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Geology of the Quartz Creek Pegmatite District, Gunnison County, Colorado

Description: Report discussing the geology of the Quartz Creek pegmatite district of Gunnison County, Colorado. "The Quartz Creek pegmatite district includes an area of about 29 square miles in the vicinity of Quartz Creek in Gunnison County, Colorado. This area contains 1,803 pegmatites that are intruded into pre-Cambrian rocks."
Date: April 1952
Creator: Staatz, Mortimer H. & Trites, Albert F.
Partner: UNT Libraries Government Documents Department

Low-Intensity Nonlinear Spectral Effects in Compton Scattering

Description: Nonlinear effects are known to occur in Compton scattering light sources, when the laser normalized 4-potential, A = e{radical}-A{sub {mu}}A{sup {mu}}/m{sub 0}c approaches unity. In this letter, it is shown that nonlinear spectral features can appear at arbitrarily low values of A, if the fractional bandwidth of the laser pulse, {Delta}{phi}{sup -1}, is sufficiently small to satisfy A{sup 2} {Delta}{phi} {approx_equal} 1. A three dimensional analysis, based on a local plane-wave, slow-varying envelope approximation, enables the study of these effects for realistic interactions between an electron beam and a laser pulse, and their influence on high-precision Compton scattering light sources.
Date: February 23, 2010
Creator: Hartemann, F V; Albert, F; Siders, C W & Barty, C P
Partner: UNT Libraries Government Documents Department

Design and construction of a radiation resistant quadrupole using metal oxide insulated CICC

Description: The construction of a engineering test model of a radiation resistant quadrupole is described. The cold-iron quadrupole uses coils fabricated from metal-oixide (synthetic spinel) insulated Cable-In-Conduit-Conductor (CICC). The superconductor is NbTi in a copper matrix. The quadrupole is designed to produce a pole-tip field of 2 T with an operating current of 7,000 A.
Date: December 28, 2012
Creator: Zeller, Albert F.
Partner: UNT Libraries Government Documents Department

Preliminary Report on Geologic Investigations in White Canyon, San Juan County, Utah, 1952

Description: From introduction: Field work, begun in the field season of 1951, was continued by the U. S. Geological Survey in the White Canyon area, San Juan County, Utah, from May 1 to October 28, 1952, The objectives of this work were to study the habits and character of uranium deposits in the area, to determine control and guides to ore and suitable areas for physical exploration, and to map and study the ore-bearing and adjacent strata to determine the regional geologic controls and habits of the uranium deposits, The White Canyon project is part of a regional mapping program on the Colorado Plateau being conducted by the Geological Survey on behalf of the U. S. Atomic Energy Commission.
Date: January 1953
Creator: Trites, Albert F., Jr. & Finnell, Tommy L.
Partner: UNT Libraries Government Documents Department

Laser System for Livermore's Mono Energetic Gamma-Ray Source

Description: A Mono-energetic Gamma-ray (MEGa-ray) source, based on Compton scattering of a high-intensity laser beam off a highly relativistic electron beam, requires highly specialized laser systems. To minimize the bandwidth of the {gamma}-ray beam, the scattering laser must have minimal bandwidth, but also match the electron beam depth of focus in length. This requires a {approx}1 J, 10 ps, fourier-transform-limited laser system. Also required is a high-brightness electron beam, best provided by a photoinjector. This electron source requires a second laser system with stringent requirements on the beam including flat transverse and longitudinal profiles and fast rise times. Furthermore, these systems must be synchronized to each other with ps-scale accuracy. Using a novel hyper-dispersion compressor configuration and advanced fiber amplifiers and diode-pumped Nd:YAG amplifiers, we have designed laser systems that meet these challenges for the X-band photoinjector and Compton-scattering source being built at Lawrence Livermore National Laboratory.
Date: March 14, 2011
Creator: Gibson, D; Albert, F; Bayramian, A; Marsh, R; Messerly, M; Ebbers, C et al.
Partner: UNT Libraries Government Documents Department

Geology of the Happy Jack Mine, White Canyon Area, San Juan County, Utah

Description: From abstract: The Happy Jack mine is in the White Canyon area, San Juan County, Utah. Production is from high-grade uranium deposits in the Shinarump conglomerate of Triassic age. The Shinarump strata range from 161/2 to 40 feet in thickness and the lower part of these beds fills an eastward-trending channel that is more than 750 feet wide and 10 feet deep.
Date: 1955
Creator: Trites, Albert F., Jr. & Chew, Randall T., III
Partner: UNT Libraries Government Documents Department

The Uranium, Tin, and Copper Deposits at Majuba Hill, Pershing County, Nevada

Description: From abstract: Uranium is associated with copper and tin ores in the Majuba Hill area, Antelope mining district, in the central part of the Antelope Range, Pershing County, Nev. About 23, 000 tons of copper and 200 tons of tin ore, a small quantity of lead-silver ore, and some arsenic-silver ore have been produced from the Majuba Hill mine, the Last Chance mine, and a mine in sec. 34, T. 33 N., R. 31 E.
Date: December 1952
Creator: Thurston, Ralph H. & Trites, Albert F., Jr.
Partner: UNT Libraries Government Documents Department

Preliminary Report on the Geology of the Tiger (Hideout) Claim, White Canyon Area, San Juan County, Utah, with Recommendations for Exploration for Geologic Information

Description: From introduction: The purpose of the mapping was to study the habits of the uranium minerals with relation to the geologic features of the White Canyon area, The work has been done by the U. S. Geological Survey on behalf of the Atomic Energy Commission. The Tiger claim is recommended for exploration by diamond drilling to obtain geologic information on the trend, length, depth, and width of the scour channel, and the relationship of uranium and copper minerals to the Shinarump-filled channel and to fractures.
Date: October 1952
Creator: Finnell, Tommy L.; Renzetti, B. L. & Trites, Albert F., Jr.
Partner: UNT Libraries Government Documents Department

Ultracompact Accelerator Technology for a Next-Generation Gamma-Ray Source

Description: This presentation reported on the technology choices and progress manufacturing and testing the injector and accelerator of the 250 MeV ultra-compact Compton Scattering gamma-ray Source under development at LLNL for homeland security applications. This paper summarizes the status of various facets of current accelerator activities at LLNL. The major components for the X-band test station have been designed, fabricated, and await installation. The XL-4 klystron has been delivered, and will shortly be dressed and installed in the ScandiNova modulator. High power testing of the klystron into RF loads will follow, including adjustment of the modulator for the klystron load as necessary. Assembly of RF transport, test station supports, and accelerator components will follow. Commissioning will focus on processing the RF gun to full operating power, which corresponds to 200 MV/m peak electric field on the cathode surface. Single bunch benchmarking of the Mark 1 design will provide confidence that this first structure operates as designed, and will serve as a solid starting point for subsequent changes, such as a removable photocathode, and the use of various cathode materials for enhanced quantum efficiency. Charge scaling experiments will follow, partly to confirm predictions, as well as to identify important causes of emittance growth, and their scaling with charge. Multi-bunch operation will conclude testing of the Mark 1 RF gun, and allow verification of code predictions, direct measurement of bunch-to-bunch effects, and initial implementation compensation mechanisms. Modeling will continue and focus on supporting the commissioning and experimental program, as well as seeking to improve all facets of linac produced Compton gamma-rays.
Date: May 14, 2012
Creator: Marsh, R A; Albert, F; Anderson, S G; Gibson, D J; Wu, S S; Hartemann, F V et al.
Partner: UNT Libraries Government Documents Department

Techniques and use of a tunable, laser-based, MeV-Class Compton scattering light source

Description: A Compton scattering {gamma}-ray source, capable of producing photons with energies ranging from 0.1 MeV to 0.9 MeV has been commissioned and characterized, and then used to perform nuclear resonance fluorescence (NRF) experiments. The key source parameters are the size (0.01 mm{sup 2}), horizontal and vertical divergence (6 x 10 mrad{sup 2}), duration (10 ps), spectrum and intensity (10{sup 5} photons/shot). These parameters are summarized by the peak brightness, 1.5 x 10{sup 15} photons/mm{sup 2}/mrad{sup 2}/s/0.1%bandwidth, measured at 478 keV. Additional measurements of the flux as a function of the timing difference between the drive laser pulse and the relativistic photoelectron bunch, {gamma}-ray beam profile, and background evaluations are presented. These results are systematically compared to theoretical models and computer simulations. NRF measurements performed on {sup 7}Li in LiH demonstrate the potential of Compton scattering photon sources to accurately detect isotopes in situ.
Date: June 30, 2009
Creator: Albert, F; Anderson, S G; Gibson, D J; Hagmann, C A; Johnson, M S; Messerly, M et al.
Partner: UNT Libraries Government Documents Department

Design and Operation of a tunable MeV-level Compton-scattering-based (gamma-ray) source

Description: A mono-energetic gamma-ray (MEGa-ray) source based on Compton-scattering, targeting nuclear physics applications such as nuclear resonance fluorescence, has been constructed and commissioned at Lawrence Livermore National Laboratory. In this paper, the overall architecture of the system, as well as some of the critical design decisions made in the development of the source, are discussed. The performances of the two laser systems (one for electron production, one for scattering), the electron photoinjector, and the linear accelerator are also detailed, and initial {gamma}-ray results are presented.
Date: July 7, 2009
Creator: Gibson, D J; Albert, F; Anderson, S G; Betts, S M; Messerly, M J; Phan, H H et al.
Partner: UNT Libraries Government Documents Department

Advanced Compton scattering light source R&D at LLNL

Description: We report the design and current status of a monoenergetic laser-based Compton scattering 0.5-2.5 MeV {gamma}-ray source. Previous nuclear resonance fluorescence results and future linac and laser developments for the source are presented. At MeV photon energies relevant for nuclear processes, Compton scattering light sources are attractive because of their relative compactness and improved brightness above 100 keV, compared to typical 4th generation synchrotrons. Recent progress in accelerator physics and laser technology have enabled the development of a new class of tunable Mono-Energetic Gamma-Ray (MEGa-Ray) light sources based on Compton scattering between a high-brightness, relativistic electron beam and a high intensity laser pulse produced via chirped-pulse amplification (CPA). A new precision, tunable gamma-ray source driven by a compact, high-gradient X-band linac is currently under development and construction at LLNL. High-brightness, relativistic electron bunches produced by an X-band linac designed in collaboration with SLAC will interact with a Joule-class, 10 ps, diode-pumped CPA laser pulse to generate tunable {gamma}-rays in the 0.5-2.5 MeV photon energy range via Compton scattering. Based on the success of the previous Thomson-Radiated Extreme X-rays (T-REX) Compton scattering source at LLNL, the source will be used to excite nuclear resonance fluorescence lines in various isotopes; applications include homeland security, stockpile science and surveillance, nuclear fuel assay, and waste imaging and assay. After a brief presentation of successful nuclear resonance fluorescence (NRF) experiments done with T-REX, the new source design, key parameters, and current status are presented.
Date: February 16, 2010
Creator: Albert, F; Anderson, S G; Anderson, G; Betts, S M; Chu, T S; Gibson, D J et al.
Partner: UNT Libraries Government Documents Department

LASER WAKEFIELD ACCELERATION BEYOND 1 GeV USING IONIZATION INDUCED INJECTION*

Description: A series of laser wake field accelerator experiments leading to electron energy exceeding 1 GeV are described. Theoretical concepts and experimental methods developed while conducting experiments using the 10 TW Ti:Sapphire laser at UCLA were implemented and transferred successfully to the 100 TW Callisto Laser System at the Jupiter Laser Facility at LLNL. To reach electron energies greater than 1 GeV with current laser systems, it is necessary to inject and trap electrons into the wake and to guide the laser for more than 1 cm of plasma. Using the 10 TW laser, the physics of self-guiding and the limitations in regards to pump depletion over cm-scale plasmas were demonstrated. Furthermore, a novel injection mechanism was explored which allows injection by ionization at conditions necessary for generating electron energies greater than a GeV. The 10 TW results were followed by self-guiding at the 100 TW scale over cm plasma lengths. The energy of the self-injected electrons, at 3 x 10{sup 18} cm{sup -3} plasma density, was limited by dephasing to 720 MeV. Implementation of ionization injection allowed extending the acceleration well beyond a centimeter and 1.4 GeV electrons were measured.
Date: March 22, 2011
Creator: Marsh, K A; Clayton, C E; Joshi, C; Lu, W; Mori, W B; Pak, A et al.
Partner: UNT Libraries Government Documents Department