文档介绍：Surprises from RHIC
John G. Cramer
Department of Physics University of Washington
Colloquium
UW Physics Department
March 4, 2002
Part 1
About RHIC
(The Relativistic Heavy Ion Collider)
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Brookhaven/RHIC Overview
Systems:
Au + Au
CM Energies:
130 GeV/A
200 GeV/A 1st Collisions:
06/13/2000 Location:
Brookhaven National Laboratory,
Long Island, NY
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Booster
Ring
AGS
Switchyard
RHIC
Tandem Van de Graaff
The RHIC Accelerator System
Blue Ring
Yellow Ring
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What does RHIC do?
RHIC accelerates gold nuclei in two
beams to about 100 Gev/nucleon each
(., to ic energies that are over
100 times their rest mass-energy)
and brings these beams into a
200 GeV/nucleon collision.
Four experiments, STAR,
PHENIX, PHOBOS, and
BRAHMS study these collisions.
In the year 2000 run, RHIC
operated at a collision energy
of 130 Gev/nucleon.
In 2001-2 it operated at 200 GeV/nucleon.
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About the STAR Detector.
ZCl
Barrel EM Calorimeter
Endcap Calorimeter
Coils
TPC Endcap & MWPC
ZCal
FTPCs
Vertex Position Detectors
Central Trigger Barrel or TOF
Time Projection Chamber
Silicon Vertex Tracker
RICH
STAR is a large solenoidal detector based on a time- projection chamber. It uses a tesla ic field to momentum-analyze about 2,000 charged particles per collision.
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The STAR Collaboration
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Run: 1186017, Event: 32, central
colors ~ momentum: low - - - high
Central Au +Au Collision at sNN = 130 GeV
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Part 2
RHIC Surprises
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In Search of the Quark-Gluon Plasma (QGP)
A QGP should have more degrees of freedom than a pion gas.
Entropy should be conserved during the fireball’s evolution.
Hence, look in phase space for evidence of:
Large size,
Long lifetime,
Extended expansion……
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