15 Matching Results

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Heavy leptons at the SSC (open access)

Heavy leptons at the SSC

It is argued that detection of heavy leptons at the Superconducting Super Collider seems to be very difficult but perhaps not impossible. The feasibility is shown to depend critically upon the ability to identify events with W's decaying hadronically and missing transverse momentum. (LEW)
Date: December 15, 1987
Creator: Anderson, G. & Hinchliffe, I.
System: The UNT Digital Library
Production of eta mesons in e/sup +/e/sup -/ annihilations at. sqrt. s = 29 GeV (open access)

Production of eta mesons in e/sup +/e/sup -/ annihilations at. sqrt. s = 29 GeV

Data from e/sup +/e/sup -/ annihilations at 29 GeV have been used to measure the production and fragmentation of eta mesons. The signal is observed in the eta ..-->.. ..gamma gamma.. decay channel. The fragmentation function for p/sub eta/ > 1.5 GeV/c agrees well with the shapes predicted by both the Lund and Webber models. However, the mean multiplicity is measured to be < n/sub eta/ > = 0.37 +- 0.08 eta mesons per hadronic annihilation event, which is significantly lower than the values predicted by either model. 6 refs., 2 figs., 1 tab.
Date: June 15, 1987
Creator: Abachi, S.; Akerlof, C.; Baringer, P.; Blockus, D.; Brabson, B.; Brom, J.M. et al.
System: The UNT Digital Library
Use of the LLNL 40 kV electric gun to study the shock response of 21-6-9 stainless steel (open access)

Use of the LLNL 40 kV electric gun to study the shock response of 21-6-9 stainless steel

Exploding foil-flyer plate (''electric gun'') methods have been used to shock 21-6-9 stainless steel over a wide range of shock pulse amplitudes (20 to 53 GPa) and durations (10 to 70 ns). Dislocation generation and twinning have been studied in recovered specimens with the results providing support for the concept of finite rate plastic processes. 24 refs., 6 figs., 1 tab.
Date: July 15, 1987
Creator: Brusso, J. A.; Mikkola, D. E.; Bloom, G.; Lee, R. S. & Von Holle, W.
System: The UNT Digital Library
Comparisons of power transfer functions and flow transfer functions (open access)

Comparisons of power transfer functions and flow transfer functions

Transfer functions may be used to calculate component feedbacks or temperature increments by convolution of the transfer function with the appropriate fractional change in system-quantity. Power-change transfer functions have been reported. The corresponding flow transfer functions for this case, and comparison with the power transfer functions, are reported here. Results of feedback simulation of ramped flow transients using flow transfer functions are also described.
Date: November 15, 1987
Creator: Grimm, K. N. & Meneghetti, D.
System: The UNT Digital Library
The stability of free-electron lasers against filamentation (open access)

The stability of free-electron lasers against filamentation

In inertial confinement fusion (ICF) experiments, the high electromagnetic fields propagating through a relatively dense plasma can result in a transverse instability, causing the matter and light to form filaments oriented parallel to the light beam. We examine whether a similar instability exists in the electron beam of a free-electron laser, where such an instability could interfere with the transfer of beam kinetic energy into optical wave energy. We heuristically examine the instability in a relativistic beam through which an intense laser beam is propagating. We ignore the FEL effects. We estimate how the altered index of refraction in an FEL affects the dispersion relation. Finally, we estimate the effect that the instability could have on the phase coherence of a particle as it transits an FEL. 10 refs., 2 tabs.
Date: September 15, 1987
Creator: Barnard, J. J.; Scharlemann, E. T. & Yu, S. S.
System: The UNT Digital Library
Calculation of radial and vertical forces on the CIT 1. 75 m vacuum vessel for several TSC disruption scenarios (open access)

Calculation of radial and vertical forces on the CIT 1. 75 m vacuum vessel for several TSC disruption scenarios

The report consists of viewgraphs. (WRF)
Date: September 15, 1987
Creator: Sayer, R.O.
System: The UNT Digital Library
Poloidal magnetics studies on swept divertor and internal coil issues. [Viewgraphs - strike points] (open access)

Poloidal magnetics studies on swept divertor and internal coil issues. [Viewgraphs - strike points]

This paper consists of viewgraphs on swept divertors and internal magnet coils for a Compact Ignition Tokamak design. The author concludes that poloidal field energy and volt-second considerations suggest a swept divertor scenario where the outboard strike point moves from small R to large R, while the inboard strike point moves from small Z to large Z. (LSP)
Date: September 15, 1987
Creator: Strickler, D. J.
System: The UNT Digital Library
Predictions for nuclear properties along the r-process path (open access)

Predictions for nuclear properties along the r-process path

The uniformity of different nuclear regions as a function of the number of valence protons and neutrons (counted from the nearest closed shell) has been exploited for the parameterization of calculations for nuclei far from stability within the IBA model. Predictions are given for low lying levels, E2 transition rates, and binding energies for nuclei in the r-process path in the A = 150 and A = 190 mass regions. 6 refs., 6 figs.
Date: October 15, 1987
Creator: Aprahamian, A.
System: The UNT Digital Library
Problems in modeling TF ripple loss of fast alphas from a tokamak reactor (open access)

Problems in modeling TF ripple loss of fast alphas from a tokamak reactor

The report consists of viewgraphs. Topics covered are (1) basic ripple processes, (2) simulations of combined processes, (3) modeling issues, (4) new physics problems, and (5) consequences for ETR/ITER. (WRF)
Date: June 15, 1987
Creator: Hively, L.M.
System: The UNT Digital Library
Dipole strength functions in the actinide mass region (open access)

Dipole strength functions in the actinide mass region

We have calculated a number of neutron- and photon-induced reactions for the actinide nuclei /sup 232/Th, /sup 238/U, and /sup 237/Np. By fitting average resonance capture (ARC) measurements and total neutron capture data, we deduced absolute dipole strength functions for /sup 233/Th and /sup 239/U. We have found that the M1/E1 ratio is the same as in the /sup 176/Lu case, but the total transition strength was larger by about 27%. 17 refs., 4 figs., 1 tab.
Date: July 15, 1987
Creator: Gardner, D. G.; Gardner, M. A. & Hoff, R. W.
System: The UNT Digital Library
Economics of Induction Linac Drivers for Radiation Sources (open access)

Economics of Induction Linac Drivers for Radiation Sources

Recent developments in high reliability components for linear induction accelerators (LIA) make possible the use of LIAs as large-scale, economical sources of radio-frequency (rf) power for many applications. One particularly attractive example of interest to high energy physicists is a ''two-beam accelerator'' version of a linear e/sup +/-e/sup -/ collider at TeV energies in which the LIA is configured as a monolithic relativistic klystron operating at 10 to 12 GHz. Another example of keen interest to the fusion community is the use of the LIA to drive a free-electron laser operating at 200 to 500 GHz for use in heating fusion plasma via electron resonance cyclotron heating. This paper briefly describes several potential uses of LIA radiation sources. It discusses the physical basis for scaling our present experience with LIAs to the operating characteristics applicable to large-scale sources of rf power and synchrotron radiation. 14 refs., 6 figs., 1 tab.
Date: June 15, 1987
Creator: Barletta, W. A.
System: The UNT Digital Library
High-Temperature Photochemistry and BAC-MP4 Studies of the Reaction Between Ground-State H Atoms and N2O (open access)

High-Temperature Photochemistry and BAC-MP4 Studies of the Reaction Between Ground-State H Atoms and N2O

Article on high-temperature photochemistry and BAC-MP4 studies of the reaction between ground-state H atoms and N2O.
Date: May 15, 1987
Creator: Marshall, Paul; Fontijn, A. (Arthur) & Melius, Carl F.
System: The UNT Digital Library
HTP kinetics studies of the reactions of O(2(3)Pj) atoms with H2 and D2 over wide temperature ranges (open access)

HTP kinetics studies of the reactions of O(2(3)Pj) atoms with H2 and D2 over wide temperature ranges

Article on HTP kinetics studies of the reaction of O(2(3)Pj) atoms with H2 and D2 over wide temperature ranges.
Date: December 15, 1987
Creator: Marshall, Paul & Fontijn, A. (Arthur)
System: The UNT Digital Library
L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions (open access)

L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions

Article discussing research on L- and M-shell x-ray production cross sections of Nd, Gd, Ho, Yb, Au, and Pb by 25-MeV carbon and 32-MeV oxygen ions.
Date: October 15, 1987
Creator: Andrews, M. C.; McDaniel, Floyd Del. (Floyd Delbert), 1942-; Duggan, Jerome L.; Miller, P. D.; Pepmiller, P. L.; Krause, H. F. et al.
System: The UNT Digital Library
Hydrogen speciation in hydrated layers on nuclear waste glass (open access)

Hydrogen speciation in hydrated layers on nuclear waste glass

The hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90{sup 0}C (all glasses) or hydrated in a vapor-saturated atmosphere at 202{sup 0}C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. Molecular water was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 {mu}m layer on SRL-131 glass formed by leaching at 90{sup 0}C …
Date: January 15, 1987
Creator: Aines, R. D.; Weed, H. C. & Bates, J. K.
System: The UNT Digital Library