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Pion correlations as a function of atomic mass in heavy ion collisions

Description: The method of two pion interferometry was used to obtain source-size and lifetime parameters for the pions produced in heavy ion collisions. The systems used were 1.70 {center dot} A GeV {sup 56}Fe + Fe, 1.82 {center dot} A GeV {sup 40}Ar + KCl and 1.54 {center dot} A GeV {sup 93}Nb + Nb, allowing for a search for dependences on the atomic number. Two acceptances (centered, in the lab., at {approximately} 0{degrees} and 45{degrees}) were used for each system, allowing a search for dependences on the viewing angle. The correlation functions were calculated by comparing the data samples to background (or reference) samples made using the method of event mixing, where pions from different events are combined to produce a data sample in which the Bose-Einstein correlation effect is absent. The effect of the correlation function on the background samples is calculated, and a method for weighting the events to remove the residual correlation effect is presented. The effect of the spectrometer design on the measured correlation functions is discussed, as are methods for correcting for these effects during the data analysis. 58 refs., 39 figs., 18 tabs.
Date: November 26, 1989
Creator: Chacon, A.D.
Partner: UNT Libraries Government Documents Department
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SOLUBLE NEUTRON POISONS AS A PRIMARY CRITICALITY CONTROL IN SHIELDED AND CONTAINED RADIOCHEMICAL FACILITIES

Description: Studies indicated that the use of soluble poisons as a primary criticality control offers economic and other advantages in that it permits the factors of vessel size and shape and solution concentrations to be dictated by considerations other than those of criticality. It is believed that soluble poison criticality control can be made as reliable as other methods of coaditional control if the application is preceded by adequate development work and is monitored by multiple. independent safeguards. The studies included multigroup machine calculations of the required content of poisons in solutions of fissile and fertile material, a compilation of data on the detection, stability, decontamination, and costs of soluble poisons, and an assessment of the possible effects of a nuclear excursion. (auth)
Date: July 26, 1962
Creator: Nichols, J.P.
Partner: UNT Libraries Government Documents Department
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Chemical Technology Division, Unit Operations Section Monthly Progress Report, May 1961

Description: The experimental results on the oxidation of H from a He stream with CuO pellets were very close to the predicted behavior based on the mathematical model. Experimental measurements of uranyl sulfate loading rates on chloride equilibrated resin showed little variation with solution concentrations. A tentative flowsbeet was proposed for cost analysis of processing a Pebble Bed Reactor. A U-Zr plate was dissolved in nitrate-free Zirflex solution. An authentic TRIGA prototype was processed in engineering-scale equipment. Three 4- stage leacher model dissolution runs were made, two of which used 8 M HNO/sub 3/ and one used 4 M HNO/sub 3/. Flooding rates and holdup data were obtained for sieve plate pulse columns under 5% TBP - l.8 Mi Al(NO/sub 3/)/sub 3/ flowsheet conditions. A Purex waste calcination run (R-37) was made using sodium anid imagnesium to reduce sulfate volatility. (auth)
Date: December 26, 1961
Creator: Whatley, M. E.; Haas, P. A.; Horton, R. W.; Ryon, A. D.; Suddath, J. C. & Watson, C. D.
Partner: UNT Libraries Government Documents Department
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The New Left: Students for a Democratic Society, A Supplement

Description: This report discusses Students for a Democratic Society (SDS) and their Marxist views and activities aimed at uniting students and workers. Splinter factions of SDS which staged violent protests in Chicago in the summer of 1969 are discussed in detail along with a prognosis on their likely levels of success in recruiting more students to their cause.
Date: November 26, 1969
Creator: Jones, Richard S.
Partner: UNT Libraries Government Documents Department
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[News Script: 703rd]

Description: Script from the WBAP-TV/NBC station in Fort Worth, Texas relating a news story.
Date: October 26, 1968
Creator: WBAP-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections
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[RE: Strategic Planning Vision Statements Meeting, May 26, 1993]

Description: Photocopy of a letter from Vicki Rosenberg, program officer of the Getty Center, to the Regional and Californian Institute Directors, in regards to a Matching Fund meeting. Rosenberg notes that in her previous memo the dates on the agenda were incorrect and she is sending a revised agenda enclosed with the letter. The matching fund meeting starts October 4th and ends October 8th.
Date: May 26, 1993
Creator: Rosenberg, Vicki
Partner: UNT Libraries Special Collections
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[Letter from Bill McCarter and Jack Davis to Don R. Roberts, March 26, 1991]

Description: Photocopy of a letter from Bill McCarter and Jack Davis, co-directors of North Texas Institute for Educators on the Visual Arts, to Don R. Roberts, Superintendent for Forth Worth ISD. In discussion of Roberts supportive efforts to implement discipline-art based education, DBAE in Fort Worth. NTIEVA invites Roberts to a reception and dinner on June 29th, to thank him and other retiring superintendents from their consortium districts.
Date: March 26, 1991
Creator: Davis, Donald Jack & McCarter, William
Partner: UNT Libraries Special Collections
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[Letter from Cassandra Broadus to Grace Berghauser, April 26, 1991]

Description: Photocopy of a letter from Cassandra Broadus, North Texas Institute for Educators on the Visual Arts, to Grace Berghauser, teacher at Pilot Point Elementary School. Commending Berghauser on her students and their excellent manners and behavior during Broadus's tour of the classroom. Broadus has enclosed an activity that she has written for the Art-O-Gram, an article published for the Fort Worth Star-Telegram, she believes Berghauser will find interesting for her classroom.
Date: April 26, 1991
Creator: Broadus, Cassandra
Partner: UNT Libraries Special Collections
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[Letter from Jack Davis and Bill McCarter, to Linus Wright, June 26, 1987]

Description: Photocopy of a letter from Jack Davis and Bill McCarter, co-directors of North Texas Institute for Educators on the Visual Arts, to Linus Wright, Superintendent of Dallas ISD. Davis and McCarter regret that Wright was unable to join them for the executive briefing on the North Texas Regional Institute for Educators on the Visual Arts, "North Texas Institute for Educators on the Visual Arts" (NTIEVA), Wednesday, June 19. Following the briefing was an all-day workshop, Friday, June 21 which was attended by staff representatives from each consortium in the Institute, to discuss grant proposals which with offer opportunities for staff development and curriculum implementation in the visual arts. Enclosed at the end of the letter to Wright is information the functional committees and their list of responsibilities, for the upcoming Matching Funds Advisory Committee and Wright's assistance in its regard. Enclosed information not present with letter.
Date: June 26, 1987
Creator: Davis, Donald Jack & McCarter, William
Partner: UNT Libraries Special Collections
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[Letter from John Grisby to Bill McCarter and Jack Davis, January 26, 1994]

Description: Photocopy of a letter from John Grisby, Superintendent for Pilot Point ISD, to Bill McCarter and Jack Davis, co-directors of North Texas Institute for Educators on the Visual Arts. In regards to Pilot Points' commitment as a full time partner in the North Texas Institute for Educators on the Visual Arts as well as their participation in a full two week summer institute. Grisby has attached to the letter stipend worksheets based on the salary of the faculty to be involved with the institute.
Date: January 26, 1994
Creator: Grisby, John
Partner: UNT Libraries Special Collections
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[Note from John Paul Batiste to Deborah, January 1, 1996]

Description: Photocopy of a note from John Paul Batiste, executive director for the Texas Commission on the Arts, to a woman named Deborah, in regards of her wanting a copy of a letter sent from Jack Davis to Paul. The letter from Davis is in regards to a proposal which the Statewide Working Group for Arts Education made to the Tremaine Foundation for funds to assist in assuring the Arts are included in the Goals 2000 education-reform planning process in Texas.
Date: January 26, 1996
Creator: Batiste, John Paul
Partner: UNT Libraries Special Collections
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[Document from Bill McCarter to Beverly Fletcher, March 26, 1991]

Description: Photocopy of a document from Bill McCarter, Co-Director of North Texas Institute for Educators on the Visual Arts, to Beverly Fletcher. The document is separated into two sections, the first section being about Dr. Jack Davis, Provost of UNT and a major figure in Art Education having won many awards for his service to the discipline of art education along with Dr. Bill McCarter, Regents Professor at UNT. Both Davis and McCarter are co-directors of NTIEVA, North Texas Institute for Educators on the Visual Arts, an institute funding by matching grants from the Getty Center, Amon Carter Foundation and others. The second part of the letter is about their program, DBAE, the approach to art education by involve art specialists and classroom teachers in expanding art to include not only art production but critical thinking, judgement and other formalities. The hand-written note at the bottom reads, "Bev. we need overhead projector - thanks."
Date: May 26, 1991
Creator: McCarter, William
Partner: UNT Libraries Special Collections
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Profile modification by the ponderomotive force in spherical targets

Description: Experiments have been performed by LLL which indicate a definite density profile steepening. One possible mechanism for this effect is the ponderomotive force. LASNEX has been modified to include the light momentum deposition in the form rho dv/dt = -nabla P - nabla(radical epsilon + radical 1/epsilon) I/2c. Results will be presented from numerical simulations on spherical glass targets at laser intensities from 10/sup 14/ to 10/sup 16/ watts/cm/sup 2/. Emphasis is placed on the nature of the density profile near the critical region as a function of laser intensity and plasma conditions. The existence of this sharp step, whose scale length is of the order of a micrometer may imply a local reduction in the thermal conductivity.
Date: October 26, 1977
Creator: Larsen, J. T. & Harte, J.
Partner: UNT Libraries Government Documents Department
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Development of superconductors for applications in high-field, high-current-density magnets for fusion research

Description: The development of large-bore, high-field magnets for fusion energy applications requires a system approach to both magnet and conductor design. At Lawrence Livermore National Laboratory (LLNL), the criteria used to choose superconductors include: strain tolerance, radiation tolerance, heat removal, stability, fabricability, and cost. We report on the performance of industrially produced, prototype, Ti-modified Nb/sub 3/Sn wires developed with LLNL support. Wire performance characteristics evaluated include critical current as a function of magnetic field, temperature, and applied strain. Tests were performed to determine how this performance translates to the performance of a cable-in-conduit conductor system using this wire. An alternative to Nb/sub 3/Sn superconductors is NbN, which is strain and radiation insensitive. We report preliminary efforts to produce multifilamentary NbN conductors by liquid-metal infiltration of NbN-coated, high-strength fibers. In addition, we discuss the fabrication of multifilamentary NbN conductors and their possible impact on magnet design.
Date: September 26, 1986
Creator: Summers, L. T. & Miller, J. R.
Partner: UNT Libraries Government Documents Department
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Exploding pusher targets for the SHIVA laser system

Description: The first targets for the 20 TW SHIVA laser system were designed. They are simple glass micro-balloons, approximately 300 ..mu..m in diameter and 2 ..mu..m thick, filled with D-T gas. Using LASNEX, whose model physics was utilized successfully for ARGUS targets, we optimize for both gain and yield. The target behaves as an exploding pusher. Different simple analytic models for the physics of this mode are presented, and are tested by comparing their scaling predictions, at constant absorbed power, with those demonstrated by LASNEX. Emphasis is placed on successful prediction of the basic quantities of peak ion temperature and compression, rather than neutron yield or n tau.
Date: September 26, 1977
Creator: Rosen, M. D.; Larsen, J. T. & Nuckolls, J. H.
Partner: UNT Libraries Government Documents Department
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NIGHTMARE-AN IBM 7090 CODE FOR THE CALCULATION OF GAMMA HEATING IN CYLINDRICAL GEOMETRY

Description: The NIGHTMARE program calculates the gamma-dose rate at any point in or near a reactor by means of the NDA buildup-factor method. The source distributton is obtained from a two-group, two-dimensional diffusion code (EQUIPOISE-2). Seven gamma-energy groups are used. As many as nine different concentric cylindrical regions may be considered, but only radial variation of attenuation and buildup properties is permdtted. Two schemes of estimating buildup factors through a succession of materials are built into the code, and results may be obtained by using either or both methods. An IBM 7090 computer wtth seven tape untts is required. Computations are performed at the approximate rate of l0,000/n mesh points per minute, where n is the number of axial, radial, and angular increments. The program is run under the control of the IBM 7090 MONITOR system. (auth)
Date: February 26, 1962
Creator: Tobias, M.L.; Vondy, D.R. & Lietzke, M.P.
Partner: UNT Libraries Government Documents Department
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Investigation of strain birefringence and wavefront distortion in 001 plates of KD sub 2 PO sub 4

Description: When 001 plates of KD{sub 2}PO{sub 4} (KD*P) are used in Pockels cells, strain induced refractive index variations result in beam depolarization and transmitted wavefront distortion. The depolarization is determined by the induced birefringence while the wavefront distortion is controlled by the average index shift. Here we show that the birefringence is determined by the shear stress in the xy-plane of the crystal while the average index shift depends only on the normal stresses. Furthermore, for depolarization losses of 0.1 to 1.0% and wavefront distortion of 0.1 to 1.0{lambda}, the critical range of stress is 10{sup 5} to 10{sup 6} Pa. We also present measured depolarization loss and wavefront distortion profiles for 5, 16 and 27cm, 95% deuterated, KD*P crystals. Using the analysis described above we show that the maximum internal stresses in the crystals are within the critical range, but that the area averaged stresses are substantially lower. We find that crystals from different locations along the length of a boule have similar strain birefringence and wavefront distortion profiles indicating that the growth conditions which generate the internal strain persist throughout much of the growth history of the boule. Finally, we discuss potential sources of strain in KD*P. 8 refs., 3 figs.
Date: August 26, 1991
Creator: De Yoreo, J. J. & Woods, B. W.
Partner: UNT Libraries Government Documents Department
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Conspray dynamic sleeve piston coal feeder. Phase II. Verification tests. Final technical report

Description: This report details the performance of Phase II: Verification Tests of the Conspray dynamic sleeve piston coal feeder. The machine performed for 200 hours at 700 psi backpressure, utilizing a 70% to 200 mesh Utah bituminous coal as feedstock. All test work was satisfactorily completed. A post-test inspection was performed. A report of component wear and failures incurred in testing is included as well as suggestions for machine upgrades. The overall conclusion is that the dynamic sleeve piston feeder has proven its ability to operate safely and reliably. When problems have occurred, the machine has demonstrated inherent safety by shutting down without endangering process or personnel. With the recommended improvements incorporated into the feeder, the unit will be ready for installation on a pilot scale coal gasifier. 9 figures, 11 tables.
Date: January 26, 1984
Partner: UNT Libraries Government Documents Department
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