Inertial confinement fusion using hohlraum radiation generated by heavy-ion clusters

Abstract

This paper discusses the feasibility of employing heavy-ion cluster beams to generate thermal radiation that can be used to drive inertial fusion capsules. The low charge-to-mass ratio of a cluster may allow the driver beam to be focused to a very small spot size with a radius of the order of 100 μm, while the low energy per nucleon (of the order of 10 keV) may lead to a very short range of the driver particles in the converter material. This would result in high specific power deposition that may lead to a very high conversion efficiency. The problem of cluster stopping in cold matter, as well as in hot dense plasmas has been thoroughly investigated. The conversion efficiency of cluster ions using a low-density gold converter has also been calculated over a wide range of parameters including converter density, converter geometry, and specific power deposition. These calculations have been carried out using a one-dimensional hydrodynamic computer code that includes a multigroup radiation transport scheme [Ramis et al., Comput. Phys. Commun. 49, 475 (1988)]. The problem of symmetrization of this radiation field in a hohlraum with solid gold walls has also been thoroughly investigated using a three-dimensional view factor code. The characteristics of the radiation field obtained by this study are used as input to capsule implosion calculations that are done with a three-temperature radiation-hydrodynamic computer code MEDUSA-KAT [Tahir et al., J. Appl. Phys. 60, 898 (1986)]. A reactor-size capsule which contains 5 mg deuterium–tritium (DT) fuel is used in these calculations. The problem of using a fuel mixture with a substantially reduced tritium content has also been discussed.

Energy loss of charged projectiles in a self-gravitating Lorentzian dusty plasma

“…[1][2][3] It is well known that when a test charge passes through an electron-ion plasma, it loses energy via the wave-particle interaction or simply by the interparticle collisions. [1][2][3] It is well known that when a test charge passes through an electron-ion plasma, it loses energy via the wave-particle interaction or simply by the interparticle collisions.…”

Direct-drive heavy ion beam inertial confinement fusion: a review, toward our future energy source

“…We presently see a reevaluation of the cluster ion beam (CIB) approach to ICF, including cluster ion acceleration, cluster fragmentation and target correlated stopping of cluster ions [87][88][89][90]. The CIB drive HIF demonstrates a potential for ICF through the enhanced and correlated ion stopping together with a lower q/A [87,88], which may relax the accelerator design further, compared with that for the conventional HIB accelerators. At the same time, the cluster ion source and the stable cluster acceleration should be further studied experimentally [90].…”

“…Studies at HIAF include EOS, material phase transitions, hydrodynamic behavior of matter, ion interaction with materials in the HED state [22]. At KEK, Japan, HEDP and ICF based on a cluster ion beam (CIB) are being considered [12,[87][88][89][90]103,116]. For example, Si clusters are efficiently formed in an ellipsoidal-shaped cell with a Si crystal at the focal point of the cell.…”

Peculiar behavior of Si cluster ions in a high-energy-density solid Al plasma

“…In ion beam inertial fusion application especially, a preferable ion speed may be about 0.1c ∼ 0.25c, that is, around 10 ∼ 50Mev/u [7][8][9]. Instead of ion beam, the cluster ion beam inertial fusion has been also proposed [10,11]. In the cluster ion beam (CIB) driven inertial fusion (CIF), it is expected to deposit the cluster beam energy in a small volume of the energy absorber of an inertial fusion fuel pellet by the correlated ion stopping enhancement in plasmas [12][13][14][15][16][17][18].…”

“…In the context of the inertial fusion [7][8][9][10][11], the ion beam or cluster ion beam input total energy is the order of MJ, and the input pulse length is the order of ∼10ns. Therefore, the temperature of the energy-absorber material of the fuel target becomes quickly high, for example, a few hundreds eV: T e E F [7,8,10,11]. The discussions above would be valid during the interaction time of the body of the input ion beam, except the very initial period.…”