Download or read book Probing Nucleon Structure with Meson Electro production in Hall C written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Meson electro-production is used in Hall C at Jefferson Lab to probe nucleon, baryon and nuclear structure. The experimental program in Hall C includes studies of semi-inclusive pion production, p, d(e, e'[pi]±)X, where low energy factorization has been observed, suggesting that these reactions can be used to probe nucleon structure, including transverse momentum distributions of quarks, at energies available at JLab after the upcoming 12 GeV upgrade.

Download or read book Exclusive Backward Angle Omega Meson Electroproduction written by Wenliang Li and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exclusive meson electroproduction at different squared four-momenta of the exchanged virtual photon, Q^2 , and at different four-momentum transfers, t and u, can be used to probe QCD's transition from hadronic degrees of freedom at the long distance scale to quark-gluon degrees of freedom at the short distance scale. Backward-angle meson electroproduction was previously ignored, but is anticipated to offer complimentary information to conventional forward-angle meson electroproduction studies on nucleon structure. This work is a pioneering study of backward-angle omega cross sections through the exclusive 1H(e, e' p)omega reaction using the missing mass reconstruction technique. The extracted cross sections are separated into the transverse (T), longitudinal (L), and LT, TT interference terms. The analyzed data were part of experiment E01-004 (Fpi-2), which used 2.6-5.2 GeV electron beams and HMS+SOS spectrometers in Jefferson Lab Hall C. The primary objective was to detect coincidence pion in the forward-angle, where the backward-angle omega events were fortuitously detected. The experiment has central Q2 values of 1.60 and 2.45 GeV2 , at W = 2.21 GeV. There was significant coverage in phi and epsilon, which allowed separation of sigma_T,L,LT,TT . The data set has a unique u coverage of −u ∼ 0, which corresponds to −t > 4 GeV2 . The separated sigma_T result suggest a flat ∼ 1/Q^1.33±1.21 dependence, whereas sigma_L seems to hold a stronger 1/Q^9.43±6.28 dependence. The sigma_L/sigma_T ratio indicate sigma_T dominance at Q2 = 2.45 GeV2 at the ∼90% confidence level. After translating the results into the −t space of the published CLAS data, our data show evidence of a backward-angle omega electroproduction peak at both Q2 settings. Previously, this phenomenon showing both forward and backward-angle peaks was only observed in the meson photoproduction data. Through comparison of our sigma_T data with the prediction of the Transition Distribution Amplitude (TDA) model, and signs of sigma_T dominance, promising indications of the applicability of the TDA factorization are demonstrated at a much lower Q2 value than its preferred range of Q2 > 10 GeV2. These studies have opened a new means to study the transition of the nucleon wavefunction through backward-angle experimental observables.

Download or read book Nuclei as Probes of Meson nucleon Interactions at High and Low Energy written by Gary Howell and published by . This book was released on 2013 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation explores two main topics: 1) Color Transparency and quasi-elastic knockout reactions involving pions and [rho] mesons; and 2) determination of the J/[psi]-nucleon scattering amplitude and scattering length via J/[psi] electroproduction on the deuteron. It is shown that at the energies available at the COMPASS experiment at CERN, Color Transparency should be detectable in the reaction [pi]+A --> [pi]+p+(A-1)* (proton knockout). It is also shown that Color Transparency should be detectable in the electroproduction reaction [gamma]*+A --> [rho]+p+(A-1)* at small Q2 (where Q2 is the virtuality of the photon) but large t (4-momentum transfer squared to the knocked out proton), which represents an as-yet unexplored kinematic region in the search for CT effects in electroproduction of vector mesons. Calculations are also presented for the reaction [gamma]*+D --> J/[psi]+p+n at JLab energies in order to determine the feasibility of measuring the elastic J/[psi]-nucleon scattering amplitude and/or scattering length. It is found that it may be possible to measure the J/[psi]-nucleon scattering amplitude at lower energies than previous measurements, but the scattering length cannot be measured.

Download or read book Excited Nucleons and Hadronic Structure written by V. Burkert and published by World Scientific. This book was released on 2001 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt: The conference NSTAR 2000 was part of a series of conferences and workshops that began in New York in 1988. Since then, the field of excited nucleons and hadron structure has developed enormously, and the scope has broadened. Most significantly, new experimental facilities have come into operation, allowing precise measurements of resonance couplings and transition form factors. The search for ?missing? quark model states and gluonic excitations in complex hadronic channels is now possible.On the theory side, new and promising developments have emerged: quark models with meson degrees of freedom, hybrid baryon models, and studies of baryons in the limit of many colors. For the first time, lattice QCD has been employed to calculate masses of excited nucleons. Nucleon resonances are now recognized as providing significant contributions to the nucleon spin sum rules, as well as the Gerasimov-Drell-Hearn and Bjorken integrals, at finite momentum transfer.

Download or read book Studies of Nucleon Resonance Structure in Exclusive Meson Electroproduction written by and published by . This book was released on 2013 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the International Symposium on Meson Nucleon Physics and the Structure of the Nucleon written by and published by . This book was released on 2002 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Frontier 96 Nuclear Physics Frontiers With Electroweak Probes Proceedings Of Xv Rcnp Osaka International Symposium written by Hiroshi Toki and published by World Scientific. This book was released on 1996-10-25 with total page 414 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hard Exclusive Pseudoscalar Meson Electroproduction and Spin Structure of a Nucleon written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Meson Production in Nucleon nucleon Collisions Close to the Threshold written by C. Hanhart and published by . This book was released on 2004 with total page 101 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pseudoscalar Meson Electroproduction Above the Resonance Region written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One principal motivation for studying exclusive reactions is that they provide a new class of observables, called off-diagonal parton distributions, for the internal structure of the nucleon. The study of exclusive reactions provides a probe of nucleon structure complementary to purely inclusive studies. The simplest, and possibly the most promising, type of experiment is exclusive electroproduction of pseudoscalar mesons at small t, and at large Q2 and W. The authors show that using the CLAS spectrometer at JLAB and with beam energies between four and six GeV, they can obtain good quality electroproduction data that will improve their understanding of nucleon structure.

Download or read book Proceedings of the 5th International Symposium on Meson Nucleon Physics and the Structure of the Nucleon written by International Symposium on Meson Nucleon Physics and the Structure of the Nucleon and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Probing Short range Nucleon nucleon Interactions with an Electron ion Collider written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: For this research, we derive the cross section for exclusive vector meson production in high-energy deeply inelastic scattering off a deuteron target that disintegrates into a proton and a neutron carrying large relative momentum in the final state. This cross section can be expressed in terms of a novel gluon transition generalized parton distribution (T-GPD); the hard scale in the final state makes the T-GPD sensitive to the short-distance nucleon-nucleon interaction. We perform a toy model computation of this process in a perturbative framework and discuss the time scales that allow the separation of initial- and final-state dynamics in the T-GPD. We outline the more general computation based on the factorization suggested by the toy computation: In particular, we discuss the relative role of "pointlike" and "geometric" Fock configurations that control the parton dynamics of short-range nucleon-nucleon scattering. With the aid of exclusive J/[psi] production data at the Hadron-Electron Ring Accelerator at DESY, as well as elastic nucleon-nucleon cross sections, we estimate rates for exclusive deuteron photodisintegration at a future Electron-Ion Collider (EIC). Our results, obtained using conservative estimates of EIC integrated luminosities, suggest that center-of-mass energies sNN ~12GeV2 of the neutron-proton subsystem can be accessed. We argue that the high energies of the EIC can address outstanding dynamical questions regarding the short-range quark-gluon structure of nuclear forces by providing clean gluon probes of such "knockout" exclusive reactions in light and heavy nuclei.

Download or read book Proceedings of the Sixth International Symposium on Meson Nucleon Physics and the Structure of the Nucleon written by International Symposium on Meson Nucleon Physics and the Structure of the Nucleon and published by . This book was released on 1995 with total page 233 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 12th International Conference on Meson Nucleon Physics and the Structure of the Nucleon Menu 2010 written by David Armstrong and published by American Institute of Physics. This book was released on 2011-12-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This conference will be of interest to researchers in theoretical and experimental particle and nuclear physics. The proceedings describe recent progress at understanding the structure and interactions of nuclei, and of their building blocks, protons, neutrons, together with mesons. The papers cover the latest experimental and theoretical developments in the field, and identify the opportunities for future directions. Finally, the use of nuclei as a theatre in which to probe the Standard Model of Particle Physics is explored.

Download or read book Recent Results on the Nucleon Resonance Spectrum and Structure from the CLAS Detector written by and published by . This book was released on 2016 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The CLAS detector at Jefferson Lab has provided the dominant part of all available worldwide data on exclusive meson electroproduction off protons in the resonance region. New results on the $\gamma_{v}pN^*$ transition amplitudes (electrocouplings) are available from analyses of the CLAS data and will be presented. Their impact on understanding of hadron structure will be discussed emphasizing the credible access to the dressed quark mass function that has been achieved for the first time by a combined analysis of the experimental results on the electromagnetic nucleon elastic and $N \rightarrow N^*$ transition form factors. We will also discuss further convincing evidences for a new baryon state $N^{\, '}(1720)3/2^+$ found in a combined analysis of charged double pion photo- and electroproduction cross sections off the protons.

Download or read book CERAF 1992 Summer Workshop written by Franz Gross and published by American Institute of Physics. This book was released on 1993 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt: In one of the last general meetings before the CEBAF accelerator is ready for operation in 1994, scientists there presented papers on the physics that will be studied at CEBAF and the equipment that will be used. Particle and nuclear physicists will learn much from this pre... FROM LONG DESCRIPTION

Download or read book Three dimensional Partonic Structure of the Nucleon written by Mauro Anselmino and published by IOS Press. This book was released on 2012 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: The three-dimensional nucleon structure is central to many theoretical and experimental activities, and research in this field has seen many advances in the last two decades, addressing fundamental questions such as the orbital motion of quarks and gluons inside the nucleons, their spatial distribution, and the correlation between spin and intrinsic motion. A real three-dimensional imaging of the nucleon as a composite object, both in momentum and coordinate space, is slowly emerging.This book presents lectures and seminars from the Enrico Fermi School Three-Dimensional Partonic Structure of the Nucleon, held in Varenna,