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Full-Text Articles in Physical Sciences and Mathematics
Electron Detachment For H-(D-) In Collisions With Ne, T. S. Wang, John B. Delos
Electron Detachment For H-(D-) In Collisions With Ne, T. S. Wang, John B. Delos
Arts & Sciences Articles
Total cross sections for electron detachment in collisions of H− and D− with Ne are calculated, using a model based on a first‐order solution to close‐coupled equations. Quantities needed for the calculation are the energy gap and the coupling between bound and free states. The energy gap is taken from previous calculations and the coupling is assumed to be of exponential form, with parameters adjusted to fit experimental data. Special examination is made of isotope effects in the cross sections.
Highly Excited States Of A Hydrogen Atom In A Strong Magnetic Field, John B. Delos, Stephen Knudson, D. W. Knudson
Highly Excited States Of A Hydrogen Atom In A Strong Magnetic Field, John B. Delos, Stephen Knudson, D. W. Knudson
Arts & Sciences Articles
Classical trajectories and semiclassical energy eigenvalues are calculated for an atomic electron in a high Rydberg state in an external magnetic field. With the use of perturbation theory, a classical trajectory is described as a Kepler ellipse with orbital parameters evolving slowly with time. As they evolve, the ellipse rocks, tilts, and flips in space, but the length of its major axis remains approximately constant. Exact numerical calculations verify that perturbation theory is quite accurate for the cases considered (principal quantum number ≃ 30, magnetic field ≲ 6 T). Action variables are calculated from perturbation theory and from exact trajectories, …
Quantum Theory Of Slow Atomic Collisions, John B. Delos
Quantum Theory Of Slow Atomic Collisions, John B. Delos
Arts & Sciences Articles
Quantum-mechanical and semiclassical theories of slow atomic collisions are reviewed, with attention to electron-translation factors and their effects.
A General Theory Of Electron Detachment In Negative Ion Collisions, Tzuu-Shin Wang
A General Theory Of Electron Detachment In Negative Ion Collisions, Tzuu-Shin Wang
Dissertations, Theses, and Masters Projects
In this thesis a general theory of electron detachment in slow collisions of negative ions with atoms is presented. The theory is based upon a semiclassical close-coupling framework, following the work of Taylor and Delos. The Schrodinger equation is reduced, under certain assumptions, to a non-denumerably infinite set of coupled equations. We develop a new method for solving these equations that is more general than the methods used by Taylor and Delos. A zero-order approximation of our solution is applied to the case of H('-)(D('-)) on Ne collisions, the results are compared with the experimental data, and we find good …
Catastrophes In The Elmo Bumpy Torus, Alkesh R. Punjabi
Catastrophes In The Elmo Bumpy Torus, Alkesh R. Punjabi
Dissertations, Theses, and Masters Projects
Experimentally it is observed that the plasma in Elmo Bumpy Torus (EBT) shows discontinuous changes in the electron line density, electron and ion temperatures and fluctuation levels as the ambient gas pressure or electron cyclotron heating is varied continuously. We use the Point Model of Hedrick et al. for the toroidal core plasma in EBT. The Point Model is not a gradient dynamic system. Hence the Elementary Catastrophe Theory is not directly applicable to the Point Model. Nonetheless, the Point Model equilibria will be shown to exhibit properties which are quite akin to the canonical cusp catastrophe. The ambipolar electric …
Long-Time States Of Inverse Cascades In The Presence Of A Maximum Length Scale, Murshed Hossain
Long-Time States Of Inverse Cascades In The Presence Of A Maximum Length Scale, Murshed Hossain
Dissertations, Theses, and Masters Projects
It is shown numerically, both for the two-dimensional Navier-Stokes equations and for two-dimensional magnetohydrodynamics, that the long-time asymptotic state in a forced inverse-cascade situation is one in which the spectrum is completely dominated by its own fundamental. The growth continues until the fundamental is dissipatively limited by its own dissipation rate. An algebraic model is proposed for the dynamics of such a final state.
A Precision Measurement Of The Magnetic Moment Of The Sigma Minus Hyperon, David William Hertzog
A Precision Measurement Of The Magnetic Moment Of The Sigma Minus Hyperon, David William Hertzog
Dissertations, Theses, and Masters Projects
A new measurement of the magnetic moment of the (SIGMA)('-) hyperon has been made and the result is (mu)((SIGMA)('-)) = -1.111 (+OR-) 0.031 (+OR-) 0.011 nuclear magnetons.;Negative kaons from a low-energy separated beam at the Alternating Gradient Synchrotron of the Brookhaven National Laboratory were brought to rest in a novel laminar target consisting of thin metal foils immersed in liquid hydrogen. The production of (SIGMA)('-) hyperons occurred primarily through the reaction K('-)p(--->)(SIGMA)('-)(pi)('+). (SIGMA)('-) hyperon production was tagged by the identification of the energetic (pi)('+). Many of the (SIGMA)('-) so produced stopped in nearby foils of Pb (or W) where …
Atlas Of High Resolution Infrared Spectra Of Carbon Dioxide: February 1983 Edition, D. Chris Benner
Atlas Of High Resolution Infrared Spectra Of Carbon Dioxide: February 1983 Edition, D. Chris Benner
Arts & Sciences Articles
No abstract provided.
Nmr Study Of Molecular Motions In Two Disordered Organic Solids, Philip L. Kuhns
Nmr Study Of Molecular Motions In Two Disordered Organic Solids, Philip L. Kuhns
Dissertations, Theses, and Masters Projects
The molecular motions are studies in two disordered materials that undergo glass transitions. Glycerol is a conventional glass former and cyclohexanol is an orientational glass former.;The technique used in the glycerol experiments was spectral hole burning. Chemical shift anisotropy produces inhomogeneous broadening of NMR lines in orientationally disordered and polycrystalline solids. By saturating or inverting a portion of the anisotropic line, 'burning a hole', molecules of certain orientations are tagged. Subsequent molecular reorientations result in spectral diffusion which is not related to spin-spin interactions. By measuring the broadening and recovery of the hole as a function of time, detailed knowledge …