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The (t,d) reaction on the Ni isotopes with polarized tritons

The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.

Date: January 1, 1980

Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Selective population of high-j states via heavy-ion-induced transfer reactions

One of the early hopes of heavy-ion-induced transfer reactions was to populate states not seen easily or at all by other means. To date, however, I believe it is fair to say that spectroscopic studies of previously unknown states have had, at best, limited success. Despite the early demonstration of selectivity with cluster transfer to high-lying states in light nuclei, the study of heavy-ion-induced transfer reactions has emphasized the reaction mechanism. The value of using two of these react… more

Date: January 1, 1982

Creator: Bond, P.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Background radiation from fission pulses

Extensive source terms for beta, gamma, and neutrons following fission pulses are presented in various tabular and graphical forms. Neutron results from a wide range of fissioning nuclides (42) are examined and detailed information is provided for four fuels: /sup 235/U, /sup 238/U, /sup 232/Th, and /sup 239/Pu; these bracket the range of the delayed spectra. Results at several cooling (decay) times are presented. For ..beta../sup -/ and ..gamma.. spectra, only /sup 235/U and /sup 239/Pu result… more

Date: May 1, 1988

Creator: England, T. R.; Arthur, E. D.; Brady, M. C. & LaBauve, R. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Radio chemistry as a diagnostic in laser fusion experiments

Nuclear chemistry techniques have been employed in an attempt to measure the density of high compression laser fusion targets. Radioactive /sup 28/Al atoms formed in the /sup 28/Si(n,p)/sup 28/Al reaction arising from the interaction of the 14 MeV neutrons with the silicon atoms in the glass microsphere have been counted at Lawrence Livermore Laboratory using a ..beta..-..gamma.. coincidence method. The detection system that is employed allows activities corresponding to 100 aluminum atoms to b… more

Date: November 1, 1977

Creator: Campbell, E.M.; Hicks, H.G.; Mead, W.C.; Glaros, S.S.; Coleman, L.W. & Laird, W.B.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Particle production and spectra in E802 at BNL-AGS

The production of {pi}, K, and protons measured in the E802 spectrometer are studied for p+A and Si+A collisions. Systematic properties of particle spectra and rapidity density distributions are discussed in terms of centrality and reaction system. A detailed comparison of the data to the RQMD model, which employs the experimental acceptance and cuts are presented. 8 refs., 6 figs.

Date: January 1, 1991

Creator: Videbaek, F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Linear accelerator driven (LADR) and regenerative reactors (LARR) for nuclear non-proliferation

Linear accelerator breeders (LAB) could be used to produce fissile fuel in two modes, either with fuel reprocessing or without fuel reprocessing. With fuel reprocessing, the fissile material would be separated from the target and refabricated into a fuel element for use in a burner power reactor. Without reprocessing, the fissile material would be produced in-situ, either in a fresh fuel element or in a depleted or burned element after use in a power reactor. In the latter mode the fissile mate… more

Date: September 1, 1977

Creator: Steinberg, M.; Takahashi, H.; Powell, J. R. & Kouts, H. J.C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Exploding pusher performance at fixed laser power, a theoretical model

A model for the physics of exploding pusher targets is presented which compares favorably with the predictions of the complex simulation code, LASNEX.

Date: October 4, 1977

Creator: Rosen, M.D. & Nuckolls, J.H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design of neutron streak camera for fusion diagnostics

The D-T burn time for advanced laser-fusion targets is calculated to be very short, < 50 ps. We describe the design of a neutron streak camera of 16 ps resolving time that can be used to study the temporal history of fusion burn. The cathode of the neutron streak camera is sensitive to neutrons and is curved such that the difference in the neutron path lengths from a point source to various parts of the cathode is compensated by electron transit times within the streak tube. Thus the cathode ca… more

Date: June 1, 1982

Creator: Wang, C. L.; Kalibjian, R. & Singh, M. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Study of Isovector Resonances With Pion Charge Exchange

Studies with the pion charge exchange reactions (..pi../sup +-/,..pi../sup 0/) at 164 MeV using the LAMPF ..pi../sup 0/ spectrometer are yielding new results on the existence and systematic features of isovector resonances in nuclei. These experiments possess an unusually high signal/background ratio for isovector resonances of low-multipolarity. Results obtained to date are: (1) observation and angular disribution measurement of the giant dipole resonance in nuclei /sup 12/C, /sup 40/Ca, /sup … more

Date: January 1, 1982

Creator: Baer, H.W.; Bolton, R. & Bowman, J.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preparation of curium-americium oxide microspheres by resin-bead loading

Resin-bead loading and calcination techniques have been used to produce all curium and americium oxide feed material (about 2.2 kg) for HFIR targets since 1971. The process based on Dowex 50W resin has progressed from a series of test runs, through special production runs, into routine production in permanent equipment beginning in 1975. Key attributes of this process are its reliability, high yields, and ease of operation. The process is suited for remote operation in hot cells. Yields approac… more

Date: January 1, 1980

Creator: Chattin, F. R.; Benker, D. E.; Lloyd, M. H.; Orr, P. B.; Ross, R. G. & Wiggins, J. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Pseudorapidity densities and fluctuations in central sup 32 S interactions at 200A GeV

Observations of heavy ion interactions at the highest available accelerator energies provide essential information for the analysis and interpretation of cosmic ray interactions. We report on an experiment in which emulsion chamber detectors were exposed to beams of 200A GeV {sup 32}S ions at the CERN SPS. We present statistical features of pseudorapidity distributions from central collisions in the experimental sample and compare them with the predictions from the Lund Model (FRITIOF) which co… more

Date: January 1, 1990

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutron total cross section measurements for /sup 249/Bk and /sup 249/Cf

Total neutron cross sections have been measured for /sup 249/Bk and its ..beta.. decay daughter, /sup 249/Cf. Single level Breit-Wigner resonance analysis has been performed for 35 resonances below 62 eV in Bk and for 10 resonances below 10 eV in Cf. (SDF)

Date: January 1, 1977

Creator: Benjamin, R. W.; Harvey, J. A. & Hill, N. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Profile modification by the ponderomotive force in spherical targets

Experiments have been performed by LLL which indicate a definite density profile steepening. One possible mechanism for this effect is the ponderomotive force. LASNEX has been modified to include the light momentum deposition in the form rho dv/dt = -nabla P - nabla(radical epsilon + radical 1/epsilon) I/2c. Results will be presented from numerical simulations on spherical glass targets at laser intensities from 10/sup 14/ to 10/sup 16/ watts/cm/sup 2/. Emphasis is placed on the nature of the d… more

Date: October 26, 1977

Creator: Larsen, J. T. & Harte, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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RADIOISOTOPES AND RADIATION APPLICATIONS. Quarterly Progress Report No. 12

Continued research is reported in the areas of intrinsic radioactive tracers for industrial process control and the effects of structural factors on radioinduced graft polymerization. The use of Be-- Po neutron sources for production of short-lived isotopes is being investigated. Data are included on the effects of target volume, high-Z scattering media, target-isotope concentration, and macroscopic cross-section on speciflc and total activation produced with a 10-curie source. Research on graf… more

Date: April 18, 1962

Creator: Sunderman, D.N. ed.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Exploding pusher targets for the SHIVA laser system

The first targets for the 20 TW SHIVA laser system were designed. They are simple glass micro-balloons, approximately 300 ..mu..m in diameter and 2 ..mu..m thick, filled with D-T gas. Using LASNEX, whose model physics was utilized successfully for ARGUS targets, we optimize for both gain and yield. The target behaves as an exploding pusher. Different simple analytic models for the physics of this mode are presented, and are tested by comparing their scaling predictions, at constant absorbed pow… more

Date: September 26, 1977

Creator: Rosen, M. D.; Larsen, J. T. & Nuckolls, J. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Evaluation of the /sup 232/Th neutron capture cross section above 3 keV

This memo describes an evaluation of the /sup 232/Th neutron capture cross section in the neutron energy range from 3 keV to 20 MeV. Most existing differential measurements are reviewed, and some data are renormalized to current values of the standards. Several experimentally determined sets of average resonance parameters are also discussed. From 3 to 50 keV the evaluated cross section is described by a set of average statistical resonance parameters. Above 50 keV the evaluated capture cross s… more

Date: December 1, 1977

Creator: de Saussure, G. & Macklin, R.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Optimum collection time for short-lived isotopes

In dealing with an isotope whose half-life is comparable to the processing time, the target-maker wishes to terminate the procedure at a point that will maximize the amount of the desired material on the target. This cut-off time is not always easy to determine; while it is true that fresh material is constantly being deposited, the isotope previously laid down is steadily decaying, and in addition the rate at which fresh material is applied is usually decreasing. The purpose of this paper is t… more

Date: January 1, 1977

Creator: Lerner, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Preliminary results from collisions between 3. 2-TeV /sup 16/O and target nuclei of C, Cu, and Au

We have presented preliminary WA80 data from interactions of /sup 16/O with C, Cu, and Au at 60 and 200 GeVnucleon. These have included total charged-particle multiplicity distributions and transverse energy distributions. Ranges of transverse momentum per particle and of possible energy densities were discussed. Some of the unique features of WA80 were stressed. These are: complete coverage of the target rapidity region, complete coverage of charged-particle multiplicity measurement, and measu… more

Date: January 1, 1987

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Simple scaling model for exploding pusher targets

A simple model has been developed which when normalized by experiment or Lasnex calculations can be used to scale neutron yields for variations in laser input power and pulse length and target radius and wall thickness. The model also illucidates some of the physical processes occurring in this regime of laser fusion experiments. Within certain limitations on incident intensity and target geometry, the model scales with experiments and calculations to within a factor of two over six decades in … more

Date: November 4, 1977

Creator: Storm, E. K.; Larsen, J. T.; Nuckolls, J. H.; Ahlstrom, H. G. & Manes, K. R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Design studies of a laser fusion power plant

The conceptual design of a laser fusion power plant has been undertaken to exploit recent developments in target design. Advanced high-gain targets which have been developed make it possible to significantly relax the laser and optical system requirements. The power plant design features a reactor concept which utilizes a thick falling region of liquid lithium to protect the first-wall from the neutrons, x-rays, and charged particles that are produced in the thermonuclear microexplosion. The li… more

Date: October 7, 1977

Creator: Maniscalco, J. A.; Meier, W. R. & Monsler, M. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Lawrence Livermore National Laboratory laser-fusion program

The goals of the Laser-Fusion Program at Lawrence Livermore National Laboratory are to produce well-diagnosed, high-gain, laser-driven fusion explosions in the laboratory and to exploit this capability for both military applications and for civilian energy production. In the past year we have made significant progress both theoretically and experimentally in our understanding of the laser interaction with both directly coupled and radiation-driven implosion targets and their implosion dynamics.… more

Date: July 12, 1982

Creator: Ahlstrom, H.G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Neutralization of H/sup -/ beams with gas jets

A test facility was constructed to create a compact curtain-shaped gas jet as a first-generation operational neutralizer for the 150 keV H/sup -/ beam. Different gases and vapors were considered, their optimum target thicknesses and neutralization efficiencies with respect to beam energies were explored. Two techniques of gas jet formation were compared. Multiparallel-channel effusive jets of CO/sub 2/ and H/sub 2/ were selected as test candidates.

Date: January 1, 1977

Creator: Lam, C. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Heavy ion induced transfer reactions: a spectroscopic tool for high spin states

By selectively choosing the appropriate heavy ion transfer reaction one can access high spin states. As a demonstration of the technique two proton and two neutron states of high spin (both yrast and non-yrast) in Nd nuclei have been identified. These spectroscopic results have yielded the first direct information about the configuration of some of these states. 11 refs., 6 figs. (WRF)

Date: January 1, 1985

Creator: Bond, P.D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Nuclear-spectroscopy problems studied with neutrons

Nuclear spectroscopy with neutrons continues to have a major impact on the progress of nuclear science. Neutrons, being uncharged, are particularly useful for the study of low energy reactions. Recent advances in time-of-flight spectroscopy, as well as in the gamma ray spectroscopy following neutron capture, have permitted precision studies of unbound and bound nuclear levels and related phenomena. By going to new energy domains, by using polarized beams and targets, through the invention of ne… more

Date: January 1, 1982

Creator: Raman, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department