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1.1-meter bore, 8-Tesla test facility

Description: The design and fabrication of a 1.1-m bore superconducting coil for an 8- T facility at Lawrence Livermore Laboratory are discussed. This facility will provide the backing field required for testing large multifilamentary Nb$sub 3$Sn coils as part of the superconductor development program at Livermore. The magnet measures 1.85 m o.d., is 1.5 m in length, and is solenoid wound in four separate modules. Total cold weight of the assembly is 18,000 Kg. A NbTi superconductor is used throughout with a gradation of current density within the magnet to provide complete cryostatic stability. The preliminary design of a large 3500-A multifilamentary Nb$sub 3$Sn insert magnet is also included. Together, the backing coil and insert magnets are designed to produce a 12-T central field in a 0.4m bore. The ''equal area'' theory of cryostatic stability is applied in the design of both magnet systems and is discussed in detail. A large open-mouth cryostat is used and measures 2 m in diameter and 3.7 m in length. Details of Dewar design and the refrigeration requirements are included. (auth)
Date: November 19, 1975
Creator: Nelson, R.; Cornish, D.; Zbasnik, J.; Sackett, S. & Taylor, C.

1.06 μm 150 psec laser damage study of diamond turned, diamond turned/ polished and polished metal mirrors

Description: Using a well characterized 1.06 μm 150 ps glass laser pulse the damage characteristics for diamond turned, diamond turned/ polished, and polished copper and silver mirrors less than 5 cm diameter were studied. Although most samples were tested with a normal angle of incidence, some were tested at 45$sup 0$ with different linear polarization showing an increase in damage threshold for S polarization. Different damage mechanisms observed will be discussed. Laser damage is related to residual surface influences of the fabrication process. First attempts to polish diamond turned surfaces resulted in a significant decrease in laser damage threshold. The importance of including the heat of fusion in the one dimensional heat analysis of the theoretical damage threshold and how close the samples came to the theoretical damage threshold is discussed. (auth)
Date: July 24, 1975
Creator: Saito, T. T.; Milam, D.; Baker, P. & Murphy, G.

4-inch sample recovery canisters, Test Model D series. Final report, September 1969--May 1970

Description: Six tests were conducted on 4-Inch Test Model D Closures to develop an improved closure for the redesigned Sandia Recovery Canister (SRC). The first three closures tested used variations of the high explosive (HE) design used on the previous Model B (Second) Series (P64283). The last three units tested used variations of the HE design used in the Midi Mist Event SRC.
Date: 1970
Creator: Goode, P. L. & Neff, G. W.

14'' x 17'' film recorder for computer-enhanced scans

Description: Physician acceptance of computer-enhanced radionuclide scan results, presented in the form of small Polaroid pictures, has been very limited for a number of subjective reasons. A new recorder was designed and constructed that presents the results of computer augmented scans through a medium that is quite familiar to doctors, the standard 14 in. x 17 in. x-ray film. (auth)
Date: January 1, 1976
Creator: Morris, A. C., Jr.; Barclay, T. R.; Akin, T. E.; Hansard, M. C.; Gibbs, W. D. & Modzelewski, C. U.

15 MeV neutron damage in Cu and Nb

Description: An investigation was made of high-energy neutron damage in Cu and Nb irradiated with approximately 15 MeV neutrons at the Oak Ridge Isochronous Cyclotron. The neutrons were generated by bombarding a thick Be target with 40- MeV deuterons resulting in a high energy neutron spectrum broadly peaked at 15 MeV. Single crystals of Cu and Nb were irradiated at room temperature to fluences of approximately 2 x 10$sup 17$ n/cm$sup 2$. The resulting loop-type defect clusters in the crystals were characterized using x-ray diffuse scattering and transmission electron microscopy. The cluster size distributions were found to be generally similar to those characteristic of fission neutron irradiations in these materials and no multiple clusters or sub-clusters were observed. Additional comparisons with fission reactor irradiations in Cu and Nb indicate that the retained displacement damage in these crystals is approximately 3 times greater for the high-energy neutrons than for an equivalent fluence of fission neutrons. This result is consistent with detailed damage energy calculations for the Be(d,n) neutron spectrum. (auth)
Date: January 1, 1975
Creator: Roberto, J. B.; Narayan, J. & Saltmarsh, M. J.

19 mm ballistic range: a potpourri of techniques and recipes

Description: The expansion of ballistic gun range facilities at LLL has introduced state-of-the-art diagnostic techniques to glovebox-enclosed ballistic guns systems. These enclosed ballistic ranges are designed for the study of one- dimensional shock phenomena in extremely toxic material such as plutonium. The extension of state-of-the-art phtographic and interferometric diagnostic systems to glovebox-enclosed gun systems introduces new design boundaries and performance criteria on optical and mechanical components. A technique for experimentally evaluating design proposals is illustrated, and several specific examples (such as, target alignment, collateral shrapnel damage, and soft recovery) are discussed. (auth)
Date: September 23, 1975
Creator: Carpluk, G.T.

100 mg $sup 251$Cf activation analysis facility at the Savannah River Laboratory

Description: The $sup 252$Cf Activation Analysis Facility at the Savannah River Laboratory (SRL) is used routinely for multielement analyses of a wide variety of solid and liquid samples (e.g., metal alloys, fly ash and other airborne particles, rocks, and aqueous and nonaqueous solutions). An automated absolute activation analysis technique, developed to use neutron transport codes to calculate multienergy group neutron spectra and fluxes, converts counting data directly into elemental concentrations expressed in parts per million. The facility contains four sources of $sup 252$Cf totaling slightly over 100 mg. A pneumatic ''rabbit'' system permits automatic irradiation/decay/counting regimes to be performed unattended on up to 100 samples. Detection sensitivities of less than or equal to 400 ppb natural uranium and less than or equal to 0.5 nCi/g for $sup 239$Pu are observed. Detection limits for over 65 elements have been determined. Over 40 elements are detectable at the one part per million level or less. Overall accuracies of +- 10 percent are observed for most elements. (auth)
Date: January 1, 1975
Creator: MacMurdo, K.W. & Bowman, W.W.

120 kA pulsed dc power system with computerized thyristor triggering

Description: A pulsed dc power system provides 120 kA excitation current for the ORMAK toroidal field coils. A drive potential of 1000 volts brings the coils up to full current in about 0.5 seconds. Constant current is maintained for 0.25 seconds, then approximately 20 x 10$sup 6$ joules of stored energy is dumped in a free-wheeling diode and resistance network. The power system contains 8 each, 30 kA, 500 V thyristor controlled dc power modules in a series/parallel combination. A control computer generates thyristor trigger pulses in a programmed sequence as required for the desired duty cycle. A feedback network including current sensing and computer software permits trigger timing adjustments as necessary for constant current operation. (auth)
Date: January 1, 1975
Creator: Mosko, S.W.; Bates, D.D.; Bigelow, R.R.; Cottongim, E.K.; Pipes, E.W. & Sueker, K.

200-GeV proton-proton elastic scattering at high transverse momentum

Description: This is a proposal to study p-p elastic scattering at the highest possible P{sub {perpendicular}}{sup 2} at NAL, using a CH{sub 2} or H{sub 2} target placed directly in the extracted beam and a double arm spectrometer. We expect to be able to set an upper limit at the level d{sigma}/dt/d{sigma}/dt{sub t=0} {approx} 10{sup -14}. This would be sufficient to determine if there are exactly three regions in the p-p interaction with considerable precision.
Date: June 1, 1970
Creator: Ratner, L.G.; /Argonne; Krisch, A.D.; Roberts, J.B.; Terwilliger, K.M. & U., /Michigan

200 kW, 800 MHz transmitter system for lower hybrid heating

Description: This paper describes a new rf heating system which has just been completed and is now operational on the ATC machine. The system utilizes four UHF TV klystrons to generate at least 200 kW of power at a frequency of 800 MHz. Pulse widths can be varied from 20 $mu$sec up to 20 msec. A radar type floating deck modulator along with photo-optical transmitting and receiving devices have been incorporated into the system to provide the pulse fidelity and versatility which characterizes this equipment. Modular construction was emphasized in the design, when possible, to reduce maintenance and down time in the advent of component falilure. Hybrid combining techniques are utilized in order to provide two 100 kW feeds into the machine. (auth)
Date: January 1, 1975
Creator: Deitz, A.

A 218 neutron group master cross section library for criticality safety studies

Description: The AMPX system was used to generate a P$sub 3$ 218 neutron group master cross-section library from ENDF/B-IV data for the fuel, structural, and neutron- absorbing materials tabulated. The library is the data base for the generation of broad-group cross sections for shipping cask calculations and other criticality safety analyses using codes such as KENO and ANISN. Selection of the fine-group energy structure for the 3-eV to 20-MeV energy range included consideration of the resonance structure of prominent nuclei, the thresholds of important reactions, and the fission spectra. For 10$sup -5$ less than or equal to E/sub n/ less than 3 eV, 78 closely spaced thermal groups were chosen to examine the effects of low-energy resonances and thermal-neutron upscatter. Distribution of the 218 groups within the Hansen-Roach 16-group boundaries is shown. Adequacy of the group structure and validity of selected data sets from the library were tested by P$sub 3$S$sub 8$ XSDRNPM calculations of k-eff for two benchmark critical experiments; first, the 4.9 percent-enriched UO$sub 2$F$sub 2$- H$sub 2$O solution critical sphere experiment of Johnson and Cronin was analyzed, and, second, the 93.2 percent-enriched UO$sub 2$F$sub 2$-H$sub 2$O solution critical sphere experiment of Fox was analyzed. (auth)
Date: January 1, 1975
Creator: Ford, W.E. III; Westfall, R.M. & Webster, C.C.

325-B FACILITY

Description: Due to the continuing high air sample results over the past six months, a thorough review of conditions and procedures was felt necessary for 325-B facility. A complete survey of the facility was made, looking for possible or definite problems. A discussion about procedures and conditions was held with all Radiation Monitoring personnel involved with the facility. The following items we felt needed attention to improve the working environment for the personnel in the facility. 1. Recommend glovebox be decontaminated and gloves changed to reduce dose rates. 2. Repair fume hood for proper airflow. 3. Move slurp jug inside fume hood and provide lead shielding. 4. Change storage of samples outside of cells to reduce dose rates. 5. Recommend contaminated waste from cells be bagged when removed through transfer tray. 6. Recommend fume hoods be installed at cell transfer trays. During a recent house cleaning, personnel in 325-B took action to correct items number 1 through 5, which leaves item number 6 to be considered. The need for fume hoods is based on high air sample results. These fume hoods would be very helpful in the unpackaging of contaminated samples. The removal of samples from the cell requires good air flow due to contamination levels.
Date: February 1, 1971