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Proposal to study anti-p induced reactions by means of the 15 foot bubble chamber, i.e.: - anti-p d interactions at 50-GeV/c and 80-GeV/c - anti-p p interactions at 80-GeV/c

Description: As a continuation of the work done at Strasbourg we are proposing to study the {bar p}d interactions at {approx} 50 and {approx} 80 GeV/c and also {bar p}p interactions at {approx}80 GeV/c. The exact values of the momenta are not very crucial although we would like to have the same value ( {approx}80 GeV/c) for the {bar p}d and {bar p}p experiments. Because of the lack of data in this momentum range each of the proposed runs will be interesting by itself as will be seen from the physics discussed below.
Date: June 1, 1975
Creator: Fridman, A. & /Strasbourg, IReS
Partner: UNT Libraries Government Documents Department

Precise Measurement of the Spin-Dependent Transverse Asymmetry in Quasielastic {sup 3}He(e, e{prime}) and the Neutron Magnetic Form Factor

Description: We report a measurement of the transverse asymmetry A-T' in {sup 3}He(e,e') quasielastic scattering with high statistical and systematic precision at Q{sup 2}-values from 0.1 to 0.6 (GeV/c){sup 2}. Using a state-of-the-art Faddeev calculation, the neutron magnetic form factor G{sup n}-M is extracted for Q{sup 2}=0.1 and 0.2 (GeV/c){sup 2} with an experimental uncertainty of less than 2%. The results are in excellent agreement with those recently obtained at NIKHEF and Mainz using a deuterium target.
Date: October 1, 2000
Creator: Collaboration, Jens-Ole Hansen and the JLAB E95-001
Partner: UNT Libraries Government Documents Department

The Argonne laser-driven D target: Recent developments and progress

Description: The first direct measurements of nuclear tensor polarization p{sub zz} in a laser-driven polarized D target have been performed at Argonne. We present p{sub zz} and electron polarization P{sub e} data taken at a magnetic field of 600 G in the optical pumping cell. These results are highly indicative that spin-temperature equilibrium is achieved in the system. To prevent spin relaxation of D and K atoms as well as the molecular recombination of D atoms, the walls of the laser-driven D target are coated with organosilane compounds. We discuss a new coating technique, the {open_quotes}afterwash{close_quotes}, developed at Argonne which has yielded stable atomic fraction results when the coating is exposed to K. We also present new coating techniques for glass and Cu substrates.
Date: November 1, 1997
Creator: Fedchak, J.A.; Bailey, K. & Cummings, W.J.
Partner: UNT Libraries Government Documents Department

Measurement of elastic electron-deuteron scattering at large momentum transfers

Description: Coincidence measurements of elastic electron-deuteron cross-sections have been performed in the range of Q{sup 2} between 0.7 and 6.0 (GeV/c){sup 2}. The extracted values of the deuteron electric structure function [A(Q-squared)] in this kinematic range are presented. Values of the deuteron magnetic structure function [B(Q-squared)] in the range of 0.7 < or = Q-squared < or = 1.3(GeV/c)-squared were also extracted and preliminary values are presented. These data are compared with theoretical predictions of both nucleon-meson and quark-gluon based models.
Date: September 1, 1999
Creator: Gomez, J.
Partner: UNT Libraries Government Documents Department

Ultra-intense, short pulse laser-plasma interactions with applications to the fast ignitor

Description: Due to the advent of chirped pulse amplification (CPA) as an efficient means of creating ultra-high intensity laser light (I > 5{times}10{sup 17} W/cm{sup 2}) in pulses less than a few picoseconds, new ideas for achieving ignition and gain in DT targets with less than 1 megajoule of input energy are currently being pursued. Two types of powerful lasers are employed in this scheme: (1) channeling beams and (2) ignition beams. The current state of laser-plasma interactions relating to this fusion scheme will be discussed. In particular, plasma physics issues in the ultra-intense regime are crucial to the success of this scheme. We compare simulation and experimental results in this highly nonlinear regime.
Date: April 1, 1995
Creator: Wilks, S. C.; Kruer, W. L.; Young, P. E.; Hammer, J. & Tabak, M.
Partner: UNT Libraries Government Documents Department

Measurement of T{sub 20} in elastic electron-deuteron scattering

Description: The authors report on a measurement of the tensor analyzing power T{sub 20} in elastic electron-deuteron scattering in the range of four-momentum transfer from 1.8 to 3.2 fm{sup {minus}1}. Electrons of 704 MeV were scattered from a polarized deuterium internal target. The tensor polarization of the deuterium nuclei was determined with an ion-extraction system, allowing an absolute measurement of T{sub 20}. The data are described well by a non-relativistic calculation that includes the effects of meson-exchange currents.
Date: February 1, 1999
Creator: Bouwhis, M.; Alarcon, R. & Botto, T.
Partner: UNT Libraries Government Documents Department

Proposal to study 50,000 Sigman- n multiprong events at 240-GeV/c by means of the 15 foot bubble chamber

Description: In contrast to the large amount of data accumulated in non strange baryon-baryon interactions, there is only a limited amount of information available on {Sigma}N interactions. As a {Sigma}{sup -}p experiment at 240 GeV/c has already been approved with the 15', we propose to complete this experiment by studying the {Sigma}{sup -}n interactions at the same incident momentum. This will allow us to make a comparison between {Sigma}{sup -}n and {Sigma}{sup -}p reactions and to detect thus the isospin influence on the {Sigma}N interactions. Furthermore, as previous bubble chamber experiments at FNAL have shown that four constraint reactions can be studied, the use of a neutron target will give us access to four constraint final states which cannot be obtained from the {Sigma}{sup -}p experiment. The utilization of a deuteron target will of course complicate somewhat the data analysis. Nevertheless this is a convenient method to study the pure 1=3/2 EN isospin state as {Sigma}{sup +}p experiments are more difficult to carry out than {Sigma}{sup -}n. In a first step we would like to have a statistics corresponding to 50,000 multiprong events, i.e., events having more than two prongs.
Date: January 1, 1975
Creator: Braun, H.; Brick, D.; Fridaman, A.; Gerberm, J.P.; Jegham, E.; Juillot, P. et al.
Partner: UNT Libraries Government Documents Department

Study of the Nuclear Antiquark Sea via p+N --> Dimuons

Description: We propose a precise measurement of the A dependence of the Drell-Yan process for 900 GeV protons on targets of deuterium and calcium using the E605 spectrometer. Emphasis will be placed on the kinematic region M > 4 GeV and x{sub F} > 0.2, where one is most sensitive to beam-valence-quark, target-antiquark annihilation. Such measurements will be very sensitive to the A dependence of the target sea quark distribution in the range 0.05 < x{sub 2} < 0.3, and hence provide important clues about the origin-of the EMC (European Muon Collaboration) effect, and unique information on the general issue of quark distributions in nuclear systems. Only minor modifications (liquid deuterium target, and reduced-size beam dump) of the E605 spectrometer will be required.
Date: January 1, 1986
Creator: Moss, J.; Garvey, G.; Peng, J-C.; Alamos, /Los; McCarthy, R.L.; Brook, /SUNY Stony et al.
Partner: UNT Libraries Government Documents Department

Recent progress in the 3N system including three-nucleon forces

Description: A new single Faddeev equation for the inclusion of a three-nucleon force (3NF) into the three-nucleon (3N) continuum and a new partial wave decomposition of a 3NF is presented. This allows for the first time in momentum space calculations the inclusion of a 3NF in higher angular momenta. The authors present converged calculations including a 3NF up to j{sub max} = 6 for the three-nucleon bound state and j{sub max} = 3 in the 3N continuum, where j is the total nucleon-nucleon angular momentum. Several 3N Hamiltonians are generated based on modern nucleon-nucleon (NN) forces and properly adjusted 3NFs, which give the correct triton binding energy. They are used to analyze recent measurements of spin transfer coefficients in elastic nucleon-deuteron scattering. They show that scales with the triton binding energy, whereas K{sub y}{sup z{prime}z{prime}} does not.
Date: July 1, 1997
Creator: Hueber, D.; Witala, H.; Kamada, H.; Nogga, A. & Gloeckle, W.
Partner: UNT Libraries Government Documents Department

The Lambda Lambda interaction and the reaction Xi plus deuteron goes to neutron plus Lambda plus Lambda{dagger}

Description: Interest in the {Lambda}{Lambda} interaction is partly due to the presence of quark-model predictions for an S = {minus}2 dibaryon, and partly to the interest in the role of the coupling between the {Lambda}{Lambda} and {Xi}{Nu} channels in {Lambda}{Lambda} hypernuclei. This latter effect is expected to be substantially more important than the coupling of the {Nu}{Nu} to the {Nu}{Delta} channel in the S = 0 sector, since the difference in threshold between the {Lambda}{Lambda} and {Xi}{Nu} is only {approx}25 MeV. In the absence of any direct measurement of the {Lambda}{Lambda} amplitude, one must resort to either {Lambda}{Lambda} hypernuclei, or to a reaction with a {Lambda}{Lambda} final-state interaction to determine the {Upsilon}{Upsilon} interaction. In this report the authors present results of a theoretical study of the hypernucleus {sub {Lambda}{Lambda}}{sup 6}He and the reaction {Xi}d {r_arrow} n{Lambda}{Lambda} whereby they examine the sensitivity of the calculations to details of the {Lambda}{Lambda} potential, and the coupling between the {Lambda}{Lambda} and the {Xi}{Nu} channels.
Date: July 1, 1997
Creator: Carr, S.B.; Afnan, I.R. & Gibson, B.F.
Partner: UNT Libraries Government Documents Department

Scattering length measurements from radiative pion capture and neutron-deuteron breakup

Description: The neutron-neutron and neutron-proton {sup 1}S{sub 0} scattering lengths a{sub nn} and a{sub np}, respectively, were determined simultaneously from the neutron-deuteron breakup reaction. Their comparison with the recommended values obtained from two body reactions gives a measure of the importance of three-nucleon force effects in the three-nucleon continuum. In order to check on the result obtained for a{sub nn} from the two-body {pi}{sup {minus}}-d capture reaction, a new measurement was performed at LANL. Preliminary results of the three experiments are given.
Date: July 1, 1997
Creator: Gibson, B. F.; Tornow, W. & Carman, T. S.
Partner: UNT Libraries Government Documents Department

Experimental Tests of the GDH and Other Sum Rules at SLAC

Description: Recent measurements from SLAC of the polarized nucleon structure functions g{sub 1} and g{sub 2} have been used to experimentally test the Bjorken, Ellis-Jaffe, Burkhardt-Cottingham, and Efremov-Leader-Teryaev sum rules. In the future, the SLAC E159 experiment will extend structure function measurements using real photons to 40 GeV, enabling a definitive test of the high energy convergence of the GDH sum rule for both proton and deuteron targets.
Date: June 14, 2005
Creator: Bosted, P.E. & /Massachusetts U., Amherst
Partner: UNT Libraries Government Documents Department

Measurement of the Neutron electric form factor at Q2=0.8 2(GeV\\c)

Description: Nucleon form factors allow a sensitive test for models of the nucleon. Recent experiments utilising polarisation observables have resulted, for the first time, in a model-independent determination of the neutron electric form factor GnE. This method employed an 80% longitudinally polarised, high intensity (10 uA) electon beam (883 MeV) that was quasi-elastically scattered off a liquid deuterium target in the reaction D (e, en)p. A neutron polarimeter was designed and installed to measure the ratio of transverse-to-longitudinal polarisation using neutron scattering asymmetries. This ratio allowed a determination of the neutron elastic form factor, GnE, free of the previous large systematic uncertainties associated with the deuterium wave function. The experiment took place in the A1 experimental hall at MAMI taking advantage of a high resolution magnetic spectrometer. A detailed investigation was carried out into the performance of the neutron polarimeter.
Date: September 30, 2007
Creator: Glazier, Derek
Partner: UNT Libraries Government Documents Department

Proposal to study the k+- charge exchange reactions at high energies

Description: An experiment is proposed for measurement of the K{sup {+-}} {yields} K-Long charge-exchange reactions using unseparated beams; useful rates are obtained for p{sub inc}{le}100 GeV/c and -t {le} 1 (GeV/c){sup 2}. A V-spectrometer with resolution {+-}1% is used downstream of the target for detection of the decays K-long {yields} {pi}{sup +}{pi}{sup -}. Using hydrogen and deuterium targets, the detection system is designed to measure: (1) d{sigma}/dt for K{sup -}p {yields} {bar K}{sup 0}n. The reaction will be distinguished from background processes involving N* and K* production by kinematics and supplementary detectors surrounding the target. (2) d{sup 2}{sigma}/dpdt for K{sup -}d {yields} {bar K}{sup 0}nn. This final state will be distinguished from those involving production of {pi}{sup 0}'s or charged particles primarily by the supplementary target veto array. Use of a deuterium target will provide partial clarification of the problems to be encountered in achieving part 3. In principle, some information on the relative sizes of the spin-flip and non-spin-flip amplitudes will be obtained. (3) d{sup 2}{sigma}/dpdt for K{sup +}d {yields} K{sup 0}pp. Since charged particles are produced at the interaction vortex, this final state can be reliably extracted only with the insight gained in parts (1) and (2) and a detailed study of the distributions in the target veto counter array.
Date: February 1, 1971
Creator: Meyer, Stuart L.; Miller, Donald H.; Hicks, George & U., /Northwestern
Partner: UNT Libraries Government Documents Department

Proposal for mu p scattering experiment at NAL

Description: It is proposed to use a muon beam at NAL to study inelastic scattering. The muon beam will have an energy 100 {+-} 2.5 GeV, with 10{sup 6} instantaneous, 3 x 10{sup 5} average, muons per second. If a beam of 10{sup 7}/sec becomes available it is possible that improved technology will immediately allow its use. The scattered muons and the electro-produced hadrons will be detected in a spectrometer system consisting of a large magnet equipped with a set of wire spark chambers and scintillation counters. It is proposed to use both hydrogen and deuterium targets, of length 200 cms. The experiment has in particular the following goals: (1) Measure the structure function W{sub 2}(q{sup 2}, {upsilon}) over the range 20 GeV < {upsilon} < 90 GeV, and 0.2 < q < 20 (GeV/c){sup 2}. (2) Study rho electroproduction in such a manner as to obtain the density matrix elements as a function of q{sup 2}, t, and {upsilon}. (3) Study the momentum spectrum and multiplicity of the electro-produced hadrons. (4) Use the recoil protons to make a study of the electroproduction of forward going mesons. It is estimated that these measurements will require 800 hours of running time.
Date: June 1, 1970
Creator: Kirk, T.; Pipkin, F.M.; russell, J.; Tannenbaum, M.; Wilson, Richard; Sanderson, J. et al.
Partner: UNT Libraries Government Documents Department

MEETING IX - BEVATRON RESEARCH CONFERENCE--BEVATRON PHYSICS

Description: A large number of experiments relating to nuclear structure and materialization of energy will fall within the energy range of primary and secondary particles available from the Bevatron. Some experiments of interest are outlined below with pertinent comments. Proton-proton scattering can be extended to the high energy range using liquid hydrogen targets and hydrogenous materials by bombarding the target with the internal beam or using externally scattered protons. Proton-deuteron scattering measurements using liquid deuterium targets or solid materials can also be extended. Proton scattering from heavier nuclei may be found less difficult to interpret at these level energies as the nucleons will interact more or less independently. The wavelength of the bombarding particles will now be much smaller than nucleon diameters. Nuclear collisions represent by far the most important interaction between high energy nucleons and matter. Proton-neutron charge exchange interaction within the internal target will provide an external flux of neutrons which can be used directly for total nuclear cross section measurements and neutron-proton scattering. Low energy measurements, say below 200 Mev; show that nuclear interaction cross sections do not go down as 1/{lambda} as reactions become predominantly nuclear rather than electromagnetic. Measurements can now be extended into the Bev range to investigate the complex as opposed to the point charge concept of nuclear interactions. The external neutron beam may also provide high energy protons in charge exchange interactions with external targets. Mesons produced in the internal target will provide external meson beams of all types for cross section measurements over a large range of energies. Sufficient energy will be available for production of V particles with reasonable cross sections. The primary event leading to the production of V particles and the characteristic mode of decay can be studied. These events are best adapted to cloud chamber techniques wherein co-planer ...
Date: December 15, 1953
Creator: Karplus, Robert
Partner: UNT Libraries Government Documents Department

A study of CR-39 track response to charged particles from NOVA implosions

Description: We have exposed CR-39 track recording material to a number of NOVA implosions. Radiation from the implosion passed through an array of ranging filters, which aided identification of the incident particles and their energies. The etching procedure was calibrated by including a piece of track exposed to DD protons from a small accelerator. For the same shots, we quantitatively compare the DD neutron yield with the DD proton yield determined from the track. In DT implosions, tracks produced by neutron interactions prevent observation of charged-particle tracks that are produced by the processes of knock-on, secondary or tertiary fusion.
Date: June 14, 1996
Creator: Phillips, T.W.; Cable, M.D.; Hicks, D.G.; Li, C.K.; Petrasso, R.D. & Seguin, F.H.
Partner: UNT Libraries Government Documents Department

Nucleon spin structure functions from HERMES: The first year

Description: HERMES, {und HE}RA {und Me}asurement of {und S}pin, is a second generation exper to study the spin structure of the nucleon by using polarized internal gas targets in the HERA 28 GeV electron storage ring. Scattered positrons and coincident hadrons are detected in an open geometry spectrometer which includes particle identification. Inclusive data with polarized {sup 3}He give the spin structure function {ital g{sup n}{sub 1}(x)} and the Ellis-Jaffe integral RR{Lambda} = {integral}{sub 0}{sup 1} {ital g{sup n}{sub 1}(x)dx} for the neutron. The semi-inclusive spin asymmetries are a unique and sensitive probe of the flavor dependence of quark helicity distributions and properties of the quark sea. Data taken in 1995 with unpolarized hydrogen and deuterium targets provide measurements of the flavor distributions of sea and valence quarks. In a preliminary analysis, {Lambda}{sup {ital n}}{sub 1} = -0.032{+-}0. 013{sub {ital stat.}} {+-} O.017{sub {ital syst.}} is obtained at Q{sup 2} = 3(GeV/c){sup 2} for the Ellis-Jaffe integral.
Date: December 31, 1996
Creator: Jackson, H.E. & Collaboration, HERMES
Partner: UNT Libraries Government Documents Department

Low-energy {sup 4}He{sup +} scattering from deuterium adsorbed on stepped Pd(331)

Description: We have taken angle-resolved data for the scattering of low-energy (< I keV) {sup 4}He{sup +} from deuterium adsorbed on a stepped Pd(331) surface. The impact geometry was up the staircase, that is, the {sup 4}He{sup +} beam was perpendicular to and directly incident onto the unshadowed <011>Pd ledge atoms. A strong quasi-elastic scattering signal of {sup 4}He{sup +} from D ({sup 4}He{sup +}/D) was observed at a forward scattering angle of {theta} = 25{degrees} and an incidence angle of {alpha} = 76{degrees} from the (331) normal. The results agree with shadow cone calculations of scattering first from Pd ledge atoms followed by a second event, {sup 4}He{sup +}/D. The resultant adsorption geometry shows D to reside in the quasi- threefold ledge site on the surface directly above the bulk fcc octahedral void. These results are consistent with the previous{sup 4}He{sup +} scattering study of the geometrically related Pd(110)- D(ads) system.
Date: July 1, 1996
Creator: Ellis, W.P. & Bastasz, R.
Partner: UNT Libraries Government Documents Department

Reducing deuterium-tritium ice roughness by electrical heating of the saturated vapor

Description: High gain targets for inertial confinement fusion (ICF) contain a layer of deuterium-tritium (DT) ice which surrounds a volume of DT gas in thermal equilibrium with the solid. The roughness of the cryogenic fuel layer inside of ICF targets is one of the sources of imperfections which cause implosions to deviate from perfect one dimensional performance. Experiments at Lawrence Livermore National Laboratory have shown that applying a heat flux across the inner surface of a hydrogen layer such as that inside an ICF target reduces the intrinsic roughness of the surface. We have developed a technique to generate this heat flux by applying and electric field to the DT vapor in the center of these shells. This vapor has a small but significant conductivity due to ionization caused by beta decay of tritium in the vapor and the solid. We describe here experiments using a 1.15 GHz cavity to apply an electric field to frozen DT inside of a sapphire test cell. The cell and cavity geometry allows visual observation of the frozen layers.
Date: June 14, 1996
Creator: Mapoles, E.R.; Sater, J.D.; Monsler, E. & Pipes, J.
Partner: UNT Libraries Government Documents Department

Electron-deuteron scattering in a relativistic theory of hadrons

Description: The author reviews a three-dimensional formalism that provides a systematic way to include relativistic effects including relativistic kinematics, the effects of negative-energy states, and the boosts of the two-body system in calculations of two-body bound-states. He then explains how to construct a conserved current within this relativistic three-dimensional approach. This general theoretical framework is specifically applied to electron-deuteron scattering both in impulse approximation and when the {rho}{pi}{gamma} meson-exchange current is included. The experimentally-measured quantities A, B, and T{sub 20} are calculated over the kinematic range that is probed in Jefferson Lab experiments. The role of both negative-energy states and meson retardation appears to be small in the region of interest.
Date: November 1, 1998
Creator: Phillips, D.
Partner: UNT Libraries Government Documents Department

Nuclear effects in deep inelastic scattering

Description: The authors extend the approach used to treat quasi-elastic inclusive electron-nucleus scattering to the deep inelastic region. They provide a general approach to describe lepton scattering from an off-shell nucleon, and calculate the ratio of inclusive deep inelastic scattering cross sections to the deuteron for nuclear matter and helium (EMC-effect). They find that the consistent inclusion of the binding effects, in particular the ones arising from the short-range nucleon-nucleon interaction, allows to describe the data in the region of x &gt; 0.15 where binding fully accounts for the deviation of the cross section ratios from one.
Date: March 1, 1998
Creator: Benhar, O.; Pandharipande, V.R. & Sick, I.
Partner: UNT Libraries Government Documents Department