Author: Robert Clarence PerishoPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
An Upper Bound on the Two Photon-Exchange Amplitude for Electron-Proton Elastic Scattering
Two Photon Exchange in Electron-proton Scattering
Author: Gary Kalman GreenhutPublisher:
ISBN:
Category : Electrons
Languages : en
Pages : 324
Book Description
The Two-photon Exchange Contribution to Elastic Electron-nucleon Scattering at Large Momentum Transfer
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We estimate the two-photon exchange contribution to elastic electron-proton scattering at large momentum transfer by using a quark-parton representation of virtual Compton scattering. We thus can relate the two-photon exchange amplitude to the generalized parton distributions which also enter in other wide angle scattering processes. We find that the interference of one- and two-photon exchange contribution is able to substantially resolve the difference between electric form factor measurements from Rosenbluth and polarization transfer experiments.
TWO-PHOTON EXCHANGE IN ELECTRON-PROTON ELASTIC SCATTERING
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
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 experimental measurements of the proton electric form factor at momentum transfers of several GeV$^2$. This mechanism predicts measurable effects that are currently studied experimentally.
The Contribution of Two-photon Exchange in Elastic Lepton-proton Scattering
Author: Colton David Graham O'ConnorPublisher:
ISBN:
Category :
Languages : en
Pages : 307
Book Description
Measurements of the electric-to-magnetic ratio of the proton's elastic form factors, GE/GM, have recently been shown to diverge at high momentum transfer, Q2, based on which of two experimental methods is employed. Reanalysis of all results might be able to bring them into agreement if some previously neglected correction were introduced whose magnitude increases with Q2. In the high-energy community, two-photon exchange has become the favored candidate for such a correction. But theoretical models disagree on the size and form of a two-photon exchange correction term entering into elastic lepton-proton scattering and existent empirical data is not sufficiently precise to settle the matter. OLYMPUS is one of several new experiments designed to evaluate R2[gamma], the ratio of the elastic cross sections for positron-proton and electron-proton scattering, whose difference from unity provides a direct measure of the amplitude of the two-photon exchange matrix elements. In this dissertation, OLYMPUS is considered from its motivation, construction, and operation to its analysis, along with the associated Monte Carlo simulation. Special attention is given to the symmetric Møller/Bhabha detector system, which is not described in full elsewhere. The results achieved by the OLYMPUS collaboration, reported herein, achieve unprecedented precision over a wide kinematic range and make a significant contribution to the understanding of two-photon exchange.
Two-photon Exchange and Elastic Electron-proton Scattering
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
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, but with a strong angular dependence at fixed Q2. This is significant for the Rosenbluth technique for determining the ratio of electric and magnetic form factors of the proton, and partly reconciles the apparent discrepancy with the results of the polarization transfer technique.
Two Photon Exchange Radiative Correction to Electron-proton Elastic Scattering
Author: Jaseer AhmedTwo-Photon Exchange Effects in Elastic Electron-Proton Scattering
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 89
Book Description
Two methods, Rosenbluth separation and polarization transfer, can be used to extract the proton form factor ratio [mu]p GEp/GMp, but they do not yield the same results. It is thought that the disagreement is due to two photon exchange corrections to the differential cross sections. High precision proton Rosenbluth extractions were carried out at 102 kinematics points spanning 16 values of momentum transfer Q2, from 0.40 to 5.76 GeV2. Reduced cross sections were found to 1.1% or better for Q2 less than 3 GeV2 increasing to 4% at 5.76 GeV2 The form factor ratios were determined to 1:5-3% for Q2
Elastic and Inelastic Electron-proton Scattering
Author: Ernest Albert AlltonPublisher:
ISBN:
Category :
Languages : en
Pages : 306
Book Description
Two-photon Exchange in Elastic and Inelastic Electron-proton Scattering
Author: W. MelnitchoukPublisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We present an explicit quantum field theoretical calculation of two-photon exchange contribution to elastic electron-proton scattering and to Delta resonance production in electron-proton collisions.