Timelike Virtual Compton Scattering from Electron-Positron Radiative Annihilation

Journal Article · Tue Mar 31 00:00:00 EDT 2009 · Physical Review D

OSTI ID:953021

Afanasev, Andrei; Brodsky, Stanley J; Carlson, Carl E; Mukherjee, Asmita

We propose measurements of the deeply virtual Compton amplitude (DVCS) {gamma}* {yields} H{bar H}{gamma} in the timelike t = (p{sub H} + p{sub {bar H}}){sup 2} > 0 kinematic domain which is accessible at electron-positron colliders via the radiative annihilation process e{sup +}e{sup -} {yields} H{bar H}{gamma}. These processes allow the measurement of timelike deeply virtual Compton scattering for a variety of H{bar H} hadron pairs such as {pi}{sup +}{pi}{sup -}, K{sup +}K{sup -}, and D{bar D} as well as p{bar p}. As in the conventional spacelike DVCS, there are interfering coherent amplitudes contributing to the timelike processes involving C = - form factors. The interference between the amplitudes measures the phase of the C = + timelike DVCS amplitude relative to the phase of the timelike form factors and can be isolated by considering the forward-backward e{sup +} {leftrightarrow} e{sup -} asymmetry. The J = 0 fixed pole contribution which arises from the local coupling of the two photons to the quark current plays a special role. As an example we present a simple model.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 953021
• Report Number(s): SLAC-PUB-13513; arXiv:0903.4188
• Journal Information: Physical Review D, Journal Name: Physical Review D
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AMPLITUDES
ANNIHILATION
ASYMMETRY
COMPTON EFFECT
FORM FACTORS
HADRONS
Phenomenology-HEP
HEPPH
HEPTH
PHOTONS
QUARKS