English
Related papers

Related papers: Two-Pion Exchange in proton-proton Scattering

200 papers

The contribution of the box and crossed two-pion-exchange diagrams to proton-proton scattering at 90$^{\circ}_{c.m.}$ is calculated in the laboratory momentum range up to 12 GeV/c. Relativistic form factors related to the nucleon and pion…

Nuclear Theory · Physics 2008-11-26 W. R. Gibbs , B. Loiseau

The elastic backward proton-deuteron scattering is analyzed within a covariant approach based on the Bethe-Salpeter equation with realistic meson-exchange interaction. Contributions of the one-nucleon and one-pion exchange mechanisms to the…

Nuclear Theory · Physics 2009-09-25 L. P. Kaptari , B. Kaempfer , S. M. Dorkin , S. S. Semikh

We calculate two-photon exchange amplitude for the elastic electron-pion scattering in the dispersion-relation inspired approach, including both elastic and inelastic contributions. The latter was modelled as a sum of \rho and b_1(1235)…

High Energy Physics - Phenomenology · Physics 2015-03-17 Dmitry Borisyuk , Alexander Kobushkin

We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer $Q^2$. It is shown that the leading two-photon exchange amplitude behaves as $1/Q^4$ relative to the one-photon amplitude, and…

High Energy Physics - Phenomenology · Physics 2009-09-02 Nikolai Kivel , Marc Vanderhaeghen

It has been suggested that two-photon exchange corrections could explain the discrepancy between Rosenbluth extractions of the proton form factors and recent polarization transfer measurements. We propose a precise comparison of…

From recent charge exchange measurements in the extreme forward direction, an independent and precise determination of the pion nucleon coupling constant is possible. This determination has reopened the debate on the value of this…

High Energy Physics - Phenomenology · Physics 2012-07-19 F. Myhrer

We perform detailed calculations of two-photon-exchange QED corrections to the cross section of pion electroproduction. The results are obtained with and without the soft-photon approximation; analytic expressions for the radiative…

Nuclear Theory · Physics 2013-09-25 A. Afanasev , A. Aleksejevs , S. Barkanova

We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer through the scattering off a parton in the proton. We relate the process on the nucleon to the generalized parton…

High Energy Physics - Phenomenology · Physics 2009-09-11 Y. C. Chen , A. Afanasev , S. J. Brodsky , C. E. Carlson , M. Vanderhaeghen

We study two-photon exchange for elastic electron-proton scattering at low Q^2. Compact approximate formulae for the amplitudes are obtained. Numerical calculations are done for Q^2 < 0.1 GeV^2 with several realistic form factor…

Nuclear Theory · Physics 2008-11-26 Dmitry Borisyuk , Alexander Kobushkin

We extend the general formalism of two-photon exchange to elastic lepton-nucleon scattering by accounting for all lepton mass terms. We then perform a numerical estimate of the muon-proton scattering at low momentum transfer in view of the…

High Energy Physics - Phenomenology · Physics 2014-07-16 O. Tomalak , M. Vanderhaeghen

We present the dispersion relation approach based on unitarity and analyticity to evaluate the two-photon exchange contribution to elastic electron-proton scattering. The leading elastic and first inelastic $\pi N$ intermediate state…

High Energy Physics - Phenomenology · Physics 2018-07-04 Oleksandr Tomalak

Recent theoretical developments in the studies of two-photon exchange effects in elastic electron-proton scattering are reviewed. Two-photon exchange mechanism is considered a likely source of discrepancy between polarized and unpolarized…

High Energy Physics - Phenomenology · Physics 2017-08-23 Andrei V. Afanasev

Two-photon exchange contributions to elastic electron-proton scattering cross sections are evaluated in a simple hadronic model including the finite size of the proton. The corrections are found to be small in magnitude, but with a strong…

Nuclear Theory · Physics 2008-11-26 P. G. Blunden , W. Melnitchouk , J. A. Tjon

The process of two pion production in the electron-polarized proton scattering is investigated. In the Weizs\"acker-Williams approximation the differential spectral distributions and the spin-momentum correlations are considered. The spin…

High Energy Physics - Phenomenology · Physics 2013-04-02 A. I. Ahmadov , E. A. Kuraev , Yu. M. Bystritskiy

We examine the two-photon exchange corrections to elastic electron-proton scattering within a dispersive approach, including contributions from both Nucleon and Delta intermediate states. The dispersive analysis avoids off-shell…

Nuclear Theory · Physics 2017-06-21 P. G. Blunden , W. Melnitchouk

We review the role of two-photon exchange (TPE) in electron-hadron scattering, focusing in particular on hadronic frameworks suitable for describing the low and moderate Q^2 region relevant to most experimental studies. We discuss the…

Nuclear Theory · Physics 2015-05-28 J. Arrington , P. G. Blunden , W. Melnitchouk

A microscopic model for the $N\bar N\to\pi\pi$ process is presented in the meson exchange framework, which in the pseudophysical region agrees with available quasiempirical information. The scalar ($\sigma$) and vector ($\rho$) piece of…

Nuclear Theory · Physics 2009-09-25 C. Schütz , J. W. Durso , K. Holinde , B. C. Pearce , J. Speth

Parity nonconserving two-pion exchange in elastic pp scattering is investigated in the presence of phenomenological strong distortions in various models. Parity violation is included in the nucleon-pion vertex considering NN and N…

Nuclear Theory · Physics 2008-11-26 J. A. Niskanen , T. M. Partanen , M. J. Iqbal

We calculate the effects on the elastic electron-proton scattering cross section of the two-photon exchange contribution with an intermediate $\Delta$ resonance. The $\Delta$ two-photon exchange contribution is found to be smaller in…

Nuclear Theory · Physics 2014-11-18 S. Kondratyuk , P. G. Blunden , W. Melnitchouk , J. A. Tjon

Higher-order QED effects play an important role in precision measurements of nucleon elastic form factors in electron scattering. Here we introduce a two-photon exchange QED correction to the parity-violating polarization asymmetry of…

High Energy Physics - Phenomenology · Physics 2008-11-26 Andrei V. Afanasev , Carl E. Carlson
‹ Prev 1 2 3 10 Next ›