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Nature of atmospheric dust. Progress report to January 15, 1955

Description: Optical microscopic examination of air- and rain-borne dust shows most of the particles to be less than one micron in diameter. Electron microscopic examination of the same dust shows predominantly clusters of particles whose individual diameters are in the range 200 to 1000 A. The residue obtained by filtering rain water through a millipore filter is found to be slightly radioactive in more than half the cases observed.
Date: January 20, 1955
Creator: Heininger, C. & Turkevich, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THREE NEW DELAYED ALPHA EMITTERS OF LOW MASS

Description: Two new positron active isotopes, B{sup 8} and Na{sup 20}, have been found to decay to excited states of Be{sup 8} and Ne{sup 20}, which in turn decay 'instantaneously' by alpha emission. Their half-lives are 0.65 {+-} 0.1 sec. and 1/4 sec. respectively. N{sup 12} is also found to have a low energy positron group which leads to an {alpha}-unstable excited state in C{sup 12}. The masses of B{sup 8} and Na{sup 20} are 8.027 and 20.015 respectively. B{sup 8} decays by a 13.7 {+-} 0.3 Mev positron,… more
Date: May 31, 1950
Creator: Alvarez, Luis W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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STOPPING POWER AND ENERGY FOR ION PAIR PRODUCTION FOR 340 MEVPROTONS

Description: The relative stopping powers for 300 Mev protons of H, Li, Be, C, Al, Fe, Cu, Ag, Sn, W, Pb, and U have been measured. The results are shown in Table I. The energy spent per ion-pair production in the gases H{sub 2}, He, N{sub 2}, O{sub 2}, and A at 340 Mev proton energy has also been measured. The results are shown in Table II.
Date: August 3, 1950
Creator: Bakker, C.J. & Segre, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Proton-Proton Scattering at 340 MeV

Description: Measurements of the proton-proton differential scattering cross section using 340 Mev protons show a cross section approximately constant between 41{sup o} and 90{sup o} in the center of mass system. Two methods of counting the scattered protons have been used. The first method uses a counter telescope to count the scattered protons. The second method utilizes coincidences between counters which record the two protons involved in a single scattering process. The first method gives slightly high… more
Date: January 1, 1950
Creator: Chamberlain, Owen & Wiegand, Clyde
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The New Element Californium (Atomic Number 98)

Description: Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with about 35-Mev helium ions in the Berkeley Crocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and is thought to have the mass number 244. The observed mode of decay of 98{sup 244} is through the emission of alpha-particles, with energy of about 7.1 Mev, which agrees with predictions. Other consid… more
Date: June 19, 1950
Creator: Thompson, S. G.; Street Jr., K.; Ghiorso, A. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Californium Isotopes From Bombardment of Uranium With Carbonions

Description: The recent production and identification of isotopes of elements with atomic numbers up to six higher than the target element through bombardment with hexapositive 120-Mev carbon ions made it seem worthwhile to apply this technique to the transuranium region. Accordingly, small pieces of natural uranium metal (about 0.5 mil thick and 205 cm by 0.6 cm area) were irradiated in the internal carbon ion beam in the Berkeley 60-inch cyclotron. Following the irradiations, the uranium was dissolved in … more
Date: September 6, 1950
Creator: Ghiorso, A.; Thompson, S. G.; Street, Jr., K. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A MEASUREMENT OF THE POSITIVE pi- Mu DECAY LIFETIME

Description: The lifetime for the decay of a {pi} meson into {mu} meson and neutral particle was first measured by Richardson and later by Martinelli and Panofsky. The method was the same in both cases: The fraction of {pi} mesons surviving various times of flight is measured by placing photographic detectors at various path lengths from the target. In the experiment reported here we observe the time lag between the two bursts of fluorescence due to mesons decaying in a scintillation crystal. The first burs… more
Date: May 10, 1950
Creator: Chamberlain, O.; Mozely, R.F.; Steinberger, J. & Wiegand, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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'Fission' of Medium Weight Elements

Description: The fission reaction has been observed with high energy accelerator projectiles for elements as light as tantalum but has not been reported for medium weight elements. The present note presents evidence for the occurrence of reactions which are probably most properly described by the term 'fission' and which seem to occur with very small yield throughout the region where this type of reaction is only slightly exoergic or even endoergic with respect to mass balance. In the course of detailed inv… more
Date: May 29, 1950
Creator: Batzel, Roger T. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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ELEMENT 98

Description: Definite identification has been made of an isotope of the element with atomic number 98 through the irradiation of Cm{sup 242} with 35 Mev helium ions in the Berkeley Orocker Laboratory 60-inch cyclotron. The isotope which has been identified has an observed half-life of about 45 minutes and probably has the mass number 244. The observed mode of decay of the 98{sup 244} is through the emission of alpha-particles, with energy about 7.1 Mev, which agrees with predictions, and other consideration… more
Date: February 27, 1950
Creator: Thompson, S. G.; Street Jr., K.; Ghiorso, A. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The New Element Berkelium (Atomic Number 97)

Description: An isotope of the element with atomic number 97 has been discovered as a product of the helium-ion bombardment of americium. This isotope decays with the emission of alpha-particles of maximum energy 6.72 Mev (30 percent) and it emits lower energy alpha-particles of energies 6.55 Mev (53 percent) and 6.20 Mev (17 percent). The half-life of this isotope is 4.6 hours and it decays primarily by electron capture with about 0.1 percent branching decay by alpha-particle emission. The mass number is p… more
Date: April 26, 1950
Creator: Thompson, S. G.; Ghiorso, A. & Seaborg, G. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PHYSICS DIV. QUARTERLY REPORT, MAY, JUNE, JULY, 1950

Description: The X-ray Spectrum Produced by 322 Mev Electrons Striking a Platinum Target. The differential energy spectrum of the photons produced by 322 Mev electrons striking a 20 mil platinum target was measured by observing the energy of 3467 pairs produced in a one mil thick lead foil in a Wilson cloud chamber in a magnetic field of 10,000 gauss. The spectrum is found to agree with that predicted by the Bethe-Heitler bremsstrahlung theory using a Thomas-Fermi model with suitable corrections for the thi… more
Date: September 6, 1950
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of lithium in target slugs by neutron transmission

Description: An instrument was developed to measure nondestructively the lithium content of target slugs for the SRP reactors. The slugs consist of cylindrical pieces of Li-Al alloy, approximately 0.8 inches in diameter and 12 inches in length, clad with aluminum. The instrument utilizes neutron transmission to determine the Li content in the range 3% to 7% Li.
Date: February 1, 1955
Creator: Dexter, A.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Application of the Concepts of Particle Packing to the Consolication of Silicon Carbide Powders

Description: From introduction: Silicon carbide is being considered as a basis material for nonmetallic fuel elements because of its high thermal conductivity, low nuclear cross section, high resistance to thermal rupture, and high degree of stability at high temperature in air. A requirement of the fuel elements is that they be thin and have as low porosity as possible. One shape of element under consideration is 0.050 to 0.070 inch thick by a few inches in width and breadth.
Date: August 15, 1952
Creator: Harman, Cameron G.; Shinn, J., Jr. & Wagner, H. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fallout studies and assessment of radiological phenomena. Preliminary report. Project 32. 4 (of) Operation Plumbbob

Description: Data were obtained to evaluate the attenuation of photons, emitted from a fallout field, due to the surface roughness of the terrain. A study was made to determine the effect of the shot tower on the fallout material. Particles for comparison were collected from two detonations of equal scaled height, one tower supported and the other balloon supported. Data on time-dependent phenomena were recorded, as were physical characteristics of the fallout material. The use of small balloons as instrume… more
Date: November 1, 1957
Creator: Egeberg, L.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radioactive contamination in the environs of the Hanford Works for the period October, November, December 1949

Description: This report summarizes the measurements made for radioactive contamination in the environs of the Hanford Works. The principal sources of the radioactivity originating as a result of operations at Hanford which affect the environment in this area are the two waste stacks in the separations area and the cooling water from the four pile areas. Measurements are also made on samples taken from the Hanford waste systems which are primarily confined within the project proper. Although monthly summari… more
Date: March 2, 1950
Creator: Paas, H.J. & Singlevich, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Relative Yields of Nitrogen-17 Produced by 190-Mev Deuteron Bombardment

Description: "Yields of N¹⁷ relative to that produced in LiF have been measured in the 190-Mev deflected deuteron and the 380-Mev alpha beams of the 184-inch synchrocyclotron. The measurements have been performed in all the light elements from 0 through V, with the exception of Sc and the noble gases. In addition, yields were measured in the separated isotopes of Mg...Comparisons are made with other types of yield studies performed with neutrons and protons, and the areas of agreement are noted."
Date: April 13, 1955
Creator: Chupp, Warren William
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Nonadiabatic Effects in Single-Particle Orbits

Description: From introduction: "The containment of a charged particle in a mirror field has been studied analytically and numerically. Formulas are presented which give the change in the magnetic moment as it passes from one end of the machine to the other."
Date: March 1957
Creator: Garren, Alper; Henrich, L.; Northrop, Theodore G.; Riddell, R. & Smith, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutron Production by High-Energy Particles

Description: Abstract: "From neutron-yield measurements made with a MnSO4 detecting solution, the average number of neutrons produced per inelastic event is determined for a series of elements from lithium to uranium for 340-Mev protons, 190-and 315-Mev deuterons, 490-Mev He3 ions, and 90- and 160-Mev neutrons. The results are analyzed in an attempt to understand the total yield measurements for thick targets and to explain the variation of yield with the atomic number of the target."
Date: September 29, 1954
Creator: Crandall, Walter E. & Millburn, George P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Proposed Particle Containment Device

Description: Abstract: A device is proposed for confining charged particles to a localized region of space by means of the alternating electric field of a resonant cavity. The motion of single electrons in the field is stable. The limitations to particle density and temperature are discussed, and found to be too severe to allow the device to serve as a reactor, although it might be a useful laboratory tool.
Date: July 8, 1953
Creator: Good, Myron L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Machine Calculations for the Analysis of the Plane Immobilized Plasma by Trajectories

Description: Abstract: "The analysis of an immobilized plasma by trajectories for the Cartesian case has been adapted to machine calculation and the results of such calculations are described. Their most surprising features is the thinness of the transition layer between a vacuum and a uniform plasma, which is possible without assuming too extreme physical circumstances."
Date: March 8, 1955
Creator: Tonks, Lewi, 1897-1971 & Keirstead, Ralph
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Gravitational-Electromagnetic Torus Models of the Elementary Particles

Description: Abstract: "A torus model of the elementary particles is suggested in which the electron and proton are made stable by gravitational forces derived from the electromagnetic field. It is suggested that the gravitational forces for the unstable particles, presumably the mesons, are not sufficient to keep the torus from expanding in the direction of its large radius. Rest energy zero can be achieved, presumably for photons and neutrons, when the gravitational energy and electromagnetic field energy… more
Date: June 23, 1955
Creator: Bostick, W. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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