We have measured the production cross-section times branching ratio for J/PSI --> mu+ mu- in ppBAR interactions at square-root s = 630 GeV in the kinematic range /y/ < 2.0 and p(T) > 5 GeV/c, BR (J/PSI --> mu+ mu-)sigma(ppBAR --> J/PSI) = 6.18 +/- 0.24 +/- 0.81 nb. The data sample collected in 1988 and 1989 for an integrated luminosity of 4.7 pb-1 represents a fivefold improvement over the statistics in our earlier study of the J/PSI production process, and the P(T) distribution which is measured extends to 28 GeV/c. Using event topology we show that the rate for the direct production of J/PSI, via radiative decays of chi-states, is larger than that for production via B-hadrons. Production of PSI' is also studied using the decay modes PSI' --> mu+ mu- and PSI' --> J/PSI-pi+pi-.
J/PSI AND PSI' PRODUCTION AT THE CERN P-BARP COLLIDER
CAVANNA, FLAVIO;
1991-01-01
Abstract
We have measured the production cross-section times branching ratio for J/PSI --> mu+ mu- in ppBAR interactions at square-root s = 630 GeV in the kinematic range /y/ < 2.0 and p(T) > 5 GeV/c, BR (J/PSI --> mu+ mu-)sigma(ppBAR --> J/PSI) = 6.18 +/- 0.24 +/- 0.81 nb. The data sample collected in 1988 and 1989 for an integrated luminosity of 4.7 pb-1 represents a fivefold improvement over the statistics in our earlier study of the J/PSI production process, and the P(T) distribution which is measured extends to 28 GeV/c. Using event topology we show that the rate for the direct production of J/PSI, via radiative decays of chi-states, is larger than that for production via B-hadrons. Production of PSI' is also studied using the decay modes PSI' --> mu+ mu- and PSI' --> J/PSI-pi+pi-.Pubblicazioni consigliate
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