The most basic forms of matter exist in solid, liquid or gaseous states while plasmas and nuclear matter are related variations. Nuclear and particle theorists now speculate that it may be possible to produce, in the laboratory, quark matter or a quark-gluon plasma similar to matter of the very early Universe. Our work in experimental nuclear physics focuses on attempts to produce and to study such matter. We do this by studying collisions between (heavy) nuclei over a wide range of relativistic energies, up to the highest available, where quark deconfinement and plasma formation may take place. These collisions illustrate properties of bulk nuclear matter over a range of conditions of density, temperature, etc.
At lower (GeV per nucleon) energies, the densities increase four or five times that of the normal nuclear matter (nuclei in their ground - unexcited states), and temperatures increase to 100 to 150 MeV when heavy nuclei collide. We are trying to determine the equation of state under these conditions and the related liquid-gas-type phase transitions. These studies have been carried out at the Bevalac at Lawrence Berkeley Laboratory and at the Alternating Gradient Synchrotron (AGS) accelerator at Brookhaven Laboratories [BNL] on Long Island, New York. At the higher energies used at the European Organization for Nuclear Research (CERN) (17 GeV per nucleon CM for heavy gold beams) the experimental data produced strong hints that conditions for quark matter formation were achieved. Presently, at the Relativistic Heavy Ion Collider [ RHIC] at BNL is being used to study the energy range from that at CERN up to much higher energies [200 GeV CM for colliding Gold nuclei] to try to verify the production of and to study quark matter, and its behavior over this extended energy range.
Neutron scattering data taken at LANL is being analysed . It covers the widest range and largest energies measured for elastic neutron scattering.
Honors and Awards
F. Paul Brady
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