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Elliptic flow in Au+Au collisions at square root(S)NN = 130 GeV
K H Ackermann1, N Adams, C Adler
1Argone National Laboratory, Illinois 60439, USA.
Physical Review Letters
|February 15, 2001
Summary
We measured elliptic flow (v2) in gold-gold collisions at 130 GeV. Results show a higher degree of thermalization, with v2 decreasing in more central collisions.
Area of Science:
- Nuclear Physics
- High-Energy Physics
- Particle Physics
Background:
- Elliptic flow (v2) is a key hadronic observable in nuclear collisions.
- It provides insights into the early stages of system evolution and thermalization.
Purpose of the Study:
- To report the first measurements of elliptic flow for charged particles.
- To investigate the behavior of elliptic flow in gold-gold collisions at a center-of-mass energy of 130 GeV per nucleon.
Main Methods:
- Utilized the STAR Time Projection Chamber at the Relativistic Heavy Ion Collider.
- Analyzed charged particle production at midrapidity in Au+Au collisions.
Main Results:
- The averaged elliptic flow (v2) reached approximately 6% in peripheral collisions.
- Elliptic flow decreased as collisions became more central.
- Presented the pseudorapidity and transverse momentum dependence of elliptic flow.
Conclusions:
- Observed a higher degree of thermalization compared to lower collision energies.
- The results offer crucial data for understanding the properties of matter created in heavy-ion collisions.
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