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Description: The differential cross section for charge-exchange scattering of negative pions by hydrogen has been observed at 230, 260, 290, 317, and 371 Mev. The reaction was observed by detecting one gamma ray from the {pi}{sup 0} decay with a scintillation-counter telescope.
Date: March 18, 1960
Creator: Caris, John C
Partner: UNT Libraries Government Documents Department

Properties of the eta prime meson

Description: The {eta}'(958) meson has been studied in the reaction K{sup -}p {yields} {Lambda}{eta}', with K{sup -} beam momenta ranging from 1.70 to 2.65 Gev/c. The Dalitz plots of {eta}' decay into {pi}{sup +}{pi}{sup -}{eta} and {pi}{sup +}{pi}{sup -}{gamma} have been examined, and from them we have determined that the most likely quantum numbers of the {eta}' are I{sup G}J{sup P} = 0{sup +}0{sup -}, although J{sup P} = 2{sup -} cannot be completely ruled out. They have also shown that the decay into {pi}{sup +}{sup -}{gamma} is mediated by the decay {eta}' {yields} {rho}{sup o}{gamma}. An examination of the production process has yielded further evidence for the J{sup P} = 0{sup -} assignment and suggested that the process takes place via K*(891) exchange in the t channel. Branching fractions and cross sections have been determined, and finally a search for a negatively charged {eta}' in the deuterium reaction K{sup -}d {yields} p{Lambda}{eta}' has confirmed the I = 0 assignment for the {eta}'.
Date: June 4, 1969
Creator: Rittenberg, Alan
Partner: UNT Libraries Government Documents Department

Strange-Particle Production by 1170-MeV/c pi- Mesons

Description: Production of {Lambda} + K{sup 0}, {Sigma}{sup 0} + K{sup 0}, and {Sigma}{sup -} + K{sup +} by 1170-MeV/c {pi}{sup -} mesons has been studied in the Lawrence Radiation Laboratory 72-inch hydrogen bubble chamber, Cross sections, angular distributions, and polarizations are presented. The polarization of the {Sigma}{sup 0} is determined at four center-of-mass angles and found to be small everywhere. Based on published results for the reaction {pi}{sup +} + p {yields} {Sigma}{sup +}, K{sup +}, a comparison of the polarizations of {Sigma}{sup +}, {Sigma}{sup -}, and {Sigma}{sup 0} is made from the charge-independence triangle. A conclusion is reached that the {Sigma}{sup -} polarization should be large, and that the {Sigma}{sup -} and {Sigma}{sup +} polarizations should be opposite in sign.
Date: May 27, 1963
Creator: Anderson, Jared Arnold
Partner: UNT Libraries Government Documents Department

Transverse Space-Charge Effects in Circular Accelerators

Description: The particles in an accelerator interact with one another by electromagnetic forces and are held together by external focusing forces. Such a many-body system has a large number of transverse modes of oscillation (plasma oscillations) that can be excited at characteristic frequencies by errors in the external guide field. In Part I we examine one mode of oscillation in detail, namely the quadrupole mode that is excited in uniformly charged beams by gradient errors. We derive self-consistent equations of motion for the beam envelope and solve these equations for the case in which the space-charge force is much less than the external focusing force, i.e., for strong-focusing synchrotrons. We find that the resonance intensity is shifted from the value predicted by the usual transverse incoherent space-charge limit; moreover, because the space-charge force depends on the shape and size of the beam, the beam growth in always limited. For gradient errors of the magnitude normally present in strong-focusing synchrotrons, the increase in beam size is small provided the beam parameters are properly chosen; otherwise the growth may be large. Thus gradient errors need not impose a limit on the number of particles that can be accelerated. In Part II we examine the other modes of collective oscillation that are excited by machine imperfections. For simplicity we consider only one-dimensional beams that are confined by harmonic potentials, and only small-amplitude oscillations. The linearized Vlasov and Poisson equations are used to find the twofold infinity of normal modes and eigenfrequencies for the stationary distribution that has uniform charge density in real space. In practice, only the low-order modes (the dipole, quadrupole, sextupole, and one or two additional modes) will be serious, and the resonant conditions for these modes are located on a tune diagram. These results, which are valid for all beam intensities, ...
Date: October 30, 1968
Creator: Sacherer, Frank James
Partner: UNT Libraries Government Documents Department


Description: The electron flux spectrum resulting from the slowing down of electrons from /sup 64/Cu uniformly distributed in Cu was measured from 0.1 ev to 37 kev for both a plane disk source and a black body cavity source. The cavity source consisted of a hollow Cu frustrum with walls infinitely thick for /sup 64/Cu beta rays. A matching thick cover allowed only electrons from inside the cavity to enter the Keplertron, a spherical electrostatic beta spectrometer. The cavity data agreed well from 1 kev to 37 kev with a simplified calculation of the Spencer-Fano theory. Below 1 kev, the experimental flux exceeded the calculated flux by as much as 35% at 30 ev. A stopping power derived from proton dath was used in the theory for electrons below 5.5 kev. A buildup of several orders of magnitude in the electron flux below 1 kev was observed. The disk data was lower than the cavity data at all energies above 1 kev, the former approaching the latter at higher energies. The beth spectrometer was calibrated for transmission and resolution from 1.5 ev to 3 kev using an isotropic electron gun and at 31.4 kev using the /sup 152/Sm Auger line. (auth)
Date: May 1, 1964
Creator: McConnell, W.J.; Hubbell, H.H. Jr. & Birkhoff, R.D.
Partner: UNT Libraries Government Documents Department


Description: No Description Available.
Date: January 1, 1967
Creator: Wright, H.A. & Snyder, W.S.
Partner: UNT Libraries Government Documents Department


Description: Thesis submitted to Univ. of Tennessee, Knoxville. Statistical methods were used in an attempt to determine the effect of the tendency to report accidents on the systemic variance in minor injury data over a 6-yr period. The population surveyed included 245 journeymen of 9 skilled craft groups continuously employed during the period. Results indicate that injury and non- injury visits to the dispensary were relatively stable during the 6-yr period and that there was a significant positive relation between non-occupational and injury visits during the period of study. (C.H.)
Date: February 1, 1964
Creator: Sergent, J.E.
Partner: UNT Libraries Government Documents Department


Description: The salivary gland chromosomes of Chironomus tentans larvae collected from White Oak Creek, an area contaminated by radioactive waste from the Oak Ridge National Laboratory, and from six uncontaminated areas were examined for chromosomal aberrations. White Oak Creek populations were exposed to absorbed doses as high as 230 rads per year or about 1000 times background. Chromosomal maps were constructed to make a general comparison of the banding pattern of the salivary chromosomes of the C. tentans in the East Tennessee area with those of Canada and Europe. These maps were used as a reference in scoring aberrations. Fifteen different chromosomal aberrations were found in 365 larvae taken from the irradiated population as compared with five different aberrations observed in 356 larvae from six control populations, but the mean number of aberrations per larva did not differ in any of the populations. The quantitative amount of heterozygosity was essentially the same in the irradiated and the control population, but there were three times the variety of chromosomal aberrations found in the irradiated area. From this evidence it was concluded that chronic low-level irradiation from radioactive waste was increasing the variability of chromosomal aberrations without significantly increasing the frequency. It was also concluded that chromosomal polymorphism can be maintained in a natural population without superiority of the heterozygous individuals. (C.H.)
Date: January 29, 1964
Creator: Blaylock, B G; Auerbach, S I & Nelson, D J
Partner: UNT Libraries Government Documents Department

Design and Properties of a Neon Filled Spark Chamber in a Magnetic Field

Description: Introduction: Recently a new type of charged particle detector, the so-called spark chamber, has been developed. The detector has certain advantages in high energy physics over bubble chambers aside from its much lower cost.
Date: May 1, 1961
Creator: Heyn, Maarten P.
Partner: UNT Libraries Government Documents Department