoconductivity Investigation of Two-Photon Magneto-Absorption, PACRH, and Deep Levels in n-InSb (open access)

Photoconductivity Investigation of Two-Photon Magneto-Absorption, PACRH, and Deep Levels in n-InSb

A high resolution photoconductivity investigation of two 13 -3 photon magneto-absorption (TPMA) in n-InSb (n - 9 x 10 cm ) has been performed. This is the first time that two-photon absorption in a semiconductor has been studied with cw lasers only. With a stable cw CC>2 laser and a highly sensitive sampling and magnetic field modulation technique, a minimum of 4 2 transitions in the TPMA photoconductivity spectra can be observed. Most of these transitions are a result of the usual spherical approximation TPMA selections rules (An =0, ±2; As = 0 for e ⊥ B and Δn = 0; Δs = 0 for e || B) . However, some transitions, in particular several near the TPMA band edge, are not explained by these rules. The TPMA spectra have been found to depend upon crystallographic orientation. This has not been previously observed. The temperature variation of the fundamental energy gap Eg between 2 and 100° K is also obtained from TPMA experiments.
Date: May 1982
Creator: Goodwin, Mike Watson
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Rapid isothermal anneal of 75As implanted silicon (open access)

Rapid isothermal anneal of 75As implanted silicon

Article discussing a study of the rapid isothermal anneal of 75As implanted silicon.
Date: September 1, 1982
Creator: Wilson, Scott R.; Gregory, R. B.; Paulson, W. M.; Hamdi, A. H. & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Object Type: Article
System: The UNT Digital Library
Thermal annealing behavior of an oxide layer under silicon (open access)

Thermal annealing behavior of an oxide layer under silicon

This article discusses the thermal annealing behavior of an oxide layer under silicon.
Date: September 27, 1982
Creator: Hamdi, A. H.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Pinizzotto, Russell F.; Matteson, Samuel E.; Lam, H. W. & Malhi, S. D. S.
Object Type: Article
System: The UNT Digital Library
M-shell x-ray production cross sections in thin targets of ₇₉Au, ₈₂Pb, ₈₃Bi, and ₉₂U by 0.3 - 2.6-MeV ₁¹H+ and ₂⁴He+ ions (open access)

M-shell x-ray production cross sections in thin targets of ₇₉Au, ₈₂Pb, ₈₃Bi, and ₉₂U by 0.3 - 2.6-MeV ₁¹H+ and ₂⁴He+ ions

Article discussing M-shell x-ray-production cross sections in thin targets of ₇₉Au, ₈₂Pb, ₈₃Bi, and ₉₂U by 0.3 - 2.6-MeV ₁⁴H+ and ₂⁴He+ ions.
Date: October 1982
Creator: Mehta, R.; Duggan, Jerome L.; Price, J. L.; McDaniel, Floyd Del. (Floyd Delbert), 1942- & Lapicki, Gregory
Object Type: Article
System: The UNT Digital Library
Infrared-Microwave Double Resonance Probing of the Population-Depopulation of Rotational States in the NO₂ and the SO₂ Molecules (open access)

Infrared-Microwave Double Resonance Probing of the Population-Depopulation of Rotational States in the NO₂ and the SO₂ Molecules

A 10.6 ym C02 laser operating a power range S P 200 watts was used to pump some select vibrational transitions in the NO2 molecule while monitoring the rotational transitions (91/9—'100/10), (232f 22 ~~"*242,23> ' (402,38 "393,37) in the (0, 0, 0) vibrational level and the (8q,8—*"^1,7) rotational transition in the (0, 1, 0) vibrational level. These rotational transitions were monitored by microwave probing to determine how the population of states in the rotational manifolds were being altered by the laser. Coincidences between some components of the V3-V2 band of N02 and the C02 infrared laser lines in the 10 um region appeared to be responsible for the strong interaction between the continuous laser beams and the molecular states.
Date: December 1982
Creator: Khoobehi, Bahram
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Picosecond Laser-Induced Transient Gratings and Anisotropic State-Filling in Germanium (open access)

Picosecond Laser-Induced Transient Gratings and Anisotropic State-Filling in Germanium

We present a comparative theoretical study of the transient grating coherent effects in resonant picosecond excitation-probe experiments. Signals in both the probe and conjugate directions are discussed. The effects of recombination, non-radiative scattering and spatial and orientational diffusion are included. The analysis is applied to both a molecular and to a semiconductor model. Signal contributions from concentration and orientational gratings are distinguished and their temporal natures discussed. The theory is used to explain our recent observations in germanium. Included are discussions of picosecond transient grating self-diffraction measurements that can be understood in terms of an orientational grating produced by anisotropic (in k-space) state-filling. Though there have been predictions and indirect experimental evidence for isotropic state-filling in germanium, this is the first direct experimental indication of anisotropic state-filling in a semiconductor.
Date: December 1982
Creator: Boggess, Thomas F. (Thomas Frederick)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Direct ionization and electron capture in M-shell x-ray production by fluorine ions (open access)

Direct ionization and electron capture in M-shell x-ray production by fluorine ions

This article discusses direct ionization and electron capture in M-shell x-ray production by fluorine ions.
Date: November 1983
Creator: Mehta, R.; Duggan, Jerome L.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Andrews, M. C.; Lapicki, Gregory; Miller, P. D. et al.
Object Type: Article
System: The UNT Digital Library
₁¹H+ - and ₂⁴He+ - induced M-shell x-ray-production cross sections for selected elements in the rare-earth region (open access)

₁¹H+ - and ₂⁴He+ - induced M-shell x-ray-production cross sections for selected elements in the rare-earth region

Article on ₁¹H+ and ₂⁴He+ -induced M-shell x-ray-production cross sections for selected elements in the rare-earth region.
Date: December 1983
Creator: Mehta, R.; Duggan, Jerome L.; Price, J. L.; Kocur, P. M.; McDaniel, Floyd Del. (Floyd Delbert), 1942- & Lapicki, Gregory
Object Type: Article
System: The UNT Digital Library
A Gauge-Invariant Energy Variational Principle Application to Anisotropic Excitons in High Magnetic Fields (open access)

A Gauge-Invariant Energy Variational Principle Application to Anisotropic Excitons in High Magnetic Fields

A new method is developed for treating atoms and molecules in a magnetic field in a gauge-invariant way using the Rayleigh-Ritz energy variational principle. The energy operator depends on the vector potential which must be chosen in some gauge. In order to adapt the trial wave function to the gauge of the vector potential, the trial wave function can be multiplied by a phase factor which depends on the spatial coordinates. When the energy expectation value is minimized with respect to the phase function, the equation for charge conservation for stationary states is obtained. This equation can be solved for the phase function, and the solution used in the energy expectation value to obtain a gauge-invariant energy. The method is applicable to all quantum mechanical systems for which the variational principle can be applied. It ensures satisfaction of the charge conservation condition, a gauge-invariant energy, and the best upper bound to the ground-state energy which can be obtained for the form of trial wave function chosen.
Date: December 1983
Creator: Kennedy, Paul K. (Paul Kevin)
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Fast diffusion of As in polycrystalline silicon during rapid thermal annealing (open access)

Fast diffusion of As in polycrystalline silicon during rapid thermal annealing

This article discusses fast diffusion of As in polycrystalline silicon during rapid thermal annealing.
Date: May 30, 1984
Creator: Wilson, Scott R.; Paulson, W. M.; Gregory, R. B.; Gressett, J. D.; Hamdi, A. H. & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Object Type: Article
System: The UNT Digital Library
Rapid isothermal annealing of As-, P-, and B-implanted silicon (open access)

Rapid isothermal annealing of As-, P-, and B-implanted silicon

This article discusses rapid idothermal annealing of As-, P-, and B-implanted silicon.
Date: June 15, 1984
Creator: Wilson, Scott R.; Paulson, W. M.; Gregory, R. B.; Hamdi, A. H. & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Object Type: Article
System: The UNT Digital Library
Picosecond Measurement of Interband Saturation, Intervalence Band Absorption, and Surface Recombination in Germanium (open access)

Picosecond Measurement of Interband Saturation, Intervalence Band Absorption, and Surface Recombination in Germanium

The picosecond optical response of five thin germanium samples was measured following intense optical excitation using two variations of the excitation and probe technique. Seven-picosecond laser pulses of wavelength 1.054 um were used to measure the optical transmission of the samples for a variety of probe delays, excitation fluences, and sample temperatures. These parametric experiments were performed in an effort to determine if carrier cooling, carrier diffusion, or carrier recombination dominates the carrier dynamics immediately following excitation. The studies of a 5.7 um thick sample indicated that Auger recombination does not dominate the carrier dynamics, but that the carriers most likely cool immediately to within a few optical phonons of the lattice temperature. Lattice heating may also occur depending on excitation level. Neither cooling nor diffusion was ruled out as a major contributor to the transient optical response. A numerical analysis indicated that, although diffusion may be minimized in the thinner samples, the importance of surface recombination increases as the sample thickness decreases. The lattice temperature dependence of the optical transmission was found not to be in disagreement with the known temperature dependence of the low-density diffusion coefficient. Finally, new structure was observed in the data which is consistent with …
Date: August 1984
Creator: Perryman, Gary Paul
Object Type: Thesis or Dissertation
System: The UNT Digital Library
L-shell x-ray production cross sections of Ni, Cu, Ge, As, Rb, Sr, Y, Zr, and Pd by (0.25-2.5)-MeV protons (open access)

L-shell x-ray production cross sections of Ni, Cu, Ge, As, Rb, Sr, Y, Zr, and Pd by (0.25-2.5)-MeV protons

Article discussing L-shell x-ray production cross sections of Ni, Cu, Ge, As, Rb, Sr, Y, Zr, and Pd by (0.25-2.5)-MeV protons.
Date: October 1985
Creator: Duggan, Jerome L.; Kocur, P. M.; Price, J. L.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Mehta, R. & Lapicki, Gregory
Object Type: Article
System: The UNT Digital Library
K-shell x-ray production by 0.5-2.5-MeV ₄⁹Be+ ions incident upon selected elements from fluorine to potassium (open access)

K-shell x-ray production by 0.5-2.5-MeV ₄⁹Be+ ions incident upon selected elements from fluorine to potassium

Article discussing K-shell x-ray production by 0.5-2.5-MeV ₄⁹Be+ ions incident upon selected elements from fluorine to potassium.
Date: October 1986
Creator: Price, J. L.; Duggan, Jerome L.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Lapicki, Gregory & Mehta, R.
Object Type: Article
System: The UNT Digital Library
Multiple outer-shell ionization effect in inner-shell x-ray production by light ions (open access)

Multiple outer-shell ionization effect in inner-shell x-ray production by light ions

This article discusses multiple outer-shell ionization effect in inner-shell x-ray production by light ions.
Date: November 1986
Creator: Lapicki, Gregory; Mehta, R.; Duggan, Jerome L.; Kocur, P. M.; Price, J. L. & McDaniel, Floyd Del. (Floyd Delbert), 1942-
Object Type: Article
System: The UNT Digital Library
Carbon K-shell x-ray and Auger-electron production in hydrocarbons and carbon oxides by 0.6-2.0-MeV protons (open access)

Carbon K-shell x-ray and Auger-electron production in hydrocarbons and carbon oxides by 0.6-2.0-MeV protons

Article discussing research on carbon K-shell x-ray and Auger-electron production in hydrocarbons and carbon oxides by 0.6-2.0-MeV protons.
Date: May 1, 1987
Creator: Bhalla, R. P.; McDaniel, Floyd Del. (Floyd Delbert), 1942- & Lapicki, Gregory
Object Type: Article
System: The UNT Digital Library
L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions (open access)

L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions

Article discussing research on L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions.
Date: October 15, 1987
Creator: Andrews, M. C.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Duggan, Jerome L.; Miller, P. D.; Pepmiller, P. L.; Krause, H. F. et al.
Object Type: Article
System: The UNT Digital Library
M-shell x-ray production cross sections for 0.5-2.5-MeV Be+ ions incident upon selected elements from praseodymium to bismuth (open access)

M-shell x-ray production cross sections for 0.5-2.5-MeV Be+ ions incident upon selected elements from praseodymium to bismuth

This article discusses M-shell x-ray production cross sections for 0.5-2.5-MeV Be+ ions incident upon selected elements from praseodymium to bismuth.
Date: January 15, 1988
Creator: Price, J. L.; Duggan, Jerome L.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Lapicki, Gregory & Mehta, R.
Object Type: Article
System: The UNT Digital Library