H. Hora

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Kirk A Flippo

Los Alamos National Laboratory

University of Gothenburg

Dieter Hoffmann

Gaurav Mishra

Lorenzo Torrisi

University of Messina

J. Ullschmied

Yitzhak Maron

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Papers by H. Hora

Generation of multiply charged ions at low and high laser-power densities

by Jan Badziak and H. Hora

Plasma Physics and Controlled Fusion, 2003

The PERUN and PALS iodine laser systems and a Nd : YAG laser have been used for studies of ions e... more The PERUN and PALS iodine laser systems and a Nd : YAG laser have been used for studies of ions emitted from various single element laser plasmas, at both low (IL~109 W cm-2) and high (IL~1016 W cm-2) laser intensities. Sufficiently high current densities of low-charge ions, with energies only of hundreds of electronvolt, were produced for starting tests of

Fusion energy from plasma block ignition

Laser and Particle Beams, 2005

Generation of high speed dense plasma blocks is well known from hydrodynamic theory and computati... more Generation of high speed dense plasma blocks is well known from hydrodynamic theory and computations~PIC! with experimental confirmation by Badziak et al.~2005! since ps laser pulses with power above TW are available. These blocks may be used for fusion flame generation~thermonuclear propagation! in uncompressed solid state deuterium and tritium for very high gain uncomplicated operation in power stations. Hydrodynamic theory from computations from the end of 1970s to recent, genuine two fluid computations support the skin layer accelerations~SLA!, by nonlinear ponderomotive! forces as measured now in details under the uniquely selected conditions to suppress relativistic self-focusing by high contrast ratio and to keep plane geometry interaction. It is shown how the now available PW-ps laser pulses may provide the very extreme conditions for generating the fusion flames in solid state density DT.

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A new hydrodynamic analysis of double layers

Laser and Particle Beams, 1987

Analysis of experiments on energetic ions from laser produced plasmas with reference to hot electrons and pulsation

Czechoslovak Journal of Physics, 1992

The need for high]y charged heavy ions from projected particle accelerators has recently led to a... more The need for high]y charged heavy ions from projected particle accelerators has recently led to a re-evaluation of the complex processes of ion production in laser generated plasmas. Possible mechanisms for the production of intense beams of high charge state ions are investigated as is the experimental evidence for these mechanisms. The hypothesis that 20 keV ions are driven by "hot electrons" is not supported by experimental work to date. This work, on the other hand, suggests that 30ps pulsation is the basic mechanism for the acceleration of tantalum ions up fo charge state 8-t-whose energy increases linearly with charge state up to 24keV. For long pulses and charge states between 8-}-and 18n u, it appears that there is a secondary mechanism of electron impact ionisation by plasma electrons of approximately 200 eV in the plasma in front of the target, resulting in ions whose energy of around 24 keV is independent of charge state.

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The influence of pre-pulse plasma on ion and x-ray emission from Ta plasma produced by a high-energy laser pulse

by Jan Badziak, J. Wolowski, and H. Hora

Czechoslovak Journal of Physics, 2004

The paper describes studies of ion and x-ray emissions from plasma produced by the PALS laser sys... more The paper describes studies of ion and x-ray emissions from plasma produced by the PALS laser system at different parameters of pre-plasma generated by a laser pre-pulse. The plasma was produced by 0.4-ns laser pulses of about 140 J at 438 nm (3 rd harmonic frequency) focused on a slab Ta target. The main laser pulse was preceded by a pre-pulse having either 0.7 main-pulse energy. The main pulse was delayed by 0.6 ns, 1.2 ns, 2.3 ns, or 4.6 ns with reference to the prepulse. The characteristics of the ion streams (energies, charge states and angular distributions of ion emission) were investigated using diagnostics based on the time-of-flight method. The x-rays were measured using various types of semiconductor detectors covered with different filters. It was found that, at small delay times, Δt < 1 ns, the values of the fast ion parameters (e.g. mean ion energy, average charge state, and peak current density) as well as the soft and hard x-ray yields change slightly and that they distinctly decrease with the increasing Δt, excluding the peak ion current density, which, after attaining a shallow minimum at ∼2.5 ns, reaches its highest value at the longest Δt. At the longest delay times, we observed the generation of a high-current-density (> 0.2 A cm −2 at 1 m) ion stream having angular divergence and ion energy spread significantly smaller than those for the case without the pre-pulse.

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Generation of multiply charged ions at low and high laser-power densities

by Jan Badziak and H. Hora

Plasma Physics and Controlled Fusion, 2003