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Cs/sup +/ + Cs/sup +/ charge-transfer and ionization cross-section measurements by a plasma-target technique

Description: A Q machine plasma target using cesium was constructed to serve as a target for a beam of Cs/sup +/ ions. The sum of charge transfer and ionization cross sections was determined by measuring the growth of the Cs/sup + +/ component of the beam as a function of the plasma radial line density. The measured cross section varies approximately linearly with energy between 50 and 110 keV. This loss cross section is 0.47 +- .11 x 10/sup -16/ cm/sup 2/ at 110 keV. These results have been compared to the… more
Date: May 1, 1982
Creator: Stalder, K.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Model for H/sup -/ and D/sup -/ production by hydrogen backscattering

Description: The Marlowe Monte-Carlo backscattering code has been used to calculate particle reflection coefficients and energy distributions for H, D incident upon Li, K, Ni, Cu, Mo, Ag, Cs, Hf, W, Pt, and U surfaces. The backscattered energy and angular distributions are combined with a model for formation and survival probabilities for H/sup -/, D/sup -/ leaving the surface. A least-squares fit of experimental measurements of H/sup -/ yields from the composite surface, Cs/Cu, has been used to obtain two … more
Date: May 27, 1980
Creator: Hiskes, J.R. & Schneider, P.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Total and differential electron collision cross sections for O/sub 2/ and N/sub 2/

Description: We present a compilation of total and differential cross sections for electron scattering of N/sub 2/ and O/sub 2/. Energy-dependent total cross sections and energy- and angle-dependent differential cross sections are given for elastic, rotational, vibrational, electronic excitation, and ionizing collisions. 16 refs., 46 figs., 8 tabs.
Date: May 1, 1988
Creator: Murphy, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Proceedings of the Workshop on Electronic and Ionic Collision Cross Sections Needed in the Modeling of Radiation Interactions with Matter, Held at Argonne National Laboratory December 6-8, 1983

Description: The term modeling in the Workship title refers to the mathematical analysis of the consequences of many collision processes for characterizing the physical stage of radiation actions. It requires as input some knowledge of collision cross sections. Traditionally, work on cross sections and work on the modeling are conducted by separate groups of scientists. It was the purpose of the Workshop to bring these two groups together in a forum that would promote effective communication. Cross-section … more
Date: May 1984
Creator: Argonne National Laboratory
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Transition radiation as a practical x-ray source

Description: Transition radiation is generated when an energetic electron crosses the boundary between two different media. Theoretical calculations predict soft x-ray spectra and angular distributions that agree with experimental results. Further, recent advances in microstructure technology create the possibility of designing transition-radiation sources for several practical applications. For example, calculations indicate that a stack of 60 1..mu..m-thick beryllium foils exposed to a beam of 100 MeV ele… more
Date: May 1, 1985
Creator: Moran, M. J. & Ebert, P. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

[News Script: Lewisville man]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas, relating a news story about the state highway patrol in Louisiana reporting that a 55-year old man from Lewisville was killed in a traffic accident.
Date: May 29, 1972, 10:00 p.m.
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Script
Partner: UNT Libraries Special Collections
open access

TEMPEST Simulations of Collisionless Damping of Geodesic-Acoustic Mode in Edge Plasma Pedestal

Description: The fully nonlinear (full-f) 4D TEMPEST gyrokinetic continuum code produces frequency, collisionless damping of GAM and zonal flow with fully nonlinear Boltzmann electrons for the inverse aspect ratio {epsilon}-scan and the tokamak safety factor q-scan in homogeneous plasmas. The TEMPEST simulation shows that GAM exists in edge plasma pedestal for steep density and temperature gradients, and an initial GAM relaxes to the standard neoclassical residual, rather than Rosenbluth-Hinton residual due… more
Date: May 30, 2007
Creator: Xu, X. Q.; Xiong, Z.; Nevins, W. M. & McKee, G. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

TEMPEST Simulations of Collisionless Damping of Geodesic-Acoustic Mode in Edge Plasma Pedestal

Description: The fully nonlinear 4D TEMPEST gyrokinetic continuum code produces frequency, collisionless damping of geodesic-acoustic mode (GAM) and zonal flow with fully nonlinear Boltzmann electrons for the inverse aspect ratio {epsilon}-scan and the tokamak safety factor q-scan in homogeneous plasmas. The TEMPEST simulation shows that GAM exists in edge plasma pedestal for steep density and temperature gradients, and an initial GAM relaxes to the standard neoclassical residual, rather than Rosenbluth-Hin… more
Date: May 31, 2007
Creator: Xu, X; Xiong, Z; Nevins, W & McKee, G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
captions transcript

[News Clip: Police wreck]

Description: B-roll video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: May 5, 1980, 6:00 p.m.
Duration: 49 seconds
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Item Type: Refine your search to only Video
Partner: UNT Libraries Special Collections
open access

Topics in bound-state dynamical processes: semiclassical eigenvalues, reactive scattering kernels and gas-surface scattering models

Description: The difficulty of applying the WKB approximation to problems involving arbitrary potentials has been confronted. Recent work has produced a convenient expression for the potential correction term. However, this approach does not yield a unique correction term and hence cannot be used to construct the proper modification. An attempt is made to overcome the uniqueness difficulties by imposing a criterion which permits identification of the correct modification. Sections of this work are: semiclas… more
Date: May 1, 1979
Creator: Adams, J.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Overview on collision processes of highly charged ions with atoms present status and problems

Description: This paper provides a brief discussion on the present status of the collision physics of highly charged ions with atoms. The emphasis is on the main achievements in understanding and describing the most important collision processes, and as charge transfer, ionization and Auger-type processes, and even more on those open problems which, due either to their scientific or practical importance, represent challenges to current research in this field. The paper concentrates on general ideas and prob… more
Date: May 1, 1983
Creator: Janev, R.K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Surface modification of solids

Description: The use of ion beam and pulsed laser processing is reviewed for the near-surface modification of a wide range of materials. The techniques of ion implantation doping, ion beam and laser mixing, and pulsed-laser annealing are stressed with particular emphasis on the nonequilibrium aspects of these processing techniques and on new materials properties which can result. Examples are presented illustrating the utility of these techniques for fundamental materials research as well as practical surfa… more
Date: May 1, 1984
Creator: Appleton, B. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Photodissociation Processes in Molecular Beams

Description: A description is presented of a study of the photodissociation dynamics of molecules in a molecular beam. Photo-fragmentation translational spectroscopy has been utilized to observe the photodissociation dynamics of ozone. Using a supersonic molecular beam and a 10 nanosecond pulsed laser at lambda = 266 nm, the velocities of the fragment products are measured by the method of time of flight. The resolution of the time of flight spectrum of ozone is sufficiently high that the electronic and vib… more
Date: May 1, 1979
Creator: Carlson, L. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Collisions of fast multicharged ions in gas targets: charge transfer and ionization

Description: Measurements of cross sections for charge transfer and ionization of H/sub 2/ and rare-gas targets have been made with fast, highly stripped projectiles in charge states as high as 59+. We have found an empirical scaling rule for electron-capture cross section in H/sub 2/ valid at energies above 275 keV/amu. Similar scaling might exist for other target gases. Cross sections are generally in good agreement with theory. We have found a scaling rule for electron loss from H in collisions with a fa… more
Date: May 1, 1981
Creator: Schlachter, A.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Charge-changing collisions

Description: Recent results for charge-changing collisions of interest for cyclotrons and other particle accelerators are presented. Scaling rules, where available, are emphasized. 45 references, 11 figures.
Date: May 1, 1984
Creator: Schlachter, A.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Opportunities and requirements for experimentation at high energy e/sup +/e/sup /minus// collider

Description: Over the past fifteen years of high-energy physics, electron-positron annihilation has been the most productive of all reactions probing the fundamental interactions. The e/sup +/e/sup /minus// annihilation process is unique in offering at the same time copious production of novel particles, low backgrounds from more conventional physics, and the most efficient use of the energy which an accelerator provides. These features have allowed the detailed characterization of the charm and bottom quar… more
Date: May 1, 1988
Creator: Ahn, C.; Baltay, C.; Barklow, T. L.; Burchat, P. R.; Burke, D. L.; Cooper, A. R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Workshop on electronic and ionic collision cross sections needed in the modeling of radiation interactions with matter: proceedings

Description: The term modeling in the Workship title refers to the mathematical analysis of the consequences of many collision processes for characterizing the physical stage of radiation actions. It requires as input some knowledge of collision cross sections. Traditionally, work on cross sections and work on the modeling are conducted by separate groups of scientists. It was the purpose of the Workshop to bring these two groups together in a forum that would promote effective communication. Cross-section … more
Date: May 1, 1984
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Molecular potentials and relaxation dynamics

Description: The use of empirical pseudopotentials, in evaluating interatomic potentials, provides an inexpensive and convenient method for obtaining highly accurate potential curves and permits the modeling of core-valence correlation, and the inclusion of relativistic effects when these are significant. Recent calculations of the X/sup 1/..sigma../sup +/ and a/sup 3/..sigma../sup +/ states of LiH, NaH, KH, RbH, and CsH and the X/sup 2/..sigma../sup +/ states of their anions are discussed. Pseudopotentials… more
Date: May 18, 1981
Creator: Karo, A.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Internal Energy Dependence of Molecular Condensation Coefficients Determined From Molecular Beam Surface Scattering Experiments

Description: An experiment was performed which confirms the existence of an internal mode dependence of molecular sticking probabilities for collisions of molecules with a cold surface. The scattering of a velocity selected effusive beam of CCl{sub 4} from a 90 K CC1{sub 4} ice surface has been studied at five translational velocities and for two different internal temperatures. At a surface temperature of 90 K (approx. 99% sticking probability) a four fold increase in reflected intensity was observed for t… more
Date: May 1, 1978
Creator: Sibener, S.J. & Lee, Y.T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Collisional Processes of Interest in MFE Plasma Research

Description: Research on this grant is devoted to the calculation of heavy particle collision cross sections needed for diagnostic studies of magnetic fusion plasmas. This work requires the development and testing of new theoretical methods, with the implementation of benchmarked techniques to collisions pertinent to fusion reactors. Within the last context, we have provided charge-exchange-recombination cross sections to specific n,1-levels for diagnostic studies on TFTR and for a major compilation for IAE… more
Date: May 24, 1990
Creator: Olson, R. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Resonances in electron-molecule scattering and photoionization

Description: The development of reliable theoretical models for calculating the decay of quasi-stationary states of molecular systems has become an important endeavor for theoretical chemists. The understanding and analysis of a wide variety of physical and chemical phenomena depend on a knowledge of the behavior of these states in both collisional and photoionization problems. In this article we describe the theory and calculation of these cross sections using our Linear Algebraic/Optical Potential method.… more
Date: May 1, 1984
Creator: Schneider, B. I. & Collins, L. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Measurements of scattering processes in negative ion-atom collisions. Technical progress report, 1 September 1992--31 August 1993

Description: This Technical Progress Report describes the progress made on the research objectives during the past twelve months. This research project is designed to provide measurements of various scattering processes which occur in H{sup {minus}} collisions with atomic (specifically, noble gas and atomic hydrogen) targets at intermediate energies. These processes include elastic scattering, single- and double-electron detachment, and target excitation/ionization. For the elastic and target inelastic proc… more
Date: May 1, 1993
Creator: Kvale, T. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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