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Related papers: Separation of Quark Flavors using DVCS Data

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We argue that deeply virtual Compton scattering will display Regge behavior nu^alpha_R(t) at high energy at fixed-t, even at high photon virtuality, not necessarily conventional scaling. A way to see this is to track the Reggeon…

High Energy Physics - Phenomenology · Physics 2009-07-01 Stanley J. Brodsky , Felipe J. Llanes-Estrada , J. Timothy Londergan , Adam P. Szczepaniak

We consider Semi-Exclusive Deeply Virtual Compton Scattering, gamma* p \to gamma Y (SECS), where Y is an inclusive state of intermediate mass, \Lambda_QCD << m_Y << Q. When the photon is produced with a large transverse momentum k_T \sim…

High Energy Physics - Phenomenology · Physics 2008-11-26 Paul Hoyer , Heidi Virtanen

We present a complete, next-to-leading-order (NLO), leading-twist QCD analysis of deeply virtual Compton scattering (DVCS) observables, in the ${\bar {MS}}$ scheme, and in the kinematic ranges of the H1, ZEUS and HERMES experiments. We use…

High Energy Physics - Phenomenology · Physics 2009-11-07 A. Freund , M. F. McDermott

Measurements of the deep-inelastic scattering (DIS) of leptons and nucleons, $e+p\to e+X$, allow the extraction of Parton Distribution Functions (PDFs) which describe the longitudinal momentum carried by the quarks, anti-quarks and gluons…

High Energy Physics - Phenomenology · Physics 2014-11-20 Laurent Schoeffel

We present in detail a dispersion relation formalism for virtual Compton scattering (VCS) off the proton from threshold into the $\Delta(1232)$-resonance region. Such a formalism can be used as a tool to extract the generalized…

High Energy Physics - Phenomenology · Physics 2016-09-06 B. Pasquini , M. Gorchtein , D. Drechsel , A. Metz , M. Vanderhaeghen

Timelike Compton scattering (TCS) i.e. the exclusive photoproduction of a lepton pair with large invariant mass nicely complements the already successful experimental study of deeply virtual Compton scattering (DVCS). The same Generalized…

High Energy Physics - Phenomenology · Physics 2012-07-12 B. Pire , L. Szymanowski , J. Wagner

We calculate $(\sqrt{-t}/Q)^k $ and $(m/Q)^k$ power corrections with $k\le 4$, where $m$ is the target mass and $t$ is the momentum transfer, to several key observables in Deeply Virtual Compton Scattering (DVCS). We find that the power…

High Energy Physics - Phenomenology · Physics 2025-01-15 V. M. Braun , Yao Ji , A. N. Manashov

The Deeply Virtual Compton Scattering (DVCS) $\gamma^* p \to \gamma p$ cross section has been measured with the H1 detector at HERA with an increased precision and in an extended kinematic domain: at photon virtualities $4<Q^2<80$ GeV$^2$,…

High Energy Physics - Experiment · Physics 2007-05-23 L. Favart

We extract the individual contributions from u and d quarks to the Dirac and Pauli form factors of the proton, after a critical examination of the available measurements of electromagnetic nucleon form factors. From this data we determine…

High Energy Physics - Phenomenology · Physics 2025-01-08 Markus Diehl , Peter Kroll

The impact of potential future measurements of beam charge asymmetries on the current knowledge of Compton form factors is evaluated. Elaborating on the results of a global neural network fit to deeply virtual Compton scattering data, a…

High Energy Physics - Phenomenology · Physics 2021-09-01 H. Dutrieux , V. Bertone , H. Moutarde , P. Sznajder

We revisit the phenomenology of the deep exclusive electroproduction of a lepton pair, i.e. double deeply virtual Compton scattering (DDVCS), in view of new experiments planned in the near future. The importance of DDVCS in the…

High Energy Physics - Phenomenology · Physics 2023-06-14 K. Deja , V. Martinez-Fernandez , B. Pire , P. Sznajder , J. Wagner

We present the first unquenched lattice-QCD calculation of the form factors for the decay $B\rightarrow D^\ast\ell\nu$ at nonzero recoil. Our analysis includes 15 MILC ensembles with $N_f=2+1$ flavors of asqtad sea quarks, with a strange…

The comparative analysis of different sets of the parton distribution functions (PDFs), based on the description of the whole sets of experimental data of electromagnetic form factors of the proton and neutron, is made in the framework of…

High Energy Physics - Phenomenology · Physics 2015-06-19 O. V. Selyugin

We present results for the nucleon electromagnetic form factors using an ensemble of maximally twisted mass clover-improved fermions with pion mass of about 130 MeV. We use multiple sink-source separations and three analysis methods to…

Having in mind the well-known limitations of certain models of generalized parton distributions (GPDs), we show that the allegedly universal GPDs, describing both deeply virtual Compton scattering (DVCS) and deeply virtual meson production…

High Energy Physics - Phenomenology · Physics 2016-04-20 Krešimir Kumerički , Dieter Müller

We discuss applications of the dispersion quark model to exclusive semileptonic decays of heavy mesons. The transition form factors in this relativistic formulation of the quark model are given by double spectral representations through the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Dmitri Melikhov

A review is given of the very recent developments in the fields of real and virtual Compton scattering off the nucleon. Both real and virtual Compton scattering reactions are discussed at low outgoing photon energy where one accesses…

High Energy Physics - Phenomenology · Physics 2016-09-06 Marc Vanderhaeghen

We present results on the quark unpolarized, helicity and transversity parton distributions functions of the nucleon. We use the quasi-parton distribution approach within the lattice QCD framework and perform the computation using an…

High Energy Physics - Lattice · Physics 2021-09-22 Constantia Alexandrou , Martha Constantinou , Kyriakos Hadjiyiannakou , Karl Jansen , Floriano Manigrasso

We compute the deeply virtual Compton scattering (DVCS) amplitude for forward and backward scattering in the asymptotic limit. We make use of the Regge calculus to resum important logarithmic contributions that are beyond those included by…

High Energy Physics - Phenomenology · Physics 2014-11-17 B. I. Ermolaev , F. Olness , A. G. Shuvaev

We extend the analysis of the deeply virtual Compton scattering process to the weak interaction sector in the generalized Bjorken limit. The virtual Compton scattering amplitudes for the weak neutral and charged currents are calculated at…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Psaker , W. Melnitchouk , A. V. Radyushkin