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Feasibility of laser pumping with neutron fluxes from present-day large tokamaks

Description: The minimum fusion-neutron flux needed to observe nuclear-pumped lasing with tokamaks can be reduced substantially by optimizing neutron scattering into the laser cell, located between adjacent toroidal-field coils. The laser lines most readily pumped are probably the /sup 3/He-Ne lines at 0.633 ..mu.. and in the infrared, where the /sup 3/He-Ne gas is excited by energetic ions produced in the /sup 3/He(n,p)T reaction. These lines are expected to lase at the levels of D-T neutron flux foreseen … more
Date: August 1, 1986
Creator: Jassby, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Delayed neutron spectra from short pulse fission of uranium-235

Description: Delayed neutron spectra from individual short pulse (approx.50 ..mu..s) fission of small /sup 235/U samples (50 mg) were measured using a small (5 cm OD x 5 cm length) NE 213 neutron spectrometer. The irradiating fast neutron flux (approx.10/sup 13/ neutrons/cm/sup 2/) for these measurements was provided by the Godiva fast burst reactor at the Los Alamos Critical Experiment Facility (LACEF). A high speed pneumatic transfer system was used to transfer the 50 mg /sup 235/U samples from the irradi… more
Date: January 1, 1986
Creator: Atwater, H.F.; Goulding, C.A.; Moss, C.E.; Pederson, R.A.; Robba, A.A.; Wimett, T.F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation in the SLC final focus alcoves from beam losses in collimators and dumps. Revision

Description: There are various beam line components between the interaction point (IP) of the SLC and the beam dumps which will intercept enough beam to warrant calculating the radiation levels inside the final focus alcoves. The three types of devices which are of concern are the main dump, tune-up dumps, and adjustable collimators. Fluences of and doses from neutrons and photons in the alcoves are calculated. It is concluded that if the beam losses do occur as expected, many of the electronic components i… more
Date: October 1, 1986
Creator: Jenkins, T.M. & McCall, R.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fragmentation model applied to exclusive final states in photon-photon collisions

Description: Monte Carlo calculations with the Lund string fragmentation model are compared to experimental results on the reactions ..gamma gamma -->..2..pi../sup +/2..pi../sup -/, ..gamma gamma -->..K/sup +/K/sup -/..pi../sup +/..pi../sup -/ and ..gamma gamma -->..p anti p..pi../sup +/..pi../sup -/. It is found, that when the parameters of the Lund model are tuned to low energy, inclusive multi hadron production in photon-photon collisions, the cross sections of exclusive processes near threshold are qual… more
Date: July 1, 1986
Creator: Buijs, A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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/sup 3/He functions in tokamak-pumped laser systems

Description: /sup 3/He placed in an annular cell around a tokamak fusion generator can convert moderated fusion neutrons to energetic ions by the /sup 3/He(n,p)T reaction, and thereby excite gaseous lasants mixed with the /sup 3/He while simultaneously breeding tritium. The total /sup 3/He inventory is about 4 kg for large tokamak devices. Special configurations of toroidal-field magnets, neutron moderators and beryllium reflectors are required to permit nearly uniform neutron current into the laser cell wi… more
Date: October 1, 1986
Creator: Jassby, D. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accelerator Technology Program. Status report, April-September 1985

Description: This report presents highlights of major projects in the Accelerator Technology (AT) Division of the Los Alamos National Laboratory. Radio-frequency and microwave technology are dealt with. The p-bar gravity experiment, accelerator theory and simulation activities, the Proton Storage Ring, and the Fusion Materials Irradiation Test accelerator are discussed. Activities on the proposed LAMPF II accelerator, the BEAR (Beam Experiment Aboard Rocket) project, beam dynamics, the National Bureau of St… more
Date: September 1, 1986
Creator: Jameson, R.A. & Schriber, S.O. (comps.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hyperons in neutron stars

Description: Generalized beta equilibrium involving nucleons, hyperons, and isobars is examined for neutron star matter. The hyperons produce a considerable softening of the equation of state. It is shown that the observed masses of neutron stars can be used to settle a recent controversy concerning the nuclear compressibility. Compressibilities less than 200 MeV are incompatible with observed masses. 7 refs., 9 figs.
Date: April 1, 1986
Creator: Glendenning, N.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Multifragmentation in intermediate energy heavy ion collisions

Description: The GSL/LBL plastic ball/wall detector system was used to gain insight into the fragment production mechanism in Au + Au and Au + Fe reactions. Full azimuthal coverage for light particles (p,d,t,/sup 3/He,/sup 4/He) and intermediate mass fragments (z greater than 10) is achieved in the forward hemisphere in the center of mass system. The complete measurement of light particles allowed a global analysis of the events and a search for collective effects in fragment emission by comparing to flow e… more
Date: April 14, 1986
Creator: Jacak, B. V.; Britt, H. C.; Claesson, G.; Doss, K. G. R.; Ferguson, R.; Gavron, A. I. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fusion-neutron production in the TFTR with deuterium neutral beam injection

Description: We report measurements of the fusion reaction rate in the Tokamak Fusion Test Reactor (TFTR) covering a wide range of plasma conditions and injected neutral beam powers up to 6.3 MW. The fusion-neutron production rate in beam-injected plasmas decreases slightly with increasing plasma density n/sub e/, even though the energy confinement parameter n/sub e/tau/sub E/ generally increases with density. The measurements indicate and Fokker-Planck simulations show that with increasing density the sour… more
Date: June 1, 1986
Creator: Hendel, H. W.; England, A. C.; Jassby, D. L.; Mirin, A. A. & Nieschmidt, E. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High energy polarized beams from hyperon decays

Description: The use of various ways to utilize lambda decays to obtain polarized beams of protons and antiprotons is emphasized. Examples described are the Fermilab polarized beam, now under construction, and the use of similar techniques at other energies. Beam transport, spin precession and reversal systems, and polarimeters are also discussed. 8 refs., 4 figs.
Date: January 1, 1986
Creator: Underwood, D.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Soudan 2 nucleon decay experiment

Description: The Soudan 2 nucleon decay experiment consists of a 1.1 Kton fine grained iron tracking calorimeter. It has a very isotropic detection structure which along with its flexible trigger will allow detection of multiparticle and neutrino proton decay modes. The detector has now entered its construction stage.
Date: January 1, 1986
Creator: Thron, J. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tangential neutral-beam-driven instabilities in the Princeton beta experiment

Description: During tangential neutral beam injection into the PBX tokamak, bursts of two types of instabilities are observed. One instability occurs in the frequency range 120-210 kHz and the other oscillates predominately near the frequency of bulk plasma rotation (20-30 kHz). Both instabilities correlate with drops in neutron emission and burst in charge-exchange neutral flux, indicating that beam ions are removed from the center of the plasma by the instabilities. The central losses are comparable to th… more
Date: July 1, 1986
Creator: Heidbrink, W. W.; Bol, K.; Buchenauer, D.; Fonck, R.; Gammel, G.; Ida, K. et al.
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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Antimatter clusters from hadronizing quark-gluon plasma

Description: A realistic model is used for the phase transition between the color deconfining quark-gluon plasma phase and the color confining hadronic gas phase of nuclear matter to discuss the question how quarks and antiquarks hadronize in an expanding quark-gluon plasma. Particular attention is given to the problem associated with the latent heat and latent entropy set free in the hadronization process. Assuming a specific space-time scenario for the phase transition, relative abundances are computed fo… more
Date: January 1, 1986
Creator: Heinz, U.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In vivo monitoring of toxic metals: assessment of neutron activation and x-ray fluorescence techniques

Description: To date, cadmium, lead, aluminum, and mercury have been measured in vivo in humans. The possibilities of monitoring other toxic metals have also been demonstrated, but no human studies have been performed. Neutron activation analysis appears to be most suitable for Cd and Al measurements, while x-ray fluorescence is ideally suited for measurement of lead in superficial bone. Filtered neutron beams and polarized x-ray sources are being developed which will improve in vivo detection limits. Even … more
Date: January 1, 1986
Creator: Ellis, K.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Delta, iota and other meson spectroscopies

Description: This talk is given from the point of view of an experimentalist. Meson spectroscopy in the 1 to 3 GeV region is interesting because experiments exploring this region, in particular radiative psi decay, have found a rich structure of resonances too complicated to unravel with any one experiment, and not easily interpreted with any one theoretical model. None of the theoretical calculations predicting all kinds of interesting and exotic objects in this region is very convincing or reliable. Addit… more
Date: May 1, 1986
Creator: Lipkin, Harry J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin observables in proton-neutron scattering at intermediate energy

Description: A summary of np elastic scattering spin measurements at intermediate energy is given. Preliminary results from a LAMPF experiment to measure free neutron-proton elastic scattering spin-spin correlation parameters are presented. A longitudinally polarized proton target was used. These measurements are part of a program to determine the neutron-proton amplitudes in a model independent fashion at 500, 650, and 800 MeV. Some new proton-proton total cross sections in pure helicity states (..delta..s… more
Date: May 1, 1986
Creator: Spinka, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation effects in space

Description: The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)
Date: January 1, 1986
Creator: Fry, R.J.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of the Soudan 2 nucleon decay experiment

Description: Soudan 2 is an 1100-ton fine-grained tracking calorimeter now being constructed to search for nucleon decay. It is distinguished by superior background rejection for a wide variety of decay modes and by a trigger threshold low enough for 100 MeV neutrino-induced muons. A new laboratory large enough for an eventual 3300 ton experiment has been constructed in Minnesota's Soudan mine at a depth equivalent to 2200 meters of water. The detector will be assembled from 256 5-ton calorimeter modules, u… more
Date: June 1, 1986
Creator: May, E.N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electromagnetic Structure of Nuclei

Description: A brief review is given of selected topics in the electromagnetic structure of nucleons and nuclei, including nucleon form factors from both quantum chromodynamics and electron scattering data, measurements of the deuteron and triton form factors, quasi-elastic scattering, and the EMC effect. 47 refs., 13 figs. (LEW)
Date: July 1, 1986
Creator: Arnold, R. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atlas of photoneutron cross sections obtained with monoenergetic photons. Final edition, 1986

Description: In view of the need for a comprehensive compilation of photoneutron cross-section data, these monoenergetic-photon data are gathered together here and presented in a uniform format. This compilation updates and supersedes the earlier editions of this Atlas. A more complete compilation is being assembled by the photonuclear group at the National Bureau of Standards. 15 refs., 174 figs.
Date: June 1, 1986
Creator: Dietrich, S.S. & Berman, B.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Post-failure material movement in the PFR/TREAT experiments

Description: In the PFR/TREAT experiments the fast neutron hodoscope has provided experimental data on post-failure material movement during Transient Overpower and Transient Under-Cooled Overpower events. Analyses of selected experiments have been done, using SIMMER-II and SAS4A, to validate these codes. Full results of these analyses are presented in the paper. The general conclusion that can be drawn from the analyses that have been made so far is that the hodoscope is providing data which has appropriat… more
Date: January 1, 1986
Creator: Bauer, T. H.; Morman, J. A.; Hill, D. J.; DeVolpi, A. & Goldman, A. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Use of the (t,p) reaction for in-beam spectroscopy studies

Description: Triton induced reactions, such as the (t,p) reaction, can be used for in-beam gamma-ray and conversion-electron studies of nuclei that are somewhat neutron rich. We have developed systems for both conversion-electron and gamma-ray spectroscopy in coincidence with the outgoing energetic proton to identify the (t,p) reaction channel. Data from the /sup 142/Nd(t,p..gamma..) reaction illustrate several of the characteristics of this reaction for studying nuclear structure. Preliminary results from … more
Date: May 29, 1986
Creator: Henry, E.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flavor production in e sup + e sup - annihilation and in proton- proton interactions

Description: We compare the p{sub T} dependence of pion, kaon and proton production cross sections in the central rapidity region of e{sup {plus}}e{sup {minus}} annihilation events and in proton-proton collisions at ISR energies. We find similarities both in the p{sub T} dependence of cross sections and in the particle composition as a function of p{sub T}, in agreement with the hypothesis of a universal mechanism of particle production. 13 refs., 4 figs.
Date: January 1, 1986
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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