Deeply virtual Compton scattering at Jefferson Laboratory
Abstract
The generalized parton distributions (GPDs) have emerged as a universal tool to describe hadrons in terms of their elementary constituents, the quarks and the gluons. Deeply virtual Compton scattering (DVCS) on a proton or neutron ($N$), $$e N \rightarrow e' N' \gamma$$, is the process more directly interpretable in terms of GPDs. The amplitudes of DVCS and BetheHeitler, the process where a photon is emitted by either the incident or scattered electron, can be accessed via crosssection measurements or exploiting their interference which gives rise to spin asymmetries. Spin asymmetries, cross sections and crosssection differences can be connected to different combinations of the four leadingtwist GPDs ($${H}$$, $${E}$$, $${\tilde{H}}$$, $${\tilde{E}}$$) for each quark flavors, depending on the observable and on the type of target. This paper gives an overview of recent experimental results obtained for DVCS at Jefferson Laboratory in the halls A and B. Several experiments have been done extracting DVCS observables over large kinematics regions. Multiple measurements with overlapping kinematic regions allow to perform a quasimodel independent extraction of the Compton form factors, which are GPDs integrals, revealing a 3D image of the nucleon.
 Authors:
 Fairfield University  Department of Physics 1073 North Benson Road, Fairfield, CT 06430, USA; Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
 Publication Date:
 Research Org.:
 Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), Nuclear Physics (NP) (SC26)
 OSTI Identifier:
 1332086
 Report Number(s):
 JLABPHY152152; DOE/OR/231773991; arXiv:1510.04558
 DOE Contract Number:
 AC0506OR23177
 Resource Type:
 Conference
 Resource Relation:
 Conference: CIPANP 2015, Vail, CO (United States), 1924 May 2015
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Biselli, Angela S. Deeply virtual Compton scattering at Jefferson Laboratory. United States: N. p., 2016.
Web.
Biselli, Angela S. Deeply virtual Compton scattering at Jefferson Laboratory. United States.
Biselli, Angela S. 2016.
"Deeply virtual Compton scattering at Jefferson Laboratory". United States.
doi:. https://www.osti.gov/servlets/purl/1332086.
@article{osti_1332086,
title = {Deeply virtual Compton scattering at Jefferson Laboratory},
author = {Biselli, Angela S.},
abstractNote = {The generalized parton distributions (GPDs) have emerged as a universal tool to describe hadrons in terms of their elementary constituents, the quarks and the gluons. Deeply virtual Compton scattering (DVCS) on a proton or neutron ($N$), $e N \rightarrow e' N' \gamma$, is the process more directly interpretable in terms of GPDs. The amplitudes of DVCS and BetheHeitler, the process where a photon is emitted by either the incident or scattered electron, can be accessed via crosssection measurements or exploiting their interference which gives rise to spin asymmetries. Spin asymmetries, cross sections and crosssection differences can be connected to different combinations of the four leadingtwist GPDs (${H}$, ${E}$, ${\tilde{H}}$, ${\tilde{E}}$) for each quark flavors, depending on the observable and on the type of target. This paper gives an overview of recent experimental results obtained for DVCS at Jefferson Laboratory in the halls A and B. Several experiments have been done extracting DVCS observables over large kinematics regions. Multiple measurements with overlapping kinematic regions allow to perform a quasimodel independent extraction of the Compton form factors, which are GPDs integrals, revealing a 3D image of the nucleon.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 8
}

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