Light-cone quantization and QCD phenomenology

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:184293

Brodsky, S J ^[1]; Robertson, D G ^[2]

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1. Stanford Univ., CA (United States). Stanford Linear Accelerator Center
2. Ohio State Univ., Columbus, OH (United States). Dept. of Physics

In principle, quantum chromodynamics provides a fundamental description of hadronic and nuclear structure and dynamics in terms of their elementary quark and gluon degrees of freedom. In practice, the direct application of QCD to reactions involving the structure of hadrons is extremely complex because of the interplay of nonperturbative effects such as color confinement and multi-quark coherence. A crucial tool in analyzing such phenomena is the use of relativistic light-cone quantum mechanics and Fock state methods to provide tractable and consistent treatments of relativistic many-body systems. In this article we present an overview of this formalism applied to QCD, focusing in particular on applications to the final states in deep inelastic lepton scattering that will be relevant for the proposed European Laboratory for Electrons (ELFE), HERMES, HERA, SLAC, and CEBAF. We begin with a brief introduction to light-cone field theory, stressing how it many allow the derivation of a constituent picture, analogous to the constituent quark model, from QCD. We then discuss several applications of the light-cone Fock state formalism to QCD phenomenology. The Fock state representation includes all quantum fluctuations of the hadron wavefunction, including far off-shell configurations such as intrinsic charm and, in the case of nuclei, hidden color. In some applications, such as exclusive processes at large momentum transfer, one can make first-principle predictions using factorization theorems which separate the hard perturbative dynamics from the nonpertubative physics associated with hadron binding. The Fock state components of the hadron with small transverse size, which dominate hard exclusive reactions, have small color dipole moments and thus diminished hadronic interactions. Thus QCD predicts minimal absorptive corrections, i.e., color transparency for quasi-elastic exclusive reactions in nuclear targets at large momentum transfer.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States); National Science Foundation, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 184293
• Report Number(s): SLAC-PUB--95-7056; CONF-9507212--1; ON: DE96004692; IN: OSU-NT--95-06; CNN: Grant PHY-9203145; Grant PHY-9258270; Grant PHY-9207889
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DEEP INELASTIC SCATTERING
LIGHT CONE
QUANTIZATION
QUANTUM CHROMODYNAMICS
QUARK MODEL
QUARKONIUM
WAVE FUNCTIONS