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Measurement of the Polarization in Elastic Electron ProtonScattering

Description: We have measured the (illegible) scattering (?-illegible) of electrons (?-illegible) from a polarized proton target. (illegible) between (?-illegible) imaginary part of the two-photon-(illegible) (illegible) photon-exchange amplitude could produce (?-illegible) (illegible) results indicate no asymmetry within (illegible) 1 to 2% at four(?-illegible)-momentum transfer (illegible) (illegible) 0.98 (GeV/c){sup 2}.
Date: March 1, 1970
Creator: Powell, Thomas; Chamberlain, Owen & Borghini, Michel
Partner: UNT Libraries Government Documents Department

Measurements of Scattering Processes in Negative Ion- Atom Collisions

Description: The main research activity is to study various scattering processes which occur in H{sup -} collisions with atomic (specifically, noble gas and atomic hydrogen) targets in the intermediate energy region. These processes include: elastic scattering, single- and double-electron detachment, and target excitation/ionization.
Date: December 22, 2000
Creator: Kvale, T. J.
Partner: UNT Libraries Government Documents Department

Kinematics of the Relativistic Two-Body Problem

Description: Abstract: "The kinematics of elastic scattering, inelastic scattering, and the two body reaction problem is developed in the relativistic limit and exact expressions obtained for the energies, angles, and solid-angle transformations involved. The results are specialized for zero rest mass of one or more of the particles involved. An outline for the coding of the problem on the I.B.M. Electronic Data Processing Machine, Type 701 is presented."
Date: August 1955
Creator: Blumberg, Leroy & Schlesinger, Stewart I.
Partner: UNT Libraries Government Documents Department

Measurements of elastic and quasi-elastic scatterings of pp and -pp from ~ 20 to 40 GeV/c

Description: We propose a systematic study of elastic and quasi-elastic scatterings of pp and {bar p}p in the forward region (|t{vert_bar} {approx}< 1.5 GeV{sup 2}) from {approx} 20 to 40 GeV/c by using the single-arm spectrometer of NAL Exp. 7 without any essential change. The physics interests in this energy region warrant a precise comparison between pp and {bar p}p as a function of s(t) for fixed t(s). Therefore it is essential to use the same experimental apparatus and analysis procedures in order to minimize possible systematic errors. The possible future experiments at Serpukhov will not be able to produce sufficient flux in the secondary {bar p} beams to answer the physics questions raised in this proposal.
Date: July 1, 1971
Creator: Lai, K.W.; Turkot, F.; Gordon, H.A.; Schublein, P.; /Brookhaven; Cords, D. et al.
Partner: UNT Libraries Government Documents Department

Elastic scattering of low-energy electrons by randomly oriented and aligned molecules: Influence of full non-spherical potentials

Description: Elastic scattering of low (10-50 eV) kinetic energy electrons from free diatomic molecules is studied using a single-center expansion of the full molecular potential. Dynamic exchange and polarization are included in a local form. The calculated elastic differential scattering cross-sections (DCS) for electron impact on CO and N2 are in good agreement with available experimental data. The importance of using the full molecular potential instead of a two-center potential approach is pointed out. These corrections are small for energies above 50 eV, but they become increasingly important at lower energies. When discussing the angular distributions of elastically-scattered electrons from oriented molecules (like surface adsorbates), we show that these corrections are particularly significant. The results have implications for other electron scattering problems such as those encountered in low-energy photoelectron diffraction from both core and valence levels.
Date: July 17, 2000
Creator: Rolles, D.; Diez Muino, R.; Garcia de Abajo, F.J.; Fadley, C.S & Van Hove, M.A.
Partner: UNT Libraries Government Documents Department

SciNOvA: A Measurement of Neutrino-Nucleus Scattering in a Narrow-Band Beam

Description: We propose to construct and deploy a fine-grained detector in the Fermilab NOvA 2 GeV narrow-band neutrino beam. In this beam, the detector can make unique contributions to the measurement of quasi-elastic scattering, neutral-current elastic scattering, neutral-current {pi}{sup 0} production, and enhance the NOvA measurements of electron neutrino appearance. To minimize cost and risks, the proposed detector is a copy of the SciBar detector originally built for the K2K long baseline experiment and used recently in the SciBooNE experiment.
Date: October 15, 2010
Creator: Paley, J.; Djurcic, Z.; /Argonne; Harris, D.; Tesarek, R.; /Fermilab et al.
Partner: UNT Libraries Government Documents Department

Cross section of electron - off-shell nucleon interaction

Description: The results of theoretical calculations of the electron-bound nucleon interaction cross section ({sigma}{sub eN}) are given for four theoretical approaches. It is shown that there are significant differences between predictions of these methods, especially for the deeply bound (high internal momentum, high removing energy) nucleons. To test these predictions experimentally the authors study of cross sections obtained for two primary energies or for bound proton and neutron. These ratios will be insensitive to the nuclear spectral function as well as to the off-shell modifications of the bound nucleon form-factors if every pair of measurements are made for the same values of energy and momentum-transfers, removal energy, internal and final momenta of the struke nucleon. It is shown that dependences of the discussed ratios on various kinematical parameters are significantly different in different approaches and can be used to distinguish the theoretical models used.
Date: January 1, 1993
Creator: Egiyan, K. & Sargsyan, M.
Partner: UNT Libraries Government Documents Department

P-P Elastic and Charge-Exchange Scattering at about 120 Mev

Description: Observation of antiprotons in a propane or hydrogen bubble chamber offers the possiblity of studying several phenomena for which counter or photographic emulsion techniques are less suitable. Because there is a high ratio of pions, muons, and electrons to antiprotons in the available momentum-analyzed beams, these beams cannot be used in the bubble chamber without an initial purification, which increases the ratio of antiprotons to other particles. Such a purification has been achieved by utilizing the difference in rates of momentum loss in absorbers between antiprotons and other particles. The principle of the method is to pass a momentum-analyzed beam through an absorber. Since particles of unequal mass do not have the same specific ionization they lose different amounts of momentum, and a further magnetic deflection suffices to separate the particles physically according to mass. In this experiment a desirable momentum for antiprotons entering the bubble chamber was 684 Mev/c; however, at this momentum the ratio of undesirable particles to antiprotons at the target where they are produced is about 6 x 10{sup 5}. By starting with 970-Mev/c particles at the target and using the method of differential absorption, they decreased the ratio of undesirable particles (87% {mu}{sup -}, 105 {pi}{sup -}, 3% e{sup -}) to antiprotons entering the bubble chamber at 684 Mev/c to 1.5 x 10{sup 4}. A system of counters indicatd when an antiproton entered the bubble chamber, and although the chamber was expanded on every Bevatron pulse, the lights were flashed and the chamber photographed only when an antiproton entered.
Date: March 28, 1958
Creator: Agnew Jr., Lewis; Elioff, Tom; Fowler, William B.; Gilly, Louis; Lander, Richard L.; Oswald, Larry et al.
Partner: UNT Libraries Government Documents Department

Probing the nonlocal approximation to resonant collisions ofelectrons with diatomic molecules

Description: A numerically solvable two-dimensional model introduced bythe authors [Phys. Rev. A 73, 032721 (2006)]is used to investigate thevalidity of the nonlocal approximation to the dynamics of resonantcollisions of electrons with diatomic molecules. The nonlocalapproximation to this model is derived in detail, all underlyingassumptions are specified and explicit expressions for the resonant andnon-resonant (background) T matrix for the studied processes are given.Different choices of the so-called discrete state, which fully determinesthe nonlocal approximation, are discussedand it is shown that a physicalchoice of this state can in general give poorer results than otherchoices that minimize the non-adiabatic effects and/or the backgroundterms of the T matrix. The background contributions to the crosssections, which are usually not considered in the resonant theory ofelectron-molecule collisions, can be significant not only for elasticscattering but also for the inelastic process of vibrationalexcitation.
Date: September 7, 2007
Creator: Houfek, Karel; Rescigno, Thomas N. & McCurdy, C. William
Partner: UNT Libraries Government Documents Department

200-GeV proton-proton elastic scattering at high transverse momentum

Description: This is a proposal to study p-p elastic scattering at the highest possible P{sub {perpendicular}}{sup 2} at NAL, using a CH{sub 2} or H{sub 2} target placed directly in the extracted beam and a double arm spectrometer. We expect to be able to set an upper limit at the level d{sigma}/dt/d{sigma}/dt{sub t=0} {approx} 10{sup -14}. This would be sufficient to determine if there are exactly three regions in the p-p interaction with considerable precision.
Date: June 1, 1970
Creator: Ratner, L.G.; /Argonne; Krisch, A.D.; Roberts, J.B.; Terwilliger, K.M. & U., /Michigan
Partner: UNT Libraries Government Documents Department

Elastic scattering of the long-lived hadrons

Description: The authors propose to measure the elastic scattering of the charged hadrons {pi}{sup {+-}}, K{sup {+-}}, p and {bar p} over a region of momentum transfer up to about 1 GeV/c. Special attention will be given to the Coulomb interference region. This experimental program is based on the use of novel detectors of high spatial resolution which we have developed.
Date: December 1, 1970
Creator: Atac, M.; Dolnick, C.; Gollon, P.; Lach, J.; MacLachlan, J.; Roberts, A. et al.
Partner: UNT Libraries Government Documents Department

One more algorithm for generating elastic and inelastic scattering matrices

Description: Much effort in recent years has been spent on attempts to optimize the numerical problem of calculating elastic and inelastic multigroup scattering matrices from basic ENDF/B data. This paper presents an algorithm which minimizes the amount of data manipulation and approximation required. The algorithm is based on avoiding time-consuming transformations between c.m. and lab coordinates for the differential cross section and the additional requirement with the ETOG algorithm to manufacture Legendre expansion coefficients if tabular distributions are given. The new algorithm was incorporated into the ETOP code, which generates elastic and inelastic scattering matrices for the 68-group Phrog II fast spectrum code. CPU time is roughly a factor of 4 faster than the ETOG algorithm in the most favorable cases for ETOG. (RWR)
Date: January 1, 1975
Creator: Grimesey, R.A.
Partner: UNT Libraries Government Documents Department

Analyzing Power $A_n$ in High P-Transverse Squared Proton-Proton Elestic Scattering

Description: This is a proposal to measure the Analyzing Power $A_n$ in Proton-Proton Elestic Scattering at High P-Transverse Squared of 1 to 12 (GeV/c)<sup>2</sup> using a 120 GeV unpolarized extracted proton beam from Fermilab's Main Injector starting in 2001.
Date: August 1, 1998
Creator: Anferov, V. A.; Blinov, B. B.; Courant, E. D.; Derbenev, Ya. S.; Gladycheva, S. E.; Fidecaro, G. et al.
Partner: UNT Libraries Government Documents Department

Early Measurement of 200 GeV PP Large Angle Elastic Scattering

Description: The proton-proton angular distribution would be determined in the region 4&lt;-t&lt;20 Gev{sup 2} at 200 Gev/c and 10&lt;-t&lt;20 Gev{sup 2} at 400 Gev/c by measuring both scattered protons after magnetic analysis with proportional wire chambers in Proton West. Cross sections as low as {approx}0{sup -38} cm{sup 2} /Gev{sup 2} could be measured with an average beam intensity {approx} 10{double_prime} protons/sec.
Date: January 1, 1972
Creator: Orear, J.; Klems, J.; U., /Cornell; Ryan, D.; Stairs, D.; U., /McGill et al.
Partner: UNT Libraries Government Documents Department