Laboratory Directed Research and Development at Lawrence Livermore National Laboratory (LDRD). Final report, Project No. 95-ERD-039

摘要

One of the last frontiers in nuclear physics is the discovery of the high baryon density, high temperature transition from normal hadronic matter to the unbound quark-gluon plasma or QGP. We believe that it is possible to create the QGP in the laboratory by colliding large nuclei (typically beams of gold nuclei) at relativistic energies. We proposed to use an innovative device designed and fabricated by LLNL scientists to study collective phenomena as a function of the Au beam energy between 2 and 11 GeV/A. If the QGP is formed at these energies, it is quite possible that a measure of collective hydrodynamic flow would be a truly unambiguous signature of QGP formation. The goal of this proposal was to measure the collective flow as a function of the incident projectile (gold beam) energy between 2 and 11 GeV/A and search for anomalies in the flow excitation function which might indicate QGP formation. This was a three-year program tied directly to the anticipated running schedule of the AGS. During the initial state of this project, the LLNL projectile hodoscope was used in AGS experiment E866 to complete the measurement of collective flow in Au+Au collisions at 11 GeV/A. The next stage in the experimental program would have been to make identical flow measurements at beam energies of 2,4,6 and 8 GeV/A. Two separate running periods were scheduled in early FY96 for beams of 2 and 4 GeV/A. These measurements would have completed a full flow excitation function between the current measurement at 11 GeV/A and lower energy data (1 GeV/A) where we know the flow is considerably larger (300 MeV/c at a beam energy of 1 GeV/A). With the termination of this project after the first year, the opportunity to make these measurements has been lost.