High Energy Density States In Matter Research Articles

Large Hadron Collider at CERN: Beams generating high-energy-density matter

This paper presents numerical simulations that have been carried out to study the thermodynamic and hydrodynamic responses of a solid copper cylindrical target that is facially irradiated along the axis by one of the two Large Hadron Collider (LHC) 7 TeV/ c proton beams. The energy deposition by protons in solid copper has been calculated using an established particle interaction and Monte Carlo code, FLUKA, which is capable of simulating all components of the particle cascades in matter, up to multi-TeV energies. These data have been used as input to a sophisticated two-dimensional hydrodynamic computer code BIG2 that has been employed to study this problem. The prime purpose of these investigations was to assess the damage caused to the equipment if the entire LHC beam is lost at a single place. The FLUKA calculations show that the energy of protons will be deposited in solid copper within about 1 m assuming constant material parameters. Nevertheless, our hydrodynamic simulations have shown that the energy deposition region will extend to a length of about 35 m over the beam duration. This is due to the fact that first few tens of bunches deposit sufficient energy that leads to high pressure that generates an outgoing radial shock wave. Shock propagation leads to continuous reduction in the density at the target center that allows the protons delivered in subsequent bunches to penetrate deeper and deeper into the target. This phenomenon has also been seen in case of heavy-ion heated targets [N. A. Tahir, A. Kozyreva, P. Spiller, D. H. H. Hoffmann, and A. Shutov, Phys. Rev. E 63, 036407 (2001)]. This effect needs to be considered in the design of a sacrificial beam stopper. These simulations have also shown that the target is severely damaged and is converted into a huge sample of high-energy density (HED) matter. In fact, the inner part of the target is transformed into a strongly coupled plasma with fairly uniform physical conditions. This work, therefore, has suggested an additional very important application of the LHC, namely, studies of HED states in matter.

The CERN Super Proton Synchrotron as a tool to study high energy density physics

An experimental facility named HiRadMat, will be constructed at CERN to study the impact of the 450 GeV c−1 proton beam generated by the Super Proton Synchrotron (SPS) on solid targets. This is designed to study damage caused to the equipment including absorbers, collimators and others in case of an accidental release of the beam energy. This paper presents two-dimensional numerical simulations of target behavior irradiated by the SPS beam. These numerical simulations have shown that the target will be completely destroyed in such an accident, thereby generating high energy density (HED) matter. This study therefore suggests that this facility may also be used for carrying out dedicated experiments to study HED states in matter.

Studies of thermophysical properties of high-energy-density states in matter using intense heavy ion beams at the future FAIR accelerator facilities: The HEDgeHOB collaboration

Intense beams of energetic heavy ions are believed to be a very efficient and novel tool to create states of High-Energy-Density (HED) in matter. This paper shows with the help of numerical simulations that the heavy ion beams that will be generated at the future Facility for Antiprotons and Ion Research (FAIR)[W.F. Henning, Nucl. Instr. Meth. B 214, 211 (2004)] will allow one to use two different experimental schemes to study HED states in matter. First scheme named HIHEX (Heavy Ion Heating and EXpansion), will generate high-pressure, high-entropy states in matter by volumetric isochoric heating. The heated material will then be allowed to expand isentropically. Using this scheme, it will be possible to study important regions of the phase diagram that are either difficult to access or are even unaccessible using traditional methods of shock compression. The second scheme would allow one to achieve low-entropy compression of a sample material like hydrogen or water to produce conditions that are believed to exist in the interiors of the giant planets. This scheme is named LAPLAS (LAboratory PLAnetary Sciences).

Proposed studies of strongly coupled plasmas at the future FAIR and LHC facilities: the HEDgeHOB collaboration

Detailed theoretical studies have shown that intense heavy-ion beams that will be generated at the future Facility for Antiprotons and Ion Research (FAIR) (Henning 2004 Nucl. Instrum. Methods B 214 211) at Darmstadt will be a very efficient tool to create high-energy-density (HED) states in matter including strongly coupled plasmas. In this paper we show, with the help of two-dimensional numerical simulations, the interesting physical states that can be achieved considering different beam intensities using zinc as a test material. Another very interesting experiment that can be performed using the intense heavy-ion beam at FAIR will be generation of low-entropy compression of a test material such as hydrogen that is enclosed in a cylindrical shell of a high-Z material such as lead or gold. In such an experiment, one can study the problem of hydrogen metallization and the interiors of giant planets. Moreover, we discuss an interesting method to diagnose the HED matter that is at the centre of the Sun. We have also carried out simulations to study the damage caused by the full impact of the Large Hadron Collider (LHC) beam on a superconducting magnet. An interesting outcome of this study is that the LHC beam can induce HED states in matter.

Numerical simulations and theoretical analysis of High Energy Density experiments at the next generation of ion beam facilities at Darmstadt: The HEDgeHOB collaboration

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 1 GeV/u uranium beam with an intensity, N = 10 10–10 12 ions that are delivered in a single bunch, 50 ns 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 1–4 mm. 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 (3–30 Mbar) 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.

Proposal for the Study of Thermophysical Properties of High-Energy-Density Matter Using Current and Future Heavy-Ion Accelerator Facilities at GSI Darmstadt

The subject of high-energy-density (HED) states in matter is of considerable importance to numerous branches of basic as well as applied physics. Intense heavy-ion beams are an excellent tool to create large samples of HED matter in the laboratory with fairly uniform physical conditions. Gesellschaft für Schwerionenforschung, Darmstadt, is a unique worldwide laboratory that has a heavy-ion synchrotron, SIS18, that delivers intense beams of energetic heavy ions. Construction of a much more powerful synchrotron, SIS100, at the future international facility for antiprotons and ion research (FAIR) at Darmstadt will lead to an increase in beam intensity by 3 orders of magnitude compared to what is currently available. The purpose of this Letter is to investigate with the help of two-dimensional numerical simulations, the potential of the FAIR to carry out research in the field of HED states in matter.

Studies of heavy ion-induced high-energy density states in matter at the GSI Darmstadt SIS-18 and future FAIR facility

This paper presents numerical simulation results of heating and compression of matter using intense beams of energetic heavy ions. In this study we consider different beam parameters that include those which are currently available at the heavy ion synchrotron, SIS18 at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt and those which will be available in the near future as a result of the upgraded facility. In addition to this, we carried out detailed calculations considering parameters of high-intensity beam which will be generated at the GSI future Facility for Antiprotons and Ion Research (FAIR facility) that has been approved by the German Government. These simulations show that by using the above ion beam parameter range, it will be possible to carry out very useful studies on the thermophysical properties of high-energy density (HED) states in matter. This scheme would make it possible to investigate those regions of the phase diagram that are either very difficult to access or even are unaccessible using the traditional methods of shock waves. Moreover, employing a hollow ion beam which has an annular (ring shaped) focal spot, it would be possible to achieve a low entropy compression of a test material like hydrogen, which is enclosed in a cylindrical shell of a high-density material such as lead or gold. These experiments will enable one to study the interiors of Giant planets, Jupiter and Saturn as well as to investigate the problem of hydrogen metallization.