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Noise Considerations in Nuclear Pulse Amplifiers

Description: The effects of certain pulse-shaping networks on the signal-to-noise ratio of a nuclear pulse amplifier were considered. The shaping networks discussed are: equal RC-integrating and RC-differentiating time constant, single- delay-line clipper and RC integrator, and doubledelay-line clipper and RC integrator. The effects of these networks on the signal, when high count rates and overload pulses are present, were also considered. Equations and curves were developed for the energy resolution (sign… more
Date: December 20, 1961
Creator: Landis, D. A.
open access

Diffusion of Slow Electrons in Gases

Description: The properties of electrons in a gas and an external electric field, e.g., agitation velocity, free path, energy lost per collision, and collision cross sections, were determined for electrons of energy less than 2 ev in a large number of gases. The computations were made from previously measured values for Townsend's energy factor or the ratio of electron agitation energy to molecule thermal energy. Results are presented for hydrogen, nitrogen, carbon dioxide, methane, ethylene, cyclopropane, … more
Date: October 24, 1961
Creator: Forester, D. W. & Cochran, L. W.
open access

Ejection of Large Fragments in High-Energy Nuclear Reactions

Description: Several features of the production of Na/sup 24/ and Mg/sup 28/ fragments produced in the interaction of protons and He ions with Cu, Ag, Au, and U were investigated. Formation cross sections were determined for He ions of different energies between 320 and 880 Mev and for protons of 700 Mev. Thick- target recoil experiments were performed at bombarding energies of 0.7 and 3 Bev for protons, and 880 Mev for He ions. Also given are some recoil measurements of Na/sup 24/ from Al. Analysis of data… more
Date: September 1, 1961
Creator: Crespo, V. P.
open access

THE CARRIER-RECOMBINATION BEHAVIOR AND ANNEALING PROPERTIES OF RADIATION- INDUCED RECOMBINATION CENTERS IN GERMANIUM

Description: Carrier recombination and annealing of radioinduced recombination centers were investigated for both n- and ptype Ge. The experimental results are explained by a model in which recombination occurs at 0.36 ev above the valence band in gamma -irradiated, n-type Ge; the position of this level is shifted slightly downward for neutron-irradiated Ge. Trapping levels occur in As-doped Ge (at 0.17 ev above the valence band) which are not present in Sb-doped Ge. For p-type Ge, an energy level present i… more
Date: June 1, 1961
Creator: Curtis, O.L. Jr. & Crawford, J.H. Jr.
open access

Dynamic Simulation of Multi-Pass Pressurized Water Nuclear Power Plants by Analog Computer Techniques

Description: A kinetic model of the primary loop of a multi-pass pressurized water reactor power plant is developed to evaluate, by analog computer techniques, the transient response characteristics under conditions of steam generator load and reactor control rod perturbations. Using the 2-pass 28 Mw(t) SM-2 reactor as a typical plant, transient behavior patterns are illustrated and examined for a variety of load inputs, variations in plant constants, and analog model simplifications. (auth)
Date: June 1, 1961
Creator: Brondel, J. O.
open access

A Theoretical Study of the Transient Operation and Stability of Two-Phase Natural Circulation Loops

Description: Mathematical models of the time-dependent behavior of two-phase natural- circulation loops were used to predict the operation and to explain the unusual instability sometimes observed. The initial results obtained for a loop similar to the Univ. of Minnesota loop were used to formulate a more complex and accurate model, and the predicted transient behavior was in close agreement with the experimental results from the Minnesota loop. For a 300psia, high-pressure loop, unstable oscillatory behavi… more
Date: June 1, 1961
Creator: Garlid, K.; Amundson, N. R. & Isbin, H. S.
open access

Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

Description: ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar a… more
Date: June 1, 1961
Creator: Hornbaker, David Ross
open access

The Cosine-Cubed Neutron Spectrometer

Description: In an attempt to increase the efficiency, a proton recoil neutron spectrometer was built in which the proton detection crystal is in the shape of the surface formed by the rotation of the cos/sup 3/ THETA curve about the THETA = 0 axis where THETA is the angle between the direction of travel of the incident neutron and the direction of travel of the recoil proton. Such a construction makes the detector crystal conform to the range envelope of the protons recoiling from a neutron beam of suffici… more
Date: May 1, 1961
Creator: Thorngate, J. H.; Hurst, G. S.; Davis, F. J. & Reinhardt, P. W.
open access

Proton Capture Gamma Rays From Si$Sup 28$ in the Region of the Photonuclear Giant Resonance

Description: The Livermore 90 deg inch variable-energy cyclotron was used to measure the 90 deg excitation function for the Al/sup 27/(p, gamma )Si/sup 28/ reaction. Proton energies between 5 and 13 Mev were used which gave excitation energies in Si/sup 28/ corresponding to the region of the photonuclear giant resonance. Two gamma rays were observed: gamma /sub O/, the groundstate gamma ray and gamma / sub 1/ resulting from deexcitation through the first excited state of Si/sup 28/ at 1.78 Mev. They were de… more
Date: May 1, 1961
Creator: Gardner, C. C.
open access

Heavy-Ion Elastic Scattering

Description: The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with e… more
Date: April 17, 1961
Creator: Alster, Jonas
open access

The Magnetic Properties of Deformed Nuclei

Description: It is shown that the magnetic moments of odd-A deformed nuclei can be interpreted in terms of the independentparticle model with interconfigurational mixing due to the very-short-range residual forces. The latter are implied by using the empirically reduced spin gyromagnetic ratios. The effects of these residual forces on the collective gyromagnetic ratios g/sub R/ are discussed in terms of pair correlation. The effect of particle-rotation interaction on the magnetic moment and the collective g… more
Date: April 1, 1961
Creator: Chiao, L.
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