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Workshop on photon activation therapy: proceedings

Description: This Workshop was held concurrently with an IAEA Research Coordination Meeting on Exploration of the Possibility of High-LET Radiation for Non-conventional Radiotherapy in Cancer. The Workshop on Photon Activation Therapy (PAT) was given as a special session on April 18, as it was thoght PAT might eventually be found to be attractive to developing countries, which is a major concern of the IAEA. An effort was made to bring together representatives of the various groups known to be actively work… more
Date: April 18, 1985
Creator: Fairchild, R.G. (ed.)
Partner: UNT Libraries Government Documents Department
open access

Silver isotopic anomalies in iron meteorites: cosmic-ray production and other possible sources

Description: The sources of excess /sup 107/Ag observed in iron meteorites by Kaiser, Kelly, and Wasserburg (1980) are examined, with emphasis on the reactions of cosmic-ray particles with palladium. The cross sections for the production of the silver isotopes from palladium by energetic cosmic-ray particles are evaluated or estimated and used to calculate spallogenic production rates relative to that of /sup 53/Mn from iron. The upper limit for the production rate of excess /sup 107/Ag by galactic-cosmic-r… more
Date: April 18, 1980
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department
open access

General purpose computers in real time

Description: I see three main trends in the use of general purpose computers in real time. The first is more processing power. The second is the use of higher speed interconnects between computers (allowing more data to be delivered to the processors). The third is the use of larger programs running in the computers. Although there is still work that needs to be done, I believe that all indications are that the online need for general purpose computers should be available for the SCC and LHC machines. 2 fig… more
Date: September 18, 1989
Creator: Biel, J.R.
Partner: UNT Libraries Government Documents Department
open access

Summary of S = 0 dibaryon resonances and candidates

Description: Experimental data concerning S = O dibaryon resonances are reviewed, with an emphasis on the nucleon-nucelon system. Structures observed in the ..gamma..d channel, the ..pi..d elastic scattering, pp ..-->.. ..pi..d channel, and other channels are discussed. Experimental data are compared with various theories. The short-range forces can be represented by dibaryon resonances. Further measurements to clarify the understanding of dibaryons are also discussed. 53 refs., 24 figs.
Date: April 18, 1985
Creator: Yokosawa, A.
Partner: UNT Libraries Government Documents Department
open access

Hybrid Simulations With Dynamical Quarks: Spectra, Screening and Thermodynamics

Description: We summarize simulations made by the Argonne/University of Illinois group using the Hybrid algorithm to include dynamical staggered fermions. Recent work on the mass spectrum and screening effects due to the inclusion of four light flavors of dynamical quarks is presented. We also present a brief overview of what we have learned about the finite temperature chiral phase transition. 5 refs., 4 figs., 1 tab.
Date: November 18, 1987
Creator: Sinclair, D. K.
Partner: UNT Libraries Government Documents Department
open access

TSTA compound cryopump

Description: The Tritium System Test Assembly (TSTA), at the Los Alamos Scientific Laboratory, is intended to demonstrate realistic fuel supply and cleanup scenarios for future fusion reactors. The vacuum pumps must be capable of handling large quantities of reactor exhaust gases consisting largely of mixtures of hydrogen and helium isotopes. Cryocondensing pumps will not pump helium at 4.2 K; while cryosorption pumps using molecular sieves or charcoal have good helium pumping speed, the adsorbent clogs wit… more
Date: August 18, 1980
Creator: Batzer, T. H.; Patrick, R. E. & Call, W. R.
Partner: UNT Libraries Government Documents Department
open access

Availability of enriched stable isotopes: present status and future prospects

Description: The Electromagnetic Isotope Enrichment Facility (EMIEF) is currently used to produce 225 enriched stable isotopes of 50 elements. Among these are included most of the known elements with stable isotopes except for the noble gases, certain light elements, monisotopic elements, etc. The EMIEF can also be used to produce enriched samples of radioactive species, most notably the isotopes of uranium and plutonium. These enriched materials are placed in either the Sales Inventory of in the Research M… more
Date: September 18, 1986
Creator: Hoff, R.W.
Partner: UNT Libraries Government Documents Department
open access

Near-real-time actinide concentrations via energy dispersive XRFA for process control and material accountability

Description: A Co-57 based XRFA system has been installed on-line at ICPP to monitor uranium concentrations after first cycle decontamination. A small, medium, or large collimator is used to restrict fission product (fp) background count rates. Using two 50 mCi sources, 1 gU/1 can be measured to +-2% in 10 min with the medium collimator. A computer-based MCA runs the system automatically, controls an insertable U foil (allows calibration anytime) and an automatic W shutter (permits removal of fp background)… more
Date: November 18, 1983
Creator: Camp, D. C.; Ruhter, W. D.; Johnson, C. E. & Piper, T. C.
Partner: UNT Libraries Government Documents Department
open access

Coatings for laser fusion

Description: Optical coatings are used in lasers systems for fusion research to control beam propagation and reduce surface reflection losses. The performance of coatings is important in the design, reliability, energy output, and cost of the laser systems. Significant developments in coating technology are required for future lasers for fusion research and eventual power reactors.
Date: December 18, 1981
Creator: Lowdermilk, W.H.
Partner: UNT Libraries Government Documents Department
open access

Evolution of the mirror machine

Description: The history of the magnetic-mirror approach to a fusion reactor is primarily the history of our understanding and control of several crucial physics issues, coupled with progress in the technology of heating and confining a reacting plasma. The basic requirement of an MHD-stable plasma equilibrium was achieved following the early introduction of minimum-B multipolar magnetic fields. In refined form, the same magnetic-well principle carries over to our present experiments and to reactor designs.… more
Date: August 18, 1983
Creator: Damm, C. C.
Partner: UNT Libraries Government Documents Department
open access

Shock Hugoniot measurements on Ta to 0. 78 TPa

Description: Symmetric impact shock Hugoniot measurements have been made on Ta with an electrically exploded foil gun system. The results obtained to date for the Hugoniot of Ta cover the range 0.19 to 0.78 TPa (impact velocities from 4.0 to 9.7 km/s) and agree with data obtained by other researchers to within 2.7% rms. Recent improvements in the system include electromagnetic shielding of impactor and target, continuous measurement of impactor velocity with a Fabry-Perot interferometer and computer-aided a… more
Date: August 18, 1983
Creator: Froeschner, K. E.; Lee, R. S.; Chau, H. H. & Weingart, R. C.
Partner: UNT Libraries Government Documents Department
open access

Extension of the method of the small angle approximation: open detector

Description: We use the radiative transfer equation to study the multiple scattering undergone by a laser beam propagating through a turbid medium. During the propagation, we view the beam as first scattering into a narrow forward cone, and then into a diffuse pattern. To describe this process, we propose a systematic and practical method to combine the small angle approximation with the diffusion approximation. The method works when the scattering cross-section describing scattering from aerosols can be wr… more
Date: August 18, 1986
Creator: Chitanvis, S.M. & Gerstl, S.A.W.
Partner: UNT Libraries Government Documents Department
open access

Review of 1064-nm damage tests of electron-beam deposited Ta/sub 2/O/sub 5//SiO/sub 2/ antireflection coatings

Description: Damage tests of Ta/sub 2/O/sub 5//SiO/sub 2/ antireflection films deposited under a variety of conditions showed that thresholds of films deposited at 175/sup 0/C were greater than thresholds of films deposited at either 250/sup 0/C or 325/sup 0/C. Deposition at high rate and low oxygen pressure produced highly absorptive films with low thresholds. Thresholds did not correlate with film reflectivity or net stress in the films, and correlated with film absorption only when the film absorption wa… more
Date: December 18, 1981
Creator: Milam, D.; Rainer, F.; Lowdermilk, W.H.; Swain, J.E.; Carniglia, C.K. & Hart, T.T.
Partner: UNT Libraries Government Documents Department
open access

Coupling between plastic scintillators and light fibers for remote detection of x-rays

Description: Plastic scintillators can be coupled to light fibers to make small, simple, and inexpensive x-ray detectors. These detectors have been developed for use at the Nevada Test Site (NTS) for the remote detection of x-rays. Light produced in the scintillator can be transmitted by the fiber for several hundred meters to a photodetector, which is usually a streak camera or a photomultiplier tube. The use of a streak camera allows many channels to be recorded simultaneously. A parameter study has been … more
Date: July 18, 1985
Creator: Perry, T.S. & Molitoris, J.J.
Partner: UNT Libraries Government Documents Department
open access

Improved performance of the ATA injector

Description: During the last year we re-configured the ATA injector to accommodate field emission cathodes. The injector is now run as a diode machine with a 7 cm radius cathode, an A-K gap of 12.9 cm and a field stress of 190 kV/cm. The advantage of using field emission cathodes is we have increased the injector brightness by a factor of ten above the level we were able to reach using the low density plasma cathodes.
Date: June 18, 1985
Creator: Weir, J.T.; Caporaso, G.J. & Prono, D.S.
Partner: UNT Libraries Government Documents Department
open access

Correlation of macroscopic material properties with microscopic nuclear data

Description: Two primary irradiation-induced changes occur during neutron irradiation: the displacement of atoms forming crystal defects and the transmutation of atoms into either gaseous or solid products. The material scientist studying irradiation damage to material by fusion-produced neutrons is faced with several questions: Is the nature of high-energy (14-MeV) displacement damage the same as or different from that caused by fission neutrons (< 2 MeV). How do the high helium concentrations expected in … more
Date: December 18, 1981
Creator: Simons, R.L.
Partner: UNT Libraries Government Documents Department
open access

The glycophorin A assay for somatic cell mutations in humans

Description: In this report we briefly review our past experience and some new developments with the GPA assay. Particular emphasis will be placed on two areas that affect the utility of the GPA assay for human population monitoring. The first is our efforts to simplify the GPA assay to make it more generally available for large population studies. The second is to begin to understand some of the characteristics of human hemopoiesis which affect the accumulation and expression of mutant phenotype cells. 11 … more
Date: August 18, 1989
Creator: Langlois, R.G.; Bigbee, W.L. & Jensen, R.H.
Partner: UNT Libraries Government Documents Department
open access

Model based controls and the AGS booster controls system architecture

Description: The Heavy Ion Transfer Line used to inject heavy ions created at the Tandem Van de Graaff into the Alternating Gradient Synchrotron (AGS) is briefly discussed, particularly as regards its control system. (LEW)
Date: August 18, 1987
Creator: Casella, R.A.
Partner: UNT Libraries Government Documents Department
open access

A microwave power driver for linac colliders: Gigatron

Description: The gigatron is a new rf amplifier tube designed for linac collider applications. Three design features permit extension of the lasertron concept to very high frequencies. First, a gated field-emitter array is employed for the modulated cathode. Second, a ribbon beam geometry mitigates space charge depression and facilitates efficient output coupling. Third, a traveling wave output coupler is used to obtain optimum coupling to the ribbon beam. This paper describes recent developments in the gig… more
Date: November 18, 1988
Creator: Bizek, H.M.; Elliott, S.M.; McIntyre, P.M.; Nassiri, A.; Popovic, M.B.; Raparia, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Getting maximum information from incomplete data on B yields charmonium-K sub S decays

Description: Tests of CP violation using B decays into CP eigenstates can be improved by using events normally rejected because of incomplete information. A search for lepton asymmetry in decays {Upsilon}(4S) {yields} B + {bar B} {yields} (K{sub S} + J/{psi}) + (lepton {sup {plus minus}} + X) can be improved by including other (c{bar c})K{sub S} events where the (c{bar c}) pair is not bound in a J/{psi} but in some other state like {psi}{prime} or {eta}{sub c} and where the lepton asymmetry is predicted to … more
Date: September 18, 1989
Creator: Lipkin, Harry J.
Partner: UNT Libraries Government Documents Department
open access

Environmental impact of uranium mining and milling: an American view

Description: The radiation dose rates to man from uranium milling activities are discussed. The sources of radiation, the radioisotopes involved, and the environmental exposure pathways are described. Risks of cancer to exposed individuals are presented and recommendations made for mitigation of contamination. (ACR)
Date: August 18, 1981
Creator: Momeni, M. H.
Partner: UNT Libraries Government Documents Department
open access

Super-collider: progress, options and physics

Description: The Superconducting Super Collider (SSC) has been given high priority by the high energy physics community. Various aspects of the project - physics motivation, accelerator design, siting considerations - are discussed here. The project is moving rapidly and parts of this discussion have been updated to reflect the vast amount of work that has gone into the SSC since the conference.
Date: October 18, 1984
Creator: Diebold, R.
Partner: UNT Libraries Government Documents Department
open access

Welding stainless steels for structures operating at liquid helium temperature

Description: Superconducting magnets for fusion energy reactors require massive monolithic stainless steel weldments which must operate at extremely low temperatures under stresses approaching 100 ksi (700 MPa). A three-year study was conducted to determine the feasibility of producing heavy-section welds having usable levels of strength and toughness at 4.2/sup 0/K for fabrication of these structures in Type 304LN plate. Seven welding processes were evaluated. Test weldments in full-thickness plate were ma… more
Date: April 18, 1980
Creator: Witherell, C.E.
Partner: UNT Libraries Government Documents Department
open access

Nova laser assurance-management system

Description: In a well managed project, Quality Assurance is an integral part of the management activities performed on a daily basis. Management assures successful performance within budget and on schedule by using all the good business, scientific, engineering, quality assurance, and safety practices available. Quality assurance and safety practices employed on Nova are put in perspective by integrating them into the overall function of good project management. The Nova assurance management system was dev… more
Date: July 18, 1983
Creator: Levy, A.J.
Partner: UNT Libraries Government Documents Department
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