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Background\ud Dissociative seizures are paroxysmal events resembling epilepsy or syncope with characteristic features that allow them to be distinguished from other medical conditions. We aimed to compare the effectiveness of cognitive behavioural therapy (CBT) plus standardised medical care with standardised medical care alone for the reduction of dissociative seizure frequency.\ud \ud Methods\ud In this pragmatic, parallel-arm, multicentre randomised controlled trial, we initially recruited participants at 27 neurology or epilepsy services in England, Scotland, and Wales. Adults (≥18 years) who had dissociative seizures in the previous 8 weeks and no epileptic seizures in the previous 12 months were subsequently randomly assigned (1:1) from 17 liaison or neuropsychiatry services following psychiatric assessment, to receive standardised medical care or CBT plus standardised medical care, using a web-based system. Randomisation was stratified by neuropsychiatry or liaison psychiatry recruitment site. The trial manager, chief investigator, all treating clinicians, and patients were aware of treatment allocation, but outcome data collectors and trial statisticians were unaware of treatment allocation. Patients were followed up 6 months and 12 months after randomisation. The primary outcome was monthly dissociative seizure frequency (ie, frequency in the previous 4 weeks) assessed at 12 months. Secondary outcomes assessed at 12 months were: seizure severity (intensity) and bothersomeness; longest period of seizure freedom in the previous 6 months; complete seizure freedom in the previous 3 months; a greater than 50% reduction in seizure frequency relative to baseline; changes in dissociative seizures (rated by others); health-related quality of life; psychosocial functioning; psychiatric symptoms, psychological distress, and somatic symptom burden; and clinical impression of improvement and satisfaction. p values and statistical significance for outcomes were reported without correction for multiple comparisons as per our protocol. Primary and secondary outcomes were assessed in the intention-to-treat population with multiple imputation for missing observations. This trial is registered with the International Standard Randomised Controlled Trial registry, ISRCTN05681227, and ClinicalTrials.gov, NCT02325544.\ud \ud Findings\ud Between Jan 16, 2015, and May 31, 2017, we randomly assigned 368 patients to receive CBT plus standardised medical care (n=186) or standardised medical care alone (n=182); of whom 313 had primary outcome data at 12 months (156 [84%] of 186 patients in the CBT plus standardised medical care group and 157 [86%] of 182 patients in the standardised medical care group). At 12 months, no significant difference in monthly dissociative seizure frequency was identified between the groups (median 4 seizures [IQR 0–20] in the CBT plus standardised medical care group vs 7 seizures [1–35] in the standardised medical care group; estimated incidence rate ratio [IRR] 0·78 [95% CI 0·56–1·09]; p=0·144). Dissociative seizures were rated as less bothersome in the CBT plus standardised medical care group than the standardised medical care group (estimated mean difference −0·53 [95% CI −0·97 to −0·08]; p=0·020). The CBT plus standardised medical care group had a longer period of dissociative seizure freedom in the previous 6 months (estimated IRR 1·64 [95% CI 1·22 to 2·20]; p=0·001), reported better health-related quality of life on the EuroQoL-5 Dimensions-5 Level Health Today visual analogue scale (estimated mean difference 6·16 [95% CI 1·48 to 10·84]; p=0·010), less impairment in psychosocial functioning on the Work and Social Adjustment Scale (estimated mean difference −4·12 [95% CI −6·35 to −1·89]; p

Physical review letters 119(20), 204801 (2017). doi:10.1103/PhysRevLett.119.204801, A novel method to determine the total hydrogen density and, accordingly, a precise plasma temperature in a lowly ionized hydrogen plasma is described. The key to the method is to analyze the energy loss of swift heavy ions interacting with the respective bound and free electrons of the plasma. A slowly developing and lowly ionized hydrogen theta-pinch plasma is prepared. A Boltzmann plot of the hydrogen Balmer series and the Stark broadening of the $H_β$ line preliminarily defines the plasma with a free electron density of (1.9$±$0.1)×10$^{16}$ cm$^{−3}$ and a free electron temperature of 0.8–1.3 eV. The temperature uncertainty results in a wide hydrogen density, ranging from 2.3 × 10$^{16}$ to 7.8 × 10$^{18}$ cm$^{−3}$. A 108 MHz pulsed beam of $^{48}$Ca$^{+10}$ with a velocity of 3.652 MeV/u is used as a probe to measure the total energy loss of the beam ions. Subtracting the calculated energy loss due to free electrons, the energy loss due to bound electrons is obtained, which linearly depends on the bound electron density. The total hydrogen density is thus determined as (1.9$±$0.7) × 10$^{17}$ cm$^{−3}$, and the free electron temperature can be precisely derived as 1.01$±$0.04 eV. This method should prove useful in many studies, e.g., inertial confinement fusion or warm dense matter., Published by APS, College Park, Md.

Recently a new high energy proton microscopy facility PRIOR (Proton Microscope for FAIR) has been designed, constructed and successfully commissioned at GSI Helmholtzzentrum f\"ur Schwerionenforschung (Darmstadt, Germany). As a result of the experiments with 3.5-4.5 GeV proton beams delivered by the heavy ion synchrotron SIS-18 of GSI, 30 um spatial and 10 ns temporal resolutions of the proton microscope have been demostrated. A new pulsed power setup for studying properties of matter under extremes has been developed for the dynamic commissioning of the PRIOR facility. This paper describes the PRIOR setup as well as the results of the first static and dynamic proton radiography experiments performed at GSI., Comment: 9 pages, 13 figures, submitted to Review of Scientific Instruments

Cylindrical cryogenic targets are required to carry out the Laboratory Planetary Science scheme of the experiments of the High Energy Density matter Generated by Heavy Ion Beams collaboration at FAIR. In this paper, for the first time a thorough analysis of the problem of such targets' fabrication, delivery and positioning in the center of the experimental chamber has been made. Particular attention is paid to the issue of a specialized cryogenic system creation intended for rep-rate supply of the High Energy Density matter Generated by Heavy Ion Beams experiments with the cylindrical cryogenic targets.

Intense ion beams from accelerators are now available to generate high energy density matter and to study astrophysical phenomena in the laboratory under controlled and reproducible conditions. A detailed understanding of interaction phenomena of intense ion- and laser radiation with matter is important for a large number of applications in different fields of science, extending from basic research of plasma properties to application in energy science and the investigation of processes occurring in stellar atmospheres or even in the interior of stars and planets. Energy loss processes of heavy ions in plasma and cold matter are important for the generation of high energy density states in general and especially in the hot dense plasma of an inertial fusion target. Of special interest are phase transitions and the associated time scales when matter passes the warm dense matter regime of the phase diagram at high density but relatively low temperature. We present an overview on recent results and developments of beam plasma, and beam matter interaction processes studied with heavy ion beams and laser beams combined with accelerator and nuclear physics technology. A natural example of hot dense plasma is provided by our neighbouring star the sun, and allows a deep insight into the physics of fusion, the properties of matter at high energy density, and is moreover an excellent laboratory for astroparticle physics. As such the sun’s interior plasma can even be used to probe the existence of novel particles and dark matter candidates with a combination of equipment and methods from accelerator technology and high resolution plasma spectroscopy.

The paper presents the results of precision measurements of the total stopping range and energy deposition function of 238U ions with specific energies E = 500 and 950 MeV/u in stainless steel and copper targets. The experiment was performed at the SIS-18 facility (GSI Darmstadt) in the experimental area Cave A in September 2004–May 2005. The measured energy deposition profiles are compared with calculations using the codes ATIMA, PHITS, SHIELD and SRIM.

Plasma targets for measuring energy loss and charge state distribution of heavy ions in non-ideal Ar-plasmas ( Γ -parameters 0.55–1.5) have been developed and the interaction with several ion species, C, Ar, Xe at 5.9 MeV / u , was studied. Here the results for 5.9 MeV / u C-ions are presented which have been understood just recently by considering the gas dynamics in the target due to the special configuration with the gap interaction zone for the plasma, which can be also simulated by the VarJet code.

European activities on inertial fusion energy are coordinated by “keep in touch activities” of the European Fusion Programme coordinated by the European Commission. There is no general inertial fusion program in Europe. Instead, a number of activities relevant to inertial fusion are carried out by university groups and research centers. The Helmholtz-Research Center GSI-Darmstadt (Gesellschaft fur Schwerionenforschung) operates accelerator facilities which provide the highest intensity for heavy ion beams and therefore key issues of ion beam driven fusion can be addressed. In addition to the accelerator facilities, one high-energy laser system is available (nhelix: nanosecond high-energy laser for ion experiments) and another one is under construction (PHELIX: petawatt high-energy laser for ion experiments). The heavy ion synchrotron facility, SIS18 (Schwer-Ionen-Synchrotron 18) recently delivered an intense uranium beam that deposits about 1 kJ/g specific energy in solid matter. Using this beam, experiments have been performed where solid Pb- and Ta-targets have been heated to the level of 1 eV. Experiments to study interaction mechanism of heavy ion beams with matter have been continued and are reported here.

Ion-beam-plasma-interaction plays an important role in the field of warm dense matter and inertial confinement fusion. A spherical theta pinch is proposed to act as a plasma target in various applications including a plasma stripper cell. One key parameter for such applications is the free electron density. A linear dependency of this density to the amount of energy transferred into the plasma from an energy storage was found by Teske. Since the amount of stored energy is known, the energy transfer efficiency is a reliable parameter for the design of a spherical theta pinch device. As the main assumption of a constant reflected plasma resistance is contradictory by the measured data, the traditional two models of energy transfer efficiency will lead to wrong results. From measurements, the parasitic resistance is derived as constant. Based on this key parameter, a new model is proposed. Due to no assumption, the new model is considered as exact. Further, a comparison of these three different models is given at a fixed operation voltage for the full range of working gas pressures. Due to the inappropriate assumptions included in the traditional models, one owns a tendency to overestimate the energy transfer efficiency whereas the other leads to an underestimation. Applying our new model to a wide spread set of operation voltages and gas pressures, an overall picture of the energy transfer efficiency results.

Interaction phenomena of intense ion- and laser radiation with matter have a large range of application in different fields of science, extending from basic research of plasma properties to applications in energy science, especially in inertial fusion. The heavy ion synchrotron at GSI now routinely delivers intense uranium beams that deposit about 1 kJ/g of specific energy in solid matter, e.g. solid lead. Our simulations show that the new accelerator complex FAIR (Facility for Antiproton and Ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. A natural example of hot dense plasma is provided by our neighbouring star the sun, and allows a deep insight into the physics of fusion, the properties of matter at high energy density, and is moreover an excellent laboratory for astroparticle physics. As such the sun's interior plasma can even be used to probe the existence of novel particles and dark matter candidates. We present an overview on recent results and developments of dense plasma physics addressed with heavy ion and laser beams combined with accelerator- and nuclear physics technology.

High intensity particle beams from accelerators induce high energy density states in bulk matter. The SIS-18 heavy ion synchrotron at GSI now routinely delivers intense Uranium beams that deposit about I kJ/g of specific energy in solid matter, e.g. solid lead. Due to the specific nature of the ion-matter interaction a volume of matter is heated uniformly with low gradients of temperature and pressure in the initial phase, depending on the pulse structure of the beam with respect to space and time. The new accelerator complex FAIR (Facility for Antiproton and ion Research) at GSI as well as beams from the CERN large hadron collider (LHC) will vastly extend the accessible parameter range for high energy density states. One special piece of accelerator equipment a superconducting high field dipole magnet, developed for the LHC at CERN is now serving as a key instrument to diagnose the dense plasma of the sun interior plasma, thus providing an extremely interesting combination of accelerator physics, plasma physics and astro-particle physics.

Plasma targets for measuring energy loss and charge-state distribution of heavy ions in non-ideal plasmas have been developed. Ar plasmas with Γ-parameters 0.55–1.5 could be realized and the interaction with several ion species studied. Here, the results for 5.9 MeV/u C ions are presented. The energy loss in plasma was reproduced in different experiments.

Interaction phenomena of intense ion and laser radiation with matter have a large range of application in different fields of science, from basic research of plasma properties to application in energy science. The hot dense plasma of our neighbouring star the Sun provides a deep insight into the physics of fusion, the properties of matter at high energy density, and is moreover an excellent laboratory for astroparticle physics. As such the Sun's interior plasma can even be used to probe the existence of novel particles and dark matter candidates. We present an overview on recent results and developments of dense plasma physics addressed with heavy ion and laser beams combined with accelerator and nuclear physics technology.

The paper presents the first experimental results obtained by using new gamma-quantum diagnostics for ion beam induced high energy density matter. Registration of γ-quantum output from the region of beam-target interaction with time resolution enables to pick-up information on density evolution of the target even if the ionization state of matter involved is unknown.

A new technique for X-ray spectromicroscopy of fast heavy ion radiation during the ion interaction with stopping media is presented using focusing spectrometers with spatial resolution. Spherically bent crystals of quartz and mica with small curvature radii, R=150 mm, and large apertures were used as dispersive elements in experiments on fast Ni ions with energies of 5.9 and 11.2 MeV/u which are being stopped in different media: Ar gas, SiO2-aerogels and solid quartz. Spectrally high (λ/Δλ=1000–3000) and spatially high (up to 10–100 μm) resolved Kα-satellite spectra of Ni projectiles as well as of the ionized stopping media were observed.

The X-ray spectral distribution of swift heavy Ti and Ni ions (11 MeV/u) observed inside aerogels (ρ = 0.1 g/cm3) and dense solids (quartz, ρ = 2.23 g/cm3) indicates a strong presence of simultaneous 3–5 charge states with one K-hole. We show that the theoretical analysis can be split into two tasks: first, the treatment of complex autoionizing states together with the originating spectral distribution, and, second, a charge-state distribution model. Involving the generalized line profile function theory, we discuss attempts to couple charge-state distributions.

The development of new construction materials for plasma reactor walls is crucial for the realisation and optimisation of fusion reactors. Promising candidates are SiC-based composite materials, because their excellent high temperature, mechanical and electrical properties may suit the high requirements. It is of special interest to investigate the behaviour of these materials under irradiation conditions. It is straightforward to use heavy ion irradiation to simulate damage doses, which could be achieved under normal reactor conditions with neutrons first in several years, since the damage spectra are very similar. Ni/SiC, Cu/SiC and Pt/SiC samples in bi-layer geometry were produced and irradiated by 150 keV Ar+ ions at fluences between 0.75 and 4.4×10 16 ions / cm 2 in a temperature range between 77 and 773 K. The concentration depth profiles were obtained with Rutherford backscattering spectrometry (RBS). Ballistic mixing in collision cascades were observed for all systems under investigation. In the case of the Ni/SiC system an additional mixing mechanism became dominant above room temperature. In the Pt/SiC samples radiation-induced phase formation was observed above 300°C. The sample surface was investigated with high resolution scanning electron microscopy (HRSEM) and atomic force microscopy (AFM). The measured surface roughening effects were taken into account at the calculation of the mixing lengths.

Several lines of evidence suggest that Fas-mediated apoptosis is involved in the CD4 T-cell depletion in human immunodeficiency virus-1 (HIV-1) infection. To investigate this, we studied changes in peripheral blood, early T-cell apoptosis and Fas expression after initiation of antiretroviral therapy (ART) in 18 HIV-1-infected individuals. Flow cytometric analysis was performed with ApostainTM and CD4, CD8 and Fas staining. Fas expression was quantified by standardized beads. The levels of CD4 and CD8 T cells with early apoptosis were increased comparably in HIV-1-infected individuals. Despite elevated CD4 T cell counts, no decline in early T-cell apoptosis could be detected during the first 8 weeks of ART. However, after 26 weeks of ART in five patients that showed a sustained reduction of viral replication there was a marked decrease in T cells with features of early apoptosis. No difference was found for Fas expression on early apoptotic T cells. Fas expression on CD4 and CD8 T cells was reduced after initiation of ART; this was independent of the CD4 T-cell trend and indicates that the immediate CD4 T-cell expansion during ART is probably not the result of a decreased rate of early apoptosis among peripheral blood CD4 T cells. However, preliminary data imply a long-term reduction of early T-cell apoptosis and Fas expression in patients who show a sustained reduction of viral replication.

Several lines of evidence suggest a dysregulation of the complement system in human immunodeficiency virus-1 (HIV-1) infected patients. The aim of this study was to elucidate whether CD4+ alveolar lymphocytes from HIV-1 infected patients show a loss of complement regulatory proteins that would render these cells susceptible to antibody-dependent complement-mediated cytotoxicity. We investigated the expression of complement regulatory (CD46, CD55, CD59) and complement receptor (CR1, CR2, CR3, CR4) proteins on alveolar cells by flow cytometry. Cells were obtained by bronchoalveolar lavage from 17 HIV-1 infected and 12 HIV-1 negative individuals. Expression of adhesion molecules (leucocyte functional associated antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1)) and CD30 were evaluated in patient subgroups. In addition, interleukin (IL)-1beta, tumour necrosis factor alpha (TNF-alpha), IL-4 and interferon gamma (IFN-gamma) concentrations were measured in supernatants of alveolar cells. We found a significantly reduced expression of CD46 and CD59 on CD4+ alveolar lymphocytes from HIV-1 infected individuals, whereas the expression of CR3, CR4, ICAM-1 and CD30 was increased. IL-1beta and TNF-alpha concentration in supernatants of alveolar cells was augmented in HIV-1 infected patients, but did not correlate with the expression of surface molecules. IFN-gamma concentration was also increased and showed an inverse relationship to the surface expression of CD30 on CD4+. Our data suggest that in human immunodeficiency virus-1 infection an increased level of activation is associated with a diminished expression of complement regulatory proteins on CD4+ alveolar lymphocytes. This phenomenon might contribute to the depletion of CD4+ lymphocytes and the local immunodeficiency in the pulmonary compartment.

Experiments are presented that demonstrate the high stopping power of fully ionized hydrogen plasma for low-energy heavy ions. A plasma with electron densities up to 7.1016 cm–3 at temperatures above 1 eV was created by an electrical discharge. In the described experiment, a stopping power of 1.08 GeV/(mg/cm2) was measured using singly charged krypton ions at 45–keV/u energy. The measured stopping power exceeds the corresponding value in cold hydrogen gas by a factor of 35. These measurements confirm the theoretical stopping power predictions close to the expected maximum in a fully ionized plasma.

Environmental impacts from tritium and active waste are examined and compared for four heavy-ion-driven inertial confinement fusion (IFC) reactor concept studies. The radiation exposure from tritium emissions during normal routine operation and for accidential release of 10%, of the tritium inventory in the target fabrication is determined and compared with regulatory limits. In normal operation, two of the ICF reactor concepts are, independently of the tritium model applied, always below the regulatory limit. For the 10% tritium release from the target fabrication, only one ICF reactor concept is around the limit for the early off-site dose (5 rem). Active waste from structural material of the reactor chamber and the coolant-breeder qualifies either for the waste classes A to C defined by IOCFR61 or geological disposal by deep geological burial. Chambers with carbon-based structural material (SiC and C-C composites) qualify mainly for waste class A. Stainless steel as a structural material leads to active waste that is at least partly subject to geological storage and the disposal conditions depend strongly on the type of stainless steel. Coolant-breeder media are class C and mixed waste.

Intense heavy ion beams have been used in recent years to study the properties of matter under extreme conditions. The intense heavy ion beams of the radio frequency accelerator MAXILAC at GSI were used at ion energies of 45 keV/u to produce the first heavy ion driven plasma and to study the hydrodynamic reactions of this plasma. Similar experiments at 300 MeV/u ion energy using the heavy ion synchrotron SIS have now proven to be successful. The understanding and modelling of ion beam driven plasmas requires a precise knowledge of the stopping power in a plasma. Thus, in parallel to the ion beam driven plasmas, the stopping power of a fully ionized hydrogen plasma has been investigated experimentally testing an ion energy range of 45 keV/u to 10 MeV/u at plasma densities from 1016 to 1019 cm−3. The stoppping power experiments revealed the principle of new stopping behavior of ions in a plasma. In comparison to cold, non-ionized matter an increased stopping in hydrogen plasma up to a factor 35 has been observed.

Classic HVDC systems are prone to voltage instability when operating on weak AC grids. Certain methods are available to cope with weak system conditions, one of which is VDCOL. This paper describes the implementation of a newly developed Automatic Voltage Stabilizer (AVS) in an existing CIGR´E Benchmark Model for HVDC Controls and compares its performance with the VDCOL method. The tools used for the study are the OPAL-RT real-time simulator and the PSCAD/EMTDC digital simulator. With AVS, the power transfer can be optimized and kept at or close to the steady state stability limit thereby compensating for deficiencies of VDCOL. Using two different simulation environments provides important information on their capabilities to develop and improve future power system controls. QC 20121016

Sub-millimetre wall thickness is foreseen for the vacuum tubes in the magnets of the superconducting dipoles of the SIS100 and SIS300 of the FAIR Project. The Bragg peak of the energy deposition by the U ions in these walls may lie dangerously close to the superconducting cables. Thus the precise knowledge of the dE/dx profile is essential for estimating the heat load by the lost ions in the vicinity of the superconducting wires. Here we present the preliminary results of the measurement of the U ion beam energy deposition profile in Cu and stainless steel targets and compare the measured data with the dE/dx calculations using different codes.

Intense heavy ion beams from the Gesellschaft fur Schwerionenforschung ~GSI, Darmstadt, Germany! accelerator facilities, together with two high energy laser systems: petawatt high energy laser for ion experiments ~PHELIX! and nanosecond high energy laser for ion experiments ~NHELIX! are a unique combination to facilitate pioneering beam-plasma interaction experiments, to generate and probe high-energy-density ~HED! matter and to address basic physics issues associated with heavy ion driven inertial confinement fusion. In one class of experiments, the laser will be used to generate plasma and the ion beam will be used to study the energy loss of energetic ions in ionized matter, and to probe the physical state of the laser-generated plasma. In another class of experiments, the intense heavy ion beam will be employed to create a sample of HED matter and the laser beam, together with other diagnostic tools, will be used to explore the properties of these exotic states of matter. The existing heavy ion synchrotron facility, SIS18, deliver an intense uranium beam that deposit about 1 kJ0g specific energy in solid matter. Using this beam, experiments have recently been performed where solid lead foils had been heated and a brightness temperature on the order of 5000 K was measured, using a fast multi-channel pyrometer that has been developed jointly by GSI and IPCP Chernogolovka. It is expected that the future heavy ion facility, facility for antiprotons and ion research ~FAIR! will provide compressed beam pulses with an intensity that exceeds the current beam intensities by three orders of magnitude. This will open up the possibility to explore the thermophysical and transport properties of HED matter in a regime that is very difficult to access using the traditional methods of shock compression. Beam plasma interaction experiments using dense plasmas with a G-parameter between 0.5 and 1.5 have also been carried out. This dense Ar-plasma was generated by explosively driven shockwaves and showed enhanced energy loss for Xe and Ar ions in the energy range between 5.9 to 11.4 MeV.

Interaction processes of heavy ions and ionized matter have been investigated experimentally. A Monte Carlo code to simulate charge exchange and energy loss processes in a plasma environment has been developed to plan the experiments, to analyze the results, and to investigate the influence of magnetic fields on the particle trajectories inside the plasma target. The first results of the beam plasma interaction experiments are: The stopping power of ionized matter is increased compared to that of cold, non-ionized matter. This effect is especially pronounced at low ion energies (E < 100 keV/u) where an enhancement factor of up to 40 has been observed. At higher energies (E > 1 MeV/u) this effect is less dramatic, but is still on the order of 2-3, depending on the ion species. The charge state of ions traversing a fully ionized plasma is increased due to reduced capture cross sections of free plasma electrons. It is possible to focus intense heavy ion beams of high magnetic rigidity using a plasma lens. This ideal focusing device achieves a high focusing power for ion beams almost comparable to optical systems for intense beams from high power lasers. Energetic ion beams are very well suited to heat cylindrical target volumes and to create a dense plasma. The characteristic inner-shell target and projectile X-rays provide a tool to analyze the hydrodynamic behavior of beam heated targets with space and time resolution.

The accelerator facilities at GSI, consisting of a high current radio frequency quadrupole accelerator (MAXILAC), a rf‐linac (UNILAC), a heavy ion synchrotron (SIS) and an experimental storage ring (ESR) provide unique opportunities to study beam target interaction phenomena over a wide range of beam energy. This range extends from 45 keV/u up to 2 GeV/u. Thus rf‐accelerator and beam‐target interaction physics issues for heavy‐ion‐beam driven inertial confinement fusion can be studied. Recent results of stopping power experiments at UNILAC verified an enhanced energy loss of heavy ions in a plasma of a factor three at beam energies of 1–6 MeV/u. Even bigger differences in stopping power and charge state between ionized and cold matter are expected for beam velocities of the same order of magnitude as the thermal electron velocities in a plasma. A new energy loss experiment in this parameter range has been started at MAXILAC. First results indicate a tremendous enhancement of energy loss in a plasma at beam energies below 45 keV/u.

The interaction of energetic multicharged ion beams with separately produced target plasmas is investigated within a projectile ion-target electron binary pattern. The validity conditions of the relevant standard model are asserted. A few extensions are suggested.

The public: definitions and perceptions The public is a difficult concept to grasp. It exhibits contradictory meanings: a collective abstract entity that is based on a “togetherness” founded on the exercise of reason; a cumulative heterogeneous phenomenon formed into an audience by certain kinds of specialised proceedings; or, another possibility, the driving force of action aimed at modifying something of the individuals that one wishes to reach. In all these cases, it is not a self-defined social collective. However, we constantly speak of the public's point of view. Can we really contemplate a situation in which the public could be thought of as a potential enunciator of a point of view? Or at least as an interlocutor in communication with the institutions of which it is the public? This article describes the division between the status of the members of the public engaged in interpersonal communications with representatives of the institution and the status of the public as a collective abstract entity engaged in a “communication” with the institution.

(1989). Experimental investigation of beam–plasma interactions enhanced stopping power plasma lens effect. Radiation Effects and Defects in Solids: Vol. 110, No. 1-2, pp. 49-53.

Photon counting measurements of the electroluminescence from switching metal/insulator/metal diodes show two types of pulses: namely δ and plateau shaped. These are strongly correlated with the similarly shaped respective current peaks in the ON state. The average efficiency (photons per electron) was estimated to be 1 × 10 -6 in the ON state and 5 × 10 -8 in the background. Long-term operation under different vacuum conditions showed significant changes in the shapes of the current-voltage characteristics and the correlated photon emission.

Transmission and energy losses of 2 MeV/u Carbon and Sulphur beams passing through a plasma target, have been extensively investigated. A hydrogen plasma ignited by an electrical discharge was coupled to the Orsay Tandem beam accelerator. Fluctuations in beam transmission have been observed and attributed to a magnetic focusing effect generated during the plasma evolution. Energy loss measurements were performed on the basis of time of flight techniques and indicate an enhanced stopping power of the plasma relative to its cold matter equivalent.

By coupling a hydrogen plasma to a Tandem accelerator, transmission and energy losses of 2 MeV/u carbon and sulfur beams passing through a plasma target have been investigated. Fluctuations in beam transmission have been observed and attributed to a plasma lens effect. Moreover, energy loss measurements indicate an enhanced stopping power of the plasma relative to its cold matter equivalent.

The energy loss heavy ions in a plasma environment was measured by a time-of-flight method (TOF). It was possible to determine the energy loss for six different ion sepcies, high 40 Ca, high 74 Ge, high 84 Kr, high 110 Pd, high 209 Pb and high 238 U, in a linear discharge plasma of hydrogen in Z-pinch geometry. The plasma parameters, ecectron density n, and temperature T sub e, were measured by spectroscopic methods and laser absorption. The maximum density and temperature are found to be 3x10 high 17 e high minus/square centimeter and 2.1 eV. respectively. Compared to cold hydrogen gas of the same particle density the energy loss in a plasma environments is enhanced by a factor of 2 or more. The experimental data are in good agreement with theoretical predictions.

The interaction of energetic multicharged ion beams with separately produced target plasmas is investigated within a projectile-ion-target-electron bin

Heavy-ion beams of Ar + and Kr + with currents of 4 mA and an energy of 45 keV/u were focussed to about 1 mm 2 . Thus, a specific deposition po

The present status of experimental facilities at GSI to investigate interation phenomena of heavy ion particle beams and a hot dense plasma is described. There are currently two experimental scenarios that are persued at GSI. In one experiment the heavy ion beam of UNILAC is injected into an externally created plasma to investigate energy loss and charge state distribution of heavy ions traversing a plasma target. The other experiment will use a very intense particle beam accelerated by five RFQ sections to heat gas targets up to temperatures of some eV. This experiment will produce a very homogeneous and dense plasma.

SPQR II is an interaction experiment designed to probe energy ‐and charge‐exchange of Cn+ ions at 2 MeV/a.m.u., flowing through a fully ionized plasma column of hydrogen with nl=1019 e‐cm−2 at T=5 eV.One expects a factor of two enhanced stopping over the cold gas case.

Enhanced energy loss of 333 MeV(238) U ions in a hydrogen discharge plasma with a high degree of ionization has been observed. The ion stopping in a plasma environment exceeds the stopping in cold matter by more than a factor of two. Measured stopping powers are in agreement with theoretical predictions for the energy loss of heavy ions in a hydrogen plasma.