Energy loss of fast quarks in nuclei

Conference · Mon Jan 01 04:00:00 EST 2001

OSTI ID:975727

Garvey, G T ^[1]; Johnson, Mikkel B; Leitch, M J; McGaughey, P L ^[2]; Peng, J C ^[3]; Kopeliovich, B Z; Potashnikova, I K; Moss, J M ^[4]

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1. Gerald T.
2. Patrick L.
3. Jen-Chieh
4. Joel Marshall

We report an analysis of the nuclear dependence of the yield of Drell-Yan (DY) dimuons from the 800 GeV/c proton bombardment of {sup 2}H, C, Ca, Fe, and W targets. A light-cone formulation of the DY process is employed in the rest frame of the nucleus. In this frame, for x{sub 2} <<x{sub 1}, DY production appears as bremsstrahlung of a virtual photon followed by decay into dileptons. We treat the two sources of nuclear suppression, energy loss and shadowing, in a consistent formulation. Shadowing, involving no free parameters, is calculated within the light-cone dipole formalism. Initial-state energy loss, the only unknown in the problem, is determined from afit to the nuclear-dependence ratio versus x{sub 1}. With the assumption of constant energy loss per unit path length, we find -dE/dz = 2.32 {+-} 0.52 {+-} 0.5 GeV/fm. This is the first observation of a nonzero energy loss of partons traveling in nuclear environment.

• Research Organization: Los Alamos National Laboratory
• Sponsoring Organization: DOE
• OSTI ID: 975727
• Report Number(s): LA-UR-01-4960
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
BREMSSTRAHLUNG
DECAY
DIPOLES
LIGHT CONE
NUCLEAR PHYSICS
NUCLEI
PHOTONS
PRODUCTION
PROTONS
QUARKS
TARGETS