Measuring Form Factors and Structure Functions with CLAS.

Gilfoyle, G. P.

Technical Information Center Oak Ridge Tennessee

关键词: Form factors;    Neutrons;    Structure functions;    Atomic nuclei;    Quantum chromodynamics;   

RP-ID  :  DE2007920580

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

The physics program at the Thomas Jefferson National Accelerator Facility includes a strong effort to measure form factors and structure functions to probe the structure of hadronic matter, reveal the nature of confinement, and develop an understanding of atomic nuclei using quark-gluon degrees of freedom. The CLAS detector is a large acceptance device occupying one of the end stations. We discuss here two programs that use CLAS; measuring the magnetic form factor of the neutron, and the virtual photon asymmetry of the proton. The form factor has been measured with unprecedented kinematic coverage and precision up to Q2 = 4.7 GeV2 and is consistent within 5%- 10% of the dipole parameterization. The proton virtual photon asymmetry has been measured across a wide range in Bjorken x. The data exceed the SU(6)-symmetric quark prediction and show evidence of a smooth approach to the scaling limit prescribed by perturbative QCD.