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Experiment to measure the gravitational force on the antiproton

Description: A collaboration has been formed to measure the acceleration of antiprotons in the earth's gravitational field. The technique is to produce, decelerate, and trap quantities of antiprotons, to cool them to untralow energy, and to measure their acceleration in a time-of-flight experiment. Present plans and the results of initial efforts toward this end are presented.
Date: January 1, 1985
Creator: Brown, R.E.
Partner: UNT Libraries Government Documents Department

Light nuclei: an experimental proving ground for the microscopic cluster model. [Review]

Description: A selected review is given of comparisons of experimental data for low-mass nuclear systems with results of calculations using microscopic cluster models. Stress is on the mass-4, -7, and -8 systems. Topics include influence of components of the nucleon-nucleon force, some consequences of the Pauli principle, effects of the Coulomb-exchange interaction, specific distortion, absorption in elastic scattering, and future needs and directions. Some as yet unpublished results are presented.
Date: January 1, 1978
Creator: Brown, R.E.
Partner: UNT Libraries Government Documents Department

[Receipt of Levi Perryman and W. A. Morris, September 24, 1879]

Description: Three receipts, one of W. A. Morris and two of Levi Perryman. W. A. Morris received %5.40 for clerk costs in case No. 512. Levi Perryman received through W. A. Morris $2.60 for clerk costs in case No. 521 and $4.80 for clerk costs in case No. 523. All receipts are signed by the District Clerk R. E. Brown.
Date: September 24, 1879
Creator: Brown, R. E.
Partner: UNT Libraries Special Collections

Hydrogen fusion-energy reactions

Description: At the Los Alamos Ion Beam Facility we have installed a low-energy fusion cross section (LEFCS) apparatus specifically designed to measure cross sections to high accuracy for the various fusion-energy reactions among the hydrogen isotopes in the bombarding-energy range 10 to 120 keV. To date, we have completed and published our study of the D(t,..cap alpha..)n reaction, have finished data-taking for the D(d,p)T and D(d,/sup 3/He)n reactions, and have nearly finished data-taking for the T(t,..cap alpha..)nn reaction. Here we describe the LEFCS facility, present final and preliminary results for these reactions, and compare them with R-matrix calculations. 16 refs., 10 figs.
Date: January 1, 1985
Creator: Brown, R.E. & Jarmie, N.
Partner: UNT Libraries Government Documents Department

Low-energy nuclear reactions with hydrogen isotopes

Description: Using the Los Alamos Low-Energy Fusion Cross-Section Facility (LEFCS), we have completed the study of the D(t,..cap alpha..)n reaction from E/sub t/ = 12.5 to 117 keV, and now have measured angular distributions of the reactions D(d,p)T and D(d,/sup 3/He)n from E/sub d/ = 20 to 117 keV. The experimental equipment features a windowless cryogenic target, a precision beam-intensity calorimeter, a 10- to 120-keV accelerator producing negative tritium ins, an accurate target gas-flow and temperature system, and a tritium gas-handling system. Most of the quite anisotropic angular distributions of the D + D reactions have relative errors of about 1% and the integrated cross sections have absolut errors of about 1.5%. Astrophysical S functions extracted from the data and also from a least-squares fit of a + b cos/sup 2/theta to the data show a curious behavior with energy. The cross sections, which agree with previous but less accurate data, are compared with R-Matrix calculations. We also show preliminary results for alpha-particle spectra of the T(t,..cap alpha..)nn reaction. A feature of this experiment is the flow through our windowless target of 1.5 standard liters of tritium gas per day.
Date: January 1, 1984
Creator: Jarmie, N. & Brown, R.E.
Partner: UNT Libraries Government Documents Department

Problems associated with the extension of the stratigraphic units of south-central Washington. Part II. The post basalt sediments

Description: There are four district stratigraphic units within the Pasco Basin which if interpreted on the basis of recent field evidence and described properly could be traced over most of southeastern Washington. At the present time these post-basalt sediments are described in the literature in such a way as to make extensive correlations impossible. Some descriptions overlap more than one unit whereas others describe only a part of the unit. It is proposed that all interested geologists in the Pacific Northwest now consider reconciling the differences which exist in the names and descriptions of those sedimentary deposits in light of this new evidence.
Date: March 26, 1965
Creator: Brown, D.J. & Brown, R.E.
Partner: UNT Libraries Government Documents Department

Nuclear reactions among the hydrogen isotopes at low energies

Description: The low-energy fusion cross-section (LEFCS) apparatus installed at the Los Alamos Van de Graaff facility has been used to measure the cross sections for the important fusion-energy reaction D(t,..cap alpha..)n over the triton bombarding energy range of 12.5 to 117 keV. This corresponds to an equivalent deuteron bombarding energy range of 8.3 to 78.1 keV and to a D + T plasma temperature (kT) range of 0.7 to 18.8 keV. Over most of the energy range the cross sections are accurate to 1.4%, with the error rising to 4.8% at the lowest energy. A data base was constructed for deuteron bombarding energies up to about 250 keV that included our data and four other data sets. This data base can be fitted quite well with a single-level (3/2/sup +/) resonance formula in the R-matrix formalism. Work is currently in progress on the D(d,p)T and D(d,/sup 3/He)n reactions, with studies of D(t,..gamma..) and T(t,..cap alpha..)nn planned for the future.
Date: January 1, 1982
Creator: Brown, R.E.; Jarmie, N. & Hardekopf, R.A.
Partner: UNT Libraries Government Documents Department

Heavy Aggregate Investigation

Description: This report follows a manuscript report made in January 11, 1952, and provides results of a survey that gives corrections as well as suggestions for new and local sources of aggregate material in comparison to the original report. These reports were made in response to a heavy desire of improvement in reactor design and shielding.
Date: December 19, 1952
Creator: Brown, R. E.
Partner: UNT Libraries Government Documents Department

Study of d + $sup 3$H and d + $sup 3$He systems with the resonating-group method

Description: The one-channel resonating-group method, together with a phenomenological imaginary potential, is used to study the d + /sup 3/H and d + / sup 4/He systems. The calculations show that, because of the Pauli exclusion principle, these systems possess the following rather interesting feature: in the s = 3/2 state they behave similar to the d + alpha system, whereas in the s = 1/ 2 state they behave more like the /sup 3/He + /sup 4/He system. Phase shifts are computed up to 1 = 7, and an R-matrix analysis of these phases indicates that there are a large number of levels with resonance energies below 12 MeV. Differential scattering and total-reaction cross sections are compared with experimental data at several cm energies from about 2 to 14 MeV. This comparison shows that the introduction of an odd-even orbital-angular-momentum dependence into the imaginary potential can improve the agreement of the calculation with experiment. ( auth)
Date: January 1, 1972
Creator: Chwieroth, F.S.; Brown, R.E.; Tang, C.C. & Thompson, D.R.
Partner: UNT Libraries Government Documents Department