Search

Plants are often subjected to DNA damage due to a range of environmental and internal factors in the natural world. Among these factors, DNA double strand breaks（DSBs）have the most serious consequences to plants. If these DSBs are repaired improperly, which may result in genome instability, gene mutations, and even cell death. On one hand, plants have evolved a powerful and well-organized damage repair mechanism to ensure overall survival and normal reproduction. On the other hand, based on the fault-tolerance and mutagenicity of the repair process, a series of techniques such as T-DNA insertion, gene editing, and physical mutagenesis have been widely used for variety improvement in plants and animals. Compared with mammals, reports on DSBs repair pathways and their molecular mechanisms in plants are limited. In this paper, we review the responses of plants to DSBs damage and the main repair mechanisms, and we also focus on the recent advances in alternative end joining（Alt-EJ）, whose mechanism has not yet been fully revealed. In addition, we discuss the characteristics and multi-pathway options of DSBs repair in plants induced by heavy ion beams irradiation, and the progress of gene editing technology based on different DSBs repair pathways. This study aims to provide reference for understanding the molecular mechanism of plant DSBs damage response and developing efficient biological breeding technology. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa L.) holds significant importance as a staple food crop, and its continual improvement plays a crucial role in sustainable advancement of agriculture and food security in China. Radiation mutagenesis technology offers an effective approach for breeding high-yield, superior-quality, and stress-resistant rice varieties, thereby contributing positively to the independent innovation of China's seed industry. This study provides a comprehensive review on the progress and notable achievements made in the field of radiation-induced mutation breeding of rice in China over the past two decades. It encompasses various aspects, including the application of various types of radiation sources for radiation mutagenesis in rice, establishment of reliable screening methods, progress in understanding the molecular mechanisms underlying radiation-induced mutation, particularly through genomic variation studies. Additionally, the study highlights the development of a rice mutant bank comprising diverse phenotypes such as yield, resistance, and quality, along with the identification of related gene mutations. Furthermore, it discusses the creation of new varieties through radiation mutagenesis. Looking ahead, this technology will further contribute to the cultivation of higher yielding rice varieties adaptable to different environments and possess superior quality, while also creating new germplasms for gene function research in China.

The acceleration of super-heavy ions from an ultra-thin lead target irradiated by a femtosecond laser pulse with an intensity in the range of ∼1022â€"1023 W cmâˆ'2 was investigated using an advanced 2D3V particle-in-cell code. It is shown that by properly selecting the laser pulse parameters, it is possible to produce a practically single-charge Pb ion beam with multi-GeV ion energies and the laser-to-ions energy conversion efficiency approaching 30%. At the laser intensity of 1023 W cmâˆ'2, Pb ions with the charge state Z = 72 carry over 90% of the total energy of all ions, while the peak intensity and peak fluence of the Pb+72 ion beam are at least two orders of magnitude higher than for other types of ions. In addition, the Pb+72 ion beam is more compact and has a smaller angular divergence than those for other types of ions. The above properties of the Pb+72 ion beam mean that further energy-efficient purification of the beam from other types of ions is possible, even in simple ion transport and selection systems. [ABSTRACT FROM AUTHOR]

• Compared with gamma rays irradiation, heavy ion beams had stronger inhibitory effects on the growth of Astragalus mongholicus Bunge seedlings, while having less effects on antioxidase and physiological response. • The suitable doses of heavy ion beams and gamma rays irradiations for Astragalus mongholicus Bunge seeds were 200–250 Gy and 400 Gy, respectively. • 50 Gy heavy ion beams and 100 Gy gamma rays irradiations could significantly stimulate the accumulation of flavonoids in Astragalus mongholicus Bunge. Astragalus mongholicus Bunge (A. mongholicus) is a perennial herb in the Fabaceae family. Its dried rhizome has been used in clinical practice in China for more than 2000 years. However, the limited germplasm resources and unstable quality of A. mongholicus have limited its large-scale cultivation and wide application. Therefore, there is an urgent need to breed stable varieties. At present, heavy ion beams (HIBs) and gamma rays are important mutagenesis tools applied in medicinal plants. The aim of this investigation was to assess the effects of various doses (0, 50, 100, 200, and 400 Gy) of HIBs and gamma rays on the development, physiological reaction, and secondary metabolite accumulation of A. mongholicus. The findings indicated that the LD 50 of the A. mongholicus seeds to HIBs and gamma rays was 200–250 Gy and 400 Gy, respectively. As the radiation dose increased, there was a subsequent increase in the inhibition of seedling height, plant diameter, and number of branches and leaves, as well as a decrease in the chlorophyll a, b, and carotenoid contents of leaves. Additionally, the chlorophyll fluorescence parameter NPQ and flavonoid contents (total flavonoids, Calycosin-7-glucoside, Calycosin, Ononin, and Methylnissolin-3-O-glucoside) were also affected, which resulted in a distinct decrease in Y(II) values and diverse levels of elevation in leaf MDA content, SOD, and POD activities. Differently, CAT activity was substantially reduced, except for 50 Gy HIBs irradiation. Overall, upon the same dose of the two radiation qualities, HIBs had a stronger inhibitory effect on the growth of Astragalus seedlings, but less effect on antioxidant enzymes and physiological responses. There was no difference between two radiation qualities in increasing trend of flavonoid composition. The present study showed that HIBs is more beneficial for A. membranaceus mutation breeding research and would be promising tool for A. mongholicus mutation breeding. [ABSTRACT FROM AUTHOR]

The dynamics of charge-state fractions of sulfur-ion beams stripped by carbon foils at 2.0 MeV/u is investigated as a function of the initial-ion charge state q 0 of the incident beam using experimental data and theoretical calculations. Experimental dependencies of the ion fractions, mean charges and equilibrium foil thicknesses on q 0 are explained using the BREIT code, based on the analytical solution of the balance rate equations, as well as the ETACHA code. Experimental equilibrium charge-state distribution is qualitatively reproduced by both codes, demonstrating the capability of their approaches to the density effect. It is shown experimentally and theoretically that the non-equilibrium charge-state fractions and equilibrium foil thicknesses strongly depend on the initial ion charge q 0. [ABSTRACT FROM AUTHOR]

The dynamics of charge-state fractions of Au- and U-ion beams, penetrating hydrogen plasmas, is investigated for 1.4 and 3.6 MeV/u ion energies and plasma electron temperatures T e = (0.6 − 3.0) eV and densities N e =(1016 − 1020) cm−3. Calculations of the fractions as a function of the plasma thickness are performed by solving the balance rate equations with calculated ionization and recombination rates including those for dielectronic recombination (DR). The DR rates are calculated by the recently created computer code DRIMP using the fully relativistic multi-configuration approach and the so-called shifted Maxwellian velocity distribution function. Calculated by this method DR rates of Au- and U-ion beams passing through a hydrogen plasma are presented for the first time. Using the results obtained, the temperatures T e and densities N e are found at which the equilibrium mean charges q ̄ of Au- and U-ion beams are maximal for hydrogen-plasma length L ≤ 100 cm. Dependencies of the plasma equilibrium thicknesses X e q on the initial charge q 0 of incident ions are investigated, and it is found that X e q values are minimal at q 0 ≈ q ̄ . [ABSTRACT FROM AUTHOR]

We build upon recent work [1] that presented simulations of heavy ion beams' passive range lengthening in directly-driven DT targets by now raising the ion energy over the course of the drive to follow the ablation front inward. We have scaled the target from ref. [1] to reactor grade and have chosen a higher-energy driving ion species to reduce beam perveances. While an arbitrarily strong shock cannot compress the fuel by more than a finite factor (4X in a perfect monatomic gas), there is no bound on the entropy it can add. We present 1-D implosion calculations that demonstrate the approach to adiabatic compression with an increasing number of shocks tailored to keep the fuel nearly Fermi degenerate. We have studied capsule performance using either two discrete ion beam energies or a steadily ramped main pulse energy. These simulations show that a linear energy ramp reduces heating of the fuel early in the main pulse and improves coupling as ablated plasma accumulates. [1] B.G. Logan, L.J. Perkins, and J.J. Barnard, Phys. Plasmas 15, 072701 (2008).

1-D Lasnex calculations show efficient (15 to 20percent) hydro-coupling of heavy ion beams to direct drive targets without hohlraums at less than 1 MJ drive energy. Beam symmetry studies show that 60 beams may suffice with rotated beam spots on the ablator. NIF scale capsules with low aspect ratio A < 2 for robust RT stability show 1-D gains ~; 50 at drive energies of 350 to 450 kJ. Application to small heavy ion fusion test reactors with ~; 10 MWe, and to small fission fusion hybrids @ ~; 30 MWe net power scale are considered.

The dynamics of relativistic uranium-ion beams stripped by foils from Be to Au is investigated in the 100–500 MeV/u energy range. Calculations of the charge-state distributions of uranium fractions as a function of foil thickness are performed using the BREIT code, based on the analytical solution of the balance rate equations for the ion charge-state fractions. Relativistic electron-loss and electron-capture cross sections, required for BREIT as input data, are calculated for interactions of U q + ions, q = 65–92, colliding with Be, C, Al, Ti, Cu, Mo, W, and Au atoms. The beam energy losses are found to be rather small, less than 20%, and are not accounted for in calculations. Calculated charge-state distributions are compared with available experimental data, obtained at the GSI (Gesellschaft für Schwerionenforschung) and BEVALAC (Bevatron Linear Accelerator) facilities, and with calculations by the GLOBAL code created at GSI.The optimal conditions are predicted for production of bare, H-like, He-like and Li-like uranium ions with the largest probabilities. Dependencies of the equilibrium thicknesses for uranium charge-state fractions on the initial charge of incident ions are investigated. [ABSTRACT FROM AUTHOR]

Abstract Tandem particle accelerators produce beams of atomic nuclei which are used for nuclear physics or materials science experiments. The U.S. Naval Academy tandem has predominately been used only for proton beams during the past 27 years. This project developed beams of projectiles more massive than helium for the first time and used them for materials science applications. Special scattering chambers were developed for ion implantation and the study of scintillating materials. [ABSTRACT FROM AUTHOR]

The impact of heavy ion energy on charge yield in silicon dioxide was investigated by irradiating power VDMOSFETs with heavy ions at energies from 3 to 25 MeV/amu. The ion charge yield was determined by analyzing the gate voltage shifts of power VDMOSFETs induced by irradiation with 60Co $\gamma $ -rays and several different heavy ion species. A strong dependence of the charge yield on the ion energy is revealed. The charge yield at ion energy of 25 MeV/amu is greater by nearly an order of magnitude than that at the ion energy of 3 MeV/amu. The results are consistent with simulations of heavy ion track structures for low- and high-energy ions. [ABSTRACT FROM AUTHOR]

The efficient focusing, bunching and acceleration of high current, low energy heavy ion beams in an RFQ accelerator have been investigated. The considerations on the choice of the working frequency for increasing the beam current are introduced. Designed using an unconventional procedure, this 20 emA RFQ will be able to work with A / q ≤ 60 ion beams in the β range of 0.002–0.016. The beam dynamics simulation shows that the design fulfills all requirements with good beam quality and a compact structure. [ABSTRACT FROM AUTHOR]

A future thermonuclear fusion reactor relies on the real-time control of, among others, instabilities and plasma position. At the ISTTOK tokamak, a novel approach of a real-time diagnostic system to control the vertical plasma position (in a 100- \mu \texts closed-loop) was implemented by: 1) developing the heavy ion beam diagnostic (HIBD) to perform the position measurement and 2) combining data processing on a field-programmable gate array and Multithreaded Application Real-Time executor software framework. The results of this implementation have demonstrated the successful control of the plasma position using the HIBD. It was proven that the HIBD can be used to measure the ISTTOK vertical plasma position and to provide feedback in real time. In this paper, the overall implementation and integration is described and the experimental results are presented. [ABSTRACT FROM AUTHOR]

The response of plants to radiation is an essential topic in both space plant cultivation and mutation breeding by radiation. In this study, heavy ion beams (HIB) generated by the ground accelerator and X-rays (XR) were used as models of high linear energy transfer (LET) and low LET radiation to study the molecular response mechanism of Platycodon grandiflorus (P. grandiflorus) seedlings after irradiation. The gene and protein expression profiles of P. grandiflorus after 15 Gy HIB and 20 Gy XR radiation were analyzed by transcriptome and proteome. The results showed that the number of differentially expressed genes (DEGs) induced by HIB radiation was less than that of XR group, but HIB radiation induced more differentially expressed proteins (DEPs). Both HIB and XR radiation activated genes of RNA silencing, double-strand break repair and cell catabolic process. DNA replication and cell cycle related genes were down-regulated. The genes of cell wall and external encapsulating structure were up-regulated after HIB radiation. The gene expression of protein folding and glucan biosynthesis increased after XR radiation. Protein enrichment analysis indicated that HIB radiation resulted in differential protein enriched in photosynthesis and secondary metabolite biosynthesis pathways, while XR radiation induced differential protein of glyoxylate and dicarboxylate metabolism and carbon metabolism. After HIB and XR radiation, the genes of antioxidant system and terpenoid and polyketide metabolic pathways presented different expression patterns. HIB radiation led to the enrichment of non-homologous end-joining pathway. The results will contribute to understanding the biological effects of plants under space radiation., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest., (Copyright © 2023 The Committee on Space Research (COSPAR). Published by Elsevier B.V. All rights reserved.)

The design and the performance of the Ionization Beam Profile Monitor (IBPM) operating on the residual gas ionization principle are described. The main advantage of the constructed device is the non-contact measuring method. Operating under hard environmental conditions it delivers the information about the primary beam position, profile and intensity in “on-line” regime. It was tested under high gamma and neutron radiation conditions and changing vacuum using a range of low and intermediate energy beams at the beam current of a few nA to 15 μA. The diagnostic box was located in the vicinity of the accelerator, where the neutron flux was over 106 n/cm2s. It was found out that the device is capable to operate in vacuum in the range of 10-6÷10-3 mbar without the loss of the resolution power at the beam current as low as a few nA. The IBPM is prospective for beam profile monitoring due to long time. Emergency situations do not lead to decrease of its operability.

The propagation induced pulse broadening (PIPB) effect of the SET pulses in 65nm bulk inverter chains is characterized and discussed generated by the heavy ion microbeam. An odd-even separated layout placement strategy is implemented in the test chip to improve the resolution of the broadened width measurement. The experiment results show that bigger transistor size is able to inhibit the PIPB effect better, but the well structure and layout topology show insignificant influence on the PIPB effect of the SET pulses generated by the low LET heavy ions. [ABSTRACT FROM PUBLISHER]

The design of a compact all-permanent magnet electron cyclotron resonance (ECR) ion source injector for the ReAccelerator Facility (ReA) at the Michigan State University (MSU) National Superconducting Cyclotron Laboratory (NSCL) is currently being carried out. The ECR ion source injector will complement the electron beam ion trap (EBIT) charge breeder as an off-line stable ion beam injector for the ReA linac. The objective of the ECR ion source injector is to provide continuous-wave beams of heavy ions from hydrogen to masses up to 136 Xe within the ReA charge-to-mass ratio ( Q / A ) operational range from 0.2 to 0.5. The ECR ion source will be mounted on a high-voltage platform that can be adjusted to obtain the required 12 keV/u injection energy into a room temperature radio-frequency quadrupole (RFQ) for further acceleration. The beam line consists of a 30 kV tetrode extraction system, mass analyzing section, and optical matching section for injection into the existing ReA low energy beam transport (LEBT) line. The design of the ECR ion source and the associated beam line are discussed. [ABSTRACT FROM AUTHOR]

Equilibrium charge state distributions of stable 60 Ni, 59 Co, and 63 Cu beams passing through a 1 μm thick Mo foil were measured at beam energies of 1.84 MeV/u, 2.09 MeV/u, and 2.11 MeV/u respectively. A 1-D position sensitive Parallel Grid Avalanche Counter detector (PGAC) was used at the exit of a spectrograph magnet, enabling us to measure the intensity of several charge states simultaneously. The number of charge states measured for each beam constituted more than 99% of the total equilibrium charge state distribution for that element. Currently, little experimental data exists for equilibrium charge state distributions for heavy ions with 19 ≲ Z p , Z t ≲ 54 ( Z p and Z t , are the projectile’s and target’s atomic numbers respectively). Hence the success of the semi-empirical models in predicting typical characteristics of equilibrium CSDs (mean charge states and distribution widths), has not been thoroughly tested at the energy region of interest. A number of semi-empirical models from the literature were evaluated in this study, regarding their ability to reproduce the characteristics of the measured charge state distributions. The evaluated models were selected from the literature based on whether they are suitable for the given range of atomic numbers and on their frequent use by the nuclear physics community. Finally, an attempt was made to combine model predictions for the mean charge state, the distribution width and the distribution shape, to come up with a more reliable model. We discuss this new “combinatorial” prescription and compare its results with our experimental data and with calculations using the other semi-empirical models studied in this work. [ABSTRACT FROM AUTHOR]

Purpose: IAEA TRS-398 notes that cylindrical ionization chambers are preferred for reference proton dosimetry. If a cylindrical ionization chamber is used in a phantom to measure the dose as a function of depth, the effective point of measurement (EPOM) must be taken into account. IAEA TRS-398 recommends a displacement of 0.75 times the inner cavity radius (0.75R) for heavy ion beams. Theoretical models by Palmans and by Bhullar andWatchman confirmed this value. However, the experimental results vary from author to author. The purpose of this study is to accurately measure the displacement and explain the past experimental discrepancies. Methods: In this work, we measured the EPOM of cylindrical ionization chambers with high accuracy by comparing the Bragg-peak position obtained with cylindrical ionization chambers (PTW 30013, PTW 31016) to that obtained using a plane-parallel ionization chamber (PTW 34045). Results: The EPOMs of PTW 30013 and 31016 were shifted by 0.92±0.07R with R = 3.05 mm and 0.90±0.14R with R = 1.45 mm, respectively, from the reference point toward the source. Conclusions: The EPOMs obtained were greater than the value of 0.75R proposed by the IAEA TRS-398 and the analytical results. [ABSTRACT FROM AUTHOR]

Purpose: The use of motion mitigation techniques such as tracking and gating in particle therapy requires real-time knowledge of tumor position with millimeter precision. The aim of this phantombased study was to evaluate the option of diagnostic ultrasound (US) imaging (sonography) as real-time motion detection method for scanned heavy ion beam irradiation of moving targets. Methods: For this pilot experiment, a tumor surrogate was moved inside a water bath along twodimensional trajectories. A rubber ball was used for this purpose. This ball was moved by a robotic arm in two dimensions lateral to the heavy ion beam. Trajectories having a period of 3 s and peak to peak amplitude of 20 mm were used. Square radiation fields of 3 × 3 cm² were irradiated on radiosensitive films with a 200 MeV/u beam of calcium ions having a FWHM of 6 mm. Pencil beam scanning and beam tracking were employed. The films were attached on the robotic arm and thus moved with the rubber ball. The position of the rubber ball was continuously measured by a US tracking system (Mediri GmbH, Heidelberg) and sent to the GSI therapy control system (TCS). This position was used as tracking vector. Position reconstruction from the US tracking system and data communication introduced a delay leading to a position error of several millimeters. An artificial neural network (ANN) was implemented in the TCS to predict motion from US measurements and thus to compensate for the delay. Results: Using ANN delay compensation and large motion amplitudes, the authors could produce irradiation patterns with a few percent inhomogeneity and about 1 mm geometrical conformity. Conclusions: This pilot experiment suggests that diagnostic US should be further investigated as dose-free, high frame-rate, and model-independent motion detection method for scanning heavy ion beam irradiation of moving targets. [ABSTRACT FROM AUTHOR]

Purpose: It is essential to consider large-angle scattered particles in dose calculation models for therapeutic carbon-ion beams. However, it is difficult to measure the small dose contribution from large-angle scattered particles. In this paper, the authors present a novel method to derive the parameters describing large-angle scattered particles from the measured results. Methods: The authors developed a new parallel-plate ionization chamber consisting of concentric electrodes. Since the sensitive volume of each channel is increased linearly with this type, it is possible to efficiently and easily detect small contributions from the large-angle scattered particles. The parameters describing the large-angle scattered particles were derived from pencil beam dose distribution in water measured with the new ionization chamber. To evaluate the validity of this method, the correction for the field-size dependence of the doses, 'predicted-dose scaling factor,' was calculated with the new parameters. Results: The predicted-dose scaling factor calculated with the new parameters was compared with the existing one. The difference between the new correction factor and the existing one was 1.3%. For target volumes of different sizes, the calculated dose distribution with the new parameters was in good agreement with the measured one. Conclusions: Parameters describing the large-angle scattered particles can be efficiently and rapidly determined using the new ionization chamber. The authors confirmed that the field-size dependence of the doses could be compensated for by the new parameters. This method makes it possible to easily derive the parameters describing the large-angle scattered particles, while maintaining the dose calculation accuracy. [ABSTRACT FROM AUTHOR]

Abstract: Heavy ion beams have favorable energy deposition behavior because they can penetrate and deposit their energy well inside the target. Ion beams have potential uses in fields including heavy ion beam fusion, high-energy density physics and material processing. Intense heavy ion beams can generate high-energy density matter in the laboratory under extreme density and pressure conditions. Additionally, in heavy ion fusion, a stringent requirement for successful fuel ignition and sufficient fusion energy release is that the ion energy deposition profiles are calculated precisely in the energy absorber layer. In this work, the OK2 code was used to simulate the heavy ion beam energy deposition in various target materials, and a computer program was written to provide 3D visualization of the results. The heavy ion beams used in this work were composed of lead, uranium, and cesium ions with energies of 8GeV and carbon ions with energies of 5MeV. The targets included two shapes: a monolayer sphere that can be used in direct-driven fusion and a cylindrical shape that is common in indirectly driven heavy ion fusion. [Copyright &y& Elsevier]

X-ray emission from Xe30+ ions at 350–600 keV impacting on an Au target was investigated at the Heavy Ion Research Facility at Lanzhou. Characteristic X-rays of Xe ions at energy of about 1.65 keV were observed. This X-ray emission is induced by the decay of very high Rydberg states of Xe ions. It was also found that the yield of such characteristic X-rays is decreasing with increasing the projectile kinetic energy. Simultaneously, the yield of the characteristic Au X-rays from the M shell increases also. These phenomena are qualitatively analyzed with the classical Coulomb over the Barrier Mode (COBM) for highly charged ions interacting with solid state surfaces. [ABSTRACT FROM AUTHOR]

The design and the performance of the primary beam diagnostic system operating on a non-intercepting measurement method are described. It was assembled for operation under harsh environmental conditions. The main part of the beam detection system is the Ionization Beam Profile Monitor (IBPM) operating on the ionization of the residual gas principle. The primary beam diagnostic system provides data sufficient to plot spatial distributions of the beam current in the monitored area operating in on-line regime. It was used to monitor the profiles of ^7Li, ^11B, ^32S beams in the energy range of 30 \div 50 AMeV and ^20Ne, ^40Ar, ^86Kr, ^132Xe beams at 4 \div 5 AMeV. All measurements were performed under the conditions of high gamma and neutron flux. The diagnostic box was located in the vicinity of the accelerator, where the neutron flux was over 10^6\ neutrons/cm^2s. The beam current was in the range of a few nA up to 15 \muA. The device operates in vacuum on the level of 10^-6\div 10^-3\ mbar without loss of resolution power at the beam current as low as a few nA. Long operation time and emergency situations do not lead to decrease of its operability. [ABSTRACT FROM AUTHOR]

The HypHI experiment for precise hypernuclear spectroscopy with induced reactions of stable heavy ion beams and rare isotope beams is currently under preparation at GSI. The main goal of the HypHI project is to study neutron and proton rich hypernuclei and to measure directly hypernuclear magnetic moments at GSI and FAIR. In the first HypHI experiment (Phase 0) planned in 2009, the feasibility of precise hypernuclear spectroscopy with heavy ion beams will be demonstrated by observing π- decay channels of $_\Lambda ^3 {\rm{H}}$, $_\Lambda ^4 {\rm{H}}$ and $_\Lambda ^5 {\rm{He}}$ with 6Li projectiles at 2 A GeV impinging on a 12C target. An overview of the HypHI project and the details of the Phase 0 experiment will be discussed. [ABSTRACT FROM AUTHOR]

A RHBD high performance cache fabricated on 90 nm bulk CMOS is presented. Test silicon cache data arrays can read and write at 1.02 GHz. Irradiation to 2 Mrad(Si) negligibly impacts standby current. The cache is write-through, and relies on error checking to allow cache invalidation when single event upsets or potential single event transients are detected. The write-through cache architectural state will then naturally be reloaded by the ensuing microprocessor operations. Single cycle invalidation is supported. Single event error ion beam test results are presented, as is a description of measured single event effects in array and peripheral circuits and their mitigation by the design. [ABSTRACT FROM PUBLISHER]

Abstract: Extreme states of matter such as Warm Dense Matter “WDM” and Dense Strongly Coupled Plasmas “DSCP” play a key role in many high energy density experiments, however, creating WDM and DSCP in a manner that can be quantified is not readily feasible. In this paper, isochoric heating of matter by intense heavy ion beams in spherical symmetry is investigated for WDM and DSCP research: the heating times are long (100ns), the samples are macroscopically large (millimeter-size) and the symmetry is advantageous for diagnostic purposes. A dynamic confinement scheme in spherical symmetry is proposed which allows even ion beam heating times that are long on the hydrodynamic time scale of the target response. A particular selection of low-Z target tamper and X-ray probe radiation parameters allows to identify the X-ray scattering from the target material and use it for independent charge state measurements Z* of the material under study. [Copyright &y& Elsevier]

We review some novel developments of the electrostatic plasma lens and some new plasma devices based on the plasma-optical idea of magnetic insulation of electrons and equipotentialization along magnetic field lines. The plasma lens configuration of crossed electric and magnetic fields provides an attractive and simple method in establishing a stable plasma discharge at low pressure and has been used to develop some cost-effective low-maintenance plasma devices for ion cleaning, surface activation, and polishing of substrates prior to film deposition. Recent embodiments of these devices use permanent magnets and possess considerable flexibility with respect to spatial configuration. [ABSTRACT FROM AUTHOR]

Abstract: During the past two years, significant experimental and theoretical progress has been made in the US heavy ion fusion science program in longitudinal beam compression, ion-beam-driven warm dense matter, beam acceleration, high brightness beam transport, and advanced theory and numerical simulations. Innovations in longitudinal compression of intense ion beams by propagating through background plasma enable initial beam target experiments in warm dense matter to begin within the next two years. We are assessing how these new techniques might apply to heavy ion fusion drivers for inertial fusion energy. [Copyright &y& Elsevier]

The thermodynamic response of matter heated with intense ion beams was analyzed using the schlieren technique. The energy deposition zone and the propagation of the thermal wave were visualized in the experiment. Fused quartz has been chosen as a target to investigate the phenomena in a material with high yield point. The temperature in the ion beam heated region was estimated using the schlieren data and by analysis of the material changes after irradiation. [ABSTRACT FROM AUTHOR]

At the Physikalisch-Technische Bundesanstalt, an experiment for the direct measurement of the atomic mass unit is underway by accumulating ions from an ion beam up to a weighable mass. Until now, an intense bismuth ion beam of &ap; S mA can be extracted out of a cold or hot reflex discharge ion source (CHORDIS). Different arrangements of the beamline ensuring a high transmission will be discussed. Finally, suitable geometries of anion collector are shown based on SIMION-3D simulations. [ABSTRACT FROM AUTHOR]

We describe applications of the electrostatic plasma lens for manipulating and focusing moderate-energy, high-current, broad, heavy ion beams. Use of a plasma lens in this way has been successfully demonstrated in a series of experiments carried out collaboratively between the Institute of Physics, National Academy of Sciences, Kiev, Ukraine, and the Lawrence Berkeley National Laboratory, Berkeley, CA, in recent years. Mere, we briefly review the plasma lens fundamentals, peculiarities of focusing heavy ion beams, and summarize some recent developments (experiments, computer simulations, theory). We show that there is a very narrow range of low magnetic field for which the optical properties of the lens improve markedly. This opens up some attractive possibilities for the development of a new-generation compact lens based on permanent magnets. Preliminary experimental results obtained at Kiev and Berkeley on the operation of a permanent magnet plasma lens for manipulating wide aperture high-current heavy ion beams are presented and summarized. [ABSTRACT FROM AUTHOR]

Single-event upset effects from heavy ions are measured for Motorola and IBM silicon-on-insulator (Sol) microprocessors with different feature sizes and core voltages. Multiple-bit upsets in registers and D-cache were measured and compared with single-bit upsets. Also, the scaling of the cross section with reduction of feature size for SOI microprocessors is discussed. [ABSTRACT FROM AUTHOR]

Abstract: This contribution is focused on the detailed description of the energy transfer of heavy ions to matter. The experiments were performed at the HIMAC facility in Japan in cooperation with NIRS staff. We employed measuring instruments that have been already been proven in this application; we believe that our specific combination of passive and active detectors is advantageous. Our experimental setup includes track-etched detectors (TED), thermoluminescence dosimeters (TLD), and Liulin, a spectrometer that measures energy deposition in silicon. [ABSTRACT FROM AUTHOR]

Abstract: The contribution describes the methodology of linear energy transfer (LET) spectrometry based on the chemically etched track detectors and results of some experimental studies. Three types of polyallyldiglycolcarbonate (PADC) material have been used in our laboratory: Page—with a thickness of 0.5mm and Tastrak with thicknesses of 0.5 and 1mm. This LET spectrometer is able to detect charged particles with LET above the registration threshold (around , depending on the used material), both primary and secondary, created through nuclear interactions in the detector itself or in the surroundings. During several years the detectors were irradiated by various particles with LET in water up to about . In these studies, primary heavy ions had LET above the registration threshold and so they can be directly detected. However, also some fragments and products of nuclear reactions of the primary particles are registered in the detector, especially behind various absorbers. LET spectrometer calibration curves and also the importance of secondary particles in heavy ion beams and their contribution to the absorbed dose are presented and discussed. [Copyright &y& Elsevier]

Purpose: KHIMA (Korea Heavy Ion Medical Accelerator) project has a plan to develop and construct a research beam line for carbon beam active scanning system. The carbon beam line consists with scanning magnet, beam-monitoring system, energy modulation system. In this study, the significant components, scanning magnets and ridge filter, were designed for the carbon beam active scanning beam line., Methods: The designed scanning magnet and ridge filter were used for 3 dimensional active beam dose delivery simulation by Geant4 Monte Carlo code. The target volume of the active scanning was 10 × 10 × 5 cm 2 on the water phantom with 400 MeV/u of carbon beam. The transvers plane on the target was scanned by 3mm of step size. And, the optimized weighting factors of transverse scanning were obtained by MINUIT fitting package of ROOT. An aluminum ridge filter was designed to generate 5 cm of physical SOBP through step shape, which was optimized through in-house iteration method and the MINUIT package.The simulation was performed with Geant4 through applying the transverse scanning with the obtained weighting factor and the designed ridge filter., Results: The uniformity on the transverse plan will be expected below 4% when it considered scattered beam. Also, the uniformity for longitudinal plane will be expected lower then 5%., Conclusions: This preliminary computational study was shown a possibility of using ridge filter for acceptable 3 dimensional uniformity on active beam delivery system in carbon beam therapy line. The optimization process to reach an acceptable uniformity on clinical use should be followed. In addition, it would be used for the design of treatment planning system software for KIHMA project., (© 2012 American Association of Physicists in Medicine.)