Creation of strongly coupled plasmas using intense beams of 400 MeV/u uranium ions to be generated at the Gesellschaft fur Schwerionenforschung (GSI)Darmstadt SIS-200

The heavy ion synchrotron, SIS-18 (that has an 18 Tm magnetic rigidity), at the Gesellschaft fur Schwerionenforschung (GSI), Darmstadt is a unique fac ility worldwide that delivers intense beams of energetic heavy ions. The GS I has plans to extend its accelerator capabilities by building a new synchr otron (SIS-200) with a much higher magnetic rigidity of 200 Tm. According t o the preliminary design considerations, the SIS-200 will generate a uraniu m beam that will consist of at least 10(12) particles and that will be deli vered in a 50 ns long pulse. This beam will be used to study various intere sting problems, including fragmentation of the projectile ions while passin g through solid matter and creation of high-density, strongly coupled plasm as. For the former type of studies, a particle energy of 1 GeV/u has been c onsidered to be appropriate, while for the latter case, a lower value of 40 0 MeV/u has been found to be most suitable. In this paper we present, with the help of two-dimensional numerical simulations, the hydrodynamic and the rmodynamic response of a solid lead cylindrical target that is irradiated w ith the future SIS-200 beam, which has a particle energy of 400 MeV/u. The beam focal spot is assumed to be circular and the power deposition profile is considered to be Gaussian along the radial direction. Calculations have also been done using a beam that has a ring-shaped (annular) focal spot tha t interacts with solid as well as hollow lead cylinders, respectively. In a ll the above cases it has been assumed that the cylinder length is shorter than the range of 400 MeV/u uranium ions in solid lead so that the Bragg pe ak does not lie inside the target and the energy deposition is almost unifo rm along the particle trajectory. These simulations show that it will be po ssible to create extended volumes of high-density, strongly coupled plasmas using the future SIS-200 beam. (C) 2000 American Institute of Physics. [S1 070- 664X(00)01811-5].