The basic physics of nonrelativistic and electromagnetic ion stopping in hot and ionized plasma targets is thoroughly updated. Corresponding projectile-target interactions involve enhanced projectile ionization and coupling with target free electrons leading to significantly larger energy losses in hot targets when contrasted to their cold homologues. Standard stoppping formalism is framed around the most economical extrapolation of high velocity stopping in cold matter. Further elaborations pay attention to target electron coupling and nonlinearities due to enhanced projectile charge state, as well. Scaling rules are then used to optimize the enhanced stopping of MeV/amu ions in plasmas with electron linear densities nel ~ 10 -10 cm. The synchronous firing of dense and strongly ionized plasmas with the time structure of bunched and energetic multicharged ion beam then allow to probe, for the first time, the long searched enhanced plasma stopping and projectile charge at target exit. Laser ablated plasmas (SPQR1) and dense linear plasma columns (SPQR2) show up as targets of choice in providing accurate and on line measurements of plasma parameters. Corresponding stopping results are of a central significance in asserting the validity of intense ion beam scenarios for driving thermonuclear pellets. Other applications of note feature thorium induced fission, novel ion sources and specific material processing through low energy ion beams. Last but not least, the given ion beam-plasma target interaction physics is likely to pave a way to the production and diagnostics of warm dense matter (WDM).

The fragmentation of 95 MeV/u 12C and 75 MeV/u 13C projectiles, interacting with natural targets of different elements (9Be, \(^{\rm nat}\)Cu and 197Au for 12C, and 9Be, \(^{\rm nat}\)Ni, and 181Ta for 13C) and of various thicknesses has been investigated at GANIL, using the doubly achromatic magnetic spectrometer LISE. The projectile-like fragments transmitted at 0\(^\circ\) have been analysed using a silicon \(\Delta E\)-E telescope and the \(\Delta E\)-time-of-flight method. The results obtained with the thinnest targets are discussed in the scope of radioactive nuclear beam production. The fragment momentum distributions can be fitted by Gaussian peaks associated with exponential tails towards low momentum values. The experimental production yields are compared with the results of the simulation code LISE. It appears that this code reproduces satisfactorily the yields of nuclei close to the stability line, but strongly overestimates the production of very neutron-deficient nuclei.

Total charge-changing cross sections and cross sections for the production of B and Be fragments were directly measured for reactions induced by similar to110-250 MeV/nucleon C-12 ions in C, CH2, and H2O targets. Etched track detector (CR-3) was used, together with an automatic track measuring system and a track matching algorithm, to count and to identify the primary and secondary particles. A comparison of the present data and of previously measured cross sections with model predictions is carried out. For the total charge-changing cross section, a model developed at NASA gives the best agreement with the present results (about 3% on the average). However, for the production of fragments, the results of models deviate on average for all systems studied by 9-58 % from the data presented in this work for Z=5 and by 5-47 % for Z=4. The model known as NUCFRG2 is the most reliable in giving the closest values for fragmentation cross sections, 9 and 5% for B and Be fragments, respectively, for the systems studied in this work.

Total charge-changing cross sections and cross sections for the production of B and Be fragments were directly measured for reactions induced by $\ensuremath{\sim}110--250 \mathrm{M}\mathrm{e}\mathrm{V}/\mathrm{n}\mathrm{u}\mathrm{c}\mathrm{l}\mathrm{e}\mathrm{o}\mathrm{n}{ }^{12}\mathrm{C}$ ions in C, ${\mathrm{CH}}_{2},$ and ${\mathrm{H}}_{2}\mathrm{O}$ targets. Etched track detector (CR-3) was used, together with an automatic track measuring system and a track matching algorithm, to count and to identify the primary and secondary particles. A comparison of the present data and of previously measured cross sections with model predictions is carried out. For the total charge-changing cross section, a model developed at NASA gives the best agreement with the present results (about 3% on the average). However, for the production of fragments, the results of models deviate on average for all systems studied by 9--58 % from the data presented in this work for $Z=5$ and by 5--47 % for $Z=4.$ The model known as NUCFRG2 is the most reliable in giving the closest values for fragmentation cross sections, 9 and 5% for B and Be fragments, respectively, for the systems studied in this work.

Measurements of heavy-ion slowing down in matter differ in many aspects from experiments with light particles like protons and α-particles. An overview of the special experimental requirements, methods, data analysis and interpretation is presented for heavy-ion stopping powers, energy- and angular-straggling and ranges in the energy domain from keV/u up to GeV/u. Characteristic experimental results are presented and compared with theory and semiempirical predictions. New applications are outlined, which represent a challenge to continuously improve the knowledge of heavy-ion slowing down.

The stopping powers of six gaseous media have been measured for incident 40 MeV/u Te-125 heavy ions. The energy losses of ions in various "thicknesses" of gas have been accurately determined. The gases were confined in a cell. The amount of matter traversed by the ions was determined from temperature and pressure measurements. The beam energy before and after slowing down were measured using the LISE magnetic spectrometer at GANIL. These experimental gas stopping powers are lower by about 10% than the corresponding tabulated values for solid media. This means that the gas-solid effect is still significant at 40 MeV/u for Te ions. The projectile effective charges derived from these measurements depend on the target atomic number, thus confirming the trend observed in previous experiments performed with lighter ions or at lower energies. (C) 2000 Elsevier Science B.V. All rights reserved.

The synchronous firing of dense and strongly ionized plasmas with the time structure of bunched and energetic multicharged ion beams allows us to probe, for the first time, the long searched for enhanced plasma stopping and enhanced projectile charge at the target exit.Correlated ion stopping of charged debris resulting from the fragmentation of energetic cluster ions focusing on Au foam converters is considered for indirectly driving a thermonuclear capsule. The one-dimensional (1D) simulation of converter time evolution demonstrates a very high conversion efficiency of projectile energy into hard x-ray photons building up a very hot (T-r > 300 eV) thermal bath. Intense and energetic cluster ion beams thus demonstrate considerable potential as a novel driver for inertial confinement fusion.

Stacks consisting of thin CR-39 sheets sandwiched between thick lucite and water absorbers were perpendicularly bombarded by 12C ions at 200 and 244 MeV/u. Track radius distributions representing the charge composition of the fragmented beams were automatically measured by a particle track analysis system. After analysis of the nuclear charge distributions, the total charge removal cross-sections and elemental production cross-sections of fragments with atomic numbers from 5 to 3, were obtained down to the lower energies (∼50 and 100 MeV/u, respectively). It has been found that the measured total charge removal cross-section agrees with theoretical predictions within ∼10% and very well with previous experiments in corresponding energy regions. Two model calculations for production of B fragment are in good agreement with our measured data while a third model overestimates it by ∼12%. Theoretical cross-sections for Be and Li fragments differ strongly among the different models and from measured values.

Les ions lourds possédant des propriétés balistiques importantes tel que le pic de Bragg nécessitent une énergie importante pour atteindre une tumeur profonde. Aux énergies intermédiaires et relativistes, des réactions de fragmentation se produisent tout au long de leur trajet et donnent naissance à des fragments plus légers que le projectile. Ces derniers entraînent une dose résiduelle au-delà du pic de Bragg. Pour cette raison, les ions les plus intéressants en radiothérapie convergent vers les ions lourds - légers (C à Ne). Par ailleurs, pour une sécurité accrue du traitement, on envisage d'utiliser aussi des faisceaux d'ions radioactifs émetteurs β(+). Ceci permet de fournir l'image du volume réellement irradié en utilisant une caméra à positon. Dans ce contexte, nos travaux ont porté essentiellement sur le calcul de taux de production et de la section efficace des noyaux issus de la fragmentation du (12)C à 95 MeV/u et du (13)C à 75 MeV/u.

Heavy ions having interesting properties as Bragg's peak require an important en­ ergy in order to attain a deep tumor. At intermediate and relativist energies, fragmen­ tation reactions occur throughout their path and produce fragments lighter than the projectile. Consequently, the product fragments give a residual dose beyond the Bragg peak. For these reasons, the interesting ions in radiotherapy of cancer con

Heavy ions having interesting properties as Bragg's peak require an important energy in order to attain a deep tumor. At intermediate and relativist energies, fragmentation reactions occur throughout their path and produce fragments lighter than the projectile. Consequently, the product fragments give a residual dose beyond the Bragg peak. For these reasons, the interesting ions in radiotherapy of cancer converge toward heavy - light ions (C - Ne). Moreover, for a better treatment safety, it is envisaged also to use beta((+)) transmitting radioactive ion beams. This allows to provide the picture of the really irradiated volume by using a positon camera. In this context, our works essentially is concentrated on production rates and cross sections calculations for nucleus products in the fragmentation of ((12))C at 95 MeV/u and ((13))C at 75 MeV/u.

Using CR-39 plastic track detectors the range values of 16O ions at two different energies (initially in the beam line, 39.97 MeV/n and 69.98 MeV/n) were measured after escaping the beam pipe and found to be (3050 ± 40) μm and (8210 ± 90) μm, respectively. The longitudinal and projected angular spread of oxygen ions of an initial energy of 69.98 MeV/n in the region of the Bragg peak was derived from the measured geometrical parameters of tracks. Based on a calibration curve (etch rate ratio vs total linear energy transfer in CR-39) and the measured track length distribution at the range end of oxygen ions, the complete depth dose profile of a 67.7 MeV/n 16O beam in CR-39 (plateau, extended Bragg peak and residual ionization caused by projectile like fragments) was obtained.

The ballistic and radiobiological properties of ion beams (C to Ne) are most promising for radiotherapy of tumours which are deeply seated and radioresistant. Ion beams exhibit an advantageous depth-dose profile (Bragg curve), i.e. an increase of the energy deposition with penetration depth culminating as the sharp fall-off of the dose following the Bragg peak. Besides, the biological efficiency is significantly increased at the end of beam range. These properties imply a better physical selectivity and a tumour control of ion beams in comparison with photons or neutrons. Before performing an actual treatment, all the physical properties of the particular beam should carefully be determined since they are altered as the ions pass through tissue. In following this goal a number of experiments useful for planning cancer therapy with ion beams of /sup 16/O, /sup 19/F and /sup 20/Ne in the energy range from 40 MeV/n to 290 MeV/n have been performed and evaluated in our laboratories. The irradiated tissue was simulated by water and Plexiglas. CR-39 (C/sub 12/H/sub 18/O/sub 7/) plastic served both as a target and as an etched track detector. From these experiments the following parameters have been obtained: (i) the partial cross-sections and yields of primary beam fragmentation leading to the production of lower Z ions, (ii) fluences and linear energy transfer (LET) along the penetration path, (iii) beam ranges and (iv) complete depth-dose profiles, including range stragglings and residual ionization formed due to longer range fragments. In the present contribution some selected examples of our results are given and briefly discussed.

The stopping powers of gases have been measured for incident 24 MeV/u 238U and 29 MeV/u 208Pb projectiles using the LISE spectrometer at GANIL. The results show the persistence of the 20% gas-solid effect observed at lower energy. The effective charges derived from these measurements depend on the atomic number of the target in a way very similar to that observed for solid degraders.