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The hydrodynamic behavior of metal targets when heated by intense proton beams was simulated numerically. The dependence of the achieved warm dense matter state for targets with different materials was investigated by means of a computer code based on two-dimensional fluid models with quantum corrections. Under the irradiation of a proton beam with an energy of 10 MeV, a particle number of 7.9 × 107, and a pulse duration of 10 ps, the numerical simulation results show that the achieved state is significantly influenced by the Winger-Seitz radius rs of materials.

The knowledge of the net charge of conducting spheres has gained much interest in the context of high power laser interaction with clusters, dust, impurities, aerosols, and small liquid droplets. Contrary to a general supposition based on linearized plasma quasineutrality it is shown that in electronic thermal equilibrium spheres of one Debye length radius lose almost all free electrons, hence are highly charged. Quasineutrality is approximately reached for pellet sizes R exceeding 30 times the Debye length. In order to gain an estimate of the net charge of nonspherical particles the equilibrium charge is determined in slab geometry for the same parameters.

Intense heavy ion beams open new possibilities in high-energy-density matter research. Due to the unique feature of the energy deposition process of heavy ions in dense matter (volume character of heating) it is possible to generate high entropy states in matter without the necessity of shock compression. Previously, such high entropy states could only be achieved by using the most powerful shock wave generators, like nuclear explosions or powerful lasers. In this paper this novel technique of heavy ion heating and expansion is proposed to explore new fascinating regions of the phase diagram, including the liquid phase, the evaporation region with the critical point, and strongly coupled plasmas.

The heavy ion synchrotron, SIS-18 (that has an 18 Tm magnetic rigidity), at the Gesellschaft fur Schwerionenforschung (GSI), Darmstadt is a unique facility worldwide that delivers intense beams of energetic heavy ions. The GSI has plans to extend its accelerator capabilities by building a new synchrotron (SIS-200) with a much higher magnetic rigidity of 200 Tm. According to the preliminary design considerations, the SIS-200 will generate a uranium beam that will consist of at least 1012 particles and that will be delivered in a 50 ns long pulse. This beam will be used to study various interesting problems, including fragmentation of the projectile ions while passing through solid matter and creation of high-density, strongly coupled plasmas. For the former type of studies, a particle energy of 1 GeV/u has been considered to be appropriate, while for the latter case, a lower value of 400 MeV/u has been found to be most suitable. In this paper we present, with the help of two-dimensional numerical simulatio...

We present experimental data showing an angular separation of laser accelerated proton beams. Using flat plastic targets with thicknesses ranging from 200 nm to 1200 nm, a laser intensity of 6×1020 W cm−2 incident with an angle of 10°, we observe accelerated protons in target normal direction with cutoff energies around 30 MeV independent from the target thickness. For the best match of laser and target conditions, an additional proton signature is detected along the laser axis with a maximum energy of 65 MeV. These different beams can be attributed to two acceleration mechanisms acting simultaneously, i.e., target normal sheath acceleration and acceleration based on relativistic transparency, e.g., laser breakout afterburner, respectively.