From heavy ions to exotic atoms

OpenAIRE

Indelicato, Paul; Trassinelli, Martino

2005-01-01

We review a number of experiments and theoretical calculations on heavy ions and exotic atoms, which aim at providing informations on fundamental interactions. Among those are propositions of experiments for parity violation measurements in heavy ions and high-precision mesurements of He-like transition energies in highly charged ions. We also describe recent experiments on pionic atoms, that make use of highly-charged ion transitions to obtain accurate measurements of strong interaction shif...

Nuclear research with heavy ions. Annual progress report, January 1, 1977--December 31, 1977

International Nuclear Information System (INIS)

Kaplan, M.

1977-10-01

The experimental research program consists of several interrelated parts: (1) Reactions of Very Heavy Ions with Complex Nuclei; (2) Studies of Compound Nucleus Reactions Induced by Heavy Ions; and (3) Recoil Studies of Heavy Ion Reactions. Using solid-state detector telescopes and gas-ionization detector telescopes we have studied the emission of 1 H, 2 H, 3 H, 4 He and heavy fragments from the reactions of 720 MeV 86 Kr with 197 Au. Coincidence measurements between light charged particles and a heavy fragment indicate that most of the observed 4 He particles are evaporated by equilibrated Kr*-like and Au*-like excited products from deep inelastic reactions, but a significant number of preequilibrium 4 He particles seem to be emitted in directions normal to the separating fragments. Studies of angular correlations between two heavy fragments provide strong evidence for sequential fission of the Au*-like reaction fragments, and the probability of this process has been estimated as a function of Q, the energy damping in the primary collision. Parallel studies of charged particle emission, fission, and evaporation residues in compound nucleus reactions map out the de-excitation characteristics of highly excited heavy nuclei as functions of E* and J. Results are presented for the compound nucleus 194 Hg formed at matched excitation energies via different entrance channels

Classical simulations of heavy-ion fusion reactions and weakly

Indian Academy of Sciences (India)

2014-04-30

Apr 30, 2014 ... Heavy-ion collision simulations in various classical models are discussed. ... are also simulated in a 3-stage classical molecular dynamics (3S-CMD) ... considered as a weakly-bound cluster of deuteron and 4He nuclei, thus, ...

Heavy ion induced mutation in arabidopsis

Energy Technology Data Exchange (ETDEWEB)

Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1997-03-01

Heavy ions, He, C, Ar and Ne were irradiated to the seeds of Arabidopsis thaliana for inducing the new mutants. In the irradiated generation (M{sub 1}), germination and survival rate were observed to estimate the relative biological effectiveness in relation to the LET including the inactivation cross section. Mutation frequencies were compared by using three kinds of genetic loci after irradiation with C ions and electrons. Several interesting new mutants were selected in the selfed progenies of heavy ion irradiated seeds. (author)

Fragmentation and lateral scattering of 120 and 200 MeV/u {sup 4}He ions in water targets

Energy Technology Data Exchange (ETDEWEB)

Rovituso, Marta

2016-06-02

Along with an increased popularity of heavy ions in cancer therapy, {sup 4}He ions have regained the interest of the medical community as a compromise between protons and {sup 12}C ions. Although 2054 patients have been treated with {sup 4}He beams at Lawrence Berkeley Laboratory (LBL) (Berkeley CA, US) between 1975 and 1992, a comprehensive database of biological and physics measurements in the therapeutic energy range is still missing. One of the first steps necessary for introducing {sup 4}He ions in particle therapy, is the development of a dedicated treatment planning system, for which basic physics information such as the characterization of the beam lateral scattering and fragmentation cross sections describing the loss of primary particles and the build up of secondary fragments are required. Examination of data found in the literature reveals a gap in the therapeutic energy range. These measurements are essential for benchmarking not only the new model developed for the in-house treatment planning code TRiP98 (Treatment Planning for Particles), but also for already existing beam algorithms and for Monte Carlo codes like Geant4 and Fluka. The aim of this work is to provide fragmentation cross sections of {sup 4}He ions in the therapeutic energy range. The experimental data presented here were measured at Heidelberg Ion Beam Therapy Center (HIT) (Heidelberg, Germany) using 120 MeV/u and 200 MeV/u {sup 4}He beams. The attenuation of 200 MeV/u {sup 4}He beam in water was studied together with the build up of the secondary fragments produced by nuclear fragmentation processes. Target thicknesses between 1 and 25 cm H{sub 2}O were chosen to investigate nuclear fragmentation also beyond the maximum penetration depth of the {sup 4}He ions. The mixed radiation field produced by the interaction of 120 and 200 {sup 4}He ions with water targets (4.28 and 13.96 cm thick, respectively) has also been investigated in this work by measuring double differential cross

Simulation studies of acceleration of heavy ions and their elemental compositions

International Nuclear Information System (INIS)

Toida, Mieko; Ohsawa, Yukiharu

1996-07-01

By using a one-dimensional, electromagnetic particle simulation code with full ion and electron dynamics, we have studied the acceleration of heavy ions by a nonlinear magnetosonic wave in a multi-ion-species plasma. First, we describe the mechanism of heavy ion acceleration by magnetosonic waves. We then investigate this by particle simulations. The simulation plasma contains four ion species: H, He, O, and Fe. The number density of He is taken to be 10% of that of H, and those of O and Fe are much lower. Simulations confirm that, as in a single-ion-species plasma, some of the hydrogens can be accelerated by the longitudinal electric field formed in the wave. Furthermore, they show that magnetosonic waves can accelerate all the particles of all the heavy species (He, O, and Fe) by a different mechanism, i.e., by the transverse electric field. The maximum speeds of the heavy species are about the same, of the order of the wave propagation speed. These are in good agreement with theoretical prediction. These results indicate that, if high-energy ions are produced in the solar corona through these mechanisms, the elemental compositions of these heavy ions can be similar to that of the background plasma, i.e., the corona

Nuclear interactions in high energy heavy ions and applications in astrophysics

International Nuclear Information System (INIS)

Wefel, J.P.; Guzik, T.G.

1993-01-01

The overall objective is to study the mechanisms and the energy dependence of heavy ion fragmentation by studying the reactions of heavy ion projectiles (e.g. 4 He, 16 O, 20 Ne, 28 Si, 56 Fe) in a variety of targets (H, He, C, Si, Cu, Pb) and at a number of beam energies exceeding 0.1 GeV/nucleon. The results have application to questions in high-energy nuclear astrophysics. Most of the discussion is on low-energy 16 O, 28 Si data analysis. The description includes analysis procedures and techniques, detector calibrations, data selections and normalizations. Cross section results for the analysis are also presented. 83 figs., 6 tabs., 73 refs

Observation of the Antimatter Nuclei in Relativistic Heavy Ion Collisions

International Nuclear Information System (INIS)

Yoo, I.-K.

2013-01-01

Recently antimatter hyper-triton nuclei ( 3 Λ¯ H ¯) and antimatter helium nuclei ( 4 2 He ¯ ) are discovered with the Solenoidal Tracker At RHIC detector in relativistic heavy ion collisions at Relativistic Heavy Ion Collider (RHIC) (STAR Collaboration in Science 328(5974):58-62, 2010; STAR Collaboration in Nature 473:353-356, 2011). In this presentation, discoveries of antimatter particle are historically scanned and the recent observations at RHIC are reported in details as well as potential possibilities of discovery of antimatter nuclei at ALICE. (author)

He2+ molecular ion and the He- atomic ion in strong magnetic fields

Science.gov (United States)

Vieyra, J. C. Lopez; Turbiner, A. V.

2017-08-01

We study the question of existence, i.e., stability with respect to dissociation of the spin-quartet permutation- and reflection-symmetric 4(-3) +g (Sz=-3 /2 ,M =-3 ) state of the (α α e e e ) Coulomb system: the He2 + molecular ion, placed in a magnetic field 0 ≤B ≤10 000 a.u. We assume that the α particles are infinitely massive (Born-Oppenheimer approximation of zero order) and adopt the parallel configuration, when the molecular axis and the magnetic field direction coincide, as the optimal configuration. The study of the stability is performed variationally with a physically adequate trial function. To achieve this goal, we explore several helium-containing compounds in strong magnetic fields, in particular; we study the spin-quartet ground state of the He- ion and the ground (spin-triplet) state of the helium atom, both for a magnetic field in 100 ≤B ≤10 000 a.u. The main result is that the He2 + molecular ion in the state 4(-3) +g is stable towards all possible decay modes for magnetic fields B ≳120 a .u . and with the magnetic field increase the ion becomes more tightly bound and compact with a cigar-type form of electronic cloud. At B =1000 a .u . , the dissociation energy of He2 + into He-+α is ˜702 eV and the dissociation energy for the decay channel to He +α +e is ˜729 eV , and both energies are in the energy window for one of the observed absorption features of the isolated neutron star 1E1207.4-5209.

Structure of very heavy few-electron ions - new results from the heavy ion storage ring, ESR

International Nuclear Information System (INIS)

Mokler, P.H.; Stoehlker, T.; Kozhuharov, C.; Moshammer, R.; Rymuza, P.; Bosch, F.; Kandler, T.

1993-08-01

The heavy ion synchrotron/storage ring facility at GSI, SIS/ESR, provides intense beams of cooled, highly-charged ions up to naked uranium (U 92+ ). By electron capture during ion-atom collisions in the gas target of the ESR or by recombination at ion-electron encounters in the ''electron cooler'' excited states are populated. The detailed structure of very heavy one-, two- and three-electron ions is studied. The different mechanisms leading to the excited states are described, as well as the new experimental tools now available for a detailed spectroscopy of these interesting systems. Special emphasis is given to X-ray transitions to the groundstates in H- and He-like systems. For the heaviest species the groundstate Lambshift can now be probed on an accuracy level of better than 10% using solid-state X-ray detectors. Applying dispersive X-ray analyzing techniques, this accuracy will certainly be improved in future. However, utilizing the dielectronic resonances for a spectroscopy, the structure in Li-like heavy ions can already be probed now on the sub eV level. (orig.)

Sputtering of solid deuterium by He-ions

DEFF Research Database (Denmark)

Schou, Jørgen; Stenum, B.; Pedrys, R.

2001-01-01

Sputtering of solid deuterium by bombardment of 3He+ and 4He+ ions was studied. Some features are similar to hydrogen ion bombardment of solid deuterium, but for the He-ions a significant contribution of elastic processes to the total yield can be identified. The thin-film enhancement is more pro...... pronounced than that for hydrogen projectiles in the same energy range....

M-shell ionization of heavy elements by 0.1-1.0 MeV/amu 1,2H and 3,4He ions

International Nuclear Information System (INIS)

Pajek, M.; Banas, D.; Braziewicz, J.; Czarnota, M.; Bienkowski, A.; Jaskola, M.; Korman, A.; Trautmann, D.; Lapicki, G.

2006-01-01

The M-shell ionization in high-Z atoms by low-energy light 1 1 H, 1 2 H, 2 3 He, and 2 4 He ions have been studied systematically in the energy range 0.1-1.0 MeV/amu in order to verify the available theoretical approaches describing the M-shell ionization by charged particles in asymmetric collisions. The present low-energy data, combined with our earlier results reported for M-shell ionization by hydrogen and helium ions for higher energies, form a systematic experimental basis to test the theoretical predictions of M-shell ionization based on the plane-wave Born approximation (PWBA), the semiclassical approximation (SCA), and the binary-encounter approximation (BEA). In the PWBA based approaches the energy loss (E), Coulomb deflection (C), perturbed stationary state (PSS), and relativistic (R) effects were considered within the ECPSSR theory and its recent modification, called the ECUSAR theory, in which a description of the PSS effect was corrected to account for the united- and separated-atom (USA) electron binding energy limits. In the SCA calculations with relativistic wave functions the binding effect was included only in the limiting cases of separated-atom and united-atom limits. Possible contribution of the electron capture, multiple ionization, and recoil ionization to the M-shell vacancy production, which is dominated for light ions impact by direct single ionization process, are also discussed. The universal scaling of measured M-shell x-ray production and ionization cross sections was investigated in detail. Using the present data the isotopic effect has been studied by comparing the measured M-shell ionization cross-section ratios for equal-velocity hydrogen 1 1 H and 1 2 H as well as helium 2 3 He and 2 4 He isotopes. In addition, the ratios of measured ionization cross sections for 1 2 H and 2 4 He were used to investigate the role of the binding effect. The present results are of practical importance for the application of particle-induced x

The nucleation of vorticity by ions in superfluid 4He

International Nuclear Information System (INIS)

Muirhead, C.M.; Vinen, W.F.; Donnelly, R.J.

1985-01-01

The theory developed in Part I is extended to include a discussion of nucleation by negative ions in the presence of dissolved 3 He at a concentration such that at a low temperature the negative ion bubble is likely to have adsorbed on its surface either one or two 3 He atoms. It is argued that the adsorbed 3 He atom can change the nucleation rate for two reasons: the atom can modify the perturbation applied to the helium at the surface of the ions; and it can act as a source of energy. The second of these effects is explored in some detail. It is shown that the 3 He atom is probably less strongly bound to the ion than it would be to the core of a vortex line; furthermore the atom adsorbed onto the surface of the ion can exist in a number of excited states (Shikin states), which are thermally populated even at quite low temperatures. Therefore, when nucleation of a vortex takes place, the 3 He atom might move from the ion surface to the core of the vortex or simply from one Shikin state to another of lower energy; in either case there is a release of energy. The existence of this energy release means, first, that nucleation becomes energetically possible at a reduced ionic velocity and secondly, that the energy barrier opposing nucleation is reduced in size. Therefore the critical velocity for vortex nucleation is reduced, and, for a given supercritical velocity, the rate of nucleation is increased. Addition of a second 3 He atom would have a similar effect. Further experiments are required to check the detailed predictions of the theory. (author)

Calorimetric low temperature detectors for heavy ion physics

Energy Technology Data Exchange (ETDEWEB)

Egelhof, P.; Kraft-Bermuth, S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Mainz Univ. (Germany). Inst. fuer Physik

2005-05-01

Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics at present and at the next generation heavy ion facilities is given with a special emphasis on the conditions for heavy ion detection and the potential advantage of cryogenic detectors for applications in heavy ion physics. Two types of calorimetric low temperature detectors for the detection of energetic heavy ions have been developed and their response to the impact of heavy ions was investigated systematically for a wide range of energies (E=0.1-360 MeV/amu) and ion species ({sup 4}He.. {sup 238}U). Excellent results with respect to energy resolution, {delta}E/E ranging from 1 to 5 x 10{sup -3} even for the heaviest ions, and other basic detector properties such as energy linearity with no indication of a pulse height defect, energy threshold, detection efficiency and radiation hardness have been obtained, representing a considerable improvement as compared to conventional heavy ion detectors based on ionization. With the achieved performance, calorimetric low temperature detectors bear a large potential for applications in various fields of basic and applied heavy ion research. A brief overview of a few prominent examples, such as high resolution nuclear spectroscopy, high resolution nuclear mass determination, which may be favourably used for identification of superheavy elements or in direct reaction experiments with radioactive beams, as well as background discrimination in accelerator mass spectrometry, is given, and first results are presented. For instance, the use of cryogenic detectors allowed to improve the sensitivity in trace analysis of {sup 236}U by one order of magnitude and to determine the up to date smallest isotope ratio of {sup 236}U/{sup 238}U = 6.1 x 10{sup -12} in a sample of natural uranium. Besides the detection of heavy ions, the concept of cryogenic detectors also

Calorimetric low temperature detectors for heavy ion physics

International Nuclear Information System (INIS)

Egelhof, P.; Kraft-Bermuth, S.; Mainz Univ.

2005-07-01

Calorimetric low temperature detectors have the potential to become powerful tools for applications in many fields of heavy ion physics. A brief overview of heavy ion physics at present and at the next generation heavy ion facilities is given with a special emphasis on the conditions for heavy ion detection and the potential advantage of cryogenic detectors for applications in heavy ion physics. Two types of calorimetric low temperature detectors for the detection of energetic heavy ions have been developed and their response to the impact of heavy ions was investigated systematically for a wide range of energies (E=0.1-360 MeV/amu) and ion species ( 4 He.. 238 U). Excellent results with respect to energy resolution, ΔE/E ranging from 1 to 5 x 10 -3 even for the heaviest ions, and other basic detector properties such as energy linearity with no indication of a pulse height defect, energy threshold, detection efficiency and radiation hardness have been obtained, representing a considerable improvement as compared to conventional heavy ion detectors based on ionization. With the achieved performance, calorimetric low temperature detectors bear a large potential for applications in various fields of basic and applied heavy ion research. A brief overview of a few prominent examples, such as high resolution nuclear spectroscopy, high resolution nuclear mass determination, which may be favourably used for identification of superheavy elements or in direct reaction experiments with radioactive beams, as well as background discrimination in accelerator mass spectrometry, is given, and first results are presented. For instance, the use of cryogenic detectors allowed to improve the sensitivity in trace analysis of 236 U by one order of magnitude and to determine the up to date smallest isotope ratio of 236 U/ 238 U = 6.1 x 10 -12 in a sample of natural uranium. Besides the detection of heavy ions, the concept of cryogenic detectors also provides considerable advantage for X

One- and two-electron processes in collisions of heavy ions with H2 and He

International Nuclear Information System (INIS)

Richard, P.; Hall, J.; Shinpaugh, J.L.; Sanders, J.M.; Tipping, T.N.; Zouros, T.J.M.; Lee, D.H.; Schmidt-Boecking, H.

1987-01-01

In this paper we present a description of the apparatus and results for experiments involving one- and two-electron processes in collisions of heavy ions with H 2 and He. The experiments were performed using one-electron and bare projectiles. In the first section we describe the measurement of pure ionization of one-electron projectiles by H 2 targets and compare with previous results for He targets. We also present the results for one-electron capture by the projectile from H 2 targets. The energy dependence of the cross sections is compared to theoretical predictions for atomic and molecular hydrogen targets. Both experiments were performed by measuring only the final charge state of the projectile. In the second section we describe the measurement of partial cross sections for the same collisions by measuring the target recoil charge state in coincidence with the projectile charge state. By this method we can measure pure single- and double-ionization of the target, pure single-electron transfer and transfer ionization, and pure double-electron transfer. This experiment is presently being performed for bare flourine on He; however, absolute cross sections are not available at the time of this conference. (orig.)

Effect of heavy ion irradiation on sucrose radical production

International Nuclear Information System (INIS)

Nakagawa, Kouichi; Sato, Yukio

2004-01-01

We investigated sucrose radicals produced by heavy-ion irradiation with various LETs (linear energy transfer) and the possibility for a sucrose ESR (electron spin resonance) dosimeter. The obtained spectral pattern was the same as that for helium (He) ions, carbon (C) ions, neon (Ne) ions, argon (Ar) ions, and iron (Fe) ions. Identical spectra were measured after one year, but the initial intensities decreased by a few percent when the samples were kept in ESR tubes with the caps at ambient temperature. The total spin concentration obtained by heavy-ion irradiation had a linear relation with the absorbed dose, and correlated logarithmically with the LET. Qualitative ESR analyses showed that the production of sucrose radicals depended on both the particle identity and the LET at the same dose. The production of spin concentration by He ions was the most sensitive to LET. Empirical relations between the LET and the spin yield for various particles imply that the LET at a certain dose can be estimated by the spin concentration. (authors)

Heavy-ion radiography and heavy-ion computed tomography

International Nuclear Information System (INIS)

Fabrikant, J.I.; Holley, W.R.; McFarland, E.W.; Tobias, C.a.

1982-02-01

Heavy-ion projection and CT radiography is being developed into a safe, low-dose, noninvasive radiological procedure that can quantitate and image small density differences in human tissues. The applications to heavy-ion mammography and heavy-ion CT imaging of the brain in clinical patients suggest their potential value in cancer diagnosis

Heavy-ion induced desorption yields of amorphous carbon films bombarded with 4.2 MeV/u lead ions

CERN Document Server

Mahner, E; Küchler, D; Scrivens, R; Costa Pinto, P; Yin Vallgren, C; Bender, M

2011-01-01

During the past decade, intense experimental studies on the heavy-ion induced molecular desorption were performed in several particle accelerator laboratories worldwide in order to understand and overcome large dynamic pressure rises caused by lost beam ions. Different target materials and various coatings were studied for desorption and mitigation techniques were applied to heavy-ion accelerators. For the upgrade of the CERN injector complex, a coating of the Super Proton Synchrotron (SPS) vacuum system with a thin film of amorphous carbon is under study to mitigate the electron cloud effect observed during SPS operation with the nominal proton beam for the Large Hadron Collider (LHC). Since the SPS is also part of the heavy-ion injector chain for LHC, dynamic vacuum studies of amorphous carbon films are important to determine their ion induced desorption yields. At the CERN Heavy Ion Accelerator (LINAC 3), carbon-coated accelerator-type stainless steel vacuum chambers were tested for desorption using 4.2 Me...

Energetic heavy ions overcome tumor radioresistance caused by overexpression of Bcl-2

International Nuclear Information System (INIS)

Hamada, Nobuyuki; Hara, Takamitsu; Omura-Minamisawa, Motoko; Funayama, Tomoo; Sakashita, Tetsuya; Sora, Sakura; Yokota, Yuichiro; Nakano, Takashi

2008-01-01

Background and purpose: Overexpression of Bcl-2 is frequent in human cancers and has been associated with radioresistance. Here we investigated the potential impact of heavy ions on Bcl-2 overexpressing tumors. Materials and methods: Bcl-2 cells (Bcl-2 overexpressing HeLa cells) and Neo cells (neomycin resistant gene-expressing HeLa cells) exposed to γ-rays or heavy ions were assessed for the clonogenic survival, apoptosis and cell cycle distribution. Results: Whereas Bcl-2 cells were more resistant to γ-rays (0.2 keV/μm) and helium ions (16.2 keV/μm) than Neo cells, heavy ions (76.3-1610 keV/μm) yielded similar survival regardless of Bcl-2 overexpression. Carbon ions (108 keV/μm) decreased the difference in the apoptotic incidence between Bcl-2 and Neo cells, and prolonged G 2 /M arrest that occurred more extensively in Bcl-2 cells than in Neo cells. Conclusions: High-LET heavy ions overcome tumor radioresistance caused by Bcl-2 overexpression, which may be explained at least in part by the enhanced apoptotic response and prolonged G 2 /M arrest. Thus, heavy-ion therapy may be a promising modality for Bcl-2 overexpressing radioresistant tumors

High-energy elastic recoil detection heavy ions for light element analysis

International Nuclear Information System (INIS)

Goppelt-Langer, P.; Yamamoto, S.; Takeshita, H.; Aoki, Y.; Naramoto, H.

1994-01-01

The detection of light and medium heavy elements in not homogeneous solids is a severe problem in ion beam analysis. Heavy elements can be detected by the well established Rutherford backscattering technique (RBS). In a homogeneous host material most impurities can be easily analyzed by secondary ion mass spectroscopy (SIMS). Some isotopes ( 3 He, 6 Li, 10 B) can be measured by nuclear reaction analysis (NRA) using thermal neutrons inducing (n, p) or (n, α) reactions. Others can be detected by energetic ion beams by nuclear reactions (e.g. 15 N( 1 H, αγ) 12 C for analysis of hydrogen). A high content of H, D or T can be also determined by elastic recoil detection using an energetic He beam. The latter technique has been developed to a universal method for detection of light and heavy elements in any target, using a high energetic heavy ion beam and a detector system, which is able to identify the recoils and delivers energy and position of the particles. (author)

Acceleration of heavy-ion beams at the SF cyclotron

International Nuclear Information System (INIS)

Sakurada, Yuzo; Yamazaki, Tsutomu.

1984-10-01

With the development of the new arc-heated cathode PIG type source, heavy-ion acceleration in the SF cyclotron has been drastically augmented, which means that a stable routine operation is being realized as well as the number of ion species is increasing. Excellent performance is also being exhibited with the arc power supply and gas feeding system required for the operation of the heavy-ion source. At present, the gaseous ions which are being accelerated are as follows: He, B, C, N, O, F, Ne, S, Ar and Xe. In the meantime, the metallic ions which are being accelerated likewise are Li, Be, Na, Mg, Al, Si, Cl, Ca, Ti, Fe and Cu. In this paper, results of mainly the research of heavy-ion acceleration conducted during the period from 1983 to July 1984 are described. (author)

Heavy-ion radiography

International Nuclear Information System (INIS)

Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.; Woodruff, K.H.; MacFarland, E.W.

1983-01-01

High energy, heavy-ion beams offer superior discrimination of tissue electron densities at very low radiation doses. This characteristic has potential for diagnostic medical imaging of neoplasms arising in the soft tissues and organs because it can detect smaller inhomogeneities than x rays. Heavy-ion imaging may also increase the accuracy of cancer radiotherapy planning involving use of accelerated charged particles. In the current physics research program of passive heavy-ion imaging, critical modulation transfer function tests are being carried out in heavy-ion projection radiography and heavy-ion computerized tomography. The research goal is to improve the heavy-ion imaging method until it reaches the limits of its theoretical resolution defined by range straggling, multiple scattering, and other factors involved in the beam quality characteristics. Clinical uses of the imaging method include the application of heavy-ion computerized tomography to heavy-ion radiotherapy planning, to the study of brain tumors and other structures of the head, and to low-dose heavy-ion projection mammography, particularly for women with dense breasts where other methods of diagnosis fail. The ions used are primarily 300 to 570 MeV/amu carbon and neon ions accelerated at the Lawrence Berkeley Laboratory Bevalac

Mobilities of ions trapped on vortex lines in dilute 3He--4He solutions

International Nuclear Information System (INIS)

Huang, W.; Dahm, A.J.

1976-01-01

A model calculation of the mobility of a positive ion in the presence of 3 He atoms condensed on a vortex core is presented. Reasonable qualitative and quantitative agreement between theory and experiment is obtained, and reasons for differences are discussed. A reason for the larger mobility of the negative ion in comparison to the smaller positive ion is suggested. The contribution of vortex waves to the scattering of ions is addressed

Heavy ion measurements by use of chemical detectors

International Nuclear Information System (INIS)

Huebner, K.; Erzgraeber, G.; Eichhorn, K.

1980-01-01

In order to test whether the threshold system polyvinyl alcohol/methyl organe/chloral hydrate/sodium tetraborate permits quantitative detection of individual particles, the chemical detector was irradiated at the JINR U-200 cyclotron with 4 He, 12 C, 18 O, 22 Ne ions having different LET. Irradiations were performed with detectors of four different borax concentrations (the chloral hydrate concentration being constant). The colour change dose Dsub(u) increases linearly with increasing borax concentration and at constant borax concentration with increasing LET. Hence it follows that the G value of dehydrochlorination decreases with increasing LET. Fluence ranges measurable with detectors of different composition are given for the heavy ions studied. (author)

Heavy Ion Fusion Accelerator Research (HIFAR)

International Nuclear Information System (INIS)

1991-04-01

This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C s + sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac

Heavy-ion induced desorption yields of cryogenic surfaces bombarded with 4.2 MeV/u lead ions

CERN Document Server

Mahner, E; Evans, L; Kollmus, H; Küchler, D; Scrivens, R; Severin, D; Wengenroth, M; CERN. Geneva. ATS Department

2011-01-01

The ion-induced desorption experiment, installed in the CERN Heavy-Ion Accelerator LINAC 3, has been used to study the dynamic outgassing of cryogenic surfaces. Two different targets, bare and goldcoated copper, were bombarded under perpendicular impact with 4.2 MeV/u Pb54+ ions. Partial pressure rises of H2, CH4, CO, and CO2 and effective desorption yields were measured at 300, 77, and 6.3 K using single shot and continuous ion bombardment techniques. We find that the heavy-ion-induced desorption yield is temperature dependent and investigate the influence of CO gas cryosorbed at 6.3 K. The gain in desorption yield reduction at cryogenic temperature vanishes after several monolayers of CO are cryosorbed on both targets. In this paper we describe the new cryogenic target assembly, the temperature-dependent pressure rise, desorption yield, and gas adsorption measurements.

Heavy Flavor Production in Heavy Ion Collisions at CMS

CERN Document Server

Sun, Jian

2016-01-01

Studies of Heavy flavor production are of great interest in heavy ion collisions. In the produced medium, the binding potential between a quark and antiquark in quarkonium is screened by surrounding light quarks and antiquarks. Thus, the various quarkonium states are expected to be melt at different temperatures depending on their binding energies, which allows us to characterize the QCD phase transition. In addition, open heavy flavor production are relevant for flavor-dependence of the in-medium parton energy loss. In QCD, gluons are expected to lose more energy compared to quarks when passing through the QGP due to the larger color charge. Compared to light quarks, heavy quarks are expected to lose less radiative energy because gluon radiation is suppressed at angles smaller than the ratio of the quark mass to its energy. This dead cone effect (and its disappearance at high transverse momentum) can be studied using open heavy flavor mesons and heavy flavor tagged jets. With CMS detector, quarkonia, open he...

RHIC heavy ion operations performance

CERN Document Server

Satogata, T; Ferrone, R; Pilat, F

2006-01-01

The Relativistic Heavy Ion Collider (RHIC) completed its fifth year of operation in 2005, colliding copper ion beams with ps=200 GeV/u and 62.4 GeV/u[1]. Previous heavy ion runs have collided gold ions at ps=130 GeV/u, 200 GeV/u, and 62.4 GeV/u[2], and deuterons and gold ions at ps=200 GeV/u[3]. This paper discusses operational performance statistics of this facility, including Cu- Cu delivered luminosity, availability, calendar time spent in physics stores, and time between physics stores. We summarize the major factors affecting operations efficiency, and characterize machine activities between physics stores.

Heavy ion program at BNL: AGS, RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Barton, D.S.

1987-01-01

With the recent commissioning of fixed target, heavy ion physics at the AGS, Brookhaven National Laboratory (BNL) has embarked on a long range program in support of relativistic heavy ion research. Acceleration of low mass heavy ions (up to sulfur) to an energy of about 14.5 GeV/nucleon is possible with the direct connection of the BNL Tandem Van de Graaff and AGS accelerators. When completed, the new booster accelerator will provide heavy ions over the full mass range for injection and subsequent acceleration in the AGS. BNL is now engaged in an active R and D program directed toward the proposed Relativistic Heavy Ion Collider (RHIC). The results of the first operation of the low mass heavy ion program will be reviewed, and future expectations discussed. The expected performance for the heavy ion operation of the booster will be described and finally, the current status and outlook for the RHIC facility will be presented

Simulation and dosimetric analysis of protons, 4He ions and 12C ions beams for brain neoplasm therapy

International Nuclear Information System (INIS)

Santos, Guilherme M.; Mello, Victor Barreto Braga; Mello Neto, Joao R.T. de

2016-01-01

This study aims to simulate protons, 4 He ions and 12 C ions beams, radiating the head of an average-sized man with the purpose of treating a hypothalamic tumor. GEANT4 was used to simulate the head (skin, skull and brain), and the beam, giving their characteristics and also the physical processes involved. The results sought herein are graphs of depth for relative dose for each of the three particles incident on the settings mentioned above. (author)

Damage of niobium surfaces caused by bombardment with 4He+ ions of different energies typical for T-20

International Nuclear Information System (INIS)

Guseva, M.I.; Gusev, V.; Martynenko, Yu.V.; Das, S.K.; Kaminsky, M.

1979-01-01

The aim of the present studies was to study surface damage due to blistering of both annealed and cold-worked niobium (a candidate first wall material for keV) irradiated sequentially with 4 He + ions with energies of 0.5 to 1800 keV for a total dose of 5.0 C/cm 2 . A typical surface of cold-worked Nb after irradiations with 4 He + ions with increasing energy from 0.5 to 90 keV is shown. The blister diameters range from 0.1 μm to 3 μm, and most of the blisters have exfoliated. The blisters fall into several size classes, the two most dominant ones having most probable blister diameters of approx. 0.27 μm and approx. 2.0 μm. The skin thickness of the larger blisters was measured to be approx. 0.23 μm. Also shown is the same area after irradiation with 150-1800-keV 4 He + irradiation for a dose of 0.66 C/cm 2 . A few additional blisters can be seen. A cold-worked Nb surface that was irradiated only with 150-1800-keV 4 He + ions is also shown. It is seen that prior irradiation with 0.5-90-keV 4 He + helped in significantly reducing blistering. For a total dose of 0.5 C/cm 2 , the erosion yield due to helium blistering of Nb ranges from (5.4 +- 2.0) x 10 -3 to (1.5 +- 0.7) x 10 -2 atoms/ion. For the cold-worked Nb target the results indicate clearly that the 4 He + implantations for the energy range from 0.5 to 90 keV help to reduce both the density and diameter of blisters formed by subsequent He-implantation for the energy ranging from 150 to 1800 keV. 2 figures

Formation of planar waveguides in bismuth germanate by 4He+ ion implantation

International Nuclear Information System (INIS)

Mahdavi, S.M.; Chandler, P.J.; Townsend, P.D.

1989-01-01

Planar optical waveguides have been formed in crystalline bismuth germanate (BGO) Bi 4 Ge 3 O 12 , by He + ion implantation. The refractive index profiles have been determined using a dark-mode technique at 0.6328 and 0.488 micrometres. In the region of the electronic and nuclear stopping power of the ion beam in bismuth germanate there is an index enhancement, which forms an optical 'well', This is stable up to ∼ 200 0 C, but then there is a gradual recovery of index up to 400 0 C. Between 425 and 450 0 C, for heavily implanted samples (≥4 x 10 16 ions/cm 2 ), the well rapidly disappears, and is replaced by a sharp 'barrier' of reduced index. For lower dose implants ( 16 ion/cm 2 ) at 450 0 C many of the modes disappear without being replaced by a sharp barrier. (author)

Production of isomers in compound and transfer reactions with 4He ions

International Nuclear Information System (INIS)

Karamyan, S.A.; Aksenov, N.V.; Albin, Yu.A.; Bozhikov, G.A.; Dmitriev, S.N.; Starodub, G.Ya.; Vostokin, G.K.; Carroll, J.J.

2011-01-01

A well-known island of nuclear isomerism appears near A = 175-180 due to the deformation alignment of single-particle orbits at high angular momentum. This sometimes results in the formation of multi-quasiparticle states with record spin that are long-lived because of 'K-hindrance', i.e., symmetry rearrangement. Production methods and spectroscopic studies of these isomers remain a challenge for modern nuclear reaction and nuclear structure physics. Activities were produced by irradiation of 176 Yb(97.6%) enriched and nat Lu targets with 35-MeV 4 He ions from the internal beam of the U200 cyclotron. Induced activities were analyzed applying methods of radiochemistry and gamma spectroscopy. Yields of compound and nucleon-transfer reactions were measured and the isomer-to-ground state ratios were deduced. Calculated results were obtained using standard procedures to reproduce the (α, xn) cross sections, and the systematic behavior of the nucleon-transfer yields was established. The isomer-to-ground state ratios for direct reactions with 4 He ions were examined, resulting in a new characterization of the reaction mechanism

The effect of Demkov coupling in the rotational predissociation of 3He4He+, ch. 4

International Nuclear Information System (INIS)

Asselt, N.P.F.B. van; Maas, J.G.; Los, J.

1976-01-01

The momentum distribution of the 3 He + and the 4 He + fragments, both originating from rotational predissociation of 3 He 4 He + has been measured. There is a pronounced difference between the intensity distributions in both spectra. This difference is explained as the result of a Demkov coupling between the two lowest electronic states of the molecular ion. The rotational quantum numbers of the states involved are calculated from the spectra

QED corrections to the 4p-4d transition energies of copperlike heavy ions

International Nuclear Information System (INIS)

Chen, M. H.; Cheng, K. T.; Johnson, W. R.; Sapirstein, J.

2006-01-01

Quantum electrodynamic (QED) corrections to 4p-4d transition energies of several copperlike ions with Z=70-92 are calculated nonperturbatively in strong external fields to all orders in binding corrections. Dirac-Kohn-Sham potentials are used to account for screening and core-relaxation effects. For the 4p 1/2 -4d 3/2 transition in copperlike bismuth, thorium, and uranium, results are in good agreement with empirical QED corrections deduced from differences between transition energies obtained from recent high-precision electron-beam ion-trap measurements and those calculated with the relativistic many-body perturbation theory (RMBPT). These comparisons provide sensitive tests of QED corrections for high-angular-momentum states in many-electron heavy ions and illustrate the importance of core-relaxation corrections. Comparisons are also made with other theories and with experiments on the 4s-4p transition energies of high-Z Cu-like ions as accuracy checks of the present RMBPT and QED calculations

Microscopic descriptions of high-energy heavy-ion collisions

International Nuclear Information System (INIS)

Bodmer, A.R.

1977-01-01

The essentials of the equation-of-motion (EOM) approach are given and some of its significant and interesting results are described. A framework for the theoretical description of high-energy heavy-ion (HE-HI) collisions is presented; specifically included are a critical assessment of various approaches--EOM calculations, Boltzmann equations/cascade calculations, and hydrodynamics--their relationships and their respective domains of applicability, if any, to HE-HI collisions. 11 figures, 3 tables

Nuclear research with heavy ions. Annual progress report, January 1, 1981-December 31, 1981

International Nuclear Information System (INIS)

Kaplan, M.

1981-11-01

The experimental research program is primarily concerned with the nuclear reactions induced by collisions between heavy-ion projectiles and complex target nuclei, the dynamics and thermodynamics associated with such collisions, and the relationships of the observables to the equilibrium and non-equilibrium properties of nuclear matter. As a sensitive probe of the nuclear interactions, detailed measurements of light-charged-particle emission were performed using counter telescopes for atomic number and mass number identification. Preliminary results from a new experiment on direct and evaporation-like emission of 4 He from reactions of 340-MeV 40 Ar with 238 U are reported. Using a large two-dimensional position-sensitive avalanche detector, and measuring three-fold coincidence events between two fission fragments and an emitted 4 He particle, we were able to distinguish emission processes in fusion-like fission from those associated with inelastic reactions. Analysis of the data shows isotropic and strongly forward-peaked 4 He components for both fusion and sequential fission, and kinematic evidence indicates substantial evaporation-like emission from the composite system rather than from fission fragments. The effects of light element impurities on charged particle spectra from heavy ion collisions are discussed, and a technique for directly evaluating the impurity contribution is briefly described

Direct harvesting of Helium-3 (3He) from heavy water nuclear reactors

International Nuclear Information System (INIS)

Bentoumi, G.; Didsbury, R.; Jonkmans, G.; Rodrigo, L.; Sur, B.

2013-01-01

The thermal neutron activation of deuterium inside a heavy-water-moderated or -cooled nuclear reactor produces a build-up of tritium in the heavy water. The in situ decay of tritium can, for certain reactor types and operating conditions, produce potentially useable amounts of 3 He, which can be directly extracted via the heavy-water cover gas without first separating, collecting and storing tritium outside the reactor. It is estimated that the amount of 3 He available for recovery from the moderator cover gas of a 700 MWe class Pressurized Heavy Water Reactor (PHWR) ranges from 0.1 to 0.7 m 3 (STP) per annum, varying with the tritium activity buildup in the moderator. The harvesting of 3 He would generate approximately 12.7 m 3 (STP) of 3 He, worth more than $30M at current market rates, over a typical 25-year operating cycle of the PHWR. This paper discusses the production of 3 He in the moderator of a PHWR and its extraction from the 4 He moderator cover gas system using conventional methods. (author)

The breakdown of superfluidity in liquid 4He

International Nuclear Information System (INIS)

Nancolas, G.G.; McClintock, P.V.E.; Bowley, R.M.

1985-01-01

The rate upsilon at which negative ions nucleate charged vortex rings in a series of extremely dilute superfluid 3 He/ 4 He solutions has been measured at a pressure of 23 bar over a temperature range (T) 0.33 - 0.61K, electric field range (E) 1.0 x 10 4 - 1.5 x 10 6 Vm -1 and an isotopic ratio range (x) ( 3 H/ 4 He) = 2.1 x 10 -8 - 1.7 x 10 -7 . The results are presented. A model is proposed which accounts for the behaviour of upsilon(E,T) in terms of changes in the average occupancy by 3 He atoms of trapping states on the surface of the ion if the nucleation rate ν 1 , due to ions each having one trapped 3 He atom, is very much greater than ν 0 for bare ions. The nonlinearities in ν(x 3 ) are interpreted in terms of the simultaneous trapping of two (or more) 3 He atoms on a significant fraction of the ions. The model can be fitted closely to the experimental data, yielding numerical values of ν 1 , of the 3 He binding energy on the ion, and of a number of other relevant quantities. The addition of a 3 He atom to a bare ion affects its propensity to create vortex rings by reducing the critical velocity for the process and by increasing the rate constant. The implications of these results for microscopic theories of the vortex nucleation mechanism are discussed. (U.K.)

The Path to Heavy Ions at LHC and Beyond

Science.gov (United States)

Gutbrod, Hans H.

My appreciation of Rolf Hagedorn motivates me to look back at my more than 40 years of trial and error in relativistic heavy ion physics. More than once, wise colleagues helped me move forward to new and better understandings. Rolf Hagedorn was one of these important people. At first, I met him anonymously in the mid 1970s when reading his 1971 Cargèse Lectures in Physics, and later in person for many years in and around CERN. I wonder what this modest person would say about his impact on physics in this millennium. As he is not here to answer, I and others give our answers in this book. I focus my report on the beginning of the research program with relativistic heavy ions, the move to CERN-SPS and the development of the heavy ion collaboration at the CERN-LHC.

FOBOS - a 4π-fragment spectrometer for heavy-ion reaction products

International Nuclear Information System (INIS)

Ortlepp, H.G.; Schilling, K.D.

1992-06-01

The FOBOS detector presently under construction at Dubna is intended for heavy ion reaction studies in the bombarding energy range of 10...100 AMeV. It will consist of a 'gas-ball' of 30 position-sensitive avalanche counters and 30 axial ionization chambers behind them, a shell of 190 scintillation counters surrounding the gas ball and a forward phoswich array. All charged reaction products may be measured in a wide dynamic range and in a geometry covering a substantial part of 4π. Special developments were necessary concerning the mechanical construction, the detector design, the evacuation and gas supply and the electronics. Presently individual detector modules are being tested at the beam of the U-400 heavy ion cyclotron of the Laboratory of nuclear reactions. (orig.)

Performance of a mass spectrometer for determining low tritium levels from 3He/4He measurements

International Nuclear Information System (INIS)

Lynch, M.C.F.; Kay, D.J.

1981-01-01

The Micromass 3000 mass spectrometer is based on Clarke's 3 He/ 4 He instrument of McMaster University. The principal special features of the MM3000 are: (i) The double collector system, which uses an electron multiplier for the small 3 He + ion beams and a conventional Faraday detector for 4 He + ; (ii) The high sensitivity ion source; and (iii) The low-volume analyser tube employing static vacuum techniques. The sensitivity, resolution and background of the system are designed to permit measurement of 3 He and 4 He levels of the order of 10 -12 cm 3 STP and 10 -6 cm 3 STP, respectively, with a precision of 0.5%, although smaller quantities are detectable. The inherent resolution of the instrument is well in excess of 2000, but a resolution of 600-1000 is normally used for the 3 He + collector as this is sufficient to separate 3 He + from any interfering HD + or H + 3 ions. At this resolution 900 ions per second of 3 He + ions are obtained from 10 -12 cm 3 STP of 3 He. This is the size of 3 He samples obtained from water samples containing tritium at levels around 200 tritium units (1 tritium unit (TU) = IT/10 18 H). At lower tritium levels the 3 He + signal is correspondingly reduced, but the same techniques (described below) allow signals from 1-TU samples (5 ions/s) to be measured with good precision. The limit of detection is reached with quantities of 3 He in the region of 10 -15 cm 3 STP and tritium levels of around 0.1 TU. (author)

Investigation of radial dose effect on single event upset cross-section due to heavy ions using GEANT4

International Nuclear Information System (INIS)

Boorboor, S.; Feghhi, S.A.H.; Jafari, H.

2015-01-01

The heavy ions are the main cause to produce single event upset (SEU) damage on electronic devices since they are high LET radiations. The dimension of electronic components in new technology, arise a challenge in radiation effect estimations. Accurate investigations require fully considering the ion track in energy deposition as a radial dose distribution. In this work, the distribution of delta rays as well as LET have been calculated to determine ionization structure around ion track by a Monte Carlo code, GEANT4. The radial dose of several heavy ions with different energy in silicon was investigated and compared with the works by other authors in this field. The results showed that heavy ions with identical LET can have different SEU cross-section in silicon transistors. As a demonstrative example, according to our results, the error probability for 4.8 GeV iron was 8 times greater than that for 15 MeV carbon ions, in transistors with new process technology which have small dimension and low critical charges. Our results show that considering radial dose distribution considerably improves the accuracy of the SEU cross-section estimation in electronic devices especially for new technologies. - Highlights: • The single event upset is produced by heavy ions interaction on electronic devices. • The radial dose of several heavy ions in silicon was calculated by GEANT4. • Heavy ions with identical LET had different SEU cross-section in silicon transistors. • Low dimension and critical charge devices were more sensitive to radial dose effect

CERN Heavy-Ion Facility design report

International Nuclear Information System (INIS)

Warner, D.; Angert, N.; Bourgarel, M.P.; Brouzet, E.; Cappi, R.; Dekkers, D.; Evans, J.; Gelato, G.; Haseroth, H.; Hill, C.E.; Hutter, G.; Knott, J.; Kugler, H.; Lombardi, A.; Lustig, H.; Malwitz, E.; Nitsch, F.; Parisi, G.; Pisent, A.; Raich, U.; Ratzinger, U.; Riccati, L.; Schempp, A.; Schindl, K.; Schoenauer, H.; Tetu, P.; Umstaetter, H.H.; Rooij, M. van; Weiss, M.

1993-01-01

The design of the CERN Heavy-Ion Facility is described. This facility will be based on a new ion linear accelerator (Linac 3), together with improvements to the other accelerators of the CERN complex to allow them to cope with heavy ions, i.e. to the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS) and the Super Proton Synchrotron (SPS). For this reference design, the pure isotope of lead, 208 Pb, is considered. The bulk of the report describes Linac 3, a purpose-built heavy-ion linac mainly designed and constructed in collaboration with several CERN member state laboratories, but also with contributions from non-member states. Modifications and improvements to existing CERN accelerators essentially concern the RF acceleration, beam control and beam monitoring (all machines), beam kickers and septa at the input and output of the PSB, and major vacuum improvements, aiming to reduce the pressure by factors of at least seven and three in the PSB and PS respectively. After injection from the Electron Cyclotron Resonance source at 2.5 keV/u the partially stripped heavy-ion beam is accelerated successively by a Radio Frequency Quadrupole and an Interdigital-H linac to 4.2 MeV/u. After stripping to 208 Pb 53+ , the beam is again accelerated, firstly in the PSB (to 98.5 MeV/u), then in the PS (to 4.25 GeV/u). The final stage of acceleration in the SPS takes the fully stripped 208 Pb 82+ ions to 177 GeV/u, delivering a beam of 4.10 8 ions per SPS supercycle (15.2 s) to the experiments. The first physics run with lead ions is scheduled for the end of 1994. Finally, some requirements for carrying out heavy-ion physics at the Large Hadron Collider are mentioned. (orig.)

Heavy-ion targets

International Nuclear Information System (INIS)

Adair, H.L.; Kobisk, E.H.

1985-01-01

This chapter examines the characteristics of targets required in heavy-ion accelerator physics experiments. The effects of target parameters on heavy-ion experimental results are reviewed. The target fabrication and characterization techniques used to minimize experimental problems during heavy-ion bombardment are described. Topics considered include target thickness and uniformity, target lifetime, target purity, substrate materials, Doppler shift effects, metal preparations, and target preparation methods

Damage of niobium surfaces caused by bombardment with 4He+ ions of different energies typical for T-20

International Nuclear Information System (INIS)

Guseva, M.I.; Gusev, V.; Martynenko, Yu.V.; Das, S.K.; Kaminsky, N.

1979-01-01

The surface damage of cold worked and annealed polycrystalline Nb irradiated at room temperature with He + ions sequentially at different energies over the range from 0.5 keV to 1.8 MeV has been investigated. The individual energy and the dose of the He + ion was chosen to match the theoretically calculated He + ion spectrum expected in the Tokamak T-20. In one set of irradiations, targets were irradiated at Kurchatov Institute starting with 0.5 keV 4 He + ions and extending up to 90 keV in eleven steps. Subsequently, the same area was irradiated at ANL starting at 150 keV and increased in eight steps up to 1.8 MeV. The irradiations were carried out for a total dose of 5.0 C/cm 2 . In another set of irradiations the sequence was reversed. Scanning electron microscopy results show formation of blisters and exfoliation. For the same dose the broad energy implant (due to sequential irradiation) appears to decrease the blister diameter and density as compared to irradiation with monoenergetic He + ions at a given energy (in the energy range considered). Some estimates of surface erosion yields due to blistering are given

Structure of heavy-ion tracks in zircon

International Nuclear Information System (INIS)

Braunshausen, G.; Bursill, L.A.; Vetter, J.; Spohr, R.

1990-01-01

Gem quality zirconas (ZrSiO 4 ) were irradiated with 14MeV/u Pb ions. Observations of heavy-ion tracks confirmed that fission or heavy-ion irradiation damage is confined to a 50-100 Aangstroem core region, which has undergone a crystalline-glass phase transition. 3 refs., 3 figs

Effects of energetic heavy ions on electromagnetic ion cyclotron wave generation in the plasmapause region

International Nuclear Information System (INIS)

Kozyra, J.U.; Cravens, T.E.; Nagy, A.F.; Fontheim, E.G.; Ong, R.S.B.

1984-01-01

An expression for the linear electromagnetic ion cyclotron convective growth rate has been derived, considering multiple ions in the energetic anisotropic component of the plasma (which provides the free energy for the instability) as well as in the cold component of the plasma. This represents a modification of recent treatments investigating electromagnetic ion cyclotron growth rates which have considered only hydrogen ions in the energetic component. Four major effects on the growth and propagation characteristics result from inclusion of heavy ions in the energetic component. Some wave growth occurs at low frequencies below the corresponding marginally unstable wave mode for each heavy ion. Enhanced quasi-monochronomatic peaks in the convective growth rate appear just below the O + and He + gyrofrequency and can be quite pronounced for certain plasma conditions. Stop bands, decreased group velocity and other effects normally attributed to cold heavy ions can be produced or enhanced by heavy ions in the energetic plasma component. Partial or complete suppression of wave growth at frequencies above the marginally unstable wave mode for a particular energetic heavy ion can greatly alter the growth rates that would occur in the absence of this energetic heavy ion. The expression for the linear electromagnetic ion cyclotron convective growth rate along with appropriate plasma parameters was used to investigate the nature of linear wave growth in the plasmapause region. The frequencies of peaks in the convective growth rate given by this model compare favorably with wave measurements in this region. It is conceivable that through wave-particle interactions, electromagnetic ion cyclotron waves could supply the energy source for various plasmapause region phenomena such as the O + torus, the plasma cloak and stable auroral red arcs

Heavy ion physics

International Nuclear Information System (INIS)

Kalpakchieva, R.; Cherepanov, E.A.

1993-01-01

The international school-seminar on heavy ion physics had been organized in Dubna in may of 1993. The scientific program of reports covers the following main topics: synthesis and properties of heavy nuclei; synthesis and investigation of properties of exotic nuclei; experiments with radioactive nuclear beams; interaction between complex nuclei at low and intermediate energies. It also includes reports on laser spectroscopy and exotic nuclear beams, on some application of heavy ion beams for the problems of solid state physics, on construction of multidetector facilities and on developing of heavy ion accelerator complexes. Short communication

Infrared spectra of 4HeH+, 4HeD+, 3HeH+, and 3HeD+

International Nuclear Information System (INIS)

Crofton, M.W.; Altman, R.S.; Haese, N.N.; Oka, T.

1989-01-01

Isotopic species of the HeH + molecular ion provide an excellent testing ground for studying isotopic dependence of vibration--rotation constants because of the small masses of He and H isotopes. We have observed infrared spectra of the hot band v=2 left-arrow 1 of HeH + and fundamental bands of isotopic species HeD + , 3 HeH + , and 3 HeD + , and obtained the Dunham coefficients Y kl , and the isotopically independent parameters U kl , Δ He kl , and Δ H kl

Charge-transfer cross sections of ground state He+ ions in collisions with He atoms and simple molecules in the energy range below 4.0 keV

International Nuclear Information System (INIS)

Kusakabe, Toshio; Kitamuro, Satoshi; Nakai, Yohta; Tawara, Hiroyuki; Sasao, Mamiko

2012-01-01

Charge-transfer cross sections of the ground state He + ions in collisions with He atoms and simple molecules (H 2 , D 2 , N 2 , CO and CO 2 ) have been measured in the energy range of 0.20 to 4.0 keV with the initial growth rate method. Since previously published experimental data are scattered in the low energy region, the present observations would provide reasonably reliable cross section data below 4 keV. The charge transfer accompanied by dissociation of product molecular ion can be dominant at low energies for molecular targets. In He + + D 2 collisions, any isotope effect was not observed over the present energy range, compared to H 2 molecule. (author)

The heavy ion injection scheme for RHIC [Relativistic Heavy Ion Collider

International Nuclear Information System (INIS)

Rhoades-Brown, M.J.

1989-01-01

The Relativistic Heavy Ion Collider (RHIC) at Brookhaven has a multi-component injection system. The Collider requires very heavy ions such as 79 197 Au to be injected fully stripped of atomic electrons, at a kinetic energy of approximately 10 GeV/nucleon. However, the heavy ions are produced initially at a negative ion source and accelerated first in a 15 MV Tandem. These partially stripped ions have a kinetic energy of approximately 1 MeV/nucleon on leaving the Tandem. In order to achieve the injection requirements for RHIC, the partially stripped ions are accelerated in the Booster (currently under construction) and pass through a stripping foil on their way to the Alternating Gradient Synchrotron (AGS), where they are further accelerated before injection into RHIC. Recent theoretical calculations have shown quite convincingly that very heavy ions with 2 electrons in the filled K-shell may be accelerated with negligible loss in the AGS. 13 refs., 3 figs., 3 tabs

Progress Toward Heavy Ion IFE

International Nuclear Information System (INIS)

Meier, W.R.; Logan, B.G.; Waldron, W.L.; Sabbi, G.L.; Callahan-Miller, D.A.; Peterson, P.F.; Goodin, D.T.

2002-01-01

Successful development of Heavy Ion Fusion (HIF) will require scientific and technology advances in areas of targets, drivers and chambers. Design work on heavy ion targets indicates that high gain (60-130) may be possible with a -3-6 MJ driver depending on the ability to focus the beams to small spot sizes. Significant improvements have been made on key components of heavy ion drivers, including sources, injectors, insulators and ferromagnetic materials for long-pulse induction accelerator cells, solid-state pulsers, and superconducting quadrupole magnets. The leading chamber concept for HIF is the thick-liquid-wall HYLEE-II design, which uses an array of flibe jets to protect chamber structures from x-ray, debris, and neutron damage. Significant progress has been made in demonstrating the ability to create and control the types of flow needed to form the protective liquid blanket. Progress has also been made on neutron shielding for the final focus magnet arrays with predicted lifetimes now exceeding the life of the power plant. Safety analyses have been completed for the HYLEE-II design using state-of-the-art codes. Work also continues on target fabrication and injection for HE. A target injector experiment capable of > 5 Hz operation has been designed and construction will start in 2002. Methods for mass production of hohlraum targets are being evaluated with small-scale experiments and analyses. Progress in these areas will be reviewed

Heavy ion inertial fusion

International Nuclear Information System (INIS)

Fessenden, T.J.; Friedman, A.

1991-01-01

This report describes the research status in the following areas of research in the field of heavy ion inertial fusion: (1) RF accelerators, storage rings, and synchrotrons; (2) induction linacs; (3) recirculation induction accelerator approach; (4) a new accelerator concept, the ''Mirrortron''; (5) general issues of transport, including beam merging, production of short, fat quadrupoles with nearly linear focusing, calculations of beam behaviour in image fields; 3-D electrostatic codes on drift compression with misalignments and transport around bends; (6) injectors, ion sources and RFQs, a.o., on the development of a 27 MHz RFQ to be used for the low energy portion of a new injector for all ions up to Uranium, and the development of a 2 MV carbon ion injector to provide 16 C + beams of 0.5 A each for ILSE; (7) beam transport from accelerator to target, reporting, a.o., the feasibility to suppress third-order aberrations; while Particle-in-Cell simulations on the propagation of a non-neutral ion beam in a low density gas identified photo-ionization by thermal X-rays from the target as an important source of defocusing; (9) heavy ion target studies; (10) reviewing experience with laser drivers; (11) ion cluster stopping and muon catalyzed fusion; (12) heavy ion systems, including the option of a fusion-fission burner. 1 tab

Studies of Limits on Uncontrolled Heavy Ion Beam Losses for Allowing Hands-On Maintenance

Energy Technology Data Exchange (ETDEWEB)

Reginald M. Ronningen; Igor Remec

2010-09-11

Dose rates from accelerator components activated by 1 W/m beam losses are obtained semiempirically for a 1 GeV proton beam and by use of Monte Carlo transport codes for the proton beam and for 777 MeV/u 3He, 500 MeV/u 48Ca, 86Kr, 136Xe, and 400 MeV/u 238U ions. The dose rate obtained by the semi-empirical method, 0.99 mSv/h (99 mrem/h) at 30 cm, 4 h after 100 d irradiation by a 1-GeV proton beam, is consistent with studies at several accelerator facilities and with adopted hands-on maintenance dose rate limits. Monte Carlo simulations verify this result for protons and extend studies to heavy ion beam losses in drift-tube linac and superconducting linac accelerating structures. The studies indicate that the 1 W/m limit imposed on uncontrolled beam losses for high-energy proton beams might be relaxed for heavy ion beams. These studies further suggest that using the ratio of neutrons produced by a heavy ion beam to neutrons produced by a proton beam along with the dose rate from the proton beam (for thin-target scenarios) should allow an estimate of the dose rates expected from heavy ion beam losses.

Irradiation effect of different heavy ions and track section on the silkworm Bombyx mori

Energy Technology Data Exchange (ETDEWEB)

Tu Zhenli E-mail: tu514@yahoo.co.jp; Kobayashi, Yasuhiko; Kiguchi, Kenji; Watanabe, Hiroshi

2003-05-01

In order to compare the irradiation effects of different ions, wandering larvae were whole-body exposed or locally irradiated with 50-MeV {sup 4}He{sup 2+}, 220-MeV {sup 12}C{sup 5+}, and 350-MeV {sup 20}Ne{sup 8+} ions, respectively. For the whole-body-exposed individuals, the survival rates at the cocooning, pupation, and emergence stages all decreased as dose increased, and a range-dependent difference was clearly observed. For local irradiation of ovaries, irradiation effects depend very strongly on the projectile range. In the case of local irradiation of dermal cells by different track sections of heavy ions, the closer the target was to the high-LET section of the track, the more pronounced were the radiation effects. These results indicated that by selectively using ion species and adjusting the irradiation depth to the target, heavy-ion radiosurgery on particular tissues or organs of small experimental animals can be performed more accurately.

Irradiation effect of different heavy ions and track section on the silkworm Bombyx mori

International Nuclear Information System (INIS)

Tu Zhenli; Kobayashi, Yasuhiko; Kiguchi, Kenji; Watanabe, Hiroshi

2003-01-01

In order to compare the irradiation effects of different ions, wandering larvae were whole-body exposed or locally irradiated with 50-MeV 4 He 2+ , 220-MeV 12 C 5+ , and 350-MeV 20 Ne 8+ ions, respectively. For the whole-body-exposed individuals, the survival rates at the cocooning, pupation, and emergence stages all decreased as dose increased, and a range-dependent difference was clearly observed. For local irradiation of ovaries, irradiation effects depend very strongly on the projectile range. In the case of local irradiation of dermal cells by different track sections of heavy ions, the closer the target was to the high-LET section of the track, the more pronounced were the radiation effects. These results indicated that by selectively using ion species and adjusting the irradiation depth to the target, heavy-ion radiosurgery on particular tissues or organs of small experimental animals can be performed more accurately

Heavy ion acceleration at the AGS

International Nuclear Information System (INIS)

Lee, Y.Y.

1989-01-01

The Brookhaven AGS is alternating gradient synchrotron, 807 meters in circumference, which was originally designed for only protons. Using the 15 MV Brookhaven Tandem Van de Graaff as an injector, the AGS started to accelerate heavy ions of mass lighter than sulfur. Because of the relatively poor vacuum (∼10 -8 Torr), the AGS is not able to accelerate heavier ions which could not be fully stripped of electrons at the Tandem energy. When the AGS Booster, which is under construction, is completed the operation will be extended to all species of heavy ions including gold and uranium. Because ultra-high vacuum (∼10 -11 Torr) is planned, the Booster can accelerate partially stripped elements. The operational experience, the parameters, and scheme of heavy ion acceleration will be presented in detail from injection to extraction, as well as future injection into the new Relativistic Heavy Ion Collider (RHIC). A future plan to improve intensity of the accelerator will also be presented. 5 figs., 4 tabs

The GOES-16 Energetic Heavy Ion Sensor (EHIS) Ion Composition and Flux Measurements

Science.gov (United States)

Connell, J. J.; Lopate, C.

2017-12-01

The Energetic Heavy Ion Sensor (EHIS) was built by the University of New Hampshire, subcontracted to Assurance Technology Corporation, as part of the Space Environmental In-Situ Suite (SEISS) on the new GOES-16 satellite (formerly GOES-R) in Geostationary orbit. EHIS measures energetic ions over the range 10-200 MeV for protons, and energy ranges for heavy ions corresponding to the same stopping range (e.g., 19-207 MeV/u for carbon and 38-488 MeV/u for iron). EHIS uses the Angle Detecting Inclined Sensors (ADIS) technique to provide single-element charge resolution. Though on an operational mission for Space Weather monitoring, EHIS can thus provide a new source of high quality Solar Particle Event (SPE) data for science studies. With a high rate of on-board processing ( 2000 events/s), EHIS will provide exceptional statistics for ion composition measurements in large SPEs. For the GOES Level 1-B and Level 2 data products, heavy ions are distinguished in EHIS using pulse-height analysis with on-board processing producing charge histograms for five energy bands. Fits to these data are normalized to priority rate data on the ground. The instrumental cadence for histograms is 1 minute and the primary Level 1-B heavy ion data products are 1-minute and 5-minute averages. We discuss the preliminary EHIS heavy ion data results which show elemental peaks from H to Fe, with peaks for the isotopes D and 3He. (GOES-16 was launched in 19 November, 2016 and data has, though July 2017, been dominated by Galactic Cosmic Rays.) The EHIS instrument development project was funded by NASA under contract NNG06HX01C.

Lateral variations of radiobiological properties of therapeutic fields of 1H, 4He, 12C and 16O ions studied with Geant4 and microdosimetric kinetic model

Science.gov (United States)

Dewey, Sophie; Burigo, Lucas; Pshenichnov, Igor; Mishustin, Igor; Bleicher, Marcus

2017-07-01

As known, in cancer therapy with ion beams the relative biological effectiveness (RBE) of ions changes in the course of their propagation in tissues. Such changes are caused not only by increasing the linear energy transfer (LET) of beam particles with the penetration depth towards the Bragg peak, but also by nuclear reactions induced by beam nuclei leading to the production of various secondary particles. Although the changes of RBE along the beam axis have been studied quite well, much less attention has been paid to the evolution of RBE in the transverse direction, perpendicular to the beam axis. In order to fill this gap, we simulated radiation fields of 1H, 4He, 12C and 16O nuclei of 20 mm in diameter by means of a Geant4-based Monte Carlo model for heavy-ion therapy connected with the modified microdosimetric kinetic model to describe the response of normal ((α/β)_x-rays=3.8 Gy) and early-responding ((α/β)_x-rays=10 Gy) tissues. Depth and radial distributions of saturation-corrected dose-mean lineal energy, RBE and RBE-weighted dose are investigated for passive beam shaping and active beam scanning. The field of 4He has a small lateral spread as compared with 1H field, and it is characterised by a modest lateral variation of RBE suggesting the use of fixed RBE values across the field transverse cross section at each depth. Reduced uncertainties of RBE on the boundary of a 4He treatment field can be advantageous in a specific case of an organ at risk located in lateral proximity to the target volume. It is found that the lateral distributions of RBE calculated for 12C and 16O fields demonstrate fast variations in the radial direction due to changes of dose and composition of secondary fragments in the field penumbra. Nevertheless, the radiation fields of all four projectiles at radii larger than 20 mm can be characterized by a common RBE value defined by tissue radiosensitivity. These findings can help, in particular, in accessing the transverse

Performance of MBE-4: An experimental multiple beam induction linear accelerator for heavy ions

International Nuclear Information System (INIS)

Warwick, A.I.; Fessenden, T.J.; Keefe, D.; Kim, C.H.; Meuth, H.

1988-06-01

An experimental induction linac, called MBE-4, has been constructed to demonstrate acceleration and current amplification of multiple heavy ion beams. This work is part of a program to study the use of such an accelerator as a driver for heavy ion inertial fusion. MBE-4 is 16m long and accelerates four space-charge-dominated beams of singly-charged cesium ions, in this case from 200 keV to 700 keV, amplifying the current in each beam from 10mA by a factor of nine. Construction of the experiment was completed late in 1987 and we present the results of detailed measurements of the longitudinal beam dynamics. Of particular interest is the contribution of acceleration errors to the growth of current fluctuations and to the longitudinal emittance. The effectiveness of the longitudinal focusing, accomplished by means of the controlled time dependence of the accelerating fields, is also discussed. 4 refs., 5 figs., 1 tab

Heavy-ion dosimetry

International Nuclear Information System (INIS)

Schimmerling, W.

1980-03-01

This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained

Solar wind heavy ions from energetic coronal events

International Nuclear Information System (INIS)

Bame, S.J.

1978-01-01

Ions heavier than those of He can be resolved in the solar wind with electrostatic E/q analyzers when the local thermal temperatures are low. Ordinarily this condition prevails in the low speed solar wind found between high speed streams, i.e. the interstream, IS, solar wind. Various ions of O, Si and Fe are resolved in IS heavy ion spectra. Relative ion peak intensities indicate that the O ionization state is established in the IS coronal source regions at approx. 2.1 x 10 6 K while the state of Fe is frozen in at approx. 1.5 x 10 6 K farther out. Occasionally, anomalous spectra are observed in which the usually third most prominent ion peak, O 8+ , is depressed as are the Fe peaks ranging from Fe 12+ to Fe 7+ . A prominent peak in the usual Si 8+ position of IS spectra is self-consistently shown to be Fe 16+ . These features demonstrate that the ionization states were frozen in at higher than usual coronal temperatures. The source regions of these hot heavy ion spectra are identified as energetic coronal events including flares and nonflare coronal mass ejections. 24 references

Simulation and dosimetric analysis of protons, {sup 4}He ions and {sup 12}C ions beams for brain neoplasm therapy; Simulacao e analise dosimetrica de feixes de protons e ions de {sup 4}He e {sup 12}C em tratamento de tumor cerebral

Energy Technology Data Exchange (ETDEWEB)

Santos, Guilherme M.; Mello, Victor Barreto Braga [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil); Mello Neto, Joao R.T. de [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

2016-07-01

This study aims to simulate protons, {sup 4}He ions and {sup 12}C ions beams, radiating the head of an average-sized man with the purpose of treating a hypothalamic tumor. GEANT4 was used to simulate the head (skin, skull and brain), and the beam, giving their characteristics and also the physical processes involved. The results sought herein are graphs of depth for relative dose for each of the three particles incident on the settings mentioned above. (author)

Charge transfer processes in collisions of Si{sup 4+} ions with He atoms at intermediate energies

Energy Technology Data Exchange (ETDEWEB)

Suzuki, R. [Hitotsubashi Univ., Tokyo (Japan). Computer Center; Watanabe, A. [Dept. of Information Sciences, Ochanomizu Univ., Tokyo (Japan); Sato, H. [Graduate School of Humanities and Sciences, Ochanomizu Univ., Tokyo (Japan); Gu, J.P.; Hirsch, G.; Buenker, R.J. [Wuppertal Univ. (Gesamthochschule) (Germany). Lehrgebiet Theoretische Chemie; Kimura, M. [Graduate School of Science and Engineering, Yamaguchi Univ., Ube (Japan); Stancil, P.C. [Georgia Univ., Athens, GA (United States). Dept. of Physics

2001-07-01

Charge transfer in collisions of Si{sup 4+} ions with He atoms below 100 keV/u is studied by using a molecular orbital representation within both the semiclassical and quantal representations. Single transfer reaction Si{sup 4+} + He {yields} Si{sup 3+} + He{sup +} has been studied by a number of theoretical investigations. In addition to the reaction (1), the first semiclassical MOCC calculations are performed for the double transfer channel Si{sup 4+} + He {yields} Si{sup 2+} + He{sup 2+}. Nine molecular states that connect both with single and double electron transfer processes are considered in the present model. Electronic states and corresponding couplings are determined by the multireference single- and double- excitation configuration interaction method. The present cross sections tie well with the earlier calculations of Stancil et al., (1997) at lower energies, but show a rather different magnitude from those of Bacchus-Montabonel and Ceyzeriat, (1998). The present rate constant is found to be significantly different from the experimental finding of Fang and Kwong, (1996) at 4,600 K, and hence does not support the experiment. (orig.)

Beam modulation for heavy ion radiotherapy

International Nuclear Information System (INIS)

Kanai, T.; Minohara, S.; Sudou, M.

1993-01-01

The first clinical trial of heavy ion radiation therapy is scheduled in 1994 by using the heavy ion medical accelerator in Chiba (HIMAC). In order to start the clinical trial, first, it is necessary to know the physical characteristics of high energy heavy ions in human bodies, for example, dose and linear energy transfer (LET) distribution. Also the knowledge on the biological effectiveness of heavy ions is required. Based on these biophysical properties of heavy ions, monoenergetic heavy ion beam should be modulated so as to make the spread Bragg peak suitable to heavy ion radiation therapy. In order to establish a methodology to obtain the most effective spread Bragg peak for heavy ion radiation therapy, a heavy ion irradiation port at the RIKEN ring cyclotron facility was constructed. By using a 135 MeV/u carbon beam, the biophysical properties of the heavy ions were investigated, and a range modulator was designed to have uniform biological response in the spread Bragg peak. The physical and biological rationality of the spread Bragg peak were investigated. The dose, LET and biological effect of a monoenergetic heavy ion beam, the design of the range modulator, and the distributions of LET and biological dose for the spread Bragg peak are reported. (K.I.)

Design of the compact ECR ion source for heavy-ion therapy

International Nuclear Information System (INIS)

Muramatsu, M.; Kitagawa, A.; Sato, S.; Sato, Y.; Yamada, S.; Hattori, T.; Shibuya, S.

1999-01-01

Heavy ion cancer treatment is successfully being done at the Heavy Ion Medical Accelerator in Chiba (HIMAC). Design philosophy for the ion sources for medical facilities are as follows: sufficient beam intensity, a few hundred eμA; long lifetime with good stability; easy operation and easy maintenance; and compactness. In order to develop such source for future heavy-ion facilities, we have tested compact electron cyclotron resonance (ECR) ion sources using permanent magnets both for axial and radial confinement of hot electrons. Since the yield of C 2+ ion in the firstly-developed source (2.45 GHz ECR) was 15 eμA and far below the medical requirement (-150 eμA for the HIMAC), a new source has been proposed, having the frequency of 10 GHz. The extracted intensity of C 4+ (and C 2+ ) ions is expected to be higher than 200 eμA. (author)

Charge Transfer Processes in Collisions of Si4+ Ions with He Atoms at Intermediate Energies

Science.gov (United States)

Suzuki, R.; Watanabe, A.; Sato, H.; Gu, J. P.; Hirsch, G.; Buenker, R. J.; Kimura, M.; Stancil, P. C.

Charge transfer in collisions of Si4+ ions with He atoms below 100 keV/u is studied by using a molecular orbital representation within both the semiclassical and quantal representations. Single transfer reaction Si4++He →Si3++He+ has been studied by a number of theoretical investigations. In addition to the reaction (1), the first semiclassical MOCC calculations are performed for the double transfer channel Si4++HE→Si2++He2+ Nine molecular states that connect both with single and double electron transfer processes are considered in the present model. Electronic states and corresponding couplings are determined by the multireference single- and double- excitation configuration interaction method. The present cross sections tie well with the earlier calculations of Stancil et al., Phys. Rev. A 55, 1064 (1997) at lower energies, but show a rather different magnitude from those of Bacchus-Montabonel and Ceyzeriat, Phys. Rev. A 58, 1162 (1998). The present rate constant is found to be significantly different from the experimental finding of Fang and Kwong, Phys. Rev. A 59, 342 (1996) at 4,600 K, and hence does not support the experiment.

Studies of Limits on Uncontrolled Heavy Ion Beam Losses for Allowing Hands-On Maintenance. Final report

International Nuclear Information System (INIS)

Ronningen, Reginald M.; Remec, Igor

2010-01-01

Dose rates from accelerator components activated by 1 W/m beam losses are obtained semiempirically for a 1 GeV proton beam and by use of Monte Carlo transport codes for the proton beam and for 777 MeV/u 3He, 500 MeV/u 48Ca, 86Kr, 136Xe, and 400 MeV/u 238U ions. The dose rate obtained by the semi-empirical method, 0.99 mSv/h (99 mrem/h) at 30 cm, 4 h after 100 d irradiation by a 1-GeV proton beam, is consistent with studies at several accelerator facilities and with adopted hands-on maintenance dose rate limits. Monte Carlo simulations verify this result for protons and extend studies to heavy ion beam losses in drift-tube linac and superconducting linac accelerating structures. The studies indicate that the 1 W/m limit imposed on uncontrolled beam losses for high-energy proton beams might be relaxed for heavy ion beams. These studies further suggest that using the ratio of neutrons produced by a heavy ion beam to neutrons produced by a proton beam along with the dose rate from the proton beam (for thin-target scenarios) should allow an estimate of the dose rates expected from heavy ion beam losses.

First phase plan for experimental study of heavy-ion inertial fusion accelerator

International Nuclear Information System (INIS)

Hattori, Toshiyuki; Okamura, Masahiro; Oguri, Yoshiyuki; Aida, Toshihiro; Takeuchi, Kouichi; Sasa, Kimikazu; Itoh, Takashi; Okada, Masashi; Takahashi, Yousuke; Ishii, Yasuyuki.

1993-01-01

We propose the basic experiment plan of driver for heavy-ion inertial fusion by heavy-ion linac [1-3] system and the heavy-ion cooler synchrotron. As the first phase of planning, we will improve old heavy-ion accelerator system that accelerate small intensity around Cl ion with charge to mass ratio of 1/4 up to 2.4 MeV/amu. The injector of the system will exchange from the 1.6 MV Peletron Tandem accelerator to an RFQ type linac with an ECR heavy-ion source. According to building up the power sources of RF and focusing magnet, then it is able to accelerate intense around Xe ion with charge to mass ratio of 1/6 up to 2.4 MeV/amu. At the next stage of it, we will construct a heavy-ion cooler synchrotron having magneticrigidity of 3 or 6 Tm and begin to study about HIF driver. (author)

Heavy-ion irradiation effects on passivated implanted planar silicon detectors

International Nuclear Information System (INIS)

Coster, W. de; Brijs, B.; Vandervorst, W.; Burger, P.

1992-01-01

Commercially available p + nn + passivated implanted planar silicon detectors have been shown to be very performing for standard RBS-analysis with 4 He beams. Lifetimes are found to range up till >10 9 particles. The end of lifetime occurs concurrent with internal breakdown of the detector. Inverted n + np + detectors where the junction is located well outside the damage region, are expected to be less sensitive to the radiation damage and to have a higher lifetime. In the present paper the characteristics for heavy-ion detection of both types of detector are investigated and discussed upon. (orig.)

Relativistic heavy-ion physics

CERN Document Server

Herrera Corral, G

2010-01-01

The study of relativistic heavy-ion collisions is an important part of the LHC research programme at CERN. This emerging field of research focuses on the study of matter under extreme conditions of temperature, density, and pressure. Here we present an introduction to the general aspects of relativistic heavy-ion physics. Afterwards we give an overview of the accelerator facility at CERN and then a quick look at the ALICE project as a dedicated experiment for heavy-ion collisions.

Heavy ion measurement by chemical detectors

International Nuclear Information System (INIS)

Huebner, K.; Erzgraeber, G.; Eichhorn, K.

1979-02-01

In testing the applicability of the threshold system polyvinyl alcohol/methyl orange/chloral hydrate/sodium tetraborate to the quantitative detection of single particles, the chemical detector was irradiated with 4 He, 12 C, 18 O, 22 He ions of different LET. Detectors with 4 different borax concentrations (chloral hydrate concentration kept constant) have been irradiated. The dose causing the colour change increased linearly with the borax concentration. For equal borax concentrations this dose increases with increasing LET due to the decreasing G value of the HCl. The fluence ranges measurable with the various detector compositions are given. 4 He and 18 O ion ranges have been determined. The measured depth dose curves have been corrected because the dose is LET-dependent. The experimentally determined ranges are in good agreement with values calculated for the detector material

On the energy gain enhancement of DT+D3He fuel configuration in nuclear fusion reactor driven by heavy ion beams

Directory of Open Access Journals (Sweden)

S Khoshbinfar

2016-09-01

Full Text Available It is expected that advanced fuels be employed in the second generation of nuclear fusion reactors. Theoretical calculations show that in such a fuel, a high plasma temperature about 100 keV is a requisite for reaction rate improvement of nuclear fusion. However, creating such a temporal condition requires a more powerful driver than we have today. Here, introducing an optimal fuel configuration consisting of DT and D-3He layers, suitable for inertial fusion reactors and driven by heavy ion beams, the optimal energy gain conditions have been simulated and derived for 1.3 MJ system. It was found that, in this new fuel configuration, the ideal energy gain, is 22 percent more comparing with energy gain in corresponding single DT fuel layer. Moreover, the inner DT fuel layer contributed as an ignition trigger, while the outer D3He fuel acts as particle and radiation shielding as well as fuel layer.

On contribution of energetic and heavy ions to the plasma pressure: Storm Sept 27 - Oct 4, 2002

Science.gov (United States)

Kronberg, E. A.; Mouikis, C.; Kistler, L. M.; Dandouras, I. S.; Daly, P. W.; Welling, D. T.; Grigorenko, E. E.

2015-12-01

Contribution of the energetic ions (>> 40 keV) and of heavy ions into the total plasma pressure is often neglected. In this study we evaluate the contribution of these components for the storm observed from September 27 to October 4 in 2002. The thermal component of the pressure for the protons, helium and oxygen at 0--40 keV/q is measured by the Cluster/CIS/CODIF sensor. The contribution of the energetic ions at energies >> 40 keV is calculated from the Cluster/RAPID/IIMS observations. The results show that before the storm has initiated, the contribution of the energetic ions in to the total pressure is indeed negligible in the tail plasma sheet, less than ˜1%. However, with the storm development contribution of the energetic part becomes significant, up to ˜30%, towards the recovery phase and cannot be neglected. Heavy ions contribute to the 27% of the total pressure and half of them are energetic. The contribution of energetic ions to the pressure of the ring current (L≃5) is significant. The heavy ions play a dominant role in the plasma pressure, about 62% during the main phase of the magnetic storm. Half of them are energetic ions. The SWMF/BATS-R-US MHD model underestimates the contribution of the energetic and heavy ions in to the ion distribution in the magnetotail plasma sheet and the ring current. The ring current plasma pressure distorts the terrestrial internal magnetic field and defines magnetic storm. Therefore, it is essential to take in to account the contribution of the energetic and heavy ions.

Effects of Heavy Ions on ULF Wave Resonances Near the Equatorial Region

International Nuclear Information System (INIS)

Lee, D.-H.; Johnson, J.R.; Kim, K.; Kim, K.-S.

2008-01-01

Pc1-2 ULF waves are strongly associated with the presence of various ions in the magnetosphere. We investigate the role of heavy ion resonances in nonuniform plasmas near the equatorial region. By adopting the invariant imbedding method, the coupled plasma wave equations are solved in an exact manner to calculate the resonant absorption at the ion-ion hybrid resonance. Our results show that irreversible mode conversion occurs at the resonance, which absorbs the fast wave energy. It is found that waves near the resonances appear with linear polarization, and their amplitude and frequency are sensitive to the properties of the heavy ion plasma composition. We examine how these resonances occur for various H+ - He+ populations in detail by performing an accurate calculation of the mode conversion efficiency. Because the multi-ion hybrid resonance locations in cold plasmas are determined by simple parameters such as the fraction of the ion number density of each species and the magnetic field, we suggest that it is possible to monitor heavy ion composition by examining the peak frequencies of linearly polarized wave events in either electric field or magnetic field spectral data

Effects of Heavy Ions on ULF Wave Resonances Near the Equatorial Region

Energy Technology Data Exchange (ETDEWEB)

D.-H.Lee, J.R. Johnson, K. Kim and K.-S.Kim

2008-11-20

Pc1-2 ULF waves are strongly associated with the presence of various ions in the magnetosphere. We investigate the role of heavy ion resonances in nonuniform plasmas near the equatorial region. By adopting the invariant imbedding method, the coupled plasma wave equations are solved in an exact manner to calculate the resonant absorption at the ion-ion hybrid resonance. Our results show that irreversible mode conversion occurs at the resonance, which absorbs the fast wave energy. It is found that waves near the resonances appear with linear polarization, and their amplitude and frequency are sensitive to the properties of the heavy ion plasma composition. We examine how these resonances occur for various H+ - He+ populations in detail by performing an accurate calculation of the mode conversion effciency. Because the multi-ion hybrid resonance locations in cold plasmas are determined by simple parameters such as the fraction of the ion number density of each species and the magnetic field, we suggest that it is possible to monitor heavy ion composition by examining the peak frequencies of linearly polarized wave events in either electric field or magnetic field spectral data.

Composition of heavy ions in solar energetic particle events

International Nuclear Information System (INIS)

Fan, C.Y.; Gloeckler, G.

1983-01-01

Recent advances in determining the elemental, charge state, and isotopic composition of approximatelt 1 to 20 MeV per nucleon ions in solar energetic particle (SEP) events and outline our current understanding of the nature of solar and interplanetary processes which may explain the observations. Average values of relative abundances measured in a large number of SEP events were found to be roughly energy independent in the approx. 1 to approx. 20 MeV per nucleon range, and showed a systematic deviation from photospheric abundances which seems to be organized in terms of the first ionization potential of the ion. Direct measurements of the charge states of SEPs revealed the surprisingly common presence of energetic He(+) along with heavy ion with typically coronal ionization states. High resolution measurements of isotopic abundance ratios in a small number of SEP events showed these to be consistent with the universal composition except for the puzzling overabundance of the SEP(22)Ne/(20)Ne relative to this isotopes ratio in the solar wind. The broad spectrum of observed elemental abundance variations, which in their extreme result in composition anomalies characteristic of (3)He rich, heavy ion rich and carbon poor SEP events, along with direct measurements of the ionization states of SEPs provided essential information on the physical characteristics of, and conditions in the source regions, as well as important constraints to possible models for SEP production

Positive ion mobilities in normal liquid 3He at ultralow temperatures

International Nuclear Information System (INIS)

Alexander, P.W.

1978-11-01

The mobility has been measured of positive ions in liquid 3 he in the range 2.5 mK 3 sub(m)/sup(V) 5 sub(m)/sup(V). The effects of 500 p.p.m. 4 He in the 3 He were investigated. It was found that, at low temperatures, several stable ion species could be produced for 3 He pressures of 23 bar and above and, between 25 mK and 60 mK, time dependent conversion from one species of ion to another was observed at all pressures. The creation mechanism, mobility and stability of multiple positive ions were studied. Possible explanations of the phenomena are discussed. The measured drift field dependence of mobility is used to test the quasiparticle scattering model assumed for the liquid. (U.K.)

Computer simulation of range and damage distributions of He ions in SiC

International Nuclear Information System (INIS)

Miyagawa, Yoshiko; Ato, Yasuro; Miyagawa, Soji

1984-01-01

The experimental projected ranges of various heavy ions in an amorphous Si target in the energy region where the nuclear stopping dominates are compared with calculations using the computer simulation program SASAMAL with the Lenz-Jensen, Moliere, Thomas-Fermi and Kalbitzer-Oetzmann (KO) screening parameters. In most cases. the best agreement was obtained with the KO screening parameters. The projected range distributions of He ions implanted in an SiC target were calculated using SASAMAL with KO screening parameters. The agreement between the SASAMAL(KO) results and our experimental data was satisfactory when the electronic stopping parameter k=1.3 k sub(NS) was used. The energy and the depth distributions of the primary knock-on atoms and the depth distributions of the recoil energy density with various values of the displacement energy Esub(d) were also calculated using SASAMAL(KO) for He ions in SiC. (author)

Heavy ion inelastic scattering with a 4π gamma detector

International Nuclear Information System (INIS)

Gross, E.E.

1989-01-01

Heavy-ion inelastic scattering with a new technique that uses a 4π γ-ray detector in coincidence with charged particle detectors is applied to 24 Mg(200 MeV) + 208 Pb scattering. In addition to differential cross sections, a complete particle-γ angular correlation is obtained for decay of the 2 1 + (1.37 MeV) state of 24 Mg. The data are analyzed in coupled-channels. The correlation data proves to be especially sensitive to the static quadrupole moment. 14 refs., 9 figs

Magnetic spectrograph for the Holifield heavy ion research facility

International Nuclear Information System (INIS)

Ford, J.L.C. Jr.; Enge, H.A.; Erskine, J.R.; Hendrie, D.L.; LeVine, M.J.

1977-01-01

The need for a new generation magnetic spectrograph for the Holifield Heavy Ion Research Facility is discussed. The advantages of a magnetic spectrograph for heavy ion research are discussed, as well as some of the types of experiments for which such an instrument is suited. The limitations which the quality of the incident beam, target and spectrograph itself impose on high resolution heavy ion measurements are discussed. Desired features of an ideal new spectrograph are: (1) intrinsic resolving power E/ΔE greater than or equal to 3000; (2) maximum solid angle greater than or equal to 20 msr; (3) dispersion approx. 4-8m; (4) maximum energy interval approx. 30%; and (5) mass-energy product greater than or equal to 200. Various existing and proposed spectrographs are compared with the specifications for a new heavy ion magnet design

Beam losses in heavy ion drivers

CERN Document Server

Mustafin, E R; Hofmann, I; Spiller, P J

2002-01-01

While beam loss issues have hardly been considered in detail for heavy ion fusion scenarios, recent heavy ion machine developments in different labs (European Organization for Nuclear Research (CERN), Gesellschaft fur Schwerionenforschung (GSI), Institute for Theoretical and Experimental Physics (ITEP), Relativistic Heavy-Ion Collider (RHIC)) have shown the great importance of beam current limitations due to ion losses. Two aspects of beam losses in heavy ion accelerators are theoretically considered: (1) secondary neutron production due to lost ions, and (2) vacuum pressure instability due to charge exchange losses. Calculations are compared and found to be in good agreement with measured data. The application to a Heavy-Ion Driven Inertial Fusion (HIDIF) scenario is discussed. 12 Refs.

Spin-isospin excitations induced by heavy ions at Saturne energies

International Nuclear Information System (INIS)

Hennino, T.

1989-01-01

Our program on the Spin-Isospin excitations started with the ( 3 He, 3 H) and ( 2 H, 2 He) reactions was extended with the heavy ion beams available at Saturne ( 12 C, 16 0, 20 Ne and 40 Ar) to study systematically the Δ excitation energy region. Projectile-ejectile dependences were measured. The Δ peak shift appears as a common feature in all charge exchange reactions. The first cross section calculations for the ( 12 C, 12 N) reaction are in good quantitative agreement with the data [fr

Heavy ion fusion

International Nuclear Information System (INIS)

Bangerter, R.O.

1986-01-01

This report on the International Symposium on Heavy Ion Fusion held May 27-29, 1986 summarizes the problems and achievements in the areas of targets, accelerators, focussing, reactor studies, and system studies. The symposium participants recognize that there are large uncertainties in Heavy Ion Fusion but many of them are also optimistic that HIF may ultimately be the best approach to fusion

Heavy ion medical accelerator, HIMAC

International Nuclear Information System (INIS)

Yamada, Satoru

1993-01-01

The heavy ion beam is undoutedly suitable for the cancer treatment. The supriority of the heavy ions over the conventional radiations including protons and neutrons comes mainly from physical characteristics of a heavy particle with multiple charges. A straggling angle due to a multiple Coulomb scattering process in a human body is small for heavy ions, and the small scattering angle results in a good dose localization in a transverse direction. An ionization ratio of the heavy ion beam makes a very sharp peak at the ends of their range. The height of the peak is higher for the heavier ions and shows excellent biomedical effects around Ne ions. In order to apply heavy ion beams to cancer treatment, Heavy Ion Medical Accelerator in Chiba (HIMAC) has been constructed at National Institute of Radiological Sciences. The accelerator complex consists of two ion sources, two successive linac tanks, a pair of synchrotron rings, a beam transport system and an irradiation system. An operation frequency is 100 MHz for two linacs, and the ion energy is 6.0 MeV/u at the output end of the linac. The other four experimental rooms are prepared for basic experiments. The synchrotron accelerates ions up to 800 MeV/u for a charge to mass ratio of 1/2. The long beam transport line provides two vertical beams in addition with two horizontal beams for the treatment. The three treatment rooms are prepared one of which is equipped with both horizontal and vertical beam lines. The whole facility will be open for all scientists who have interests in the heavy ion science as well as the biophysics. The conceptual design study of HIMAC started in 1984, and the construction of the accelerator complex was begun in March 1988. The beam acceleration tests of the injector system was successfully completed in March of this year, and tests of the whole system will be finished throughout this fyscal year. (author)

Stopping power for heavy ions in gases: a comparative study

International Nuclear Information System (INIS)

Diwan, P.K.; Singh, Lakhwant; Singh, Gurinder; Shyam Kumar

1999-01-01

The accurate knowledge of stopping power for heavy ions in gases is of paramount importance in nuclear reaction studies for the identification of reaction products involving ΔE-E telescope detectors. In the present work, it has been calculated the stopping power values for different heavy ions, such as Ne, Ar, Cu, Kr and Ag in various gas absorbers like H 2 , He, N 2 , Ne, Ar, Kr and Xe in the energy domain ∼ 2.5-6 MeV/n using the SRIM-98 code recently developed by Ziegler and the formulations of Benton and Henke, Hubert et al, Mukherjee and Nayak and Northcliffe and Schilling. This study has been undertaken in order to establish the validity of various semiempirical formulations for gas targets

Heavy-ion fusion accelerator research, 1989

International Nuclear Information System (INIS)

1990-06-01

This report discusses the following topics on heavy-ion fusion accelerator research: MBE-4: the induction-linac approach; transverse beam dynamics and current amplification; scaling up the results; through ILSE to a driver; ion-source and injector development; and accelerator component research and development

Data acquisition for the HILI [Heavy Ion Light Ion] detector

International Nuclear Information System (INIS)

Teh, K.M.; Shapira, D.; McConnell, J.W.; Kim, H.; Novotny, R.

1987-01-01

A large acceptance, multi-segmented detector system capable of the simultaneous detection of heavy and light ions has been constructed. The heavy ions are detected with a segmented gas ionization chamber and a multiwire proportional counter while the light ions are detected with a 192 element plastic phoswich hodoscope. Processing the large number of signals is accomplished through a combination of CAMAC and FASTBUS modules and preprocessors, and a Host minicomputer. Details of the data acquisition system and the reasons for adopting a dual standards system are discussed. In addition, a technique for processing signals from an individual hodoscope detector is presented. 4 refs., 3 figs

Nuclear physics with heavy ions. 1

International Nuclear Information System (INIS)

Reif, R.; Schmidt, R.

1981-01-01

Some results obtained in nuclear physics with heavy ions in the energy range up to 10 MeV/nucleon are summarized. A short review of the tendencies in the development of heavy ion accelerators is followed by a classification of the mechanisms observed in heavy ion interactions. The characteristics of the various types of reactions are presented. Applications of heavy ion beams in other branches of sciences are discussed. (author)

Calorimetric low-temperature detectors on semiconductor base for the energy-resolving detection of heavy ions

International Nuclear Information System (INIS)

Kienlin, A. von.

1994-01-01

In the framework of this thesis for the first time calorimetric low-temperature detectors for the energy-resolving detection of heavy ions were developed and successfully applied. Constructed were two different detector types, which work both with a semiconductor thermistor. The temperature increasement effected by a particle incidence is read out. In the first detector type the thermistor was simutaneously used as absorber. The thickness of the germanium crystals was sufficient in order to stop the studied heavy ions completely. In the second type, a composed calorimeter, a sapphire crystal, which was glued on a germanium thermistor, served as absorber for the incident heavy ions. The working point of the calorimeter lies in the temperature range (1.2-4.2 K), which is reachable with a pumped 4 He cryostat. The temperatur increasement of the calorimeter amounts after the incidence of a single α particle about 20-30 μK and that after a heavy ion incidence up to some mK. An absolute energy resolution of 400-500 keV was reached. In nine beam times the calorimeters were irradiated by heavy ions ( 20 Ne, 40 Ar, 136 Xe, 208 Pb, 209 Bi) of different energies (3.6 MeV/nucleon< E<12.5 MeV/nucleon) elastically scattered from gold foils. In the pulse height spectra of the first detector type relatively broad, complex-structurated line shapes were observed. By systematic measurements dependences of the complex line structures on operational parameters of the detector, the detector temperature, and the position of the incident particle could be detected. Together with the results of further experiments a possible interpretation of these phenomena is presented. Contrarily to the complex line structures of the pure germanium thermistor the line shapes in the pulse height spectra, which were taken up in a composite germanium/sapphire calorimeter, are narrow and Gauss-shaped

Resolving key heavy-ion fusion target issues with relativistic heavy-ion research accelerators

International Nuclear Information System (INIS)

Arnold, R.C.

1988-01-01

Heavy-ion accelerators designed for relativistic nuclear research experiments can also be adapted for target research in heavy-ion driver inertial fusion. Needle-shaped plasmas can be created that are adequate for studying basic properties of matter at high energy density. Although the ion range is very long, the specific deposited power nevertheless increases with kinetic energy, as the focus spot can be made smaller and more ions can be accumulated in larger rings

Validating PHITS for heavy ion fragmentation reactions

International Nuclear Information System (INIS)

Ronningen, Reginald M.

2015-01-01

The performance of the Monte Carlo code system PHITS is validated for heavy-ion transport capabilities by performing simulations and comparing results against experimental data from heavy-ion reactions of benchmark quality. These data are from measurements of isotope yields produced in the fragmentation of a 140 MeV/u "4"8Ca beam on a beryllium target and on a tantalum target. The results of this study show that PHITS performs reliably. (authors)

Heavy-ion radiography

International Nuclear Information System (INIS)

Fabrikant, J.I.; Tobias, C.A.; Holley, W.R.; Benton, E.V.

1981-01-01

Heavy-particle radiography has clinical potential as a newly developed noninvasive low-dose imaging procedure that provides increased resolution of minute density differences in soft tissues of the body. The method utilizes accelerated high-energy ions, primarily carbon and neon, at the Bevalac accelerator at the Lawrence Berkeley Laboratory. The research program for medicine utilizes heavy-ion radiography for low-dose mammography, for treatment planning for cancer patients, and for imaging and accurate densitometry of skeletal structures, brain and spinal neoplasms, and the heart. The potential of heavy-ion imaging, and particularly reconstruction tomography, is now proving to be an adjunct to existing diagnostic imaging procedures in medicine, both for applications to the diagnosis, management and treatment of clinical cancer in man, and for the early detection of small soft-tissue tumors at low radiation dose

Studies in heavy ion activation analysis Pt. 4

International Nuclear Information System (INIS)

Lass, B.D.; Ojo, J.F.; Schweikert, E.A.

1980-01-01

The use of 7 MeV 6 Li + for heavy ion activation analysis was investigated. A survey of reactions, involving targets of lithium through oxygen inclusive, were studied for production of β + radioactivation products with half-lives of 10 1 -10 5 seconds. Specific activities for all reactions under the experimental conditions are reported and their use for analysis is assessed. (author)

Investigation of structural materials of reactors using high-energy heavy-ion irradiations

International Nuclear Information System (INIS)

Wang Zhiguang

2007-01-01

Radiation damage in structural materials of fission/fusion reactors is mainly attributed to the evolution of intensive atom displacement damage induced by energetic particles (n, α and/or fission fragments) and high-rate helium doping by direct α particle bombardments and/or (n, α) reactions. It can cause severe degradation of reactor structural materials such as surface blistering, bulk void swelling, deformation, fatigue, embrittlement, stress erosion corrosion and so on that will significantly affect the operation safety of reactors. However, up to now, behavior of structural materials at the end of their service can hardly be fully tested in a real reactor. In the present work, damage process in reactor structural materials is briefly introduced, then the advantages of energetic ion implantation/irradiation especially high-energy heavy ion irradiation are discussed, and several typical examples on simulation of radiation effects in reactor candidate structural materials using high-energy heavy ion irradiations are pronounced. Experimental results and theoretical analysis suggested that irradiation with energetic particles especially high-energy heavy ions is very useful technique for simulating the evolution of microstructures and macro-properties of reactor structural materials. Furthermore, an on-going plan of material irradiation experiments using high energy H- and He-ions based on the Heavy Ion Research Facilities in Lanzhou (HIRFL) is also briefly interpreted. (authors)

Heavy ion accelerators

International Nuclear Information System (INIS)

Schmelzer, C.

1974-01-01

This review of the present state of work on heavy-ion accelerators pays particular attention to the requirements for nuclear research. It is divided into the following sections: single-particle versus collective acceleration, heavy-ion accelerators, beam quality, and a status report on the UNILAC facility. Among the topics considered are the recycling cyclotron, linacs with superconducting resonators, and acceleration to the GeV/nucleon range. (8 figures, 2 tables) (U.S.)

Dose as a function of radial distance from a 930 MeV 4He ion beam

International Nuclear Information System (INIS)

Varma, M.N.; Paretzke, H.; Baum, J.W.; Lyman, J.T.; Howard, J.

1975-01-01

A unique mesh wall ionization chamber (approximating a wall-less ionization chamber) was used to measure dose as a function of radial distance from a 930 MeV 4 He ion beam in air. Measurements were made at distances from about 10 to 40 cm from the ion path. This represents simulated distances of approximately 102 to 404 μm in tissue having a density of 1 g/cm 3 . Experimental values are compared with theoretical calculations, and probable causes of differences found are discussed. (auth)

Heavy-Ion Fusion Accelerator Research, 1991

International Nuclear Information System (INIS)

1992-03-01

This report discusses the following topics: research with multiple- beam experiment MBE-4; induction linac systems experiments; and long- range research and development of heavy-ion fusion accelerators

Recrystallization effects of swift heavy {sup 209}Bi ions irradiation on electrical degradation in 4H-SiC Schottky barrier diode

Energy Technology Data Exchange (ETDEWEB)

Yang, Zhimei; Ma, Yao; Gong, Min [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Li, Yun [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Huang, Mingmin [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Key Laboratory of Radiation Physics and Technology of Ministry of Education, Sichuan University, Chengdu 610064 (China); Gao, Bo [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Zhao, Xin, E-mail: zhaoxin1234@scu.edu.cn [Key Laboratory for Microelectronics, College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

2017-06-15

In this paper, the phenomenon that the recrystallization effects of swift heavy {sup 209}Bi ions irradiation can partially recovery damage with more than 1 × 10{sup 10} ions/cm{sup 2} is investigated by the degradation of the electrical characteristics of 4H-SiC Schottky barrier diode (SBD) with swift heavy ion irradiation. Deep level transient spectroscopy (DLTS) and Current-Voltage (I-V) measurements clearly indicated that E{sub 0.62} defect induced by swift heavy ion irradiation, which was a recombination center, could result in the increase of reverse leakage current (I{sub R}) at fluence less than 1 × 10{sup 9} ions/cm{sup 2} and the recovery of I{sub R} at fluence more than 1 × 10{sup 10} ions/cm{sup 2} in 4H-SiC SBD. The variation tendency of I{sub R} is consisted with the change of E{sub 0.62} defect. Furthermore, it is reasonable explanation that the damage or defect formed at low fluence in SiC may be recovered by further swift heavy ion irradiation with high fluence, which is due to the melting with the ion tracks of the amorphous zones through a thermal spike and subsequent epitaxial recrystallization initiated from the neighboring crystalline regions.

A heavy load for heavy ions

CERN Multimedia

2003-01-01

On 25 September, the two large coils for the dipole magnet of ALICE, the LHC experiment dedicated to heavy ions, arrived at Point 2 on two heavy load trucks after a 1200 km journey from their assembly in Vannes, France.

The composition of heavy ions in solar energetic particle events

International Nuclear Information System (INIS)

Fan, C.Y.

1984-01-01

The composition within individual SEP events may vary both with time and energy, and will in general be different from that in other SEP events. Average values of relative abundances measured in a large number of SEP events, however, are found to be roughly energy independent in the proportional1 to proportional20 MeV per nucleon range, and show a systematic deviation from photospheric abundances which seems to be organized in terms of the first ionization potential of the ion. Direct measurements of the charge states of SEPs have revealed the surprisingly common presence of energetic He + along with heavy ions with typically coronal ionization states. High-resolution measurements of isotopic abundance ratios in a small number of SEP events show these to be consistent with the universal composition except for the puzzling overabundance of the SEP 22 Ne/ 20 Ne relative to this isotopes ratio in the solar wind. The broad spectrum of observed elemental abundance variations, which in their extreme result in composition anomalies characteristic of 3 He-rich, heavy-ion rich and carbon-poor SEP events, along with direct measurements of the ionization states of SEPs provide essential information on the physical characteristics of, and conditions in the source regions, as well as important constraints to possible models for SEP production. (orig./HM)

Heavy ion fusion- Using heavy ions to make electricity

International Nuclear Information System (INIS)

Celata, C.M.

2004-01-01

The idea of using nuclear fusion as a source of commercial electrical power has been pursued worldwide since the 1950s. Two approaches, using magnetic and inertial confinement of the reactants, are under study. This paper describes the difference between the two approaches, and discusses in more detail the heavy-ion-driven inertial fusion concept. A multibeam induction linear accelerator would be used to bring ∼100 heavy ion beams to a few GeV. The beams would then heat and compress a target of solid D-T. This approach is unique among fusion concepts in its ability to protect the reaction chamber wall from neutrons and debris

Heavy-ion superconducting linacs

International Nuclear Information System (INIS)

Delayen, J.R.

1989-01-01

This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs

Heavy-ion superconducting linacs

Energy Technology Data Exchange (ETDEWEB)

Delayen, J.R.

1989-01-01

This paper reviews the status of the superconducting heavy-ion accelerators. Most of them are linacs used as boosters for tandem electrostatic accelerators, although the technology is being extended to very low velocity to eliminate the need for an injector. The characteristics and features of the various superconducting heavy-ion accelerators are discussed. 45 refs.

Heavy flavours in ultra-relativistic heavy ions collisions

International Nuclear Information System (INIS)

Rosnet, Ph.

2008-01-01

The ultra-relativistic collisions of heavy ions are the today's only means to tackle in laboratory conditions the phase diagram in quantum chromodynamics and the strong interaction. The most recent theoretical studies predict a phase transition between the cold nuclear matter (a hadronic gas) and a plasma of quarks and gluons. Heavy flavour can characterize the nuclear matter produced in a heavy ion collision as well as its spatial-temporal evolution. Their study can be made through their decay into muons. The first part of this work presents the issue of ultra-relativistic heavy ion collisions and the role of heavy flavours. In the second part the author reviews the results of experiments performed at RHIC and particularly presents the analysis of the mass spectrum of dimuons in the Phenix experiment. The third part describes the muon trigger system of the Alice experiment at CERN and the expected performances for the study of di-muons

Results of heavy ion radiotherapy

International Nuclear Information System (INIS)

Castro, J.R.

1994-04-01

The potential of heavy ion therapy for clinical use in cancer therapy stems from the biological parameters of heavy charged particles, and their precise dose localization. Biologically, carbon, neon and other heavy ion beams (up to about silicon) are clinically useful in overcoming the radioresistance of hypoxic tumors, thus increasing biological effectiveness relative to low-LET x-ray or electron beams. Cells irradiated by heavy ions show less variation in cell-cycle related radiosensitivity and decreased repair of radiation injury. The physical parameters of these heavy charged particles allow precise delivery of high radiation doses to tumors while minimizing irradiation of normal tissues. Clinical use requires close interaction between radiation oncologists, medical physicists, accelerator physicists, engineers, computer scientists and radiation biologists

Jet-Underlying Event Separation Method for Heavy Ion Collisions at the Relativistic Heavy Ion Collider

OpenAIRE

Hanks, J. A.; Sickles, A. M.; Cole, B. A.; Franz, A.; McCumber, M. P.; Morrison, D. P.; Nagle, J. L.; Pinkenburg, C. H.; Sahlmueller, B.; Steinberg, P.; von Steinkirch, M.; Stone, M.

2012-01-01

Reconstructed jets in heavy ion collisions are a crucial tool for understanding the quark-gluon plasma. The separation of jets from the underlying event is necessary particularly in central heavy ion reactions in order to quantify medium modifications of the parton shower and the response of the surrounding medium itself. There have been many methods proposed and implemented for studying the underlying event substructure in proton-proton and heavy ion collisions. In this paper, we detail a me...

Diogene, a 4π detector for the heavy ion physics with Saturne

International Nuclear Information System (INIS)

Alard, J.P.; Augerat, J.; Babinet, R.

A 4π-detection set up is presently being built around the Saturne II facility, to study central collisions between high energy heavy ions. This set up is essentially composed of a cylindrical drift chamber, triggered by a 30-scintillators multiplicity filter. A schematic description of the detector is given first. Then the present status of the project is presented, at last some progresses on track reconstruction technique with simulated events are given [fr

BROOKHAVEN: Looking towards heavy ion physics

International Nuclear Information System (INIS)

Anon.

1988-01-01

July 11-22 were busy days at Brookhaven with a two-week Summer Institute on Relativistic Heavy Ion Physics. After an intensive first week designed to introduce young physicists to high energy heavy ion research, the second week was a workshop on detector technology for Brookhaven's proposed Relativistic Heavy Ion Collider (RHIC), attended by some 150 physicists

Experimental study of the slowing down of heavy ions at 20 to 100 MeV per nucleon in matter

International Nuclear Information System (INIS)

Herault, J.

1988-01-01

The measurements of typical parameters on heavy ions penetration through matter presented in this work have been performed at the GANIL accelerator facility, using the LISE magnetic spectrometer from 20 to 100 MeV per nucleon. Two magnetic optical configurations of the spectrometer LISE corresponding respectively to energy and angle analysis, have been used. In the first configuration, the analysis of the energy loss distribution, caused by the interaction of the heavy ions beam with the target material, permit to determine the stopping power and the energy straggling. The stopping power is defined experimentally by the ratio of the average energy loss in the target to the thickness of this one. This quantity has been measured for a set of heavy ions ( 17 O, 40 Ar, 86 Kr and 132 Xe) in gaseous media (H 2 , He, N 2 , Ne, Ar, Kr, Xe, CH 4 , C 4 H 10 , CO 2 and CF 4 ) and compared to semi-empirical tabulations. These determinations are compared to those obtained in solid media to study the evolution of the solid-gas difference. This effect vanishes progressively when the projectile tends to be totally stripped (the charge state becomes identical to the atomic number). The heavy ion energy distributions at the exit of degraders and particularly their full width at half maximum have been measured for various projectiles ( 16 O, 40 Ar, 84 Kr, 86 Kr, 100 Mo and 132 Xe) in solid (Be, C, Al, Si, Ti, Ni, Cu, Ag, Ta, Au and Mylar) and gaseous media (the same as for stopping power determinations). A significant contribution of charge exchange straggling to the energy loss straggling is observed for partially stripped ions. A second optical configuration of the beam line LISE has been used, to obtain an image of heavy ions beams passing through targets for various heavy ions ( 16 O, 17 O, 40 Ar, 86 Kr and 100 Mo) in gaseous and solid media. The scaling law for angular straggling is confirmed and extended over five orders of magnitude [fr

Heavy ion fusion

International Nuclear Information System (INIS)

Hofmann, Ingo

1993-01-01

With controlled thermonuclear fusion holding out the possibility of a prolific and clean new source of energy, the goal remains elusive after many years of continual effort. While the conventional Tokamak route with magnetic confinement continues to hit the headlines, other alternatives are now becoming competitive. One possible solution is to confine the thermonuclear fuel pellet by high power beams. Current research and perspectives for future work in such inertial confinement was the subject of the 'Prospects for Heavy Ion Fusion' European Research Conference held in Aghia Pelaghia, Crete, last year. Its main focus was on the potential of heavy ion accelerators as well as recent advances in target physics with high power lasers and light ion beams. Carlo Rubbia declared that high energy accelerators, with their high efficiency, are the most promising approach to economical fusion energy production. However the need for cost saving in the driver accelerator requires new ideas in target design tailored to the particularities of heavy ion beams, which need to be pushed to the limits of high current and phase space density at the same time

Solar wind contribution to the average population of energetic He+ and He++ ions in the Earth's magnetosphere

Directory of Open Access Journals (Sweden)

G. Kremser

1994-01-01

Full Text Available Measurements with the ion charge-energy-mass spectrometer CHEM on the AMPTE/CCE spacecraft were used to investigate the origin of energetic He+ and He++ ions observed in the equatorial plane at 3 ≤ L ≤ 9. Special emphasis was laid on the dependence of long-term average distributions on magnetic local time (MLT and the geomagnetic activity index Kp. The observations are described in terms of the phase space densities f1 (for He+ and f2 (for He++. They confirm preliminary results from a previous study: f1 is independent of MLT, whereas f2 is much larger on the nightside than on the dayside. They show, furthermore, that f1 increases slightly with Kp on intermediate drift shells, but decreases on high drift shells (L ≥ 7. f2 increases with Kp on all drift shells outside the premidnight sector. Within this sector a decrease is observed on high drift shells. A simple ion tracing code was developed to determine how and from where the ions move into the region of observations. It provides ion trajectories as a function of the ion charge, the magnetic moment and Kp. The ion tracing enables a distinction between regions of closed drift orbits (ring current and open convection trajectories (plasma sheet. It also indicates how the outer part of the observation region is connected to different parts of the more distant plasma sheet. Observations and tracing show that He++ ions are effectively transported from the plasma sheet on convection trajectories. Their distribution in the observation region corresponds to the distribution of solar wind ions in the plasma sheet. Thus, energetic He++ ions most likely originate in the solar wind. On the other hand, the plasma sheet is not an important source of energetic He+ ions. Convection trajectories more likely constitute a sink for He+ ions, which may diffuse onto them from closed drift orbits and then get lost through the magnetopause. An ionospheric origin of energetic He+ ions is unlikely as well, since

Spectroscopy of heavy few-electron ions

International Nuclear Information System (INIS)

Mokler, P.H.

1986-07-01

In this paper we ask first, why is it interesting to investigate heavy-few electron ions. Then the various accelerator-based methods to produce heavy few-electron ions are discussed. In the main part an overview on available heavy few-electron ion data and current experiments is given. The summary will end up with future aspects in this field. (orig.)

Polarization phenomena in heavy-ion reactions

International Nuclear Information System (INIS)

Sugimoto, K.; Ishihara, M.; Takahashi, N.

1984-01-01

This chapter presents a few key experiments which provide direct evidence of the polarization phenomena in heavy-ion reactions. The theory of polarization observables and measurements is given with the necessary formulae. The polarization phenomena is described and studies of product nuclear polarization in heavy-ion reactions are discussed. Studies of heavy-ion reactions induced by polarized beams are examined

Heavy ion scattering: High energy limits of RBS and ERD

International Nuclear Information System (INIS)

Rauhala, E.

1994-01-01

Elastic scattering of 7 Li ions by oxygen and 12 C, 14 N and 16 O ions by aluminum, silicon, titanium and sulfur have been studied below the Coulomb barrier energies 3-30 MeV in the angular range of 78 degrees - 170 degrees. By kinematically reversing the reactions, the recoiling of carbon, nitrogen and oxygen by 40-100 MeV 27 Al, 28 Si, 32S and 48 Ti ions into recoil angles of 20 degrees, 25 degrees, 30 degrees and 40 degrees has also been investigated. Excitation functions and angular distributions are presented. Contrary to the case of light H and He ions, the heavy ion scattering cross sections fall off rapidly above the non-Rutherford threshold energy, rendering heavy ion RBS and ERD spectrometry worthless. Both classical and wave mechanical calculations have been attempted for predicting the RBS threshold energies. Simple calculations give moderate accuracy, while the more extensive nuclear potential perturbation approach relies on parameters fitted for the particular experiment. The authors present a general classical semi-empirical model for both direct scattering (RBS) and the kinematically reversed reactions (ERD), accurately reproducing the experimental data. The model is based on parameters fitted from the present scattering experiments and from an extensive literature survey

1.4 decades of 1.4 MeV/u heavy ion beams

International Nuclear Information System (INIS)

Mokler, P.H.

1989-05-01

This report is a collection of the annual reports from 1976 to 1978 and scientific reports from 1979 to 1988 together with a list of publications and university degrees of the GSI Darmstadt. The work concerns heavy ion reactions, atomic collisions, studies of radiation effects in solids and biology, and detector development. (HSI)

Heavy ion accelerators at GSI

International Nuclear Information System (INIS)

Angert, N.

1984-01-01

The status of the Unilac heavy ion linear accelerator at GSI, Darmstadt is given. A schematic overall plan view of the Unilac is shown and its systems are described. List of isotopes and intensities accelerated at the Unilac is presented. The experimental possibilities at GSI should be considerably extended by a heavy ion synchrotron (SIS 18) in combination with an experimental storage ring (ESR). A prototype of the rf-accelerating system of the synchrotron has been built and tested. Prototypes for the quadrupole and dipole magnets for the ring are being constructed. The SIS 18 is desigmed for a maximum magnetic rigidity of 18Tm so that neon can be accelerated to 2 GeV/W and uranium to 1 GeV/u. The design allows also the acceleration of protons up to 4.5 GeV. The ESR permits to storage fully stripped uranium ions up to an energy of approximately R50 MeV/u

Dynamical limitations to heavy ion fusion

International Nuclear Information System (INIS)

Back, B.B.

1983-01-01

Dynamical limitations to heavy ion fusion reaction are considered. The experimental signatures and the importance of a quasi-fission process are examined. The anaular distributions of fission fragments for the 32 S+ 208 Pb and 16 O+ 238 U systems are presented. It is shown that the observations of quasi-fission for even rather ''light'' heavy ions poeess severe limitations on the fusion process. This result may consequently be responsible for the lack of success of the search for super heavy elements in heavy ion fusion reactions

The Shape and Flow of Heavy Ion Collisions (490th Brookhaven Lecture)

Energy Technology Data Exchange (ETDEWEB)

Schenke, Bjoern [BNL Physics Department

2014-12-18

The sun can’t do it, but colossal machines like the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab and Large Hadron Collider (LHC) in Europe sure can. Quarks and gluons make up protons and neutrons found in the nucleus of every atom in the universe. At heavy ion colliders like RHIC and the LHC, scientists can create matter more than 100,000 times hotter than the center of the sun—so hot that protons and neutrons melt into a plasma of quarks and gluons. The particle collisions and emerging quark-gluon plasma hold keys to understanding how these fundamental particles interact with each other, which helps explain how everything is held together—from atomic nuclei to human beings to the biggest stars—how all matter has mass, and what the universe looked like microseconds after the Big Bang. Dr. Schenke discusses theory that details the shape and structure of heavy ion collisions. He will also explain how this theory and data from experiments at RHIC and the LHC are being used to determine properties of the quark-gluon plasma.

Solar wind contribution to the average population of energetic He(+) and He(++) ions in the Earth's magnetosphere

Science.gov (United States)

Kremser, G.; Rasinkangas, R.; Tanskanen, P.; Wilken, B.; Gloeckler, G.

1994-01-01

Measurements with the ion charge-energy-mass spectrometer CHEM on the AMPTE/CCE spacecraft were used to investigate the origin of energetic He(+) and He(++) ions observed in the equatorial plane at 3 less than or equal to L less than or equal to 9. Special emphasis was laid on the dependence of long-term average distributions on magnetic local time (MLT) and the geomagnetic activity index K(sup p). The observations are described in terms of the phase space densities f(sub 1) (for He(+)) and f(sub 2) (for He(++)). They confirm preliminary results from a previous study f(sub 1) is independent of MLT, whereas f(sub 2) is much larger on the nightside than on the dayside. They show, furthermore, that f(sub 1) increases slightly with K(sub p) on intermediate drift shells, but decreases on high drift shells (L greater than or equal to 7). f(sub 2) increases with K(sub p) on all drift shells outside the premidnight sector. Within this sector a decrease is observed on high drift shells. A simple ion tracing code was developed to determine how and from where the ions move into the region of observations. It provides ion trajectories as a function of the ion charge, the magnetic moment and K(sub p). The ion tracing enables a distinction between regions of closed drift orbits (ring current) and open convection trajectories (plasma sheet). It also indicates how the outer part of the observation region is connected to different parts of the more distant plasma sheet. Observations and tracing show that He(++) ions are effectively transported from the plasma sheet on convection trajectories. Their distribution in the observation region corresponds to the distribution of solar wind ions in the plasma sheet. Thus, energetic He(++) ions most likely originate in the solar wind. On the other hand, the plasma sheet is not an important source of energetic He(+) ions. Convection trajectories more likely constitute a sink for He(+) ions, which may diffuse onto them from closed drift orbits

Performance test of electron cyclotron resonance ion sources for the Hyogo Ion Beam Medical Center

Science.gov (United States)

Sawada, K.; Sawada, J.; Sakata, T.; Uno, K.; Okanishi, K.; Harada, H.; Itano, A.; Higashi, A.; Akagi, T.; Yamada, S.; Noda, K.; Torikoshi, M.; Kitagawa, A.

2000-02-01

Two electron cyclotron resonance (ECR) ion sources were manufactured for the accelerator facility at the Hyogo Ion Beam Medical Center. H2+, He2+, and C4+ were chosen as the accelerating ions because they have the highest charge to mass ratio among ion states which satisfy the required intensity and quality. The sources have the same structure as the 10 GHz ECR source at the Heavy Ion Medical Accelerator in Chiba except for a few improvements in the magnetic structure. Their performance was investigated at the Sumitomo Heavy Industries factory before shipment. The maximum intensity was 1500 μA for H2+, 1320 μA for He2+, and 580 μA for C4+ at the end of the ion source beam transport line. These are several times higher than required. Sufficient performance was also observed in the flatness and long-term stability of the pulsed beams. These test results satisfy the requirements for medical use.

Interaction of He+2 ions with hydrogen molecules

International Nuclear Information System (INIS)

Afrosimov, V.V.; Leiko, G.A.; Panov, M.N.

1980-01-01

Cross sections for all elementary reactions involving a change in charge state in He +2 -H 2 collisions have been measured for He +2 kinetic energies in the range E=1.2--100 keV. Measurements were carried out by distinguishing an individual collision by a coincidence method and by simultaneously analyzing the charge states of the fast and slow particles. Furthermore, in the same event, the electronic states of the particles after the collision were determined by analyzing the kinetic energies of the resulting ions. The elementary reactions involving the formation of He + ions in the ground and excited states were studied. The reactions involving transitions in the hydrogen molecule to the 1ssigma/sub g/ and 2psigma/sub u/ states of H 2 + ions, and reactions in which wto protons are formed, were also studied. At E>15 keV, the largest cross section is that corresponding to one-electron capture: He +2 +H 2 →He + +H 2 + (this cross section is sigma=8.3 x 10 -16 cm 2 at E=50 keV). In this reaction, 90--98% of the He + ions are formed in excited states with principal quantum number n=2. At E + ion predominates, accompanied by the simultaneous dissociation of the H 2 + ion: He +2 +H 2 →He + (1s)+H + H+H0+e - . The cross section for this exothermic capture with dissociation (the energy released is ΔEapprox. =+36.3--3.8 eV) increases with decreasing energy E. At E>15 keV, an endothermic pathway is predominant: →He + (2s,2p)+H + +H+0+e - (the energy expended, ΔE, is more than 3.2 eV). The existence of two capture reactions with dissociation - exothermic and endothermic - leads to a minimum in the cross section for this reaction, at Eapprox. =15 keV. Ionization reactions and ionization with dissociation have the smallest cross sections

Auger vs resonance neutralization in low energy He+ ion scattering

International Nuclear Information System (INIS)

Woodruff, D.P.

1983-01-01

He + ions incident on a metal surface can neutralize either by an Auger or resonant charge exchange. While the Auger process has always been thought to be dominant, recent theoretical interest in the simpler one-electron resonance process has led to suggestions that this alone can account for the neutralization seen in low energy He + ion scattering. In this paper this assertion is analysed by looking at the wider information available on charge exchange processes for He + ion scattering through comparison with Li + ion scattering, the importance of multiple scattering in both these scattering experiments and the results of ion neutralization spectroscopy. These lead to the conclusion that while resonance neutralization to produce metastable He* may well occur at a substantial rate in He + ion scattering, the dominant process leading to loss of ions from the final scattered signal is Auger neutralization as originally proposed. (author)

Heavy ions

CERN Multimedia

CERN. Geneva; Antinori, Federico

2001-01-01

Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

Heavy ions

CERN Multimedia

CERN. Geneva. Audiovisual Unit

2002-01-01

Colliding two heavy nuclei at ultrarelativistic energies allows to create in the laboratory a bulk system with huge density, pressure and temperature and to study its properties. It is estimated that in Pb-Pb collisions at CERN-SPS we reach over an appreciable volume an energy density which exceeds by more than a factor 20 that of normal nuclear matter. At such densities, the hadrons are so closely packed that they interpenetrate; novel physics phenomena are expected to appear. QCD predicts that under such conditions a phase transition from a system composed of colourless hadrons to a Quark-Gluon Plasma (QGP) should occur. A rich ultrarelativistic heavy-ion physics programme is under way both at BNL-AGS and at CERN-SPS since 1986. The results obtained so far have led CERN to officially announce evidence for a new state of matter last year. A long-range programme of heavy-ion physics at higher energies is under way (BNL-RHIC) and in preparation (CERN-LHC). These lectures are meant as an introduction to the phy...

Review on heavy ion radiotherapy facilities and related ion sources (invited)

International Nuclear Information System (INIS)

Kitagawa, A.; Fujita, T.; Muramatsu, M.; Biri, S.; Drentje, A. G.

2010-01-01

Heavy ion radiotherapy awakens worldwide interest recently. The clinical results obtained by the Heavy Ion Medical Accelerator in Chiba at the National Institute of Radiological Sciences in Japan have clearly demonstrated the advantages of carbon ion radiotherapy. Presently, there are four facilities for heavy ion radiotherapy in operation, and several new facilities are under construction or being planned. The most common requests for ion sources are a long lifetime and good stability and reproducibility. Sufficient intensity has been achieved by electron cyclotron resonance ion sources at the present facilities.

International cooperation in heavy-ion research

International Nuclear Information System (INIS)

Tobias, C.A.

1980-01-01

The rapidly growing research applications of heavy ions in basic biology and medicine have stimulated interest in this field in many countries. LBL, with its unique facilities and its scientific programs, is the focal point of interest. Plans are underway in several countries, including France, Japan, West Germany, and Canada, to build heavy-ion facilities, and to collaborate with our staff at LBL in heavy-ion research in physics, biology, and medicine

Heavy ion collisions

International Nuclear Information System (INIS)

Jacak, B.V.

1994-01-01

Heavy ion collisions at very high energies provide an opportunity to recreate in the laboratory the conditions which existed very early in the universe, just after the big bang. We prepare matter at very high energy density and search for evidence that the quarks and gluons are deconfined. I describe the kinds of observables that are experimentally accessible to characterize the system and to search for evidence of new physics. A wealth of information is now available from CERN and BNL heavy ion experiments. I discuss recent results on two particle correlations, strangeness production, and dilepton and direct photon distributions

Corrosion characteristics of Hastelloy N alloy after He+ ion irradiation

International Nuclear Information System (INIS)

Lin Jianbo; Yu Xiaohan; Li Aiguo; He Shangming; Cao Xingzhong; Wang Baoyi; Li Zhuoxin

2014-01-01

With the goal of understanding the invalidation problem of irradiated Hastelloy N alloy under the condition of intense irradiation and severe corrosion, the corrosion behavior of the alloy after He + ion irradiation was investigated in molten fluoride salt at 700 °C for 500 h. The virgin samples were irradiated by 4.5 MeV He + ions at room temperature. First, the virgin and irradiated samples were studied using positron annihilation lifetime spectroscopy (PALS) to analyze the influence of irradiation dose on the vacancies. The PALS results showed that He + ion irradiation changed the size and concentration of the vacancies which seriously affected the corrosion resistance of the alloy. Second, the corroded samples were analyzed using synchrotron radiation micro-focused X-ray fluorescence, which indicated that the corrosion was mainly due to the dealloying of alloying element Cr in the matrix. Results from weight-loss measurement showed that the corrosion generally correlated with the irradiation dose of the alloy. (author)

Science and art in heavy-ion collisions

International Nuclear Information System (INIS)

Weiss, M.S.

1982-01-01

One of the more intriguing phenomena discovered in heavy-ion physics is the seeming appearance of high energy structure in the excitation spectra of inelastically scattered heavy ions. For reasons illustrated, these may well be a phenomena unique to heavy ions and their explanation perhaps unique to TDHF

Lifetime control of the minority carrier in PiN diodes by He+ ion implantation

International Nuclear Information System (INIS)

Tanaka, Y.; Kojima, K.; Takao, K.; Okamoto, M.; Kawasaki, M.; Takatsuka, A.; Yatsuo, T.; Arai, K.

2005-01-01

This paper reports the first demonstration of the lifetime control of the minority carrier in 4H-SiC PiN diodes by He + ion implantation. In this work, we fabricated 4H-SiC PiN diodes with the epitaxial junction and the blocking voltage of 2.6 kV, precisely corresponding to the theoretical blocking voltage calculated from the doping concentration (4.0 x 10 15 /cm 2 ) and the thickness of the drift layer (16.5 μm). He + ion implantation was performed with the energy and the dose of 400 kV and 1.0 x 10 13 -2.0 x 10 14 /cm 2 , respectively. We observed no different characteristics in the blocking voltage (2.6kV) and leakage current ( + ion implantation. However, we confirmed the improvement of the current recovery characteristics in the diodes with He + ion implantation. (orig.)

QCD and Heavy Ions RHIC Overview

CERN Document Server

Granier de Cassagnac, Raphael

2010-01-01

Nowadays, the most violent heavy ion collisions available to experimental study occur at the Relativistic Heavy Ion Collider (RHIC) of the Brookhaven National Laboratory. There, gold ions collide at psNN = 200 GeV. The early and most striking RHIC results were summarised in 2005 by its four experiments, BRAHMS, PHENIX, PHOBOS and STAR, in their so-called white papers [1, 2, 3, 4] that will be largely referenced thereafter. Beyond and after this, a wealth of data has been collected and analysed, providing additional information about the properties of the matter created at RHIC. It is categorically impossible to give a comprehensive review of these results in a 20 minutes talk or a 7 pages report. Here, I have made a selection of some of the most striking or intriguing signatures: jet quenching in Section 2, quarkonia suppressions in Section 3 and thermal photons in Section 4. A slightly longer and older version of this review can be found in [5]. Some updates are given here, as well as emphasis on new probes ...

Transfer products from the reactions of heavy ions with heavy nuclei

International Nuclear Information System (INIS)

Thomas, K.E. III.

1979-11-01

Production of nuclides heavier than the target from 86 Kr- and 136 Xe-induced reactions with 181 Ta and 238 U was investigated. Attempts were made to produce new neutron-excess Np and Pu isotopes by the deep inelastic mechanism. No evidence was found for 242 Np or 247 Pu. Estimates were made for the production of 242 Np, 247 Pu, and 248 Am from heavy-ion reactions with uranium targets. Comparisons of reactions of 86 Kr and 136 Xe ions with thick 181 Ta targets and 86 Kr, 136 Xe and 238 U ions with thick 238 U targets indicate that the most probable products are not dependent on the projectile. The most probable products can be predicted by the equation Z - Z/sub target/ = 0.43 (A - A/sub target/) + 1.0. The major effect of the projectile is the magnitude of the production cross section of the heavy products. Based on these results, estimates are made of the most probable mass of element 114 produced from heavy-ion reactions with 248 Cm and 254 Es targets. These estimates give the mass number of element 114 as approx. 287 if produced in heavy-ion reactions with these very heavy targets. Excitation functions of gold and bismuth isotopes arising from 86 Kr- and 136 Xe-induced reactions with thin 181 Ta targets were measured. These results indicate that the shape and location (in Z and A above the target) of the isotopic distributions are not strongly dependent on the projectile incident energy. Also, the nuclidic cross sections are found to increase with an increase in projectile energy to a maximum at approximately 1.4 to 1.5 times the Coulomb barrier. Above this maximum, the nuclidic cross sections are found to decrease with an increase in projectile energy. This decrease in cross section is believed to be due to fission of the heavy products caused by high excitation energy and angular momentum. 111 references, 39 figures, 34 tables

High-dynamic-range neutron time-of-flight detector used to infer the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yield and ion temperature on OMEGA

Energy Technology Data Exchange (ETDEWEB)

Forrest, C. J., E-mail: cforrest@lle.rochester.edu; Glebov, V. Yu.; Goncharov, V. N.; Knauer, J. P.; Radha, P. B.; Regan, S. P.; Romanofsky, M. H.; Sangster, T. C.; Shoup, M. J.; Stoeckl, C. [Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623-1299 (United States)

2016-11-15

Upgraded microchannel-plate–based photomultiplier tubes (MCP-PMT’s) with increased stability to signal-shape linearity have been implemented on the 13.4-m neutron time-of-flight (nTOF) detector at the Omega Laser Facility. This diagnostic uses oxygenated xylene doped with diphenyloxazole C{sub 15}H{sub 11}NO + p-bis-(o-methylstyryl)-benzene (PPO + bis-MSB) wavelength shifting dyes and is coupled through four viewing ports to fast-gating MCP-PMT’s, each with a different gain to allow one to measure the light output over a dynamic range of 1 × 10{sup 6}. With these enhancements, the 13.4-m nTOF can measure the D(t,n){sup 4}He and D(d,n){sup 3}He reaction yields and average ion temperatures in a single line of sight. Once calibrated for absolute neutron sensitivity, the nTOF detectors can be used to measure the neutron yield from 1 × 10{sup 9} to 1 × 10{sup 14} and the ion temperature with an accuracy approaching 5% for both the D(t,n){sup 4}He and D(d,n){sup 3}He reactions.

Acceleration of H, He, and heavy ions observed in the magnetosheath, magnetotail, and near-by interplanetary space

International Nuclear Information System (INIS)

Fan, C.Y.; Gloeckler, G.; Hovestadt, D.

1975-01-01

Pulses of electrons and ions composed of H, He, and heavier elements were observed in the magnetosheath, magnetotail, and near-by interplanetary space. From the spatial positions where these particles were detected and the ion flow directions we conclude that they were accelerated at the bow shock near the sub-solar point and in the near-earth region of the neutral sheet of the magnetotail. (orig.) [de

Heavy ion therapy: Bevalac epoch

International Nuclear Information System (INIS)

Castro, J.R.

1993-10-01

An overview of heavy ion therapy at the Bevelac complex (SuperHILac linear accelerator + Bevatron) is given. Treatment planning, clinical results with helium ions on the skull base and uveal melanoma, clinical results with high-LET charged particles, neon radiotherapy of prostate cancer, heavy charged particle irradiation for unfavorable soft tissue sarcoma, preliminary results in heavy charged particle irradiation of bone sarcoma, and irradiation of bile duct carcinoma with charged particles and-or photons are all covered

Coherent instability of the heavy ion beam in the storage ring

International Nuclear Information System (INIS)

Noda, A.

1981-01-01

The storage ring as the final part of a driver for heavy ion fusion is required to provide heavy ions (A asymptotically equals 200) with energy of 5 -- 10 GeV and such a high intensity as 1 -- 6 x 10 15 ions/pulse. So as to raise the number of ions which can be accumulated in a ring, singlly charged heavy ion is used for its relatively smaller incoherent space charge force compared with higher charge states. The intensity limit due to incoherent space charge force is 0.7 -- 1.4 x 10 15 ions for U 1 + . Much more severe limits exist due to coherent motion of heavy ion beams (0.8 -- 2 x 10 13 for longitudinal motion and 0.9 -- 1.1 x 10 12 for transverse motion), because of the relatively lower velocity of the accumulated ions. It seems unrealistic to use a lot of rings in order to operate below such intensity limits of the above instability. Therefore the number of the storage rings is constrained within a reasonable value (3 -- 7) and the possibility of compressing the bunches of heavy ion beams before the instability grows fatally large is studied. (author)

Heavy ion transfer reactions

International Nuclear Information System (INIS)

Weisser, D.C.

1977-06-01

To complement discussions on the role of γ rays in heavy ion induced reactions, the author discusses the role played by particle detection. Transfer reactions are part of this subject and are among those in which one infers the properties of the residual nucleus in a reaction by observing the emerging light nucleus. Inelastic scattering ought not be excluded from this subject, although no particles are transferred, because of the role it plays in multistep reactions and in fixing O.M. parameters describing the entrance channel of the reaction. Heavy ion transfer reaction studies have been under study for some years and yet this research is still in its infancy. The experimental techniques are difficult and the demands on theory rigorous. One of the main products of heavy ion research has been the thrust to re-examine the assumptions of reaction theory and now include many effects neglected for light ion analysis. This research has spurred the addition of multistep processes to simple direct processes and coupled channel calculations. (J.R.)

Radiation therapy using high-energy heavy-ion

International Nuclear Information System (INIS)

Kanai, Tatsuaki

1995-01-01

The clinical trial of the heavy-ion radiotherapy was started at June 1994 after pre-clinical experiments using 290 MeV/u carbon beam. In this paper, an irradiation system for the heavy-ion radiotherapy installed at HIMAC (Heavy Ion Medical Accelerator in Chiba) and the physical characteristics of the therapeutic beam were discussed. (author)

Proton and heavy ion acceleration by stochastic fluctuations in the Earth's magnetotail

Directory of Open Access Journals (Sweden)

F. Catapano

2016-10-01

Full Text Available Spacecraft observations show that energetic ions are found in the Earth's magnetotail, with energies ranging from tens of keV to a few hundreds of keV. In this paper we carry out test particle simulations in which protons and other ion species are injected in the Vlasov magnetic field configurations obtained by Catapano et al. (2015. These configurations represent solutions of a generalized Harris model, which well describes the observed profiles in the magnetotail. In addition, three-dimensional time-dependent stochastic electromagnetic perturbations are included in the simulation box, so that the ion acceleration process is studied while varying the equilibrium magnetic field profile and the ion species. We find that proton energies of the order of 100 keV are reached with simulation parameters typical of the Earth's magnetotail. By changing the ion mass and charge, we can study the acceleration of heavy ions such as He+ +  and O+, and it is found that energies of the order of 100–200 keV are reached in a few seconds for He+ + , and about 100 keV for O+.

Measurement of charge- and mass-changing cross sections for 4He+12C collisions in the energy range 80-220 MeV/u for applications in ion beam therapy

Science.gov (United States)

Horst, Felix; Schuy, Christoph; Weber, Uli; Brinkmann, Kai-Thomas; Zink, Klemens

2017-08-01

4He ions are considered to be used for hadron radiotherapy due to their favorable physical and radiobiological properties. For an accurate dose calculation the fragmentation of the primary 4He ions occurring as a result of nuclear collisions must be taken into account. Therefore precise nuclear reaction models need to be implemented in the radiation transport codes used for dose calculation. A fragmentation experiment using thin graphite targets was conducted at the Heidelberg Ion Beam Therapy Center (HIT) to obtain new and precise 4He-nucleus cross section data in the clinically relevant energy range. Measured values for the charge-changing cross section, mass-changing cross section, as well as the inclusive 3He production cross section for 4He+12C collisions at energies between 80 and 220 MeV /u are presented. These data are compared to the 4He-nucleus reaction model by DeVries and Peng as well as to the parametrizations by Tripathi et al. and by Cucinotta et al., which are implemented in the treatment planning code trip98 and several other radiation transport codes.

Therapy tumor with the heavy ions beam

International Nuclear Information System (INIS)

Dang Bingrong; Wei Zengquan; Li Wenjian

2002-01-01

As physical characteristic of heavy ions Bragg peak, therapy tumor with heavy ions is becoming advanced technology. So, many countries have developed the technology and used to treat tumor, the societal and economic effects are beneficial to people. The authors show the development, present situation and information of research in world of advanced radiotherapy with heavy ions

Towards the heavy-ion program at J-PARC

International Nuclear Information System (INIS)

Sako, H.; Chujo, T.; Gunji, T.; Harada, H.; Imai, K.; Kaneta, M.; Kinsho, M.; Liu, Y.; Nagamiya, S.; Nishio, K.; Ozawa, K.; Saha, P.K.; Sakaguchi, T.; Sato, S.; Tamura, J.

2014-01-01

A future heavy-ion program at J-PARC has been discussed. The QCD phase structure in high baryon density regime will be explored with heavy ions at the beam momenta of around 10 A GeV/c at the beam rate of 10 10 –10 11  Hz. For this quest, a large acceptance spectrometer is designed to measure electrons and muons, and rare probes such as multi-strangeness and charmed hadrons/nuclei. A heavy-ion acceleration scheme is under study with a new heavy-ion linac and a new booster ring, which accelerate and inject beams into the existing Rapid-Cycling Synchrotron and Main Ring synchrotron. An overview of the heavy-ion program and an accelerator design, as well as physics goals and a conceptual design of the heavy-ion experiment are discussed

Towards the heavy-ion program at J-PARC

Science.gov (United States)

Sako, H.; Chujo, T.; Gunji, T.; Harada, H.; Imai, K.; Kaneta, M.; Kinsho, M.; Liu, Y.; Nagamiya, S.; Nishio, K.; Ozawa, K.; Saha, P. K.; Sakaguchi, T.; Sato, S.; Tamura, J.

2014-11-01

A future heavy-ion program at J-PARC has been discussed. The QCD phase structure in high baryon density regime will be explored with heavy ions at the beam momenta of around 10 A GeV/c at the beam rate of 1010-1011 Hz. For this quest, a large acceptance spectrometer is designed to measure electrons and muons, and rare probes such as multi-strangeness and charmed hadrons/nuclei. A heavy-ion acceleration scheme is under study with a new heavy-ion linac and a new booster ring, which accelerate and inject beams into the existing Rapid-Cycling Synchrotron and Main Ring synchrotron. An overview of the heavy-ion program and an accelerator design, as well as physics goals and a conceptual design of the heavy-ion experiment are discussed.

Recoil ion spectroscopy with heavy ions

International Nuclear Information System (INIS)

Beyer, H.F.; Mann, R.

1984-01-01

This chapter examines the production of very high charge state ions in single ion-atom collisions. Topics considered include some aspects of highly ionized atoms, experimental approaches, the production of highly charged target ions (monoatomic targets, recoil energy distribution, molecular fragmentation, outer-shell rearrangement, lifetime measurements, a comparison of projectile-, target-, and plasma-ion stripping), and secondary collision experiments (selective electron capture, potential applications). The heavy-ion beams for the described experiments were provided by accelerators such as tandem Van de Graaff facility and the UNILAC

Low mass dilepton production in heavy ion collisions

International Nuclear Information System (INIS)

Pisutova, N.; Pisut, J.

1988-01-01

The total transverse energy dependence of low mass dilepton (and single low p T photon) production was demonstrated to be a signature of the onset of the evidence of plasma formation in heavy ion collisions. Cross-sections are presented for low mass dilepton production in proton-nucleus and heavy ion collisions which represent lower bounds for the ''collectivization'' and the thermalization of matter produced in the collision. Higher cross-section are a signature of the onset of the formation of thermalized matter. (author). 4 figs., 11 refs

Heavy ion collisions and cosmology

Energy Technology Data Exchange (ETDEWEB)

Floerchinger, Stefan

2016-12-15

There are interesting parallels between the physics of heavy ion collisions and cosmology. Both systems are out-of-equilibrium and relativistic fluid dynamics plays an important role for their theoretical description. From a comparison one can draw interesting conclusions for both sides. For heavy ion physics it could be rewarding to attempt a theoretical description of fluid perturbations similar to cosmological perturbation theory. In the context of late time cosmology, it could be interesting to study dissipative properties such as shear and bulk viscosity and corresponding relaxation times in more detail. Knowledge and experience from heavy ion physics could help to constrain the microscopic properties of dark matter from observational knowledge of the cosmological fluid properties.

Double-differential heavy-ion production cross sections

International Nuclear Information System (INIS)

Miller, T. M.; Townsend, L. W.

2004-01-01

Current computational tools used for space or accelerator shielding studies transport energetic heavy ions either using a one-dimensional straight-ahead approximation or by dissociating the nuclei into protons and neutrons and then performing neutron and proton transport using Monte Carlo techniques. Although the heavy secondary particles generally travel close to the beam direction, a proper treatment of the light ions produced in these reactions requires that double-differential cross sections should be utilised. Unfortunately, no fundamental nuclear model capable of serving as an event generator to provide these cross sections for all ions and energies of interest exists currently. Herein, we present a model for producing double-differential heavy-ion production cross sections that uses heavy-ion fragmentation yields produced by the NUCFRG2 fragmentation code coupled with a model of energy degradation in nucleus-nucleus collisions and systematics of momentum distributions to provide energy and angular dependences of the heavy-ion production. (authors)

Heavy quark photoproduction in ultraperipheral heavy ion collisions

International Nuclear Information System (INIS)

Klein, Spencer R.; Nystrand, Joakim; Vogt, Ramona

2002-01-01

Heavy quarks are copiously produced in ultraperipheral heavy ion collisions. In the strong electromagnetic fields, cc-bar and bb-bar are produced by photonuclear and two-photon interactions. Hadroproduction can also occur in grazing interactions. We calculate the total cross sections and the quark transverse momentum and rapidity distributions, as well as the QQ-bar invariant mass spectra from the three production channels. We consider AA and pA collisions at the Relativistic Heavy Ion Collider and the Large Hadron Collider. We discuss techniques for separating the three processes and describe how the AA to pA production ratios might be measured accurately enough to study nuclear shadowing

Basic atomic interactions of accelerated heavy ions in matter atomic interactions of heavy ions

CERN Document Server

Tolstikhina, Inga; Winckler, Nicolas; Shevelko, Viacheslav

2018-01-01

This book provides an overview of the recent experimental and theoretical results on interactions of heavy ions with gaseous, solid and plasma targets from the perspective of atomic physics. The topics discussed comprise stopping power, multiple-electron loss and capture processes, equilibrium and non-equilibrium charge-state fractions in penetration of fast ion beams through matter including relativistic domain. It also addresses mean charge-states and equilibrium target thickness in ion-beam penetrations, isotope effects in low-energy electron capture, lifetimes of heavy ion beams, semi-empirical formulae for effective cross sections. The book is intended for researchers and graduate students working in atomic, plasma and accelerator physics.

Lowest vibrational states of 4He3He+: Non-Born-Oppenheimer calculations

International Nuclear Information System (INIS)

Stanke, Monika; Bubin, Sergiy; Kedziera, Dariusz; Molski, Marcin; Adamowicz, Ludwik

2007-01-01

Very accurate quantum mechanical calculations of the first five vibrational states of the 4 He 3 He + molecular ion are reported. The calculations have been performed explicitly including the coupling of the electronic and nuclear motions [i.e., without assuming the Born-Oppenheimer (BO) approximation]. The nonrelativistic non-BO wave functions were used to calculate the α 2 relativistic mass velocity, Darwin, and spin-spin interaction corrections. For the lowest vibrational transition, whose experimental energy is established with high precision, the calculated and the experimental results differ by only 0.16 cm -1

CORONAL SOURCES, ELEMENTAL FRACTIONATION, AND RELEASE MECHANISMS OF HEAVY ION DROPOUTS IN THE SOLAR WIND

Energy Technology Data Exchange (ETDEWEB)

Weberg, Micah J. [PhD Candidate in Space Science, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2134A Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Lepri, Susan T. [Associate Professor, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2429 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States); Zurbuchen, Thomas H., E-mail: mjweberg@umich.edu, E-mail: slepri@umich.edu, E-mail: thomasz@umich.edu [Professor, Space Science and Aerospace Engineering, Associate Dean for Entrepreneurship Senior Counselor of Entrepreneurship Education, Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, 2431 Space Research Building, 2455 Hayward Street, Ann Arbor, MI 48109-2143, USA. (United States)

2015-03-10

The elemental abundances of heavy ions (masses larger than He) in the solar wind provide information about physical processes occurring in the corona. Additionally, the charge state distributions of these heavy ions are sensitive to the temperature profiles of their respective source regions in the corona. Heavy ion dropouts are a relatively new class of solar wind events identified by both elemental and ionic charge state distributions. We have shown that their origins lie in large, closed coronal loops where processes such as gravitational settling dominate and can cause a mass-dependent fractionation pattern. In this study we consider and attempt to answer three fundamental questions concerning heavy ion dropouts: (1) 'where are the source loops located in the large-scale corona?'; (2) 'how does the interplay between coronal processes influence the end elemental abundances?'; and (3) 'what are the most probable release mechanisms'? We begin by analyzing the temporal and spatial variability of heavy ion dropouts and their correlation with heliospheric plasma and magnetic structures. Next we investigate the ordering of the elements inside dropouts with respect to mass, ionic charge state, and first ionization potential. Finally, we discuss these results in the context of the prevailing solar wind theories and the processes they posit that may be responsible for the release of coronal plasma into interplanetary space.

CORONAL SOURCES, ELEMENTAL FRACTIONATION, AND RELEASE MECHANISMS OF HEAVY ION DROPOUTS IN THE SOLAR WIND

International Nuclear Information System (INIS)

Weberg, Micah J.; Lepri, Susan T.; Zurbuchen, Thomas H.

2015-01-01

The elemental abundances of heavy ions (masses larger than He) in the solar wind provide information about physical processes occurring in the corona. Additionally, the charge state distributions of these heavy ions are sensitive to the temperature profiles of their respective source regions in the corona. Heavy ion dropouts are a relatively new class of solar wind events identified by both elemental and ionic charge state distributions. We have shown that their origins lie in large, closed coronal loops where processes such as gravitational settling dominate and can cause a mass-dependent fractionation pattern. In this study we consider and attempt to answer three fundamental questions concerning heavy ion dropouts: (1) 'where are the source loops located in the large-scale corona?'; (2) 'how does the interplay between coronal processes influence the end elemental abundances?'; and (3) 'what are the most probable release mechanisms'? We begin by analyzing the temporal and spatial variability of heavy ion dropouts and their correlation with heliospheric plasma and magnetic structures. Next we investigate the ordering of the elements inside dropouts with respect to mass, ionic charge state, and first ionization potential. Finally, we discuss these results in the context of the prevailing solar wind theories and the processes they posit that may be responsible for the release of coronal plasma into interplanetary space

Heavy-ion mammography and breast cancer

International Nuclear Information System (INIS)

Fabrikant, J.I.; Tobias, C.A.; Capp, M.P.; Holley, W.R.; Woodruff, K.H.; Sickles, E.A.

1980-01-01

Heavy-ion radiography is a new diagnostic imaging technique developed in our laboratory that produces superior density resolution at low radiation doses. Heavy-ion mammography has now emerged as a low-dose, safe, reliable, noninvasive diagnostic radiological procedure that can quantitate and image very small differences in soft tissue densities in the breast tissues of patients with clinical breast disease. The improved density resolution of heavy-ion mammography over conventional X-ray mammography and breast xerography provides the potential of detecting small breast cancers of less than 1 cm diameter. The radiation dose to the breast from carbon-ion mammorgraphy is about 50 mrad or less, and can potentially be only a fraction of this level. The results of the present clinical trial in progress of heavy-ion mammography in 37 patients, thus far studied, are extremely encouraging, and warrant continued study for application to the early diagnosis of breast cancer in women

High Accuracy, High Energy He-Erd Analysis of H,C, and T

International Nuclear Information System (INIS)

Browning, James F.; Langley, Robert A.; Doyle, Barney L.; Banks, James C.; Wampler, William R.

1999-01-01

A new analysis technique using high-energy helium ions for the simultaneous elastic recoil detection of all three hydrogen isotopes in metal hydride systems extending to depths of several microm's is presented. Analysis shows that it is possible to separate each hydrogen isotope in a heavy matrix such as erbium to depths of 5 microm using incident 11.48MeV 4 He 2 ions with a detection system composed of a range foil and ΔE-E telescope detector. Newly measured cross sections for the elastic recoil scattering of 4 He 2 ions from protons and deuterons are presented in the energy range 10 to 11.75 MeV for the laboratory recoil angle of 30degree

Towards the heavy-ion program at J-PARC

Energy Technology Data Exchange (ETDEWEB)

Sako, H. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); J-PARC Center, Japan Atomic Energy Agency, Tokay, Naka, Ibaraki 319-1195 (Japan); Chujo, T. [University of Tsukuba, Tsukuba, Ibaraki 305-8577 (Japan); Gunji, T. [Center for Nuclear Study, University of Tokyo, Wako, Saitama 351-0198 (Japan); Harada, H. [J-PARC Center, Japan Atomic Energy Agency, Tokay, Naka, Ibaraki 319-1195 (Japan); Imai, K. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Kaneta, M. [Tohoku University, Sendai, Miyagi 980-8578 (Japan); Kinsho, M. [J-PARC Center, Japan Atomic Energy Agency, Tokay, Naka, Ibaraki 319-1195 (Japan); Liu, Y. [J-PARC Center, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Nagamiya, S. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); RIKEN, Wako, Saitama 351-0198 (Japan); J-PARC Center, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Nishio, K. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Ozawa, K. [J-PARC Center, High Energy Accelerator Research Organization, Tsukuba, Ibaraki 305-0801 (Japan); Saha, P.K. [J-PARC Center, Japan Atomic Energy Agency, Tokay, Naka, Ibaraki 319-1195 (Japan); Sakaguchi, T. [Broohaven National Laboratory, Upton, NY 11973-5000 (United States); Sato, S. [Advanced Science Research Center, Japan Atomic Energy Agency, Tokai, Naka, Ibaraki 319-1195 (Japan); Tamura, J. [J-PARC Center, Japan Atomic Energy Agency, Tokay, Naka, Ibaraki 319-1195 (Japan)

2014-11-15

A future heavy-ion program at J-PARC has been discussed. The QCD phase structure in high baryon density regime will be explored with heavy ions at the beam momenta of around 10 A GeV/c at the beam rate of 10{sup 10}–10{sup 11} Hz. For this quest, a large acceptance spectrometer is designed to measure electrons and muons, and rare probes such as multi-strangeness and charmed hadrons/nuclei. A heavy-ion acceleration scheme is under study with a new heavy-ion linac and a new booster ring, which accelerate and inject beams into the existing Rapid-Cycling Synchrotron and Main Ring synchrotron. An overview of the heavy-ion program and an accelerator design, as well as physics goals and a conceptual design of the heavy-ion experiment are discussed.

X-ray emission in heavy-ion collisions. Progress report, April 1, 1980-February 28, 1981

International Nuclear Information System (INIS)

Watson, R.L.

1981-03-01

During the past year, work on x-ray emission in heavy-ion collisions has concentrated on the following topics: environmental influences on the Kα x-ray spectra of 65-MeV sulfur ions traveling in solids; multiplet structure of few-electron sulfur ions; multiplet structure of Mg Kα x-ray satellites; polarization of 1s2p→1s 2 transitions in He-like sulfur ions; and interatomic electron transfer in ionic fluorine compounds following 1s2p vacancy production. Among the most significant accomplishments of the program was a study of the dependence of dynamic screening energy shifts on electron density. It was found that the shifts measured for the 2 1 P→1 1 S and 2 2 P→1 2 S x-ray transitions of He- and H-like sulfur ions (respectively) were in remarkably good agreement with theoretical expectations. Another interesting discovery evolved from measurements of fluorine Kα x-ray spectra for the alkali metal and alkaline earth fluorides using 5.5-MeV He + ions. The systematics of these spectra provide the first evidence for direct electron transfer between inner levels of neighboring atoms in a solid. 10 figures, 3 tables

Heavy-ion radiography applied to charged particle radiotherapy

International Nuclear Information System (INIS)

Chen, G.T.Y.; Fabrikant, J.I.; Holley, W.R.; Tobias, C.A.; Castro, J.R.

1980-01-01

The objectives of the heavy-ion radiography research program applied to the clinical cancer research program of charged particle radiotherapy have a twofold purpose: (1) to explore the manner in which heavy-ion radiography and CT reconstruction can provide improved tumor localization, treatment planning, and beam delivery for radiotherapy with accelerated heavy charged particles; and (2) to explore the usefulness of heavy-ion radiography in detecting, localizing, and sizing soft tissue cancers in the human body. The techniques and procedures developed for heavy-ion radiography should prove successful in support of charged particle radiotherapy

Atomic x-ray production by relativistic heavy ions

International Nuclear Information System (INIS)

Ioannou, J.G.

1977-12-01

The interaction of heavy ion projectiles with the electrons of target atoms gives rise to the production, in the target, of K-, L- or higher shell vacancies which are in turn followed by the emission of characteristic x-rays. The calculation of the theoretical value of the K- and L-shells vacancy production cross section was carried out for heavy ion projectiles of any energy. The transverse component of the cross section is calculated for the first time in detail and extensive tables of its numerical value as a function of its parameters are also given. Experimental work for 4.88 GeV protons and 3 GeV carbon ions is described. The K vacancy cross section has been measured for a variety of targets from Ti to U. The agreement between the theoretical predictions and experimental results for the 4.88 GeV protons is rather satisfactory. For the 3 GeV carbon ions, however, it is observed that the deviation of the theoretical and experimental values of the K vacancy production becomes larger with the heavier target element. Consequently, the simple scaling law of Z 1 2 for the cross section of the heavy ion with atomic number Z 1 to the proton cross section is not true, for the K-shell at least. A dependence on the atomic number Z 2 of the target of the form (Z 1 - αZ 2 ) 2 , instead of Z 1 2 , is found to give extremely good agreement between theory and experiment. Although the exact physical meaning of such dependence is not yet clearly understood, it is believed to be indicative of some sort of screening effect of the incoming fast projectile by the fast moving in Bohr orbits K-shell electrons of the target. The enhancement of the K-shell ionization cross section by relativistic heavy ions on heavy targets is also discussed in terms of its practical applications in various branches of science and technology

Target design for heavy ion beam fusion

International Nuclear Information System (INIS)

Meyer-ter-Vehn, J.; Metzler, N.

1981-07-01

Target design for Heavy Ion Beam Fusion and related physics are discussed. First, a modified version of the Kidder-Bodner model for pellet gain is presented and is used to define the working point (Esub(beam) = 4.8 MJ, Gain 83) for a reactor size target. Secondly, stopping of heavy ions in hot dense plasma is investigated and numerical results for stopping powers and ranges of 10 GeV Bi-ions in Pb, Li, and PbLi-alloy are given. Finally, results of an explicit implosion calculation, using the 1-D code MINIHY, are discussed in detail. The hydrodynamic efficiency is found to be about 5%. Special attention is given to the shock sequence leading to the ignition configuration. Also the growth of Rayleigh-Taylor instability at the absorber-pusher interface is estimated. (orig.)

Heavy metal incorporated helium ion active hybrid non-chemically amplified resists: Nano-patterning with low line edge roughness

Directory of Open Access Journals (Sweden)

Pulikanti Guruprasad Reddy

2017-08-01

Full Text Available Helium (He ion lithography is being considered as one of the most promising and emerging technology for the manufacturing of next generation integrated circuits (ICs at nanolevel. However, He-ion active resists are rarely reported. In this context, we are introducing a new non-chemically amplified hybrid resist (n-CAR, MAPDSA-MAPDST, for high resolution He-ion beam lithography (HBL applications. In the resist architecture, 2.15 % antimony is incorporated as heavy metal in the form of antimonate. This newly developed resists has successfully used for patterning 20 nm negative tone features at a dose of 60 μC/cm2. The resist offered very low line edge roughness (1.27±0.31 nm for 20 nm line features. To our knowledge, this is the first He-ion active hybrid resist for nanopatterning. The contrast (γ and sensitivity (E0 of this resist were calculated from the contrast curve as 0.73 and 7.2 μC/cm2, respectively.

Heavy metal incorporated helium ion active hybrid non-chemically amplified resists: Nano-patterning with low line edge roughness

Science.gov (United States)

Reddy, Pulikanti Guruprasad; Thakur, Neha; Lee, Chien-Lin; Chien, Sheng-Wei; Pradeep, Chullikkattil P.; Ghosh, Subrata; Tsai, Kuen-Yu; Gonsalves, Kenneth E.

2017-08-01

Helium (He) ion lithography is being considered as one of the most promising and emerging technology for the manufacturing of next generation integrated circuits (ICs) at nanolevel. However, He-ion active resists are rarely reported. In this context, we are introducing a new non-chemically amplified hybrid resist (n-CAR), MAPDSA-MAPDST, for high resolution He-ion beam lithography (HBL) applications. In the resist architecture, 2.15 % antimony is incorporated as heavy metal in the form of antimonate. This newly developed resists has successfully used for patterning 20 nm negative tone features at a dose of 60 μC/cm2. The resist offered very low line edge roughness (1.27±0.31 nm) for 20 nm line features. To our knowledge, this is the first He-ion active hybrid resist for nanopatterning. The contrast (γ) and sensitivity (E0) of this resist were calculated from the contrast curve as 0.73 and 7.2 μC/cm2, respectively.

Swift Heavy Ions in Matter

Science.gov (United States)

Rothard, Hermann; Severin, Daniel; Trautmann, Christina

2015-12-01

The present volume contains the proceedings of the Ninth International Symposium on Swift Heavy Ions in Matter (SHIM). This conference was held in Darmstadt, from 18 to 21 May 2015. SHIM is a triennial series, which started about 25 years ago by a joint initiative of CIRIL - Caen and GSI - Darmstadt, with the aim of promoting fundamental and applied interdisciplinary research in the field of high-energy, heavy-ion interaction processes with matter. SHIM was successively organized in Caen (1989), Bensheim (1992), Caen (1995), Berlin (1998), Catania (2002), Aschaffenburg (2005), Lyon (2008), and Kyoto (2012). The conference attracts scientists from many different fields using high-energy heavy ions delivered by large accelerator facilities and characterized by strong and short electronic excitations.

Relativistic heavy ion reactions

Energy Technology Data Exchange (ETDEWEB)

Brink, D M

1989-08-01

The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs.

Relativistic heavy ion reactions

International Nuclear Information System (INIS)

Brink, D.M.

1989-08-01

The theory of quantum chromodynamics predicts that if nuclear matter is heated to a sufficiently high temperature then quarks might become deconfined and a quark-gluon plasma could be produced. One of the aims of relativistic heavy ion experiments is to search for this new state of matter. These lectures survey some of the new experimental results and give an introduction to the theories used to interpret them. 48 refs., 4 tabs., 11 figs

For high energy heavy ion experiments TPC 4π detector 'Diogene'. What possibilities and what physics

International Nuclear Information System (INIS)

Babinet, R.; Cassagnou, Y.; Drouet, M.

1981-05-01

'Diogene' is the name of a 4π solid angle detector, based on a Time Projection Chamber (TPC), designed to perform exclusive measurements of charged particles emitted in central collisions of relativistic heavy ions. Exclusive measurements of all charged particles emitted in central collisions of relativistic heavy ions are becoming more and more necessary in this field of nuclear physics in order to answer some crucial questions such as: what is the degree of compression achieved in these collisions. What is the behavior of nuclear matter at high degree of excitation as well as compression. The possibility of handling high multiplicities up to 40 or 60; a momentum measurement of all particles, with not too bad a resolution, up to about 1.5 GeV/c; a good particle identification between π +- , p, d, t ..

Study of charge symmetry in 4He by simultaneous 4He(e,e'p)3H and 4He(e,e'n)3He measurements

International Nuclear Information System (INIS)

Spahn, M.; Kihm, T.; Knopfle, K.T.; Friedrich, J.; Voegler, N.; Schmitt, C.; Walther, V.H.; Unkelbach, M.; Hofmann, H.M.

1989-01-01

We have measured the ( 3 H+p) and ( 3 He+n) breakup of 4 He by 4 He(e,e'c) coincidence experiments at low momentum transfer (q∼0.39 fm -1 ) in the excitation energy region 22≤E x ≤36 MeV. Both channels were studied simultaneously by detecting the charged fragments c=p, 3 H, and 3 He in the same detector system. The measured 4 He(e,e'p) 3 H and 4 He(e,e'n) 3 He angular correlations as well as the deduced total 4 He(e,e'p) 3 H and 4 He(e,e'n) 3 He cross sections are reproduced by microscopic model calculations with a charge-symmetric nuclear Hamiltonian

Cyclotron method for heavy ion acceleration

International Nuclear Information System (INIS)

Gikal, B.N.; Gul'bekyan, G.G.; Kutner, V.B.; Oganesyan, R.Ts.

1984-01-01

Studies on heavy ion beams in a wide range of masses (up to uranium) and energies disclose essential potential opportunities for solution of both fundamental scientific and significant economical problems. A cyclotron method for heavy ion acceleration is considered. Development of low and medium energy heavy ion accelerators is revealed. The design of a complex comprising two isochronous cyclotrons which is planned to be constrdcted 1n the JINR is described. The cyclotron complex includes the U-400 and the U-400 M cyclotrons and it is intended for acceleration of both 35-20 MeV/nucleon superheavy ions such as Xe-U and 120 MeV/nucleon light ions. Certain systems of the accelerators are described. Prospects of the U-400 and the U-400 M development are displayed

Funny hills in pion spectra from heavy-ion collisions

International Nuclear Information System (INIS)

Rasmussen, J.O.

1982-03-01

A discussion of some of the systematic features of the pion spectra in heavy-ions reactions is given. A discussion of the hills and valleys in heavy ion pion spectra that show up at the lower pion energies is given. The following topics are discussed: (1) three kinds of funny hills; (2) π - / + ratios near center of mass; (3) new Monte Carlo studies of charged pion spectra; and (4) pion orbiting about fireballs and Bose-Einstein behavior as explanation for the mid-rapidity P/sub perpendicular to/ approx. = 0.4 to 0.5 m/sub π/c hill

HIGH DENSITY QCD WITH HEAVY-IONS

CERN Multimedia

The Addendum 1 to Volume 2 of the CMS Physics TDR has been published The Heavy-Ion analysis group completed the writing of a TDR summarizing the CMS plans in using heavy ion collisions to study high density QCD. The document was submitted to the LHCC in March and presented in the Open Session of the LHCC on May 9th. The study of heavy-ion physics at the LHC is promising to be very exciting. LHC will open a new energy frontier in ultra-relativistic heavy-ion physics. The collision energy of heavy nuclei at sNN = 5.5 TeV will be thirty times larger than what is presently available at RHIC. We will certainly probe quark and gluon matter at unprecedented values of energy density. The prime goal of this research programme is to study the fundamental theory of the strong interaction - Quantum Chromodynamics (QCD) - in extreme conditions of temperature, density and parton momentum fraction (low-x). Such studies, with impressive experimental and theoretical advances in recent years thanks to the wealth of high-qua...

Construction of Rb charge exchange cell and characteristic experiment for He- ion production

International Nuclear Information System (INIS)

Lee, Hee Seock; Bak, Jun Gyo; Bak, Hae Ill

1991-01-01

The Rb charge exchange cell is constructed as the He - ion source of the SNU 1.5-MV Tandem Van de Graaff accelerator. the characteristic experiments is carried out in order to determine the optimum operational conditions of the cell. The He + ion beam with the energy of 1 - 10 keV, extracted from the duoplasmatron ion source, is passed through the Rb vapor to become He - ions by the two step charge exchange reaction, i.e., He + + Rb → He o* + Rb + and He o* + Rb → He - + Rb + . From the experimental results, it is found that the maximum fractional yield of He - ions is produced at He + /ion energy of 7 keV. The optimum temperatures of the oven and the canal are determined to be 370 deg C and 95 deg C respectively. Under the optimum operational condition the maximum fractional yield of He - ions is 2.42 ± 0.02 5. This charge exchange cell is proved to be an effective system for the production of He - ions. (Author)

Giant resonances in heavy-ion reactions

International Nuclear Information System (INIS)

Hussein, M.S.

1982-11-01

The several roles of multipole giant resonances in heavy-ion reactions are discussed. In particular, the modifications in the effective ion-ion potencial due to the virtual excitation of giant resonances at low energies, are considered and estimated for several systems. Real excitation of giant resonances in heavy-ion reactions at intermediate energies are then discussed and their importance in the approach phase of deeply inelastic processes in emphasized. Several demonstrative examples are given. (Author) [pt

Implantation of 111In in NTDSi by heavy ion recoil technique

International Nuclear Information System (INIS)

Thakare, S.V.; Tomar, B.S.

1998-01-01

Heavy ion recoil implantation technique has been used to implant 111 In in n-type silicon using medium energy heavy ion accelerator Pelletron, at TIFR, Colaba, Mumbai. The nuclear reaction used for this purpose was 109 Ag( 7 Li,p4n) 111 In. The beam energy was optimised to be 50 MeV for maximum concentration of the implanted probe atoms. The gamma-ray spectrum of the implanted sample after 24 hours was found to contain only 171 and 245 keV gamma rays of 111 In. The penetration depth of ion is increased to 1.6 μm by heavy ion recoil implantation technique as compared to 0.16 μm with the conventional ion implantation technique. (author)

Heavy Ion Irradiation Effects in Zirconium Nitride

International Nuclear Information System (INIS)

Egeland, G.W.; Bond, G.M.; Valdez, J.A.; Swadener, J.G.; McClellan, K.J.; Maloy, S.A.; Sickafus, K.E.; Oliver, B.

2004-01-01

Polycrystalline zirconium nitride (ZrN) samples were irradiated with He + , Kr ++ , and Xe ++ ions to high (>1.10 16 ions/cm 2 ) fluences at ∼100 K. Following ion irradiation, transmission electron microscopy (TEM) and grazing incidence X-ray diffraction (GIXRD) were used to analyze the microstructure and crystal structure of the post-irradiated material. For ion doses equivalent to approximately 200 displacements per atom (dpa), ZrN was found to resist any amorphization transformation, based on TEM observations. At very high displacement damage doses, GIXRD measurements revealed tetragonal splitting of some of the diffraction maxima (maxima which are associated with cubic ZrN prior to irradiation). In addition to TEM and GIXRD, mechanical property changes were characterized using nano-indentation. Nano-indentation revealed no change in elastic modulus of ZrN with increasing ion dose, while the hardness of the irradiated ZrN was found to increase significantly with ion dose. Finally, He + ion implanted ZrN samples were annealed to examine He gas retention properties of ZrN as a function of annealing temperature. He gas release was measured using a residual gas analysis (RGA) spectrometer. RGA measurements were performed on He-implanted ZrN samples and on ZrN samples that had also been irradiated with Xe ++ ions, in order to introduce high levels of displacive radiation damage into the matrix. He evolution studies revealed that ZrN samples with high levels of displacement damage due to Xe implantation, show a lower temperature threshold for He release than do pristine ZrN samples. (authors)

Heavy-ion radiation chemistry

International Nuclear Information System (INIS)

Imamura, Masashi

1975-01-01

New aspect of heavy ion radiation chemistry is reviewed. Experiment has been carried out with carbon ions and nitrogen ions accelerated by a 160 cm cyclotron of the Institute of Physical and Chemical Research. The results of experiments are discussed, taking into consideration the effects of core radius depending on heavy ion energy and of the branch tracks of secondary electrons outside the core on chemical reaction and the yield of products. The effect of core size on chemical reaction was not able to be observed, because the incident energy of heavy ions was only several tens of MeV. Regarding high radical density, attention must be given to the production of oxygen in the core. It is possible to produce O 2 in the core in case of high linear energy transfer (LET), while no production of O 2 in case of low LET radiation. This may be one of study problems in future. LET effects on the yield of decomposed products were examined on acetone, methyl-ethyl-ketone and diethyl ketone, using heavy ions (C and N) as well as gamma radiation and helium ions. These three ketones showed that the LET change of two gaseous products, H 2 and CO, was THF type. There are peaks at 50-70 eV/A in the yield of both products. The peaks suggest the occurrence of ''saturation'' in decomposition. Attention was drawn to acetone containing a small amount (2 wt.%) of H 2 O. H 2 O and CO produced from this system differ from those in the pure system. The hydrogen connection formed by such a small amount of H 2 O may mediate the energy transfer. Sodium acetate tri-hydrate produces CH 3 radical selectively by gamma-ray irradiation at 77 K. In this case, the production of CH 2 COO - increases with the increase of LET of radiation. This phenomenon may be an important study problem. (Iwakiri, K.)

Quantum beats study of the 4He+ beam-carbon foil interaction

International Nuclear Information System (INIS)

Denis, A.; Desesquelles, J.

1979-01-01

Excitation cross-sections are deduced from the analysis of quantum beats in an electric field for an 4 He + (n=4) ion beam scattering through a thin carbon foil. The population distribution obtained at 1 MeV for 4S, 4P, 4D and 4F levels is in good agreement with a second-order Born approximation calculation of the electronic capture He ++ +C→He + (n=4) + C + . The alignment is found to be negative for P, D and F levels. The coherences Δl=+-1 have been measured, for amplitudes and phases [fr

A high charge state heavy ion beam source for heavy ion fusion

International Nuclear Information System (INIS)

Eylon, S.; Henestroza, E.

1996-01-01

A high current, low emittance, high charge state heavy ion beam source is being developed. This is designed to deliver a heavy ion fusion (HIF) driver accelerator scale beam. Using a high charge state beam in a driver accelerator for HIF may increase the acceleration efficiency, leading to a reduction in the driver accelerator size and cost. The proposed source system, which consists of a gas beam electron stripper followed by a high charge state beam separator, can be added to existing single charge state, low emittance, high brightness ion sources and injectors. We shall report on the source physics design using 3D beam simulations and experimental feasibility study results using a neutral gas stripper and a beam separator at the exit of the LBL 2 MV injector. (orig.)

Relativistic heavy ion research at Berkeley

International Nuclear Information System (INIS)

Anon.

1981-01-01

The project of a superconducting synchrotron for heavy ions with 1 TeV/amu is described. In this connection the physics is discussed which can be studied by this accelerator. Furthermore, the HISS-heavy ion spectrometer system and the Plastic Ball detector are described. (HSI).

Electron-impact ionization of heavy atomic ions

International Nuclear Information System (INIS)

Pindzola, M.S.; Griffin, D.C.; Bottcher, C.

1987-01-01

General theoretical methods for the calculation of direct and indirect processes in the electron-impact ionization of heavy atomic ions are reviewed. Cross section results for Xe 8+ and U 89+ are presented. 12 refs., 4 figs

ESR investigation of L-α-alanine and sucrose radicals produced by heavy-ion irradiation

International Nuclear Information System (INIS)

Nakagawa, K.; Sato, Y.

2005-01-01

We investigated sucrose and L-α-alanine radicals produced by heavy (particle) ion irradiation with various LETs (linear energy transfer). The impact of the heavy ions on the samples produced stable free radicals, which were analyzed by ESR (electron spin resonance). Identical spectra were measured after one year. The obtained spectral patterns were the same as those for helium (He), carbon (C), and neon (Ne) ions irradiation. The absorbed dose dependences for the irradiated sucrose and alanine samples were examined. The ESR response has a linear relation with the absorbed dose. The ESR response at 60 Gy was slightly lower than a linear line for sucrose; however, the response showed good linearity for the alanine. In addition, the total spin concentration obtained by heavy-ion irradiation correlated logarithmically with the LET. Qualitative ESR analyse showed that the production of sucrose and alanine radicals depended on both different particle irradiation and the LET under the same dose. Thus, the present ESR results imply that sucrose together with L-α-alanine can be used to monitor LET as well as the number of ionizing particle for the production of stable free radicals. (author)

Graphene nanoribbon superlattices fabricated via He ion lithography

International Nuclear Information System (INIS)

Archanjo, Braulio S.; Fragneaud, Benjamin; Gustavo Cançado, Luiz; Winston, Donald; Miao, Feng; Alberto Achete, Carlos; Medeiros-Ribeiro, Gilberto

2014-01-01

Single-step nano-lithography was performed on graphene sheets using a helium ion microscope. Parallel “defect” lines of ∼1 μm length and ≈5 nm width were written to form nanoribbon gratings down to 20 nm pitch. Polarized Raman spectroscopy shows that crystallographic orientation of the nanoribbons was partially maintained at their lateral edges, indicating a high-fidelity lithography process. Furthermore, Raman analysis of large exposure areas with different ion doses reveals that He ions produce point defects with radii ∼ 2× smaller than do Ga ions, demonstrating that scanning-He + -beam lithography can texture graphene with less damage

Graphene nanoribbon superlattices fabricated via He ion lithography

Energy Technology Data Exchange (ETDEWEB)

Archanjo, Braulio S., E-mail: bsarchanjo@inmetro.gov.br [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Fragneaud, Benjamin [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Física, Universidade Federal de Juiz de Fora, Juiz de Fora, MG 36036-330 (Brazil); Gustavo Cançado, Luiz [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 30123-970 (Brazil); Winston, Donald [Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States); Miao, Feng [Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States); National Laboratory of Solid State Microstructures, School of Physics, National Center of Microstructures and Quantum Manipulation, Nanjing University, Nanjing 210093 (China); Alberto Achete, Carlos [Divisão de Metrologia de Materiais, Instituto Nacional de Metrologia, Qualidade e Tecnologia (INMETRO), Duque de Caxias, RJ 25250-020 (Brazil); Departamento de Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de janeiro, Rio de Janeiro RJ 21941-972 (Brazil); Medeiros-Ribeiro, Gilberto [Departamento de Física, Universidade Federal de Minas Gerais, Belo Horizonte, MG 30123-970 (Brazil); Hewlett-Packard Laboratories, 1501 Page Mill Road, Palo Alto, California 94304 (United States)

2014-05-12

Single-step nano-lithography was performed on graphene sheets using a helium ion microscope. Parallel “defect” lines of ∼1 μm length and ≈5 nm width were written to form nanoribbon gratings down to 20 nm pitch. Polarized Raman spectroscopy shows that crystallographic orientation of the nanoribbons was partially maintained at their lateral edges, indicating a high-fidelity lithography process. Furthermore, Raman analysis of large exposure areas with different ion doses reveals that He ions produce point defects with radii ∼ 2× smaller than do Ga ions, demonstrating that scanning-He{sup +}-beam lithography can texture graphene with less damage.

Adsorption of heavy metal ions on different clays

International Nuclear Information System (INIS)

Kruse, K.

1992-01-01

The aim of the present dissertation is to study the adsorption of heavy metal ions (Cd 2+ , Cu 2+ , Pb 2+ , Zn 2+ ) and their mixtures on clays. Different clays and bentonites (Ca 2+ -bentonite, activated Na + -bentonite, special heavy metal adsorber bentonite, two organophilic bentonites and a mixed layer clay) were used. The adsorbed metal ions were desorbed by appropriate solutions of HCl, EDTA and dioctadecyl dimethylammonium bromide. High concentrations of the heavy metal ions in the solutions can be reached. The desorption guarantees economical recycling. After desorption the clays were used (up to three times) for purification of contaminated water. The best experimental conditions, i.e. the highest adsorption of heavy metal ions from aqueous solutions was found for the greatest ratio of adsorbent/adsorbate. The adsorption was very fast. Calcium, sodium bentonites and the heavy metal adsorber bentonite attained the highest adsorption and desorption for Cu 2+, Zn 2+ and Pb 2+ ions. Cd 2+ ions were only absorbed by Silitonit, a special heavy metal absorber bentonite. The mixed layer clay (Opalit) ranges in adsorption and desorption properties below the unmodified Ca 2+ -bentonite (Montigel) or the activated Na + -bentonite. Only Tixosorb and Tixogel (organophilic bentonites) reach the lowest value of heavy metal adsorption. Only lead cations which are characterised by good polarizability were adsorbed at higher rates, therefore the organophilic bentonites are not appropriate for adsorption of heavy metal ions from aqueous solutions. Mixing of the metal ions generally decreases the adsorption of Pb 2+ and increases the adsorption of Cd 2+ . From mixtures if heavy metal ions adsorption and desorption of Cu 2+ ions reached a maximum for all clays. (author) figs., tabs., 56 refs

Adsorption of heavy metal ions by activated charcoal

International Nuclear Information System (INIS)

Fujikawa, Mitsuo

1978-01-01

The adsorption effect was measured for several kinds of heavy metal ions, Pb 2+ , Cd 2+ , Cu 2+ and Zn 2+ by passing them through activated charcoal beds and changing the pH values of solutions. The test procedure is to keep the pH value of solution more than 10 at first, filter heavy metal hydroxide deposit, measure the remaining ion concentration in filtrate, and also test the influence of the addition of alkali to each kind of ions. The individual test procedure for each kind of ions is explained. As for the Cd ions, after the detailed experimental procedure is explained, the adsorption characteristic line is shown as the relation between the adsorption quantity and the equilibrium concentration of Cd 2+ . The similar test procedure and the adsorption characteristic lines are shown and evaluated about Pb 2+ , Cu 2+ and Zn 2+ . These lines are all linear, but have different adsorption quantity and inclination in relation to heavy metal ion concentration. Concerning the influence of pH to adsorption, the characteristics of pH increase are presented, when alkali is added by various quantities to Zn 2+ , Cu 2+ , Pb 2+ and Cd 2+ . The pH of Pb 2+ increased to about 10 by adding 0.4 cc alkali and saturates, but the pH of the other ions did not saturate by adding less than 1.5 cc alkali. When the water containing heavy metals are treated, Cd 2+ , Pb 2+ , Cu 2+ and Zn 2+ are removed almost satisfactorily by passing them through active charcoal filters and keeping pH at 10. The experimental concentrations are 0.05 ppm at pH 10 in Cd, 0.86 ppm at 10.3 in Pb, 0 ppm at pH 9.6 in Cu, 0.06 ppm at pH 8.8 and 12.4 ppm at pH 9.8 in Zn. (Nakai, Y.)

The mobility of negative ions in superfluid 3He

International Nuclear Information System (INIS)

Solomaa, M.

1982-01-01

This article reviews recent experimental and theoretical work on the mobility of negative ions in the superfluid A and B phases of liquid 3 He. In the normal Fermi liquid at temperatures below approximately 50 mK and also in the superfluid close to the superfluid transition temperature, Tsub(c), the mobility of a negative ion may simply be considered as limited by the elastic scattering of 3 He quasiparticles. This explains the constancy of the ion mobility in the normal phase. However, underlying the rapid increase of the measured mobility in the superfluid phases there is a subtle quantum-mechanical scattering effect. Detailed solutions of the 3 He quasiparticle-negative ion scattering process in the pair-correlated state provide a simple physical picture of an energy-dependent forward-peaking phenomenon. This yields quantitative theoretical results for the ion mobility in the quasi-isotropic B phase and for the ion mobility tensor in the anisotropic A phase which agree with the experimental data. (author)

Transverse emittance studies of an induction accelerator of heavy ions

International Nuclear Information System (INIS)

Garvey, T.; Eylon, S.; Fessenden, T.J.; Hahn, K.; Henestroza, E.

1991-01-01

Current amplification of heavy ion beams is an integral feature of the induction linac approach to heavy ion fusion. As part of the Heavy Ion Fusion Accelerator Research program at LBL the authors have been studying the evolution of the transverse emittance of ion beams while they are undergoing current amplification, achieved by longitudinal bunch compression and acceleration. Experiments are conducted on MBE-4, a four beam Cs + induction linac. The space-charge dominated beams of MBE-4 are focused by electrostatic quadrupoles while they are accelerated from nominally 200 keV up to ∼ 1 MEV by 24 accelerating gaps. Initially the beams have currents of typically 4 mA to 10 mA per beam. Early experimental results showed a growth of the normalized emittance by a factor of 2 while the beam current was amplified by up to 9 times its initial value. The authors will discuss the results of recent experiments in which a mild bunch length compression rate, more typical of that required by a fusion driver, has shown that the normalized emittance can be maintained at its injection value (0.03 mm-mr) during acceleration

The threshold anomaly for heavy-ion scattering

Energy Technology Data Exchange (ETDEWEB)

Satchler, G.R.

1987-01-01

The real parts of optical potentials deduced from heavy-ion scattering measurements become rapidly more attractive as the bombarding energy is reduced close to the top of the Coulomb barrier. This behavior is explained as a coupled-channels effect, and is related to the corresponding reduction in the absorptive potential through a dispersion relation which expresses the consequences of causality. Another manifestation of this ''anomaly'' is the striking enhancement observed for the near- and sub-barrier fusion of two heavy ions. The barrier penetration model of fusion is examined critically in this context. It is also stressed that similar anomalies could appear in the energy dependence of nonelastic scattering. 21 refs., 4 figs.

Heavy ions: Report from Relativistic Heavy Ion Collider

Indian Academy of Sciences (India)

2012-10-12

Oct 12, 2012 ... Experiments using ultrarelativistic heavy-ion collisions study nuclear matter under ... sN N = 10 GeV for Pb+Pb collisions, corresponding to an initial .... quenching through systematic comparisons of data to models, and .... the RdAu and RCP = (0−20%)/(60−80%) factors for the J/ψ production in d+Au col-.

Heavy-ion performance of the LHC and future colliders

CERN Document Server

AUTHOR|(SzGeCERN)696614; Stahl, Achim; Jowett, John M

2015-10-09

In 2008 the Large Hadron Collider (LHC) and its experiments started operation at the European Centre of Nuclear Research (CERN) in Geneva with the main aim of finding or excluding the Higgs boson. Only four years later, on the 4th of July 2012, the discovery of a Higgs-like particle was proven and first published by the two main experiments ATLAS and CMS. Even though proton–proton collisions are the main operation mode of the LHC, it also acts as an heavy-ion collider. Here, the term “heavy-ion collisions” refers to the collision between fully stripped nuclei. While the major hardware system of the LHC is compatible with heavy-ion operation, the beam dynamics and performance limits of ion beams are quite different from those of protons. Because of the higher mass and charge of the ions, beam dynamic effects like intra-beam scattering and radiation damping are stronger. Also the electromagnetic cross-sections in the collisions are larger, leading to significantly faster intensity decay and thus shorter l...

Interaction of ions, atoms, and small molecules with quantized vortex lines in superfluid (4)He.

Science.gov (United States)

Mateo, David; Eloranta, Jussi; Williams, Gary A

2015-02-14

The interaction of a number of impurities (H2, Ag, Cu, Ag2, Cu2, Li, He3 (+), He(*) ((3)S), He2 (∗) ((3)Σu), and e(-)) with quantized rectilinear vortex lines in superfluid (4)He is calculated by using the Orsay-Trento density functional theory (DFT) method at 0 K. The Donnelly-Parks (DP) potential function binding ions to the vortex is combined with DFT data, yielding the impurity radius as well as the vortex line core parameter. The vortex core parameter at 0 K (0.74 Å) obtained either directly from the vortex line geometry or through the DP potential fitting is smaller than previously suggested but is compatible with the value obtained from re-analysis of the Rayfield-Reif experiment. All of the impurities have significantly higher binding energies to vortex lines below 1 K than the available thermal energy, where the thermally assisted escape process becomes exponentially negligible. Even at higher temperatures 1.5-2.0 K, the trapping times for larger metal clusters are sufficiently long that the previously observed metal nanowire assembly in superfluid helium can take place at vortex lines. The binding energy of the electron bubble is predicted to decrease as a function of both temperature and pressure, which allows adjusting the trap depth for either permanent trapping or to allow thermally assisted escape. Finally, a new scheme for determining the trapping of impurities on vortex lines by optical absorption spectroscopy is outlined and demonstrated for He(*).

Nuclear fission induced by heavy ions

International Nuclear Information System (INIS)

Newton, J.O.

1988-09-01

Because the accelerators of the 50's and 60's mostly provided beams of light ions, well suited for studying individual quantum states of low angular momentum or reactions involving the transfer of one or two nucleons, the study of fission, being an example of large-scale collective motion, has until recently been outside of the mainstream of nuclear research. This situation has changed in recent years, due to the new generation of accelerators capable of producing beams of heavy ions with energies high enough to overcome the Coulomb barriers of all stable nuclei. These have made possible the study of new examples of large-scale collective motions, involving major rearrangements of nuclear matter, such as deep-inelastic collisions and heavy-ion fusion. Perhaps the most exciting development in the past few years is the discovery that dissipative effects (nuclear viscosity) play an important role in fission induced by heavy ions, contrary to earlier assumptions that the viscosity involved in fission was very weak and played only a minor role. This review will be mainly concerned with developments in heavy-ion induced fission during the last few years and have an emphasis on the very recent results on dissipative effects. Since heavy-ion bombardment usually results in compound systems with high excitation energies and angular momenta, shell effects might be expected to be small, and the subject of low energy fission, where they are important, will not be addressed. 285 refs., 58 figs

Solar wind contribution to the average population of energetic He+ and He++ ions in the Earth's magnetosphere

Directory of Open Access Journals (Sweden)

G. Kremser

Full Text Available Measurements with the ion charge-energy-mass spectrometer CHEM on the AMPTE/CCE spacecraft were used to investigate the origin of energetic He⁺ and He⁺⁺ ions observed in the equatorial plane at 3 ≤ L ≤ 9. Special emphasis was laid on the dependence of long-term average distributions on magnetic local time (MLT and the geomagnetic activity index K_p. The observations are described in terms of the phase space densities f₁ (for He⁺ and f₂ (for He⁺⁺. They confirm preliminary results from a previous study: f₁ is independent of MLT, whereas f₂ is much larger on the nightside than on the dayside. They show, furthermore, that f₁ increases slightly with K_p on intermediate drift shells, but decreases on high drift shells (L ≥ 7. f₂ increases with K_p on all drift shells outside the premidnight sector. Within this sector a decrease is observed on high drift shells. A simple ion tracing code was developed to determine how and from where the ions move into the region of observations. It provides ion trajectories as a function of the ion charge, the magnetic moment and K_p. The ion tracing enables a distinction between regions of closed drift orbits (ring current and open convection trajectories (plasma sheet. It also indicates how the outer part of the observation region is connected to different parts of the more distant plasma sheet. Observations and tracing show that He⁺⁺ ions are effectively transported from the plasma sheet on convection trajectories. Their distribution in the observation region corresponds to the distribution of solar wind ions in the plasma sheet. Thus, energetic He⁺⁺ ions most likely originate in the solar wind. On the other hand, the plasma sheet is not an

Summary of the relativistic heavy ion sessions

International Nuclear Information System (INIS)

Harris, J.W.

1988-01-01

The topics covered in the Relativistic Heavy Ion Sessions span four orders of magnitude in energy in the laboratory and a few more in theory. In the two years since the last Intersections conference, experiments in the field of very high energy heavy ion research have begun at CERN and Brookhaven. The prime motivation for these experiments is the possibility of forming quark matter. This paper is a review of the topics covered in the Relativistic Heavy Ion Sessions

Improvement of highly charged ion production in the ECR source of heavy ions

International Nuclear Information System (INIS)

Shirkov, G.D.

1996-01-01

Some physical limitations of the highly charged ion production in the ECR source are analyzed in this report. A few possible ways to improve the output of highly charged ions from the ECR source for heavy ions are proposed. A new library of computer codes for the numerical simulation of heavy ion production in the ECR ion source is used to examine these ways to improve the ECR source operation according to the CERN program of heavy ion acceleration. copyright 1996 American Institute of Physics

Observation of the antimatter partner of Rutherford's α-particle - 4He-bar

International Nuclear Information System (INIS)

Tang, Aihong

2012-01-01

The antimatter helium-4 nucleus ( 4 He-bar, or anti-α) has not been observed previously although the α-particle was identified a century ago by Rutherford. High-energy nuclear collisions recreate energy densities similar to that of the universe microseconds after the Big Bang, and in both cases, matter and antimatter are created with comparable abundances. However, the relatively short-lived expansion in nuclear collisions makes it possible for antimatter to decouple quickly from matter. This makes a high-energy accelerator facility the ideal environment for producing and studying antimatter. In this paper, we report 18 antihelium-4 nuclei discovered by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). The measured invariant differential cross section is consistent with expectation from thermodynamics and coalescent nucleosynthesis models, which has implications for future production of even heavier antimatter nuclei, as well as for experimental searches for new phenomena in the cosmos. Future directions of rare and exotic matter searches from STAR will also be discussed.

Production of highly ionized recoil ions in heavy ion impact

International Nuclear Information System (INIS)

Tawara, H.; Tonuma, T.; Be, S.H.; Shibata, H.; Kase, M.; Kambara, T.; Kumagai, H.; Kohno, I.

1985-01-01

The production mechanisms of highly ionized recoil ions in energetic, highly charged heavy ion impact are compared with those in photon and electron impact. In addition to the innershell ionization processes which are important in photon and electron impact, the electron transfer processes are found to play a key role in heavy ion impact. In molecular targets are also observed highly ionized monoatomic ions which are believed to be produced through production of highly ionized molecular ions followed by prompt dissociation. The observed N 6+ ions produced in 1.05MeV/amu Ar 12+ ions on N 2 molecules are produced through, for example, N 2 12+ *→N 6+ +N 6+ process. (author)

Heavy-ion-driven electronuclear process

International Nuclear Information System (INIS)

Barashenkov, V.S.; Sosnin, A.N.; Filinova, V.P.

1996-01-01

Results of Monte Carlo mathematical experiments with electronuclear process in uranium and thorium homo- and heterogeneous targets irradiated by protons and heavy ions are presented. It is shown that neutron yield is the highest while using the deuteron beam and sharply decreases in case of heavier projectiles. Time dependent non-linear effects stipulated by an accumulation of fissile nuclides are discussed. 8 refs., 4 figs., 3 tab

Particle and heavy ion transport code system; PHITS

International Nuclear Information System (INIS)

Niita, Koji

2004-01-01

Intermediate and high energy nuclear data are strongly required in design study of many facilities such as accelerator-driven systems, intense pulse spallation neutron sources, and also in medical and space technology. There is, however, few evaluated nuclear data of intermediate and high energy nuclear reactions. Therefore, we have to use some models or systematics for the cross sections, which are essential ingredients of high energy particle and heavy ion transport code to estimate neutron yield, heat deposition and many other quantities of the transport phenomena in materials. We have developed general purpose particle and heavy ion transport Monte Carlo code system, PHITS (Particle and Heavy Ion Transport code System), based on the NMTC/JAM code by the collaboration of Tohoku University, JAERI and RIST. The PHITS has three important ingredients which enable us to calculate (1) high energy nuclear reactions up to 200 GeV, (2) heavy ion collision and its transport in material, (3) low energy neutron transport based on the evaluated nuclear data. In the PHITS, the cross sections of high energy nuclear reactions are obtained by JAM model. JAM (Jet AA Microscopic Transport Model) is a hadronic cascade model, which explicitly treats all established hadronic states including resonances and all hadron-hadron cross sections parametrized based on the resonance model and string model by fitting the available experimental data. The PHITS can describe the transport of heavy ions and their collisions by making use of JQMD and SPAR code. The JQMD (JAERI Quantum Molecular Dynamics) is a simulation code for nucleus nucleus collisions based on the molecular dynamics. The SPAR code is widely used to calculate the stopping powers and ranges for charged particles and heavy ions. The PHITS has included some part of MCNP4C code, by which the transport of low energy neutron, photon and electron based on the evaluated nuclear data can be described. Furthermore, the high energy nuclear

Detector issues for relativistic heavy ion experimentation

International Nuclear Information System (INIS)

Gordon, H.

1986-04-01

Several aspects of experiments using relativistic heavy ion beams are discussed. The problems that the current generation of light ion experiments would face in using gold beams are noted. A brief review of colliding beam experiments for heavy ion beams is contrasted with requirements for SSC detectors. 11 refs., 13 figs

[Relativistic heavy ion research

International Nuclear Information System (INIS)

1990-01-01

At Brookhaven National Laboratory, participation in the E802 Experiment, which is the first major heavy-ion experiment at the BNL-AGS, was the main focus of the group during the past four years. The emphases of the E802 experiment were on (a) accurate particle identification and measurements of spectra over a wide kinematical domain (5 degree LAB < 55 degree, p < 20 GeV/c); and (b) measurements of small-angle two-particle correlations, with event characterization tools: multiplicity array, forward and large-angle calorimeters. This experiment and other heavy ion collision experiments are discussed in this report

Heavy Ion Physics at LHC

CERN Document Server

Valenti, G.

2002-01-01

The study of heavy ion interactions constitutes an important part of the experimental program outlined for the Large Hadron Collider under construction at CERN and expected to be operational by 2006. ALICE 1 is the single detector having the capabilities to explore at the same time most of the characteristics of high energy heavy ion interactions. Specific studies of jet quenching and quarkonia production, essentially related to µ detection are also planned by CMS 2 .

Stopping power for heavy ions in low energy region

International Nuclear Information System (INIS)

Kitagawa, Mitsuo

1983-01-01

Review is made for the study on the power for stopping heavy ions. The studies on the power for stopping heavy ions passing through materials have been developed in the last twenty years due to the accuracy improvement in the data analysis of the power for stopping light ions, the requirement of data establishment on the power for stopping heavy ions from fusion research and the development of the experimental studies by heavy-ion accelerators. The relation between the analysis of the power for stopping heavy ions and the power for stopping light ions is described from the standpoint that the results on the power for stopping light ions serve as the guide for the study on the power for stopping heavy ions. Both at present and in future. The analysis of stopping power data with the accuracy from +-10 to 20 % is possible from the theoretical analysis of effective electric charge and its systematic table of the numerical data. The outline of the scaling rule on effective electric charge is discussed. The deviation of the experimental data from the scaling rule is discussed by comparing with the measured values of effective electric charge ratio. Various analyses of the power for stopping heavy ions are summarized. (Asami, T.)

Development of heavy-ion accelerators as drivers for inertially confined fusion

International Nuclear Information System (INIS)

Herrmannsfeldt, W.B.

1979-06-01

The commercialization of inertial confinement fusion is discussed in terms of power costs. A chapter on heavy ion accelerators covers the prinicpal components, beam loss mechanisms, and theoretical considerations. Other tyopics discussed include the following: (1) heavy ion fusion implementation plan, (2) driver with accumulator rings fed by an rf LINAC, (3) single pass driver with an induction LINAC, and (4) implementation scenarios

Study on possibility of development of a laser multicharged ion source for a heavy ion fusion driver

International Nuclear Information System (INIS)

Barabash, L.Z.; Krechet, K.I.; Lapitskij, Yu.Ya.; Latyshev, S.V.; Shumshurov, A.V.

1983-01-01

The results of studying laser produced plasma ion sources for a heavy ion accelerating-storage complex used as a heavy ion fusion driver are presented. The following parameters were measured on an installation aimed for studying physical characteristics of heavy ion laser plasma for a lead target at laser radiation flux density of approximately 3x10 10 W/cm 2 : scattered ion charge composition, energy spectra and scattering angle distributions, ion currents, absolute number of ions in every charge state, plasma electron temperature. The ion current pulse duration varied from 3x10 -4 s at Z +1 to 2x10 -5 s at Z +10 . The maximum current amplitude of 2 mA corresponded to Z +7 charge. The scattering velocity increased with charge. The total number of ions that could be used for acceleration was approximately 5x10 13 for Z +2 and 5x10 12 for Z +6 per pulse. The ion laser source brightness was 2x10 11 A/cm 2 , the particle phase density was 10 18 (cmxrad) -1

HISTRAP proposal: heavy-ion storage ring for atomic physics

Energy Technology Data Exchange (ETDEWEB)

Olsen, D K; Alton, G D; Datz, S; Dittner, P F; Dowling, D T; Haynes, D L; Hudson, E D; Johnson, J W; Lee, I Y; Lord, R S

1987-04-01

HISTRAP, Heavy-Ion Storage Ring for Atomic Physics, is a proposed 46.8-m-circumference synchrotron-cooling-storage ring optimized to accelerate, decelerate, and store beams of highly charge very-heavy ions at energies appropriate for advanced atomic physics research. The ring is designed to allow studies of electron-ion, photon-ion, ion-atom, and ion-ion interactions. An electron cooling system will provide ion beams with small angular divergence and energy spread for precision spectroscopic studies and also is necessary to allow the deceleration of heavy ions to low energies. HISTRAP will have a maximum bending power of 2.0 T m and will be injected with ions from either the existing Holifield Heavy Ion Research Facility 25-MV tandem accelerator or from a dedicated ECR source and 250 keV/nucleon RFQ linac.

Attractive well of He--He from 3He--4He differential elastic scattering measurements

International Nuclear Information System (INIS)

Burgmans, A.L.J.; Farrar, J.M.; Lee, Y.T.

1976-01-01

The elastic differential cross section for 3 He-- 4 He was measured at a relative collision energy of 0.799x10 -14 erg, approximately five times the well depth. The data are fitted to a multiparameter potential form with epsilon/k=10.57 degreeK and r/subm/=2.97 A. Comparisons with recent experimental and theoretical helium potentials are made. No evidence for a significant isotope effect in the 3 He-- 4 He and 4 He-- 4 He interactomic potentials is found in this work

Plasma focus as an heavy ion source in the problem of heavy ion fusion

International Nuclear Information System (INIS)

Gribkov, V.A.; Dubrovskij, A.V.; Kalachev, N.V.; Krokhin, O.N.; Silin, P.V.; Nikulin, V.Ya.; Cheblukov, Yu.N.

1984-01-01

Results of experiments on the ion flux formation in a plasma focus (PF) to develop a multicharged ion source for thermonuclear facility driver are presented. In plasma focus accelerating section copper ions were injected. Advantages of the suggested method of ion beam formation are demonstrated. Beam emittance equalling < 0.1 cmxmrad is obtained. Plasma focus ion energy exceeds 1 MeV. Plasma focus in combination with a neodymium laser is thought to be a perspective ion source for heavy ion fusion

Heavy ion reactions at high energies

International Nuclear Information System (INIS)

Jakobsson, Bo.

1977-01-01

A review on heavy ion experiments at energies >0.1GeV/nucleon is presented. Reaction cross-sections, isotope production cross-sections and pion production in nucleus-nucleus collisions are discussed. Some recent models for heavy ion reactions like the abrasion-ablation model, the fireball model and the different shock-wave models are also presented

Cellular radiobiology of heavy-ion beams

International Nuclear Information System (INIS)

Tobias, C.A.; Blakely, E.A.; Ngo, F.Q.H.; Roots, R.J.; Yang, T.C.

1981-01-01

Progress is reported in the following areas of this research program: relative biological effectiveness and oxygen enhancement ratio of silicon ion beams; heavy ion effects on the cell cycle; the potentiation effect (2 doses of high LET heavy-ion radiations separated by 2 to 3 hours); potentially lethal damage in actively growing cells and plateau growth cells; radiation induced macromolecular lesions and cellular radiation chemistry; lethal effects of dual radiation; and the development of a biophysical repair/misrepair model

Heavy-ion-linac post-accelerators

International Nuclear Information System (INIS)

Bollinger, L.M.

1979-01-01

The main features of the tandem-linac system for heavy-ion acceleration are reviewed and illustrated in terms of the technology and performance of the superconducting heavy-ion energy booster at Argonne. This technology is compared briefly with the corresponding technologies of the superconducting linac at Stony Brook and the room-temperature linac at Heidelberg. The performance possibilities for the near-term future are illustrated in terms of the proposed extension of the Argonne booster to form ATLAS

Dimerization of 3He in 3He-4He mixture films

International Nuclear Information System (INIS)

Bashkin, E.

1994-01-01

3 He atoms dissolved in superfluid 4 He may form dimers ( 3 He) 2 in two-dimensional geometries. Dimer formation is studied in films of dilute 3 He- 4 He mixture. After designing a schematic 3 He- 3 He interaction potential, the dimer binding energy is calculated for various substrates. It is shown that 3 He impurity states localized near the substrate give rise to the highest magnitudes of the binding energy. (author). 32 refs., 6 figs.,; 1 tab

Bound states of 3He in 3He-4He mixture films

International Nuclear Information System (INIS)

Bashkin, E.; Pavloff, N.; Treiner, J.

1995-01-01

3 He atoms dissolved in superfluid 4 He may form dimers ( 3 He) 2 in two-dimensional (2D) geometries. We study dimer formation in films of dilute 3 He- 4 He mixture. After designing a schematic 3 He- 4 He interaction potential we calculate the dimer binding energy for various substrates. It is shown that 3 He impurity states localized near the substrate give rise to the largest magnitudes of the binding energies

Neutral hydrogen from the foil-induced dissociation of 4HeH+, 3HeH+, and H2+

International Nuclear Information System (INIS)

Cooney, P.J.; Gemmell, D.S.; Kanter, E.P.; Pietsch, W.J.; Zabransky, B.J.

1979-01-01

High resolution energy spectra and angular distributions of H 0 from the dissociation of 4 HeH + , 3 HeH + , and H 2 + in thin carbon foils are presented for incident ion energies ranging from 170 to 1800 keV/amu. For the range of dwell times inside the target foils studied (about 1 to 10 fsec), the dominant mechanism for such dissociation is the Coulomb explosion of the ions inside the target followed by electron capture near the rear surface of the foil. At the shortest of these dwell times, the yield of H 0 for incident ions oriented perpendicular to the beam relative to that for ions aligned with the beam is a factor of two greater than at longer dwell times. These data indicate that, for ion fragments which emerge from the rear surface of the target within a few angstroms of one another, those in the perpendicular orientation have a greater electron capture probability than those emerging in other orientations. 9 references

Energy-loss of He ions in carbon allotropes studied by elastic resonance in backscattering spectra

Energy Technology Data Exchange (ETDEWEB)

Tosaki, Mitsuo, E-mail: tosaki.mitsuo.3v@kyoto-u.ac.jp [Radioisotope Research Center, Kyoto University, Kyoto 606-8501 (Japan); Rauhala, Eero [Department of Physics, University of Helsinki (Finland)

2015-10-01

Backscattering spectra for {sup 4}He ions incident on carbon allotropes have been measured in the energy range from 4.30 to 4.95 MeV in steps of 50–100 keV at scattering angles of 106° and 170°. We used three carbon allotropes: graphite, diamond and amorphous carbon. For all these allotropes, we can observe the sharp ({sup 4}He, {sup 12}C) elastic nuclear resonance at the He ion energy of 4.265 MeV in the backscattering spectra. By varying the incident He energy, we have systematically analyzed the profiles of the resonance peaks to study the energy-loss processes: stopping cross-sections and energy-loss straggling around the interesting region of the stopping maximum at about 500 keV. We focus on the resonance profiles and investigate an allotropic effect concerning the energy-loss. Furthermore, an energy bunching effect on the straggling is presented and the mechanism is discussed.

A study of effective atomic numbers and electron densities of some vitamins for electron, H, He and C ion interactions

Science.gov (United States)

Büyükyıldız, M.

2017-09-01

The radiological properties of some vitamins such as Retinol, Beta-carotene, Riboflavin, Niacin, Niacinamide, Pantothenic acid, Pyridoxine, Pyridoxamine, Pyridoxal, Biotin, Folic acid, Ascorbic acid, Cholecalciferol, Alpha-tocopherol, Gamma-tocopherol, Phylloquinone have been investigated with respect to total electron interaction and some heavy charged particle interaction as means of effective atomic numbers (Z_{eff}) and electron densities (N_{eff}) for the first time. Calculations were performed for total electron interaction and heavy ions such as H, He and C ion interactions in the energy region 10keV-10MeV by using a logarithmic interpolation method. Variations in Z_{eff}'s and N_{eff}'s of given vitamins have been studied according to the energy of electron or heavy charged particles, and significant variations have been observed for all types of interaction in the given energy region. The maximum values of Z_{eff} have been found in the different energy regions for different interactions remarkably and variations in N_{eff} seem approximately to be the same with variation in Z_{eff} for the given vitamins as expected. Z_{eff} values of some vitamins were plotted together and compared with each other for electron, H, He and C interactions and the ratios of Z_{eff}/ have been changed in the range of 0.25-0.36, 0.20-0.36, 0.22-0.35 and 0.20-0.35 for electron, H, He and C interactions, respectively.

Surface damage versus defect microstructures in He and H ion co-implanted Si{sub 3}N{sub 4}/Si

Energy Technology Data Exchange (ETDEWEB)

Zhu, F. [School of Science, Tianjin University, Tianjin 300072 (China); Liu, C.L., E-mail: liuchanglong@tju.edu.cn [School of Science, Tianjin University, Tianjin 300072 (China); Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, Institute of Advanced Materials Physics Faculty of Science, Tianjin 300072 (China); Gao, Y.J.; Wang, Z.; Wang, J. [School of Science, Tianjin University, Tianjin 300072 (China)

2012-09-01

Cz n-type Si (1 0 0) wafers with a top Si{sub 3}N{sub 4} layer of about 170 nm in thickness were sequentially implanted with 40 keV He ions at a fluence of 5 Multiplication-Sign 10{sup 16}/cm{sup 2} and 35 keV H ions at fluences of 1 Multiplication-Sign 10{sup 15}, 5 Multiplication-Sign 10{sup 15} and 1 Multiplication-Sign 10{sup 16}/cm{sup 2}, respectively. Creation and evolution of surface damage as well as micro-defects have been studied. Our results clearly show that production of surface damage depends strongly on both the H implant fluence and annealing temperature. Only blistering or localized exfoliation of the top Si{sub 3}N{sub 4} layer has been observed for post H implantation at fluences of 1 Multiplication-Sign 10{sup 15} and 5 Multiplication-Sign 10{sup 15}/cm{sup 2} upon 800 Degree-Sign C annealing. However, serious surface exfoliation has been found for the 1 Multiplication-Sign 10{sup 16}/cm{sup 2} H co-implanted samples after annealing at 450 Degree-Sign C and above. The exfoliation occurs at a depth of about 360 nm from the surface, which is obviously larger than the He or H ion range. Moreover, the exfoliated craters show clear two-step structures. Cross-sectional transmission electron microscopy (XTEM) observations reveal formation of micro-cracks in Si bulk and along the original interface, which is mainly responsible for the observed surface phenomena. The formation mechanism of micro-cracks has been discussed in combination of He and H implant-induced defects, impurities as well as their interactions upon annealing.

Phenomenological approaches of dissipative heavy ion collisions

International Nuclear Information System (INIS)

Ngo, C.

1983-09-01

These lectures describe the properties of dissipative heavy ion collisions observed in low bombarding energy heavy ion reactions. These dissipative collisions are of two different types: fusion and deep inelastic reactions. Their main experimental properties are described on selected examples. It is shown how it is possible to give a simple interpretation to the data. A large number of phenomenological models have been developped to understand dissipative heavy ion collisions. The most important are those describing the collision by classical mechanics and friction forces, the diffusion models, and transport theories which merge both preceding approaches. A special emphasis has been done on two phenomena observed in dissipative heavy ion collisions: charge equilibratium for which we can show the existence of quantum fluctuations, and fast fission which appears as an intermediate mechanism between deep inelastic reactions and compound nucleus formation [fr

Heavy-ion performance of the LHC and future colliders

Energy Technology Data Exchange (ETDEWEB)

Schaumann, Michaela

2015-04-29

In 2008 the Large Hadron Collider (LHC) and its experiments started operation at the European Centre of Nuclear Research (CERN) in Geneva with the main aim of finding or excluding the Higgs boson. Only four years later, on the 4th of July 2012, the discovery of a Higgs-like particle was proven and first published by the two main experiments ATLAS and CMS. Even though proton-proton collisions are the main operation mode of the LHC, it also acts as an heavy-ion collider. Here, the term ''heavy-ion collisions'' refers to the collision between fully stripped nuclei. While the major hardware system of the LHC is compatible with heavy-ion operation, the beam dynamics and performance limits of ion beams are quite different from those of protons. Because of the higher mass and charge of the ions, beam dynamic effects like intra-beam scattering and radiation damping are stronger. Also the electromagnetic cross-sections in the collisions are larger, leading to significantly faster intensity decay and thus shorter luminosity lifetimes. As the production cross-sections for various physics processes under study of the experiments are still small at energies reachable with the LHC and because the heavy-ion run time is limited to a few days per year, it is essential to obtain the highest possible collision rate, i.e. maximise the instantaneous luminosity, in order to obtain enough events and therefore low statistical errors. Within this thesis, the past performance of the LHC in lead-lead (Pb-Pb) collisions, at a centre-of-mass energy of 2.76 TeV per colliding nucleon pair, is analysed and potential luminosity limitations are identified. Tools are developed to predict future performance and techniques are presented to further increase the luminosity. Finally, a perspective on the future of high energy heavy-ion colliders is given.

Observation of the Rotational Spectra of 4HeH+, 4HeD+, 3HeH+, and 3HeD+

International Nuclear Information System (INIS)

Matsushima, F.; Oka, T.; Takagi, K.

1997-01-01

Low J rotational transitions of 4 HeH + , 4 HeD + , 3 HeH + , and 3 HeD + were observed in the 2 endash 5THz region with a high-precision far-infrared spectrometer. Dunham coefficients Y kl and isotopically independent parameters U kl , Δ He kl , and Δ H kl were determined. In particular, Δ parameters with k=0 and l=1,2 were determined with unprecedented accuracy, and provide important information for breakdown of the Born-Oppenheimer approximation. The lowest J=1 left-arrow 0 transition of 4 HeH + observed at 2010.1839(2)GHz will be an important future probe for detecting this species in space. copyright 1997 The American Physical Society

Production of strange clusters in relativistic heavy ion collisions

International Nuclear Information System (INIS)

Dover, C.B.; Baltz, A.J.; Pang, Yang; Schlagel, T.J.; Kahana, S.H.

1993-02-01

We address a number of issues related to the production of strangeness in high energy heavy ion collisions, including the possibility that stable states of multi-strange hyperonic or quark matter might exist, and the prospects that such objects may be created and detected in the laboratory. We make use of events generated by the cascade code ARC to estimate the rapidity distribution dN/dy of strange clusters produced in Si+Au and Au+Au collisions at AGS energies. These calculations are performed in a simple coalescence model, which yields a consistent description of the strange cluster (d, 3 HE, 3 H, 4 He) production at these energies. If a doubly strange, weakly bound ΛΛ dibaryon exists, we find that it is produced rather copiously in Au+Au collisions, with dN/dy ∼0.1 at raid-rapidity. If one adds another non-strange or strange baryon to a cluster, the production rate decreases by roughly one or two orders of magnitude, respectively. For instance, we predict that the hypernucleus ΛΛ 6 He should have dN/dy ∼5 x 10 -6 for Au+Au central collisions. It should be possible to measure the successive Λ → pπ- weak decays of this object. We comment on the possibility that conventional multi-strange hypernuclei may serve as ''doorway states'' for the production of stable configurations of strange quark matter, if such states exist

Proton and heavy ion acceleration by stochastic fluctuations in the Earth's magnetotail

Energy Technology Data Exchange (ETDEWEB)

Catapano, Filomena; Zimbardo, Gaetano; Perri, Silvia; Greco, Antonella [Calabria Univ., Rende (Italy). Dept. of Physics; Artemyev, Anton V. [Russian Academy of Science, Moscow (Russian Federation). Space Research Inst.; California Univ., Los Angeles, CA (United States). Dept. of Earth, Planetary, and Space Science and Inst. of Geophysics and Planetary Physics

2016-07-01

Spacecraft observations show that energetic ions are found in the Earth's magnetotail, with energies ranging from tens of keV to a few hundreds of keV. In this paper we carry out test particle simulations in which protons and other ion species are injected in the Vlasov magnetic field configurations obtained by Catapano et al. (2015). These configurations represent solutions of a generalized Harris model, which well describes the observed profiles in the magnetotail. In addition, three-dimensional time-dependent stochastic electromagnetic perturbations are included in the simulation box, so that the ion acceleration process is studied while varying the equilibrium magnetic field profile and the ion species. We find that proton energies of the order of 100 keV are reached with simulation parameters typical of the Earth's magnetotail. By changing the ion mass and charge, we can study the acceleration of heavy ions such as He{sup ++} and O{sup +}, and it is found that energies of the order of 100-200 keV are reached in a few seconds for He{sup ++}, and about 100 keV for O{sup +}.

Prototype inverted sputter source for negative heavy ions

International Nuclear Information System (INIS)

Minehara, Eisuke; Kobayashi, Chiaki; Kikuchi, Shiroh

1977-10-01

A sputter source from which negative heavy ion beam is extracted through a tungsten wire and disc ionizer was built and tested. An alkali metal surface ionization gun with the ionizer is described, and also performance of the surface ionization gun and of the sputter source for negative heavy ions using the gun is reported. The gun was tested for three alkali metals, i.e. sodium, potassium and cesium. Total potassium beam current of 1-2mA was obtained at entrance aperture of the magnet. Sputtering materials and gases for producing negative heavy ions are carbon, copper, aluminium, molybdenum, oxygen and air. With carbon and leakage air, the beam intensities analyzed are: 2-5μA (at Faraday cup) and 4.6-11μA (at exit slit) for C - , 3-5μA (at Faraday cup) and 6.8-11μA (at exit slit) for 2C - , and 11-15μA (at Faraday cup) and 25-34μA (at exit slit) for O - . Total beam current at the entrance aperture was 200-400μA. (auth.)

BNL heavy ion fusion program

International Nuclear Information System (INIS)

Maschke, A.W.

1978-01-01

A principal attraction of heavy ion fusion is that existing accelerator technology and theory are sufficiently advanced to allow one to commence the design of a machine capable of igniting thermonuclear explosions. There are, however, a number of features which are not found in existing accelerators built for other purposes. The main thrust of the BNL Heavy Ion Fusion program has been to explore these features. Longitudinal beam bunching, very low velocity acceleration, and space charge neutralization are briefly discussed

Ion sources for heavy ion fusion

International Nuclear Information System (INIS)

Yu, S.S.; Eylon, S.; Chupp, W.

1995-09-01

The development of ion sources for heavy ion fusion will be reported with particular emphasis on a recently built 2 MV injector. The new injector is based on an electrostatic quadrupole configuration, and has produced pulsed K + ions of 950 mA peak from a 6.7 inch curved alumino silicate source. The ion beam has reached 2.3 MV with an energy flatness of ±0.2% over 1 micros. The measured normalized edge emittance of less than 1 π mm-mr is close to the source temperature limit. The design, construction, performance, and comparisons with three-dimensional particle-in-cell simulations will be described

Heavy ion irradiation effects of polymer film on absorption of light

Energy Technology Data Exchange (ETDEWEB)

Kasai, Noboru; Seguchi, Tadao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Arakawa, Tetsuhito

1997-03-01

Ion irradiation effects on the absorption of light for three types of polymer films; polyethylene-terephthalate (PET), polyethylene-naphthalate (PEN), and polyether-ether-ketone (PEEK) were investigated by irradiation of heavy ions with Ni{sup 4+}(15MeV), O{sup 6+}(160MeV), and Ar{sup 8+}(175MeV), and compared with electron beams(EB) irradiation. The change of absorption at 400nm by a photometer was almost proportional to total dose for ions and EB. The absorption per absorbed dose was much high in Ni{sup 4+}, but rather small in O{sup 6+} and Ar{sup 8+} irradiation, and the absorption by EB irradiation was accelerated by the temperature of polymer film during irradiation. The beam heating of materials during ion irradiation was assumed, especially for Ni ion irradiation. The heavy ion irradiation effect of polymers was thought to be much affected by the ion beam heating than the linear energy transfer(LET) of radiation source. (author)

Development of heavy-ion irradiation technique for single-event in semiconductor devices

Energy Technology Data Exchange (ETDEWEB)

Nemoto, Norio; Akutsu, Takao; Matsuda, Sumio [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan). Tsukuba Space Center; Naitoh, Ichiro; Itoh, Hisayoshi; Agematsu, Takashi; Kamiya, Tomihiro; Nashiyama, Isamu

1997-03-01

Heavy-ion irradiation technique has been developed for the evaluation of single-event effects on semiconductor devices. For the uniform irradiation of high energy heavy ions to device samples, we have designed and installed a magnetic beam-scanning system in a JAERI cyclotron beam course. It was found that scanned area was approximately 4 x 2 centimeters and that the deviation of ion fluence from the average value was less than 7%. (author)

Specific heat of 4He and 3He--4He mixtures at their lambda transition

International Nuclear Information System (INIS)

Gasparini, F.M.; Moldover, M.R.

1975-01-01

We have measured the specific heat near the lambda transition of pure 4 He and of five 3 He-- 4 He mixtures up to a mole fraction of 0.39 3 He in 4 He. Our data for 4 He confirm the results of Ahlers revealing an asymmetry in the exponents above and below T/sub lambda/ when the specific heat is represented by a simple-power-law temperature dependence. Our results for these exponents (α = 0.012 plus-or-minus 0.002 and α' = -0.012 plus-or-minus 0.004) differ somewhat from Ahlers's. Our results can be reconciled with the requirement of scaling (α = α') only by supposing substantial contributions to C/sub p/ are made by singular correction terms to a simple power law. The measured specific heat of the mixtures richest in 3 He appears to be finite, continuous, and cusped at the lambda line. These qualitative features have been termed ''renormalization'' by Fisher. An analysis of our mixture data with a power-law temperature dependence does not yield a fully renormalized exponent, but rather an effective exponent. Derivatives at the lambda line were used to calculate the specific heat along paths of constant pressure and constant relative chemical potential.This specific heat behaves very much like C/sub p/ of pure 4 He, this behavior supporting the idea of universality for the specific-heat exponents. It is also true that the same asymmetry in the branches above and below T/sub lambda/ which is []bserved in pure 4 He is retained in the mixtures. The persistence of the asymmetry of C/subp//sub phi/ as one moves along the lambda line towards increasing 3 He concentration (at the saturated vapor pressure of the mixtures) is analogous to the persistence of the asymmetry of C/subp/ as one moves along the lambda line towards increasing pressure in pure 4 He

Heavy ion driven LMF design concept

International Nuclear Information System (INIS)

Lee, E.P.

1991-08-01

The USA Department of Energy has conducted a multi-year study of the requirements, designs and costs for a Laboratory Microfusion Facility (LMF). The primary purpose of the LMF would be testing of weapons physics and effects simulation using the output from microexplosions of inertial fusion pellets. It does not need a high repetition rate, efficient driver system as required by an electrical generating plant. However there would be so many features in common that the design, construction and operation of an LMF would considerably advance the application of inertial confinement fusion to energy production. The DOE study has concentrated particularly on the LMF driver, with design and component development undertaken at several national laboratories. Principally, these are LLNL (Solid State Laser), LANL (Gas Laser), and SNLA (Light Ions). Heavy Ions, although considered a possible LMF driver did not receive attention until the final stages of this study since its program management was through the Office of Energy Research rather than Defense Programs. During preparation of a summary report for the study it was decided that some account of heavy ions was needed for a complete survey of the driver candidates. A conceptual heavy ion LMF driver design was created for the DOE report which is titled LMC Phase II Design Concepts. The heavy ion driver did not receive the level of scrutiny of the other concepts and, unlike the others, no costs analysis by an independent contractor was performed. Since much of heavy ion driver design lore was brought together in this exercise it is worthwhile to make it available as an independent report. This is reproduced here as it appears in the DOE report

Synchrotrons for heavy ions: Bevalac experience

International Nuclear Information System (INIS)

Grunder, H.A.; Gough, R.A.; Alonso, J.R.

1980-10-01

The Bevalac should be viewed not as a model of accelerator hardware - a modern heavy ion complex will look quite different, but as a model for an operating versatile multifaceted, multiuser heavy ion facility. Of value to the planning of a new accelerator such as MARIA is the knowledge of operating modes peculiar to heavy ions and specific hardware requirements to carry out its mission with the mandated flexibility and reliability. This paper starts with a discussion of parameters and machine characteristics most suitable for medical and nuclear science applications. It then covers experience in interleaving these two research programs, and finally, concentrates on accelerator configuratin questions; injectors, repetition rate, vacuum systems and cost criteria which will be relevant to the design of MARIA

Exfoliation of GaAs caused by MeV 1H and 4He ion implantation at left angle 100 right angle , left angle 110 right angle axial and random orientations

International Nuclear Information System (INIS)

Rauhala, E.; Raeisaenen, J.

1994-01-01

The exfoliation procedure of the ion range determination of gaseous implants in single crystal GaAs is investigated. The correlation of the observed crater depth with the ion range is studied for random, left angle 100 right angle and left angle 110 right angle axial orientation high dose implantations of 1.5-2.5 MeV 1 H and 4 He ions. Depending on the experimental conditions, the crater depths corresponded to range values between the modal range and the range maximum. The observed crater depths could be related to the actual He concentration depth distributions by determining the profiles of the 4 He implants by 2.7 MeV proton backscattering. The implantation parameters affecting the exfoliation process, and especially the increase rate of the sample temperature, are investigated. The range distribution parameters for the 1.5 MeV 4 He implants are presented. ((orig.))

7th high energy heavy ion study

International Nuclear Information System (INIS)

Bock, R.; Gutbrod, H.H.; Stock, R.

1985-03-01

These proceedings contain the articles presented at the named conference. They deal with relativistic heavy ion reactions, the expansion and freeze-out of nuclear matter, anomalon experiments, and multifragmentation and particle correlations in heavy ion reactions. See hints under the relevant topics. (HSI)

Highlights of the heavy ion fusion symposium

International Nuclear Information System (INIS)

Keefe, D.

1986-01-01

The current status and prospects for inertial confinement fusion based on the use of intense beams of heavy ions will be described in the light of results presented at the International Symposium on Heavy Ion Fusion, (Washington, DC, May 27-29, 1986)

Highlights of the heavy ion fusion symposium

International Nuclear Information System (INIS)

Keefe, D.

1986-07-01

The current status and prospects for inertial confinement fusion based on the use of intense beams of heavy ions will be described in the light of results presented at the International Symposium on Heavy Ion Fusion, (Washington, DC, May 27-29, 1986)

Ring Current He Ion Control by Bounce Resonant ULF Waves

Science.gov (United States)

Kim, Hyomin; Gerrard, Andrew J.; Lanzerotti, Louis J.; Soto-Chavez, Rualdo; Cohen, Ross J.; Manweiler, Jerry W.

2017-12-01

Ring current energy He ion (˜65 keV to ˜520 keV) differential flux data from the Radiation Belt Storm Probe Ion Composition Experiment (RBSPICE) instrument aboard the Van Allan Probes spacecraft show considerable variability during quiet solar wind and geomagnetic time periods. Such variability is apparent from orbit to orbit (˜9 h) of the spacecraft and is observed to be ˜50-100% of the nominal flux. Using data from the Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) instrument, also aboard the Van Allen Probes spacecraft, we identify that a dominant source of this variability is from ULF waveforms with periods of tens of seconds. These periods correspond to the bounce resonant timescales of the ring current He ions being measured by RBSPICE. A statistical survey using the particle and field data for one full spacecraft precession period (approximately 2 years) shows that the wave and He ion flux variations are generally anticorrelated, suggesting the bounce resonant pitch angle scattering process as a major component in the scattering of He ions.

Local charge exchange of He{sup +} ions at Aluminum surfaces

Energy Technology Data Exchange (ETDEWEB)

Riccardi, P., E-mail: pierfrancesco.riccardi@fis.unical.it [Dipartimento di Fisica, Università della Calabria and INFN – Gruppo collegato di Cosenza, Via P. Bucci cubo 33C, Arcavacata di Rende, Cosenza (Italy); Sindona, A. [Dipartimento di Fisica, Università della Calabria and INFN – Gruppo collegato di Cosenza, Via P. Bucci cubo 33C, Arcavacata di Rende, Cosenza (Italy); Dukes, C.A. [Laboratory for Astrophysics and Surface Physics, Materials Science and Engineering University of Virginia, Charlottesville, VA 22904 (United States)

2017-04-04

We report on experiments designed to observe the correlation between the autoionization of doubly excited helium atoms and the Auger decay of 2p vacancies in Al. The autoionizing states are formed when incident He{sup +*} and He{sup ++} are neutralized by resonant electron capture at the surface. 2p excitation in Al occurs in dielectronic charge transfer during the close encounter of an excited helium ion and an Al atom. These results clarify the mechanism for Al-2p excitation in the case of singly charged ground state He{sup +}(1s) ion impact, where the dielectronic transition occurs after promotion of the 1s electron of incoming ions. - Highlights: • We observe the correlation between autoionization of doubly excited helium atoms and the Auger decay of 2p vacancies in Al. • 2p excitation in Al occurs in dielectronic charge transfer during the close encounter of an excited helium ion and an Al atom. • These results clarify the mechanism for Al-2p excitation in the case of singly charged ground state He{sup +}(1s) ion impact.

A large area position-sensitive ionization chamber for heavy-ion-induced reaction studies

CERN Document Server

Pant, L M; Dinesh, B V; Thomas, R G; Saxena, A; Sawant, Y S; Choudhury, R K

2002-01-01

A large area position-sensitive ionization chamber with a wide dynamic range has been developed to measure the mass, charge and energy of the heavy ions and the fission fragments produced in heavy-ion-induced reactions. The split anode geometry of the detector makes it suitable for both particle identification and energy measurements for heavy ions and fission fragments. The detector has been tested with alpha particles from sup 2 sup 4 sup 1 Am- sup 2 sup 3 sup 9 Pu source, fission fragments from sup 2 sup 5 sup 2 Cf and the heavy-ion beams from the 14UD Mumbai Pelletron accelerator facility. Using this detector, measurements on mass and total kinetic energy distributions in heavy-ion-induced fusion-fission reactions have been carried out for a wide range of excitation energies. Results on deep inelastic collisions and mass-energy correlations on different systems using this detector setup are discussed.

Engineering systems designs for a recirculating heavy ion induction accelerator

International Nuclear Information System (INIS)

Newton, M.A.; Barnard, J.J.; Reginato, L.L.; Yu, S.S.

1991-05-01

Recirculating heavy ion induction accelerators are being investigated as possible drivers for heavy ion fusion. Part of this investigation has included the generation of a conceptual design for a recirculator system. This paper will describe the overall engineering conceptual design of this recirculator, including discussions of the dipole magnet system, the superconducting quadrupole system and the beam acceleration system. Major engineering issues, evaluation of feasibility, and cost tradeoffs of the complete recirculator system will be presented and discussed. 5 refs., 4 figs

Application of alpha spectrometry to the discovery of new elements by heavy-ion-beam bombardment

International Nuclear Information System (INIS)

Nitschke, J.M.

1983-05-01

Starting with polonium in 1898, α-spectrometry has played a decisive role in the discovery of new, heavy elements. For even-even nuclei, α-spectra have proved simple to interpret and exhibit systematic trends that allow extrapolation to unknown isotopes. The early discovery of the natural α-decay series led to the very powerful method of genetically linking the decay of new elements to the well-established α-emission of daughter and granddaughter nuclei. This technique has been used for all recent discoveries of new elements including Z = 109. Up to mendelevium (Z = 101), thin samples suitable for α-spectrometry were prepared by chemical methods. With the advent of heavy-ion accelerators new sample preparation methods emerged. These were based on the large momentum transfer associated with heavy-ion reactions, which produced energetic target recoils that, when ejected from the target, could be thermalized in He gas. Subsequent electrical deposition or a He-jet technique yielded samples that were not only thin enough for α-spectroscopy, but also for α- and #betta#-recoil experiments. Many variations of these methods have been developed and are discussed. For the synthesis of element 106 an aerosol-based recoil transport technique was devised. In the most recent experiments, α-spectrometry has been coupled with the magnetic analysis of the recoils. The time from production to analysis of an isotope has thereby been reduced to 10 - 6 s; while it was 10 - 1 to 10 0 s for He-jets and 10 1 to 10 3 s for rapid chemical separations. Experiments are now in progress to synthesize super heavy elements (SHE) and to analyze them with these latest techniques. Again, α-spectrometry will play a major role since the expected signature for the decay of a SHE is a sequence of α-decays followed by spontaneous fission

Progress in Polarized 3He Ion Source at RCNP

International Nuclear Information System (INIS)

Tanaka, M.; Takahashi, Y.; Shimoda, T.; Yasui, S.; Yosoi, M.; Takahisa, K.; Shimakura, N.; Plis, Yu. A.; Donets, E. D.

2007-01-01

A long history on the polarized 3He ion source developed at RCNP is presented. We started with an 'OPPIS' (Optical Pumping Polarized Ion Source) and later found the fundamental difficulties in the OPPIS. To overcome them an 'EPPIS' (Electron Pumping Polarized Ion Source) was proposed and its validity was experimentally proven. However, a serious technical disadvantage was also found in the EPPIS. To avoid this disadvantage we proposed a new concept, 'SEPIS' (Spin Exchange Polarized Ion Source), which uses an enhanced spin-exchange cross section theoretically expected at low 3He+ incident energies in the 3He+ + Rb system. Next, we describe the present status of the SEPIS development: construction of a bench test device allowing the measurements of not only the spin-exchange cross sections σse but also the electron capture cross sections σec for the 3He+ + Rb system. The latest experimental data on σec are presented and compared with other previous experimental data and the theoretical calculations.Finally, a design study of the SEPIS for practical use in nuclear (cyclotron) and particle physics (synchrotron) is shortly mentioned

Development of heavy ion linear accelerators

International Nuclear Information System (INIS)

Bomko, V.A.; Khizhnyak, N.A.

1981-01-01

A review of the known heavy ion accelerators is given. It is stated that cyclic and linear accelerators are the most perspective ones in the energy range up to 10 MeV/nucleon according to universality in respect with the possibility of ion acceleration of the wide mass range. However, according to the accelerated beam intensity of the heavier ions the linear accelerators have considerable advantages over any other types of accelerators. The review of the known heavy ion linac structures permits to make the conclusion that a new modification of an accelerating structure of opposite pins excited on a H-wave is the most perspective one [ru

Heavy ion storage rings

International Nuclear Information System (INIS)

Schuch, R.

1987-01-01

A brief overview of synchrotron storage rings for heavy ions, which are presently under construction in different accelerator laboratories is given. Ions ranging from protons up to uranium ions at MeV/nucleon energies will be injected into these rings using multiturn injection from the accelerators available or being built in these laboratories. After injection, it is planned to cool the phase space distribution of the ions by merging them with cold electron beams or laser beams, or by using stochastic cooling. Some atomic physics experiments planned for these rings are presented. 35 refs

High energy heavy ions: techniques and applications

International Nuclear Information System (INIS)

Alonso, J.R.

1985-04-01

Pioneering work at the Bevalac has given significant insight into the field of relativistic heavy ions, both in the development of techniques for acceleration and delivery of these beams as well as in many novel areas of applications. This paper will outline our experiences at the Bevalac; ion sources, low velocity acceleration, matching to the synchrotron booster, and beam delivery. Applications discussed will include the observation of new effects in central nuclear collisions, production of beams of exotic short-lived (down to 1 μsec) isotopes through peripheral nuclear collisions, atomic physics with hydrogen-like uranium ions, effects of heavy ''cosmic rays'' on satellite equipment, and an ongoing cancer radiotherapy program with heavy ions. 39 refs., 6 figs., 1 tab

High energy density in matter produced by heavy ion beams

International Nuclear Information System (INIS)

1989-07-01

This Annual Report summarizes research activities carried out in 1988 in the framework of the government-funded program 'High Energy Density in Matter produced by Heavy Ion Beams'. It addresses fundamental problems of the generation of heavy ion beams and the investigation of hot dense plasmas produced by these beams. Its initial motivation and its long-term goal is the feasibility of inertial confinement fusion by intense heavy ion beams. Two outstanding events deserve to be mentioned explicity, the Heavy Ion Inertial Fusion Conference held in Darmstadt and organized by GSI end of June and the first heavy ion beam injected into the new SIS facility in November. The former event attracted more than hundred scientists for three days to the 4th Conference in this field. This symposium showed the impressive progress since the last conference in Washington two years ago. In particular the first beams in MBE-4 at LBL and results of beam plasma interaction experiments at GSI open new directions for future investigations. The ideas for non-Lionvillean injection into storage rings presented by Carlo Rubbia will bring the discussion of driver scenarios into a new stage. The latter event is a milestone for both machine and target experiments. It characterizes the beginning of the commissioning phase for the new SIS/ESR facility which will be ready for experiments at the end of this year. The commissioning of SIS is on schedule and first experiments can start at the beginning of 1990. A status report of the accelerator project is included. Theoretical activities were continued as in previous years, many of them providing guide lines for future experiments, in particular for the radiation transport aspects and for beam-plasma interaction. (orig.)

Report of the heavy-ion fusion task group

International Nuclear Information System (INIS)

Sawyer, G.A.; Booth, L.A.; Henderson, D.B.; Jameson, R.A.; Kindel, J.M.; Knapp, E.A.; Pollock, R.; Talbert, W.L.; Thode, L.E.; Williams, J.M.

1980-02-01

An assessment of heavy-ion fusion has been completed. Energetic heavy ions, for example 10-GeV uranium, provided by an rf linac or an induction linac, are used as alternatives to laser light to drive inertial confinement fusion pellets. The assessment has covered accelerator technology, transport of heavy-ion beams, target interaction physics, civilian power issues, and military applications. It is concluded that particle accelerators promise to be efficient pellet drivers, but that there are formidable technical problems to be solved. It is recommended that a moderate level research program on heavy-ion fusion be pursued and that LASL should continue to work on critical issues in accelerator development, beam transport, reactor systems studies, and target physics over the next few years

Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

International Nuclear Information System (INIS)

Grosso, M.F. del; Chappa, V.C.; Arbeitman, C.R.; Garcia Bermudez, G.; Behar, M.

2009-01-01

In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

Swift heavy ion irradiation effects on carbonyl and trans-vinylene groups in high and low density polyethylene

Energy Technology Data Exchange (ETDEWEB)

Grosso, M.F. del, E-mail: delgrosso@tandar.cnea.gov.a [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Chappa, V.C. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Arbeitman, C.R. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); Garcia Bermudez, G. [Gerencia de Investigacion y Aplicaciones, TANDAR-CNEA (Argentina); CONICET (Argentina); Escuela de Ciencia y Tecnologia, UNSAM (Argentina); Behar, M. [Instituto de Fisica, UFRGS, Porto Alegre (Brazil)

2009-10-01

In this work, we have studied the effects of swift heavy ion irradiation on the creation of new functional groups in high and low density polyethylene (HDPE and LDPE). Polymers were irradiated with different ions (6.77 MeV He and 47 MeV Li) and fluences. The induced changes were analyzed by Fourier transform infrared (FTIR) spectroscopy. Creation and damage cross sections for some groups were compared for two different types of PE.

Nanoindentation on V–4Ti alloy irradiated by H and He ions

International Nuclear Information System (INIS)

Yang, Yitao; Zhang, Chonghong; Meng, Yancheng; Liu, Juan; Gou, Jie; Xian, Yongqiang; Song, Yin

2015-01-01

V–4Ti and V samples were irradiated by H/He ions with various energies to produce a damage plateau in the region from surface to the depth of 1.5 um at room temperature. Nanoindentation was performed to investigate the hardening behavior of the two materials under irradiation. It is found that the relation of maximum depth of plastic zone and indentation depth is not a fixed value. The maximum depth of plastic zone decreases with increase of damage level. Nix and Gao model was used to fit the measured hardness to obtain a hardness value H 0 excluding indentation size effect (ISE), which can be used to characterize the hardening effect induced by irradiation. After fitting the data of H 0 , it is found that there is an exponential relation between the H 0 and damage level for both the V–4Ti and V materials. When the damage level is higher than ∼0.2 dpa, the hardness increases slowly, this indicates a slow increase of pinning centers in samples at this damage level. Comparing the hardening fraction of V–4Ti and V samples, significant hardening can be seen for V sample, and it becomes severe especially at damage higher than ∼0.2 dpa. The irradiation hardening resistance property of V–4Ti alloy is better than that of pure V

Accelerators for heavy ion fusion

International Nuclear Information System (INIS)

Bangerter, R.O.

1985-10-01

Large fusion devices will almost certainly produce net energy. However, a successful commercial fusion energy system must also satisfy important engineering and economic constraints. Inertial confinement fusion power plants driven by multi-stage, heavy-ion accelerators appear capable of meeting these constraints. The reasons behind this promising outlook for heavy-ion fusion are given in this report. This report is based on the transcript of a talk presented at the Symposium on Lasers and Particle Beams for Fusion and Strategic Defense at the University of Rochester on April 17-19, 1985

Electron-electron correlation in two-photon double ionization of He-like ions

Science.gov (United States)

Hu, S. X.

2018-01-01

Electron correlation plays a crucial role in quantum many-body physics ranging from molecular bonding and strong-field-induced multielectron ionization, to superconducting in materials. Understanding the dynamic electron correlation in the photoionization of relatively simple quantum three-body systems, such as He and He-like ions, is an important step toward manipulating complex systems through photoinduced processes. Here we have performed ab initio investigations of two-photon double ionization (TPDI) of He and He-like ions (L i+,B e2 + , and C4 +) exposed to intense attosecond x-ray pulses. Results from such fully correlated quantum calculations show weaker and weaker electron correlation effects in TPDI spectra as the ionic charge increases, which is opposite to the intuition that the absolute increase of correlation in the ground state should lead to more equal energy sharing in photoionization. These findings indicate that the final-state electron-electron correlation ultimately determines the energy sharing of the two ionized electrons in TPDI.

Investigations in atomic physics by heavy ion projectiles

International Nuclear Information System (INIS)

Berenyi, D.

1983-01-01

The utilization of heavy ion reactions in atomic physics is surveyed. The basic collision mechanisms and their consequences in atomic physics are summarized. The atomic and electronic processes during and after heavy ion collisions are reviewed as functions of the projectile energy. The main detection and measuring methods are described. Reviews of new information about the structure of electronic cloud and about fundamental processes based on the analysis of heavy ion reaction data are given. (D.Gy.)

International school-seminar on heavy ion physics

International Nuclear Information System (INIS)

Oganesyan, Yu.Ts.

1990-01-01

The reports of the International school-seminar on heavy ion physics are presented. Scientific program of the school-seminar covers a wide spectrum of the today trends of investigations conducted using heavy ion beams within the energy range from several MeV/nucleon up to several GeV/nucleon

Searching for Jets in Heavy Ion Collisions

International Nuclear Information System (INIS)

Salur, Sevil

2008-01-01

Jet quenching measurements using leading particles and their correlations suffer from known biases, which can be removed via direct reconstruction of jets in central heavy ion collisions. In this talk, we discuss several modern jet reconstruction algorithms and background subtraction techniques that are appropriate to heavy ion collisions

Comparison of secondary ion emission yields for poly-tyrosine between cluster and heavy ion impacts

International Nuclear Information System (INIS)

Hirata, K.; Saitoh, Y.; Chiba, A.; Yamada, K.; Takahashi, Y.; Narumi, K.

2010-01-01

Emission yields of secondary ions necessary for the identification of poly-tyrosine were compared for incident ion impacts of energetic cluster ions (0.8 MeV C 8 + , 2.4 MeV C 8 + , and 4.0 MeV C 8 + ) and swift heavy monoatomic molybdenum ions (4.0 MeV Mo + and 14 MeV Mo 4+ ) with similar mass to that of the cluster by time-of-flight secondary ion mass analysis combined with secondary ion electric current measurements. The comparison revealed that (1) secondary ion emission yields per C 8 + impact increase with increasing incident energy within the energy range examined, (2) the 4.0 MeV C 8 + impact provides higher emission yields than the impact of the monoatomic Mo ion with the same incident energy (4.0 MeV Mo + ), and (3) the 2.4 MeV C 8 + impact exhibits comparable emission yields to that for the Mo ion impact with higher incident energy (14 MeV Mo 4+ ). Energetic cluster ion impacts effectively produce the characteristic secondary ions for poly-tyrosine, which is advantageous for highly sensitive amino acid detection in proteins using time-of-flight secondary ion mass analysis.

HEAVY ION LINEAR ACCELERATOR

Science.gov (United States)

Van Atta, C.M.; Beringer, R.; Smith, L.

1959-01-01

A linear accelerator of heavy ions is described. The basic contributions of the invention consist of a method and apparatus for obtaining high energy particles of an element with an increased charge-to-mass ratio. The method comprises the steps of ionizing the atoms of an element, accelerating the resultant ions to an energy substantially equal to one Mev per nucleon, stripping orbital electrons from the accelerated ions by passing the ions through a curtain of elemental vapor disposed transversely of the path of the ions to provide a second charge-to-mass ratio, and finally accelerating the resultant stripped ions to a final energy of at least ten Mev per nucleon.

Recent advances of microbial breeding via heavy-ion mutagenesis at IMP.

Science.gov (United States)

Hu, W; Li, W; Chen, J

2017-10-01

Nowadays, the value of heavy-ion mutagenesis has been accepted as a novel powerful mutagen technique to generate new microbial mutants due to its high linear energy transfer and high relative biological effectiveness. This paper briefly reviews recent progress in developing a more efficient mutagenesis technique for microbial breeding using heavy-ion mutagenesis, and also presents the outline of the beam line for microbial breeding in Heavy Ion Research Facility of Lanzhou. Then, new insights into microbial biotechnology via heavy-ion mutagenesis are also further explored. We hope that our concerns will give deep insight into microbial breeding biotechnology via heavy-ion mutagenesis. We also believe that heavy-ion mutagenesis breeding will greatly contribute to the progress of a comprehensive study industrial strain engineering for bioindustry in the future. There is currently a great interest in developing rapid and diverse microbial mutation tool for strain modification. Heavy-ion mutagenesis has been proved as a powerful technology for microbial breeding due to its broad spectrum of mutation phenotypes with high efficiency. In order to deeply understand heavy-ion mutagenesis technology, this paper briefly reviews recent progress in microbial breeding using heavy-ion mutagenesis at IMP, and also presents the outline of the beam line for microbial breeding in Heavy Ion Research Facility of Lanzhou (HIRFL) as well as new insights into microbial biotechnology via heavy-ion mutagenesis. Thus, this work can provide the guidelines to promote the development of novel microbial biotechnology cross-linking heavy-ion mutagenesis breeding that could make breeding process more efficiently in the future. © 2017 The Society for Applied Microbiology.

Combined He3 cryostats and He3-He4 dilution refrigerators

International Nuclear Information System (INIS)

Kovac, L.; Balla, J.

1974-07-01

A modular set of equipment was designed, which consists of a 4 He Dewar vessel with a very low evaporation rate, having a pumped 4 He bath in which either a 3 He cryostat or a dilution refrigerator within removable inserts can be placed. Any of them can be simply and rapidly connected to the versatile Dewar, auxiliary 4 He-, vacuum; and 3 He- 4 He systems. Two such sets have already been completed and can be used at temperatures from 1.5K to 0.05K for thermodynamic and neutron diffraction measurements. The performance of all inserts was stable and reliable, differences between the cryostats and runs were small - nearly all within the accuracy of temperature determination. The construction of a lot of parts is identical, allowing rapid manufacture. Assembling and repairs are simple, all parts are easily accessible. (K.A.)

Heavy Ion Fusion Accelerator Research (HIFAR) year-end report, April 1, 1989--September 30, 1989

International Nuclear Information System (INIS)

1989-12-01

This report contains the following topics on heavy ion fusion: MBE-4 drifting beam quadrupole operating range; transverse emittance growth in MBE-4; an improved ion source for MBE-4; drifting beam studies on MBE-4; 2-MV injector; improvements in lifetime of the C + source; injector control system; Maxwell spark gap test update; ILSE cosine 2θ quadrupole magnet development; electrostatic quadrupole prototype development activity; induction accelerator cell development; effect of a spread in beamlet currents on longitudinal stability; and heavy ion linac driver analysis

Equilibrium charge state distributions of high energy heavy ions

International Nuclear Information System (INIS)

Clark, R.B.; Grant, I.S.; King, R.; Eastham, D.A.; Joy, T.

1976-01-01

Equilibrium charge state fractions have been measured for N, O, Ne, S, Ar and Kr ions at 1.04 MeV/nucleon after passing through various stripping materials. Further data were obtained at higher energy for S ions (4.12 MeV/nucleon) and Ar ions (4.12 and 9.6 MeV/nucleon). The mean charge fractions can be fitted to universal curves for both solid and gaseous strippers. Measurements of the equilibrium fraction of krypton ions at 1.04 MeV/nucleon passing through heavy vapours have shown that a higher average charge state is obtained than for lighter gaseous strippers. (Auth.)

MBE-4: an induction linac experiment for heavy ion fusion

International Nuclear Information System (INIS)

Fessenden, T.J.; Avery, R.T.; Brodzik, D.A.

1986-06-01

The multiple-beam induction linac approach to a heavy ion fusion driver features continuous current amplification along the accelerator and a minimum of transverse beam manipulation from source to pellet. Current amplification and bunch length control require careful shaping of the accelerating voltages. This driver approach exploits developments in electron induction linac technology that have occurred within the last 15 years at LBL, LLNL and NBS. MBE-4 is a four beam induction linac that models much of the accelerator physics of the electrostatically focused section of a considerably longer induction accelerator. Four parallel Cs + beams are electrostatically focussed and will be accelerated from 200 keV to approximately one MeV when the experiment is complete in the spring of 1987. The current in each of the four beams will increase from 10 to 40 mA due to both increase in beam speed and shortening of the bunch length. Results of experiments with the injector and first eight accelerating gaps are presented

Heavy ion medical accelerator in chiba

International Nuclear Information System (INIS)

Hirao, Y.; Ogawa, H.; Yamada, S.

1992-12-01

The HIMAC (Heavy Ion Medical Accelerator in Chiba) construction project has been promoted by NIRS (National Institute of Radiological Sciences) as one of the projects of 'Comprehensive 10 year Strategy for Cancer Control' HIMAC is the first heavy-ion accelerator dedicated to medicine in the world, and its design parameters are based on the radiological requirements. It consists of two types of ion sources, an RFQ and an Alvarez linacs, dual synchrotron rings, high energy beam transport lines, and irradiation facilities for treatment and experiments. This report mainly describes the outline of the structure and performance of each HIMAC subsystem. (J.P.N.)

Heavy ion induction linacs for fusion

International Nuclear Information System (INIS)

Bangerter, R.O.; Ho, D.D.M.

1991-01-01

In 1976 Denis Keefe proposed the heavy ion induction linac as a driver for inertial confinement fusion (ICF) power plants. Subsequent research has established that heavy ion fusion (HIF) is potentially an attractive energy source and has identified the issues that must be resolved to make HIF a reality. The principal accelerator issues are achieving adequately low transverse and longitudinal emittance and acceptable cost. Results from the single and multiple beam experiments at LBL on transverse emittance are encouraging. A predicted high current longitudinal instability that can affect longitudinal emittance is currently being studied. This paper presents an overview of economics and ICF target requirements and their relationship to accelerator design. It also presents a summary of the status of heavy ion induction linac research. It concludes with a discussion of research plans, including plans for the proposed Induction Linac Systems Experiments (ILSE)

Dynamical limitations to heavy-ion fusion

International Nuclear Information System (INIS)

Back, B.B.

1983-01-01

In spite of the many attempts to synthesize superheavy elements in recent years, these efforts have not yet been successful. Recent improved theoretical models of heavy-ion fusion reactions suggest that the formation of super-heavy elements is hindered by the dynamics of the process. Several recent experiments lend support to these theories. The necessity of an excess radial velocity (extra push) over the Coulomb barrier in order to induce fusion is observed experimentally as predicted by the theory. So is a new reaction mechanism, called quasi-fission which tend to exhaust the part of the reaction cross section, which would otherwise lead to fusion. The present study shows that the angular distribution of fragments from quasi-fission processes are very sensitive to the occurrence of this reaction mechanism. A slight modification of one parameter in the theory demanded by the observation of quasi-fission for lighter projectiles via the angular distributions, has the consequence of posing even more-stringent limitations on heavy-ion-fusion reactions. This reduces even further the possibility for synthesizing and identifying superheavy elements in heavy-ion-fusion reactions

Giant resonance phenomena in the electron impact ionization of heavy atoms and ions

International Nuclear Information System (INIS)

Younger, S.M.

1986-01-01

Heavy atoms and ions offer an interesting opportunity to study atomic physics in a region where the atomic structure is dominated by the interelectronic interactions. One illustration of this is the profound term dependence of atomic orbitals for certain configurations of heavy atoms and ions. The appearance of giant scattering resonances in the cross sections for ionization of heavy atoms by electron impact is a manifestation of resonance behavior. Such resonant structures arise from the double well nature of the scattering potential and have recently been identified in the cross sections for the electron impact ionization of several xenon-like ions. The results of calculations showing effects for a variety of other ions are summarized. 7 refs., 4 figs

Transport of heavy ions in inertial confinement fusion

International Nuclear Information System (INIS)

Parvazian, A.; Shahbandari Gouchani, A.

2007-01-01

In this article we have investigated the interaction of heavy ions (U) with a target (Au). In inertial confinement fusion method Interaction between heavy ion beam and target was simulated, Numerical analysis of the Boltzmann Fokker Planck equation used in order to optimize the material of the target and Energy deposition of ion beam to electrons and ions of target and The thickness of the target were calculated.

Quantum electrodynamical effects in heavy highly-charged ions

International Nuclear Information System (INIS)

Yerokhin, V.A.; Artemyev, A.N.; Indelicato, P.; Shabaev, V.M.

2003-01-01

The present status of theoretical calculations of QED effects in highly charged ions is reviewed for several important cases: the Lamb shift in heavy H-like ions, the 2p 1/2 -2s transition energy in heavy Li-like ions, and the bound-electron g factor in H-like ions. Theoretical predictions are compared with experimental results. Special attention is paid to the discussion of uncertainties of theoretical predictions

Coupled channels effects in heavy ion elastic scattering

International Nuclear Information System (INIS)

Bond, P.D.

1977-01-01

The effects of inelastic excitation on the elastic scattering of heavy ions are considered within a coupled channels framework. Both Coulomb and nuclear excitation results are applied to 18 O + 184 W and other heavy ion reactions

Large-space cluster model calculations for the 3He(3He,2p)4He and 3H(3H,2n)4He reactions

International Nuclear Information System (INIS)

Csoto, Attila; Langanke, Karlheinz

1999-01-01

The 3 He( 3 He, 2p) 4 He and 3 H( 3 H, 2n) 4 He reactions are studied in a microscopic cluster model. We search for resonances in the 3 He+ 3 He and 4 He + p + p channels using methods that treat the two- and three-body resonance asymptotics correctly. Our results show that the existence of a low-energy resonance or virtual state, which could influence the 7 Be and 8 B solar neutrino fluxes, is rather unlikely. Our calculated 3 He( 3 He, 2p) 4 He and 3 H( 3 H, 2n) 4 He cross sections are in a good general agreement with the experimental data

Inertial fusion with heavy ion beams

International Nuclear Information System (INIS)

Bock, R.; Hofmann, I.; Arnold, R.

1984-01-01

The underlying principle of inertial confinement is the irradiation of a small pellet filled with DT-fuel by laser or particle beams in order to compress the fuel and ignite it. As 'drivers' for this process large laser installations and light-ion devices have been built since then and the results obtained during the past few years have increased our confidence, that the ignition conditions might be reached. Further conditions, however, have to be fulfilled for operating a power plant. In particular, the driver needs to have enough efficiency to be economical, and for a continuous energy production a high repetition rate and availability is required. It is less than ten years since it was realized that heavy ion beams might be a promising candidate for achieving inertial confinement fusion (ICF). Due to the evolution of high-energy and heavy-ion physics during the past 25 years, accelerators have attained a high technical and technological standard and an excellent operational reliability. Nevertheless, the heavy ion driver for a fusion power plant requires beam specifications exceeding those of existing accelerators considerably. (Auth.)

Specific gene mutations induced by heavy ions

International Nuclear Information System (INIS)

Freeling, M.; Karoly, C.W.; Cheng, D.S.K.

1980-01-01

This report summarizes our heavy-ion research rationale, progress, and plans for the near future. The major project involves selecting a group of maize Adh1 mutants induced by heavy ions and correlating their altered behavior with altered DNA nucleotide sequences and sequence arrangements. This research requires merging the techniques of classical genetics and recombinant DNA technology. Our secondary projects involve (1) the use of the Adh gene in the fruit fly, Drosophila melanogaster, as a second system with which to quantify the sort of specific gene mutants induced by heavy ions as compared to x rays, and (2) the development of a maize Adh1 pollen in situ monitor for environmental mutagens

Calculation of the substitutional fraction of ion-implanted He in an Fe target

OpenAIRE

Erhart, Paul; Marian, Jaime

2010-01-01

Ion-implantation is a useful technique to study irradiation damage in nuclear materials. To study He effects in nuclear fusion conditions, He is co-implanted with damage ions to reproduce the correct He/dpa ratios in the desired or available depth range. However, the short-term fate of these He ions, i.e over the time scales of their own collisional phase, has not been yet unequivocally established. Here we present an atomistic study of the short-term evolution of He implantation in an Fe sub...

Accelerator development for heavy ion fusion

International Nuclear Information System (INIS)

Talbert, W.L. Jr.; Sawyer, G.A.

1980-01-01

Accelerator technology development is presented for heavy ion drivers used in inertial confinement fusion. The program includes construction of low-velocity ''test bed'' accelerator facilities, development of analytical and experimental techniques to characterize ion beam behavior, and the study of ion beam energy deposition

Hypernuclei, dibaryon and antinuclei production in high energy heavy ion collisions: Thermal production vs. coalescence

International Nuclear Information System (INIS)

Steinheimer, J.; Gudima, K.; Botvina, A.; Mishustin, I.; Bleicher, M.; Stöcker, H.

2012-01-01

We study the production of (hyper-)nuclei and dibaryons in most central heavy ion collisions at energies of E lab =1-160 A GeV. In particular we are interested in clusters produced from the hot and dense fireball. The formation rate of strange and non-strange clusters is estimated by assuming thermal production from the intermediate phase of the UrQMD-hydro hybrid model and alternatively by the coalescence mechanism from a hadronic cascade model. Both model types are compared in detail. For most energies we find that both approaches agree in their predictions for the yields of the clusters. Only for very low beam energies, and for dibaryons including Ξ's, we observe considerable differences. We also study the production of anti-matter clusters up to top RHIC energies and show that the observation of anti- 4 He and even anti- 4 Λ He is feasible. We have found a considerable qualitative difference in the energy dependence of the strangeness population factor R H when comparing the thermal production with the coalescence results.

Direct photons in heavy-ion collisions

Energy Technology Data Exchange (ETDEWEB)

Baeuchle, Bjoern

2010-12-13

Direct photon emission from heavy-ion collisions has been calculated and compared to available experimental data. Three different models have been combined to extract direct photons from different environments in a heavy-ion collision: Thermal photons from partonic and hadronic matter have been extracted from relativistic, non-viscous 3+1-dimensional hydrodynamic calculations. Thermal and non-thermal photons from hadronic interactions have been calculated from relativistic transport theory. The impact of different physics assumptions about the thermalized matter has been studied. The models used for the determination of photons from both hydrodynamic and transport calculations have been elucidated and their numerical properties tested. The origin of direct photons, itemised by emission stage, emission time, channel and baryon number density, has been investigated for various systems, as have the transverse momentum spectra and elliptic flow patterns of direct photons. Taking into account the full (vacuum) spectral function of the rho-meson decreases the direct photon emission by approximately 10% at low photon transverse momentum. In all systems that have been considered -- heavy-ion collisions at E{sub lab}=35 AGeV and 158 AGeV, (s{sub NN}){sup 1/2}=62.4 GeV, 130 GeV and 200 GeV -- thermal emission from a system with partonic degrees of freedom is greatly enhanced over that from hadronic systems, while the difference between the direct photon yields from a viscous and a non-viscous hadronic system (transport vs. hydrodynamics) is found to be very small. Predictions for direct photon emission in central U+U-collisions at 35 AGeV have been made. (orig.)

Direct photons in heavy-ion collisions

International Nuclear Information System (INIS)

Baeuchle, Bjoern

2010-01-01

Direct photon emission from heavy-ion collisions has been calculated and compared to available experimental data. Three different models have been combined to extract direct photons from different environments in a heavy-ion collision: Thermal photons from partonic and hadronic matter have been extracted from relativistic, non-viscous 3+1-dimensional hydrodynamic calculations. Thermal and non-thermal photons from hadronic interactions have been calculated from relativistic transport theory. The impact of different physics assumptions about the thermalized matter has been studied. The models used for the determination of photons from both hydrodynamic and transport calculations have been elucidated and their numerical properties tested. The origin of direct photons, itemised by emission stage, emission time, channel and baryon number density, has been investigated for various systems, as have the transverse momentum spectra and elliptic flow patterns of direct photons. Taking into account the full (vacuum) spectral function of the rho-meson decreases the direct photon emission by approximately 10% at low photon transverse momentum. In all systems that have been considered -- heavy-ion collisions at E lab =35 AGeV and 158 AGeV, (s NN ) 1/2 =62.4 GeV, 130 GeV and 200 GeV -- thermal emission from a system with partonic degrees of freedom is greatly enhanced over that from hadronic systems, while the difference between the direct photon yields from a viscous and a non-viscous hadronic system (transport vs. hydrodynamics) is found to be very small. Predictions for direct photon emission in central U+U-collisions at 35 AGeV have been made. (orig.)

Heavy Flavor Physics in Heavy-Ion Collisions with STAR Heavy Flavor Tracker

International Nuclear Information System (INIS)

Yifei Zhang

2010-01-01

Heavy quarks are a unique tool to probe the strongly interacting matter created in relativistic heavy-ion collisions at RHIC energies. Due to their large mass, energetic heavy quarks are predicted to lose less energy than light quarks by gluon radiation when they traverse a Quark-Gluon Plasma. In contrast, recent measurements of non-photonic electrons from heavy quark decays at high transverse momentum (p T ) show a jet quenching level similar to that of the light hadrons. Heavy quark are produced mainly at early stage in heavy-ion collisions, thus they are proposed to probe the QCD medium and to be sensitive to bulk medium properties. Ultimately, their flow behavior may help establish whether light quarks thermalize. But due to the absence of the measurement of B-mesons and precise measurement of D-mesons, it is difficult to separate bottom and charm contributions experimentally in current non-photonic electron measurements for both spectra and elliptic flow v 2 . Therefore, topological reconstruction of D-mesons and identification of electrons from charm and bottom decays are crucial to understand the heavy flavor production and their in medium properties. The Heavy Flavor Tracker (HFT) is a micro-vertex detector utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precise measurement of charmed and bottom hadrons. We present a study on the open charm nuclear modification factor, elliptic flow v 2 and λ c measurement as well as the measurement of bottom mesons via a semi-leptonic decay. (author)

Jets in relativistic heavy ion collisions

International Nuclear Information System (INIS)

Wang, Xin-Nian; Gyulassy, M.

1990-09-01

Several aspects of hard and semihard QCD jets in relativistic heavy ion collisions are discussed, including multiproduction of minijets and the interaction of a jet with dense nuclear matter. The reduction of jet quenching effect in deconfined phase of nuclear matter is speculated to provide a signature of the formation of quark gluon plasma. HIJING Monte Carlo program which can simulate events of jets production and quenching in heavy ion collisions is briefly described. 35 refs., 13 figs

Comparison of string models for heavy ion collisions

International Nuclear Information System (INIS)

Werner, K.

1990-01-01

An important method to explore new domains in physics is to compare new results with extrapolations from known areas. For heavy ion collision this can be done with string models, which extrapolate from light to heavy systems and which also may be used to extrapolate to higher energies. That does not mean that these string models are only background models, one may easily implement new ideas on top of the known aspects, providing much more reliable models than those formed from scratch. All the models to be considered in this paper have in common that they consist of three independent building blocks: (a) geometry, (b) string formation and (c) string fragmentation. The geometry aspect is treated quite similar in all models: nucleons are distributed inside each nucleus according to some standard parameterization of nuclear densities. The nuclei move through each other on a straight line trajectory, with all the nucleon positions being fixed. Whenever a projectile and a target nucleon come close, they interact. Such an interaction results in string formation. In the last step these strings decay into observable hadrons according to some string fragmentation procedure. The three building blocks are independent, so one can combine different methods in an arbitrary manner. Therefore rather than treating the models one after the other, the author discusses the procedures for string formation and string fragmentation as used by the models. He considers string models in a very general sense, so he includes models where the authors never use the word string, but which may be most naturally interpreted as string models and show strong similarities with real string models. Although very important he does not discuss - for time and space reasons - recent developments concerning secondary scattering

Pion correlations in heavy ion collision

International Nuclear Information System (INIS)

Venema, L.

1991-01-01

Charged π-correlations are a well established experimental technique to obtain information about π-source sizes. This is, however, not the case for π 0 's, as they decay into photons, resulting in measurements of 4 photon correlations. Here is described what these correlations are, what the problems are to detect and interpret them. These correlations are an additional way to get more information out of the heavy ion collisions. (orig.)

Heavy-ion driver design and scaling

International Nuclear Information System (INIS)

Bieri, R.; Monsler, M.; Meier, W.; Stewart, L.

1992-01-01

Parametric models for scaling heavy-ion driver designs are described. Scaling of target performance and driver cost is done for driver parameters including driver energy, number of beams, type of superconductor used in focusing magnets, maximum magnetic field allowed at the superconducting windings, linear quadrupole array packing fraction mass, and ion charge state. The cumulative accelerator voltage and beam currents are determined from the Maschke limits on beam current for each choice of driver energy and post-acceleration pulse duration. The heavy-ion driver is optimized over the large available driver parameter space. Parametric studies and the choice of a base driver model are described in a companion paper

Study of inter sub-shell and inter shell electron correlations in 4d open-shell heavy atomic ions

International Nuclear Information System (INIS)

Koike, Fumihiro

2009-01-01

The effect of correlations between 4p, 4d, and 4f has been studied extensively. The characteristic spectral structures of 4p - 4d and 4d - 4f optical transitions, due to the unique structures of N = 4 open sub-shells in heavy atomic ions, have been studied theoretically. To gain an insight of this effect, a series of careful MCDF calculations for 4d q (q = 0 to 10) atomic ions with atomic numbers Z = 48 to 56 has been carried out. The difference of orbital energy differences between 4p and 4d orbitals and 4d and 4f orbitals coincidently falls within the range of a few % for almost all the atomic ions investigated. The 4p 6 4d4f and 4p 5 4d 3 configurations may mix strongly, and the optical 4p - 4d and 4d - 4f transitions may take place coherently, providing us with quite a peculiar EUV emission spectrum. The effect of spectral narrowing and shift is expected to be quite common to the atomic specieds with the atomic numbers in the range Z = 48 to 56.

Suppression and Two-Particle Correlations of Heavy Mesons in Heavy-Ion Collisions

Energy Technology Data Exchange (ETDEWEB)

Cao, Shanshan [Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Qin, Guang-You [Institute of Particle Physics and Key Laboratory of Quark and Lepton Physics (MOE), Central China Normal University, Wuhan, 430079 (China); Bass, Steffen A. [Department of Physics, Duke University, Durham, NC 27708 (United States)

2016-12-15

We study the medium modification of heavy quarks produced in heavy-ion collisions. The evolution of heavy quarks inside the QGP is described using a modified Langevin framework that simultaneously incorporates their collisional and radiative energy loss. Within this framework, we provide good descriptions of the heavy meson suppression and predictions for the two-particle correlation functions of heavy meson pairs.

Radiation defects in lithium fluoride induced by heavy ions

Energy Technology Data Exchange (ETDEWEB)

Trautmann, C.; Schwartz, K.; Steckenreiter, T. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Costantini, J.M. [CEA Centre d`Etudes de Bruyeres-le-Chatel, 91 (France). DPTA/SPMC; Toulemonde, M. [Centre Interdisciplinaire de Recherches avec les Ions Lourds (CIRIL), 14 - Caen (France)

1998-07-01

Single crystals of lithium fluoride were irradiated with various species of heavy ions in the energy regime between 1 and 30 MeV/u. The induced radiation damage was studied with techniques such as optical absorption spectroscopy, small-angle x-ray scattering, chemical etching and profilometry, complemented by annealing experiments. Clear evidence is given for a complex track structure and defect morphology. Single defects such as F-centers are produced in a large halo of several tens of nanometers around the ion trajectory. The defect creation in this zone is similar to that under conventional radiation. For heavy ions above a critical energy loss of 10 keV/nm, new effects occur within a very small core region of 2-4 nm in diameter. The damage in this zone is responsible for chemical etching and for a characteristic anisotropic x-ray scattering. It is assumed that in this core, complex defect aggregates (e.g., cluster of color centers, molecular anions and vacancies) are created. Their formation is only slightly influenced by the irradiation temperature and takes place even at 15 K where diffusion processes of primary defects are frozen. Furthermore, irradiation with heavy ions leads to pronounced swelling effects which can be related to an intermediate zone of around 10 nm around the ion path. (orig.) 40 refs.

Experiments with stored heavy ions

International Nuclear Information System (INIS)

Fick, D.; Habs, D.; Jaeschke, E.

1985-02-01

The success of newly-developed methods of phase space cooling in proton and antiproton storage rings was sufficient for an examination of whether these methods could also be applied in storage rings for heavy ions. An expansion of these methods to heavy ion beams seems attractive for all sorts of reasons. Recently, this area was extensively discussed in a series of working meetings with the result that heavy ion storage rings are to be built for use in atomic and nuclear physics, with integrated radiation cooling and stochastic cooling, but primarily electron cooling. The current state of research and planning for the storage experiment is described. It is not intended to be a structural specification worked out in detail. The general design of the ring, however, has been established, and experimental details have deliberately been kept flexible, to thereby allow very different sorts of experiments to be conducted. The ring described with a maximum magnetic rigidity of Bp = 1.5 Tm, is designed in quadripartite symmetry. The total circumference is approximately 35 m, and there are four straight sections each 3.5 m long for the electron cooling sections, the experimental equipment, as well as HF system and injection. One of the most desirable properties of the reservoir is the multi-charge mode, which will significantly improve the operation which heavy ion beams, which reverse charge in electron cooling sections, target and residual vacuum. Initial considerations are presented with regard to stochastic and electron cooling. A review of possible classes of experiments is given and the schedule and financing of the project is outlined. 46 refs

Progress and tendency in heavy ion irradiation mutation breeding

International Nuclear Information System (INIS)

Zhou Libin; Li Wenjian; Qu Ying; Li Ping

2008-01-01

In recent years, the intermediate energy heavy ion biology has been concerned rarely comparing to that of the low-energy ions. In this paper, we summarized the advantage of a new mutation breeding method mediated by intermediate energy heavy ion irradiations. Meanwhile, the present state of this mutation technique in applications of the breeding in grain crops, cash crops and model plants were introduced. And the preview of the heavy ion irradiations in gene-transfer, molecular marker assisted selection and spaceflight mutation breeding operations were also presented. (authors)

Dosimetry and radiobiology of negative pions and heavy ions

International Nuclear Information System (INIS)

Raju, M.R.

1978-01-01

The depth dose distribution of pion beams has not been found superior to protons. Pion radiation quality at the plateau region is comparable to conventional low-LET radiations, and radiobiology results also indicate RBE values close to unity. In the pion stopping region, the radiation quality increases considerably. Radiobiology data for negative pions at the Bragg peak position clearly indicate the increase in RBE and the reduction in OER. Even at the Bragg peak position, compared to fast neutrons, the average LET of negative pions is lower. Pion radiobiology data have indicated lower RBE values and higher OER values compared to fast neutrons. The radiation quality of fast neutrons is in between that of carbon and neon ions at the peak region and that of neon ions at the plateau is lower than for fast neutrons. The mean LET value for helium ions, even at the distal end of the peak, is lower than for fast neutrons. Dose localization of heavy ions has been found to decrease slowly with increasing charge of the heavy ion. The intercellular contact that protects cells after exposure to low-LET radiations is not detected after exposure to heavy ions. Single and fractionated doses of heavy ions produce dose-response curves for heavy ions having reduced shoulders but similar slopes when compared to gamma rays. Fractionated treatments of heavy ions produce an enhanced effect in the peak region compared to the plateau region and could lead to a substantial gain in therapeutic ratio. The OER for protons was similar to that for x rays. The OER values for negative pions, helium ions, and carbon ions were larger, for neon ions similar, and for argon ions smaller when compared to fast neutrons.Negative pions, helium ions, and carbon ions may be very effective clinically because the radiation quality of these beams is similar to that of the mixed scheme of neutrons and x rays

Review of BNL heavy ion physics

International Nuclear Information System (INIS)

Miake, Yasuo.

1990-01-01

With an intent to search for a new state of matter, a relativistic heavy ion program was started in 1986 at BNL. Several interesting features have been reported from BNL-AGS heavy ion experiments, among which are: the enhanced K + /π + ratio and the larger left-angle m t right-angle for K + and proton. Comparisons between ∼pp, pA and SiA collisions are discussed for m t and dn/dy distributions. 33 refs., 9 figs., 1 tab

Localization effects in heavy ion collisions

International Nuclear Information System (INIS)

Donangelo, R.J.

1984-01-01

Radial and angular localization in heavy ion reactions on deformed nuclei is discussed. A theoretical method appropriate to study these localization effects is briefly described and then applied to the determination of deformed heavy ion potentials from inclastic scattering data. It is argued that one-and two-nucleon transfer reactions on deformed nuclei can provide a probe of nuclear structure in high angular momentum states and be at least qualitatively analyzed in the light of these localization concepts. (Author) [pt

Ultra-relativistic heavy ions and cosmic rays

International Nuclear Information System (INIS)

McLerran, L.

1983-05-01

The collisions of ultra-relativistic heavy ions, E/sub /N/ greater than or equal to 1 TeV/nucleon are most interesting, since, at these energies, matter is produced at sufficiently high energy density that a quark-gluon plasma has a good chance to form. Very heavy ions are also most interesting since the matter forms in a larger volume than for light ions, and the matter is at a somewhat higher energy density. At very high energies with very heavy ions there is great flexibility in the experimental signals which might be studied, as well as the nature of the matter which is produced. The fragmentation region and central region provide different environments where a plasma might form. The former is baryon rich while the central region is high temperature with low baryon number density and is not accessible except at very high energies

Superfluidity of a dilute 3He-4He solution

International Nuclear Information System (INIS)

Soda, Toshio

1993-01-01

The interaction between two 3 He atoms is calculated by taking into account the backflow effect of 3 He by the 4 He in the 3 He- 4 He mixture. The effect contributes solely to the P wave part of the interaction. The repulsive S wave part of the contact interaction contributes to the exchange interaction between the 3 He atoms, while the direct one phonon exchange interaction contributes both to the S and P wave attractive interactions. The overall contribution to the attractive interaction is dominated by the P wave part and the superfluidity in the P wave is more predominant than in the S wave for the 5 % dilute 3 He- 4 He solution, and vice versa for the 1.3 % solution. (author)

Study on broad beam heavy ion CT

International Nuclear Information System (INIS)

Ohno, Yumiko; Kohno, Toshiyuki; Sasaki, Hitomi; Nanbu, S.; Kanai, Tatsuaki

2003-01-01

To achieve the heavy ion radiotherapy more precisely, it is important to know the distribution of the electron density in a human body, which is highly related to the range of charged particles. From a heavy ion CT image, we can directly obtain the 2-D distribution of the electron density in a sample. For this purpose, we have developed a broad beam heavy ion CT system. The electron density was obtained using some kinds of solutions targets. Also the dependence of the spatial resolution on the target size and the kinds of beams was estimated in this work using cylinders targets of 40, 60 and 80 mm in diameter, each of them has a hole of 10 mm in diameter at the center of it. (author)

Surface structure of Cr0.5 Ti0.5N coatings after heavy ions irradiation and annealing

International Nuclear Information System (INIS)

Kislitsin, Sergey; Gorlachev, Igor; Uglov, Vladimir

2015-01-01

Results of surface structure investigations of TiCrN coating on carbon steel after irradiation by helium, krypton and xenon heavy ions are reported in the present publication. The series of Cr50Ti50N coatings on carbon steel with thickness of 50,..., 300 nm were formed by vacuum arc deposition techniques. Specimens with TiCrN coating on carbon steel were irradiated by low energy 4 He +1 (22 keV) and 4 He +2 (40 keV) ions and high energy Xe +18 and Kr +14 ions with energy of 1.5 MeV/nucleon. Fluence of He ions was 1.0x10 17 ion.cm -2 , fluence of Xe and Kr ions was 5x10 14 -1.0x10 15 ion.cm -2 , irradiation temperature did not exceed 150 deg. C. Study of surface structure was performed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Methods of Roentgen diffractometry and Rutherford backscattering was applied for determination of structure and thickness of coating. In case of irradiation with Xe +18 and Kr +14 ions an investigation of surface morphology and structure was done after successive two hours vacuum annealing of irradiated samples at temperatures 400 deg. C, 500 deg. C and 600 deg. C. It was shown that after irradiation by Xe and Kr ions on the surface of coating convexities appear, surface density of which correlates with ion flux. In the case of Xe, ions irradiation generated convexities of spherical and elongated shape with dimensions ranging from ten to hundreds nm. In the case of Kr ions, only spherical globules were generated, dimensions of which are 10-30 nm. The most likely explanation of observed surface damage is that: convexities on the surface are generated at ion bombardment of specimens with coating. Convexities are the traces of ions passing through coating and they are due to structural reconstruction at energy release along a trajectory of ions braking. Convexities of elongated shape represent overlapping traces from two passing ions. When the projective range of Xe and Kr ions exceeds coating thickness, damage

L X-ray emission induced by heavy ions

Energy Technology Data Exchange (ETDEWEB)

Pajek, M. [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Banaś, D., E-mail: d.banas@ujk.edu.pl [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Braziewicz, J.; Majewska, U.; Semaniak, J. [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Fijał-Kirejczyk, I. [The Institute of Atomic Energy, 05-400 Otwock-Świerk (Poland); Jaskóła, M.; Czarnacki, W.; Korman, A. [The National Centre for Nuclear Research, 05-400 Otwock-Świerk (Poland); Kretschmer, W. [Physikalisches Institut, Universität Erlangen-Nürnberg, D-91058 Erlangen (Germany); Mukoyama, T. [Institute for Nuclear Research, Hungarian Academy of Sciences (ATOMKI), H-4026 Debrecen (Hungary); Trautmann, D. [Institut für Physik, Universität Basel, Basel (Switzerland)

2015-11-15

Particle-induced X-ray emission (PIXE) technique is usually applied using typically 1 MeV to 3 MeV protons or helium ions, for which the ion-atom interaction is dominated by the single ionization process. For heavier ions the multiple ionization plays an increasingly important role and this process can influence substantially both the X-ray spectra and atomic decay rates. Additionally, the subshell coupling effects are important for the L- and M-shells ionized by heavy ions. Here we discuss the main features of the X-ray emission induced by heavy ions which are important for PIXE applications, namely, the effects of X-ray line shifts and broadening, vacancy rearrangement and change of the fluorescence and Coster–Kronig yields in multiple ionized atoms. These effects are illustrated here by the results of the measurements of L X-ray emission from heavy atoms bombarded by 6 MeV to 36 MeV Si ions, which were reported earlier. The strong L-subshell coupling effects are observed, in particular L{sub 2}-subshell, which can be accounted for within the coupling subshell model (CSM) developed within the semiclassical approximation. Finally, the prospects to use heavy ions in PIXE analysis are discussed.

Relativistic heavy ion facilities: worldwide

International Nuclear Information System (INIS)

Schroeder, L.S.

1986-05-01

A review of relativistic heavy ion facilities which exist, are in a construction phase, or are on the drawing boards as proposals is presented. These facilities span the energy range from fixed target machines in the 1 to 2 GeV/nucleon regime, up to heavy ion colliders of 100 GeV/nucleon on 100 GeV/nucleon. In addition to specifying the general features of such machines, an outline of the central physics themes to be carried out at these facilities is given, along with a sampling of the detectors which will be used to extract the physics. 22 refs., 17 figs., 3 tabs

Central collisions of heavy ions

International Nuclear Information System (INIS)

Fung, Sun-yiu.

1991-10-01

This report describes the activities of the Heavy Ion Physics Group at the University of California, Riverside from October 1, 1990 to September 30, 1991. During this period, our program focuses on particle production at AGS energies, and correlation studies at the Bevalac in nucleus central collisions. We participated in the preparation of letters of intent for two RHIC experiments -- the OASIS proposal and the Di-Muon proposal -- and worked on two RHIC R ampersand D efforts -- a silicon strip detector project and a muon-identifier project. A small fraction of time was also devoted to physics programs outside the realm of heavy ion reactions by several individuals

Heavy flavours in ultra-relativistic heavy ions collisions; Les saveurs lourdes dans les collisions d'ions lourds ultra-relativistes

Energy Technology Data Exchange (ETDEWEB)

Rosnet, Ph

2008-01-15

The ultra-relativistic collisions of heavy ions are the today's only means to tackle in laboratory conditions the phase diagram in quantum chromodynamics and the strong interaction. The most recent theoretical studies predict a phase transition between the cold nuclear matter (a hadronic gas) and a plasma of quarks and gluons. Heavy flavour can characterize the nuclear matter produced in a heavy ion collision as well as its spatial-temporal evolution. Their study can be made through their decay into muons. The first part of this work presents the issue of ultra-relativistic heavy ion collisions and the role of heavy flavours. In the second part the author reviews the results of experiments performed at RHIC and particularly presents the analysis of the mass spectrum of dimuons in the Phenix experiment. The third part describes the muon trigger system of the Alice experiment at CERN and the expected performances for the study of di-muons.

Recent advances in high current vacuum arc ion sources for heavy ion fusion

CERN Document Server

Qi Nian Sheng; Prasad, R R; Krishnan, M S; Anders, A; Kwan, J; Brown, I

2001-01-01

For a heavy ion fusion induction linac driver, a source of heavy ions with charge states 1+-3+, approx 0.5 A current beams, approx 20 mu s pulse widths and approx 10 Hz repetition rates is required. Thermionic sources have been the workhorse for the Heavy Ion Fusion (HIF) program to date, but suffer from heating problems for large areas and contamination. They are limited to low (contact) ionization potential elements and offer relatively low ion fluxes with a charge state limited to 1+. Gas injection sources suffer from partial ionization and deleterious neutral gas effects. The above shortcomings of the thermionic ion sources can be overcome by a vacuum arc ion source. The vacuum arc ion source is a good candidate for HIF applications. It is capable of providing ions of various elements and different charge states in short and long pulse bursts and high beam current density. Under a Phase-I STTR from DOE, the feasibility of the vacuum arc ion source for the HIF applications was investigated. We have modifie...

Studying extremely peripheral collisions of relativistic heavy ions

International Nuclear Information System (INIS)

Fatyga, M.

1990-01-01

Relativistic heavy ion facilities have been proposed (and in some cases constructed) with an intent to search for a new state of matter, a quark gluon plasma. As with all tools in the experimental physics, one should always search for ways in which relativistic heavy ions can be used to study physical phenomena beyond this original goal. New possibilities for a study of higher order photonuclear excitations in extremely peripheral collisions of relativistic heavy ions are discussed in this contribution. Data on the electromagnetic and nuclear fragmentation of a 14.6Gev/nucleon 28 Si projectile are presented

Low frequency RFQ linacs for heavy ion fusion

International Nuclear Information System (INIS)

Moretti, A.; Watson, J.M.; Martin, R.L.; Lari, R.J.; Stockley, R.L.

1982-01-01

Low frequency, radio frequency quadrupole (RFQ) structures are under study at Argonne National Laboratory (ANL) as the low-velocity portion of an rf linac driver for heavy ion inertial confinement fusion. Besides offering a direct comparison with the present ANL front end, it would provide a second low-velocity Xe +1 linac for funneling experiments at 22.9 MeV. Heavy ion RFQ accelerators are characterized by their low rf operating frequency of about 10 MHz. The large size of a manifold-fed four-vane, 10 MHz RFQ resonator structure (about 6 m in diameter) makes it unacceptable for heavy ions; therefore, alternate structures are under study at Argonne. The structures under study are: (1) a Wideroe-type structure with external stub lines, (2) a Wideroe-type structure with the stub lines internal to the structure, (3) a split coaxial line resonator with modulated vanes, and (4) a interdigital line resonator with modulated cylindrical rods. The split coaxial line resonator seems best at this low frequency. It is compact and very efficient. About 15.5 m of linac structure excited with 560 kW of rf power is sufficient to accelerate 30 mA of Xe +1 with 97% transmission efficiency from 250 keV to 3 MeV

Coulomb excitation of /sup 182/ /sup 184/ /sup 186/W and /sup 166/Er with /sup 4/He and /sup 16/O ions

Energy Technology Data Exchange (ETDEWEB)

McGowan, F K; Milner, W T; Sayer, R O; Robinson, R L; Stelson, P H [Oak Ridge National Lab., Tenn. (USA)

1977-10-10

The Coulomb excitation reaction induced by /sup 4/He ions selectively excites 2/sup +/ and 3/sup -/ states by direct E2 and E3 Coulomb excitation. In this paper, new results are presented from ..gamma..-ray spectroscopy with 15 MeV /sup 4/He ions on a natural abundance target of W. In particular, a 3/sup -/ state in each isotope, /sup 182/ /sup 184/ /sup 186/W, was observed by direct E3 excitation. In addition to obtaining B(Elambda, 0 ..-->.. J = lambda for excitation of each state, information on the reduced transition probabilities for the different decay modes of these states is given. The Coulomb excitation probabilities of the 2'/sup +/ states at 786 keV in /sup 166/Er and at 737 keV in /sup 186/W were measured with /sup 16/O and /sup 4/He ions by the backscattered particle-gamma coincidence method in order to determine the static electric quadrupole moment Qsub(2'). For /sup 166/Er, Qsub(2')=2.11+-0.37 e.b which is in agreement with (Qsub(2'))sub(rot) and for /sup 186/W, Qsub(2')=1.17+-0.30 e.b which is in agreement with Kumar-Baranger model calculations and is significantly smaller than (Qsub(2'))sub(rot). This deviation of the measured Qsub(2') from (Qsub(2'))sub(rot) implies in the framework of the Kumar-Baranger calculations a strong coupling between ..beta..- and ..gamma..-vibrational bands. On the other hand, the observed upper limit for B(E2, 2'' ..-->.. 2') does not confirm this implication.

Exotic phenomena in collisions of heavy ions

International Nuclear Information System (INIS)

Soff, G.; Schramm, S.; Reus, T. de; Mehler, G.; Reinhardt, J.; Mueller, B.; Greiner, W.; Mueller, U.

1985-08-01

To exemplify current theoretical investigations we discuss three different topics. After a presentation of the underlying theoretical framework for ionization processes we will sketch the possibility to employ delta-electron emission as a clock to measure nuclear reaction times in intermediate energy collisions of very heavy ions. Besides the phenomenon of vacuum decay into a new twofold negatively charged stable vacuum ground state, electron excitation in heavy ion collisions may be employed for the determination of delay and deceleration times on the nuclear time scale, i.e. offering an atomic clock, operating in the range 10 -21 -10 -24 s. In deep-inelastic heavy ion collisions this provides a test for classical nuclear reaction models. In collisions at intermediate energies an independent measurement of the deceleration time is of interest for comparison, e.g., with the results of the pion bremsstrahlung model. After that we investigate the influence of one or more pockets in the ion scattering potential on the energy distribution of emitted positrons within a quantum mechanical framework. Finally we very briefly consider some phenomenological corrections to the Dirac equation and its consequences on electron binding energies in heavy and superheavy atoms. (orig./HSI)

Complementary scattered and recoiled ion data from TOF-E heavy ion elastic recoil detection analysis

International Nuclear Information System (INIS)

Johnston, P.N.; El Bouanani, M.; Stannard, W.B.; Bubb, I.F.; Cohen, D.D.; Dytlewski, N.; Siegele, R.

1998-01-01

The advantage of Time of Flight and Energy (ToF-E) Heavy Ion Elastic Recoil Detection Analysis (HIERDA) over Rutherford Backscattering (RBS) analysis is its mass and energy dispersive capabilities. The mass resolution of ToF-E HIERDA deteriorates for very heavy elements. The limitation is related to the poor energy resolution of Si detectors for heavy ions. While the energy spectra from ToF-E HIERDA data are normally used to extract depth profiles, this work discusses the benefits of using the time spectra of both the recoiled and the scattered ions for depth profiling. The simulation of the complementary scattered and recoiled ion time spectra improves depth profiling and reduced current limitations when dealing with very heavy ions, such as Pt, Bi, Ta. (authors)

Energy straggling of heavy ions in solids

International Nuclear Information System (INIS)

Cowern, N.E.B.

1979-08-01

The energy-loss straggling of heavy ions has been studied, principally in the Born Approximation region v > zv 0 . Measurements were made with 5.486 MeV α particles, 5 - 48 MeV 16 0 ions, and 3 - 36 MeV 12 C ions, incident on thin uniform Al foils. The thickness uniformity of the foils was studied with a proton microbeam and a surface profiler, and their homogeneity, purity and isotropy were investigated by electron microscope, proton backscattering, and X-ray diffraction studies. Using the Bethe theory of energy loss the charge-exchange model of energy straggling for heavy ions is confirmed. (author)

Heavy ion induced damage in MgAl sub 2 O sub 4 , an inert matrix candidate for the transmutation of minor actinides

CERN Document Server

Wiss, T

1999-01-01

Magnesium aluminum spinel (MgAl sub 2 O sub 4) is a material selected as a possible matrix for transmutation of minor actinides by neutron capture or fission in nuclear reactors. To study the radiation stability of this inert matrix, especially against fission product impact, irradiations with heavy energetic ions or clusters have been performed. The high electronic energy losses of the heavy ions in this material led to the formation of visible tracks as evidenced by transmission electron microscopy for 30 MeV C sub 6 sub 0 -Buckminster fullerenes and for ions of energy close to or higher than fission energy ( sup 2 sup 0 sup 9 Bi with 120 MeV and 2.38 GeV energy). The irradiations at high energies showed a pronounced degradation of the spinel. Additionally, MgAl sub 2 O sub 4 exhibited a large swelling for irradiation at high fluences with fission products of fission energy (here I-ions of 72 MeV) and at temperatures <= 500 deg. C. These observations are discussed from the technological point of view in ...

Summary talk at the symposium on relativistic heavy ion research G.S.I., Darmstadt, Germany

International Nuclear Information System (INIS)

Grunder, H.A.

1978-03-01

Ideas expressed at the symposium and the general state of relativistic heavy-ion research are reviewed. The relationship with biology and medicine and with fusion is addressed. What has been learned about heavy ions and suggested possible next research steps are tabulated. 3 figures, 4 tables

Applications of heavy-ion reactions on hydrogen isotopes

International Nuclear Information System (INIS)

Evers, E.J.

1987-01-01

This thesis describes various aspects of 'inverse' reactions between the lightest nuclides, hydrogen and deuterium, and heavy ions in the range from carbon to phosphorus. The reactions studied in this thesis always result in one light ejectile and one excited heavy nucleus. Coincidence experiments have been performed in which both the emitted light particle and the gamma radiation emitted by the excited heavy nucleus produced, are detected. Ch. 1 describes the system built for the acquisition of data obtained in such coincidence experiments. Ch. 2 describes precision measurements of nuclear lifetimes and stopping powers. Coincident Doppler shift attenuation (DSA) experiments were performed with the reaction 2 H( 31 P,pγ) 32 P at E( 31 P 7+ )=50 MeV and thin Ti 2 H targets on Au, Ag and Cu backings. Mean lifetimes of the E x =513, 1150, 1323 and 1755 levels were determined with experimental stopping powers of Forster et al. These lifetimes were used as input in further analysis of the experimental data and of an additional experiment with a target on Mg backing to determine a consistent set of stopping power data for P ions with a velocity in the range 0-8(c/137) in the four materials mentioned. Ch.'s 3 and 4 deal with narrow resonances in reactions of nitrogen and fluorine beams with hydrogen targets. In Ch. 3 a method is described for the calibration of analyzing-magnet systems of heavy-ions accelerators. Ch. 4 describes an experiment to investigate the hydrogen concentration in silicon nitride films using a resonant inverse nuclear reaction. This method turns out to be a very suitable one for determining hydrogen concentration profiles with a good depth resolution over a large depth. 69 refs.; 23 figs.; 7 tabs

Effects of heavy ion temperature on low-frequency kinetic Alfven waves

International Nuclear Information System (INIS)

Yang, L.; Wu, D. J.

2011-01-01

Heavy ion-electron (or proton) temperature ratio varies in a wide range in the solar and space environment. In this paper, proton and heavy ion temperatures are included in a three-fluid plasma model. For the specified parameters, low-frequency (<< heavy ion gyrofrequency) kinetic Alfven waves (KAWs) with sub- and super-Alfvenic speeds are found to coexist in the same plasma environment. Our results show that the temperature ratio of heavy ions to electrons can considerably affect the dispersion, propagation, and electromagnetic polarizations of the KAWs. In particular, the temperature ratio can increase the ratio of parallel to perpendicular electric fields and the normalized electric to magnetic field ratio, the variations of which are greatly different in regions with a high heavy ion temperature and with a low one. The results may help to understand the physical mechanism of some energization processes of heavy ions in the solar and space plasma environment. Effects of the ratio of electron thermal to Alfven speeds and the heavy ion abundance on these parameters are also discussed.

Kinetic energy dissipation in heavy-ion collisions

International Nuclear Information System (INIS)

Fedotov, S.I.; Jolos, R.V.; Kartavenko, V.G.

1979-01-01

Kinetic energy dissipation mechanism is considered in deep inelastic heavy-ion collisions. It is shown that the significant part of the kinetic energy loss can be explained by the excitation of the nuclear matter multipole vibrations. The main contribution of the energy dissipation is given by the time dependent heavy-ion interaction potential renormalized due to the nuclear excitations, rather than by the velocity proportional frictional forces

Elastic and radiative heavy quark interactions in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Uphoff, Jan; Fochler, Oliver; Xu, Zhe; Greiner, Carsten

2015-01-01

Elastic and radiative heavy quark interactions with light partons are studied with the partonic transport model named the Boltzmann approach to multiparton scatterings (BAMPSs). After calculating the cross section of radiative processes for finite masses in the improved Gunion–Bertsch approximation and verifying this calculation by comparing to the exact result, we study elastic and radiative heavy quark energy loss in a static medium of quarks and gluons. Furthermore, the full 3 + 1D space–time evolution of gluons, light quarks, and heavy quarks in ultra-relativistic heavy-ion collisions at the BNL Relativistic Heavy-Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) are calculated with BAMPS including elastic and radiative heavy flavor interactions. Treating light and heavy particles on the same footing in the same framework, we find that the experimentally measured nuclear modification factor of charged hadrons and D mesons at the LHC can be simultaneously described. In addition, we calculate the heavy flavor evolution with an improved screening procedure from hard-thermal-loop calculations and confront the results with experimental data of the nuclear modification factor and the elliptic flow of heavy flavor particles at the RHIC and the LHC. (paper)

Continuous preparation of Fe3O4 nanoparticles through Impinging Stream-Rotating Packed Bed reactor and their electrochemistry detection toward heavy metal ions

International Nuclear Information System (INIS)

Fan, Hong-Lei; Zhou, Shao-Feng; Gao, Jing; Liu, You-Zhi

2016-01-01

We reported the continuous preparation and electrochemical behavior toward heavy metal ions of the Fe 3 O 4 nanoparticles (Fe 3 O 4 NPs). This Fe 3 O 4 NPs were fabricated through a novel Impinging Stream-Rotating Packed Bed reactor with a high production rate of 2.23 kg/hour. The as-prepared Fe 3 O 4 NPs were quasi-spherical with a mean diameter of about 10 nm and shown the characteristics of superparamagnetism with the saturated magnetization of 60.5 emu/g. The electrochemical characterization of the as-prepared Fe 3 O 4 NPs toward heavy metal ions were evaluated using square wave anodic stripping voltammetry (SWASV) analysis. The results indicated that the modified electrode could be used to individual detection of Pb(II), Cu(II), Hg(II) and Cd(II). In particular, the modified electrode exhibited the selective detection toward Pb(II) with higher sensitivity of 14.9 μA/μM, while the response to Cu(II), Hg(II) and Cd(II) were negligible. Besides, the modified electrode shown good stability and potential practical applicability in the electrochemical determination of Pb(II). This above results offered a simple method for continuous preparation sensing materials in the application field of electrochemical detection of toxic metal ions through the technology of process intensification. - Highlights: • Fe 3 O 4 nanoparticles were continuous prepared through IS-RPB reactor. • The Fe 3 O 4 nanoparticles showed selective detection of heavy metal ions. • It exhibited favorable sensitivity (14.9 μA μM −1 ) and LOD (0.119 μM) for Pb(II). • The as-prepared nanoparticles showed favorable potential application.

New beam for the CERN fixed target heavy ion programme

CERN Document Server

Hill, C E; O'Neill, M

2002-01-01

The physicists of the CERN heavy ion community (SPS fixed target physics) have requested lighter ions than the traditional lead ions, to scale their results and to check their theories. Studies have been carried out to investigate the behaviour of the ECR4 for the production of an indium beam. Stability problems and the low melting point of indium required some modifications to the oven power control system which will also benefit normal lead ion production. Present results of the source behaviour and the ion beam characteristics will be presented.

Compact time-zero detector for heavy ions

International Nuclear Information System (INIS)

Weissenberger, E.; Kast, W.; Goennenwein, F.

1979-01-01

A time-zero detector for flight-time measurements with heavy ions is described. The ions traverse a thin foil and the secondary electrons splashed from the foil are detected in a channel plate multiplier. A timing signal is derived from the multiplier pulse. The novel features of the detector are its simplicity and compactness of design. The time resolution achieved for the full energy and mass span of fission fragments from the spontaneous fission of 252 Cf used as a heavy ion source is 115 ps (fwhm). (Auth.)

Development of a Time Projection Chamber using CF4 gas for relativistic heavy ion experiments

International Nuclear Information System (INIS)

Isobe, T.; Hamagaki, H.; Ozawa, K.; Inuzuka, M.; Sakaguchi, T.; Matsumoto, T.; Kametani, S.; Kajihara, F.; Gunji, T.; Kurihara, N.; Oda, S.X.; Yamaguchi, Y.L.

2006-01-01

A prototype Time Projection Chamber (TPC) using pure CF 4 gas was developed for possible use in heavy ion experiments. Basic characteristics such as gain, drift velocity, longitudinal diffusion and attenuation length of produced electrons were measured with the TPC. At an electric field of 900V/cm, the drift velocity and longitudinal diffusion for 1cm drift were obtained as 10cm/μs and 60μm, respectively. The relatively large gain fluctuation is explained to be due to the electron attachment process in CF 4 . These characteristics are encouraging for the measurement of the charged particle trajectories under high multiplicity conditions at RHIC

Ultra-relativistic heavy ions and the CBA

International Nuclear Information System (INIS)

McLerran, L.D.

1982-01-01

The study of ultra-relativistic heavy ions at an accelerator such as the CBA provides a unique glimpse of matter as it may have appeared in the early universe. This hot dense matter very probably appears as a quark-gluon plasma which expands and cools into hadronic matter. The CBA would provide data at the very highest energies, and produce matter at the highest energy densities. The possibility of using a cyclotron to inject very heavy ions into the AGS and then into the CBA would also allow the production of quark-gluon matter at higher energy densities than would light ions, and would make the matter in a larger volume where surface effects are minimized. At the highest energies with very heavy ions, there is great flexibility in the experimental signals which might be studied, as well as the nature of the matter which is produced. Some of the possibilities are discussed

Imaging instrument for positron emitting heavy ion beam injection

International Nuclear Information System (INIS)

Llacer, J.; Chatterjee, A.; Jackson, H.C.; Lin, J.C.; Zunzunegui, M.V.

1978-10-01

The design and performance of an instrument for the imaging of coincidence annihilation gamma rays emitted from the end point of the trajectories of radioactive high-energy heavy ions is described. The positron-emitting heavy ions are the result of nuclear fragmentation of accelerated heavy ions used in cancer therapy or diagnostic medicine. The instrument constructed is capable of locating the ion beam trajectory end point within 1 mm for an injected activity of 200 nanoCi in a measurement time of 1 sec in some favorable conditions. Limited imaging in three dimensions is also demonstrated

Heavy-ion microscopy

International Nuclear Information System (INIS)

Kraft, G.; Yang, T.C.H.; Richards, T.; Tobias, C.A.

1980-01-01

This chapter briefly describes the techniques of optical microscopy, scanning and transmission electron microscopy, soft x-ray microscopy and compares these latter techniques with heavy-ion microscopy. The resolution obtained with these various types of microscopy are compared and the influence of the etching procedure on total resolution is discussed. Several micrographs of mammalian cells are included

Microdosimetry spectra and RBE of 1H, 4He, 7Li and 12C nuclei in water studied with Geant4

International Nuclear Information System (INIS)

Burigo, Lucas; Pshenichnov, Igor; Mishustin, Igor; Bleicher, Marcus

2014-01-01

A Geant4-based Monte Carlo model for Heavy-Ion Therapy (MCHIT) is used to study radiation fields of 1 H, 4 He, 7 Li and 12 C beams with similar ranges (∼160–180 mm) in water. Microdosimetry spectra are simulated for wall-less and walled Tissue Equivalent Proportional Counters (TEPCs) placed outside or inside a phantom, as in experiments performed, respectively, at NIRS, Japan and GSI, Germany. The impact of fragmentation reactions on microdosimetry spectra is investigated for 4 He, 7 Li and 12 C, and contributions from nuclear fragments of different charge are evaluated for various TEPC positions in the phantom. The microdosimetry spectra measured on the beam axis are well described by MCHIT, in particular, in the vicinity of the Bragg peak. However, the simulated spectra for the walled TEPC far from the beam axis are underestimated. Relative Biological Effectiveness (RBE) of the considered beams is estimated using a modified microdosimetric-kinetic model. Calculations show a similar rise of the RBE up to 2.2–2.9 close to the Bragg peak for helium, lithium and carbon beams compared to the modest values of 1–1.2 at the plateau region. Our results suggest that helium and lithium beams are also promising options for cancer therapy

Specific-heat measurements on dilute 3He-4He mixtures

International Nuclear Information System (INIS)

Zeeuw, H.C.M. van der.

1985-01-01

The author measured the specific heat of dilute 3 He- 4 He mixtures in the concentration range from X = 1 x 10 -3 to X = 3 x 10 -3 and in the temperature range from 100 mK to 600 mK. This has been done by means of a thermal relaxation method. This method provides some interesting features and is applied, to our knowledge, for the first time to dilute 3 He- 4 He mixtures. To reach the required temperature range for our experiments a 4 He circulating 3 He- 4 He dilution refrigerator has been constructed. The results confirm the deviation of the 3 He contribution to the specific heat from the ideal Fermi gas behaviour. (Auth.)

Preliminary study on mutagenic effects of heavy ions irradiation on maize inbred lines

International Nuclear Information System (INIS)

Yu Lixia; Li Wenjian; Xie Hongmei; Chen Xuejun; Chen Jing

2010-01-01

In order to study mutagenic effects of different heavy ions irradiation on maize inbred lines,corn seeds of Zheng58, Lu9801, Jinxiang4C-1, CSR24001, 308 and 478 were irradiated with 12 C 6+ and 36 Ar 18+ ions. The experimental results showed that the germination rate and planting percent were different after irradiation. The wettish seeds had higher sensibility to heavy ion irradiation. The leaf type of the plant appeared visible changes in M 1 generation. In M 2 generation, great changes had taken place in economic traits, many of which are beneficial mutation. Some beneficia1 mutation could be stably inherited in M 3 generation. From the above, it can be predicted that heavy ions irradiation is an effective means of genetic improvement of maize. (authors)

Prospects for high energy heavy ion accelerators

International Nuclear Information System (INIS)

Leemann, C.

1979-03-01

The acceleration of heavy ions to relativistic energies (T greater than or equal to 1 GeV/amu) at the beam intensities required for fundamental research falls clearly in the domain of synchrotons. Up to date, such beams have been obtained from machines originally designed as proton acccelerators by means of modified RF-programs, improved vacuum and, most importantly, altered or entirely new injector systems. Similarly, for the future, substantial changes in synchrotron design itself are not foreseen, but rather the judicious application and development of presently known principles and technologies and a choice of parameters optimized with respect to the peculiarities of heavy ions. The low charge to mass ratio, q/A, of very heavy ions demands that superconducting magnets be considered in the interest of the highest energies for a given machine size. Injector brightness will continue to be of highest importance, and although space charge effects such as tune shifts will be increased by a factor q 2 /A compared with protons, advances in linac current and brightness, rather than substantially higher energies are required to best utilize a given synchrotron acceptance. However, high yeilds of fully stripped, very heavy ions demand energies of a few hundred MeV/amu, thus indicating the need for a booster synchrotron, although for entirely different reasons than in proton facilities. Finally, should we consider colliding beams, the high charge of heavy ions will impose severe current limitations and put high demands on system design with regard to such quantities as e.g., wall impedances or the ion induced gas desorption rate, and advanced concepts such as low β insertions with suppressed dispersion and very small crossing angles will be essential to the achievement of useful luminosities

Present status and perspectives of heavy ion studies on cells and organisms

International Nuclear Information System (INIS)

Yang, T.C.; Craise, L.M.; Mei Mantong.

1992-01-01

Biomedical research of heavy ion radiation has been an unique and highly active field in past two decades. Through these intensive research efforts, significant amount of quantitative and qualitative data, which provide insights into biological effects, have been obtained. RBE and LET relationship has been well established for cell inactivation, somatic mutation, and cancer induction. In addition, the effects of oxygen and cell cycle on radiosensitivity of mammalian cells, exposed to heavy ions, have been examined. In spite of such large quantitative information, there is only very limited understanding of the mechanisms of these effects of heavy ions. It remains to be discovered how heavy ions cause various biological effects and why heavy ions can be so effective in producing these effects. As the understanding of molecular effects of heavy ion increases, the potential use of heavy ions in probing molecular mechanism(s) of mutation and neoplastic cell transformation becomes more evident. The exciting progress of heavy ion research in past decades only leads to more challenging questions. Answers for these interesting questions can be obtained by developing new heavy ion facilities for single particle irradiation, by further studies with modern molecular biology techniques, and by innovative approaches. Knowledge from biomedical heavy ion research will not only enhance our basic understanding of fundamental biological processes, such as repair, cell growth control, differentiation, etc., but also help in assessing health risk of space radiation and in improving animal and plant breeding. Research in heavy ion radiobiology is gradually growing from infant to mature stage. (author)

Heavy Ion Current Transients in SiGe HBTs

Science.gov (United States)

Pellish, Jonathan A.; Reed, Robert A.; Vizkelethy, Gyorgy; McMorrow, Dale; Ferlet-Cavrois, Veronique; Baggio, Jacques; Paillet, Philipe; Duhanel, Olivier; Phillips, Stanley D.; Sutton, Akil K.;

The mobilies of chiral molecular cluster ions in He gas

International Nuclear Information System (INIS)

Saito, Kazuyuki; Matoba, Shiro; Koizumi, Tetsuo; Kojima, Takao M; Tanuma, Hajime; Shiromaru, Haruo

2012-01-01

We measured the mobilities of Li + -(2-butanol) and Li + -(limonene) ions in He gas at room temperature using a drift tube mass spectrometer. The zero field mobilities of Li + -(2-Butanol) and Li + -(Limonene) were much lower than the polarization limit, indicating that the geometric collision cross-sections between the cluster ions and He atom were larger than the cross-sections predicted by the presence of a polarization force alone.

Impact of He and H relative depth distributions on the result of sequential He+ and H+ ion implantation and annealing in silicon

Science.gov (United States)

Cherkashin, N.; Daghbouj, N.; Seine, G.; Claverie, A.

2018-04-01

Sequential He++H+ ion implantation, being more effective than the sole implantation of H+ or He+, is used by many to transfer thin layers of silicon onto different substrates. However, due to the poor understanding of the basic mechanisms involved in such a process, the implantation parameters to be used for the efficient delamination of a superficial layer are still subject to debate. In this work, by using various experimental techniques, we have studied the influence of the He and H relative depth-distributions imposed by the ion energies onto the result of the sequential implantation and annealing of the same fluence of He and H ions. Analyzing the characteristics of the blister populations observed after annealing and deducing the composition of the gas they contain from FEM simulations, we show that the trapping efficiency of He atoms in platelets and blisters during annealing depends on the behavior of the vacancies generated by the two implants within the H-rich region before and after annealing. Maximum efficiency of the sequential ion implantation is obtained when the H-rich region is able to trap all implanted He ions, while the vacancies it generated are not available to favor the formation of V-rich complexes after implantation then He-filled nano-bubbles after annealing. A technological option is to implant He+ ions first at such an energy that the damage it generates is located on the deeper side of the H profile.

Transport of heavy ions through matter within ion optical systems

International Nuclear Information System (INIS)

Schwab, T.

1991-04-01

In this thesis for the first time higher-order ion-optical calculations were connected with the whole phase-space changes of the heavy ions in passing through matter. With the developed programs and the newly proposed analytical methods atomic and nuclear interactions of the heavy ions within ion optical systems can be described realistically. The results of this thesis were applied to the conception of the fragment separator (FRS) and to the planning and preparation of experiments at the new GSI accelerator facility. Especially for the description of the ion-optical combination of FRS and the storage ring ESR the developed programs and methods proved to be necessary. A part of the applied theories on the atomic stopping could be confirmed in the framework of this thesis in an experiment with the high-resolving spectrometer SPEC at GANIL. The method of the isotopically pure separation of projectile fragments by means of magnetic analysis and the electronic energy loss could be also experimentally successfully tested at several energies (60-400 MeV/u). Furthermore in this thesis also application-related problems regarding a tumor therapy with heavy ions were solved. A concept for a medical separator (BMS) was developed, which separates light diagnosis beams isotopically purely and beyond improves the energy sharpness by means of an especially shaped (monoenergetic) stopper so that an in-situ range determination is possible with an accuracy of about one millimeter. (orig./HSI) [de

Study of the effect of heavy ion energy on the sensitivity of electronic devices

International Nuclear Information System (INIS)

Raine, M.

2011-01-01

This thesis studies the sensitivity of advanced electronic devices in radiative environments. The work deals with the detailed modeling of the deposited energy induced by heavy-ion in matter, and the influence of taking it into account in the tools simulating the response of irradiated devices. To do so, a simulation chain was developed, combining different calculation codes at various scales. In a first step, the particle-matter interaction code Geant4 is used to model the heavy ion track. These tracks are then implemented in a TCAD simulator, in order to study the response of elementary transistors to these detailed energy deposits. This step is completed with experimental measurements. Finally, the study is extended to the circuit level, by interfacing the heavy ion tracks with a SEE prediction tool. These different steps evidence the need for taking into account the radial extension of the ion track to all simulation levels, to adequately model the response of advanced devices under heavy ion irradiations. (author) [fr

Heavy-Ion-Induced Electronic Desorption of Gas from Metals

CERN Document Server

Molvik, A W; Mahner, E; Kireeff Covo, M; Bellachioma, M C; Bender, M; Bieniosek, F M; Hedlund, E; Krämer, A; Kwan, J; Malyshev, O B; Prost, L; Seidl, P A; Westenskow, G; Westerberg, L

2007-01-01

During heavy-ion operation in several particle accelerators worldwide, dynamic pressure rises of orders of magnitude were triggered by lost beam ions that bombarded the vacuum chamber walls. This ion-induced molecular desorption, observed at CERN, GSI, and BNL, can seriously limit the ion beam lifetime and intensity of the accelerator. From dedicated test stand experiments we have discovered that heavy-ion-induced gas desorption scales with the electronic energy loss (dEe/dx) of the ions slowing down in matter; but it varies only little with the ion impact angle, unlike electronic sputtering.

Induction linacs for heavy ion fusion

International Nuclear Information System (INIS)

Keefe, D.

1986-11-01

Experimental progress to date has strengthened our belief in the soundness and attractiveness of the heavy ion method for fusion. What surprises that have shown up in the laboratory (e.g., in SBTE) have all been of the pleasant kind so far. The systems assessment has supported the view that the heavy ion approach can lead to economically attractive electric power and that a wide variety of options exists in all parameters. The systems work has also been of great help in pointing the way for the research and development activities

European heavy ion ICF driver development

CERN Document Server

Plass, Günther

1996-01-01

Approaches in Europe to heavy ion induced Inertial Confinement Fusion are oriented toward the linac-plus- storage ring technique. Despite the very limited support of this work, technical pro gress was achieved in some important areas. For the immediate future, a substantial intensity upgrade of the GSI accelerator facilities at Darmstadt is being implemented, leading to specific energy depositions of the order of 100 kJ/g and plasma temperatures of 10 to 20 eV. For the longer term, a conceptual design study of a heavy ion based Ignition Facility is being initiated.

New developments in heavy ion fusion

International Nuclear Information System (INIS)

Herrmannsfeldt, W.B.

1984-01-01

Beginning in 1984, the US Department of Energy plans a program aimed at determining the feasibility of using heavy ion accelerators as pellet drivers for Inertial Confinement Fusion (ICF). This paper will describe the events in the field of Heavy Ion Fusion (HIF) that have occurred in the three years since the Lausanne Conference in this series. The emphasis will be on the events leading towards the energy oriented program. In addition to providing an overview of progress in HIF, such a discussion may prove useful for promoters of any ''emerging'' energy technology. (orig.) [de

HIAF: New opportunities for atomic physics with highly charged heavy ions

Science.gov (United States)

Ma, X.; Wen, W. Q.; Zhang, S. F.; Yu, D. Y.; Cheng, R.; Yang, J.; Huang, Z. K.; Wang, H. B.; Zhu, X. L.; Cai, X.; Zhao, Y. T.; Mao, L. J.; Yang, J. C.; Zhou, X. H.; Xu, H. S.; Yuan, Y. J.; Xia, J. W.; Zhao, H. W.; Xiao, G. Q.; Zhan, W. L.

2017-10-01

A new project, High Intensity heavy ion Accelerator Facility (HIAF), is currently being under design and construction in China. HIAF will provide beams of stable and unstable heavy ions with high energies, high intensities and high quality. An overview of new opportunities for atomic physics using highly charged ions and radioactive heavy ions at HIAF is given.

Thermodynamic properties of 3He--4He mixtures near Tlambda

International Nuclear Information System (INIS)

Kakizaki, A.; Satoh, T.

1976-01-01

In order to investigate 3 He impurity effects on the superfluid transition, measurements were made on the thermodynamic quantities, specific heat, thermal expansion coefficients, and pressure dependence of the lambda-transition temperature of three 3 He-- 4 He mixtures and pure 4 He in the neighborhood of the lambda-transition temperature under their saturated vapor pressure. Making use of these measured quantities, it is shown that the so-called Pippard--Buckingham--Fairbank relation holds for 3 He-- 4 He mixtures as well as for pure 4 He, at least in the temperature region of 10 -4 K less than or equal to absolute value (T - T/sub lambda/) less than or equal to 10 -2 K. Based on this, the 3 He impurity effects on the behavior of the specific heat near the lambda-transition are discussed

Heavy ion collisions with the ATLAS detector

International Nuclear Information System (INIS)

Nevski, Pavel

2004-01-01

The ATLAS detector is designed to study high-p T physics in proton-proton collisions at the LHC design luminosity. The detector capabilities for heavy-ion physics are now being evaluated. This paper reports on a preliminary assessment of the baseline ATLAS detector potential for heavy-ion physics. The ATLAS sensitivity to some of the expected signatures from the quark-gluon plasma (e.g. jet quenching, Υ suppression) is discussed. (orig.)

Beam dynamics in heavy ion induction LINACS

International Nuclear Information System (INIS)

Smith, L.

1981-10-01

Interest in the use of an induction linac to accelerate heavy ions for the purpose of providing the energy required to initiate an inertially confined fusion reaction has stimulated a theoretical effort to investigate various beam dynamical effects associated with high intensity heavy ion beams. This paper presents a summary of the work that has been done so far; transverse, longitudinal and coupled longitudinal transverse effects are discussed

Heavy ion drivers for inertial confinement fusion

International Nuclear Information System (INIS)

Keefe, D.

1983-01-01

The advantages of heavy ion beams as a way of delivering the needed energy and power to an inertial fusion target are surveyed. The existing broad technology base of particle accelerators provides an important foundation for designing, costing, and evaluating proposed systems. The sequence of steps needed for the verification of the heavy ion approach is described; recent research results are even more encouraging than had been assumed hitherto

Heavy ion drivers for inertial confinement fusion

International Nuclear Information System (INIS)

Keefe, D.

1983-12-01

The advantages of heavy ion beams as a way of delivering the needed energy and power to an inertial fusion target are surveyed. The existing broad technology base of particle accelerators provides an important foundation for designing, costing, and evaluating proposed systems. The sequence of steps needed for the verification of the heavy ion approach is described; recent research results are even more encouraging than had been assumed hitherto

Composition of heavy ions in solar energetic particle events

International Nuclear Information System (INIS)

Fan, C.Y.; Gloeckler, G.

1983-01-01

The elemental, charge state, and isotopic composition of approximately 1 to 20 MeV per nucleon ions in solar energetic particle (SEP) events was determined and current understanding of the nature of solar and interplanetary processes which may explain the observations are outlined. The composition within individual SEP events may vary both with time and energy, and will in general be different from that in other SEP events. Average values of relative abundances measured in a large number of SEP events, however are found to be roughly energy independent in the approximately 1 to approximately 20 MeV per nucleon range, and show a systematic deviation from photospheric abundances which seem to be organized in terms of the first ionization potential of the ion. Direct measurements of the charge states of SEPs have revealed the surprisingly common presence of energetic He(+) along with heavy ions with typical coronal ionization states. High resolution measurements of isotopic abundance ratios in a small number of SEP events show these to be consistent with the universal composition except for the puzzling overabundance of the SEP Ne-22 relative to this isotopes ratio in the solar wind

Effect of dose on the evolution of cavities in 500-KeV 4He+-ion irradiated nickel

International Nuclear Information System (INIS)

Fenske, G.; Das, S.K.; Kaminsky, M.; Miley, G.H.

1979-01-01

Transmission electron microscopy has been used to investigate the effect of total dose on the depth distribution of cavities (voids or bubbles) in nickel irradiated at 500 0 C with 500-keV 4 He + ions. A transverse sectioning technique, which allows one to obtain the entire depth distribution of cavities and of damage from a single specimen, was utilized. The size, number density and volume fraction of bubbles or voids were measured from the micrographs taken from samples sectioned parallel to the direction of the incident beam. The results for the dose range studied (2 x 10 19 to 1 x 10 21 ions/m 2 ) show that the average cavity diameter, number density, and the volume fraction (i.e., swelling) increases with increasing dose. The peak in the swelling distribution occurs at depths 8 to 15% deeper than the peak in the calculated projected range profile

Elastic and inelastic heavy ion scattering

International Nuclear Information System (INIS)

Toepffer, C.; University of the Witwatersrand, Johannesburg; Richter, A.

1977-02-01

In the field of elastic and inelastic heavy ion scattering, the following issues are dealt with: semiclassical descriptive approximations, optical potentials, barriers, critical radii and angular momenta, excitation functions and the application to superheavy ions and high energies. (WL) [de

Superfluid 3He dynamcs in 3He - 4He solutions

International Nuclear Information System (INIS)

Mejerovich, A.Eh.

1984-01-01

The dynamics of a 3 He- 4 He superfluid solution with two condensates ( 3 He and 4 He) is investigated. Despite the fact that the hydrodynamics of the system is a three-velocity one (two superfluid and one normal velocity), all the thermo- and hydrodynamic functions are determined by the value of only a single linear combination of the velocities. 0n the basis of an analogy between a moving solution and a BCS system with coupling with a non-zero momentum, the dependence of the thermodynamic quantities on the velocities and critical velocities can easily be calculated for both homogeneous and inhomogeneous phases of the solution. In a magnetic field the temperature oscillations (analogue of second sound for a superfluid solution) are accompanied by oscillations of the magnetic moment. The velocity and damping of the spin-temperature waves are determined. The orienting action of a current on the inhomogeneous phases of the solution is discussed. It is shown that the energy and size of the vortexes in a superfluid solution are, due to drag effects, oscillating functions of the effective mass of the 3 He quasirartictes (pressure). At a pressure of the order of 10 atm a first order transition should take place in the vortex line which is accompanied by an abrupt change of the circulations of superfluid velocity of 3 He for a fixed circulation of the 4 He velocity

Fast heavy-ion radiation damage of glycine in aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Nomura, Shinji [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Tsuchida, Hidetsugu, E-mail: tsuchida@nucleng.kyoto-u.ac.jp [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan); Furuya, Ryosuke [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Majima, Takuya; Itoh, Akio [Department of Nuclear Engineering, Kyoto University, Kyoto 615-8530 (Japan); Quantum Science and Engineering Center, Kyoto University, Uji 611-0011 (Japan)

2016-12-15

Fast heavy-ion radiolysis of biomolecules in aqueous solution is investigated for an atomistic understanding of radiation damage to normal cells during heavy-particle beam therapy. The smallest amino acid glycine was used as a model biomaterial. Microjets of aqueous glycine solutions under vacuum were irradiated with 4.0-MeV carbon ions corresponding to energies in the Bragg peak region. To understand the effects of the water environment on molecular damage, the yield of glycine dissociation was measured by secondary ion mass spectroscopy. The yield was significantly reduced relative to gas-phase glycine targets. This implies that the numerous water molecules surrounding a single glycine molecule act as a buffer that suppresses dissociation. This is an environmental effect similar to that observed for other biomolecular cluster targets.

Origin and Properties of Quiet-time 0.11–1.28 MeV Nucleon{sup −1} Heavy-ion Population Near 1 au

Energy Technology Data Exchange (ETDEWEB)

Dayeh, M. A.; Desai, M. I.; Ebert, R. W. [Space Science and Engineering Division, Southwest Research Institute, San Antonio, TX 78238 (United States); Mason, G. M. [Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723 (United States); Farahat, A., E-mail: maldayeh@swri.edu [Department of Physics, College of Applied and Supporting Studies, King Fahd University of Petroleum and Minerals, Dhahran 31261 (Saudi Arabia)

2017-02-01

Using measurements from the Advanced Composition Explorer /Ultra-Low Energy Isotope Spectrometer near 1 au, we surveyed the composition and spectra of heavy ions (He-through-Fe) during quiet times from 1998 January 1 to 2015 December 31 at suprathermal energies between ∼0.11 and ∼1.28 MeV nucleon{sup −1}. The selected time period covers the maxima of solar cycles 23 and 24 and the extended solar minimum in between. We find the following. (1) The number of quiet hours in each year correlates well with the sunspot number, year 2009 was the quietest for about 82% of the time. (2) The composition of the quiet-time suprathermal heavy-ion population ({sup 3}He, C-through-Fe) correlates well with the level of solar activity, exhibiting SEP-like composition signatures during solar maximum, and CIR- or solar wind-like composition during solar minimum. (3) The heavy-ion (C–Fe) spectra exhibit suprathermal tails at energies of 0.11–0.32 MeV nucleon{sup −1} with power-law spectral indices ranging from 1.40 to 2.97. Fe spectra soften (steepen, i.e., spectral index increases) smoothly with increasing energies compared with Fe, indicating a rollover behavior of Fe at higher energies (0.45–1.28 MeV nucleon{sup −1}). (4) Spectral indices of Fe and O do not appear to exhibit clear solar cycle dependence. (2) and (3) imply that during IP quiet times and at energies above ∼0.1 MeV nucleon{sup −1}, the IP medium is dominated by material from prior solar and interplanetary events. We discuss the implications of these extended observations in the context of the current understanding of the suprathermal ion population near 1 au.

X-ray-induced thinning of 3He and 3He/4He mixture films

International Nuclear Information System (INIS)

Penanen, Konstantin; Fukuto, Masafumi; Silvera, Isaac F.; Pershan, Peter

2000-01-01

Films of isotopic mixtures of helium have been studied using x-ray specular reflectivity techniques. In contrast with superfluid 4 He films, x-ray exposure causes a reduction in the thickness of 4 He films above the superfluid transition as well as films of pure 3 He and 3 He/ 4 He mixtures. One proposed model that could account for this effect is a charging model, in which thinning is caused by electrostatic pressure of free charges that accumulate on the helium surface. Unfortunately, this model is not fully consistent with all of the experimental observations. A localized heating model, in which indirect heating of the film causes it to thin would explain the data if there were dissipative film flow in the 3 He/ 4 He mixtures at temperatures where the bulk is superfluid. We argue that various published experimental results suggest such an effect. In this model, film thinning data for dilute 3 He/ 4 He films indicates dissipation that is linear in 3 He content of the film over two orders of magnitude

Interactions of heavy ions with biomolecules: a dynamical microscopic approach

International Nuclear Information System (INIS)

Zhang Fengshou; Beijing Radiation Center, Beijing; National Laboratory of Heavy Ion Accelerator of Lanzhou, Lanzhou

2006-01-01

The status of studying biology system therapy with X-rays, γ-rays, neutron, proton, and heavy ions is reviewed. The depth dose profile, called Bragg profile, makes heavy ion an ideal tool for radiotherapy. The physical process of therapy with heavy ions is analyzed and a 3-step interaction processes of heavy ions with biomolecules is proposed, that is, nuclear fragmentation in nuclear interaction, electron excitation in Coulomb interaction, and the biomolecules relaxation in surroundings, finally leads to a new structure of biomolecule. Since this physical process is the base of the following chemical process and biological process, a dynamical microscopic approach is strongly demanded to be built. (authors)

Heavy ion inertial fusion - an overview

International Nuclear Information System (INIS)

Lawson, J.D.

1983-09-01

Energetic heavy ions represent an alternative to laser light and light ions as ''drivers'' for supplying energy for inertial confinement fusion. To induce ignition of targets containing thermonuclear fuel, an energy of several megajoules has to be focused on to a target with radius a few millimetres in a time of some tens of nanoseconds. Serious study of the use of heavy ion drivers for producing useful power in this way has been underway for seven years, though funding has been at a low level. In this paper the requirements for targets, accelerator, and reactor vessel for containing the thermonuclear explosion are surveyed, and some of the problems to be solved before the construction of a power station can realistically be contemplated are discussed. (author)

Dissociation of fast HeH+ ions in foils and gases

International Nuclear Information System (INIS)

Gemmell, D.S.; Cooney, P.J.; Pietsch, W.J.; Ratkowski, A.J.; Vager, Z.

1978-01-01

To gain understanding of phenomena observed when very simple light diatomic ions are incident at high velocities upon thin foils and gaseous targets, an extensive set of measurements on the dissociation products arising from beams of HeH + was made. Experimental and calculated joint distributions in energy and angle for protons emerging (near the beam direction) from an 85-A carbon foil bombarded by 2.0-MeV HeH + ions are presented

Improvement of herbage by heavy ion beams

International Nuclear Information System (INIS)

Xie Hongmei; Hao Jifang; Wei Zengquan; Xie Zhongkui; Li Fengqin; Wang Yajun

2004-01-01

Herbage seeds of legume and grass were irradiated in penetration by 80 MeV/u 20 Ne 10+ ions. The results of field tests and observations of the root-tip cells showed that growth of the seedling was obviously weakened with increasing doses. Frequencies of chromosomal aberration and micronucleus increased significantly with increasing doses. According to the field growth tests, radiation sensitivity of grass herbage to the heavy ion beams was much higher than leguminous herbage, and suitable dose of the heavy ion irradiation for the grass and leguminous herbage is 20-30 Gy and 150 Gy, respectively

Molecular dynamics simulations of ion range profiles for heavy ions in light targets

Energy Technology Data Exchange (ETDEWEB)

Lan, C. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Xue, J.M. [State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Zhang, Y., E-mail: Zhangy1@ornl.gov [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Morris, J.R. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Zhu, Z. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Gao, Y.; Wang, Y.G.; Yan, S. [State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Weber, W.J. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2012-09-01

The determination of stopping powers for slow heavy ions in targets containing light elements is important to accurately describe ion-solid interactions, evaluate ion irradiation effects and predict ion ranges for device fabrication and nuclear applications. Recently, discrepancies of up to 40% between the experimental results and SRIM (Stopping and Range of Ions in Matter) predictions of ion ranges for heavy ions with medium and low energies (<{approx}25 keV/nucleon) in light elemental targets have been reported. The longer experimental ion ranges indicate that the stopping powers used in the SRIM code are overestimated. Here, a molecular dynamics simulation scheme is developed to calculate the ion ranges of heavy ions in light elemental targets. Electronic stopping powers generated from both a reciprocity approach and the SRIM code are used to investigate the influence of electronic stopping on ion range profiles. The ion range profiles for Au and Pb ions in SiC and Er ions in Si, with energies between 20 and 5250 keV, are simulated. The simulation results show that the depth profiles of implanted ions are deeper and in better agreement with the experiments when using the electronic stopping power values derived from the reciprocity approach. These results indicate that the origin of the discrepancy in ion ranges between experimental results and SRIM predictions in the low energy region may be an overestimation of the electronic stopping powers used in SRIM.

Expression profiles of mRNA after exposure yeast and rice to heavy-ion radiation

International Nuclear Information System (INIS)

Iwahashi, Hitoshi; Mizukami, Satomi; Nojima, Kumie

2005-01-01

We have studied expression profiles of mRNA after exposure yeast cells to heavy-ion radiation. Yeast cells was exposed by heavy-ion radiation with the levels of 6, 12, 25, 50, and 100 Gy. We could confirm the reproducibility of physiological state of yeast cells under the experimental conditions by DNA microarray. We could also confirm the reproducibility of viability of yeast cells after exposure to heavy-ion radiation. We thus applied yeast cells exposed with 25 Gy was applied to DNA microarray analysis. The strongly induced genes were HUG1 RAR4 RNR2 for DNA repairing genes and GLC3 GSY1 for energy metabolism genes. (author)

Current experimental situation in heavy-ion reactions

International Nuclear Information System (INIS)

Scott, D.K.

1978-06-01

A detailed survey of the present experimental situation in heavy-ion physics is presented. The discussion begins by considering the simple excitation of discrete states in elastic scattering, transfer, and compound-nucleus reactions; it then turns to more drastic perturbations of the nucleus high in the continuum through fusion, fission, and deeply inelastic scattering, and concludes with the (possibly) limiting asymptotic phenomena of relativistic heavy-ion collisions. 138 figures, 5 tables, 451 references

Now day methods for heavy ion monitoring

International Nuclear Information System (INIS)

Luk'yanov, S.M.; Penionzhkevich, Yu.Eh.; Chubaryan, G.G.

1984-01-01

Up-to-date methods for identification of products yield as a result of heavy ion interaction with nuclei are described. Monitoring of total ionization has been realized by gas-filled ionization chambers semiconductor detectors, scintillators. A method for specific ionization loss monitoring and time-of-flight technique for heavy-ion mass identification are considered. Advantages of the method for identification of nuclear reaction prodUcts by means of a magnetic analyzer are displayed

Swift Heavy Ion Induced Modification of Aliphatic Polymers

OpenAIRE

Hossain, Umme Habiba

2015-01-01

In this thesis, the high energy heavy ion induced modification of aliphatic polymers is studied. Two polymer groups, namely polyvinyl polymers (PVF, PVAc, PVA and PMMA) and fluoropolymers (PVDF, ETFE, PFA and FEP) were used in this work. Polyvinyl polymers were investigated since they will be used as insulating materials in the superconducting magnets of the new ion accelerators of the planned International Facility for Antiproton and Ion Research (FAIR) at the GSI Helmholtz-Centre of Heavy I...