Determination of the angular and energy dependence of hard constituent scattering from. pi. /sup 0/ pair events at the CERN intersecting storage rings

Technical Report · Mon Aug 23 04:00:00 EDT 1982

DOI:https://doi.org/10.2172/7062098· OSTI ID:7062098

Angelis, A. L.S.; Besch, H. J.; Blumenfeld, B. J.

We present data on proton-proton collisions, obtained at the CERN Intersecting Storage Rings, in which two roughly back-to-back ..pi../sup 0/'s of high transverse momentum (p/sub T/) were produced. The angular distribution of the dipion axis relative to the collision axis is found to be independent of both the effective mass m of the dipion system and the centre-of-mass energy ..sqrt..s of the proton-proton collision. The cross-sections dsigma/dm at the two values of ..sqrt..s satisfy a scaling law of the form dsigma/dm = G(x)/m/sup n/, where x = m(..pi../sup 0/,..pi../sup 0/)/..sqrt..s and n = 6.5 +- 0.5. We show from our data that the leading ..pi../sup 0/ carries most of the momentum of the scattered parton. Given this fact, the axis of the dipion system follows closely the direction of the scattered constituents, and we exploit this to determine the angular dependence of the hard-scattering subprocess. We also compare our data with the lowest order QCD predictions using structure functions as determined in deep-inelastic scattering and fragmentation functions from electron-positron annihilation.

• Research Organization: Rockefeller Univ., New York (USA); Oxford Univ. (UK); Columbia Univ., New York (USA); European Organization for Nuclear Research, Geneva (Switzerland)
• DOE Contract Number: AC02-81ER40033
• OSTI ID: 7062098
• Report Number(s): DOE/ER/40033-32; CERN-EP-82-133; CONF-820718-17; ON: DE83002451
• Country of Publication: United States
• Language: English

Related Subjects

645103* -- High Energy Physics-- Particle Interactions & Properties-Experimental-- Strong Interactions & Baryon & Meson Properties
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ANGULAR DISTRIBUTION
BARYON-BARYON INTERACTIONS
BOSONS
CERN ISR
CROSS SECTIONS
DATA
DISTRIBUTION
ELEMENTARY PARTICLES
EXPERIMENTAL DATA
FIELD THEORIES
HADRON-HADRON INTERACTIONS
HADRONS
HARD COLLISION MODELS
INCLUSIVE INTERACTIONS
INFORMATION
INTERACTIONS
LINEAR MOMENTUM
MATHEMATICAL MODELS
MESONS
MONTE CARLO METHOD
NUCLEON-NUCLEON INTERACTIONS
NUMERICAL DATA
PAIR PRODUCTION
PARTICLE INTERACTIONS
PARTICLE MODELS
PARTICLE PRODUCTION
PARTONS
PIONS
PIONS NEUTRAL
POSTULATED PARTICLES
PROTON-NUCLEON INTERACTIONS
PROTON-PROTON INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKS
STORAGE RINGS
TRANSVERSE MOMENTUM