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An Experimental Test of Time-Reversal Invariance inthePhotodisintegration of the Deuteron

Description: We present data from a measurement of angular distributions of the reaction n + p {yields} {gamma} + d (1a) for neutrons with energies between 300 and 700 MeV. These data are compared with recent data for the inverse reaction {gamma} + d {yields} n + p (1b). Time-reversal invariance implies that apart from a normalization factor the angular distributions should be the same. We find an intriguing discrepancy in the vicinity of the well-known peak in the total cross section of reaction (1b) and apparent agreement elsewhere. The discrepancy occurs in the shape of the angular distributions and does not depend on the normalization of our data or those of the inverse reaction experiments.
Date: September 1, 1969
Creator: Schrock, B.L.; Detoeuf, J.-F.; Haddock, R.P.; Helland, J.A.; Longo, M.J.; Young, K.K. et al.
Partner: UNT Libraries Government Documents Department

Multiperipheral Dynamics.

Description: No Description Available.
Date: January 1, 1969
Creator: Chew, G. F.
Partner: UNT Libraries Government Documents Department

Momentum Spectra of Charged Pions Produced in Proton-ProtonInteractions between 13 and 28.5 GeV/c

Description: Proton-proton interactions with four or more charged particles in the final state are studied over a range of incident momenta between 13 and 28.5 GeV/c. Topology cross sections are presented. The center-of-mass momentum distributions of {pi}{sup +} and {pi}{sup -} are determined and are successfully parameterized. The {pi}{sup +} and {pi}{sup -} momentum spectra are found to have approximately the same shape. Multiple fireball production is not required by our data.
Date: August 1, 1969
Creator: Smith, Dennis B.; Sprafka, Robert J. & Anderson, Jared A.
Partner: UNT Libraries Government Documents Department


Description: The synthesis of flexible biradical strain-gauges which could be anchored onto two sites of a deformable biological structure had been attempted. Qualitative relationships between the possible conformations of the biradicals and the observed ESR spectra provide guidelines for further synthetic work. Some of the nitroxides synthesized and characterized are: R-CO-R{sub 1}-N-(CH{sub 2}){sub n}-R{sub 2}-N-CO-R, where R is 1-oxyl-2,2,6,6-tetramethyl pyrroline bonded at the 3-position, n = 2,3 and R{sub 1,2} = -H; -C{sub 18}{sub 37}; -CH{sub 2}COOH; -CH{sub 2}COOC{sub 2}H{sub 5}; -CH{sub 2}CONH(CH{sub 2}){sub 2}N(CH{sub 3}){sub 2}; -CH{sub 2}CONH(CH{sub 2}){sub 2}N{sup +}(CH{sub 3}) -CH{sub 2}CO-imidazolide.
Date: November 1, 1969
Creator: Ferruti, P.; Gill, D.; Klein, M.P.; Wang, H.H.; Entine, G. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Fields and First Order Perturbation Effects in Two-DimensionalConductor Dominated Magnets

Description: General expressions are given for the field and its expansion coefficients produced by a two dimensional conductor structure surrounded by iron with a circular inside boundary. Saturation effects are described in terms of the tangential field at that boundary. The effects of the following types of perturbations are discussed: displacement, rotation and error excitation of a conductor, change of conductor shape, and modification of the inside contour of the iron. A design criterion is given to minimize the error fields associated with a displacement of the iron shell relative to the conductor structure. Expressions for the force and torque acting on a conductor are derived both for the unperturbed and perturbed magnet. Formulae are presented that allow convenient and fast evaluation of pertinent quantities with a computer when the structure is too complicated for hand computations.
Date: July 1, 1969
Creator: Halbach, K.
Partner: UNT Libraries Government Documents Department

First Order Perturbation Effects in Iron-Dominated Two-DimensionalSymmetrical Multipoles

Description: The effects of several perturbations are investigated. They are: modification of the shape of a pole, error excitation, displacement, and rotation of a pole. The effects are described in terms of changes of multipole coefficients. General relationships between some of these coefficients are described, and formulae are derived that allow their calculation for a model 2N-pole magnet. Numerical values of these coefficients are given for a quadrupole, sextupole, and octupole.
Date: April 1, 1969
Creator: Halbach, K.
Partner: UNT Libraries Government Documents Department


Description: An electromagnetic search for magnetic monopoles of the minimum size predicted by Dirac, or of any larger magnitude, has been performed on 8.37 kilograms of lunar surface material returned by the Apollo 11 crew. No monopole was found. This experiment sets new limits on the production cross section for monopoles, and on their occurrence in cosmic radiation.
Date: December 1, 1969
Creator: Alvarez, Luis W.; Eberhard, Philippe H.; Ross, Ronald R. & Watt,Robert D.
Partner: UNT Libraries Government Documents Department


Description: A review of methods for static-field compression of an electron ring is shown to suggest advantages for a method in which there is no axial acceleration or deceleration of the ring. In the method proposed here the static magnetic field itself is o such a character that the electrons are neither focused nor defocused in the axial direction. The integrity and movement of the ring through the compressor is controlled by a small traveling magnetic well. The feasibility of creating such a traveling well is discussed, and an example is presented of a current distribution capable of producing the static magnetic field of the compressor.
Date: February 20, 1969
Creator: Laslett, L.Jackson & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department


Description: When particle physics is a closed subject which has been condensed into a text book, the material will surely be organized by concepts and not according to what fact was learned on what accelerator. But short of that day facilities must be designed, planned, and developed, and experiments must be executed on one of a number of available accelerators; and a very necessary point of view is to ask what physics can be done with one facility, in contrast to another. It is in this spirit that, in this note, we look at electron colliding beam devices. In the first section we discuss the physics that can be done with colliding electron beams. After some general remarks we review the experiments already performed, and then turn to experiments planned for the future. The physics that can be done with any accelerator is a strong function of the physics of the accelerator. Every reader of this Journal knows what determines the energy of an accelerator, but the physics that determines the beam intensity, quality, and pulse length is perhaps not so well known. In fact, we plan to devote a future Comment to the physics that limits the performance of conventional accelerators. In the second section of this note, we discuss the physics of colliding electron ring devices. Even more so than in conventional accelerators, the performance of colliding-beam devices is dominated by the physics of the machine, and hence our lengthy second section. But we trust it will be interesting, for the physics is subtle and there is beauty in it.
Date: November 18, 1969
Creator: Pellegrini, Claudio & Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department


Description: Diverse methods proposed for the acceleration of particles by means of collective fields are reviewed. A survey is made of the various currently active experimental programs devoted to investigating collective acceleration, and the present status of the research is briefly noted.
Date: July 4, 1969
Creator: Sessler, Andrew M.
Partner: UNT Libraries Government Documents Department


Description: Two beam choppers were constructed which produce an approximately square, 20-ns pulse of 3+-MeV electrons out of the best portion of the 300-ns Astron beam or an 8-{micro}s microwave electron linac beam for injection into the electron-ring accelerator (ERA) compressor. The choppers are impedance-matched traveling-wave devices which deflect the beam with equal strength electric and magnetic forces, and are powered with either three-electrode spark gaps or thyratrons and a 20-ns pulse line. The electron beam is biased out of the beam-transport system with a dc magnetic field, and switched into it with the chopper.
Date: February 7, 1969
Creator: Faltens, Andris & Kerns, Cordon.
Partner: UNT Libraries Government Documents Department

Domestic tar sands and potential recovery methods: a review

Description: Present knowledge of United States tar sands, including physical properties, occurrence, reserves, and recovery methods, is reviewed and evaluated. Tar sands are oil-, bitumen-, asphalt-, tar-, or petroleum-impregnated rock from which little hydrocarbon material is recoverable by conventional crude oil production techniques. Tar sand oil has been produced by steam injection and underground combustion techniques and by mining methods. However, efficient application of nonmining recovery techniques is hindered because of difficulties in establishing and maintaining formation permeability. Mining and processing methods being used in or proposed for Canadian commercial operations are also discussed.
Date: January 1, 1969
Creator: Spencer, G. B.; Eckard, W. E. & Johnson, F. S.
Partner: UNT Libraries Government Documents Department