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Related papers: Virtual Compton Scattering

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We study the timelike virtual Compton scattering process with a linearly polarized photon beam, in the generalized Bjorken scaling region and in the medium energy range which will be studied intensely at JLab12 experiments. We define new…

High Energy Physics - Phenomenology · Physics 2015-06-19 A. T. Goritschnig , B. Pire , J. Wagner

Virtual Compton Scattering (VCS) at low transferred momenta to the proton ($t$) and sufficiently high c.m. energies ($s$) may be used to a) study $Q^2$--dependence of leading $t$--channel exchanges and b) look for onset of scaling behavior…

High Energy Physics - Phenomenology · Physics 2007-05-23 Andrei Afanasev

Real Compton Scattering on the proton in the hard scattering regime is investigated. Recent theoretical developments are reviewed. Plans for new experimental studies at Jefferson Laboratory are presented.

High Energy Physics - Phenomenology · Physics 2007-05-23 Alan M. Nathan

Deeply virtual Compton scattering is a fascinating process which can provide a tomographic view of nuclei and bound nucleons. The first experimental results for $^4$He targets, recently released at Jefferson Lab, have been analyzed here in…

Nuclear Theory · Physics 2021-02-03 Sara Fucini , Sergio Scopetta , Michele Viviani

We discuss the virtual Compton scattering reaction $e^-p\to e^-p\gamma$ at low energies. We present results for the generalized polarizabilities of the nucleon obtained in heavy baryon chiral perturbation theory at $O(p^3)$.

High Energy Physics - Phenomenology · Physics 2009-10-30 T. R. Hemmert , B. R. Holstein , G. Knoechlein , S. Scherer

Threshold photon electroproduction off the proton allows one to measure new electromagnetic observables which generalise the usual polarisabilities. There are -- a priori -- ten "generalised polarisabilities", functions of the virtual…

Nuclear Theory · Physics 2010-02-17 P. A. M. Guichon , G. Q. Liu , A. W. Thomas

Absolute differential cross sections for the reaction (e+p -> e+p+gamma) have been measured at a four-momentum transfer with virtuality Q^2=0.33 GeV^2 and polarization \epsilon = 0.62 in the range 33.6 to 111.5 MeV/c for the momentum of the…

High Energy Physics - Experiment · Physics 2008-11-26 The VCS , A1 collaboration

We derive two relations involving spin polarizabilities of a spin-1/2 particle and consider their empirical implications for the proton. Using the empirical values of the proton anomalous magnetic moment, electric and magnetic charge radii,…

Nuclear Theory · Physics 2015-04-01 Vladimir Pascalutsa , Marc Vanderhaeghen

Virtual Compton Scattering is studied at the Thomas Jefferson National Accelerator Facility in the energy domain below pion threshold and in the Delta(1232) resonance region. The data analysis is based on the Dispersion Relation (DR)…

High Energy Physics - Phenomenology · Physics 2007-05-23 The Jefferson Lab Hall A Collaboration , G. Laveissiere

We propose to conduct a measurement of the Virtual Compton Scattering reaction in Hall C that will allow the precise extraction of the two scalar Generalized Polarizabilities (GPs) of the proton in the region of $Q^2=0.05~(GeV/c)^2$ to…

We calculate timelike virtual Compton scattering amplitudes in the generalized Bjorken scaling regime and focus on a new polarization asymmetry in the scattering process with a linearly polarized photon beam in the medium energy range,…

High Energy Physics - Phenomenology · Physics 2014-07-09 A. T. Goritschnig , B. Pire , Jakub Wagner

We report on new measurements of the electric Generalized Polarizability (GP) of the proton $\alpha_E$ in a kinematic region where a puzzling dependence on momentum transfer has been observed, and we have found that $\alpha_E = (5.3 \pm…

We investigate the extension of the deeply virtual Compton scattering process into the weak interaction sector.

High Energy Physics - Phenomenology · Physics 2014-11-18 Ales Psaker

We discuss low-energy virtual Compton scattering off the proton within the framework of a nonrelativistic constituent quark model. A simple interpretation of the spin-averaged generalized polarizabilities is given in terms of the induced…

Nuclear Theory · Physics 2017-08-23 B. Pasquini , S. Scherer , D. Drechsel

Using the techniques of chiral effective field theories we evaluate the so called generalized polarizabilities of the nucleon, which characterize the structure dependent components in virtual Compton scattering (VCS) as probed in the…

Nuclear Theory · Physics 2009-10-31 T. R. Hemmert , B. R. Holstein , G. Knoechlein , D. Drechsel

We analyse deeply-virtual Compton scattering on a proton target, gamma* P -> P' gamma in the backward region and in the scaling regime. We define the transition distribution amplitudes which describe the proton to photon transition.…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. P. Lansberg , B. Pire , L. Szymanowski

We calculate polarization phenomena for virtual Compton scattering on protons, at relatively large momentum transfer 1 GeV$^2$ $\le -q^2\le$ 5 GeV$^2$ on the basis of a model for $\gamma^*+ p\to \gamma+p$ with two main contributions:…

Nuclear Theory · Physics 2007-05-23 M. P. Rekalo , E. Tomasi-Gustafsson

The status of realistic calculations of nuclear generalized parton distributions, entering the theoretical description of coherent deeply virtual Compton scattering off nuclei, is reviewed for trinucleons and for $^4$He, also in view of…

Nuclear Theory · Physics 2019-10-18 Sara Fucini , Matteo Rinaldi , Sergio Scopetta

We study low-energy virtual Compton scattering off the proton within the framework of a nonrelativistic constituent quark model. The Compton tensor is divided into two separately gauge-invariant contributions. The first consists of the…

Nuclear Theory · Physics 2011-07-19 B. Pasquini , S. Scherer , D. Drechsel

Virtual Compton Scattering is studied at the Thomas Jefferson National Accelerator Facility at low Center-of-Mass energies, below pion threshold. Following the Low Energy Theorem for the $ ep \to ep \gamma$ process, we obtain values for the…

High Energy Physics - Phenomenology · Physics 2013-05-29 The Jefferson Lab Hall A Collaboration , S. Jaminion