Soft photon production from proton-antiproton collisions at [radical]s = 1. 8 TeV

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1992

OSTI ID:7072922

Loomis, Jr, C A

Characteristics of photon production from proton-antiproton collisions at [radical]s = 1.8 TeV were measured with a NaI calorimeter. The calorimeter covered a solid angle of 75 msr and was positioned 90[degrees] from the beamline. In particular, the differential inclusive photon cross-section was measured over the transverse momentum range 30 [le] p[sub t] [le] 5000MeV/c. The goals were to search for evidence of a phase transition from normal hadronic matter to a deconfined quark-gluon plasma and for evidence of the anomalous source of soft photons that other experiments have seen. The differential inclusive photon cross-section was compared to several production models. The complexity of the production models varied from the simple Charged Pion Decay model to the complete HIJING model. The Charged Pion Decay model simulated the decay of neutral pions based on the measured transverse momentum spectrum of the charged pions. The HIJING model, on the other hand, simulated QCD processes, hadronic decays, and initial and final state radiation. This model also included minijet production. Predictions from all of the models fit the shape of the differential inclusive photon cross-section well. This agreement indicated that the cross-section was dominated by photons from decays of hadrons (primarily neutral pions). Because of the agreement between the differential cross-section and the predictions of the production models, a quark-gluon plasma contribution in proton-antiproton collisions at [radical]s = 1.8 TeV was not necessary. Comparing the differential inclusive photon cross-section to the differential cross-section predicted by several production models (normalized over all p[sub t]), it is found that any anomalous source of photons contributes [minus]3 [+-] 14% of the total in the transverse momentum range 30 [le] p[sub t] [le] 100 MeV/c.

• Research Organization: Duke Univ., Durham, NC (United States)
• OSTI ID: 7072922
• Country of Publication: United States
• Language: English

Related Subjects

662340* -- Hadron Interactions-- (1992-)
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
BARYON-BARYON INTERACTIONS
BASIC INTERACTIONS
BOSONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELECTROMAGNETIC INTERACTIONS
ELEMENTARY PARTICLES
ENERGY RANGE
HADRON-HADRON INTERACTIONS
INTERACTIONS
MASSLESS PARTICLES
MATTER
NUCLEON-ANTINUCLEON INTERACTIONS
PARTICLE INTERACTIONS
PARTICLE PRODUCTION
PHASE TRANSFORMATIONS
PHOTONS
PHOTOPRODUCTION
PROTON-ANTIPROTON INTERACTIONS
QUARK MATTER
TEV RANGE
TEV RANGE 01-10