The study of proton-nucleus and nucleus-nucleus
                                      collisions with the ATLAS detector.

                                                    Helio Takai
                                           Physics Department
                                        Brookhaven National Laboratory

The ATLAS detector is one of the two large detectors being built to
carry on high pT physics  at the Large Hadron Collider.  The detector
is designed to perform optimally at the challenging nominal LHC
machine luminosity of 1034 cm-2s-1. ATLAS has a finely segmented
electromagnetic and hadronic calorimeters covering 10 units of
rapidity. The inner tracking system is composed of  sicilicon pixel
detector, silicon central tracker, transition radiation tracker and a
2T solenoidal magnet, covering 5 units of rapidity. The muon
spectrometer is located outside the calorimeter volume. Muon chambers
and air core toroids are used to track muons of momentum larger than
4 GeV.  Results from RHIC on jet quenching observed in Au+Au
collisions have stimulated the ATLAS collaboration to pursue a
program centered around jet physics and upsilon suppression.  The
ATLAS detector has a superb performance for jet physics because of
its calorimeters. Preliminary simulation studies also indicate that
it will be possible to tag b-jets in the heavy ion environment.
Upsilon and J/Psi can be reconstructed through the di-muon decay
channel. The detector is ideal for the study of global variables,
namely total energy flow and particle production multiplicity.  We
will discuss in some detail the ATLAS detector and its expected
performance in the study of proton-nucleus and nucleus-nucleus
collisions.






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Ming X. Liu        Tel:(505)667-7125
P-25, MS H846            (631)924-4542(BNL)
Los Alamos, NM 87545    Fax:(505)665-79200
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