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Abstract: This paper presents detailed numerical simulations and theoretical analysis of different possible experimental schemes to study the thermophysical and transport properties of High Energy Density (HED) matter generated by the interaction of intense heavy ion beams. The considered beam parameters are those which will be available at the future Facility for Antiprotons and Ion Research (FAIR) at Darmstadt [W.F. Henneing, Nucl. Instrum. Methods, B214, (2004) 211]. This work has shown that an intense heavy ion beam can be used employing two very different configurations to study HED states in matter. In the first scheme, a sample material is uniformly and isochorically heated by the beam and the heated material is subsequently allowed to expand isentropically. Depending on the specific energy deposited in the material, one may access all the interesting physical states, including that of an expanded hot liquid (EHL), two-phase liquid–gas (2PLG) region, critical point (CP) parameters as well as strongly coupled plasma (SCP) states during the expansion. This scheme is named HIHEX (Heavy Ion Heating and EXpansion). We have considered a 1GeV/u uranium beam with an intensity, N =1010–1012 ions that are delivered in a single bunch, 50ns long. The particle intensity distribution in the transverse direction is assumed to be Gaussian with a full width at half maximum (FWHM) in the range of 1–4mm. We note that the estimated critical temperatures for many metals are very high which are very difficult to access using traditional techniques of shock compression of matter. Employing the proposed HIHEX scheme, one can easily achieve the required temperature by depositing corresponding specific energy in the sample. Solid as well as porous targets have been used in our study. In the second scheme, a sample material like frozen hydrogen that is enclosed in a cylindrical shell of a high-Z material like gold or lead, is imploded by the ion beam. This scheme is specially designed to generate multiple reflection of shocks in the target that leads to a low-entropy compression of the sample material. As a result of this, one achieves super-high densities (up to 30 times solid density) and ultrahigh pressures (3–30Mbar) in the hydrogen. If one uses a hollow beam with an annular focal spot, hydrogen is not directly heated by the ion beam that leads to a low final temperature (of the order of a few thousand K). This scheme is therefore suitable to study the problem of hydrogen metallization. In case one uses a circular focal spot, although the hydrogen is strongly heated by the beam, one still achieves a very high compression because the pressure in the surrounding shell is orders of magnitude higher than that in hydrogen. However, in this case the final hydrogen temperature is much higher (of the order of a few eV) than in the previous case. This configuration is thus suitable to study the interiors of the giant planets and is named LAPLAS (LAboratory PLAnetary Science). We have also analyzed the hydrodynamic stability of the LAPLAS target and we find that the Rayleigh–Taylor (RT) and Richtmeyer–Meshkov (RM) instabilities will not pose any serious problems to this scheme. [Copyright &y& Elsevier]

Abstract: High Energy Density Physics (HEDP) is one of the most important and interesting areas of science that spans over numerous branches of basic and applied physics. In this paper, we present an overview of different experimental techniques that have been used to study this field over the past decades. We also introduce a recently proposed novel technique to study HEDP that involves isochoric and uniform heating of extended targets using intense particle beams. The Gesellschaft für Schwerionenforschung (GSI), Darmstadt, is a leading laboratory worldwide that is well known for its unique accelerator facilities. The construction of a new accelerator complex named FAIR (Facility for Antiprotons and Ion Research) will substantially increase the accelerator capabilities of GSI, which will make it possible to employ this new technique to study HEDP. In this paper we highlight some of the salient features of this proposed new method. We also note that in order to organize the construction of experimental facilities at FAIR and later to carry out experiments on HEDP, an international collaboration, named, HEDgeHOB (High Energy Density Matter generated by Heavy IOn Beams), has been organized. The work presented in this paper has been done within the framework of the HEDgeHOB Collaboration. [Copyright &y& Elsevier]

Abstract: In this paper we discuss physical and technical issues of high-energy-density physics (HEDP) experiments with intense heavy ion beams that are being performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt. Special attention is given to a comparison of some recent results on expansion dynamics of evaporating lead that have been obtained in heavy ion beam driven HIHEX (Heavy-Ion Heating and Expansion) experiments at GSI-Darmstadt and in high-explosive driven shock wave loading and release experiments at IPCP–Chernogolovka. [Copyright &y& Elsevier]

Abstract: This paper presents an overview of the theoretical work that has been carried out during the past few years to assess the capabilities of intense heavy ion beams to induce states of High-Energy Density (HED) in matter. This work has shown that two different experimental schemes can be used to study HED physics employing intense ion beams. These schemes have been named HIHEX [Heavy Ion Heating and EXpansion] and LAPLAS [LAboratory PLAnetary Sciences], respectively. The first scheme involves isochoric and uniform heating and subsequent isentropic expansion of matter while the latter deals with low entropy compression of matter using multiple shock reflection technique. This work has been done within the framework of the HEDgeHOB [High Energy Density Matter Generated by Heavy Ion Beams] collaboration that has been formed to organize and facilitate construction of experimental facilities and later to perform experimental work in the field of HED matter at the future accelerator facility, FAIR [Facility for Antiprotons and Ion Research]. [Copyright &y& Elsevier]