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Multimode harmonic power measurement of 40 MW pulsed S-band klystrons (open access)

Multimode harmonic power measurement of 40 MW pulsed S-band klystrons

An array of 12 calibrated RF electric field probes on the waveguide walls are used to sample the complex field profile at the second and third harmonics where the fundamental power is in the 40 MW range at 2856 MHx. The measured amplitude and phase signals from these are Fourier analyzed to determine with good accuracy the power in each of the many possible propagating modes.
Date: August 1, 1984
Creator: Fowkes, W. R. & Wu, E. S.
System: The UNT Digital Library
Luminosities for collisions of intermediate bosons and other partons (open access)

Luminosities for collisions of intermediate bosons and other partons

Parton-parton luminosities (l/s) dpounds/d tau are presented for WW, WZ, ZZ, ..gamma..W, ..gamma..Z, ..gamma gamma.., Wg, Wq, Zg, and Zq collisions. A comparison between the exact calculation and the calculation using our luminosities for Higgs boson production from WW fusion is also presented.
Date: August 1, 1984
Creator: Dawson, S.
System: The UNT Digital Library
Preliminary Results of nu/sub e/e/sup -/ Scattering at LAMPF (open access)

Preliminary Results of nu/sub e/e/sup -/ Scattering at LAMPF

We present preliminary results of a neutrino experiment in progress at LAMPF by an Irvine-Los Alamos-Maryland collaboration. We have observed a signal consistent with nu/sub e/e/sup -/ elastic scattering, with a 15-ton sandwich detector. The number of these nu/sub e/e/sup -/ candidates agrees with that predicted by the Weinberg-Salam electroweak theory. The corresponding sin/sup 2/theta/sub w/ and total cross section are reported. This study shows that the interference of weak charged-current and weak neutral-current in nu/sub e/e/sup -/ scattering is not constructive. We also searched for anomalous appearance of anti nu/sub e/ from the LAMPF beam stop. An upper limit for the multiplicative lepton number conservation law, and limits for anti nu/sub ..mu../ ..-->.. anti nu/sub e/ oscillation are given. 15 references.
Date: August 1, 1984
Creator: Allen, R. C.; Bharadwaj, V.; Brooks, G. A.; Chen, H. H.; Doe, P. J.; Hausammann, R. et al.
System: The UNT Digital Library
Evidence for a solar companion star (open access)

Evidence for a solar companion star

Periodicity seen in both the mass extinctions and large impact cratering on earth can be explained if one postulates that the sun has a companion star, orbiting in a moderately eccentric orbit with a major axis of 2.8 light-years. No other explanations that have been suggested are compatible with known facts of physics and astronomy. If the companion is a red dwarf star, the most common kind in the galaxy, then no previous astronomical observations would have found it. A search for red objects with large parallax is now underway at Berkeley, and has a good chance of identifying the star in the near future.
Date: August 1, 1984
Creator: Muller, Richard A.
System: The UNT Digital Library
Simulating supersymmetry at the SSC (open access)

Simulating supersymmetry at the SSC

Careful study of supersymmetric signatures at the SSC is required in order to distinguish them from Standard Model physics backgrounds. To this end, we have created an efficient, accurate computer program which simulates supersymmetric particle production and decay (or other new particles). We have incorporated the full matrix elements, keeping track of the polarizations of all intermediate states. (At this time hadronization of final-state partons is ignored). Using Monte Carlo techniques this program can generate any desired final-state distribution or individual events for Lego plots. Examples of the results of our study of supersymmetry at SSC are provided.
Date: August 1, 1984
Creator: Barnett, R.M. & Haber, H.E.
System: The UNT Digital Library
Use of induction linacs with nonlinear magnetic drive as high average power accelerators (open access)

Use of induction linacs with nonlinear magnetic drive as high average power accelerators

The marriage of induction linac technology with Nonlinear Magnetic Modulators has produced some unique capabilities. It appears possible to produce electron beams with average currents measured in amperes, at gradients exceeding 1 Mev/meter, and with power efficiencies approaching 50%. A 2 MeV, 5 kA electron accelerator is under construction at Lawrence Livermore National Laboratory (LLNL) to allow us to demonstrate some of these concepts. Progress on this project is reported here.
Date: August 20, 1984
Creator: Birx, D. L.; Cook, E. G.; Hawkins, S. A.; Newton, M. A.; Poor, S. E.; Reginato, L. L. et al.
System: The UNT Digital Library
X-ray spectroscopy of laser-produced plasmas (open access)

X-ray spectroscopy of laser-produced plasmas

A brief discussion is given of the importance of x-ray spectroscopy as a diagnostic tool for laser-produced plasma. Of particular note is the role of opacity and time dependence. (MOW)
Date: August 1, 1984
Creator: Kauffman, R.L.
System: The UNT Digital Library
Finite range Droplet Model (open access)

Finite range Droplet Model

A treatment of nuclear masses and deformations is described which combines the Droplet Model with the folding model surface and Coulomb energy integrals. An additional exponential term, inspired by the folding model, but treated here as an independent contribution with two adjustable parameters, is included. With this term incorporated, the accuracy of the predicted masses and fission barriers was improved significantly, the ability of the Droplet Model to account for isotope shifts in charge radii was retained, and the tendency of the Droplet Model to over-predict the surface-tension squeezing of light nuclei was rectified. 20 references, 4 figures.
Date: August 1, 1984
Creator: Moeller, P.; Myers, W.D.; Swiatecki, W.J. & Treiner, J.
System: The UNT Digital Library
Absolute dipole gamma-ray strength functions for /sup 176/Lu (open access)

Absolute dipole gamma-ray strength functions for /sup 176/Lu

We have derived absolute dipole strength-function information for /sup 176/Lu from an average resonance capture study of /sup 175/Lu with 2-keV neutrons, and from neutron capture cross-section measurements with neutrons from 30 keV to about 1 MeV. We found that we needed to increase our previous estimate of the relative M1/E1 strengths near 5 MeV by a factor of 3, and to revise downward the absolute magnitude of our E1 strength function. We accomplished the latter, while still maintaining continuity with the photonuclear data, by adjusting the one free parameter in our line shape. The present E1 and M1 strengths now seem correct both near the neutron separation energy and also around 1 MeV.
Date: August 29, 1984
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
System: The UNT Digital Library
Phase displacement acceleration in the SSC (open access)

Phase displacement acceleration in the SSC

The SSC (Superconducting Super Collider) is supposed to operate with bunched beams and the energy radiated by synchrotron radiation is replaced by the rf-system having a synchronous phase angle slightly different from 180/sup 0/. Here the case of operating the SSC with a coasting beam is considered. In particular the possibility of replacing the radiated energy phase displacement acceleration is investigated.
Date: August 1, 1984
Creator: Hofmann, A.
System: The UNT Digital Library
Isomer ratio calculations using modeled discrete levels (open access)

Isomer ratio calculations using modeled discrete levels

We have calculated isomer ratios for the /sup 175/Lu(n,..gamma..), /sup 175/Lu(n,2n), /sup 237/Np(n,2n), /sup 241/Am(n,..gamma..), and /sup 243/Am(n,..gamma..) reactions using modeled level structures in the deformed, odd-odd product nuclei. We find: that the hundreds of discrete levels and their gamma-ray branching ratios provided by the modeling are necessary to achieve agreement with experiment, that many rotational bands must be included in order to obtain a sufficiently representative selection of K quantum numbers, and that the levels of each band must be extended to appropriately high values of angular momentum. 8 references.
Date: August 29, 1984
Creator: Gardner, M. A.; Gardner, D. G. & Hoff, R. W.
System: The UNT Digital Library
Cerenkov detector for heavy-ion velocity measurements (open access)

Cerenkov detector for heavy-ion velocity measurements

We have developed a highly sensitive velocity measuring detector using total-internal-reflection Cerenkov counters of a type mentioned by Jelly in 1958. If the velocity of the particle is above the threshold for total-internal-reflection these counters have a charge resolution of sigma = 0.18e for a 3mm thick glass radiator. For the velocity measurement we use a fused silica radiator so that the velocity of the particles are near the threshold for total-internal reflection. For momentum-analyzed projectile fragments of 1.6 GeV/nucleon /sup 40/Ar, we have measured a mass resolution of sigma = 0.1u for isotope identification.
Date: August 1, 1984
Creator: Olson, D. L.; Baumgartner, M.; Dufour, J. P.; Girard, J. G.; Greiner, D. E.; Lindstrom, P. J. et al.
System: The UNT Digital Library
Recent particle searches at PEP (open access)

Recent particle searches at PEP

Particle searches discussed include: the TPC search for charge 2/3 and 1/3 particles, e/sup +/e/sup -/ ..-->.. ..gamma gamma.., and supersymmetry searches for electrinos and photinos. (LEW)
Date: August 1, 1984
Creator: Messner, R.L.
System: The UNT Digital Library
Federal laboratories: technology resources and transfer champions (open access)

Federal laboratories: technology resources and transfer champions

The Federal laboratories in the US employ a significant fraction of the nation's research and development resources, including technical staff, facilities and operating budgets. With a maturing base of national policy that encourages technical interchange with industry, universities and state and local governments, and with a breadth of technical areas under study, these laboratories represent a major national contingent asset - valuable yet not fully utilized. The laboratories have developed many methods of interaction with other organizations, providing a variety of ways to match needs and opportunities and to exploit any confluence of interests. The Federal Laboratory Consortium assists these laboratories in their transfer operations and helps to develop linkage opportunities. Many barriers to successful transfer are defined and surmountable.
Date: August 1, 1984
Creator: Stark, E.E. Jr.
System: The UNT Digital Library
Radiation damage in an ethylamine-borane:ammonia target (open access)

Radiation damage in an ethylamine-borane:ammonia target

A polarized target of ethylamine + borane-ammonia + EHBA-Cr(V) was exposed to an integrated beam flux of 10/sup 14/cm/sup 2/. The polarization is shown as a function of proton irradiation. (DLC)
Date: August 27, 1984
Creator: Crabb, D.G. & Hill, D.
System: The UNT Digital Library
Spectroscopy of one- and two-electron uranium (open access)

Spectroscopy of one- and two-electron uranium

The spectra from n = 2 ..-->.. = 1 transitions of hydrogenlike and heliumlike uranium have been observed. Possible experiments to study quantum electrodynamics in these systems are discussed.
Date: August 1, 1984
Creator: Gould, H.
System: The UNT Digital Library
Quadrupole transport experiment with space charge dominated cesium ion beam (open access)

Quadrupole transport experiment with space charge dominated cesium ion beam

The purpose of the experiment is to investigate the beam current transport limit in a long quadrupole-focussed transport channel in the space charge dominated region where the space charge defocussing force is almost as large as the average focussing force of the channel.
Date: August 1, 1984
Creator: Faltens, A.; Keefe, D.; Kim, C.; Rosenblum, S.; Tiefenback, M. & Warwick, A.
System: The UNT Digital Library
Hypermultiplet couplings in N = 2 supergravity (open access)

Hypermultiplet couplings in N = 2 supergravity

An arbitrary number of massless spin (0,/sup 1///sub 2/) multiplets are coupled to N = 2 supergravity, and the scalar fields are found to lie on a negatively curved quaternionic manifold. 6 references.
Date: August 1, 1984
Creator: Bagger, J.
System: The UNT Digital Library
Pulsed rf superconductivity program at SLAC (open access)

Pulsed rf superconductivity program at SLAC

Recent tests performed at SLAC on superconducting TM/sub 010/ caavities using short rf pulses (less than or equal to 2.5 ..mu..s) have established that at the cavity surface magnetic fields can be reached in the vicinity of the theoretical critical fields without an appreciable increase in average losses. Tests on niobium and lead cavities are reported. The pulse method seems to be best suited to study peak field properties of superconductors in the microwave band, without the limitations imposed by defects. The short pulses also seem to be more effective in decreasing the causes of field emission by rf processing. Applications of the pulsed rf superconductivity to high-gradient linear accelerators are also possible.
Date: August 1, 1984
Creator: Campisi, I. E. & Farkas, Z. D.
System: The UNT Digital Library
Results of Thirteen Direct Heat Applications Projects (open access)

Results of Thirteen Direct Heat Applications Projects

The application of geothermal applications is being aided by twenty-three field-experiment projects. The projects provide a current experience base against which the private and municipal sectors can evaluate potential projects and on which they can base their project plans. The results of thirteen of these projects are presented with emphasis on: energy replaced, economic payback, system designs, and resource assessment and development. The thirteen projects currently replace about 58,000 barrels of oil per year and avoid an imported oil cost of $1.7 million/year. They have a future potential of 84,000 barrels/year and $2.5 million/year.
Date: August 1, 1984
Creator: Childs, F. W.
System: The UNT Digital Library
Root adaptations at stress levels of nitrate, phosphate, or both simultaneously (open access)

Root adaptations at stress levels of nitrate, phosphate, or both simultaneously

Sunflowers in flowing hydroponic culture show reduced growth rates at nitrate levels below 10 ..mu..M nitrate or phosphate levels below 0.3 ..mu..F. At least for phosphate, this level is a very small fraction (0.003) of the K/sub m/ for the uptake systems. We have quantified four major adaptations that enable high growth rates under incipient stress: increased root:shoot ratio; increased uptake capacity (V/sub max/) per unit root mass; nocturnal uptake of nutrients; and (only partially adaptive) reduced tissue concentrations of nutrients. We show that capital energy costs (in root growth) for acquiring nutrients can exceed direct or operational costs of internal metabolism (nitrate reduction, e.g.,); this has implications for the plant-controlled trade-off of NO/sub 3//sup -/-NH/sub 4//sup +/ - N/sub 2/ as N sources for legumes and other plant types. We outline needed further research and suggest guidelines for breeding plants for tolerating nutritional stresses; we also suggest that some measures of nutrient-use efficiency may be misleading. 6 references, 2 figures, 2 tables.
Date: August 1, 1984
Creator: Gutschick, V.P. & Kay, L.E.
System: The UNT Digital Library
Software for event oriented processing on multiprocessor systems (open access)

Software for event oriented processing on multiprocessor systems

Computing intensive problems that require the processing of numerous essentially independent events are natural customers for large scale multi-microprocessor systems. This paper describes the software required to support users with such problems in a multiprocessor environment. It is based on experience with and development work aimed at processing very large amounts of high energy physics data.
Date: August 1, 1984
Creator: Fischler, M.; Areti, H.; Biel, J.; Bracker, S.; Case, G.; Gaines, I. et al.
System: The UNT Digital Library
Developments of optical fast-gated imaging systems (open access)

Developments of optical fast-gated imaging systems

Several fast-gated imaging systems to measure ultra-fast single-transient data have been developed for time-resolved imaging of pulsed radiation sources. These systems were designed to achieve image recording times of 1 to 3 ms and dynamic ranges of >200:1 to produce large two-dimensional images (greater than or equal to 10/sup 4/ spatial points) of 1 to 2 ns exposure and small two-dimensional images (less than or equal to 200 spatial points) of less than or equal to 0.5 ns exposure. Both MCP intensified solid-state two-dimensional framing cameras and streak camera/solid-state camera systems were used; the framing camera system provides snap shots with high spatial resolution whereas the streak camera system provides for limited spatial points each with high temporal resolution. Applications of these systems include electron-beam, x-ray, gamma-ray, and neutron diagnostics. This report reviews the characteristics of the major components of fast-gated imaging systems developed at Lawrence Livermore National Laboratory. System performances are described in view of major experiments, and the diagnostic requirements of new experiments in atomic physics (x-ray lasers) and nuclear physics (fusion) are indicated.
Date: August 1984
Creator: Koehler, H. A. & Kotecki, D.
System: The UNT Digital Library
Momentum distributions in superfluid helium: bose condensate fraction (open access)

Momentum distributions in superfluid helium: bose condensate fraction

We have measured the momentum distributions in superfluid and normal Helium 4 at identical densities using inelastic neutron scattering as a function of temperature and density. At large enough momentum transfers Q the Impulse Approximation is valid and the single particle momentum distribution n(anti p) can be extracted from the inelastic scattering spectrum. Results are reported. (WHK)
Date: August 9, 1984
Creator: Sokol, P.E.; Simmons, R.O.; Price, D.L. & Hilleke, R.O.
System: The UNT Digital Library