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Lithospheric processes

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The main objective was to improve understanding of the origin and evolution of the Earth`s lithosphere by studying selected processes, such as deformation and magmatic intrusion during crustal extension, formation and extraction of mantle melts, fluid transport of heat and mass, and surface processes that respond to deep-seated events. Additional ob… more
Date: November 1, 1997
Creator: Baldridge, W. S.; Wohletz, K. & Fehler, M. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Exposure History of Separated Phases from the Kapoeta Meteorite

Description: The cosmogenic radionuclides, {sup 10}Be (1.5 Ma), {sup 26}Al (0.705 Ma), {sup 36}Cl (0.301 Ma), and {sup 53}Mn (3.7 Ma) were measured in selected clasts and matrix samples from the howardite Kapoeta. This work is an extension of that based on {sup 10}Be and {sup 26}Al [1]. Recent work based on measurements of cosmogenic {sup 21}Ne suggest the possibility of a complex recent exposure history for Kapoeta. The measurement of these radionuclides, in conjunction with production rates based on Monte… more
Date: January 14, 2000
Creator: Caffee, M W; Nishiizumi, K & Mazarik, J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of the beta-neutrino correlation in laser trapped {sup 21}Na

Description: Trapped radioactive atoms are an appealing source for precise measurements of the beta-neutrino correlation coefficient, a, since the momentum of the neutrino can be inferred from the detection of the unperturbed low-energy recoil daughter nucleus. Sodium-21 is produced on-line at the 88'' cyclotron at Lawrence Berkeley National Laboratory, and 8e5 atoms have been maintained in a magneto-optical trap. A static electric field draws daughter Neon-21 ions to a microchannel plate detector and betas… more
Date: June 1, 2003
Creator: Scielzo, Nicholas David
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Statistical methods for including two-body forces in large system calculations

Description: Large systems of interacting particles are often treated by assuming that the effect on any one particle of the remaining N-1 may be approximated by an average potential. This approach reduces the problem to that of finding the bound-state solutions for a particle in a potential; statistical mechanics is then used to obtain the properties of the many-body system. In some physical systems this approach may not be acceptable, because the two-body force component cannot be treated in this one-body… more
Date: July 1, 1980
Creator: Grimes, S.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mound Facility activities in chemical and physical research: July-December 1979

Description: Research is reported in the following fields: isotope separation (Ar, C, He, Kr, Ne, O, Xe), low-temperature research (H intermolecular potential functions, gas analysis in trennschaukel), separation chemistry (/sup 229/Th, /sup 231/Pa, /sup 230/Th, /sup 234/U), separation research (liquid thermal diffusion, Ca isotope separation, molecular beam scattering, mutual diffusion of noble gas mixtures, lithium chemical exchange with cryptands), and calculations in plutonium chemistry (algorithms, val… more
Date: June 18, 1980
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transfer and breakup reactions at intermediate energies

Description: The origin of the quasi-elastic peak in peripheral heavy-ion reactions is discussed in terms of inelastic scattering and transfer reactions to unbound states of the primary projectile-like fragment. The situation is analogous to the use of reverse kinematics in fusion reactions, a technique in which the object of study is moving with nearly the beam velocity. It appears that several important features of the quasi-elastic peak may be explained by this approach. Projectile-breakup reactions have… more
Date: April 1, 1986
Creator: Stokstad, R.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculation of spin cutoff parameters using moment techniques

Description: Spectral distribution methods are often applied to the calculation of nuclear level densities. If their distribution in spin is required in addition to the total number of levels at each energy, the spin-cutoff parameter and its energy dependence must be known. Recent calculations of the spin-cutoff parameters have shown qualitative agreement with data. Reasons for the remaining discrepancies are discussed, and proecdures for improving agreement between theory and experiment are suggested. 8 fi… more
Date: September 1, 1979
Creator: Grimes, S.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Representative-vector method for calculating operator-moments

Description: The utility of operator-moments or traces in the various applications of spectral-distribution theory is well documented. To take full advantage of the powerful entree that spectral distribution theory offers in nuclear physics, it may be generally necessary to have many moments beyond th first two hamiltonian moments <H> and <H/sup 2/>. In order to calculate, for one example, level densities reliably in the excitation-energy regions of physical interest, it may be necessary to have the moments… more
Date: September 1, 1979
Creator: Bloom, S.D. & Hausman, R.F. Jr.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Half life of /sup 26/Al

Description: The half-life of /sup 26/Al has been redetermined because of suggestions of an error in the accepted value based on its use in calculating /sup 21/Ne production rates from cosmic rays in meteorites. Two solutions of /sup 26/Al were analyzed for the specific radioactivity and mass spectrometric determination of the /sup 26/Al concentration. The half-life obtained for /sup 26/Al was 7.05 x 10/sup 5/ years +- 3.7% at the two sigma level. This is identical to the accepted value of 7.16 x 10/sup 5/ … more
Date: January 1, 1983
Creator: Norris, T. L.; Gancarz, A. J.; Rokop, D. J. & Thomas, K. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stable isotope sales: Mound Laboratory customer and shipment summaries, FY-1975

Description: A listing is given of Mound Laboratory's sales of stable isotopes of noble gases, carbon, oxygen, nitrogen, and sulfur for Fiscal Year 1975. Purchasers are listed alphabetically and are divided into domestic and foreign groups. A cross reference index by location is included for domestic customers. Cross reference listings by isotope purchased are included for all customers.
Date: April 30, 1976
Creator: Eck, C. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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