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Prospects for physics at e/sup +/e/sup -/ linear colliders (open access)

Prospects for physics at e/sup +/e/sup -/ linear colliders

The present thinking on high-energy e/sup /plus//e/sup /minus// linear colliders is reviewed, stressing those points that have consequences for detector design and physics analyses. Detector requirements are discussed. Experimental aspects of the physics that can be done at these colliders are discussed: first the general physics environment, then a standard process, W/sup /plus// W/sup /minus// detection, and finally four examples of the discovery potential of these colliders /emdash/ heavy quarks, heavy leptons, standard Higgs bosons, and charged Higgs bosons. The conclusions of this study will be stated. 23 refs., 40 figs.
Date: March 1, 1988
Creator: Feldman, G. J.
System: The UNT Digital Library
Di-leptons at the Bevalac (open access)

Di-leptons at the Bevalac

Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate that hypothesis. (LEN)
Date: March 1, 1988
Creator: Matis, H.S.
System: The UNT Digital Library
Compatibility testing of vitrified waste forms (open access)

Compatibility testing of vitrified waste forms

An experimental program to evaluate candidate metals for use in the fabrication of canisters for long-term storage of vitrified radioactive wastes is described. The long-term compatibility of the candidate metal both with the contained vitrified radioactive waste and with the external environments expected in possible final storage locations will be determined. These tests involve heating combinations of waste forms and canister metals in intimate contact for up to 50,000 hr to accelerate any reactions that occur.
Date: March 6, 1978
Creator: Rankin, W.N.
System: The UNT Digital Library
Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness (open access)

Measurements of the dependence of damage thresholds on laser wavelength, pulse duration and film thickness

Results of three experiments will be described. We used 351-nm and 355-nm pulses with durations of 0.6, 1, 5 and 9 ns measure thresholds for a variety of anti-reflectance and high reflectance coatings. The functional form t/sup m/, with t the pulse duration, was used to scale fluence thresholds measured at 0.6 ns to those measured at 9.0 ns. Values of the coefficient m ranged from 0.10 to 0.51. The average value was 0.30. In the second experiment, we measured thresholds at 1064 nm, 527 nm and 355 nm for single-frequency high reflectance ZrO/sub 2//SiO/sub 2/ coatings. Coatings for all three frequencies were deposited simultaneously by use of masks in the coating chamber. Thresholds varied from 2 to 4 J/cm/sup 2/ at 355 nm to 7 to 10 J/cm/sup 2/ at 1064 nm. The third experiment measured thresholds at 355 nm for antireflection coatings made with layer thicknesses varying from greater than one wavelength to less than a quarterwavelength. A significant variation of threshold with coating thickness was not observed, but the median thresholds increased slightly as coating thickness increased.
Date: March 1, 1984
Creator: Rainer, F.; Vercimak, C.L.; Milam, D.; Carniglia, C.K. & Tuttle Hart, T.
System: The UNT Digital Library
Irradiation experiment for lithium ceramics (open access)

Irradiation experiment for lithium ceramics

Solid breeder materials are required in D-T fusion reactor blankets to convert fusion neutrons to tritium and thermal energy while providing some neutron shielding for the magnets. Lithium compounds such as Li/sub 2/O, LiAlO/sub 2/, Li/sub 4/SiO/sub 4/ and Li/sub 2/ZrO/sub 3/ have been proposed as solid breeder materials. Tritium is necessary to maintain the fuel supply for the D-T fusion reaction. No high burnup irradiation performance data is available for these materials in a neutron environment prototypic of the fusion blanket. The FUBR Experiment in EBR-II has been designed and built to evaluate the irradiation performance of these materials.
Date: March 1, 1982
Creator: Hollenberg, G.W.
System: The UNT Digital Library
Estimates of SASE power in the short wavelength region (open access)

Estimates of SASE power in the short wavelength region

Given a sufficiently bright electron beam, the self-amplified-spontaneous emission (SASE) can provide gigawatts of short wavelength coherent radiation. The advantages of SASE approach are that is requires neither optical cavity nor an imput seed laser. In this note, we estimate the peak power performance of SASE for wavelengths shorter than 1000 {Angstrom}. At each wavelength, we calculate the saturated power from a uniform parameter undulator and the enhanced power from a tapered undulator. The method described here is an adaptation of that discussed by L.H. Yu, who discussed the harmonic generation scheme with seeded laser, to the case of SASE.
Date: March 1, 1992
Creator: Kim, Kwang-Je.
System: The UNT Digital Library
Geothermal waste treatment biotechnology: Progress and advantages to the utilities (open access)

Geothermal waste treatment biotechnology: Progress and advantages to the utilities

Development of biotechnology for treatment of geothermal residual waste is aimed at the application of low-cost biochemical processes for the surface treatment and disposal of residual geothermal sludges. These processes, in addition to the lowering of disposal cost, are designed to be environmentally acceptable. Recent studies at Brookhaven National Laboratory (BNL) have shown that optimization of several process variables results in fast rates (<24h) of metal removal from residual sludges at acidic pH ({minus}1--2). Optimization of the process variables also enables the removal of radioactive isotopes. In addition, the aqueous phase produced during the bioprocessing which contains solubilized metals can be further treated in a manner which precipitates out the metals and renders the aqueous effluent toxic metal free. In this paper, the various process options will be discussed in terms of biotreatment variables. Chemical composition before and after biotreatment will also be discussed in terms of long-range effects, quality assurance and potential disposal costs.
Date: March 1, 1992
Creator: Premuzic, E.T.; Lin, M.S. & Jin, J.
System: The UNT Digital Library
Shear alfven resonances in Tokapole II (open access)

Shear alfven resonances in Tokapole II

It has been suggested that efficient heating can occur by coupling energy through the shear Alfven resonance that is predicted to occur at particular locations within inhomogeneous plasmas. This heating mechanism should be applicable to tokamaks; however, the existence of the resonances in tokamaks has not yet been established experimentally. We present here direct observations of localized enhancement in the driven wave magnetic field which are compatible with theoretical predictions for the shear Alfven resonance in tokamak geometry. These resonance studies at low absorbed power will be followed by higher power heating (approx. 1 MW) presently being developed.
Date: March 1, 1982
Creator: Witherspoon, F.D.; Prager, S.C. & Sprott, J.C.
System: The UNT Digital Library
Field characterization and personal dosimetry at a high energy ion accelerator (open access)

Field characterization and personal dosimetry at a high energy ion accelerator

The response of a variety of dosimeters was evaluated in the radiation field outside the shielding of the Lawrence Berkeley Laboratory Bevalac Biomedical Facility. The primary beam was 580 MeV/center dot/A neon ions, incident upon a 30.5-cm polyethylene cube. The field was characterized by a neutron spectrometer consisting of Bonner spheres and other detectors and by estimates of charged particle fluences in NTA film and in the Berklet spectrometer. The responses of American Acrylics CR-39 track-etch plastic detectors and AECL (Canada) type BD-100 Bubble Detectors were compared to those of NTA film, Andersson-Braun remmeter and recombination-chamber results as well as to reference dose equivalents based upon the unfolded neutron spectrum. Evaluations of these dosimeters are discussed. 7 refs., 4 figs.
Date: March 1, 1988
Creator: Greenhouse, N. A.; Busick, D. D.; de Castro, T. M.; Elwyn, A. J.; Hankins, D. E.; Ipe, N. E et al.
System: The UNT Digital Library
Least cost planning from a customer's perspective (open access)

Least cost planning from a customer's perspective

In this paper, I offer some thoughts about least cost planning, not from the perspective of the regulator or utility, but from the perspective of a residential customer. The problem that I address is, as a homeowner in northern Virginia, I am about to make a long term fuel choice for my household, where the options include, natural gas, electricity and fuel oil. An additional choice is the energy efficiency capital investment in my home that could decrease my monthly fuel costs. My decision process, hopefully as a rational consumer, offers implications about the efficiency of various services provided by all three fuel suppliers, including the local natural gas distribution companies (LDC).
Date: March 2, 1992
Creator: Sutherland, R.J.
System: The UNT Digital Library
Computer controlled cartridge case quality assurance inspection system (open access)

Computer controlled cartridge case quality assurance inspection system

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Date: March 1, 1975
Creator: Compton, M R & Erickson, M D
System: The UNT Digital Library
Nuclear mass formula with a neutron skin degree of freedom and finite-range model for the surface energy (open access)

Nuclear mass formula with a neutron skin degree of freedom and finite-range model for the surface energy

We study the possibility of extending the model used by Moeller and Nix in 1980 to calculate nuclear masses and fission barriers for nuclei throughout the periodic system, to describe compressibility effects and the existence of a neutron skin. 9 references. (WHK)
Date: March 1, 1984
Creator: Moeller, P. & Myers, W.D.
System: The UNT Digital Library
Detection of charged particles in thick hydrogenated amorphous silicon layers (open access)

Detection of charged particles in thick hydrogenated amorphous silicon layers

We show our results in detecting particles of various linear energy transfer, including minimum ionizing electrons from a Sr-90 source with 5 to 12 micron thick n-i-p and p-i-n diodes. We measured W ( average energy to produce one electron-hole pair) using 17keV filtered xray pulses with a result W = 6.0 /+-/ 0.2eV. This is consistent with the expected value for a semiconductor with band gap of 1.7 to 1.9eV. With heavily ionizing particles such as 6 MeV alphas and 1 to 2 MeV protons, there was some loss of signal due to recombination in the particle track. The minimum ionizing electrons showed no sign of recombination. Applications to pixel and strip detectors for physics experiments and medical imaging will be discussed. 7 refs., 8 figs.
Date: March 1, 1988
Creator: Fujieda, I.; Cho, G.; Kaplan, S. N.; Perez-Mendez, V.; Qureshi, S.; Ward, W. et al.
System: The UNT Digital Library
Semiclassical methods in chemical dynamics (open access)

Semiclassical methods in chemical dynamics

A general semiclassical (multidimensional WKB-type) approximation to quantum mechanics is reviewed. The principal feature of the approach is that it is able to incorporate the exact classical mechanics of the system and also the quantum principle of superposition. Applications to inelastic and reactive scattering, and to statistical mechanics and reaction rates are discussed. 13 refs.
Date: March 1, 1985
Creator: Miller, W. H.
System: The UNT Digital Library
Studies of evaporative and conventional cooling of an energy conserving California house (open access)

Studies of evaporative and conventional cooling of an energy conserving California house

For cooling a Sacramento, California home, (1) higher thermostat settings, (2) insulation (3) ''solar control'' window shades, and (4) the use of an evaporative cooler in the place of a vapor compression cycle air conditioner are studied. A computer program TWOZONE is used to evaluate the effect on energy consumption and peak power. It is calculated that the peak cooling load can be reduced by a factor of 5 or more and the total energy by a factor of 20 or more.
Date: March 1, 1978
Creator: Gates, S.D.; Baughn, J. & Rosenfeld, A.H.
System: The UNT Digital Library
Capture reactions of /sup 40/Ca and /sup 48/Ca with targets of /sup 197/Au and /sup 208/Pb (open access)

Capture reactions of /sup 40/Ca and /sup 48/Ca with targets of /sup 197/Au and /sup 208/Pb

The reactions of /sup 40/Ca and /sup 48/Ca with targets of /sup 197/Au and /sup 208/Pb have been measured in the region from below the interaction barrier to about twice the barrier energy. The fission-like fragments were detected in a pair of position-sensitive, multi-wire proportional counters and were identified from measurements of position and time using two-body kinematics. In the region above the barrier the cross sections for capture are less than those given by the touching condition, indicating that an /open quotes/extra push/close quotes/ is required to induce capture. The observations for /sup 40/Ca and /sup 48/Ca show different fissilities for the onset of the extra push and indicate that charge equilibration may be an important factor governing capture reactions. Below the barrier the cross sections show an enhancement relative to the prediction for a one dimensional barrier. The enhancements are larger for /sup 40/Ca than for /sup 48/Ca (for both targets) and this is in qualitative agreement with predictions based on the coupling of the relative motion to low-lying collective states. Both above and below the barrier, we find that the change in the light partner, from /sup 48/Ca to /sup 40/Ca, has a larger effect on the …
Date: March 1, 1988
Creator: Stokstad, R.; Chan, Y.; Chavez, E.; Di Gregorio, D.; di Tada, M.; Gazes, S. et al.
System: The UNT Digital Library
An outdoor test facility for the large-scale production of microalgae (open access)

An outdoor test facility for the large-scale production of microalgae

The goal of the US Department of EnergySolar Energy Research Institute's Aquatic Species Program is to develop the technology base to produce liquid fuels from microalgae. This technology is being initially developed for the desert Southwest. As part of this program an outdoor test facility has been designed and constructed in Roswell, New Mexico. The site has a large existing infrastructure, a suitable climate, and abundant saline groundwater. This facility will be used to evaluate productivity of microalgae strains and conduct large-scale experiments to increase biomass productivity while decreasing production costs. Six 3-m/sup 2/ fiberglass raceways were constructed. Several microalgae strains were screened for growth, one of which had a short-term productivity rate of greater than 50 g dry wt m/sup /minus/2/ d/sup /minus/1/. Two large-scale, 0.1-ha raceways have also been built. These are being used to evaluate the performance trade-offs between low-cost earthen liners and higher cost plastic liners. A series of hydraulic measurements is also being carried out to evaluate future improved pond designs. Future plans include a 0.5-ha pond, which will be built in approximately 2 years to test a scaled-up system. This unique facility will be available to other researchers and industry for studies on microalgae …
Date: March 1, 1988
Creator: Johnson, D.A.; Weissman, J. & Goebel, R.
System: The UNT Digital Library
Polarization phenomena in projectile fragmentation process (open access)

Polarization phenomena in projectile fragmentation process

The nuclear spin polarization of beta-emitting fragments {sup 37}K and {sup 39} Ca has been measured at around the grazing angle of the {sup 40}Ca + Au collision at 106 MeV/u. Momentum dependence of the observed fragment polarization supports the idea that the origin of the polarization is the orbital angular momentum held by the fragment part of the projectile before the collision takes place. The sizable polarization of about 5% that was observed for the fragments will be a powerful tool for NMR study of the fragments.
Date: March 1, 1992
Creator: Matsuta, K.; Ozawa, A.; Nojiri, Y.; Minamisono, T.; Fukuda, M.; Kitagawa, A. et al.
System: The UNT Digital Library
Development and testing of an air quality model for Mexico City (open access)

Development and testing of an air quality model for Mexico City

Los Alamos National Laboratory and Instituto Mexicano del Petroleo have embarked on a joint study of options for improving air quality in Mexico City. The intent is to develop a modeling system which can address the behavior of pollutants in the region so that option for improving Mexico City air quality can be properly evaluated. In February of 1991, the project conducted a field program which yielded a variety of data which is being used to evaluate and improve the models. Normally the worst air quality for both primary and photochemical pollutants occurs in the winter Mexico City. During the field program, measurements included: (1) lidar measurements of aerosol transport and dispersion, (2) aircraft measurements of winds, turbulence, and chemical species aloft, (3) aircraft measurements of earth surface skin temperatures, and (4) tethersonde measurements of wind, temperature and ozone vertical profiles. A three-dimensional, prognostic, higher order turbulence meteorological model (HOTMAC) was modified to include an urban canopy and urban heat sources. HOTMAC is used to drive an Monte-Carlo kernel dispersion code (RAPTAD). HOTMAC also provides winds and mixing heights for the CIT photochemical model which was developed by investigators at the California Institute of Technology and Carnegie Mellon University.
Date: March 2, 1992
Creator: Williams, M. D.; Streit, G. (Los Alamos National Lab., NM (United States)); Cruz, X.; Ruiz, M.; Sosa, G. (Instituto Mexicano de Petroleo, Mexico City (Mexico)); Russell, A. G. et al.
System: The UNT Digital Library
Electron-positron physics at 1 TeV (open access)

Electron-positron physics at 1 TeV

We discuss the motivation for TeV e/sup +/ e/sup )minus/) linear colliders, some aspects of their design, and the experimental consequences that follow from the design. After a brief discussion of the general physics environment, we consider the discovery potential of these colliders by examining three sample processes: the detection of new heavy leptons, standard Higgs bosons, and charged Higgs bosons. 13 refs., 22 figs., 5 tabs.
Date: March 1, 1988
Creator: Feldman, G. J.
System: The UNT Digital Library
Cycle 7 outage experience. [Fast Flux Test Facility (FFTF)] (open access)

Cycle 7 outage experience. [Fast Flux Test Facility (FFTF)]

The scheduled 58-day refueling outage in preparation for the seventh operating cycle of the Fast Flux Test Facility (FFTF) was successfully completed three days ahead of schedule. The planning and execution of the outage was greatly aided by Project/2 automated scheduling capabilities. For example, the use of ''maintenance windows'' and resource loading capabilities was particularly effective. The value of the planning process was demonstrated by the smooth transition into the outage phase after an early shutdown and set the stage for our best outage to date.
Date: March 1, 1986
Creator: Gadeken, A.D.
System: The UNT Digital Library
Introduction to human factors (open access)

Introduction to human factors

Some background is given on the field of human factors. The nature of problems with current human/computer interfaces is discussed, some costs are identified, ideal attributes of graceful system interfaces are outlined, and some reasons are indicated why it's not easy to fix the problems. (LEW)
Date: March 1, 1988
Creator: Winters, J. M.
System: The UNT Digital Library
Comparison of aerosol behavior during sodium fires in CSTF with the HAA-3B code. [LMFBR] (open access)

Comparison of aerosol behavior during sodium fires in CSTF with the HAA-3B code. [LMFBR]

Four large-scale tests using sodium fire aerosol sources have been carried out in the Containment System Test Facility (CSTF). Two of the tests employed pool fires and two used spray fires as the aerosol source. Because the CSTF containment vessel is approximately half-scale (20.3 m in height) of a typical reactor building, the CSTF results have provided a large-scale proof test of the HAA-3B Code. For the two pool fire tests, the measured and predicted airborne concentrations were in good agreement when the aerosol source term was based on post-test measurements of aerosol formation, accounting for water vapor uptake.
Date: March 1, 1980
Creator: Postma, A.K. & Owen, R.K.
System: The UNT Digital Library
Breakdown phenomena in high power klystrons (open access)

Breakdown phenomena in high power klystrons

In the course of developing new high peak power klystrons at SLAC, high electric fields in several regions of these devices have become an important source of vacuum breakdown phenomena. In addition, a renewed interest in breakdown phenomena for nanosecond pulse, multi-megavolt per centimeter fields has been sparked by recent R and D work in the area of gigawatt RF sources. The most important regions of electrical breakdown are in the output cavity gap area, the RF ceramic windows, and the gun ceramic insulator. The details of the observed breakdown in these regions, experiments performed to understand the phenomena and solutions found to alleviate the problems will be discussed. Recently experiments have been performed on a new prototype R and D klystron. Peak electric fields across the output cavity gaps of this klystron exceed 2 MV/cm. The effect of peak field duration (i.e. pulse width) on the onset of breakdown have been measured. The pulse widths varied from tens of nanoseconds to microseconds. Results from these experiments will be presented. The failure of ceramic RF windows due to multipactor and puncturing was an important problem to overcome in order that our high power klystrons would have a useful life expectancy. …
Date: March 1, 1988
Creator: Vlieks, A. E.; Allen, M. A.; Callin, R. S.; Fowkes, W. R.; Hoyt, E. W.; Lebacqz, J. V. et al.
System: The UNT Digital Library