Evaluation of the Higher Twist Contribution to the Moments of Proton Structure Functions F2 and g1

Conference · Fri Aug 01 04:00:00 EDT 2003

OSTI ID:836845

Osipenko, Mikhail; Simula, Silvano; Ricco, Giovanni; Fedotov, Gleb; Golovatch, Evgueni; Ishkhanov, Boris; Isupov, Eugeny; Mokeev, Viktor

We performed the measurement of the inclusive electron scattering off the proton in the resonance region (W<2.5 GeV) at momentum transfer Q2 below 4.5 (GeV/c){sup 2} with the CLAS detector. The large acceptance of CLAS provided an access to a large, continuous two-dimensional kinematic domain in Q2 and x, allowing therefore an integration of the data at fixed Q2 over x-interval. The covered x-interval at each measured Q2 value is sufficient for an evaluation of the higher moments (n>2). From these data we extracted the structure function F2 and, by including other world data, we studied the Q2 evolution of its moments, Mn(Q2), in order to estimate the higher twist contributions. A similar experiment with polarized proton target is completed at CLAS. These new data allow an accurate determination of higher moments of the proton structure function g1. A preliminary phenomenological analysis indicates an excess of the higher twist contribution in the spin-dependent structure function with respect to the spin-independent one.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (US)
• Sponsoring Organization: US Department of Energy; USDOE Office of Energy Research (ER) (US)
• DOE Contract Number: AC05-84ER40150
• OSTI ID: 836845
• Report Number(s): JLAB-PHY-03-228; DOE/ER/40150-5025; hep-ph/0312288
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ELECTRONS
ELEMENTARY PARTICLES
EVALUATION
MOMENTUM TRANSFER
PHYSICS
PROTONS
RESONANCE
SCATTERING
STRUCTURE FUNCTIONS
TARGETS