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Full-Text Articles in Quantum Physics
Two-Current Transition Amplitudes With Two-Body Final States, Keegan H. Sherman, Feliipe G. Ortega-Gama, Raúl A. Briceño, Andrew W. Jackura
Two-Current Transition Amplitudes With Two-Body Final States, Keegan H. Sherman, Feliipe G. Ortega-Gama, Raúl A. Briceño, Andrew W. Jackura
Physics Faculty Publications
We derive the on-shell form of amplitudes containing two external currents with a single hadron in the initial state and two hadrons in the final state, denoted as 1 + J → 2 + J . This class of amplitude is relevant in precision tests of the Standard Model as well as for exploring the structure of excited states in the QCD spectrum. We present a model-independent description of the amplitudes where we sum to all orders in the strong interaction. From this analytic form we are able to extract transition and elastic resonance form factors consistent with previous work …
Resonances From Lattice Qcd, Raúl A. Briceño
Resonances From Lattice Qcd, Raúl A. Briceño
Physics Faculty Publications
The spectrum of hadron is mainly composed as shortly-lived states (resonance) that decay onto two or more hadrons. These resonances play an important role in a variety of phenomenologically significant processes. In this talk, I give an overview on the present status of a rigorous program for studying of resonances and their properties using lattice QCD. I explain the formalism needed for extracting resonant amplitudes from the finite-volume spectra. From these one can extract the masses and widths of resonances. I present some recent examples that illustrate the power of these ideas. I then explain similar formalism that allows for …
Ep → Ep Π⁰ Reaction Studied In The Δ(1232) Mass Region Using Polarization Asymmetries, M. Bektasoglu, L. Ciciani, K.V. Dharmawardane, G. E. Dodge, T.A. Forest, C.E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, S. Stepanyan, L. B. Weinstein, Et Al., Clas Collaboration
Ep → Ep Π⁰ Reaction Studied In The Δ(1232) Mass Region Using Polarization Asymmetries, M. Bektasoglu, L. Ciciani, K.V. Dharmawardane, G. E. Dodge, T.A. Forest, C.E. Hyde-Wright, A. Klein, A. V. Klimenko, S. E. Kuhn, S. Stepanyan, L. B. Weinstein, Et Al., Clas Collaboration
Physics Faculty Publications
Measurements of the angular distributions of target and double-spin asymmetries for the Δ+(1232) in the exclusive channel → p(→e,e'p)π0 obtained at the Jefferson Lab in the Q2 range from 0.5 to 1.5 GeV2/c2 are presented. Results of the asymmetries are compared with the unitary isobar model [D. Drechsel , Nucl. Phys. A645, 145 (1999)], dynamical models [T. Sato and T. S. Lee, Phys. Rev. C 54, 2660 (1996); S. S. Kamalov , Phys. Lett. B 27, 522 (2001)], and the effective Lagrangian theory [R. M. Davidson , Phys. Rev. …
Η Photoproduction On The Proton For Photon Energies From 0.75 To 1.95 Gev, M. Bektasoglu, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, S. Stepanyan, J. Yun, Et Al., Clas Collaboration
Η Photoproduction On The Proton For Photon Energies From 0.75 To 1.95 Gev, M. Bektasoglu, K. V. Dharmawardane, G. E. Dodge, C. E. Hyde-Wright, A. Klein, S. E. Kuhn, S. Stepanyan, J. Yun, Et Al., Clas Collaboration
Physics Faculty Publications
Differential cross sections for γp→ηp have been measured with tagged real photons for incident photon energies from 0.75 to 1.95 GeV. Mesons were identified by missing mass reconstruction using kinematical information for protons scattered in the production process. The data provide the first extensive angular distribution measurements for the process above W = 1.75 GeV. Comparison with preliminary results from a constituent quark model support the suggestion that a third S11 resonance with mass ∼1.8 GeV couples to the ηN channel.