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in creator/contributor: "Datz, S."

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Strong forward-backward asymmetries in electron emission from overlapping resonance states in fast C/sup 3 +/ on He collisions

Autoionizing electrons from the configuration 1s/sup 2/2pnl produced by transfer and excitation were measured for 2.5 to 5.0 MeV C/sup 3 +/ + He-gas collision employing the method of zero-degree Auger spectroscopy. The elctron analyzer was operated with an energy resolution of 300 MeV (FWHM), which corresponds to the projectile rest frame energy resolution (approx.40 MeV). (WRF)

Date: January 1, 1986

Creator: Yamazaki, Y.; Miller, P. D.; Krause, H. F.; Pepmiller, P. L.; Datz, S. & Sellin, I. A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Collisional-electron detachment of Cl/sup -/ on diatomic molecules

Recent experimental results for collisional-electron detachment of Cl/sup -/ by H/sub 2//D/sub 2/, N/sub 2/, O/sub 2/, NO, and CO are discussed. The emphasis is on angular distributions and energy loss measurements for laboratory energies of a few hundred eV. Evidence for the possibility of bound excited states of N/sub 2/Cl and COCl and the role of target negative-ion resonant states is presented.

Date: January 1, 1981

Creator: Annis, B.K. & Datz, S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Energy and angular distribution of low energy H/sup +/ and D/sup +/ backscattered from polycrystalline carbon

The energy distributions of H/sup +/ and D/sup +/ backscattered from a polycrystalline graphite sample were recorded as a function of total scattering angle, angle of incidence, and for incident beam energies 200 < E/sub i/ < 3000 eV. The general shapes of the distributions are discussed qualitatively, and their variation with incident energy and total scattering angle are explained and compared with theoretical and other experimental results. The average energies E/sup - +/, of the distributio… more

Date: January 1, 1980

Creator: Overbury, S.H.; Dittner, P.F.; Datz, S. & Thoe, R.S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Experimental atomic physics in heavy-ion storage rings

This paper outlines the discussion which took place at the ''round table'' on experimental atomic physics in heavy-ion storage rings. Areas of discussion are: electron-ion interactions, ion-ion collisions, precision spectroscopy of highly charged ions, beta decay into bound final states, and atomic binding energies from spectroscopy of conversion elections. 18 refs., 1 tab. (LSP)

Date: January 1, 1987

Creator: Datz, S.; Andersen, L.H.; Briand, J.P. & Liesen, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Planar Channeling Radiation From Relativistic Positrons and Electrons in LiF

Channeling radiation has been measured for planar-channeled 54- and 83-MeV positrons and 17-, 31-, and 54-MeV electrons in the ionic crystal LiF. The results are shown to be in reasonable, but not perfect, agreement with the results of many-beam calculations based upon a model of the crystal as an array of isolated Li/sup +/ and F/sup -/ ions.

Date: July 1, 1983

Creator: Berman, B. L.; Datz, S.; Fearick, R. W.; Swent, R. L.; Pantell, R. H.; Park, H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Correlated Two Electron Effects in Collisions of Multiply Charged Au Ions with He

We have studied the fate of electrons released in collisions between highly charged Au/sup q+/ ions (20 MeV) and He atoms and find that the large transfer ionization (TI) cross section observed can be accounted for by transfer of two electrons to a highly correlated state on the Au projectile followed by the loss of one electron to the continuum. Autoionization lines are also observed, but they are attributable to electron transfer accompanied by core excitation (TE).

Date: January 1, 1984

Creator: Datz, S.; Bottcher, C.; Andersen, L.H.; Hvelplund, P. & Knudsen, H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Monte Carlo calculations of channeling radiation

Results of classical Monte Carlo calculations are presented for the radiation produced by ultra-relativistic positrons incident in a direction parallel to the (110) plane of Si in the energy range 30 to 100 MeV. The results all show the characteristic CR(channeling radiation) peak in the energy range 20 keV to 100 keV. Plots of the centroid energies, widths, and total yields of the CR peaks as a function of energy show the power law dependences of ..gamma../sup 1/ /sup 5/, ..gamma../sup 1/ /sup… more

Date: January 1, 1981

Creator: Bloom, S. D.; Berman, B. L.; Hamilton, D. C.; Alguard, M. J.; Barrett, J. H.; Datz, S. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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On the utility and ubiquity of atomic collision physics

This paper is divided into three parts. In the introduction, we discuss the history and makeup of ICPEAC. In the second part, we discuss the extent of applicability of atomic collision physics. In the third part, we chose one subject (dielectronic excitation) to show the interrelationship of various sub-branches of atomic collision physics. 28 refs., 14 figs.

Date: January 1, 1989

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Production of autoionizing Rydberg states by transfer excitation in high energy ion atom collisions

The method of zero-degree Auger spectroscopy was used to study the production of autoionizing Rydberg states in collisions of carbon and oxygen projectiles incident at several MeV on He gas and carbon foils. The autoionization electrons were measured with high resolution so that the quantum defect corresponding to the angular momenta of the Rydberg electrons could be observed. The main purpose of the present experiment is to gain information about the n and l distribution of the Rydberg electro… more

Date: January 1, 1986

Creator: Stolterfoht, N.; Miller, P. D.; Krause, H. F.; Yamazaki, Y.; Dittner, P. F.; Pepmiller, P. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Summary of informal workshop on state of ion beam facilities for atomic physics research

The present state of ion beam facilities for atomic physics research in the United States is assessed by means of a questionnaire and informal workshop. Recommendations for future facilities are given. 3 refs.

Date: November 13, 1984

Creator: Jones, K. W.; Cocke, C. L.; Datz, S. & Kostroun, V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Experimental approaches to the measurement of dielectronic recombination

In dielectronic recombination, the first step involves a continuum electron which excites a previously bound electron and, in so doing, loses just enough energy to be captured in a bound state (nl). This results in a doubly excited ion of a lower charge state which may either autoionize or emit a photon resulting in a stabilized recombination. The complete signature of the event is an ion of reduced charge and an emitted photon. Methods of measuring this event are discussed.

Date: January 1, 1984

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Radiation From Channeled Electrons and Positrons

Channeling radiation is generally described as arising from radiative transitions between bound states in a continuum potential. The concept of the continuum potential is used in connection with the channeling (directed motion) of heavy, positively charged particles penetrating crystals along a low-index axial or planar direction. If a positively charged particle is injected into a crystal at a small angle with respect to an atomic row (a crystal axis), it will undergo a set of small-angle corr… more

Date: 1986

Creator: Datz, S.; Berman, B. L.; Pantell, R. H. & Kephart, J. O.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Atomic physics using large electrostatic accelerators

This article surveys some areas of atomic physics using large electro-static accelerators. Brief overviews of ion-atom collisions and ion-solid collisions are followed by a classified listing of recent paper. A single line, correlated electron ion recombination, is chosen to show the recent development of techniques to study various aspects of this phenomenon. 21 refs., 11 figs., 1 tab.

Date: January 1, 1989

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Electron-positron pair production in ultrarelativistic atomic collisions: 6.4 TeV S{sup 16+} with Au, Pd and Al

Angular and momentum distributions have been measured for electron-positron pairs created in peripheral collisions of 6.4 TeV bare sulfur ions with thin targets of Al, Pd, and Au. Singly- and doubly-differential cross sections are presented for 1--17 MeV/c electrons and positrons detected independently and in coincidence as pairs. Various physical parameters are deduced from the coincident electron and positron data, including probability distributions for the pair transverse momentum, the pair… more

Date: October 1, 1994

Creator: Datz, S.; Vane, C. R.; Dittner, P. F.; Krause, H. F.; Schuch, R.; Gao, H. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Atomic physics experiments with stored cooled heavy ion beams

The wide ranging interest in the development of heavy ion synchrotrons with electron beam cooling is evident from the number of projects presently under way. Although much of the initial motivation for these rings stemmed from nuclear and particle physics, a considerable amount of atomic physics experimentation is planned. This paper surveys some of the new opportunities in atomic physics which may be made available with storage ring systems. 25 refs., 3 tabs.

Date: January 1, 1986

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Electronic states of ions recoiling into vacuum and gases

No Description Available.

Date: January 1, 1973

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Coherent absorption and emission processes of energetic particles penetrating crystals

Swift charged particles moving through an ordered array of atoms in a crystal experience periodic perturbations which can give rise to coherent absorption or emission of photons. Indeed the phenomenon of coherent bremsstrahlung arising from ultrarelativistic electron penetration of crystals has been studied for many years. The complexity of the Fourier components of the electric field experienced by the particle is greatly reduced if the direction of motion lies along a crystal axis or in a cry… more

Date: January 1, 1980

Creator: Datz, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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HISTRAP Proposal: Heavy Ion Storage Ring for Atomic Physics

HISTRAP, Heavy Ion Storage Ring for Atomic Physics, is a proposed 46.8-m-circumference synchrotron-cooling-storage ring optimized to accelerate, decelerate, and store beams of highly charged very-heavy ions at energies appropriate for advanced atomic physics research. The ring is designed to allow studies of electron-ion, photon-ion, ion-atom, and ion-ion interactions. An electron cooling system will provide ion beams with small angular divergence and energy spread for precision spectroscopic s… more

Date: November 1, 1986

Creator: Olsen, D. K.; Alton, G. D.; Datz, S.; Dittner, P. F.; Dowling, D. T.; Haynes, D. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

HISTRAP Proposal: Heavy Ion Storage Ring for Atomic Physics

HISTRAP is a proposed synchrotron-cooling-storage ring optimized to accelerate, decelerate, and store beams of highly charged very-heavy ions at energies appropriate for advanced atomic physics research. The ring is designed to allow studies of electron-ion, photon-ion, ion-atom, and ion-ion interactions. An electron cooling system will provide ion beams with small angular divergence and energy spread for precision spectroscopic studies and also is necessary to allow the deceleration of heavy i… more

Date: January 1, 1986

Creator: Olsen, D. K.; Alton, G. D.; Datz, S.; Dittner, P. F.; Dowling, D. T.; Haynes, D. L. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Resonant coherent excitation of N{sup 6+} and Mg{sup 11+} in planar channeling: Anisotropies in ionization probabilities and x-ray emission

The thrust of the conference in which this paper is presented is toward inelastic interactions of ions with surfaces. The work described in this paper deals with inelastic interactions of ions in planar channeling inside the crystal. The authors are, however, not too far off the mark because the planar channeling potential is made up from the sum of two (sheet) surface potentials. For the nitrogen experiment, a beam of N{sup 6+} ions at an energy of 3.25 MeV/amu was supplied by the ORNL EN Tand… more

Date: December 31, 1994

Creator: Datz, S.; Dittner, P. F.; Krause, H. F.; Vane, C. R.; Crawford, O. H.; Forster, J. S. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Dissociative recombination of stored and phase-spaced cooled molecular ions in CRYRING

Ion storage rings offer several advantages for studies of recombination of molecular ions by electrons, a process which in general leads to dissociation. During the last year dissociative recombination of H{sub 3}{sup +}, HD{sup +}, H{sub 2}{sup +}, D{sub 2}{sup +}, {sup 3}HeH{sup +}, {sup 4}HeH{sup +} and {sup 4}HeD{sup +} have been studied in storage rings in Stockholm, Heidelberg, Tokyo and Aarhus. Only a fraction of the results obtained at these places have been processed to the point where… more

Date: November 1, 1993

Creator: Larsson, M.; Sundstroem, G.; Carlson, M.; Danared, H.; Kaellberg, A.; Rensfelt, K. G. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Investigations of radiative electron capture by ion channeling techniques

The unique constraints imposed on the interactions of energetic heavy ions as a result of the channeling effect are utilized to investigate the phenomenon of radiative electron capture (REC) for 17 to 40 MeV oxygen ions. Measured cross-sections and widths of the REC radiation are compared with calculations made specifically for the channeling situation.

Date: February 1, 1976

Creator: Appleton, B. R.; Ritchie, R. H.; Biggerstaff, J. A.; Noggle, T. S.; Datz, S.; Moak, C. D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Excitation curve for auger decay of the (1S2S2P sup 2 ) sup 3 D state of C sup 4+ formed through RTE (Resonant Transfer and Excitation)

The ORNL EN tandem supplied beams of 3.5--9 MeV C{sup 3+} ions which were incident on a differentially pumped He target. Auger electrons emitted by fast C{sup 4+} ions emerged at 10 deg(lab)w.r.t. the incident ion beam. They were detected using a two stage spectrometer with kinematic refocusing. An excitation curve was obtained for the (1s2s2p){sup 3}D state Auger decay to the ground state of C{sup 3+}. The excitation curve peaks at {approximately}6 MeV, which strongly supports the notion that … more

Date: January 1, 1990

Creator: Shafroth, S. M.; McDonald, F.; Benhenni, M. (North Carolina Univ., Chapel Hill, NC (USA)); Kessel, Q.; Deveney, E. (Connecticut Univ., Storrs, CT (USA)); Swenson, J. K. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Surgery of fast, highly charged ions studied by zero-degree Auger spectroscopy

Zero-degree Auger spectra were measured in collisions of oxygen and carbon on He with incident charge states of q = 2 to 5 and for energies from 5 to 30 MeV. Since the light target particle He acts selectively on the projectile ion, we refer to the present method as ion surgery. Apart from the one-electron processes single excitation and single loss, two-electron processes such as transfer excitation and transfer loss are studied. 17 refs., 4 figs., 1 tab.

Date: January 1, 1986

Creator: Stolterfoht, N.; Miller, P. D.; Krause, H. F.; Yamazaki, Y.; Swenson, J. K.; Bruch, R. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department