Direct photon production in pp and anti p p collisions

Conference · Thu Jan 01 04:00:00 EST 1987

OSTI ID:5061178

Cox, P T

The simplicity of the leading-order production processes for direct (single) gamma production in pp and /bar p/p collisions, i.e. the QCD-Compton process qg ..-->.. ..gamma..q and the annihilation process qq ..gamma..g, is appealing, since the photon carries all the p/sub T/ of the parton collision, and there is no confusion from fragmentation. Furthermore the ratio R = sigma(/bar p/p ..--> gamma..X)sigma(pp ..--> gamma.. X) should be sensitive to the hardness of the gluon structure fucntion of the nucleon. Since qq annihilation is clearly more important in /bar p/p than pp, due to the valence q quarks, R is expected to be larger than one, and since the gluon structure function is known to be relatively soft so that /bar q/q should become increasingly favoured over qg as p/sub T/ of the emitted gamma ray. Experiment UA6 at CERN is a fixed-target experiment using a hydrogen gas jet target in the SPS Collider /bar p/(or p) beam to study high p /sub T/ ..pi.. /degree/, /eta/, and ..gamma.. production in /bar p/p and pp collisions at ..sqrt.. s = 24.3 GeV (when the Collider beam momenta are 315 GeVc). Electron pairs, including J/psi/ ..-->.. e/sup +/e/sup /minus//, can be studied. The collaborating institutes are CERN, the University of Lausanne, the University of Michigan, and The Rockefeller University.

• Research Organization: Rockefeller Univ., New York (USA)
• DOE Contract Number: AC02-87ER40325
• OSTI ID: 5061178
• Report Number(s): DOE/ER/40325-9A; CONF-8710276-3; ON: DE88008769
• Country of Publication: United States
• Language: English

Related Subjects

645101* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Electromagnetic Interactions & Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYON-BARYON INTERACTIONS
BOSONS
CROSS SECTIONS
DATA
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FIELD THEORIES
HADRON-HADRON INTERACTIONS
HADRONS
INFORMATION
INTERACTIONS
MAGNETIC SPECTROMETERS
MASS SPECTRA
MASSLESS PARTICLES
MEASURING INSTRUMENTS
MESONS
NUCLEON-ANTINUCLEON INTERACTIONS
NUCLEON-NUCLEON INTERACTIONS
NUMERICAL DATA
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PHOTONS
PIONS
PIONS NEUTRAL
PROTON-ANTIPROTON INTERACTIONS
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
SPECTRA
SPECTROMETERS