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Observation of diffractive J/psi production at the Fermilab Tevatron
T Affolder1, H Akimoto, A Akopian
1Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Physical Review Letters
|December 12, 2001
Summary
This study reports the first observation of diffractive J/psi production in proton-proton collisions. The findings provide insights into the proton
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Chromodynamics
Background:
- Diffractive J/psi production is a key process for studying the proton's internal structure.
- Understanding the gluon contribution to the proton's structure function is crucial.
Purpose of the Study:
- To report the first observation of diffractive J/psi production in proton-proton collisions at 1.8 TeV.
- To determine the gluon fraction of the proton's diffractive structure function.
Main Methods:
- Identification of diffractive events using rapidity gap signature.
- Measurement of J/psi --> mu+mu- decays in pp collisions at sqrt(s) = 1.8 TeV.
- Analysis of diffractive J/psi production as a function of Bjorken-x.
Main Results:
- First observation of diffractive J/psi production in pp collisions at 1.8 TeV.
- Ratio of diffractive to total J/psi production R(J/psi) = [1.45 +/- 0.25]%.
- Extracted gluon fraction of the diffractive structure function: 0.59 +/- 0.15.
Conclusions:
- Diffractive J/psi production provides a sensitive probe of the proton's gluon content.
- The results contribute to a more complete understanding of the proton's internal dynamics and the role of gluons.
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