Measurement of kinematic and nuclear dependence of [ital R]=[sigma][sub [ital L]]/[sigma][sub [ital T]] in deep inelastic electron scattering

Journal Article · Wed Jun 01 00:00:00 EDT 1994 · Physical Review, D (Particles Fields); (United States)

DOI:https://doi.org/10.1103/PhysRevD.49.5641· OSTI ID:7308408

Dasu, S; de Barbaro, P; Bodek, A; Harada, H; Krasny, M W; Lang, K; Riordan, E M ^[1]; Andivahis, L; Arnold, R; Benton, D; Bosted, P; deChambrier, G; Lung, A; Rock, S E; Szalata, Z M ^[2]; Walker, R C; Filippone, B W; Jourdan, J; Milner, R; McKeown, R ; Potterveld, D ^[3]; Para, A ^[4]; Dietrich, F; Van Bibber, K ^[5]; Button-Shafer, J; Debebe, B; Hicks, R S ^[6]; Gearhart, R; Whitlow, L W ^[7]; Alster, J ^[8]

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1. University of Rochester, Rochester, New York 14627 (United States)
2. The American University, Washington, D.C. 20016 (United States)
3. California Institute of Technology, Pasadena, California 91125 (United States)
4. Fermi National Accelerator Laboratory, Batavia, Illinois 60510 (United States)
5. Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)
6. University of Massachusetts, Amherst, Massachusetts 01003 (United States)
7. Stanford Linear Accelerator Center, Stanford, California 94305 (United States)
8. University of Tel-Aviv, Ramat Aviv, Tel-Aviv 69978

We report results on a precision measurement of the ratio [ital R]=[sigma][sub [ital L]]/[sigma][sub [ital T]] in deep inelastic electron-nucleon scattering in the kinematic range 0.2[le][ital x][le]0.5 and 1[le][ital Q][sup 2][le]10 (GeV/[ital c])[sup 2]. Our results show, for the first time, a clear falloff of [ital R] with increasing [ital Q][sup 2]. Our [ital R] results are in agreement with QCD predictions only when corrections for target mass effects and some additional higher twist effects are included. At small [ital x], the data on [ital R] favor structure functions with a large gluon contribution. We also report results on the differences [ital R][sub [ital A]][minus][ital R][sub [ital D]] and the cross section ratio [sigma][sup [ital A]]/[sigma][sup [ital D]] between Fe and Au nuclei and the deuteron. Our results for [ital R][sub [ital A]][minus][ital R][sub [ital D]] are consistent with zero for all [ital x],[ital Q][sup 2] indicating that possible contributions to [ital R] from nuclear higher twist effects and spin-0 constituents in nuclei are not different from those in nucleons. The ratios [sigma][sup [ital A]]/[sigma][sup [ital D]] from all recent experiments, at all [ital x],[ital Q][sup 2] values, are now in agreement.

• DOE Contract Number: AC02-76ER13065; AC02-76ER02853; AC03-76SF00515; W-7405-ENG-48
• OSTI ID: 7308408
• Journal Information: Physical Review, D (Particles Fields); (United States), Vol. 49:11; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CROSS SECTIONS
EMC EFFECT
DEEP INELASTIC SCATTERING
ELECTRON-NUCLEON INTERACTIONS
DEUTERONS
GLUONS
GOLD
IRON
MASS
QUANTUM CHROMODYNAMICS
STRUCTURE FUNCTIONS
BOSONS
CHARGED PARTICLES
ELEMENTARY PARTICLES
ELEMENTS
FIELD THEORIES
FUNCTIONS
INELASTIC SCATTERING
INTERACTIONS
LEPTON-BARYON INTERACTIONS
LEPTON-HADRON INTERACTIONS
LEPTON-NUCLEON INTERACTIONS
METALS
PARTICLE INTERACTIONS
POSTULATED PARTICLES
QUANTUM FIELD THEORY
SCATTERING
TRANSITION ELEMENTS
662330* - Photon & Charged-Lepton Interactions with Hadrons- (1992)
662230 - Quantum Chromodynamics- (1992-)
663420 - Lepton-Induced Reactions & Scattering- (1992-)