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Antideuteron yield at the AGS and coalescence implications
1Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Physical Review Letters
|September 16, 2000
Summary
Experiment 864 measured invariant antideuteron yields in gold-platinum collisions. The findings provide insights into antimatter production and annihilation processes in high-energy nuclear physics.
Area of Science:
- Nuclear Physics
- Particle Physics
- High-Energy Physics
Background:
- Understanding antimatter production is crucial for testing the Standard Model.
- Heavy-ion collisions provide a unique environment to study the formation of exotic particles like antideuterons.
Purpose of the Study:
- To measure invariant antideuteron yields in 11.5A GeV/c gold-platinum collisions.
- To investigate the production mechanisms and coalescence parameters of antideuterons.
Main Methods:
- Analysis of 250x10^6 triggers from 14x10^9 central interactions in Experiment 864.
- Measurement of differential yields (1/2πp(t))d^2N/dydp(t) and the coalescence parameter B2.
Main Results:
- Invariant antideuteron yields were determined in specific rapidity (y) and transverse momentum (p(t)) ranges.
- A coalescence parameter B2 of 4.1+/-2.9(stat)+2.3-2.4(syst)x10^-3 GeV^2c^-3 was found.
Conclusions:
- The measured yields and coalescence parameter offer insights into antideuteron formation.
- Results have implications for understanding antimatter annihilation and nuclear matter at extreme conditions.
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