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Electromagnetic form factors of hadrons

Description: A vector meson dominance model of the electromagnetic form factors of hadrons is developed which is based on the use of unstable particle propagators. Least-square fits are made to the proton, neutron, pion and kaon form factor data in both the space and time-like regions. A good fit to the low-energy nucleon form factor data is obtained using only rho, $omega$, and phi dominance, and leads to a determination of the vector meson resonance parameters in good agreement with experiment. The nucleo… more
Date: January 1, 1976
Creator: Zidell, V. S.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Important high-twist contribution to prompt single-photon production

Description: Quantitative predictions are presented for a specific hard-scattering reaction ..pi..N ..-->.. ..gamma..X in which both the incident meson and the produced prompt photon couple directly in the QCD amplitude. The process leads to a highly constrained class of events at large p/sub T/ in which the photon momentum is balanced by that of a recoil quark jet, with no spectator jet of final-state particles emerging along the beam axis. Normalized absolutely in terms of the electromagnetic form factor … more
Date: February 1, 1982
Creator: Berger, E. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electromagnetic Structure of Nuclei

Description: A brief review is given of selected topics in the electromagnetic structure of nucleons and nuclei, including nucleon form factors from both quantum chromodynamics and electron scattering data, measurements of the deuteron and triton form factors, quasi-elastic scattering, and the EMC effect. 47 refs., 13 figs. (LEW)
Date: July 1, 1986
Creator: Arnold, R. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Calculation of electromagnetic observables in few-body systems

Description: An introduction to the calculation of electromagnetic observables in few-body systems is given by studying two examples in the trinucleon system: (1) the elastic electron scattering charge form factor in configuration space and momentum space and (2) the two-body photodisintegration of /sup 3/H leading to a neutron-deuteron final state in a separable potential formalism. In the discussion of charge form factor calculations, a number of related topics are touched upon: the relation of structure … more
Date: October 1, 1986
Creator: Gibson, B. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Electrodisintegration of few body systems at SLAC and the Y scaling approach

Description: It is proposed that extraction of the scaling function F(y) from the transverse and longitudinal response functions in inclusive quasi-elastic electron scattering from /sup 3/He and /sup 4/He is a powerful method to either study the validity regime of the impulse approximation by allowing the access to the high nucleon momentum components in these nuclei, or the electromagnetic properties of bound nucleons. 19 refs., 4 figs.
Date: October 1, 1986
Creator: Meziani, Z.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electro- and photonuclear physics with polarized beams and targets

Description: Two long-standing issues in photonuclear physics, the giant M1 resonance in Pb and deuteron photodisintegration, have been studied recently with polarized photons at Urbana and Frascati, respectively. The implications that this work has for settling these key issues will be discussed. In addition, the advantages of the internal polarized target method for electron scattering studies will be discussed and the technology of internal polarized target development will be reviewed. The first results… more
Date: January 1, 1987
Creator: Holt, R.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Perturbative QCD and Electromagnetic Form Factors

Description: We calculate nucleon magnetic form factors using perturbative QCD for several distribution amplitudes including a general one given in terms of Appell polynomials. We find that the magnitude and sign of both nucleon magnetic form factors can be explained within perturbative QCD. The observed normalization of GMp requires that the disturbution amplitude be broader than its superhigh momentum transfer limit, and the GMn/GMp data may require the distrubution amplitude to be asymmetric, in accord w… more
Date: October 1, 1987
Creator: Carlson, Carl & Gross, Franz
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Configuration space Faddeev calculations

Description: The detailed study of few-body systems provides one of the most effective means for studying nuclear physics at subnucleon distance scales. For few-body systems the model equations can be solved numerically with errors less than the experimental uncertainties. We have used such systems to investigate the size of relativistic effects, the role of meson-exchange currents, and the importance of quark degrees of freedom in the nucleus. Complete calculations for momentum-dependent potentials have be… more
Date: January 1, 1989
Creator: Payne, G. L.; Klink, W. H. & Polyzou, W. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Configuration space Faddeev calculations. Progress report, January 1, 1988--December 31, 1988

Description: The detailed study of few-body systems provides one of the most effective means for studying nuclear physics at subnucleon distance scales. For few-body systems the model equations can be solved numerically with errors less than the experimental uncertainties. We have used such systems to investigate the size of relativistic effects, the role of meson-exchange currents, and the importance of quark degrees of freedom in the nucleus. Complete calculations for momentum-dependent potentials have be… more
Date: January 1, 1989
Creator: Payne, G. L.; Klink, W. H. & Polyzou, W. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutrino physics: Summary talk

Description: This paper is organized as follows: First, I describe the state of neutrino phenomenology. Emphasis is placed on sin/sup 2/ /theta//sub W/, its present status and future prospects. In addition, some signatures of ''new physics'' are described. Then, kaon physics at Fermilab is briefly discussed. I concentrate on the interesting rare decay K/sub L/ /yields/ /pi//sup 0/e/sup +/e/sup /minus// which may be a clean probe direct CP violation. Neutrino mass, mixing, and electromagnetic moments are sur… more
Date: April 1, 1989
Creator: Marciano, William J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Color transparency and the structure of the proton in quantum chromodynamics

Description: Many anomalies suggest that the proton itself is a much more complex object than suggested by simple non-relativistic quark models. Recent analyses of the proton distribution amplitude using QCD sum rules points to highly-nontrivial proton structure. Solutions to QCD in one-space and one-time dimension suggest that the momentum distributions of non-valence quarks in the hadrons have a non-trivial oscillatory structure. The data seems also to be suggesting that the intrinsic'' bound state struct… more
Date: June 1, 1989
Creator: Brodsky, Stanley J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Charge Form Factors of the Three- and Four-Body Nuclei

Description: The charge form factors of 3H, 3He, and 4He are calculated using the Monte Carlo method and variational ground-state wave functions obtained for the Argonne two-nucleon and Urbana-VII three-nucleon interactions. The model for the charge density operator contains the two-body exchange contributions of longest range. With some spread due to the uncertainty in the electromagnetic form factors of the nucleon the calculated charge form factors are in good agreement with the empirical values over the… more
Date: January 1, 1990
Creator: Schiavilla, R.; Pandharipande, V.R. & Riska, D.O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monte Carlo methods and applications in nuclear physics

Description: Monte Carlo methods for studying few- and many-body quantum systems are introduced, with special emphasis given to their applications in nuclear physics. Variational and Green's function Monte Carlo methods are presented in some detail. The status of calculations of light nuclei is reviewed, including discussions of the three-nucleon-interaction, charge and magnetic form factors, the coulomb sum rule, and studies of low-energy radiative transitions. 58 refs., 12 figs.
Date: January 1, 1990
Creator: Carlson, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Polarization phenomena in electromagnetic interactions at intermediate energies

Description: Recent results of polarization measurements in electromagnetic interactions at intermediate energies are discussed. Prospects of polarization experiments at the new CW electron accelerators, as well as on upgraded older machines are outlined. It is concluded that polarization experiments will play a very important role in the study of the structure of the nucleon and of light nuclei. 72 refs.
Date: January 1, 1990
Creator: Burkert, V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Spin observables and electromagnetic excitations of nucleon resonances

Description: We discuss the theoretical problems involved in relating the {gamma}N {yields} {pi}N and N(e,e{prime}{pi}) data to the {gamma}N {yields} {Delta}, N* transition form factors. The experimental accuracies needed to explore {gamma}N {yields} {Delta} E2 and charge form factors from p(e,e{prime}{pi}{sup 0}) spin observables A{sub TT} and A{sub TL} are presented. 4 refs., 1 fig.
Date: January 1, 1991
Creator: Lee, T.S.H. (Argonne National Lab., IL (USA)) & Nozawa, S. (Queen's Univ., Kingston, ON (Canada))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Current conservation and electromagnetic interaction currents for non-relativistic systems

Description: It is shown how to construct non-relativistic interaction currents which satisfy current conservation. The construction permits the use of different electromagnetic form factors for the pion, nucleon, and contact contributions, and therefore also permits the use of either G{sub E} of F{sub 1}. The numerical importance of this freedom for calculations of the electromagnetic form factors of {sup 3}He is studied, and found to be significant in some cases.
Date: May 1, 1991
Creator: Gross, Franz & Gross, Franz
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electromagnetic wave scattering from magnetic fluctuations in tokamaks

Description: Cross sections are calculated for electromagnetic wave scattering and mode transformation from magnetic and density fluctuations in the vicinity of the principal electron cutoffs and resonances in a homogeneous plasma. For the special case of scattering perpendicular to the magnetic field, density fluctuations scatter ordinary to ordinary and extraordinary to extraordinary modes -- but cannot transform these modes. On the other hand, magnetic fluctuations perpendicular to the field can transfor… more
Date: July 1, 1991
Creator: Vahala, L. (Old Dominion Univ., Norfolk, VA (United States). Dept. of Electrical and Computer Engineering); Vahala, G. (College of William and Mary, Williamsburg, VA (United States). Dept. of Physics) & Bretz, N. (Princeton Univ., NJ (United States). Plasma Physics Lab.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of the ratio of the real to the imaginary part of the forward nuclear amplitude for p p elastic scattering at radical s = 1. 8 TeV

Description: Experiment E710 at Fermilab has measured the ratio of the real to the imaginary part of the forward nuclear elastic scattering amplitude, {rho}, for {bar p}p elastic scattering at {radical}s = 1.8 TeV. The result is {rho}=0.140{plus minus}.069. 5 refs., 4 figs.
Date: October 1, 1991
Creator: Shukla, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Nonlocal Condensates and QCD Sum Rules for the Pion Form Factor

Description: We extend the QCD sum rule analysis of the pion electromagnetic form factor F(sub)pi(Q^2) into the region of moderately large momentum transfers 3GeV^2 < Q^2 < 10 GeV^2, where one should take into account the effects due to nonzero average virtuality of the vacuum quarks and gluons.
Date: October 1, 1991
Creator: Radyushkin, Anatoly & Radyushkin, Anatoly
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Monte Carlo calculations of few-body and light nuclei

Description: A major goal in nuclear physics is to understand how nuclear structure comes about from the underlying interactions between nucleons. This requires modelling nuclei as collections of strongly interacting particles. Using realistic nucleon-nucleon potentials, supplemented with consistent three-nucleon potentials and two-body electroweak current operators, variational Monte Carlo methods are used to calculate nuclear ground-state properties, such as the binding energy, electromagnetic form factor… more
Date: January 1, 1992
Creator: Wiringa, R.B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theoretical aspects of lepton-hadron scattering

Description: In this paper, I will emphasize two points on Theoretical Aspects of Lepton-Hadron Scattering: (1) The crucial importance of testing the exact'' sum rules as tests of the local current algebra. Discrepancies, if found, between experiment and theory cannot be interpreted away'' in terms of more complex parton wave functions for the hadronic ground state. The three sum rules of interest are those of Adler, Bjorken, and Gross and Llewellyn-Smith. (2) An understanding of the corrections to scaling … more
Date: January 1, 1992
Creator: Drell, S.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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