WorldWideScience

Sample records for charged particle irradiation

  1. Charge collection studies in irradiated HV-CMOS particle detectors

    Science.gov (United States)

    Affolder, A.; Andelković, M.; Arndt, K.; Bates, R.; Blue, A.; Bortoletto, D.; Buttar, C.; Caragiulo, P.; Cindro, V.; Das, D.; Dopke, J.; Dragone, A.; Ehrler, F.; Fadeyev, V.; Galloway, Z.; Gorišek, A.; Grabas, H.; Gregor, I. M.; Grenier, P.; Grillo, A.; Hommels, L. B. A.; Huffman, T.; John, J.; Kanisauskas, K.; Kenney, C.; Kramberger, G.; Liang, Z.; Mandić, I.; Maneuski, D.; McMahon, S.; Mikuž, M.; Muenstermann, D.; Nickerson, R.; Perić, I.; Phillips, P.; Plackett, R.; Rubbo, F.; Segal, J.; Seiden, A.; Shipsey, I.; Song, W.; Stanitzki, M.; Su, D.; Tamma, C.; Turchetta, R.; Vigani, L.; Volk, J.; Wang, R.; Warren, M.; Wilson, F.; Worm, S.; Xiu, Q.; Zavrtanik, M.; Zhang, J.; Zhu, H.

    2016-04-01

    Charge collection properties of particle detectors made in HV-CMOS technology were investigated before and after irradiation with reactor neutrons. Two different sensor types were designed and processed in 180 and 350 nm technology by AMS. Edge-TCT and charge collection measurements with electrons from 90Sr source were employed. Diffusion of generated carriers from undepleted substrate contributes significantly to the charge collection before irradiation, while after irradiation the drift contribution prevails as shown by charge measurements at different shaping times. The depleted region at a given bias voltage was found to grow with irradiation in the fluence range of interest for strip detectors at the HL-LHC. This leads to large gains in the measured charge with respect to the one before irradiation. The increase of the depleted region was attributed to removal of effective acceptors. The evolution of depleted region with fluence was investigated and modeled. Initial studies show a small effect of short term annealing on charge collection.

  2. Local phase transformation in alloys during charged-particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lam, N.Q.; Okamoto, P.R.

    1984-10-01

    Among the various mechanisms and processes by which energetic irradiation can alter the phase stability of alloys, radiation-induced segregation is one of the most important phenomena. Radiation-induced segregation in alloys occurs as a consequence of preferential coupling between persistent fluxes of excess defects and solute atoms, leading to local enrichment or depletion of alloying elements. Thus, this phenomenon tends to drive alloy systems away from thermodynamic equilibrium, on a local scale. During charged-particle irradiations, the spatial nonuniformity in the defect production gives rise to a combination of persistent defect fluxes, near the irradiated surface and in the peak-damage region. This defect-flux combination can modify the alloy composition in a complex fashion, i.e., it can destabilize pre-existing phases, causing spatially- and temporally-dependent precipitation of new metastable phases. The effects of radiation-induced segregation on local phase transformations in Ni-based alloys during proton bombardment and high-voltage electron-microscope irradiation at elevated temperatures are discussed.

  3. Standard Practice for Measurement of Mechanical Properties During Charged-Particle Irradiation

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1996-01-01

    1.1 This practice covers the performance of mechanical tests on materials being irradiated with charged particles. These tests are designed to simulate or provide understanding of, or both, the mechanical behavior of materials during exposure to neutron irradiation. Practices are described that govern the test material, the particle beam, the experimental technique, and the damage calculations. Reference should be made to other ASTM standards, especially Practice E 521. Procedures are described that are applicable to creep and creep rupture tests made in tension and torsion test modes. 1.2 The word simulation is used here in a broad sense to imply an approximation of the relevant neutron irradiation environment. The degree of conformity can range from poor to nearly exact. The intent is to produce a correspondence between one or more aspects of the neutron and charged particle irradiations such that fundamental relationships are established between irradiation or material parameters and the material respons...

  4. Cell and tissue kinetics of the subependymal layer in mouse brain following heavy charged particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Manley, N.B.; Fabrikant, J.I.; Alpen, E.L.

    1988-12-01

    The following studies investigate the cellular response and cell population kinetics of the subependymal layer in the mouse brain exposed to heavy charged particle irradiation. Partial brain irradiation with helium and neon ions was confined to one cortex of the brain. Both the irradiated and the unirradiated contralateral cortex showed similar disturbances of the cell and tissue kinetics in the subependymal layers. The irradiated hemisphere exhibited histological damage, whereas the unirradiated side appeared normal histologically. This study concerns the cell population and cell cycle kinetics of the subependymal layer in the mouse brain, and the effects of charged particle irradiations on this cell population. Quantitative high resolution autoradiography was used to study the kinetic parameters in this cell layer. This study should help in understanding the effects of these high-energy heavy ions on normal mammalian brain tissue. The response of the mammalian brain exposure to charged particle ionizing radiation may be extremely variable. It varies from minimal physiological changes to overt tissue necrosis depending on a number of factors such as: the administered dose, dose-rate, the volume of the irradiated tissue, and the biological end-point being examined.

  5. Influence of penetration controlled irradiation with charged particles on tobacco pollen

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Hiroshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Dept. of Radiation Research for Environment and Resources; Tanaka, Atsushi; Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Advanced Science Research Center; Inoue, Masayoshi [Kyoto Prefectural Univ. (Japan). Faculty of Agriculture

    1997-09-01

    To investigate the effect of local irradiation on biological systems, an apparatus for penetration controlled irradiation with charged particles was set up. By comparison of ranges of 1.5 MeV/u He{sup 2+} between the theoretically calculated ranges and the practical ranges using RCD dosimeter, it was demonstrated that the range of particles could be controlled linearly by changing the distance from the beam window in the atmosphere to a target. In addition, the penetration controlled irradiation of tobacco pollen increased the frequency of `leaky pollen`. The increased frequency of the leaky pollen suggests that a damage in the pollen envelope would be induced at the range-end. (orig.)

  6. A model of knock-out of oxygen by charged particle irradiation of Bi-2212

    International Nuclear Information System (INIS)

    A model of knock-out of oxygen by charged particle (α and proton) irradiation of Bi2Sr2CaCu2O8+x (Bi-2212) is proposed on the basis of Monte Carlo TRIM calculations. In Bi-2212, the loosely bound excess oxygen is vulnerable to be displaced by particle irradiation. Binding energy and hence, displacement energy of this loosely bound excess oxygen is less compared to that of stoichiometric lattice bound oxygen and other atoms. The displaced or knocked out oxygen goes to pores or intergranular region and generates large pressure inside the sample. Because of porosity of the material, this displaced oxygen diffuses out and there is a net reduction of oxygen content of the sample. The irradiation induced oxygen knock-out is dominant in the bulk where nonionizing energy loss is maximum. (author). 29 refs., 1 fig., 3 tabs

  7. Water and sludge treatment device provided with a system for irradiating by accelerated charged particles

    International Nuclear Information System (INIS)

    Treatment system for a fluid made up of water and sludge, provided with a system for irradiating the fluid by a beam of accelerated charged particles comprising means for obtaining a constant flow of the fluid to be treated, facilities for monitoring this flow, an irradiation channel located on the path of the beam, in which the fluid to be treated can flow, a portion of this channel having at least one window transparent to the beam of accelerated particles. A safety system associated with the system for monitoring the characteristics of the beam and with the system for monitoring the flow of the fluid to be treated, stops the flow of the fluid and the recycling of the fluid defectively treated

  8. Neutron irradiation of bacteria in the presence and absence of secondary charged-particle equilibrium

    International Nuclear Information System (INIS)

    The survival rate of Shigella flexneri has been measured for irradiation with 7-MeV neutrons in the presence and absence of secondary charged-particle equilibrium. The data were analyzed to assess the separate response of the cells to the knock-on proton and α-particle plus heavy-recoil components. A detailed consideration of the frequency of α-particle and heavy-recoil traversals of the cell has been made to explain our results, and in addition we have applied this approach to analyze the earlier results obtained with mammalian cells. We conclude that of the secondary charged-particles produced by the Hammersmith neutron beam, the highest LET particles, the heavy-recoil nuclei, contribute a minor proportion of damage to bacteria but form a major contribution of damage in mammalian cells. The reduction in oxygen enhancement ratio (OER) with neutrons compared with low LET radiation for mammalian cells is due almost entirely to the influence of the heavy recoils and the contribution of the α-particle and knock-on protons to the reduction of the OER is relatively minor. For Shigella flexneri the α particles and heavy recoils make approximately equal contributions to the reduction in OER

  9. Bystander-induced apoptosis and premature differentiation in primary urothelial explants after charged particle microbeam irradiation

    International Nuclear Information System (INIS)

    The ureter primary explant technique was developed to study bystander effects under in vivo like conditions where stem and differentiated cells are present. Irradiation was performed with a 3He2+ charged particle microbeam available at the Gray Cancer Institute, with high (∼2 μm) precision. Tissue sections from porcine ureters were pre-irradiated with the microbeam at a single location with 103He2+ particles (5 MeV; LET 70 keV.μm-1). After irradiation, the tissue section was incubated for 7 days, thus allowing the explant outgrowth to form. Total cellular damage (total fraction of micronucleated and apoptotic cells) was measured according to morphological criteria. Apoptosis was also assessed using a 3'-OH DNA end-labelling technique. Premature differentiation was estimated using antibodies to uroplakin III, a specific marker of terminal urothelial differentiation. Results of our experiments demonstrated a significant bystander-induced differentiation and a less significant increase in apoptotic and micronucleated cells. A hypothesis based on the protective nature of the bystander effect is proposed. (author)

  10. Experimental study of the nucleation and growth of c-component loops under charged particle irradiations of recrystallized Zircaloy-4

    International Nuclear Information System (INIS)

    Recrystallized zirconium alloys, used as structural materials for the Pressurized Water Reactor fuel assembly, undergo under neutron irradiation induced stress free growth which accelerates for high irradiation doses. This acceleration is correlated with the formation of c-component vacancy dislocation loops in the basal plane. Since these defects are responsible for breakaway growth of recrystallized zirconium alloys, it is of prime importance to know the various factors that can affect their nucleation and growth. In the present work, two types of charged particle irradiations were conducted on recrystallized Zircaloy-4 samples in order to study c-component loops. A 2 MeV proton irradiation was performed up to a dose of 11.5 dpa at 623 K, and 600 keV Zr ion irradiations were carried out at 573 K up to 7 dpa. For the first time after those charged particle irradiations, c-component loops were observed by Transmission Electron Microscopy. It has been shown that under Zr ion irradiation they start to nucleate and grow beyond a threshold dose as for neutron irradiation. The differences in the c-component loop microstructure are discussed for both ion irradiations and compared to the microstructure observed after neutron irradiation. Furthermore, it is shown that after proton irradiation the irradiated layer exhibits a misfit strain which is consistent with the irradiation induced growth of recrystallized zirconium alloys.

  11. Experimental study of the nucleation and growth of c-component loops under charged particle irradiations of recrystallized Zircaloy-4

    Energy Technology Data Exchange (ETDEWEB)

    Tournadre, L., E-mail: lea.tournadre@cea.fr [CEA-DEN, Section for Applied Metallurgy Research, 91191 Gif-sur-Yvette, Cedex (France); Onimus, F.; Bechade, J.-L. [CEA-DEN, Section for Applied Metallurgy Research, 91191 Gif-sur-Yvette, Cedex (France); Gilbon, D. [CEA-DEN, Nuclear Material Department, 91191 Gif-sur-Yvette, Cedex (France); Cloue, J.-M.; Mardon, J.-P. [AREVA NP SAS Fuel Business Unit 10, Rue Juliette Recamier 69456, Lyon Cedex 06 (France); Feaugas, X. [Laboratoire d' Etude des Materiaux en Milieux Agressifs (LEMMA), Universite de La Rochelle, 17042 La Rochelle Cedex 1 (France); Toader, O. [Michigan Ion Beam Laboratory (MIBL), University of Michigan, Ann Arbor, MI 48109 (United States); Bachelet, C. [Centre de Spectrometrie Nucleaire et de Spectroscopie de Masse (CSNSM), Universite Paris-Sud 11, 91405 Orsay Campus (France)

    2012-06-15

    Recrystallized zirconium alloys, used as structural materials for the Pressurized Water Reactor fuel assembly, undergo under neutron irradiation induced stress free growth which accelerates for high irradiation doses. This acceleration is correlated with the formation of c-component vacancy dislocation loops in the basal plane. Since these defects are responsible for breakaway growth of recrystallized zirconium alloys, it is of prime importance to know the various factors that can affect their nucleation and growth. In the present work, two types of charged particle irradiations were conducted on recrystallized Zircaloy-4 samples in order to study c-component loops. A 2 MeV proton irradiation was performed up to a dose of 11.5 dpa at 623 K, and 600 keV Zr ion irradiations were carried out at 573 K up to 7 dpa. For the first time after those charged particle irradiations, c-component loops were observed by Transmission Electron Microscopy. It has been shown that under Zr ion irradiation they start to nucleate and grow beyond a threshold dose as for neutron irradiation. The differences in the c-component loop microstructure are discussed for both ion irradiations and compared to the microstructure observed after neutron irradiation. Furthermore, it is shown that after proton irradiation the irradiated layer exhibits a misfit strain which is consistent with the irradiation induced growth of recrystallized zirconium alloys.

  12. Dose distribution of secondary charged particles in multilayer samples irradiated by gamma quanta

    International Nuclear Information System (INIS)

    The calculations of the absorbed dose from secondary electrons and positrons are performed for the fiber light pipe irradiated by gamma-quanta in the energy range 0.2-10 MeV. The light pipe comprises the cylindrical quartz glass layer surrounded by the light-reflective silicone coating. The transmission of gamma-quanta through the light pipe is considered for the cases of two protective shells and without ones. The calculations of the absorbed dose in the light pipe is carried out by means of the FORTRAN program based on the Monte Carlo method. It is shown that the dose of secondary charged particles (mainly electrons) in the light pipe depends significantly on the energy of primary gamma-quanta and increases considerably with protective polymeric shells

  13. Difference in behaviour between Bi-2212 and Bi-2223 superconductors towards charged particle irradiation

    International Nuclear Information System (INIS)

    Particle irradiation is generally known to cause a decrease in Tc in both conventional and high Tc superconductors. But it was observed that there is an increase in Tc by 20 MeV α-irradiation on polycrystalline Bi-2212 superconductor of Tc=65K (over doped with oxygen) monotonically with dose after 1x1015α/cm2 and the increase appears to be due to knock-out of oxygen

  14. The effect of charge collection recovery in silicon p-n junction detectors irradiated by different particles

    International Nuclear Information System (INIS)

    The recovery of the charge collection efficiency (CCE) at low temperatures, the so-called 'Lazarus effect', was studied in Si detectors irradiated by fast reactor neutrons, by protons of medium and high energy, by pions and by gamma-rays. The experimental results show that the Lazarus effect is observed: (a) after all types of irradiation; (b) before and after space charge sign inversion; (c) only in detectors that are biased at voltages resulting in partial depletion at room temperature. The experimental temperature dependence of the CCE for proton-irradiated detectors shows non-monotonic behaviour with a maximum at a temperature defined as the CCE recovery temperature. The model of the effect for proton-irradiated detectors agrees well with that developed earlier for detectors irradiated by neutrons. The same midgap acceptor-type and donor-type levels are responsible for the Lazarus effect in detectors irradiated by neutrons and by protons. A new, abnormal 'zigzag'-shaped temperature dependence of the CCE was observed for detectors irradiated by all particles (neutrons, protons and pions) and by an ultra-high dose of γ-rays, when operating at low bias voltages. This effect is explained in the framework of the double-peak electric field distribution model for heavily irradiated detectors. The redistribution of the space charge region depth between the depleted regions adjacent to p+ and n+ contacts is responsible for the 'zigzag'- shaped curves. It is shown that the CCE recovery temperature increases with reverse bias in all detectors, regardless of the type of radiation

  15. The effect of charge collection recovery in silicon p-n junction detectors irradiated by different particles

    Energy Technology Data Exchange (ETDEWEB)

    Verbitskaya, E. E-mail: elena.verbitskaya@pop.ioffe.rssi.ru; Abreu, M.; Anbinderis, P.; Anbinderis, T.; D' Ambrosio, N.; Boer, W. de; Borchi, E.; Borer, K.; Bruzzi, M.; Buontempo, S.; Casagrande, L.; Chen, W.; Cindro, V.; Dezillie, B.; Dierlamm, A.; Eremin, V.; Gaubas, E.; Gorbatenko, V.; Granata, V.; Grigoriev, E.; Grohmann, S.; Hauler, F.; Heijne, E.; Heising, S.; Hempel, O.; Herzog, R.; Haerkoenen, J.; Ilyashenko, I.; Janos, S.; Jungermann, L.; Kalesinskas, V.; Kapturauskas, J.; Laiho, R.; Li, Z.; Mandic, I.; De Masi, Rita; Menichelli, D.; Mikuz, M.; Militaru, O.; Niinikoski, T.O.; O' Shea, V.; Pagano, S.; Palmieri, V.G.; Paul, S.; Perea Solano, B.; Piotrzkowski, K.; Pirollo, S.; Pretzl, K.; Rato Mendes, P.; Ruggiero, G.; Smith, K.; Sonderegger, P.; Sousa, P.; Tuominen, E.; Vaitkus, J.; Da Via, C.; Wobst, E.; Zavrtanik, M

    2003-11-21

    The recovery of the charge collection efficiency (CCE) at low temperatures, the so-called 'Lazarus effect', was studied in Si detectors irradiated by fast reactor neutrons, by protons of medium and high energy, by pions and by gamma-rays. The experimental results show that the Lazarus effect is observed: (a) after all types of irradiation; (b) before and after space charge sign inversion; (c) only in detectors that are biased at voltages resulting in partial depletion at room temperature. The experimental temperature dependence of the CCE for proton-irradiated detectors shows non-monotonic behaviour with a maximum at a temperature defined as the CCE recovery temperature. The model of the effect for proton-irradiated detectors agrees well with that developed earlier for detectors irradiated by neutrons. The same midgap acceptor-type and donor-type levels are responsible for the Lazarus effect in detectors irradiated by neutrons and by protons. A new, abnormal 'zigzag'-shaped temperature dependence of the CCE was observed for detectors irradiated by all particles (neutrons, protons and pions) and by an ultra-high dose of {gamma}-rays, when operating at low bias voltages. This effect is explained in the framework of the double-peak electric field distribution model for heavily irradiated detectors. The redistribution of the space charge region depth between the depleted regions adjacent to p{sup +} and n{sup +} contacts is responsible for the 'zigzag'- shaped curves. It is shown that the CCE recovery temperature increases with reverse bias in all detectors, regardless of the type of radiation.

  16. Track structure approach to the calculation of peak 5a to peak 5 (TLD-100) relative intensities following heavy charged particle irradiation

    International Nuclear Information System (INIS)

    A track structure approach to the calculation of the relative strength of localised and de-localised recombination mechanisms leading to composite glow peak 5 in LiF:Mg,Ti following heavy charged particle irradiation is described. (authors)

  17. Charged particle's flux measurement from PMMA irradiated by 80 MeV/u carbon ion beam

    CERN Document Server

    Agodi, C; Bellini, F; Cirrone, G A P; Collamati, F; Cuttone, G; De Lucia, E; De Napoli, M; Di Domenico, A; Faccini, R; Ferroni, F; Fiore, S; Gauzzi, P; Iarocci, E; Marafini, M; Mattei, I; Muraro, S; Paoloni, A; Patera, V; Piersanti, L; Romano, F; Sarti, A; Sciubba, A; Vitale, E; Voena, C

    2012-01-01

    Hadrontherapy is an emerging technique in cancer therapy that uses beams of charged particles. To meet the improved capability of hadrontherapy in matching the dose release with the cancer position, new dose monitoring techniques need to be developed and introduced into clinical use. The measurement of the fluxes of the secondary particles produced by the hadron beam is of fundamental importance in the design of any dose monitoring device and is eagerly needed to tune Monte Carlo simulations. We report the measurements done with charged secondary particles produced from the interaction of a 80 MeV/u fully stripped carbon ion beam at the INFN Laboratori Nazionali del Sud, Catania, with a Poly-methyl methacrylate target. Charged secondary particles, produced at 90$\\degree$ with respect to the beam axis, have been tracked with a drift chamber, while their energy and time of flight has been measured by means of a LYSO scintillator. Secondary protons have been identified exploiting the energy and time of flight in...

  18. Charged-particle acceleration through laser irradiation of thin foils at Prague Asterix Laser System

    International Nuclear Information System (INIS)

    Thin foils, 0.5–50 μm in thickness, have been irradiated in vacuum at Prague Asterix Laser System in Prague using 1015–16 W cm−2 laser intensity, 1315 nm wavelength, 300 ps pulse duration and different focal positions. Produced plasmas from metals and polymers films have been monitored in the forward and backward directions. Ion and electron accelerations have been investigated by using Thomson parabola spectrometer, x-ray streak camera, ion collectors and SiC semiconductor detectors, the latter employed in time-of-flight configuration. Ion acceleration up to about 3 MeV per charge state was measured in the forward direction. Ion and electron emissions were detected at different angles as a function of the irradiation conditions. (paper)

  19. Short DNA Fragments are a Hallmark of Heavy Charged Particle Irradiation and May Be Underling Their Greater Therapeutic Efficacy

    Directory of Open Access Journals (Sweden)

    Dalong ePang

    2016-06-01

    Full Text Available Growing interest in proton and heavy ion therapy has reinvigorated research into the fundamental biological mechanisms underlying the therapeutic efficacy of charged particle radiation. To improve our understanding of the greater biological effectiveness of high-LET radiations, we have investigated DNA double strand breaks (DSB following exposure of plasmid DNA to low-LET Co-60 gamma photon and electron irradiation and to high-LET Beryllium and Argon ions with atomic force microscopy (AFM. The sizes of DNA fragments following radiation exposure were individually measured to construct fragment size distributions from which the DSB per DNA molecule and DSB spatial distributions were derived. We report that heavy charged particles induce a significantly larger proportion of short DNA fragments in irradiated DNA molecules, reflecting densely and clustered damage patterns of high-LET energy depositions. We attribute the enhanced short DNA fragmentation following high-LET radiations as an important determinant of the observed, enhanced biological effectiveness of high-LET irradiations.

  20. Short DNA Fragments Are a Hallmark of Heavy Charged-Particle Irradiation and May Underlie Their Greater Therapeutic Efficacy

    Science.gov (United States)

    Pang, Dalong; Chasovskikh, Sergey; Rodgers, James E.; Dritschilo, Anatoly

    2016-01-01

    Growing interest in proton and heavy ion therapy has reinvigorated research into the fundamental biological mechanisms underlying the therapeutic efficacy of charged-particle radiation. To improve our understanding of the greater biological effectiveness of high-LET radiations, we have investigated DNA double-strand breaks (DSBs) following exposure of plasmid DNA to low-LET Co-60 gamma photon and electron irradiation and to high-LET Beryllium and Argon ions with atomic force microscopy. The sizes of DNA fragments following radiation exposure were individually measured to construct fragment size distributions from which the DSB per DNA molecule and DSB spatial distributions were derived. We report that heavy charged particles induce a significantly larger proportion of short DNA fragments in irradiated DNA molecules, reflecting densely and clustered damage patterns of high-LET energy depositions. We attribute the enhanced short DNA fragmentation following high-LET radiations as an important determinant of the observed, enhanced biological effectiveness of high-LET irradiations. PMID:27376024

  1. Annealing effects on charge collection efficiency of an electron-irradiated 4H-SiC particle detector

    International Nuclear Information System (INIS)

    Thermal annealing effects on the charge collection efficiency (CCE) of an electron-irradiated 4H silicon carbide Schottky barrier diode (SBD) particle detector have been studied. The CCE of the SBD detector is degraded by 1 MeV electrons with a fluence of 1×1015 cm-2. The degraded CCE recovers with low temperature annealing up to 300°C. However, CCE starts to decrease again by annealing at 350°C. Conventional electrical characterization such as current and capacitance vs voltage measurements, deep level transient spectroscopy used to understand the CCE variation on annealing is discussed. (author)

  2. Exoemission of charged particles from the surface of irradiated high-temperature superconducting ceramics

    International Nuclear Information System (INIS)

    The present communication reports the results of the study of the samples of YBa2Cu3O7 ceramics with a density of 5.4 g/cm3, composed of one phase with Tc = 92 K in the form of 1 mm thick tablets 10 mm in diameter. Part of the samples was obtained in the air by the use of gamma-quanta (Cobalt-60), the absorbed dose was 106 rad. The design of the facility for recording the thermostimulated exoemission (TSE) spectra of positive and negative particles allowed the measurements to be made in the vacuum of 10-8 Tor at a heating rate of 0.1 K [4]. Part of the experiments was made using non-irradiated ceramics which were spalled in a vacuum chamber shortly before recording the TSE spectra

  3. Theoretical and experimental radiation effectiveness of the free radical dosimeter alanine to irradiation with heavy charged particles

    DEFF Research Database (Denmark)

    Hansen, Jørgen-Walther; Olsen, K. J.

    1985-01-01

    Dose-response characteristics have been measured for the crystalline amino acid L-.alpha.-alanine irradiated with ion beams of 6 and 16 MeV protons, 20 MeV .alpha. particles, 21 MeV7Li ions, 64 MeV16O ions, and 80 MeV32S ions. The experimental radiation effectiveness (RE) with reference to low......-LET radiations of 60Co .gamma. rays, 4 and 16 MV X rays, and 6, 10, and 20 MeV electrons was compared with theoretical RE values derived from a model based on track structure theory of heavy charged particles. The ion beams covered a range in initial LET of 27-20,200 MeVcm2/g, and the experimental RE decreased...

  4. Relative biological effectiveness in canine osteosarcoma cells irradiated with accelerated charged particles

    Science.gov (United States)

    Maeda, Junko; Cartwright, Ian M.; Haskins, Jeremy S.; Fujii, Yoshihiro; Fujisawa, Hiroshi; Hirakawa, Hirokazu; Uesaka, Mitsuru; Kitamura, Hisashi; Fujimori, Akira; Thamm, Douglas H.; Kato, Takamitsu A.

    2016-01-01

    Heavy ions, characterized by high linear energy transfer (LET) radiation, have advantages compared with low LET protons and photons in their biological effects. The application of heavy ions within veterinary clinics requires additional background information to determine heavy ion efficacy. In the present study, comparison of the cell-killing effects of photons, protons and heavy ions was investigated in canine osteosarcoma (OSA) cells in vitro. A total of four canine OSA cell lines with various radiosensitivities were irradiated with 137Cs gamma-rays, monoenergetic proton beams, 50 keV/µm carbon ion spread out Bragg peak beams and 200 keV/µm iron ion monoenergetic beams. Clonogenic survival was examined using colony-forming as says, and relative biological effectiveness (RBE) values were calculated relative to gamma-rays using the D10 value, which is determined as the dose (Gy) resulting in 10% survival. For proton irradiation, the RBE values for all four cell lines were 1.0–1.1. For all four cell lines, exposure to carbon ions yielded a decreased cell survival compared with gamma-rays, with the RBE values ranging from 1.56–2.10. Iron ions yielded the lowest cell survival among tested radiation types, with RBE values ranging from 3.51–3.69 observed in the three radioresistant cell lines. The radiosensitive cell line investigated demonstrated similar cell survival for carbon and iron ion irradiation. The results of the present study suggest that heavy ions are more effective for killing radioresistant canine OSA cells when compared with gamma-rays and protons. This markedly increased efficiency of cell killing is an attractive reason for utilizing heavy ions for radioresistant canine OSA. PMID:27446477

  5. Determination of arsenic in ground water using external irradiation of liquid sample by charged particle activation analysis

    International Nuclear Information System (INIS)

    The charged particle activation analysis (CPAA), a sensitive analytical technique for the determination of elemental concentration at trace levels, is ideally suited for solid samples with high melting points. In order to extend the application of CPAA in liquid sample, a programme has been taken to determine total As along with As(III) and As(V) speciation in ground water. A target assembly has been fabricated with Liebig condenser for on-line cooling for external irradiation of water sample with higher beam current to enhance the sensitivity. Arsenic can be determined by producing a suitable activation product 75Se (T1/2 = 119.8 d, Eγ = 136.0, 264.6 keV) by 75As(p,n)75Se reaction. The 18 MeV proton beam is found to be the most suitable as per the published cross section data having maximum cross section ∼ 750 mb at 9 MeV. In this paper, we report the possibility of determination of As by CPAA at trace and ultra trace levels in water sample by calibration with As standard solution in water and standardization work for the separation of As(III) and As(V) from water solutions for speciation study using 74As radiotracers

  6. Heavy charged particle radiotherapy trial

    International Nuclear Information System (INIS)

    Through mid-1985, a total of 49 patients received heavy-charged-particle irradiation for chordoma, chondrosarcoma, meningioma, or neurilemmoma of the base of skull or juxtaspinal area. The mean tumor dose was 68 Gray-equivalent, ranging from 26 to 80. Control within the irradiated area was obtained in 35 of 49. The median follow up in all 49 patients is 21 months, with a range from 3-90 months. Serious complications were seen in a small number of patients, with cranial nerve injury in two, transverse myelitis in one, and brain necrosis in three patients. In 42 patients with tumors of other histologies and/or sites, including tumors of paranasal sinuses, retroperitoneum, soft tissue and miscellaneous other sites, heavy charged particles were also used to deliver a higher tumor dose than possible with standard irradiation techniques. In the group, 21/42 (50%) have had local tumor control, also a good result considering the extent and the range of tumor types treated. The authors believe that there are a number of sites in addition to the juxtaspinal/base of skull tumors that will show long term benefit from treatment with heavy charged particles

  7. Sources for charged particles

    International Nuclear Information System (INIS)

    This document is a basic course on charged particle sources for post-graduate students and thematic schools on large facilities and accelerator physics. A simple but precise description of the creation and the emission of charged particles is presented. This course relies on every year upgraded reference documents. Following relevant topics are considered: electronic emission processes, technological and practical considerations on electron guns, positron sources, production of neutral atoms, ionization, plasma and discharge, different types of positive and negative ion sources, polarized particle sources, materials for the construction of ion sources, low energy beam production and transport. (N.T.)

  8. CFU-S survival and acute radiation lethality in mice irradiated with heavy charged particles (HCP)

    International Nuclear Information System (INIS)

    The authors described previously RBE-LET relationships for CFU-S killing using HCP beams spread to 4 or 10 cm with spiral ridge filters. Studies have been completed with doses in the plateau portion of the Bragg curve where particle fragmentation and the range of dose-averaged LETs are low compared with spread Bragg peaks. Estimates of RBE at 10% survival are 1.5 (/sup 20/Ne), 1.8 (/sup 28/Si), 1.7 (/sup 40/Ar), 1.5 (/sup 40/Ar), and 1.3 (/sup 56/Fe) respectively, compared with /sup 60/Co γ radiation. Based on LET estimates 25, 50, 100, 140, and 190 keV/μm, respectively, for the HCP specified, the authors conclude the RBE peak occurs in the range of 50-100 keV/μm. A similar conclusion was reached from CFU-S survival data collected previously with spread Bragg curves. In conjunction with potential future radiotherapeutic uses of 670 MeV/n /sup 28/Si ions, CFU-S killing was determined in the plateau and in the distal 4 cm of a Bragg curve spread to 12 cm. RBE in the plateau was significantly higher, 1.8, than in the distal peak, 1.2, where LETs estimated at the two positions are 50 and 160 keV/μm, respectively. Data collected on lethality within 30 days after total body exposure is also presented

  9. Heavy charged particle therapy

    International Nuclear Information System (INIS)

    A pilot study of heavy charged particles with heavy ion medical accelerator in Chiba (HIMAC) for advanced H and N cancer has been carried out from June 1994 at National Institute of Radiological Sciences (NIRS). As of the beginning of August 1994, three patients were treated by 290 MeV carbon ions. The patients had adenocarcinoma of the cheek mucosa, squamous cell carcinoma of the ethmoid sinus and adenoid cystic carcinoma of the sublingual gland. Patients were immobilized by individual head coach and thermosplint facial shell. Individual collimators and bolus were also prepared for each ports. Dose fractionation for the initial pilot study group was 16.2 GyE/18 fractions/6 weeks, which would be equivalent to standard fractionation of 60.0 Gy/30 fractions/6 weeks with photons. This dose fractionation was considered to be 20% lesser than 75 GyE/37.5 fractions/7.5 weeks, which is estimated to be maximum tolerance dose for advanced H and N cancers. HIMAC worked well and there was no major trouble causing any treatment delay. Acute skin reactions of 3 patients were 2 cases of bright erythema with patchy moist desquamation and one of dull erythema, which were evaluated as equivalent reaction with irradiated dose. Acute mucosa reactions appeared to have lesser reaction than predicted mucositis. Tumor reactions of three patients were partial reaction (PR) at the end of treatment and nearly complete remission (CR) after 6 months of treatment. From October 1994, we started to treat patients with advanced H and N cancer with 10% high dose than previous dose. And new candidates of pilot study with non small cell lung cancer, brain tumor and carcinoma of the tongue were entered into pilot study. At the end of February 1995, a total of 21 patients were treated by carbon ions. (J.P.N.)

  10. Charged particle beams

    CERN Document Server

    Humphries, Stanley

    2013-01-01

    Detailed enough for a text and sufficiently comprehensive for a reference, this volume addresses topics vital to understanding high-power accelerators and high-brightness-charged particle beams. Subjects include stochastic cooling, high-brightness injectors, and the free electron laser. Humphries provides students with the critical skills necessary for the problem-solving insights unique to collective physics problems. 1990 edition.

  11. Charged Particle Optics Theory

    Czech Academy of Sciences Publication Activity Database

    Hawkes, P. W.; Lencová, Bohumila

    -, č. 6 (2006), s. 6-8 Grant ostatní: EC 5RP(XE) G5RD-CT-2000-00344 Institutional research plan: CEZ:AV0Z20650511 Keywords : optics of charged particles * design of ion lithography system * spot profile * the finite element method Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering www.phantomsnet.net

  12. Measurement of charged particle yields from PMMA irradiated by a 220 MeV/u12Cbeam

    CERN Document Server

    Piersanti, L; Bini, FU. Rome La Sapienza (main); Collamati, F; De Lucia, E; Durante, M; Faccini, R; Ferroni, F; Fiore, S; Iarocci, E; La Tessa, C; Marafini, M; Mattei, I; Patera, V; Ortega, P G; Sarti, A; Schuy, C; Sciubba, A; Vanstalle, M; Voena, C

    2014-01-01

    The radiation used in hadrontherapy treatments interacts with the patient body producing secondary particles, either neutral or charged, that can be used for dose and Bragg peak monitoring and to provide a fast feedback on the treatment plans. Recent results obtained from the authors on simplified setups (mono-energetic primary beams interacting with homogeneous tissue like target) have already indicated the correlation that exists between the flux of these secondaries coming from the target (e.g. protons and photons) and the position of the primary beam Bragg peak. In this paper, the measurements of charged particle fluxes produced by the interaction of a 220 MeV/u carbon ion beam at GSI, Darmstadt, with a polymethyl methacrylate target are reported. The emission region of protons (p), deuterons (d) and tritons (t) has been characterized using a drift chamber while the particle time-of-flight, used to compute the kinetic energy spectra, was measured with a LYSO scintillator.The energy released in the LYSO cr...

  13. Co-culturing with High-Charge and Energy Particle Irradiated Cells Increases Mutagenic Joining of Enzymatically Induced DNA Double-Strand Breaks in Nonirradiated Cells.

    Science.gov (United States)

    Li, Zhentian; Doho, Gregory; Zheng, Xuan; Jella, Kishore Kumar; Li, Shuyi; Wang, Ya; Dynan, William S

    2015-09-01

    Cell populations that have been exposed to high-charge and energy (HZE) particle radiation, and then challenged by expression of a rare-cutting nuclease, show an increased frequency of deletions and translocations originating at the enzyme cut sites. Here, we examine whether this effect also occurs in nonirradiated cells that have been co-cultured with irradiated cells. Human cells were irradiated with 0.3-1.0 Gy of either 600 MeV/u (56)Fe or 1,000 MeV/u (48)Ti ions or with 0.3-3.0 Gy of 320 kV X rays. These were co-cultured with I-SceI-expressing reporter cells at intervals up to 21 days postirradiation. Co-culture with HZE-irradiated cells led to an increase in the frequency of I-SceI-stimulated translocations and deletions in the nonirradiated cells. The effect size was similar to that seen previously in directly irradiated populations (maximum effect in bystander cells of 1.7- to 4-fold depending on ion and end point). The effect was not observed when X-ray-irradiated cells were co-cultured with nonirradiated cells, but was correlated with an increase in γ-H2AX foci-positive cells in the nonirradiated population, suggesting the presence of genomic stress. Transcriptional profiling of a directly irradiated cell population showed that many genes for cytokines and other secretory proteins were persistently upregulated, but their induction was not well correlated with functional effects on repair in co-cultured cells, suggesting that this transcriptional response alone is not sufficient to evoke the effect. The finding that HZE-irradiated cells influence the DNA double-strand break repair fidelity in their nonirradiated neighbors has implications for risk in the space radiation environment. PMID:26284422

  14. Nanodosimetry of charged particles

    International Nuclear Information System (INIS)

    In last year's annual report, the authors described the development of an ultra-miniature counter (UMC), described some of its physical characteristics, and presented some first measurements with this counter of microdosimetric spectra for neutrons (15 MeV) and photons (137Cs). It remains to investigate in more detail the operational characteristics of the UMC and if possible, to make a comparison of relevant physical parameters such as gain and multiplication radius with the Segur theory. In order to accomplish these objectives, it is necessary to build a wall-less version of the UMC, which will be amenable to calibration and investigation with collimated beams of charged particles. The design of such a counter has been worked out in principle. Investigations into the optimal design of electrode structures and dimensions are being carried out at present. The main problem occurs with the design of the grid structure which is required to define the outer boundary of the collecting volume. Our initial attempts would make it appear at present that a counter of 1 to 1.5 mm diameter is feasible. This should be more than adequate to provide an appropriately wall-less counter within a reasonable size cavity. It will probably be about a year before a working counter can be produced. In the interim, it is possible to make some initial efforts into the investigation of operational characteristics of a wall-less UMC by making use of similar design, but at a somewhat larger size. These first attempts at measurement of charged particle microdosimetric spectra at nanometer site provide added evidence that these counters can yield useful microdosimetric data at far smaller site sizes than heretofore attempted. They also provide added incentive and encouragement for development of wall-less UMC

  15. Treatment of cancer with heavy charged particles

    International Nuclear Information System (INIS)

    The goals of the clinical helium and heavy charged particle radiotherapy trial are: (1) to evaluate the potential of improved dose localization as exemplified by helium-ion irradiation where little, if any, biological advantage is expected; and (2) to evaluate the combined potential of improved dose localization and increased biological effect available with heavier ions such as carbon, neon, silicon, and argon ions

  16. Radiation-thermal effects change of physico-mechanical properties in reactor materials irradiated with neutrons and energetic charged particles

    International Nuclear Information System (INIS)

    In the first part of the report (chapter 1) the earlier results of the important scientific and technological investigations which were performed in the seventies years in Poland have been presented. They concerned the fabrication, corrosion, mechanical properties of materials for research and power reactors. Being of the general survey character, the chapter includes own, original results of research of thermal irradiation effects on microstructure evolution phase transformations and mechanical properties of reactor materials. The kinetics of isothermal transformation β→α in U-Cr 0.4% wt. alloy has been studied. Factors affecting stress-corrosion cracking of zirconium in iodine vapour have been investigated. The rings and loops for irradiation specimens and Hot Laboratory for postirradiation examination of construction materials is described. In the second part (chapters 2, 3, 4, 5) performed the investigations and simulations of radiation damage in metals by heavy ion beams (E > 1 MeV/a.m.n.) were described scientific base and technical problems of the method of irradiation of heavy ions and of the examination of irradiated samples is presented. It is followed by a summary of the results of simulation and reactor experiments on different materials. Radiation hardening of a number metals (Al, Zr, Cu, Ni, U) irradiated by heavy ion and neutrons, mechanical properties and microstructural evolution in ion and neutron irradiated austenitic stainless steel is described. The last chapter is a description of practical aspects of the presented studies in nuclear science and technology. (author)

  17. Intercellular communication amplifies stressful effects in high-charge, high-energy (HZE) particle-irradiated human cells

    International Nuclear Information System (INIS)

    Understanding the mechanisms that underlay the biological effects of particulate radiations is essential for space exploration and for radiotherapy. Here, we investigated the role of gap junction intercellular communication (GJIC) in modulating harmful effects induced in confluent cultures wherein most cells are traversed by one or more radiation tracks. We focused on the effect of radiation quality (linear energy transfer; LET) on junctional propagation of DNA damage and cell death among the irradiated cells. Confluent normal human fibroblasts were exposed to graded doses of 1 GeV protons (LET ∼0.2 keV/μm) or 1 GeV/u iron ions (LET ∼151 keV/μm) and were assayed for clonogenic survival and for micronucleus formation, a reflection of DNA damage, shortly after irradiation and following longer incubation periods. Iron ions were ∼2.7 fold more effective than protons at killing 90% of the cells in the exposed cultures when assayed within 5-10 minutes after irradiation. When cells were held in the confluent state for several hours after irradiation, substantial potentially lethal damage repair (PLDR), coupled with a reduction in micronucleus formation, occurred in cells exposed to protons, but not in those exposed to iron ions. In fact, such confluent holding after exposure to a similarly toxic dose of iron ions enhanced the induced toxic effect. However, following iron ion irradiation, inhibition of GJIC by 18-α-glycyrrhetinic acid eliminated the enhanced toxicity and reduced micronucleus formation to levels below those detected in cells assayed shortly after irradiation. The data show that low-LET radiation induces strong PLDR within hours, but that high-LET radiation with similar immediate toxicity does not induce PLDR and its toxicity increases with time following irradiation. The results also show that GJIC among irradiated cells amplifies stressful effects following exposure to high-, but not low-LET radiation, and that GJIC has only minimal effect on

  18. Optics of charged particles

    International Nuclear Information System (INIS)

    Suitable for both the specialist and non-specialist, this book develops all statements from first principles. Key chapters of the book focus upon how to design particle-optical systems, the systematics of image abberations, the effects of fringing fields, systematics of beams, and solutions for particle-optical systems. An undergraduate background in physics and mathematics is required for this work

  19. Differential Superiority of Heavy Charged-Particle Irradiation to X-Rays: Studies on Biological Effectiveness and Side Effect Mechanisms in Multicellular Tumor and Normal Tissue Models.

    Science.gov (United States)

    Walenta, Stefan; Mueller-Klieser, Wolfgang

    2016-01-01

    This review is focused on the radiobiology of carbon ions compared to X-rays using multicellular models of tumors and normal mucosa. The first part summarizes basic radiobiological effects, as observed in cancer cells. The second, more clinically oriented part of the review, deals with radiation-induced cell migration and mucositis. Multicellular spheroids from V79 hamster cells were irradiated with X-rays or carbon ions under ambient or restricted oxygen supply conditions. Reliable oxygen enhancement ratios could be derived to be 2.9, 2.8, and 1.4 for irradiation with photons, (12)C(+6) in the plateau region, and (12)C(+6) in the Bragg peak, respectively. Similarly, a relative biological effectiveness of 4.3 and 2.1 for ambient pO2 and hypoxia was obtained, respectively. The high effectiveness of carbon ions was reflected by an enhanced accumulation of cells in G2/M and a dose-dependent massive induction of apoptosis. These data clearly show that heavy charged particles are more efficient in sterilizing tumor cells than conventional irradiation even under hypoxic conditions. Clinically relevant doses (3 Gy) of X-rays induced an increase in migratory activity of U87 but not of LN229 or HCT116 tumor cells. Such an increase in cell motility following irradiation in situ could be the source of recurrence. In contrast, carbon ion treatment was associated with a dose-dependent decrease in migration with all cell lines and under all conditions investigated. The radiation-induced loss of cell motility was correlated, in most cases, with corresponding changes in β1 integrin expression. The photon-induced increase in cell migration was paralleled by an elevated phosphorylation status of the epidermal growth factor receptor and AKT-ERK1/2 pathway. Such a hyperphosphorylation did not occur during (12)C(+6) irradiation under all conditions registered. Comparing the gene toxicity of X-rays with that of particles using the γH2AX technique in organotypic cultures of the oral

  20. Differential Superiority of Heavy Charged-Particle Irradiation to X-Rays: Studies on Biological Effectiveness and Side Effect Mechanisms in Multicellular Tumor and Normal Tissue Models

    Science.gov (United States)

    Walenta, Stefan; Mueller-Klieser, Wolfgang

    2016-01-01

    This review is focused on the radiobiology of carbon ions compared to X-rays using multicellular models of tumors and normal mucosa. The first part summarizes basic radiobiological effects, as observed in cancer cells. The second, more clinically oriented part of the review, deals with radiation-induced cell migration and mucositis. Multicellular spheroids from V79 hamster cells were irradiated with X-rays or carbon ions under ambient or restricted oxygen supply conditions. Reliable oxygen enhancement ratios could be derived to be 2.9, 2.8, and 1.4 for irradiation with photons, 12C+6 in the plateau region, and 12C+6 in the Bragg peak, respectively. Similarly, a relative biological effectiveness of 4.3 and 2.1 for ambient pO2 and hypoxia was obtained, respectively. The high effectiveness of carbon ions was reflected by an enhanced accumulation of cells in G2/M and a dose-dependent massive induction of apoptosis. These data clearly show that heavy charged particles are more efficient in sterilizing tumor cells than conventional irradiation even under hypoxic conditions. Clinically relevant doses (3 Gy) of X-rays induced an increase in migratory activity of U87 but not of LN229 or HCT116 tumor cells. Such an increase in cell motility following irradiation in situ could be the source of recurrence. In contrast, carbon ion treatment was associated with a dose-dependent decrease in migration with all cell lines and under all conditions investigated. The radiation-induced loss of cell motility was correlated, in most cases, with corresponding changes in β1 integrin expression. The photon-induced increase in cell migration was paralleled by an elevated phosphorylation status of the epidermal growth factor receptor and AKT-ERK1/2 pathway. Such a hyperphosphorylation did not occur during 12C+6 irradiation under all conditions registered. Comparing the gene toxicity of X-rays with that of particles using the γH2AX technique in organotypic cultures of the oral mucosa, the

  1. Measuring momentum for charged particle tomography

    Science.gov (United States)

    Morris, Christopher; Fraser, Andrew Mcleod; Schultz, Larry Joe; Borozdin, Konstantin N.; Klimenko, Alexei Vasilievich; Sossong, Michael James; Blanpied, Gary

    2010-11-23

    Methods, apparatus and systems for detecting charged particles and obtaining tomography of a volume by measuring charged particles including measuring the momentum of a charged particle passing through a charged particle detector. Sets of position sensitive detectors measure scattering of the charged particle. The position sensitive detectors having sufficient mass to cause the charged particle passing through the position sensitive detectors to scatter in the position sensitive detectors. A controller can be adapted and arranged to receive scattering measurements of the charged particle from the charged particle detector, determine at least one trajectory of the charged particle from the measured scattering; and determine at least one momentum measurement of the charged particle from the at least one trajectory. The charged particle can be a cosmic ray-produced charged particle, such as a cosmic ray-produced muon. The position sensitive detectors can be drift cells, such as gas-filled drift tubes.

  2. Microstructural developments in Fe-Cr-W low activation ferritic steels under dual beam charged particle irradiation

    International Nuclear Information System (INIS)

    Chromium-molybdenum ferritic steels have a better resistance to void swelling than austenitic steels and were considered for use as first wall structural materials in future fusion reactors. One of the major alloying elements, Mo, is deleterious for the reduction of radioactivity; reduced activation steels are under development, where Mo is replaced by W. In this work, four kinds of reduced activation steels were dual or single ion irradiated to 125 dpa. In the duel ion irradiated steels with a 7-12% Cr content, the dimensional stability of the martensite phase was superior to the other phases. The cavity microstructures of bainitic steels with 2.25% Cr content were affected by the He/dpa ratio (and by the He injection rate) even when they had a high damage level (up to 125 dpa.) Hitherto, the low activation steels developed by replacing Mo by W suggest excellent stability of microstructures and thus a high resistance to swelling. (orig.)

  3. Dust particle charging in sheath

    International Nuclear Information System (INIS)

    The charging and the screening of spherical dust particles in sheaths near the wall were studied using computer simulation. The three-dimensional PIC/MCC method and molecular dynamics method were applied to describe plasma particles motion and interaction with macroscopic dust grain. Calculations were carried out at different neutral gas pressures and wall potentials. Values of the charge of the dust particles and spatial distributions of plasma parameters are obtained by modelling. The results have shown that the charge of the dust particles in the sheath, as well as the spatial distribution of the ions and electrons near the dust particles, depend strongly on the wall potential. It is shown that for large negative values of the wall potential the negative charge of a dust particle decreases due to the decline of the electron density in its vicinity. In addition, the flow of energy of the ions on the surface of dust particles is increased due to better focusing effect of the dust particle field on ions.

  4. Tumor therapy with heavy charged particles

    Science.gov (United States)

    Blattmann, Hans

    1999-11-01

    Nuclear science has contributed significantly to the development of tumor therapy with heavy charged particles. Interest evolved for neutron therapies in the forties because of the increased radiobiological effectiveness (RBE) compared to photon irradiation. The development of more powerful proton and heavy ion accelerators with higher energies or higher intensities, made new particles for radiation therapy available. Pions, protons, light ions, from helium up to silicon were studied in view of precision dose delivery and increased RBE. Without the parallel development of new diagnostic techniques such as computer tomography (CT) and positron emission tomography (PET) the rapid development would not have been possible. Heavy-charged particle therapy has now come into a consolidation phase. Hospital-based facilities are built by industry, and research institutes focus on refinements in dose delivery and treatment planning, as well as systems for monitoring dose delivery and for dose distribution verification.

  5. High-frequency charged particle accelerator

    International Nuclear Information System (INIS)

    The device is refered to technical physics and may be used as a source of accelerated particles for irradiation of different objects in industry and agriculture. The device is aimed at increase of the power and enhancement of stability of the accelerator operation and decrease of its dimensions. High-frequency accelerator is composed of an accelerating cavity resonator a charged particle source and HF power supply. The aim is attained by the fact, that HF power source anode is made as one of coupling capasitor plates, the second plate of which is the nearest to anode HF power supply grid. The coupling capacitor plalte functional union with the HF power supply electrodes (anode and grid) reduces to spirious inductances of HF power supply circuit to minimum. Besides, the accelerator structure is simplified, as additional cooling system for the charged particle source is not necessary

  6. Charged-particle coating

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, W.L.; Crane, J.K.; Hendricks, C.D.

    1980-08-29

    Advanced target designs require thicker (approx. 300 ..mu..m) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized.

  7. Charged-particle coating

    International Nuclear Information System (INIS)

    Advanced target designs require thicker (approx. 300 μm) coatings and better surface finishes that can be produced with current coating techniques. An advanced coating technique is proposed to provide maximum control of the coating flux and optimum manipulation of the shell during processing. In this scheme a small beam of ions or particles of known incident energy are collided with a levitated spherical mandrel. Precise control of the incident energy and angle of the deposition flux optimizes the control of the coating morphology while controlled rotation and noncontact support of the shell minimizes the possibility of particulate or damage generated defects. Almost infinite variability of the incident energy and material in this process provides increased flexibility of the target designs which can be physically realized

  8. Charged particle acceleration with plasmas

    International Nuclear Information System (INIS)

    Under certain conditions it is possible to create spatial charge waves (OCE) in a plasma (ionized gas) through some disturbance mechanism, the phenomenon produces electric fields of high intensity that are propagated at velocities near to a c. When charged particles are connected to such OCE they may be accelerated to very high energies in short distances. At present electric fields of approximately 107 V/cm have been observed. (Author). 4 refs

  9. The isotopic analysis of boron by charged particle irradiation; Analise isotopica de boro utilizando feixes de particulas carregadas

    Energy Technology Data Exchange (ETDEWEB)

    Vinagre Junior, Ubirajara M.; Costa, Vilmar L. da; Suita, Julio C.; Teixeira, Danilo L.; Bernedo, Alfredo V.B.; Cabral, Tania S. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)

    1997-12-01

    An analytical isotopic method for boron analysis is discribed, based in the spectrometry of protons at 130{sup 0} C from scattering and/or reactions like {sup 10} B(p,p){sup 10} B and {sup 11} B(p,p){sup 11} B which were simultaneously measured. The basic parameters involved in such measurements, are discussed including cinematic, angular distribution, preparation of targets and its substracs. Particle spectra of targets with natural isotopic concentration and enriched in {sup 10} B are presented. The ratio [{sup 11} B(p{sub o})/{sup 10} B(p{sub o})] at 130{sup 0} C for targets of {sup nat} B in respect of the incident proton beam energy between 14 and 24 MeV are shown. The results of our enriched {sup 10} B are compared with results obtained in mass spectrometry. (author). 14 refs., 6 figs., 1 tab.

  10. CVD diamond sensors for charged particle detection

    CERN Document Server

    Krammer, Manfred; Berdermann, E; Bergonzo, P; Bertuccio, G; Bogani, F; Borchi, E; Brambilla, A; Bruzzi, Mara; Colledani, C; Conway, J; D'Angelo, P; Dabrowski, W; Delpierre, P A; Dencuville, A; Dulinski, W; van Eijk, B; Fallou, A; Fizzotti, F; Foulon, F; Friedl, M; Gan, K K; Gheeraert, E; Hallewell, G D; Han, S; Hartjes, F G; Hrubec, Josef; Husson, D; Kagan, H; Kania, D R; Kaplon, J; Kass, R; Koeth, T W; Lo Giudice, A; Lü, R; MacLynne, L; Manfredotti, C; Meier, D; Mishina, M; Moroni, L; Oh, A; Pan, L S; Pernicka, Manfred; Peitz, A; Perera, L P; Pirollo, S; Procario, M; Riester, J L; Roe, S; Rousseau, L; Rudge, A; Russ, J; Sala, S; Sampietro, M; Schnetzer, S; Sciortino, S; Stelzer, H; Stone, R; Suter, B; Tapper, R J; Tesarek, R; Trischuk, W; Tromson, D; Vittone, E; Walsh, A M; Wedenig, R; Weilhammer, Peter; Wetstein, M; White, C; Zeuner, W; Zöller, M

    2001-01-01

    CVD diamond material was used to build position-sensitive detectors for single-charged particles to be employed in high-intensity physics experiments. To obtain position information, metal contacts shaped as strips or pixels are applied to the detector surface for one- or two- dimensional coordinate measurement. Strip detectors 2*4 cm/sup 2/ in size with a strip distance of 50 mu m were tested. Pixel detectors of various pixel sizes were bump bonded to electronics chips and investigated. A key issue for the use of these sensors in high intensity experiments is the radiation hardness. Several irradiation experiments were carried out with pions, protons and neutrons exceeding a fluence of 10/sup 15/ particles/cm/sup 2/. The paper presents an overview of the results obtained with strip and pixel detectors in high-energy test beams and summarises the irradiation studies. (8 refs).

  11. High-LET charged particle radiotherapy

    International Nuclear Information System (INIS)

    The Department of Radiation Oncology at UCSF Medical Center and the Radiation Oncology Department at UC Lawrence Berkeley Laboratory have been evaluating the use of high LET charged particle radiotherapy in a Phase 1--2 research trial ongoing since 1979. In this clinical trail, 239 patients have received at least 10 Gy (physical) minimum tumor dose with neon ions, meaning that at least one-half of their total treatment was given with high-LET charged particle therapy. Ninety-one patients received all of their therapy with neon ions. Of the 239 patients irradiated, target sites included lesions in the skin, subcutaneous tissues, head and neck such as paranasal sinuses, nasopharynx and salivary glands (major and minor), skull base and juxtaspinal area, GI tract including esophagus, pancreas and biliary tract, prostate, lung, soft tissue and bone. Analysis of these patients has been carried out with a minimum followup period of 2 years

  12. Magnetic guidance of charged particles

    CERN Document Server

    Dubbers, Dirk

    2015-01-01

    Many experiments and devices in physics use static magnetic fields to guide charged particles from a source onto a detector, and we ask the innocent question: What is the distribution of particle intensity over the detector surface? One should think that the solution to this seemingly simple problem is well known. We show that, even for uniform guide fields, this is not the case and present analytical point spread functions (PSF) for magnetic transport that deviate strongly from previous results. The "magnetic" PSF shows unexpected singularities, which were recently also observed experimentally, and which make detector response very sensitive to minute changes of position, field amplitude, or particle energy. In the field of low-energy particle physics, these singularities may become a source of error in modern high precision experiments, or may be used for instrument tests, for instance in neutrino mass retardation spectrometers.

  13. Magnetic guidance of charged particles

    Directory of Open Access Journals (Sweden)

    Dirk Dubbers

    2015-09-01

    Full Text Available Many experiments and devices in physics use static magnetic fields to guide charged particles from a source onto a detector, and we ask the innocent question: What is the distribution of particle intensity over the detector surface? One should think that the solution to this seemingly simple problem is well known. We show that, even for uniform guide fields, this is not the case, and we present analytical point spread functions (PSF for magnetic transport that deviate strongly from previous results. The “magnetic” PSF shows unexpected singularities, which were recently also observed experimentally, and which make detector response very sensitive to minute changes of position, field amplitude, or particle energy. In the field of low-energy particle physics, these singularities may become a source of error in modern high precision experiments, or may be used for instrument tests.

  14. Geometrical charged-particle optics

    CERN Document Server

    Rose, Harald

    2012-01-01

    This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are...

  15. Medium energy charged particle spectrometer

    International Nuclear Information System (INIS)

    The charged particle spectrometer E8 on HELIOS A and B will be described in some detail. It covers proton energies from 80 keV to 6 MeV, electrons from 20 keV to 2 MeV, and positrons from 150 to 550 keV. Its flight performance will be discussed. From examples of measurements the capability of the instrument will be demonstrated. (orig.)

  16. Computations in Charged Particle Optics

    Czech Academy of Sciences Publication Activity Database

    Oral, Martin; Radlička, Tomáš

    Brno: Institute of Scientific Instruments AS CR, v. v. i, 2014, s. 23-24. ISBN 978-80-87441-12-1. [Workshop of Interesting Topics of SEM and ESEM. Mikulov (CZ), 26.08.2014-31.08.2014] R&D Projects: GA MŠk EE.2.3.20.0103 Institutional support: RVO:68081731 Keywords : charged Particle Optics * computations Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  17. Heavy charged particle dosimetry, theory and application

    International Nuclear Information System (INIS)

    Experiments were made to verify the theory of the transport of heavy particles through a medium using L-α-alaline for the detection of radiation. The dose response of L-α-alaline was measured for X-ray radiation of an energy of 4 to 16 MeV, electron radiation of an energy of 6, 10 and 20 MeV, low-LET radiation, 16 MeV and 6 MeV protons, 20 MeV particles and other charged particles. Of the measured dose responses RE values were experimentally obtained and compared with calculated results. Free and very stable radicals were obtained by radiation. Fading of low-LET and high-LET radiation was determined as induced by the said radicals. Using ESR spectra it was found that diverse chemical reactions take place in the track of high-LET particles. However, chemical reactions in the track of a heavy charged particle will be the same if the medium is homogeneously irradiated with low-LET radiation. (E.S.). 7 figs., 1 tab., 11 refs

  18. Direct charged particle imaging sensors

    International Nuclear Information System (INIS)

    CMOS image sensors optimized for charged particle imaging applications, such as electron microscopy and particle physics, have been designed and characterized. These directly image charged particles without reliance on performance-degrading hybrid technologies such as the use of scintillating materials. Based on standard CMOS active pixel sensor (APS) technology, the sensor arrays uses an 8-20 μm epitaxial layer that acts as a thicker sensitive region for the generation and collection of ionization electrons resulting from impinging high-energy particles. This results in a 100% fill factor and a far larger signal per incident electron than a standard CMOS photodiode could provide. A 512x550 pixels prototype has been fabricated and used extensively in an electron microscope, including having been used to take sample images. Temporal noise was measured to be 0.9 mV RMS, and the dynamic range was 60 dB. Power consumption at 70 frames/s is 20 mW. The full-width half-maximum of the collected ionization electron distribution was found to be 5.5 μm, yielding a spatial resolution of approximately 2.3 μm for individual incident electrons, and the modulation transfer function of the sensor at the Nyquist limit is to be 32%

  19. The dynamics of a charged particle

    OpenAIRE

    Rohrlich, Fritz

    2008-01-01

    Using physical arguments, I derive the physically correct equations of motion for a classical charged particle from the Lorentz-Abraham-Dirac equations (LAD) which are well known to be physically incorrect. Since a charged particle can classically not be a point particle because of the Coulomb field divergence, my derivation accounts for that by imposing a basic condition on the external force. That condition ensures that the particle's finite size charge distribution looks like a point charg...

  20. Interactions of charged dust particles in clouds of charges

    Science.gov (United States)

    Gundienkov, Vladimir; Yakovlenko, Sergey

    2004-03-01

    Two charged dust particles inside a cloud of charges are considered as Debye atoms forming a Debye molecule. Cassini coordinates are used for the numerical solution of the Poisson-Boltzmann equation for the charged cloud. The electric force acting on a dust particle by the other dust particle was determined by integrating the electrostatic pressure on the surface of the dust particle. It is shown that attractive forces appear when the following two conditions are satisfied. First, the average distance between dust particles should be approximately equal to two Debye radii. Second, attraction takes place when similar charges are concentrated predominantly on the dust particles. If the particles carry a small fraction of total charge of the same polarity, repulsion between the particles takes place at all distances. We apply our results to the experiments with thermoemission plasma and to the experiments with nuclear-pumped plasma.

  1. Supplementary kinetic constants of charged particles

    OpenAIRE

    Ribaric, Marijan; Sustersic, Luka

    2006-01-01

    We put forward: (A) An improved description of classical, kinetic properties of a charged pointlike physical particle that consists, in addition to its mass and charge, also of the Eliezer and Bhabha kinetic constants; and (B) a proposal to evaluate these kinetic constants by considering the trajectories of charged particles in an acccelerator.

  2. Charge collection efficiency simulations of irradiated silicon strip detectors

    International Nuclear Information System (INIS)

    During the scheduled high luminosity upgrade of LHC, the world's largest particle physics accelerator at CERN, the position sensitive silicon detectors installed in the vertex and tracking part of the CMS experiment will face a more intense radiation environment than the present system was designed for. Thus, to upgrade the tracker to the required performance level, comprehensive measurements and simulation studies have already been carried out. Essential information of the performance of an irradiated silicon detector is obtained by monitoring its charge collection efficiency (CCE). From the evolution of CCE with fluence, it is possible to directly observe the effect of the radiation induced defects on the ability of the detector to collect charge carriers generated by traversing minimum ionizing particles (MIPs). In this paper the numerically simulated CCE and CCE loss between the strips of irradiated silicon strip detectors are presented. The simulations based on the Synopsys Sentaurus TCAD framework were performed before and after irradiation for fluences up to 1.5 × 1015 neqcm−2 for n-on-p sensors. A two level defect model and non-uniform three level defect model were applied for the proton irradiation simulations, and a two level model for neutrons. The results are presented together with the measurements of strip detectors irradiated by different particles and fluences and show considerable agreement for both CCE and its position dependency

  3. Differential superiority of heavy charged-particle irradiation to x-rays: Studies on biological effectivenes and side effect mechanisms in multicellular tumor and normal tissue models

    Directory of Open Access Journals (Sweden)

    Stefan eWalenta

    2016-02-01

    Full Text Available This review is focused on the radiobiology of carbon ions compared to x-rays using multicellular models of tumors and normal mucosa. The first part summarizes basic radiobiological effects, as observed in cancer cells. The second, more clinically oriented part of the review deals with radiation-induced cell migration and mucositis.Multicellular spheroids (MCS from V79 hamster cells were irradiated with x-rays or carbon ions under ambient or restricted oxygen supply conditions. Oxygen enhancement ratios (OER were 2.9, 2.8, and 1.4 for irradiation with photons, 12C+6 in the plateau region, and 12C+6 in the Bragg peak, respectively. A relative biological effectiveness (RBE of 4.3 and 2.1 for ambient pO2 and hypoxia was obtained, respectively. The high effectiveness of carbon ions was reflected by an enhanced accumulation of cells in G2/M, and a dose-dependent massive induction of apoptosis. Clinically relevant doses (3 Gy of x-rays induced an increase in migratory activity of U87 but not of LN229 or HCT116 tumor cells. Such an increase in cell motility following irradiation in situ could be the source of recurrence. In contrast, carbon ion treatment was associated with a dose-dependent decrease in migration with all cell lines and under all conditions investigated. The radiation-induced loss of cell motility was correlated, in most cases, with corresponding changes in 1 integrin expression. Unlike with particles, the photon-induced increase in cell migration was paralleled by an elevated phosphorylation status of the epidermal growth factor receptor (EGFR and AKT-ERK1/2 pathway. Comparing the gene toxicity of x-rays with that of particles using the gamma-H2AX technique in organotypic cultures of the oral mucosa, the superior effectiveness of heavy ions was confirmed by a two-fold higher number of foci per nucleus. Pro-inflammatory signs, however, were similar for both treatment modalities, e. g., the activation of NFkappaB, and the release of IL

  4. Spinning charged test particles and Cosmic Censorship

    International Nuclear Information System (INIS)

    The authors consider spinning charged test particles in the gravitational field of a rotating charged black hole, and it is shown that the hole cannot be destroyed, according to the Cosmic Censorship hypothesis. (Auth.)

  5. CMOS sensor as charged particles and ionizing radiation detector

    International Nuclear Information System (INIS)

    This paper reports results of CMOS sensor suitable for use as charged particles and ionizing radiation detector. The CMOS sensor with 640 × 480 pixels area has been integrated into an electronic circuit for detection of ionizing radiation and it was exposed to alpha particle (Am-241, Unat), beta (Sr-90), and gamma photons (Cs-137). Results show after long period of time (168 h) irradiation the sensor had not loss of functionality and also the energy of the charge particles and photons were very well obtained

  6. Charge of dust particles in a particle chain

    CERN Document Server

    Yousefi, Razieh; Matthews, Lorin Swint; Hyde, Truell W

    2016-01-01

    Charged dust particles form structures which are extended in the vertical direction in the electrode sheath of a rf discharge when confined within a glass box. The charge on each particle as a function of height varies due to the changing plasma conditions and the wakefield of upstream particles. Here an analysis of the equilibrium state of chains of varying number of particles is analyzed to determine the charge on each particle within a vertically extended chain as well as the magnitude of the positive wakefield charge.

  7. Charge Collection Efficiency Simulations of Irradiated Silicon Strip Detectors

    CERN Document Server

    Peltola, T

    2014-01-01

    During the scheduled high luminosity upgrade of LHC, the world's largest particle physics accelerator at CERN, the position sensitive silicon detectors installed in the vertex and tracking part of the CMS experiment will face more intense radiation environment than the present system was designed for. Thus, to upgrade the tracker to required performance level, comprehensive measurements and simulations studies have already been carried out. Essential information of the performance of an irradiated silicon detector is obtained by monitoring its charge collection efficiency (CCE). From the evolution of CCE with fluence, it is possible to directly observe the effect of the radiation induced defects to the ability of the detector to collect charge carriers generated by traversing minimum ionizing particles (mip). In this paper the numerically simulated CCE and CCE loss between the strips of irradiated silicon strip detectors are presented. The simulations based on Synopsys Sentaurus TCAD framework were performed ...

  8. Study of the liquid water luminescence induced by charged particles

    International Nuclear Information System (INIS)

    Many observations suggested that liquid water (with impurities) could give a luminescence output when irradiated with charged particles. We investigate theoretical and practical possibility of detecting such luminescence. Preliminary results on this possibility are presented, and a layout of the device proposed for measuring luminescence is given. (authors)

  9. Worldline deviations of charged spinning particles

    Energy Technology Data Exchange (ETDEWEB)

    Heydari-Fard, M. [Department of Physics, Shahid Beheshti University, Evin, 19839 Tehran (Iran, Islamic Republic of); Mohseni, M. [Physics Department, Payame Noor University, 19395-4697 Tehran (Iran, Islamic Republic of)]. E-mail: m-mohseni@pnu.ac.ir; Sepangi, H.R. [Department of Physics, Shahid Beheshti University, Evin, 19839 Tehran (Iran, Islamic Republic of); Institute for Studies in Theoretical Physics and Mathematics, Tehran (Iran, Islamic Republic of)

    2005-10-20

    The geodesic deviation equation is generalized to worldline deviation equations describing the relative accelerations of charged spinning particles in the framework of Dixon-Souriau equations of motion.

  10. Worldline deviations of charged spinning particles

    CERN Document Server

    Heydari-Fard, M; Sepangi, H R

    2005-01-01

    The geodesic deviation equation is generalized to worldline deviation equations describing the relative accelerations of charged spinning particles in the framework of Dixon-Souriau equations of motion.

  11. Delay Equation for Charged Brown Particle

    OpenAIRE

    Vlasov, Alexander A.

    2001-01-01

    In previous work (physics/0004026) was shown, with the help of numerical calculations, that the effective Brown temperature for charged particle is lower than that for particle without charge. Here we derive this result without numerical calculations, integrating the delay equation analytically, as for zero, so for nonzero viscosity.

  12. Scintillation Detectors for Charged Particles and Photons

    CERN Document Server

    Lecoq, P

    2011-01-01

    Scintillation Detectors for Charged Particles and Photons in 'Charged Particle Detectors - Particle Detectors and Detector Systems', part of 'Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms: Numerical Data and Functional Relationships in Science and Technology, Volume 21B1: Detectors for Particles and Radiation. Part 1: Principles and Methods'. This document is part of Part 1 'Principles and Methods' of Subvolume B 'Detectors for Particles and Radiation' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Subsection '3.1.1 Scintillation Detectors for Charged Particles and Photons' of Section '3.1 Charged Particle Detectors' of Chapter '3 Particle Detectors and Detector Systems' with the content: 3.1.1 Scintillation Detectors for Charged Particles and Photons 3.1.1.1 Basic detector principles and scintillator requirements 3.1.1.1.1 Interaction of ionizing radiation with scintillator material 3.1.1.1.2 Important scint...

  13. Charged-particle activation analysis

    International Nuclear Information System (INIS)

    The paper discusses the methodology and application of nuclear activation with ion beams (19 via 16O(3He,p)18F, 12C(3He,α)11C and 14N(p,α)11C respectively. Recently, triton activation has been shown to be inherently still superior to 3He activation for the determination of oxygen [16O(3H,n)18F]. Lithium, boron, carbon and sulphur can be detected rapidly, nondestructively and with high sensitivity (approximately 0.25ppm for Li and B) via ''quasi-prompt'' activation based on the detection of short-lived, high-energy beta emitters (10ms1H(7Li,n)7Be for example. Nondestructive multielement analysis: Proton activation has the inherent potential for meeting requirements of broad elemental coverage, sensitivity (ppm and sub-ppm range) and selectivity. Up to 30 elements have been determined in Al, Co, Ag, Nb, Rh, Ta and biological samples, using 12-MeV proton activation followed by gamma-ray spectrometry. These capabilities are further enhanced with the counting of X-ray emitters, 28 elements (269) and accuracy using proton activation. 204Pb/206Pb ratios can also be determined with a relative precision of a few per cent. Although charged-particle activation analysis is a well-established trace analysis technique, broad potential capabilities remain to be explored, e.g. those arising from ultrashort-lived nuclides, heavy ion interactions and the combination of delayed and prompt methods. (author)

  14. Coagulation of charged particles in dust plasma

    International Nuclear Information System (INIS)

    One studied peculiarities of behaviour of small particles in dust plasma resulted on the one hand, from suppression of coagulation due to monopolar charging within the range of particle dimensions under the Debye radius of shielding and, on the other hand, from leveling of this case for particles of large dimensions. On the basis of similarity ratios one determined the range of parameters making linear approximation of particle charge dependence on their dimension true. In terms of the modified classical theory of coagulation in diffusion approximation one studied certain anomalies of behavior of dimension distribution of particles. It is determined that in contrast to the ordinary aerosol in dust plasma as time passes one may reduce dispersion of distribution and average dimensions of particles. For the first time one demonstrates the possibility to realize long-lived quasiliquid state of dust plasma associated with the anomalous behaviour of distribution function of coagulating charged particles according to dimensions

  15. Weak charges of charmed particles

    International Nuclear Information System (INIS)

    The matrix elements between the lowest states of the ΔC=1 weak charges are evaluated including the effect of SU4 breaking. The charges are obtained from the corresponding generators of the classification group by a unitary transformation U, which is factorized as the product of operators acting on a single quark: the breaking is naturally introduced by having different mixing parameters for the different quarks

  16. Robust statistical reconstruction for charged particle tomography

    Science.gov (United States)

    Schultz, Larry Joe; Klimenko, Alexei Vasilievich; Fraser, Andrew Mcleod; Morris, Christopher; Orum, John Christopher; Borozdin, Konstantin N; Sossong, Michael James; Hengartner, Nicolas W

    2013-10-08

    Systems and methods for charged particle detection including statistical reconstruction of object volume scattering density profiles from charged particle tomographic data to determine the probability distribution of charged particle scattering using a statistical multiple scattering model and determine a substantially maximum likelihood estimate of object volume scattering density using expectation maximization (ML/EM) algorithm to reconstruct the object volume scattering density. The presence of and/or type of object occupying the volume of interest can be identified from the reconstructed volume scattering density profile. The charged particle tomographic data can be cosmic ray muon tomographic data from a muon tracker for scanning packages, containers, vehicles or cargo. The method can be implemented using a computer program which is executable on a computer.

  17. New Charged Particles from Higgs Couplings

    CERN Document Server

    Cohen, Andrew G

    2012-01-01

    The recently reported observation of a new particle with mass about 125 GeV and couplings generally resembling those of the Standard Model Higgs boson provides a potential probe of the physics of electroweak symmetry breaking. Although the current data only provides hints, we suggest a particular combination of Higgs couplings as an assay for new charged particles connected with electroweak symmetry breaking, and construct a simple model with charge 5/3 quarks as a demonstration of its use.

  18. Measurement of the electrostatic charge in airborne particles: II - particle charge distribution of different aerosols

    Directory of Open Access Journals (Sweden)

    M. V. Rodrigues

    2006-03-01

    Full Text Available This work gives sequence to the study on the measurement of the electrostatic charges in aerosols. The particle charge classifier developed for this purpose and presented in the previous paper (Marra and Coury, 2000 has been used here to measure the particle charge distribution of a number of different aerosols. The charges acquired by the particles were naturally derived from the aerosol generation procedure itself. Two types of aerosol generators were used: the vibrating orifice generator and turntable Venturi plate generator. In the vibrating orifice generator, mono-dispersed particles were generated by a solution of water/ethanol/methylene blue, while in the rotating plate generator, six different materials were utilized. The results showed no clear dependence between electric charge and particle diameter for the mono-dispersed aerosol. However, for the poly-dispersed aerosols, a linear dependence between particle size and charge could be noticed.

  19. Phase diffusionless γ↔α transformations and their effect on physical, mechanical and corrosion properties of austenitic stainless steels irradiated with neutrons and charged particles

    Science.gov (United States)

    Maksimkin, O. P.

    2016-04-01

    The work presents relationships of γ→α' and α'→γ-transformations in reactor 12Cr18Ni10Ti and 08Cr16Ni11Mo3 austenitic stainless steels induced by cold work, irradiation and/or temperature. Energy and mechanical parameters of nucleation and development of deformation-induced martensitic α'-phase in the non-irradiated and irradiated steels are given. The mechanisms of localized static deformation were investigated and its effect on martensitic γ→α' transformation is determined. It has been shown that irradiation of 12Cr18Ni10Ti steel with heavy Kr ions (1.56MeV/nucleon, fluence of 1·1015 cm-2) results in formation of α'-martensite in near-surface layer of the sample. Results of systematic research on reversed α'→γ-transformation in austenitic metastable stainless steels irradiated with slow (VVR-K) and fast (BN-350) neutrons are presented. The effect of annealing on strength and magnetic characteristics was determined. It was found that at the temperature of 400 °C in the irradiated with neutrons samples (59 dpa) an increase of ferromagnetic α'-phase and microhardness was observed. The obtained results could be used during assessment of operational characteristics of highly irradiated austenitic steels during transportation and storage of Fuel Assemblies for fast nuclear reactors.

  20. Particles with non abelian charges

    CERN Document Server

    Bastianelli, Fiorenzo; Corradini, Olindo; Latini, Emanuele

    2013-01-01

    Efficient methods for describing non abelian charges in worldline approaches to QFT are useful to simplify calculations and address structural properties, as for example color/kinematics relations. Here we analyze in detail a method for treating arbitrary non abelian charges. We use Grassmann variables to take into account color degrees of freedom, which however are known to produce reducible representations of the color group. Then we couple them to a U(1) gauge field defined on the worldline, together with a Chern-Simons term, to achieve projection on an irreducible representation. Upon gauge fixing there remains a modulus, an angle parametrizing the U(1) Wilson loop, whose dependence is taken into account exactly in the propagator of the Grassmann variables. We test the method in simple examples, the scalar and spin 1/2 contribution to the gluon self energy, and suggest that it might simplify the analysis of more involved amplitudes.

  1. Discrete Element Modeling of Triboelectrically Charged Particles

    Science.gov (United States)

    Hogue, Michael D.; Calle, Carlos I.; Weitzman, Peter S.; Curry, David R.

    2008-01-01

    Tribocharging of particles is common in many processes including fine powder handling and mixing, printer toner transport and dust extraction. In a lunar environment with its high vacuum and lack of water, electrostatic forces are an important factor to consider when designing and operating equipment. Dust mitigation and management is critical to safe and predictable performance of people and equipment. The extreme nature of lunar conditions makes it difficult and costly to carry out experiments on earth which are necessary to better understand how particles gather and transfer charge between each other and with equipment surfaces. DEM (Discrete Element Modeling) provides an excellent virtual laboratory for studying tribocharging of particles as well as for design of devices for dust mitigation and for other purposes related to handling and processing of lunar regolith. Theoretical and experimental work has been performed pursuant to incorporating screened Coulombic electrostatic forces into EDEM, a commercial DEM software package. The DEM software is used to model the trajectories of large numbers of particles for industrial particulate handling and processing applications and can be coupled with other solvers and numerical models to calculate particle interaction with surrounding media and force fields. While simple Coulombic force between two particles is well understood, its operation in an ensemble of particles is more complex. When the tribocharging of particles and surfaces due to frictional contact is also considered, it is necessary to consider longer range of interaction of particles in response to electrostatic charging. The standard DEM algorithm accounts for particle mechanical properties and inertia as a function of particle shape and mass. If fluid drag is neglected, then particle dynamics are governed by contact between particles, between particles and equipment surfaces and gravity forces. Consideration of particle charge and any tribocharging and

  2. Charged particle concepts for fog dispersion

    Science.gov (United States)

    Frost, W.; Collins, F. G.; Koepf, D.

    1981-01-01

    Charged particle techniques hold promise for dispersing warm fog in the terminal area of commercial airports. This report focuses on features of the charged particle technique which require further study. The basic physical principles of the technique and the major verification experiments carried out in the past are described. The fundamentals of the nozzle operation are given. The nozzle characteristics and the theory of particle charging in the nozzle are discussed, including information from extensive literature on electrostatic precipitation relative to environmental pollution control and a description of some preliminary reported analyses on the jet characteristics and interaction with neighboring jets. The equation governing the transfer of water substances and of electrical charge is given together with a brief description of several semi-empirical, mathematical expressions necessary for the governing equations. The necessary ingredients of a field experiment to verify the system once a prototype is built are described.

  3. Towards a microscopic theory of particle charging

    CERN Document Server

    Bronold, Franz X; Kersten, H; Deutsch, H

    2009-01-01

    We recently questioned the treatment of a dust particle as a perfect absorber for electrons and ions and proposed a surface model for the charge of a dust particle in a quiescent plasma which combines the microscopic physics at the grain boundary (sticking into and desorption from external surface states) with the macrophysics of the discharge (plasma collection fluxes). Within this model the charge and partial screening of the particle can be calculated without relying on the condition that the total electron collection flux balances on the grain surface the total ion collection flux. Grain charges obtained from our approach compared favorably with experimental data. The purpose of this paper is to describe our model in more detail, in particular, the hypotheses on which it is built, contrast it with the standard charging models based on flux balancing on the grain surface, and to analyze additional experimental data.

  4. Fractionally charged particles in cosmic rays

    CERN Document Server

    Bashindzhagyan, George

    2016-01-01

    The results of many experiments on a search of fractionally charged particles in cosmic rays have been reviewed. The registered by ATIC and PAMELA experiments change of the proton energy spectrum at about 250 GeV can be explained if fractionally charged particles with another energy spectrum slope actually mixed with protons but cannot be separated because of a strong dE/dx fluctuations. The performed simulations show that multilayer detectors can seriously help in such separation. In the Aragats experiment performed using multilayer proportional counter combined with hadron calorimeter a group of 4e/3 like events with unexpectedly high average energy has been registered. It could be explained by their different from regular hadrons energy spectrum. The ATIC experiment ionization spectrum in single charged particle area has been examined. An interesting bump in 2e/3 charge region was observed. The events in the bump have very different from regular protons angular distribution.

  5. Electro-optical detection of charged particles

    CERN Document Server

    Semertzidis, Y K; Kowalski, L A; Kraus, D E; Larsen, R; Lazarus, D M; Magurno, B; Nikas, D; Ozben, C; Srinivasan-Rao, T; Tsang, Thomas

    2000-01-01

    We have made the first observation of a charged particle beam by means of its electro-optical effect on the polarization of laser light in a LiNbO sub 3 crystal. The modulation of the laser light during the passage of a pulsed electron beam was observed using a fast photodiode and a digital oscilloscope. The fastest rise time measured, 120 ps, was obtained in the single shot mode and was limited by the bandwidth of the oscilloscope and the associated electronics. This technology holds good for detectors of greatly improved spatial and temporal resolution for single relativistic charged particles as well as particle beams.

  6. Why do particle clouds generate electric charges?

    Science.gov (United States)

    Pähtz, T.; Herrmann, H. J.; Shinbrot, T.

    2010-05-01

    Grains in desert sandstorms spontaneously generate strong electrical charges; likewise volcanic dust plumes produce spectacular lightning displays. Charged particle clouds also cause devastating explosions in food, drug and coal processing industries. Despite the wide-ranging importance of granular charging in both nature and industry, even the simplest aspects of its causes remain elusive, because it is difficult to understand how inert grains in contact with little more than other inert grains can generate the large charges observed. Here, we present a simple yet predictive explanation for the charging of granular materials in collisional flows. We argue from very basic considerations that charge transfer can be expected in collisions of identical dielectric grains in the presence of an electric field, and we confirm the model's predictions using discrete-element simulations and a tabletop granular experiment.

  7. Search milli-charged particles at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Langeveld, W.G.J. [Stanford Univ., CA (United States)

    1997-01-01

    Particles with electric charge q {triple_bond} Qe {le} 10{sup -3} e and masses in the range 1-1000 MeV/c{sup 2} are not excluded by present experiments or by astrophysical or cosmological arguments. A beam dump experiment uniquely suited to the detection of such {open_quotes}milli-charged{close_quotes} particles has been carried out at SLAC, utilizing the short-duration pulses of the SLC electron beam to establish a tight coincidence window for the signal. The detector, a large scintillation counter sensitive to very small energy depositions, provided much greater sensitivity than previous searches. Analysis of the data leads to the exclusion of a substantial portion of the charge-mass plane. In this report, a preliminary mass-dependent upper limit is presented for the charge of milli-charged particles, ranging from Q = 1.7 x 10{sup -5} at milli-charged particle mass 0.1 MeV/c{sup 2} to Q = 9.5 x 10{sup -4} at 100 MeV/c{sup 2}.

  8. Bibliography of integral charged particle nuclear data

    International Nuclear Information System (INIS)

    This publication is the second supplement to the archival edition of the National Nuclear Data Center's charged-particle bibliography. This supplement contains citations to all references scanned since March 15, 1981, and all corrections and additions to previous citations, and indexes all data received in the international exchanged format (EXFOR). The primary goal of the bibliography has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged-particle cross section data and to provide an index of data exchanged among the members. In 1980, coverage was expanded to include differential data relevant to charged-particle-induced neutron-source reactions

  9. Integral charged particle nuclear data bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Holden, N.E.; Ramavataram, S.

    1989-12-01

    This publication is the annual supplement to the first edition published in 1984. The primary goal of this publication has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged--particle cross section data. Included in this paper is a partial list of other bibliographies relevant to charged-particle-induced reaction data and a source list of nuclear data bibliographies, complications, and cumulative, earlier versions are also shown in the tables. This publication makes use of a modification to the database of the Nuclear Structure References (NSR) file. This modification allows the retrieval of integral charged particle nuclear data entries from the NSR file. In recent years, the presentation of various sections was changed, as a result of users' suggestions. The authors continue to welcome users' comments.

  10. Integral charged particle nuclear data bibliography

    International Nuclear Information System (INIS)

    This publication is the annual supplement to the first edition published in 1984. The primary goal of this publication has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged--particle cross section data. Included in this paper is a partial list of other bibliographies relevant to charged-particle-induced reaction data and a source list of nuclear data bibliographies, complications, and cumulative, earlier versions are also shown in the tables. This publication makes use of a modification to the database of the Nuclear Structure References (NSR) file. This modification allows the retrieval of integral charged particle nuclear data entries from the NSR file. In recent years, the presentation of various sections was changed, as a result of users' suggestions. The authors continue to welcome users' comments

  11. Position sensitive detector of magnetically charged particles

    International Nuclear Information System (INIS)

    Two variants of coordinate detectors of magnetically charged paticles based on the utilization of transducers with Josephson transitions are proposed. The system of data acquisition and processing is built up in the CAMAC standard. The helium cryostat diagram is presented. The detector resolution time and dead time constitute 1 μs. Methods of detection of magnetically charged particles used in the above detectors are expected to be more effective, as compared to ionization method and other indirect methods

  12. Cataract production in mice by heavy charged particles

    International Nuclear Information System (INIS)

    The cataractogenic effects of heavy charged particles have been evaluated in mice in relation to dose and ionization density (LET/sub infinity/). The study was undertaken due to the high potential for eye exposures to HZE particles among SPS personnel working in outer space. This has made it imperative that the relative biological effectiveness (RBE) in relation to LET/sub infinity/ for various particles be defined so that appropriate quality factors (Q) could be assigned for estimation of risk. Although mice and men differ in susceptibility to radiation-induced cataracts, the results from this project should assist in defining appropriate quality factors in relation to LET/sub infinity/, particle mass, charge, or velocity. Evaluation of results indicated that : (1) low single doses (5 to 20 rad) of iron (56Fe) or argon (40Ar) particles are cataractogenic at 11 to 18 months after irradiation; (2) onset and density of the opacification are dose related; (3) cataract density (grade) at 9, 11, 13, and 16 months after irradiation shows partial LET/sub infinity/-dependence; and (4) the severity of cataracts is reduced significantly when 417 rad of 60Co gamma radiation is given in 24 weekly 17 rad fractions compared to giving this radiation as a single dose, but cataract severity is not reduced by fractionation of 12C doses over 24 weeks

  13. Fog camera to visualize ionizing charged particles

    International Nuclear Information System (INIS)

    The human being can not perceive the different types of ionizing radiation, natural or artificial, present in the nature, for what appropriate detection systems have been developed according to the sensibility to certain radiation type and certain energy type. The objective of this work was to build a fog camera to visualize the traces, and to identify the trajectories, produced by charged particles with high energy, coming mainly of the cosmic rays. The origin of the cosmic rays comes from the solar radiation generated by solar eruptions where the protons compose most of this radiation. It also comes, of the galactic radiation which is composed mainly of charged particles and gamma rays that comes from outside of the solar system. These radiation types have energy time millions higher that those detected in the earth surface, being more important as the height on the sea level increases. These particles in their interaction produce secondary particles that are detectable by means of this cameras type. The camera operates by means of a saturated atmosphere of alcohol vapor. In the moment in that a charged particle crosses the cold area of the atmosphere, the medium is ionized and the particle acts like a condensation nucleus of the alcohol vapor, leaving a visible trace of its trajectory. The built camera was very stable, allowing the detection in continuous form and the observation of diverse events. (Author)

  14. Control microprocessor system for charge particle channeling

    International Nuclear Information System (INIS)

    Control microprocessor systems are widely applied not only in designing industrial robots but in providing functioning of different experimental plants. The experiment control system for charge particle channeling has been considered in the paper. Flexibility, relatively low cost and high reliability are advantages of these systems

  15. Studying Charged Particle Optics: An Undergraduate Course

    Science.gov (United States)

    Ovalle, V.; Otomar, D. R.; Pereira, J. M.; Ferreira, N.; Pinho, R. R.; Santos A. C. F.

    2008-01-01

    This paper describes some computer-based activities to bring the study of charged particle optics to undergraduate students, to be performed as a part of a one-semester accelerator-based experimental course. The computational simulations were carried out using the commercially available SIMION program. The performance parameters, such as the focal…

  16. Bmad: A relativistic charged particle simulation library

    International Nuclear Information System (INIS)

    Bmad is a subroutine library for simulating relativistic charged particle beams in high-energy accelerators and storage rings. Bmad can be used to study both single and multi-particle beam dynamics using routines to track both particles and macroparticles. Bmad has various tracking algorithms including Runge-Kutta and symplectic (Lie algebraic) integration. Various effects such as wakefields, and radiation excitation and damping can be simulated. Bmad has been developed in a modular, object-oriented fashion to maximize flexibility. Interface routines allow Bmad to be called from C/C++ as well as Fortran programs. Bmad is well documented. Every routine is individually annotated, and there is an extensive manual

  17. Charged Particles' Tunneling from Noncommutative Charged Black Hole

    CERN Document Server

    Mehdipour, S Hamid

    2010-01-01

    We apply the tunneling process of charged massive particles through the quantum horizon of a Reissner-Nordstr\\"om black hole in a new noncommutative gravity scenario. In this model, the tunneling amplitude on account of noncommutativity influences in the context of coordinate coherent states is modified. Our calculation points out that the emission rate satisfies the first law of black hole thermodynamics and is consistent with an underlying unitary theory.

  18. Charged particles' tunneling from a noncommutative charged black hole

    OpenAIRE

    Mehdipour, S. Hamid

    2010-01-01

    We apply the tunneling process of charged massive particles through the quantum horizon of a Reissner-Nordstrom black hole in a new noncommutative gravity scenario. In this model, the tunneling amplitude on account of noncommutativity influences in the context of coordinate coherent states is modified. Our calculation points out that the emission rate satisfies the first law of black hole thermodynamics and is consistent with an underlying unitary theory.

  19. Space-charge dynamics of polymethylmethacrylate under electron beam irradiation

    CERN Document Server

    Gong, H; Ong, C K

    1997-01-01

    Space-charge dynamics of polymethylmethacrylate (PMMA) under electron beam irradiation has been investigated employing a scanning electron microscope. Assuming a Gaussian space-charge distribution, the distribution range (sigma) has been determined using a time-resolved current method in conjunction with a mirror image method. sigma is found to increase with irradiation time and eventually attain a stationary value. These observations have been discussed by taking into account radiation-induced conductivity and charge mobility. (author)

  20. Acceleration of charged particles in laser beam

    Directory of Open Access Journals (Sweden)

    M.J. Małachowski

    2009-12-01

    Full Text Available Purpose: The aim of this paper was to find parameters of the laser and maser beams in numerical ways with additionally applied external static axial magnetic field which satisfies the proper conditions for charged particle acceleration.Design/methodology/approach: The set acceleration was designed in order to obtain the possible high kinetic energy of the charged particles in the controllable manner. This was achieved applying a circularly polarized high intensity laser beam and a static axial magnetic field, both acting on the particle during the proper period.Findings: The quantitative illustrations of the calculation results, in a graphical form enabled to discuss the impact of many parameters on the acceleration process of the electrons and protons. We have found the impact of the Doppler Effect on the acceleration process to be significant. Increase in laser or maser beam intensity results in particle’s energy increase and its trajectory dimension. However, increase in external magnetic field results in shrinking of the helical trajectories. It enables to keep the particle inside the laser beam.Research limitations/implications: Limits in the energy of accelerated particles arise from the limitsin up-to-date available laser beam energy and the beam diameters.Originality/value: The authors show the parameters of the circularly polarized laser beam which should be satisfied in order to obtain the desired energy of the accelerated particles. The influence of the magnetic field strength is also shown.

  1. The formation of negatively charged particles in thermoemission plasmas

    Science.gov (United States)

    Vishnyakov, V. I.; Dragan, G. S.; Florko, A. V.

    2008-01-01

    The results of measuring the charges of the magnesium oxide particles formed near a block of metallic magnesium burning in air are presented. It has been found that, apart from positively charged magnesium oxide particles, there are negatively charged particles in the thermoemission plasma of the burning products. It has been shown that within the framework of the model of neutralizing charges, the oxide particles can acquire unlike charges in the thermoemission plasma. The calculations agree with the experimental data.

  2. The formation of negatively charged particles in thermoemission plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Vishnyakov, V. I., E-mail: pipeaes@te.net.ua; Dragan, G. S.; Florko, A. V. [Mechnikov Odessa National University (Ukraine)

    2008-01-15

    The results of measuring the charges of the magnesium oxide particles formed near a block of metallic magnesium burning in air are presented. It has been found that, apart from positively charged magnesium oxide particles, there are negatively charged particles in the thermoemission plasma of the burning products. It has been shown that within the framework of the model of neutralizing charges, the oxide particles can acquire unlike charges in the thermoemission plasma. The calculations agree with the experimental data.

  3. The formation of negatively charged particles in thermoemission plasmas

    International Nuclear Information System (INIS)

    The results of measuring the charges of the magnesium oxide particles formed near a block of metallic magnesium burning in air are presented. It has been found that, apart from positively charged magnesium oxide particles, there are negatively charged particles in the thermoemission plasma of the burning products. It has been shown that within the framework of the model of neutralizing charges, the oxide particles can acquire unlike charges in the thermoemission plasma. The calculations agree with the experimental data

  4. Born expansions for charged particle scattering

    International Nuclear Information System (INIS)

    High-order terms in Born expansions of scattering amplitudes in powers of charge are frequently divergent when long-range Coulomb interactions are present asymptotically. Expansions which are free from these logarithmic divergences have been constructed recently. This paper illustrates these expansions with the simplest example, namely the non-relativistic Rutherford scattering of two charged particles. This approach represents an adequate framework for the calculation of transition amplitudes and a comprehensive starting point for the development of consistent perturbation approximations in multi-channel descriptions of strongly interacting atomic systems

  5. Microscopic visualization of a biological response to charged particle traversal

    Science.gov (United States)

    Taucher-Scholz, G.; Jakob, B.; Becker, G.; Scholz, M.

    2003-08-01

    Understanding the molecular mechanisms underlying biological effects of charged particle radiation has become increasingly important in view of the use of ion beams in tumor therapy. Elucidating how the enhanced efficiency of densely ionizing radiation in cell killing is related to the initial causative lesions, namely DNA double-strand breaks, constitutes a major task in radiobiology. The inhomogeneous spatial distribution of energy deposition leading to the induction of more complex and less reparable DNA lesions is the basis for high-LET effects. But the cellular response to radiation damage also involves the interplay between repair and signal transduction proteins with the aim of coordinating the processing of DNA damage and cell cycle progression to allow time for repair. Charged particles are used as a probe for the production of localized subcellular damage to study these aspects of the biological response to ionizing radiation. Immunocytochemical techniques applied in combination with confocal laser microscopy allow to monitor the relocalization of DNA damage response proteins within individual nuclei following irradiation. In particular, the rapid accumulation of the signalling protein p21 at sites of heavy ion-induced DNA damage reflects the microscopic distribution of dose deposited within nuclei of irradiated human fibroblasts. The biological response pattern for p21 is presented for high and low energy ion beams, involving different particle species and representing a wide range of radiation qualities.

  6. The prospects for charged particle uses in oncology

    International Nuclear Information System (INIS)

    Prospects and problems of proton therapy by means of accelerators are considered. Approaches to the solution of the problems concerning operation modes of the accelerator are formulated. It is shown that despite vivid advantage of charged particles for their applied use in beam therapy of malignant tumour it is necessary to solve two problems: extraction of special beams meeting strict medical requirements and development of technology of irradiation of malignant tumours of different localizations and construction of special equipment for execution of this technology. Engineering-technological shortcomings of proton therapy and medical-biological problems requiring reglamentation are enumerated

  7. Method for charged particle beam acceleration

    International Nuclear Information System (INIS)

    The method of charged particle beam acceleration based on its resonance interaction with electromagnetic field of travelling wave is suggested. The electron beam is injected into waveguide in which longitudinal magnetic field and electromagnetic wave are excited. With the purpose of reducing HF-power losses in the waveguide walls, the azimuthal particle motion is synchronized with azimuthal change of longitudinal component of electric field of the accelerating electromagnetic wave. The suggested method permits to increase the efficiency and shunting resistance of the accelerating waveguide by reducing its boundary surface

  8. Collective aspects of charged particle track structure

    International Nuclear Information System (INIS)

    A plasmon generated by a swift charged particle constitutes a coherent excitation about the particle track. We discuss the representation of collective modes in impact parameter space when created by a swift ion or a fast electron, and the decay of these modes into localized excitations. Several alternative spatial representations are considered. We show that the high spatial resolution found in secondary electron emission measurements with scanning electron microscopy is consistent with the existence of the plasmon as an intermediary between the fast incident electron and the measured secondary electrons. 24 refs., 6 figs

  9. Charge State Model of Solar Energetic Particles

    Science.gov (United States)

    Del Peral, L.; Pérez-Peraza, J. A.; Rodríguez Frías, M. D.

    2013-05-01

    Charge states of heavy ions in Solar Energetic Particle (SEP) events observed at the Earth's neighborhood with experiments on board satellites give us information about physical properties of plasma where acceleration occurs. SEP detection is performed near the Earth, therefore not only physical condition of the plasma source of accelerated particles have to be taken into account. We have developed a charge state model in order to explain the evolution of particle charge states under solar acceleration. Charge-interchange processes between the accelerated ions and the plasma matter in the acceleration region are considered on basis of electron loss and capture cross sections at high energies. We have applied the model to observational data from satellites measuring charge states of SEPs. In contrast with other models that use ionization and recombination cross-sections that require application of thermal equilibrium, our model assumes that the acceleration is so fast that thermal equilibrium can not be applied to the change interchange processes. Therefore we employ in our model high energy cross-sections for electron capture and loss, since the population which is being accelerated acquires a non-thermal spectrum. We have developed temperature dependent cross-sections. Acceleration begins from a thermal distribution. As soon as the particles increase their energy by the acceleration process, they acquire an energy spectrum which differs from the Maxwellian thermal one while interacting with the background thermal matter. Figure 1 presents the results of our model that fit experimental charge states of Fe ions from two impulsive SEP events detected by the SEPICA satellite in July 1999. We obtain good fitting for source temperature of 1.8 \\cdot 106 K and density of 5\\cdot108 cm-3 and acceleration efficiency of 1.8\\cdot 10-2 s-1 for the July 20th 1999 event and 3.3\\cdot 10-2 s-1 for the July 3rd 1999. Good concordance between experimental data and our model have

  10. Geometrical charged-particle optics. 2. ed.

    Energy Technology Data Exchange (ETDEWEB)

    Rose, Harald [Technische Univ. Darmstadt (Germany). Inst. fuer Angewandte Physik

    2013-03-01

    Provides a unique theoretical treatment of charged-particle optics. Displays novel unpublished results on several topics. Provides insight into the properties of charged-particle devices. Treats wave optical properties of the electron. Presents the resolution limit of electron microscopes and novel theoretical treatment of the Stern-Gerlach effect. This second edition is an extended version of the first edition of Geometrical Charged-Particle Optics. The updated reference monograph is intended as a guide for researchers and graduate students who are seeking a comprehensive treatment of the design of instruments and beam-guiding systems of charged particles and their propagation in electromagnetic fields. Wave aspects are included in this edition for explaining electron holography, the Aharanov-Bohm effect and the resolution of electron microscopes limited by diffraction. Several methods for calculating the electromagnetic field are presented and procedures are outlined for calculating the properties of systems with arbitrarily curved axis. Detailed methods are presented for designing and optimizing special components such as aberration correctors, spectrometers, energy filters monochromators, ion traps, electron mirrors and cathode lenses. In particular, the optics of rotationally symmetric lenses, quadrupoles, and systems composed of these elements are discussed extensively. Beam properties such as emittance, brightness, transmissivity and the formation of caustics are outlined. Relativistic motion and spin precession of the electron are treated in a covariant way by introducing the Lorentz-invariant universal time and by extending Hamilton's principle from three to four spatial dimensions where the laboratory time is considered as the fourth pseudo-spatial coordinate. Using this procedure and introducing the self action of the electron, its accompanying electromagnetic field and its radiation field are calculated for arbitrary motion. In addition, the Stern

  11. Automated control system in charged particle accelerators

    International Nuclear Information System (INIS)

    A general approach to the design of automated radiation safety systems at charged particle accelerators is described. Parameters of high-energy electron accelerators of the Kharkov Physics and Engineering Institute are presented. Characteristics of the surrounding radiation fields are given. Ionizing radiation transducers which can be used in automated systems are considered. Local radiation monitoring station based on the LUE-2000 accelerator of the institute is described. 9 refs.; 4 figs.; 1 tab

  12. Controlling Charged Particles with Inhomogeneous Electrostatic Fields

    Science.gov (United States)

    Herrero, Federico A. (Inventor)

    2016-01-01

    An energy analyzer for a charged-particle spectrometer may include a top deflection plate and a bottom deflection plate. The top and bottom deflection plates may be non-symmetric and configured to generate an inhomogeneous electrostatic field when a voltage is applied to one of the top or bottom deflection plates. In some instances, the top and bottom deflection plates may be L-shaped deflection plates.

  13. Charged particle layers in the Debye limit

    International Nuclear Information System (INIS)

    We develop an equivalent of the Debye-Hueckel weakly coupled equilibrium theory for layered classical charged particle systems composed of one single charged species. We consider the two most important configurations, the charged particle bilayer and the infinite superlattice. The approach is based on the link provided by the classical fluctuation-dissipation theorem between the random-phase approximation response functions and the Debye equilibrium pair correlation function. Layer-layer pair correlation functions, screened and polarization potentials, static structure functions, and static response functions are calculated. The importance of the perfect screening and compressibility sum rules in determining the overall behavior of the system, especially in the r→∞ limit, is emphasized. The similarities and differences between the quasi-two-dimensional bilayer and the quasi-three-dimensional superlattice are highlighted. An unexpected behavior that emerges from the analysis is that the screened potential, the correlations, and the screening charges carried by the individual layers exhibit a marked nonmonotonic dependence on the layer separation

  14. Light Charged Particles as Gateway to Hyperdeformation

    International Nuclear Information System (INIS)

    The Euroball-IV γ -detector array, equipped with the ancillary charged particle detector array DIAMANT was used to study the residues of the fusion reaction 64Ni + 64Ni → 128Ba at Ebeam = 255 and 261 MeV, in an attempt to reach the highest angular momentum and verify the existence of predicted hyperdeformed rotational bands. No discrete hyperdeformed bands were identified, but nevertheless a breakthrough was obtained through a systematic search for rotational ridge structures with very large moments of inertia J(2) ≥ 100 ℎ2 MeV(-1), in agreement with theoretical predictions for hyperdeformed shapes. Evidence for hyperdeformation was obtained by charged particle + γ -ray gating, selecting triple correlated ridge structures in the continuum of each of the nuclei, 118Te, 124Xe and 124,125Cs. In 7 additional nuclei, rotational ridges were also identified with J(2) = 71-77 ℎ2 MeV(-1), which most probably correspond to superdeformed shape. The angular distributions of the emitted charged particles show an excess in forward direction over expectations from pure compound evaporation, which may indicate that in-complete fusion plays an important role in the population of very elongated shapes. (author)

  15. Determining the charged particle energy losses with usage of transmutation isotopes

    CERN Document Server

    Didik, V A; Skoryatina, E A; Kozlovskij, V V

    2002-01-01

    The method for determining the charged particles energy losses in a solid body, based on the comparison of the transmutation isotopes profiles, formed by irradiation with the particles of various energies, is proposed. The protons energy losses in copper were determined by the described method. The irradiation was performed on a cyclotron by the energies of 8, 10, 12.5, 15.5 and 18 MeV. The obtained results agree well with the published data

  16. Motion of charged particles in the magnetosphere

    International Nuclear Information System (INIS)

    The adiabatic motion of charged particles in the magnetosphere has been investigated using Mead-Fairfield magnetospheric field model (Mead and Fairfield, 1975). Since the motion of charged particles in a dipolar field geometry is well understood, we bring out in this paper some important features in characteristic motion due to non-dipolar distortions in the field geometry. We look at the tilt averaged picture of the field configuration and estimate theoretically the parameters like bounce period, longitudinal invariant and the bounce averaged drift velocities of the charged particle in the Mead-Fairfield field geometry. These parameters are evaluated as a function of pitch angle and azimuthal position in the region of ring current (5 to 7 Earth radii from the centre of the Earth) for four ranges of magnetic activity. At different longitudes the non-dipolar contribution as a percentage of dipole value in bounce period and longitudinal invariant shows maximum variation for particles close to 900 pitch angles. For any low pitch angle, these effects maximize at the midnight meridian. The radial component of the bounce averaged drift velocity is found to be greatest at the dawn-dusk meridians and the contribution vanishes at the day and midnight meridians for all pitch angles. In the absence of tilt-dependent terms in the model, the latitudinal component of the drift velocity vanishes. On the other hand, the relative non-dipolar contribution to bounce averaged azimuthal drift velocity is very high as compared to similar contribution in other characteristic parameters of particle motion. It is also shown that non-dipolar contribution in bounce period, longitudinal invariant and bounce averaged drift velocities increases in magnitude with increase in distance and magnetic activity. (orig.)

  17. Experimental research of thermoemission charging of metal particles

    International Nuclear Information System (INIS)

    Original experimental methods of thermoemission charge determination of a spherical metallic particle surrounded by the condensed disperse phase are proposed. The analytical dependence of the particle charge on time is found, and its relaxation time is determined

  18. Metastable states of plasma particles close to a charged surface

    International Nuclear Information System (INIS)

    The free energy of the plasma particles and the charged surface that form an electroneutral system is calculated on the basis of the Poisson-Boltzmann equation. It is shown that, owing to correlation of light plasma particles near the charged surface and close to heavy particles of high charge, there can be metastable states in plasma. The corresponding phase charts of metastable states of the separate components of plasma, and plasma as a whole, are constructed. These charts depend on temperature, the charge magnitude, the size of the particles, and the share of the charge of the light carriers out of the total charge of the plasma particles

  19. Radiation reaction for a massless charged particle

    Energy Technology Data Exchange (ETDEWEB)

    Kazinski, P O; Sharapov, A A [Physics Faculty, Tomsk State University, Tomsk, 634050 (Russian Federation)

    2003-07-07

    We derive effective equations of motion for a massless charged particle coupled to the dynamical electromagnetic field with regard to the radiation back reaction. It is shown that unlike the massive case, not all the divergences resulting from the self-action of the particle are Lagrangian, i.e., can be cancelled out by adding appropriate counterterms to the original action. Besides, the order of renormalized differential equations governing the effective dynamics turns out to be greater than the order of the corresponding Lorentz-Dirac equation for a massive particle. For the case of a homogeneous external field, the first radiative correction to the Lorentz equation is explicitly derived via the reduction of order procedure.

  20. Radiation reaction for a massless charged particle

    CERN Document Server

    Kazinski, P O

    2003-01-01

    We derive effective equations of motion for a massless charged particle coupled to the dynamical electromagnetic field having regard to the radiation back reaction. It is shown that unlike the massive case not all the divergences resulting from the self-action of the particle are Lagrangian, i.e. can be canceled out by adding appropriate counterterms to the original action. Besides, the order of renormalized differential equations governing the effective dynamics turns out to be greater than the order of the corresponding Lorentz-Dirac equation for a massive particle. For the case of homogeneous external field the first radiative correction to the Lorentz equation is explicitly derived via the reduction of order procedure.

  1. Radiation reaction for a massless charged particle

    International Nuclear Information System (INIS)

    We derive effective equations of motion for a massless charged particle coupled to the dynamical electromagnetic field with regard to the radiation back reaction. It is shown that unlike the massive case, not all the divergences resulting from the self-action of the particle are Lagrangian, i.e., can be cancelled out by adding appropriate counterterms to the original action. Besides, the order of renormalized differential equations governing the effective dynamics turns out to be greater than the order of the corresponding Lorentz-Dirac equation for a massive particle. For the case of a homogeneous external field, the first radiative correction to the Lorentz equation is explicitly derived via the reduction of order procedure

  2. Radiation reaction for a massless charged particle

    Science.gov (United States)

    Kazinski, P. O.; Sharapov, A. A.

    2003-07-01

    We derive effective equations of motion for a massless charged particle coupled to the dynamical electromagnetic field with regard to the radiation back reaction. It is shown that unlike the massive case, not all the divergences resulting from the self-action of the particle are Lagrangian, i.e., can be cancelled out by adding appropriate counterterms to the original action. Besides, the order of renormalized differential equations governing the effective dynamics turns out to be greater than the order of the corresponding Lorentz-Dirac equation for a massive particle. For the case of a homogeneous external field, the first radiative correction to the Lorentz equation is explicitly derived via the reduction of order procedure.

  3. Development of Theoretical Modeling of Point Radiation Defects, Cascades and Sub-Cascades Formation in Diatomic Materials (AI2O3) Irradiated by Fast Charged Particles on Accelerators and Fast Neutrons in Atomic Reactors

    International Nuclear Information System (INIS)

    The main aim of this presentation is a description of modern theoretical models and obtained numerical results for radiation damage production inculing point defects, cascade and sub-cascade formations in different monoatomic materials irradiated by fast ions and fast neutrons taking into account elastic and inelastic processes. The special topic of this presentation is oriented on the theoretical modeling and numerical calculations of radiation damage formation (point defects, cascades and subcascades) in diatomic materials (Al2O3) irradiated by fast charged paricles on accelarators and fast neutrons in atomic reactors using exested nuclear data base

  4. Scanning system for charged and neutral particle beams

    International Nuclear Information System (INIS)

    The present invention aims at providing a simple and reliable method and a reliable device for irradiating a confined volume of matter, preferably at great depth, with a beam of high energy charged or neutral particles. The basic feature of the invention is that the particle beam coming from a radiation source of charged particles is scanned electrically in two orthogonal directions, and that the beam scanned in one plane is deflected in space. For most practical purposes it is important that the radiation source is of small extension. Such a radiation source is realized by means of a beam optical system that includes two scanning magnets each of which admits scanning of the particle beam in one of two orthogonal planes. The beam scanned in one of the planes leaves the associated scanning magnet from an effective scanning centre. The optical system also includes a deflection magnet disposed between the scanning magnets for deflecting the path of the beam in space. By utilizing the optical properties of the deflection magnet in such a way that the deflection magnet produces an image of the effective scanning centre of the first scanning magnet which coincides with the effective scanning centre of the second scanning magnet, the beam scanned in two orthogonal planes will radiate isotropically from the scanning centre of the second scanning magnet. By using the deflection magnet a compact scanning system with a small distance between the scanning centres of the scanning magnets is obtained

  5. A chemical analyzer for charged ultrafine particles

    Directory of Open Access Journals (Sweden)

    S. G. Gonser

    2013-04-01

    Full Text Available New particle formation is a frequent phenomenon in the atmosphere and of major significance for the earth's climate and human health. To date the mechanisms leading to the nucleation of particles as well as to aerosol growth are not completely understood. A lack of appropriate measurement equipment for online analysis of the chemical composition of freshly nucleated particles is one major limitation. We have developed a Chemical Analyzer for Charged Ultrafine Particles (CAChUP capable of analyzing particles with diameters below 30 nm. A bulk of size separated particles is collected electrostatically on a metal filament, resistively desorbed and consequently analyzed for its molecular composition in a time of flight mass spectrometer. We report of technical details as well as characterization experiments performed with the CAChUP. Our instrument was tested in the laboratory for its detection performance as well as for its collection and desorption capabilities. The manual application of known masses of camphene (C10H16 to the desorption filament resulted in a detection limit between 0.5 and 5 ng, and showed a linear response of the mass spectrometer. Flow tube experiments of 25 nm diameter secondary organic aerosol from ozonolysis of alpha-pinene also showed a linear relation between collection time and the mass spectrometer's signal intensity. The resulting mass spectra from the collection experiments are in good agreement with published work on particles generated by the ozonolysis of alpha-pinene. A sensitivity study shows that the current setup of CAChUP is ready for laboratory measurements and for the observation of new particle formation events in the field.

  6. Sound from charged particles in liquids

    International Nuclear Information System (INIS)

    Two directions of sound application appearing during the charged particles passing through liquid - in biology and for charged particles registration are considered. Application of this sound in radiology is determined by a contribution of its hypersound component (approximately 109 Hz) to radiology effect of ionizing radiation on micro-organisms and cells. Large amplitudes and pressure gradients in a hypersound wave have a pronounced destructive breaking effect on various microobjects (cells, bacteria, viruses). An essential peculiarity of these processes is the possibility of control by choosing conditions changing hypersound generation, propagation and effect. This fact may lead not only to the control by radiaiton effects but also may explain and complete the analogy of ionizing radiation and ultrasound effect on bioobjects. The second direction is acoustic registration of passing ionizing particles. It is based on the possibility of guaranteed signal reception from a shower with 1015-1016 eV energy in water at distances of hundreds of meters. Usage of acoustic technique for neutrino registration in the DUMAND project permits to use a detecting volume of water with a mass of 109 t and higher

  7. Simulation of irradiation effects by charged particles

    International Nuclear Information System (INIS)

    After a description of the elementary damages made by neutrons, ions and high energy electrons, simulations (by ions or electrons accelerator, and by electronic microscopy) of neutrons damages by ions or electrons are presented for reactor fuel assemblies and reactor structure materials with a short comparison between simulation and real comportment. (A.B.)

  8. Alpha particles diffusion due to charge changes

    Energy Technology Data Exchange (ETDEWEB)

    Clauser, C. F., E-mail: cesar.clauser@ib.edu.ar; Farengo, R. [Centro Atómico Bariloche and Instituto Balseiro, Comisión Nacional de Energía Atómica and Universidad Nacional de Cuyo, Av. Bustillo 9500, 8400 Bariloche (Argentina)

    2015-12-15

    Alpha particles diffusion due to charge changes in a magnetized plasma is studied. Analytical calculations and numerical simulations are employed to show that this process can be very important in the pedestal-edge-SOL regions. This is the first study that presents clear evidence of the importance of atomic processes on the diffusion of alpha particles. A simple 1D model that includes inelastic collisions with plasma species, “cold” neutrals, and partially ionized species was employed. The code, which follows the exact particle orbits and includes the effect of inelastic collisions via a Monte Carlo type random process, runs on a graphic processor unit (GPU). The analytical and numerical results show excellent agreement when a uniform background (plasma and cold species) is assumed. The simulations also show that the gradients in the density of the plasma and cold species, which are large and opposite in the edge region, produce an inward flux of alpha particles. Calculations of the alpha particles flux reaching the walls or divertor plates should include these processes.

  9. Scanning of irradiated silicon detectors using $\\alpha$ particles and low energy protons

    CERN Document Server

    Casse, G L; Glaser, M; Kohout, Z; Konícek, J; Lemeilleur, F; Leroy, C; Linhart, V; Mares, J J; Pospísil, S; Roy, P; Sopko, B; Sinor, M; Svejda, J; Vorobel, V; Wilhelm, I

    1999-01-01

    In a spectroscopic study of non-irradiated and proton-irradiated silicon diodes, the detectors were illuminated from the front side and from the rear side by various alpha particle sources (mainly ThC') and by monoenergetic protons with energies from 1.0 to 2.5~MeV. Their response characteristics have been studied as a function of the incoming particle energy and the applied bias voltage. The charge collection efficiency was determined as a function of fluence

  10. Theory and design of charged particle beams

    CERN Document Server

    Reiser, Martin

    1994-01-01

    Although particle accelerators are the book's main thrust, it offers a broad synoptic description of beams which applies to a wide range of other devices such as low-energy focusing and transport systems and high-power microwave sources. Develops material from first principles, basic equations and theorems in a systematic way. Assumptions and approximations are clearly indicated. Discusses underlying physics and validity of theoretical relationships, design formulas and scaling laws. Features a significant amount of recent work including image effects and the Boltzmann line charge density prof

  11. Charged particle beam current monitoring tutorial

    International Nuclear Information System (INIS)

    A tutorial presentation is made on topics related to the measurement of charged particle beam currents. The fundamental physics of electricity and magnetism pertinent to the problem is reviewed. The physics is presented with a stress on its interpretation from an electrical circuit theory point of view. The operation of devices including video pulse current transformers, direct current transformers, and gigahertz bandwidth wall current style transformers is described. Design examples are given for each of these types of devices. Sensitivity, frequency response, and physical environment are typical parameters which influence the design of these instruments in any particular application. Practical engineering considerations, potential pitfalls, and performance limitations are discussed

  12. Luminescence imaging of water during alpha particle irradiation

    Science.gov (United States)

    Yamamoto, Seiichi; Komori, Masataka; Koyama, Shuji; Toshito, Toshiyuki

    2016-05-01

    The luminescence imaging of water using the alpha particle irradiation of several MeV energy range is thought to be impossible because this alpha particle energy is far below the Cerenkov-light threshold and the secondary electrons produced in this energy range do not emit Cerenkov-light. Contrary to this consensus, we found that the luminescence imaging of water was possible with 5.5 MeV alpha particle irradiation. We placed a 2 MBq of 241Am alpha source in water, and luminescence images of the source were conducted with a high-sensitivity, cooled charge-coupled device (CCD) camera. We also carried out such imaging of the alpha source in three different conditions to compare the photon productions with that of water, in air, with a plastic scintillator, and an acrylic plate. The luminescence imaging of water was observed from 10 to 20 s acquisition, and the intensity was linearly increased with time. The intensity of the luminescence with the alpha irradiation of water was 0.05% of that with the plastic scintillator, 4% with air, and 15% with the acrylic plate. The resolution of the luminescence image of water was better than 0.25 mm FWHM. Alpha particles of 5.5 MeV energy emit luminescence in water. Although the intensity of the luminescence was smaller than that in air, it was clearly observable. The luminescence of water with alpha particles would be a new method for alpha particle detection and distribution measurements in water.

  13. Device for measuring charge density distribution in charged particle beams

    International Nuclear Information System (INIS)

    A device to measure charge density distribution in charged particle beams has been described. The device contains a set of hollow interinsulated current-receiving electrodes, recording system, and cooling system. The invention is aimed at the increase of admissible capacity of the beams measured at the expense of cooling efficiency increase. The aim is achieved by the fact, that in the device a dynamic evaporating-condensational cooling of electrodes is realized by means of cooling agent supply in perpendicular to their planes through the tubes introduced inside special cups. Spreading in radial direction over electrode surface the cooling agent gradually and intensively washes the side surface of the cup, after that, it enters the cooling cavity in the form of vapour-liquid mixture. In the cavity the cooling agent, supplied using dispensina and receiving collectors in which vapoUr is condensed, circulates. In the device suggested the surface of electrode cooling is decreased significantly at the expense of side surface of the cups which receives the electrode heat

  14. Particle Accelerator Applications: Ion and Electron Irradiation in Materials Science, Biology and Medicine

    Science.gov (United States)

    Rodríguez-Fernández, Luis

    2010-09-01

    Although the developments of particle accelerators are devoted to basic study of matter constituents, since the beginning these machines have been applied with different purposes in many areas also. Today particle accelerators are essential instruments for science and technology. This work presents an overview of the main application for direct particle irradiation with accelerator in material science, biology and medicine. They are used for material synthesis by ion implantation and charged particle irradiation; to make coatings and micromachining; to characterize broad kind of samples by ion beam analysis techniques; as mass spectrometers for atomic isotopes determination. In biomedicine the accelerators are applied for the study of effects by charged particles on cells. In medicine the radiotherapy by electron irradiation is widely used, while hadrontherapy is still under development. Also, they are necessary for short life radioisotopes production required in radiodiagnostic.

  15. Particle Accelerator Applications: Ion and Electron Irradiation in Materials Science, Biology and Medicine

    International Nuclear Information System (INIS)

    Although the developments of particle accelerators are devoted to basic study of matter constituents, since the beginning these machines have been applied with different purposes in many areas also. Today particle accelerators are essential instruments for science and technology. This work presents an overview of the main application for direct particle irradiation with accelerator in material science, biology and medicine. They are used for material synthesis by ion implantation and charged particle irradiation; to make coatings and micromachining; to characterize broad kind of samples by ion beam analysis techniques; as mass spectrometers for atomic isotopes determination. In biomedicine the accelerators are applied for the study of effects by charged particles on cells. In medicine the radiotherapy by electron irradiation is widely used, while hadrontherapy is still under development. Also, they are necessary for short life radioisotopes production required in radiodiagnostic.

  16. Surface charge accumulation of particles containing radionuclides in open air

    International Nuclear Information System (INIS)

    Radioactivity can induce charge accumulation on radioactive particles. However, electrostatic interactions caused by radioactivity are typically neglected in transport modeling of radioactive plumes because it is assumed that ionizing radiation leads to charge neutralization. The assumption that electrostatic interactions caused by radioactivity are negligible is evaluated here by examining charge accumulation and neutralization on particles containing radionuclides in open air. A charge-balance model is employed to predict charge accumulation on radioactive particles. It is shown that particles containing short-lived radionuclides can be charged with multiple elementary charges through radioactive decay. The presence of radioactive particles can significantly modify the particle charge distribution in open air and yield an asymmetric bimodal charge distribution, suggesting that strong electrostatic particle interactions may occur during short- and long-range transport of radioactive particles. Possible effects of transported radioactive particles on electrical properties of the local atmosphere are reported. The study offers insight into transport characteristics of airborne radionuclides. Results are useful in atmospheric transport modeling of radioactive plumes. - Highlights: • Radioactivity-induced charge enhances electrostatic particle interactions. • Radioactivity-induced particle charging is important in radioactivity transport. • Ionization rate coefficients of beta-emitting radionuclides are reported

  17. Mass-independent search for fractionally charged particles

    International Nuclear Information System (INIS)

    A proposed mass-independent search for fractionally charged particles with the all-electrostatic line of the IsoTRACE Laboratory at University of Toronto is described. Sensitive measurement of the fractional charge is accomplished by (1) a judicious choice of ion source and ion species, (2) charge changing and electrostatic analysis before injection into the tandem accelerator, (3) molecular destruction, charge changing, and acceleration by the tandem, (4) charge state selection and E/q analysis after acceleration, and (5) particle energy measurement with a Si surface barrier detector. In addition, the mass of the fractionally charged particles can be determined by a time of flight spectrometer. Specific cases involving +- (1/3)e and +- (2/3)e particles are discussed. Also included in the discussion are: integral charge background rejection, the procedure of the search, the signature of the fractionally charged particles, he resolutions of the analyzers and detectors, and the expected energy and time of flight spectra

  18. Test results of satellite-borne charged particle measuring instrument

    International Nuclear Information System (INIS)

    A charged particle-measuring instrument to measure on the geostationary orbit the spectra of protons, α-particles and electrons emitted from the sun was manufactured, and its performance was assured by the test on the earth. The Geostationary Meteorological Satellite, on which the instrument will be mounted, will be launched into the geostationary orbit over the pacific ocean in the summer, 1977. The instrument has five systems of detectors to cover the measuring energy range and the kinds of particles, and data are collected every several channels separately. The tests on the earth were carried out by using a cyclotron and setting the energy ranges from 1 to 15 MeV (for protons) and 6 to 30 MeV (for α-particles) through the adjustment of the accelerating conditions and absorbers of the cyclotron. The performance of the instrument was confirmed by comparing the energy and number of the irradiated charged particles measured with the instrument and the reference detector under the same conditions. The results showed that the energy-detecting characteristic was within the error range of a few percent in most cases, and the counts were within the error of 30% against the expected values. The ditinguishing characteristic of the level discriminator was also nearly equal to the estimated result, through it degrades in the vicinity of the border of channels. However, the correction of data may be required when the instrument will be really used in space, because the conditions may be somewhat different from that on the earth. (Wakatsuki, Y.)

  19. Electrophysical Systems Based On Charged Particle Accelerators

    CERN Document Server

    Vorogushin, M F

    2004-01-01

    The advancement of the charged particle accelerator engineering affects appreciably the modern tendencies of the scientific and technological progress in the world. In a number of advanced countries, this trend is one of the most dynamically progressing in the field of applied science and high-technology production. Such internationally known firms as VARIAN, SIEMENS, PHILIPS, ELECTA, IBA, HITACHI, etc., with an annual budget of milliards of dollars and growth rate of tens of percent may serve as an example. Although nowadays the projects of new large-scale accelerators for physical research are not implemented so quickly and frequently as desired, accelerating facilities are finding ever-widening application in various fields of human activities. The contribution made by Russian scientists into high-energy beams physics is generally known. High scientific and technical potential in this field, qualified personnel with a high creative potential, modern production and test facilities and state-of-the-art techn...

  20. Aberration compensation in charged particle projection lithography

    International Nuclear Information System (INIS)

    Projection systems offer the opportunity to increase the throughput for charged particle lithography, because such systems image a large area of a mask directly on to a wafer as a single shot. Shots have to be imaged over a certain range of off-axis distances at the wafer to increase the writing speed, because shot sizes are limited to about 0.25x0.25 mm2 due to aberrations. In a projection system with only lenses, however, the aberrations for off-axis shots are still very large, and some aberration compensation elements need to be introduced. In this paper, three aberration compensation elements (deflectors, stigmators and dynamic focus lenses) are first discussed, a suite of newly developed software, called PROJECTION, based on this principle and our unified aberration theory is then described, and an illustrative example computed with the software is finally given

  1. Characterisation of Medipix3 Silicon Detectors in a Charged-Particle Beam

    CERN Document Server

    Carvalho Akiba, Kazu; Aoude, Jadallah; van Beuzekom, Martinus; Buytaert, Jan; Collins, Paula; Dosil Suarez, Alvaro; Dumps, Raphael; Gallas Torreira, Abraham Antonio; Hombach, Christoph; Hynds, Daniel; John, Malcolm; Leflat, Alexander; Li, Yiming; Perez Trigo, Eliseo; Plackett, Richard; Reid, M; Rodriguez Perez, Pablo; Schindler, Heinrich; Tsopelas, Panagiotis; Vazquez Sierra, Carlos; Velthuis, Johannes; Wysokinski, Michal Adam

    2016-01-01

    While designed primarily for X-ray imaging applications, the Medipix3 ASIC can also be used for charged-particle tracking. In this work, results from a beam test at the CERN SPS with irradiated and non-irradiated sensors are presented and shown to be in agreement with simulation, demonstrating the suitability of the Medipix3 ASIC as a tool for characterising pixel sensors.

  2. Precipitation particle charge distribution and evolution of East Asian rainbands

    Science.gov (United States)

    Takahashi, Tsutomu

    2012-11-01

    Numerous videosondes, balloon-borne surveyors of precipitation particle morphology and charge, have been launched into cloud systems in many, disparate locations in East Asia. Reported here are videosonde-based observations of early summer, Baiu rainbands at Tanegashima in southern Japan and of summer rainbands at Chiang Rai in northern Thailand. Precipitation particles are mapped by type and charge over the course of cloud development, allowing particle and charge evolution to be derived. The basic charge distribution as observed in Hokuriku winter thunderclouds at different cloud life stages was seen at different locations characterized by vertical velocity profiles in the cloud. The charge structure of the rainbands in both locations was a basic tripole. The major charge carriers were graupel and ice crystals. As graupel and ice crystal concentrations increased, not only did space charge increase, but per-particle charge also increased. Increased lightning activity was associated with higher particle space charge and lower cloud-top temperature. The particle charge evolution of these systems includes several fundamental features: a. active negative charging of graupel in an intense updraft, b. descent of negative graupel along the edge of an updraft column, c. merging of negative graupel with positively charged raindrops falling in the central cloud, and d. extended distribution of positive ice crystals in the stratiform cloud. The observations suggest that riming electrification was the main charge separation mechanism.

  3. Searches for Fractionally Charged Particles: What Should Be Done Next?

    Energy Technology Data Exchange (ETDEWEB)

    Perl, Martin L.; /SLAC

    2009-01-15

    Since the initial measurements of the electron charge a century ago, experimenters have faced the persistent question as to whether elementary particles exist that have charges that are fractional multiples of the electron charge. I concisely review the results of the last 50 years of searching for fractional charge particles with no confirmed positive results. I discuss the question of whether more searching is worthwhile?

  4. Determination of colloidal particle surface charge from dielectrophoresis

    Science.gov (United States)

    Chavez, Marko; Nuansri, Rittirong; Mazza, Jacob; Ou-Yang, H. Daniel

    2015-03-01

    Electrophoresis (EP) is used to determine colloidal particle surface charge. However, when the Debye length is comparable to or larger than the particle size, electrophoresis cannot be reliably used to determine the surface charge due to counter ion retardation flow. Alexander et al. developed a theory relating colloidal osmotic pressure and particle surface charge. We use dielectrophoresis (DEP) to obtain a potential landscape based on the number density distribution of the particles in a non-uniform AC electric field. We determine the osmotic pressure from the DEP force and density profiles using Einstein's osmotic equilibrium equation. Surface charge obtained by DEP (thermodynamics) will be compared to that obtained by EP (electrokinetics).

  5. Bibliography of integral charged particle nuclear data. Archival edition

    International Nuclear Information System (INIS)

    This is the fourth annual edition of the National Nuclear Data Center charged-particle bibliography. This edition is cumulative and supersedes the previous editions. The bibliography's primary aims are to satisfy the need for a concise and comprehensive index of integral charged-particle cross section data and to provide an index of charged-particle data compiled in the international exchange format. References in this Part are by target for the various incident charged particles (in order of increasing A). The present publication is an archival volume; future publications will be cumulative supplements to this edition

  6. Spatiotemporal kinetics of γ-H2AX protein on charged particles induced DNA damage

    Science.gov (United States)

    Niu, H.; Chang, H. C.; Cho, I. C.; Chen, C. H.; Liu, C. S.; Chou, W. T.

    2014-08-01

    In several researches, it has been demonstrated that charged particles can induce more complex DNA damages. These complex damages have higher ability to cause the cell death or cell carcinogenesis. For this reason, clarifying the DNA repair mechanism after charged particle irradiation plays an important role in the development of charged particle therapy and space exploration. Unfortunately, the detail spatiotemporal kinetic of DNA damage repair is still unclear. In this study, we used γ-H2AX protein to investigate the spatiotemporal kinetics of DNA double strand breaks in alpha-particle irradiated HeLa cells. The result shows that the intensity of γ-H2AX foci increased gradually, and reached to its maximum at 30 min after irradiation. A good linear relationship can be observed between foci intensity and radiation dose. After 30 min, the γ-H2AX foci intensity was decreased with time passed, but remained a large portion (∼50%) at 48 h passed. The data show that the dissolution rate of γ-H2AX foci agreed with two components DNA repairing model. These results suggest that charged particles can induce more complex DNA damages and causing the retardation of DNA repair.

  7. Evidence for plasma effect on charge collection efficiency in proton irradiated GaAs detectors

    CERN Document Server

    Nava, F; Canali, C; Vittone, E; Polesello, P; Biggeri, U; Leroy, C

    1999-01-01

    The radiation damage in 100 mu m thick Schottky diodes made on semi-insulating undoped GaAs materials, were studied using alpha-, beta-, proton- and gamma-spectroscopy as well as I-V measurements. The results have been analysed within the framework of the Hecht model to investigate the influence of the plasma produced by short-range strongly ionising particles on the detector performance after 24 GeV proton irradiation. It has been found that with the mean free drift lengths for electrons and holes determined from alpha-spectra in overdepleted detectors, the charge collection efficiency for beta-particles, cce subbeta, is well predicted in the unirradiated detectors, while in the most irradiated ones, the cce subbeta is underestimated by more than 40%. The observed disagreement can be explained by assuming that the charge carrier recombination in the plasma region of such detectors, becomes significant.

  8. Preparation for Irradiation Testing of Coated Particle Fuel at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Goo; Park, Sung Jae; Hong, Sung Taek; Lee, Byung Chul; Jeong, Kyungchai; Kim, Yeonku; Kim, Woong Ki; Lee, Young Woo; Cho, Moon Sung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    The first irradiation testing of TRISO-coated particle fuel will be carried out in HANARO. The irradiation device, which contains two separate test rods, was designed for considering the irradiation position location and size, irradiation parameters (e. g. power, temperature, fluence, etc.), and manufactured. This device will be loaded and irradiated in the OR5 test hole in the HANARO core from the middle of this year. The irradiation device including two test rods was successfully fabricated, and will be loaded and irradiated in the test hole, OR5, of the HANARO core from the middle of this year. In 2012, the detailed design of an irradiation device for irradiation testing of TRISO (tri-structural isotropic)-coated particle fuel at HANARO (High-flux Advanced Neutron Application Reactor) was accepted, and the device was fabricated except the test fuel rods.

  9. VEDs for charged particle accelerators: Indian scenario

    International Nuclear Information System (INIS)

    In the initial times after their invention, the charged particle accelerators have, primarily, been used for fundamental studies on nuclei and atoms. From the first modern accelerator, the cathode ray tube, used by J.J. Thomson for the discovery of electron, very recently the gigantic 27 km circumference Large Hadron Collider (LHC) is operational in the search of Higg's boson and related physics issues. Particle accelerators have emerged as powerful microscopes for investigating the finest details of cells, genes, molecules, atoms, protons, neutrons, muons, electrons, quarks and, possibly, still undiscovered even more fundamental constituents of the universe, such as dark matter and dark energy. Several noble prize winning discoveries have been made using accelerators. Accelerators are now being used in a wide area of industrial and medical applications. They are used for the production of radioisotopes for medical imaging, cancer therapy, food sterilization, treatment of waste water, sterilization of medical equipment, material modification, mass spectroscopy, cargo scanning, fabrication of semiconductors etc. Ongoing effort towards the development of accelerators with megawatt beam power is showing hope for a cleaner source of nuclear energy and treatment of nuclear waste. Several tens of thousands of accelerators are presently operational in the world for basic research and applications. Development of new accelerators has several times been driven by new technologies and materials and sometimes they have driven the technological developments towards cutting edge. Some examples are ultra-high vacuum in large volumes, superfluid helium in cryogenics, cryocoolers, superconducting magnets and RF cavities, high power vacuum electronic devices, global control systems, superfast computing and communication networks, giant data storage/processing systems etc. India has been pursuing a fairly robust programme of accelerator development at various institutions. It

  10. Charge collection efficiency studies with irradiated silicon detectors

    CERN Document Server

    Allport, P P; Casse, G; Greenall, A; Jackson, J N; Turner, P R

    2003-01-01

    Small area (1x1 cm sup 2) microstrip detectors, made with a p sup + -n diode structure on FZ silicon substrates, both with and without oxygen enrichment, have been irradiated with 24 GeV/c protons to fluences of 1.9, 2.9 and 5.1x10 sup 1 sup 4 p/cm sup 2. Their charge collection properties have been studied using a sup 1 sup 0 sup 6 Ru beta-source with a wide bandwidth current amplifier and compared with those for a non-irradiated device. The integrated charge collected at different times (10, 25, 40 and 80 ns) has been used to estimate the effect of ballistic deficit. Predictions for the reduction in charge collection efficiency expected at fluences as high as 10 sup 1 sup 5 cm sup - sup 2 are presented using a parameterization described in earlier work which also fits this data well.

  11. The effect of single-particle charge limits on charge distributions in dusty plasmas

    International Nuclear Information System (INIS)

    An analytical expression for the stationary particle charge distribution in dusty plasmas is derived that accounts for the existence of single-particle charge limits. This expression is validated by comparison with the results of Monte Carlo charging simulations. The relative importance of the existence of charge limits for various values of the ratio of electron-to-ion density and ion mass is examined, and the effect of charge limits on the transient behavior of the charge distribution is considered. It is found that the time required to reach a steady-state charge distribution strongly decreases as the charge limit decreases, and that the existence of charge limits causes high-frequency charge fluctuations to become relatively more important than in the case without charge limits. (paper)

  12. A novel silicon array designed for intraoperative charged particle imaging

    International Nuclear Information System (INIS)

    A novel Si-PIN imaging array is under investigation for a charged particle (beta, positron, or alpha) sensitive intraoperative camera to be used for (residual) tumor identification during surgery. This class of collimator-less nuclear imaging device has a higher signal response for direct interactions than its scintillator-optical detector-based counterparts. Monte Carlo simulations with 635 keV betas were performed, yielding maximum and projected ranges of 1.64 and 0.55 mm in Si. Up to 90% of these betas were completely absorbed in the first 0.30 mm. Based on these results, 300 μm thick prototype Si detector arrays were designed in a 16x16 crossed-grid arrangement with 0.8 mm wide orthogonal strips on 1.0 mm pitch. A NIM- and CAMAC-based high-density data acquisition and processing system was used to collect the list mode data. The system was calibrated by comparisons of measured spectra to energy deposition simulations or by direct measurement of various >100 keV conversion electron or beta emitters. Mean electronic noise per strip was 2 pixel size, and measurements of beta emitting point and line sources yielded FWHM resolutions of 1.5 (lateral) and 2.5 mm (diagonal), respectively, with the larger widths due to particle range blurring effects. Deconvolution of the finite source size yielded intrinsic resolutions that corresponded to the image pixel size. Transmission images of circle and line phantoms with various hole sizes and pitch were resolved with either pure beta or positron irradiation without a background correction. This novel semiconductor imaging device facilitates high charged particle and low gamma sensitivity, high signal/noise ratio, and allows for compact design to potentially aid surgical guidance by providing in situ images of clinical relevance

  13. Effects of charged particles on DNA

    International Nuclear Information System (INIS)

    It can be noted that it is not simple double strand breaks (dsb) but the non-reparable breaks that are associated with high biological effectiveness in the cell killing effect for high LET radiation. Here, we have examined the effectiveness of fast neutrons and low (initial energy = 12 MeV/u) or high (135 MeV/u) energy charged particles on cell death in 19 mammalian cell lines including radiosensitive mutants. Some of the radiosensitive lines were deficient in DNA dsb repair such as LX830, M10, V3, and L5178Y-S cells and showed lower values of relative biological effectiveness (RBE) for fast neutrons if compared with their parent cell lines. The other lines of human ataxia-telangiectasia fibroblasts, irs 1, irs 2, irs 3 and irs 1SF cells, which were also radiosensitive but known as proficient in dsb repair, showed moderate RBEs. Dsb repair deficient mutants showed low RBE values for heavy ions. These experimental findings suggest that the DNA repair system does not play a major role against the attack of high linear energy transfer (LET) radiations. Therefore, we hypothesize that a main cause of cell death induced by high LET radiations is due to non-reparable dsb, which are produced at a higher rate compared to low LET radiations. (author)

  14. Charged-particle beam: a safety mandate

    International Nuclear Information System (INIS)

    The Advanced Test Accelerator (ATA) is a recent development in the field of charged particle beam research at Lawrence Livermore National Laboratory. With this experimental apparatus, researchers will characterize intense pulses of electron beams propagated through air. Inherent with the ATA concept was the potential for exposure to hazards, such as high radiation levels and hostile breathing atmospheres. The need for a comprehensive safety program was mandated; a formal system safety program was implemented during the project's conceptual phase. A project staff position was created for a safety analyst who would act as a liaison between the project staff and the safety department. Additionally, the safety analyst would be responsible for compiling various hazards analyses reports, which formed the basis of th project's Safety Analysis Report. Recommendations for safety features from the hazards analysis reports were incorporated as necessary at appropriate phases in project development rather than adding features afterwards. The safety program established for the ATA project faciliated in controlling losses and in achieving a low-level of acceptable risk

  15. Comprehensive study of the effects of irradiation on charge collection efficiency in silicon detectors

    CERN Document Server

    Borello, L; Dutta, S; Gennai, Simone; Mariani, M; Messineo, A; Segneri, G; Starodumov, Andrei; Teodorescu, L; Tonelli, G; Verdini, P G

    2001-01-01

    The charge collection efficiency (CCE) for heavily irradiated silicon devices has been carefully investigated on a series of microstrip detectors. Large-area sensors designed for the CMS silicon tracker have been irradiated with neutrons and protons up to a very high fluence. Effects on CCE have been studied using a beam of minimum ionizing particles and a fast shaping time electronics similar to what is expected in CMS. The paper shows the performance of the sensors for CCE and signal-to-noise ratio under different operating conditions. (10 refs).

  16. Charge collection and space charge distribution in neutron-irradiated epitaxial silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Poehlsen, Thomas

    2010-04-15

    In this work epitaxial n-type silicon diodes with a thickness of 100 {mu}m and 150 {mu}m are investigated. After neutron irradiation with fluences between 10{sup 14} cm{sup -2} and 4 x 10{sup 15} cm{sup -2} annealing studies were performed. CV-IV curves were taken and the depletion voltage was determined for different annealing times. All investigated diodes with neutron fluences greater than 2 x 10{sup 14} cm{sup -2} showed type inversion due to irradiation. Measurements with the transient current technique (TCT) using a pulsed laser were performed to investigate charge collection effects for temperatures of -40 C, -10 C and 20 C. The charge correction method was used to determine the effective trapping time {tau}{sub eff}. Inconsistencies of the results could be explained by assuming field dependent trapping times. A simulation of charge collection could be used to determine the field dependent trapping time {tau}{sub eff}(E) and the space charge distribution in the detector bulk. Assuming a linear field dependence of the trapping times and a linear space charge distribution the data could be described. Indications of charge multiplication were seen in the irradiated 100 {mu}m thick diodes for all investigated fluences at voltages above 800 V. The space charge distribution extracted from TCT measurements was compared to the results of the CV measurements and showed good agreement. (orig.)

  17. Charge collection and space charge distribution in neutron-irradiated epitaxial silicon detectors

    International Nuclear Information System (INIS)

    In this work epitaxial n-type silicon diodes with a thickness of 100 μm and 150 μm are investigated. After neutron irradiation with fluences between 1014 cm-2 and 4 x 1015 cm-2 annealing studies were performed. CV-IV curves were taken and the depletion voltage was determined for different annealing times. All investigated diodes with neutron fluences greater than 2 x 1014 cm-2 showed type inversion due to irradiation. Measurements with the transient current technique (TCT) using a pulsed laser were performed to investigate charge collection effects for temperatures of -40 C, -10 C and 20 C. The charge correction method was used to determine the effective trapping time τeff. Inconsistencies of the results could be explained by assuming field dependent trapping times. A simulation of charge collection could be used to determine the field dependent trapping time τeff(E) and the space charge distribution in the detector bulk. Assuming a linear field dependence of the trapping times and a linear space charge distribution the data could be described. Indications of charge multiplication were seen in the irradiated 100 μm thick diodes for all investigated fluences at voltages above 800 V. The space charge distribution extracted from TCT measurements was compared to the results of the CV measurements and showed good agreement. (orig.)

  18. Particles and scalar waves in noncommutative charged black hole spacetime

    OpenAIRE

    Bhar, Piyali; Rahaman, Farook; Biswas, Ritabrata(Indian Institute of Engineering Sceince and Technology Shibpur (Formerly, Bengal Engineering and Science University Shibpur), 711 013, Howrah, West Bengal, India); Mondal, U. F.

    2015-01-01

    In this paper we have discussed geodesics and the motion of test particle in the gravitational field of noncommutative charged black hole spacetime. The motion of massive and massless particle have been discussed seperately. A comparative study of noncommutative charged black hole and usual Reissner-Nordstrom black hole has been done. The study of effective potential has also been included. Finally, we have examined the scattering of scalar waves in noncommutative charged black hole spacetime.

  19. Particles and Scalar Waves in Noncommutative Charged Black Hole Spacetime

    Science.gov (United States)

    Piyali, Bhar; Farook, Rahaman; Ritabrata, Biswas; U. F., Mondal

    2015-07-01

    In this paper we have discussed geodesics and the motion of test particle in the gravitational field of non-commutative charged black hole spacetime. The motion of massive and massless particle have been discussed seperately. A comparative study of noncommutative charged black hole and usual Reissner-Nordström black hole has been done. The study of effective potential has also been included. Finally, we have examined the scattering of scalar waves in noncommutative charged black hole spacetime.

  20. Dynamics of fast charged particle beam rotation in bended crystals

    International Nuclear Information System (INIS)

    Dynamics of fast charged particle beam rotation in a bended monocrystal is considered. Face and volume mechanisms of capture in channels are taken into account simultaneously in the model presented. Functions of distribution in transverse energies (φ) of channeled and dechanneled particles are obtained. Charge-energy ''scale invariance'' in ion channeling with charge Z in a bended crystal determined by scale parameter W=pv/Z (p and v are pulse and velocity local to transverse planes) follows from the model presented

  1. Spatiotemporal kinetics of γ-H2AX protein on charged particles induced DNA damage

    Energy Technology Data Exchange (ETDEWEB)

    Niu, H., E-mail: hniu@mx.nthu.edu.tw [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu, Taiwan (China); Chang, H.C. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan (China); Cho, I.C. [Institute for Radiological Research, Chang Gung University and Chang Gung Memorial Hospital, Taoyuan, Taiwan (China); Chen, C.H. [Nuclear Science and Technology Development Center, National Tsing Hua University, Hsinchu, Taiwan (China); Liu, C.S. [Cancer Center of Taipei Veterans General Hospital, Taipei, Taiwan (China); Chou, W.T. [Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu, Taiwan (China)

    2014-08-15

    Highlights: • Charged particles can induce more complex DNA damages, and these complex damages have higher ability to cause the cell death or cell carcinogenesis. • In this study, we used γ-H2AX protein to investigate the spatiotemporal kinetics of DNA double strand breaks in particle irradiated HeLa cells. • The HeLa cells were irradiated by 400 keV alpha-particles in four different dosages. • The result shows that a good linear relationship can be observed between foci number and radiation dose. • The data shows that the dissolution rate of γ-H2AX foci agree with the two components DNA repairing model, and it was decreasing as the radiation dose increased. • These results suggest that charged particles can induce more complex DNA damages and causing the retardation of DNA repair. - Abstract: In several researches, it has been demonstrated that charged particles can induce more complex DNA damages. These complex damages have higher ability to cause the cell death or cell carcinogenesis. For this reason, clarifying the DNA repair mechanism after charged particle irradiation plays an important role in the development of charged particle therapy and space exploration. Unfortunately, the detail spatiotemporal kinetic of DNA damage repair is still unclear. In this study, we used γ-H2AX protein to investigate the spatiotemporal kinetics of DNA double strand breaks in alpha-particle irradiated HeLa cells. The result shows that the intensity of γ-H2AX foci increased gradually, and reached to its maximum at 30 min after irradiation. A good linear relationship can be observed between foci intensity and radiation dose. After 30 min, the γ-H2AX foci intensity was decreased with time passed, but remained a large portion (∼50%) at 48 h passed. The data show that the dissolution rate of γ-H2AX foci agreed with two components DNA repairing model. These results suggest that charged particles can induce more complex DNA damages and causing the retardation of DNA

  2. Charged particle periodicity in the Saturnian magnetosphere

    International Nuclear Information System (INIS)

    The low energy charged particles (LECP) experiments on the Voyager 1 and 2 spacecraft performed measurements of electrons (approx.22 keV to approx.20 MeV) and ions (approx.28 keV to approx.150 MeV) during the Saturn encounters in 1980 and 1981. Count rate ratios of two of the low energy electron (22 to 35 keV and 183 to 500 keV) and ion (43 to 80 keV and 137 to 215 keV) channels exhibit an approximation 10 hour periodicity in the outer Saturnian magnetosphere beyond the orbit of Titan. Electron ratios vary from approx.50 to approx.300; ion ratios vary from approx.3 to approx.20. Similar but less pronounced periodicities are observed for higher and lower energy electron and ion spectral indices. Three complete cycles were observed during the Voyager 2 outbound portion of the encounter from which were determined an electron ratio period of 10/sup h/21/sup m/ +- 48/sup m/ and an ion ratio period of 9/sup h/49/sup m/ +- 59/sup m/. Using Saturn Kilometric Radiation (SKR) and Saturn Electrostatic Discharge (SED) periods, extrapolation backward from Voyager 2 to Voyager 1 suggests that the periodicities are Saturnian rather than Jovian in nature, and that they persist in phase for time intervals at least as long as 287 days. Ratio minima, or spectral hardenings, occur in the same hemisphere as do auroral brightenings, SKR activity, and spoke enhanement. We interpret the observations as prima facie evidence of an asymmetry in the Saturian magnetic field and the root cause of the observed SKR periodicity

  3. Photon production by charged particles in narrow optical fibers

    OpenAIRE

    Artru, X.; Ray, C.

    2006-01-01

    Presented at International Conference on Charged and Neutral Particles Channeling Phenomena, Frascati, Italy, July 3-7, 2006. - Theorie, CAS A charged particle passing through or by an optical fiber induces emission of light guided by the fiber. The formula giving the spontaneous emission amplitude are given in the general case when the particle trajectory is not parallel to the fiber axis. At small angle, the photon yield grows like the inverse power of the angle and in the parallel limit...

  4. Massive Vector Particles Tunneling From Noncommutative Charged Black Holes

    CERN Document Server

    Övgün, Ali

    2015-01-01

    In this paper, we investigate the tunneling process of charged massive bosons $W^{\\pm}$ (spin-1 particles) from noncommutative charged black holes such as charged RN black holes and charged BTZ black holes. By applying the WKB approximation and by using the Hamilton-Jacobi equation we derive the tunneling rate and the corresponding Hawking temperature for those black holes configuration. The tunneling rate shows that the radiation deviates from pure thermality and is consistent with an underlying unitary theory.

  5. Charge collection and charge pulse formation in highly irradiated silicon planar detectors

    Energy Technology Data Exchange (ETDEWEB)

    Dezillie, B.; Li, Z. [Brookhaven National Lab., Upton, NY (United States); Eremin, V. [Academy of Science of Russia, St. Petersburg (Russian Federation). A.F. Ioffe Physico-Technical Inst.

    1998-06-01

    The interpretation of experimental data and predictions for future experiments for high-energy physics have been based on conventional methods like capacitance versus voltage (C-V) measurements. Experiments carried out on highly irradiated detectors show that the kinetics of the charge collection and the dependence of the charge pulse amplitude on the applied bias are deviated too far from those predicted by the conventional methods. The described results show that in highly irradiated detectors, at a bias lower than the real full depletion voltage (V{sub fd}), the kinetics of the charge collection (Q) contains a fast and a slow component. At V = V{sub fd}*, which is the full depletion voltage traditionally determined by the extrapolation of the fast comopnent amplitude of q versus bias to the maximum value or from the standard C-V measurements, the pulse has a slow component with significant amplitude. This slow component can only be eliminated by applying additional bias that amounts to the real full depletion voltage (V{sub fd}) or more. The above mentioned regularities are explained in this paper in terms of a model of an irradiated detector with multiple regions. This model allows one to use C-V, in a modified way, as well as TChT (transient charge technique) measurements to determine the V{sub fd} for highly irradiated detectors.

  6. Charge carrier rearrangement in spinel crystals irradiated at low temperatures

    International Nuclear Information System (INIS)

    The results of an investigation of thermoluminescence (TL) in nominally pure MgAl2O4 spinel single crystals in the temperature range between 80-670 K are presented. For a heating rate of 0.21 K/s, TL spectra exhibit glow peaks in three distinct temperature ranges: 100-160, 270-370 and 470-670 K. The most prominent peaks are at 115, 140, 305, 335, 525, 570 and 605 K. The locations of the temperature maxima, as well as the intensity of the peaks, vary depending on the treatment of the crystals, the type of irradiation and the temperature of irradiation. Measurements of the glow peaks at different emission wavelengths and the use of partial bleaching and isothermal decay techniques for TL, allowed us to propose mechanisms for charge carrier rearrangement at lattice defects and impurity ions, during irradiation and subsequent heating

  7. Irradiation Device for Irradiation Testing of Coated Particle Fuel at HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Goo; Park, Sung Jae; Hong, Sung Taek; Lee, Byung Chul; Jeong, Kyungchai; Kim, Yeonku; Kim, Woongki; Lee, Youngwoo; Cho, Moon Sung; Kim, Yong Wan [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-12-15

    The Korean Nuclear-Hydrogen Technology Development (NHTD) Plan will be performing irradiation testing of coated particle fuel at HANARO to support the development of VHTR in Korea. This testing will be carried out to demonstrate and qualify TRISO-coated particle fuel for use in VHTR. The testing will be irradiated in an inert gas atmosphere without on-line temperature monitoring and control combined with on-line fission product monitoring of the sweep gas. The irradiation device contains two test rods, one has nine fuel compacts and the other five compacts and eight graphite specimens. Each compact contains about 260 TRISO-coated particles. The irradiation device is being loaded and irradiated into the OR5 hole of the in HANARO core from August 2013. The device will be operated for about 150 effective full-power days at a peak temperature of about 1030 .deg. C in BOC (Beginning of Cycle) during irradiation testing. After a peak burn-up of about 4 atomic percentage and a peak fast neutron fluence of about 1.7 Χ 10{sup 21} n/cm{sup 2}, PIE (Post-Irradiation Examination) of the irradiated coated particle fuel will be performed at IMEF (Irradiated Material Examination Facility). This paper reviews the design of test rod and irradiation device for coated particle fuel, and discusses the technical results for irradiation testing at HANARO.

  8. Highly charged hollow latex particles prepared via seeded emulsion polymerization.

    Science.gov (United States)

    Nuasaen, Sukanya; Tangboriboonrat, Pramuan

    2013-04-15

    The carboxylated hollow latex (HL) particles possessing high surface charge density were conveniently prepared by using poly(styrene-co-acrylic acid) (P(St/AA)) as seed particles and methyl methacrylate (MMA)/divinylbenzene (DVB)/AA as monomers. Without seed removal, the hollow structure was simply tuned by adjusting the monomer/seed ratio and the monomer content. The monodisperse, spherical, and non-collapsed HL particles with double shell having the void of 280 nm were obtained from P(St/AA) seeds of 300 nm. The conductimetric back titration, SEM, TEM, and dynamic light scattering measurement revealed that the surface charge density, surface roughness, and size of HL particles significantly increased when applying the stepwise charging monomers/initiator. The highly charged HL particles would be well dispersed in coating film providing good optical properties, for example, opacity and whiteness. PMID:23428072

  9. Anomalous mobility of highly charged particles in pores.

    Science.gov (United States)

    Qiu, Yinghua; Yang, Crystal; Hinkle, Preston; Vlassiouk, Ivan V; Siwy, Zuzanna S

    2015-08-18

    Single micropores in resistive-pulse technique were used to understand a complex dependence of particle mobility on its surface charge density. We show that the mobility of highly charged carboxylated particles decreases with the increase of the solution pH due to an interplay of three effects: (i) ion condensation, (ii) formation of an asymmetric electrical double layer around the particle, and (iii) electroosmotic flow induced by the charges on the pore walls and the particle surfaces. The results are important for applying resistive-pulse technique to determine surface charge density and zeta potential of the particles. The experiments also indicate the presence of condensed ions, which contribute to the measured current if a sufficiently high electric field is applied across the pore. PMID:26177843

  10. Bibliography of integral charged particle nuclear data. Archival edition

    International Nuclear Information System (INIS)

    This is the fourth annual edition of the National Nuclear Data Center charged-particle bibliography. This edition is cumulative and supersedes the previous editions. The bibliography's primary aims are to satisfy the need for a concise and comprehensive index of integral charged-particle cross section data and to provide an index of charged-particle data compiled in the international exchange format, EXFOR. This part of the publication deals with isotope production; references are ordered by mass of the nuclide produced. The present publication is an archival volume; future publications will be cumulative supplements to this edition

  11. Quantum interface to charged particles in a vacuum

    Science.gov (United States)

    Okamoto, Hiroshi

    2015-11-01

    A superconducting qubit device suitable for interacting with a flying electron has recently been proposed [Okamoto and Nagatani, Appl. Phys. Lett. 104, 062604 (2014), 10.1063/1.4865244]. Either a clockwise or counterclockwise directed loop of half magnetic flux quantum encodes a qubit, which naturally interacts with any single charged particle with arbitrary kinetic energy. Here, the device's properties, sources of errors, and possible applications are studied in detail. In particular, applications include detection of a charged particle essentially without applying a classical force to it. Furthermore, quantum states can be transferred between an array of the proposed devices and the charged particle.

  12. Heavy-ion radiography applied to charged particle radiotherapy

    International Nuclear Information System (INIS)

    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

  13. Irradiation performance of thorium oxide based coated particle fuels

    International Nuclear Information System (INIS)

    BISO coated ThO2 particles as fertile fuel and BISO or TRISO coated (Th, U)O2 particles as fissile fuel for a High-temperature Gas-cooled Reactor (HTGR) were irradiated to investigate particle performances in loosely-packed condition of two capsules in JRR-2 and one capsule in JMTR. Irradiation of these coated particles was achieved to a maximum fast neutron fluence of 2.22 x 1021 neutrons/cm2 (E > 0.18 MeV) and a maximum thermal neutron fluence of 1.35 x 1021 neutrons/cm2 at temperatures of 770 to 1225 deg C. And a maximum burnup of fissile particles was 2.42 % FIMA. It was found in the post-irradiation examinations that the coated particles were intact except a little of the BISO coated fissile particles, and the thorium oxide based coated particles performed well under the irradiation conditions. The data were also taken on the fission product behavior released from the fuel kernels during the irradiation. And density of the outer LTIPyC (OPyC) increased as increasing the fluence of fast neutron. As a result of the densification of the OPyC, the crushing strength of the BISO coated particles increased, otherwise the TRISO coated particles decreased. (author)

  14. Basic study for a novel combined treatment with a nano-DDS and charged particle therapy

    International Nuclear Information System (INIS)

    To realize a novel cancer therapy, ''Nano-Drug Delivery System (Nano-DDS)-Charged Particle Therapy'', we performed a basic study using multimodal thermo-sensitive polymer-modified liposomes (MTPLs) containing a MR contrast agent, fluorescence dye and anticancer drug. In our previous work, Nano-DDS thermal therapy using the MTPLs was performed for pre-clinical research. The MTPL accumulated in the subcutaneous tumors for over 8 hours after administration, and the temperature-triggered membrane disruption was visualized as a signal enhancement in T1-weighted MRI. The effects of treatment using MTPL with heating were found to increase. The purpose of this year's research was to assess the treatment effects using MTPLs with heating and charged particle therapy, and to evaluate MR signal changes after irradiation with charged particles. (author)

  15. Charged particle equilibrium effects on the electron absorbed fraction in the extra-thoracic airways

    International Nuclear Information System (INIS)

    Estimates of the dose to the extra thoracic airway (nasal vestibule) from inhaled beta-emitting radionuclides, obtained using the respiratory tract model presented in Publication 66 of the International Commission on Radiological Protection, frequently predict that the basal cells in this region are the most highly irradiated tissues of the body. The dose to the basal cells is averaged over a layer of tissue 10 μm thick located at a depth of 40 μm into the airway assuming that charged particle equilibrium exists. Since the target (basal cell layer) is very small and thin (10 cm2 area and 10 μm thickness), charged particle equilibrium does not exist. In this work the effect on the absorbed fraction of the lack of charged particle equilibrium is investigated. (authors)

  16. Mechanisms of Particle Charging by Surfactants in Nonpolar Dispersions.

    Science.gov (United States)

    Lee, Joohyung; Zhou, Zhang-Lin; Alas, Guillermo; Behrens, Sven Holger

    2015-11-10

    Electric charging of colloidal particles in nonpolar solvents plays a crucial role for many industrial applications and products, including rubbers, engine oils, toners, or electronic displays. Although disfavored by the low solvent permittivity, particle charging can be induced by added surfactants, even nonionic ones, but the underlying mechanism is poorly understood, and neither the magnitude nor the sign of charge can generally be predicted from the particle and surfactant properties. The conclusiveness of scientific studies has been limited partly by a traditional focus on few surfactant types with many differences in their chemical structure and often poorly defined composition. Here we investigate the surface charging of poly(methyl methacrylate) particles dispersed in hexane-based solutions of three purified polyisobutylene succinimide polyamine surfactants with "subtle" structural variations. We precisely vary the surfactant chemistry by replacing only a single electronegative atom located at a fixed position within the polar headgroup. Electrophoresis reveals that these small differences between the surfactants lead to qualitatively different particle charging. In the respective particle-free surfactant solutions we also find potentially telling differences in the size of the surfactant aggregates (inverse micelles), the residual water content, and the electric solution conductivity as well as indications for a significant size difference between oppositely charged inverse micelles of the most hygroscopic surfactant. An analysis that accounts for the acid/base properties of all constituents suggests that the observed particle charging is better described by asymmetric adsorption of charged inverse micelles from the liquid bulk than by charge creation at the particle surface. Intramicellar acid-base interaction and intermicellar surfactant exchange help rationalize the formation of micellar ions pairs with size asymmetry. PMID:26484617

  17. Charge collection efficiency recovery in heavily irradiated silicon detectors operated at cryogenic temperatures

    CERN Document Server

    Da Vià, C; Berglund, P; Borchi, E; Borer, K; Bruzzi, Mara; Buontempo, S; Casagrande, L; Chapuy, S; Cindro, V; Dimcovski, Zlatomir; D'Ambrosio, N; de Boer, Wim; Dezillie, B; Esposito, A P; Granat, V; Grigoriev, E; Heijne, Erik H M; Heising, S; Janos, S; Koivuniemi, J H; Konotov, I; Li, Z; Lourenço, C; Mikuz, M; Niinikoski, T O; Pagano, S; Palmieri, V G; Paul, S; Pirollo, S; Pretzl, Klaus P; Ropotar, I; Ruggiero, G; Salmi, J; Seppä, H; Suni, I; Smith, K; Sonderegger, P; Valtonen, M J; Zavrtanik, M

    1998-01-01

    The charge collection efficiency (CCE) of high resistivity silicon detectors, previously neutron irradiated up to 2*10/sup 15/ n/cm/sup 2/, was measured at different cryogenic temperatures and different bias voltages. In order to $9 study reverse annealing (RA) effects, a few samples were heated to 80 degrees C and kept at room temperature for several months after irradiation. For comparison other samples (NRA) where kept at -10 C after irradiation. The RA and $9 NRA samples, measured at 250 V forward and reverse bias voltage, present a common temperature threshold at 150 K. Below 120 K the CCE is constant and ranges between 55and 65 0.000000or the RA and NRA sample respectively. Similar CCE $9 was measured for a device processed with low resistivity contacts (OHMIC), opening the prospect for a consistent reduction of the cost of large area particle tracking. (7 refs).

  18. Charged particle interaction with a chirped electromagnetic pulse

    OpenAIRE

    Khachatryan, A. G.; Boller, K. -J.; Goor, van, Fred

    2003-01-01

    It is found that a charged particle can get a net energy gain from the interaction with an electromagnetic chirped pulse. Theoretically, the energy gain increases with the pulse amplitude and with the relative frequency variation in the pulse.

  19. Charged particle beam scanning using deformed high gradient insulator

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu -Jiuan

    2015-10-06

    Devices and methods are provided to allow rapid deflection of a charged particle beam. The disclosed devices can, for example, be used as part of a hadron therapy system to allow scanning of a target area within a patient's body. The disclosed charged particle beam deflectors include a dielectric wall accelerator (DWA) with a hollow center and a dielectric wall that is substantially parallel to a z-axis that runs through the hollow center. The dielectric wall includes one or more deformed high gradient insulators (HGIs) that are configured to produce an electric field with an component in a direction perpendicular to the z-axis. A control component is also provided to establish the electric field component in the direction perpendicular to the z-axis and to control deflection of a charged particle beam in the direction perpendicular to the z-axis as the charged particle beam travels through the hollow center of the DWA.

  20. Techniques used for charged particle nuclear data evaluation at CNDC

    International Nuclear Information System (INIS)

    The methods and techniques used for Charged Particle Nuclear Data (CPND) evaluation at Chinese Nuclear Data Center (CNDC) are summarized, including compilation and evaluation of experimental data, nuclear reaction theory and model calculation, systematics research and comprehensive recommendation etc

  1. Silicon pin diode array hybrids for charged particle detection

    International Nuclear Information System (INIS)

    This paper reports on the design of silicon PIN diode array hybrids for use as charged particle detectors. A brief summary of the need for vertex detectors is presented. Circuitry, block diagrams and device specifications are included

  2. Radiobiology with heavy charged particles: a historical review

    Energy Technology Data Exchange (ETDEWEB)

    Skarsgard, L.D. [Dept. of Medical Biophysics, B.C. Cancer Research Centre and TRIUMF, Vancouver (Canada)

    1997-09-01

    The presentation will attempt to briefly review some of radiobiological data on the effects of heavy charged particles and to discuss the influence of those studies on the clinical application which followed. (orig./MG)

  3. Deposition of Aerosol Particles in Electrically Charged Membrane Filters

    International Nuclear Information System (INIS)

    A theory for the influence of electric charge on particle deposition on the surface of charged filters has been developed. It has been tested experimentally on ordinary membrane filters and Nuclepore filters of 8 μm pore size, with a bipolar monodisperse test aerosol of 1 μm particle diameter, and at a filter charge up to 20 μC/m2. Agreement with theory was obtained for the Coulomb force between filter and particle for both kinds of filters. The image force between charged filter and neutral particles did not result in the predicted deposition in the ordinary membrane filter, probably due to lacking correspondence between the filter model employed for the theory, and the real filter. For the Nuclepore filter a satisfactory agreement with theory was obtained, also at image interaction

  4. On the charged particle shock acceleration

    International Nuclear Information System (INIS)

    The shock acceleration method employs injection of beam particles into the linear accelerator unexcited structure. Upon injecting a wave of accelerating electromagnetic field is excited in the structure it catches up with the particles and accelerates them. Dynamics of particle acceleration using the abovesaid method is under consideration. A d gree of particle beam compression in the process of beam acceleration is found out. New technique is suggested of shock acceleration with particle outlet to the potential barrier plateau that enables to attain compression not only of relativistic beams but also of non relativistic ones. It is shown that the method in question enables to get compression of electron and ion beams while increasing essentially their current and reducing the density modulation period. Shock acceleration in high current accelerators enables to obtain high-energy current beams (above 104A), which ght be used in studies on ionic thermonuclear fusion in powerful free electron lasers

  5. Limits on the production of massive stable charged particles

    International Nuclear Information System (INIS)

    We present improved limits on the production of massive stable charged particles in bar pp collisions using the Collider Detector at Fermilab based on an integrated luminosity of 3.54 pb-1. Both unit and fractionally charged particles are considered. Cross-section upper limits are determined for masses from 50 to 500 GeV/c2. Theoretical cross sections are used to set bounds on the mass of fermionic color triplets, sextets, octets, and decuplets as well as scalar triplets

  6. Nuclear data needs in nuclear astrophysics: Charged-particle reactions

    International Nuclear Information System (INIS)

    Progress in understanding a diverse range of astrophysical phenomena - such as the Big Bang, the Sun, the evolution of stars, and stellar explosions - can be significantly aided by improved compilation, evaluation, and dissemination of charged-particle nuclear reaction data. A summary of the charged-particle reaction data needs in these and other astrophysical scenarios is presented, along with recommended future nuclear data projects. (author)

  7. Analogies between light optics and charged-particle optics

    OpenAIRE

    Khan, Sameen Ahmed

    2002-01-01

    The close analogy between geometrical optics and the classical theories of charged-particle beam optics have been known for a very long time. In recent years, quantum theories of charged-particle beam optics have been presented with the very expected feature of wavelength-dependent effects. With the current development of non-traditional prescriptions of Helmholtz and Maxwell optics respectively, accompanied with the wavelength-dependent effects, it is seen that the analogy between the two sy...

  8. Proposal to Search for Magnetically Charged Particles with Magnetic Charge 1e

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, Michael K. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Fryberger, David [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-11-02

    A model for composite elementary Standard Model (SM) particles based upon magnetically bound vorton pairs, we briefly introduce here, predicts the existence of a complete family of magnetically charged particles, as well as their neutral isotopic partners (all counterparts to the SM elementary particles), in which the lowest mass (charged) particle would be an electrically neutral stable lepton, but which carries a magnetic charge equivalent to 1e. This new particle, which we call a magneticon (a counterpart to the electron) would be pair produced at all e+e- colliders at an Ecm above twice its mass. In addition, PP and PPbar colliders should also be able to produce these new particles through the Drell-Yan process. To our knowledge, no monopole search experiment has been sensitive to such a low-charged magnetic monopole above a particle mass of about 5 GeV/c2. Hence, we propose that a search for such a stable particle of magnetic charge 1e should be undertaken. We have taken the ATLAS detector at the LHC as an example in which this search might be done. To this end, we modeled the magnetic fields and muon trigger chambers of this detector. We show results from a simple Monte Carlo simulation program to indicate how these particles might look in the detector and describe how one might search for these new particles in the ATLAS data stream.

  9. Asymptotic algebra for charged particles and radiation

    International Nuclear Information System (INIS)

    A C*-algebra of asymptotic fields which properly describes the infrared structure in quantum electrodynamics is proposed. The algebra is generated by the null asymptotic of electromagnetic field and the time asymptotic of charged matter fields which incorporate the corresponding Coulomb fields. As a consequence Gauss' law is satisfied in the algebraic setting. Within this algebra the observables can be identified by the principle of gauge invariance. A class of representations of the asymptotic algebra is constructed which resembles the Kulish-Faddeev treatment of electrically charged asymptotic fields. (orig.)

  10. Indirect Charged Particle Detection: Concepts and a Classroom Demonstration

    Science.gov (United States)

    Childs, Nicholas B.; Horányi, Mihály; Collette, Andrew

    2013-01-01

    We describe the principles of macroscopic charged particle detection in the laboratory and their connections to concepts taught in the physics classroom. Electrostatic dust accelerator systems, capable of launching charged dust grains at hypervelocities (1-100 km/s), are a critical tool for space exploration. Dust grains in space typically have…

  11. An improved search for elementary particles with fractional electric charge

    International Nuclear Information System (INIS)

    The SLAC Quark Search Group has demonstrated successful operation of a low cost, high mass throughput Millikan apparatus designed to search for fractionally charged particles. About six million silicone oil drops were measured with no evidence of fractional charges. A second experiment is under construction with 100 times greater throughput which will utilize optimized search fluids

  12. Measurements of Charge Transfer Efficiency in a Proton-irradiated Swept Charge Device

    CERN Document Server

    YuSa, Wang; XiaoYan, Liu; WeiWei, Cui; YuPeng, Xu; ChengKui, Li; MaoShun, Li; DaWei, Han; TianXiang, Chen; Jia, Huo; Juan, Wang; Wei, Li; Wei, Hu; Yi, Zhang; Bo, Lu; GuoHe, Yin; Yue, Zhu; ZiLiang, Zhang

    2013-01-01

    Charge Coupled Devices (CCDs) have been successfully used in several low energy X-ray astronomical satellite over the past two decades. Their high energy resolution and high spatial resolution make them an perfect tool for low energy astronomy, such as formation of galaxy clusters and environment of black holes. The Low Energy X-ray Telescope (LE) group is developing Swept Charge Device (SCD) for the Hard X-ray Modulation Telescope (HXMT) satellite. SCD is a special low energy X-ray CCD, which could be read out a thousand times faster than traditional CCDs, simultaneously keeping excellent energy resolution. A test method for measuring the charge transfer efficiency (CTE) of a prototype SCD has been set up. Studies of the charge transfer inefficiency (CTI) have been performed at a temperature range of operation, with a proton-irradiated SCD.

  13. Charged particle separation by an electrically tunable nanoporous membrane

    International Nuclear Information System (INIS)

    We study the applicability of an electrically tunable nanoporous semiconductor membrane for the separation of nanoparticles by charge. We show that this type of membrane can overcome one of the major shortcomings of nanoporous membrane applications for particle separation: the compromise between membrane selectivity and permeability. The computational model that we have developed describes the electrostatic potential distribution within the system and tracks the movement of the filtered particle using Brownian dynamics while taking into consideration effects from dielectrophoresis, fluid flow, and electric potentials. We found that for our specific pore geometry, the dielectrophoresis plays a negligible role in the particle dynamics. By comparing the results for charged and uncharged particles, we show that for the optimal combination of applied electrolyte and membrane biases the same membrane can effectively separate same-sized particles based on charge with a difference of up to 3 times in membrane permeability. (paper)

  14. Charged Particle Diffusion in Isotropic Random Static Magnetic Fields

    Science.gov (United States)

    Subedi, P.; Sonsrettee, W.; Matthaeus, W. H.; Ruffolo, D. J.; Wan, M.; Montgomery, D.

    2013-12-01

    Study of the transport and diffusion of charged particles in a turbulent magnetic field remains a subject of considerable interest. Research has most frequently concentrated on determining the diffusion coefficient in the presence of a mean magnetic field. Here we consider Diffusion of charged particles in fully three dimensional statistically isotropic magnetic field turbulence with no mean field which is pertinent to many astrophysical situations. We classify different regions of particle energy depending upon the ratio of Larmor radius of the charged particle to the characteristic outer length scale of turbulence. We propose three different theoretical models to calculate the diffusion coefficient each applicable to a distinct range of particle energies. The theoretical results are compared with those from computer simulations, showing very good agreement.

  15. Simulation of non-charged particles

    International Nuclear Information System (INIS)

    This paper presents the method used to simulate the transport of neutral particles by using a Monte Carlo method with accelerating techniques of convergence based on the importance function by the method of first collision probabilities

  16. Study of charge collection and noise in non-irradiated and irradiated silicon detectors

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, C. [Montreal Univ., PQ (Canada); Bates, S. [CERN, ECP, CH-1211 Geneva (Switzerland); Dezillie, B. [CERN, ECP, CH-1211 Geneva (Switzerland); Glaser, M. [CERN, ECP, CH-1211 Geneva (Switzerland); Lemeilleur, F. [CERN, ECP, CH-1211 Geneva (Switzerland); Trigger, I. [Montreal Univ., PQ (Canada)

    1997-04-01

    Charge collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time ({theta}) and fluence ({Phi}), up to about 1.2 x 10{sup 14} protons cm{sup -2}, for minimum ionizing electrons yielded by a {sup 106}Ru source. The noise of irradiated detectors is found dominated for short shaping times ({theta}{<=}50 ns) by a series noise component while for longer shaping time ({theta}{>=}80 ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnitude smaller compared with irradiated detectors, the series noise dominates over the whole range of shaping times investigated (20-150 ns). A signal degradation is observed for irradiated detectors. However, the signal can be distinguished from noise, even after a fluence of about 1.2 x 10{sup 14} protons cm{sup -2}, at a temperature of 6 C and with a shaping time typical of LHC inter-bunch crossing time (20-30 ns). The measurement of the signal as a function of voltage shows that irradiated detectors depleted at 50% of the full depletion voltage can still provide a measurable signal-to-noise ratio. (orig.).

  17. A high sensitivity selector for charged particles

    International Nuclear Information System (INIS)

    The electrostatic size selector for aerosol particles, is composed of two coaxial parallel conductive disks between which an electric field is established; an annular slot in the first disk allows for the atmosphere air intake. Suction and injection systems, and a third intermediate disk are used to carry out a dynamic confinement that allows for the separation of the particles having the required electric mobility and therefore the required size

  18. Charged particle detectors with active detector surface for partial energy deposition of the charged particles and related methods

    Science.gov (United States)

    Gerts, David W; Bean, Robert S; Metcalf, Richard R

    2013-02-19

    A radiation detector is disclosed. The radiation detector comprises an active detector surface configured to generate charge carriers in response to charged particles associated with incident radiation. The active detector surface is further configured with a sufficient thickness for a partial energy deposition of the charged particles to occur and permit the charged particles to pass through the active detector surface. The radiation detector further comprises a plurality of voltage leads coupled to the active detector surface. The plurality of voltage leads is configured to couple to a voltage source to generate a voltage drop across the active detector surface and to separate the charge carriers into a plurality of electrons and holes for detection. The active detector surface may comprise one or more graphene layers. Timing data between active detector surfaces may be used to determine energy of the incident radiation. Other apparatuses and methods are disclosed herein.

  19. The use of radiochromic films to measure and analyze the beam profile of charged particle accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Avila-Rodriguez, M.A. [Edmonton PET Centre, Cross Cancer Institute, 11560 University Ave, Edmonton, AB T6G 1Z2 (Canada); Unidad PET/CT-Ciclotron, Facultad de Medicina, Universidad Nacional Autonoma de Mexico (Mexico)], E-mail: avilarod@uwalumni.com; Wilson, J.S.; McQuarrie, S.A. [Edmonton PET Centre, Cross Cancer Institute, 11560 University Ave, Edmonton, AB T6G 1Z2 (Canada)

    2009-11-15

    The use of radiochromic films as a simple and inexpensive tool to accurately measure and analyze the beam profile of charged particle accelerators is described. In this study, metallic foils of different materials and thicknesses were irradiated with 17.8 MeV protons and autoradiographic images of the beam strike were acquired by exposing pieces of RCF in direct contact with the irradiated foils. The films were digitalized using a conventional scanner and images were analyzed using DoseLab. Beam intensity distributions, isodose curves and linear beam profiles of the digitalized images were acquired.

  20. The use of radiochromic films to measure and analyze the beam profile of charged particle accelerators.

    Science.gov (United States)

    Avila-Rodriguez, M A; Wilson, J S; McQuarrie, S A

    2009-11-01

    The use of radiochromic films as a simple and inexpensive tool to accurately measure and analyze the beam profile of charged particle accelerators is described. In this study, metallic foils of different materials and thicknesses were irradiated with 17.8MeV protons and autoradiographic images of the beam strike were acquired by exposing pieces of RCF in direct contact with the irradiated foils. The films were digitalized using a conventional scanner and images were analyzed using DoseLab. Beam intensity distributions, isodose curves and linear beam profiles of the digitalized images were acquired. PMID:19054679

  1. Apolipoprotein E expression and behavioral toxicity of high charge, high energy (HZE) particle radiation

    International Nuclear Information System (INIS)

    Apolipoprotein E (apoE) is a lipid binding protein that plays an important role in tissue repair following brain injury. In the present studies, we have investigated whether apoE affects the behavioral toxicity of high charge, high energy (HZE) particle radiation. Sixteen male apoE knockout (KO) mice and sixteen genetically matched wild-type (WT) C57BL mice were used in this experiment. Half of the KO and half of the WT animals were irradiated with 600 MeV/amu iron particles (2 Gy whole body). The effect of irradiation on motor coordination and stamina (Rotarod test), exploratory behavior (open field test), and spatial working and reference memory (Morris water maze) was assessed. Rotarod test: Performance was adversely affected by radiation exposure in both KO and WT groups at 30 d after irradiation. By 60 d after radiation, the radiation effect was lost in WT, but still apparent in irradiated KO mice. Open field test: Radiation reduced open field exploratory activity 14, 28, 56, 84, and 168 d after irradiation of KO mice, but had no effect on WT mice. Morris water maze: Radiation adversely affected spatial working memory in the KO mice, but had no discernible effect in the WT mice as assessed 180 d after irradiation. In contrast, irradiated WT mice showed marked impairment of spatial reference memory in comparison to non-irradiated mice, while no effect of radiation was observed in KO mice. These studies show that apoE expression influences the behavioral toxicity of HZE particle radiation and suggest that apoE plays a role in the repair/recovery from radiation injury of the central nervous system (CNS). ApoE deficiency may exacerbate the previously reported effects of HZE particle radiation in accelerating the brain aging process. (author)

  2. Acceleration of low energy charged particles by gravitational waves

    OpenAIRE

    Voyatzis, G.; Vlahos, L.; Ichtiaroglou, S.; Papadopoulos, D.

    2005-01-01

    The acceleration of charged particles in the presence of a magnetic field and gravitational waves is under consideration. It is shown that the weak gravitational waves can cause the acceleration of low energy particles under appropriate conditions. Such conditions may be satisfied close to the source of the gravitational waves if the magnetized plasma is in a turbulent state.

  3. Ionic charge state measurements in solar energetic particle events

    International Nuclear Information System (INIS)

    With the launch of the Advanced Composition Explorer, it has become possible through the SEPICA instrument to make direct ionic charge state measurements for individual Solar Energetic Particle events. In large events, the charge state may even be measured as a function of time, revealing changes that may be created by phenomena such as injections from different acceleration mechanisms, or confinement by magnetic field structures. The charge state can be a sensitive indicator of separate SEP populations. Several examples of SEP events will be presented. One of these, the November, 1997 event, displayed a trend in which the mean charge state for several ions increased with energy. These measurements may be the result of several processes, including a mixture of plasma with different source and acceleration histories, and abundance formation and possibly additional charge state modification by collisional or other means in the corona. A wide range of iron charge states have been measured for a variety of SEP events, ranging from =10+ to 20+. The mean charge states of C, O, Ne, Mg and Si all increased as the iron charge state increased. In events with the highest iron charge states, there were abundance enhancements in Ne with respect to oxygen in those cases, even though the mass/charge of the O and Ne were similar. In events with the lowest iron charge states, all these ions except Mg showed mean charge states generally consistent with coronal material of an equilibrium temperature of 1.3-1.6 million degrees K

  4. Generalized charge symmetry and charmed particle decays

    International Nuclear Information System (INIS)

    The charge symmetry operations are introduced within the c, s and p, n quark doublets and its consequences for weak decays proceeding via the GIM current, are studied. Numerous relations between various decays are obtained. Combined with CP an interesting pattern of allowed and suppressed amplitudes for charmed meson and baryon processes is found. The results are compatible with the present meagre experimental information. (Auth.)

  5. Charged particle acceleration by electron beam in corrugated plasma waveguide

    International Nuclear Information System (INIS)

    A two-beam charged particle acceleration scheme in a plasma waveguide with corrugated conducting walls is considered. The guiding heavy-current relativistic electron beam is in synchronism with the first plasma wave space harmonics and the accelerated beam is synchronism with a quicker plasma wave. In this case under weak corrugation of the wall the accelerating resonance field effecting the accelerated particles notably increases the field braking the guiding beam. The process of plasma wave excitation with regard to the guiding beam space charge and the relativistic particle acceleration dynamics are investigated by numeric methods. Optimal acceleration modes are found. 19 refs.; 12 figs

  6. Charged particles detection: the draft-and-dye method

    International Nuclear Information System (INIS)

    Charged particles travelling through an organic medium leave a trail of highly concentrated active, stable chemical radicals. These functions are able to initiate copolymerization reactions of unsaturated molecules. Such a reagent is made to reach the trail; polymerization occurs. If the new polymer formed either absorbs or emits light the track of the charged particle is made visible. This technique and results are discussed: the efficiency of those detectors has been increased, they do not exhibit any critical dip angle for the registration of particle tracks, they may offer a way to reveal tracks originating in the detector itself. (orig.)

  7. Charged particles detection: the graft-and-dye method

    International Nuclear Information System (INIS)

    Charged particles travelling through an organic medium leave a trail of highly concentrated active, stable chemical radicals. These functions are able to initiate copolymerization reactions of unsaturated molecules. Such a reagent is made to reach the trail; polymerization occurs. If the new polymer formed either absorbs or emits light the track of the charged particle is made visible. This technique and results are discussed: the efficiency of those detectors has been increased, they do not exhibit any critical dip angle for the registration of particle tracks, they may offer a way to reveal tracks originating in the detector itself. (author)

  8. Sources for charged particles; Les sources de particules chargees

    Energy Technology Data Exchange (ETDEWEB)

    Arianer, J.

    1997-09-01

    This document is a basic course on charged particle sources for post-graduate students and thematic schools on large facilities and accelerator physics. A simple but precise description of the creation and the emission of charged particles is presented. This course relies on every year upgraded reference documents. Following relevant topics are considered: electronic emission processes, technological and practical considerations on electron guns, positron sources, production of neutral atoms, ionization, plasma and discharge, different types of positive and negative ion sources, polarized particle sources, materials for the construction of ion sources, low energy beam production and transport. (N.T.).

  9. Blister formation on tungsten damaged by high energy particle irradiation

    International Nuclear Information System (INIS)

    In order to investigate the effect of radiation damage on hydrogen behavior in tungsten, tungsten samples with radiation damage of up to 3.5 dpa were irradiated by a mixed hydrogen-carbon ion beam. The radiation damage was produced with 700 keV negative hydrogen ion beam irradiation. The number density of blisters produced by the mixed ion beam irradiation decreased with increasing radiation damage. This was especially observed for blisters with diameters of 20 μm or less. This result showed that radiation damage produced by high-energy particle irradiation suppresses blister formation on tungsten surfaces

  10. An update on (n,charged particle) research at WNR

    Energy Technology Data Exchange (ETDEWEB)

    Haight, R.C.; Bateman, F.B.; Sterbenz, S.M. [Los Alamos National Lab., NM (United States); Grimes, S.M. [Ohio Univ., Athens, OH (United States); Wasson, O.A. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Maier-Komor, P. [T.U. Munich (Germany); Vonach, H. [Inst. fuer Radiumforschung und Kernphysik, Vienna (Austria)

    1995-12-31

    Neutron-induced reactions producing light charged particles continue to be investigated at the spallation fast-neutron source at the Los Alamos Neutron Science Center (LANSCE). New data on the cross sections for alpha-particle production for neutrons on {sup 58}Ni and {sup 60}Ni are presented from threshold to 50 MeV. Recent changes in the experiment now allow protons, deuterons, tritons, {sup 3}He and alpha particles to be identified.

  11. An update on (n,charged particle) research at WNR

    International Nuclear Information System (INIS)

    Neutron-induced reactions producing light charged particles continue to be investigated at the spallation fast-neutron source at the Los Alamos Neutron Science Center (LANSCE). New data on the cross sections for alpha-particle production for neutrons on 58Ni and 60Ni are presented from threshold to 50 MeV. Recent changes in the experiment now allow protons, deuterons, tritons, 3He and alpha particles to be identified

  12. Motions of charged particles in Goedel-type spacetimes

    International Nuclear Information System (INIS)

    Goedel-type spacetimes in Hehl's non propagating torsion theory are reconsidered by supposing that the curvature source is a Weyssenhoff-Raab fluid and an electromagnetic field. The electromagnetic field implies space time homogeneity and admits a dual interpretation. From the trajectories of the test particles, it is shown that there is a class of such spacetimes for which charged particles can reach regions inaccessible to neutral particles or even photons. (author). 21 refs., 1 fig

  13. Motions of charged particles in Goedel-type spacetimes

    Energy Technology Data Exchange (ETDEWEB)

    Figueiredo, Bartolomeu D.B. [Centro Brasileiro de Pesquisas Fisicas (CBPF), Rio de Janeiro, RJ (Brazil)

    1996-10-01

    Goedel-type spacetimes in Hehl`s non propagating torsion theory are reconsidered by supposing that the curvature source is a Weyssenhoff-Raab fluid and an electromagnetic field. The electromagnetic field implies space time homogeneity and admits a dual interpretation. From the trajectories of the test particles, it is shown that there is a class of such spacetimes for which charged particles can reach regions inaccessible to neutral particles or even photons. (author). 21 refs., 1 fig.

  14. Atmosphere turbulence effect on the hot particle charge

    International Nuclear Information System (INIS)

    The charging of hot beta-active aerosol articles of the micron size range in the turbulent current has been studied experimentally . For this purpose hot particles, obtained by the neutron activation of gold placed on the surface of glass microspheres by the cathode spraying method, were introduced into the turbulent current with the Reynolds number of 104 - 105. Results of the determination of particle charges within the current velocity range from 0.5 to 3 m/s confirm the reliability of the previously obtained model of the charging of hot particles in the turbulent current of the near - ground atmospere layer which is described by the function directly proportional to the radius of particles and the half-cube of the wind velocity, and inversely proportional to the square root of the height. The scheme is suggested and specific features are described of experimental installations used in the process of studies

  15. Doubly-charged particles at the Large Hadron Collider

    CERN Document Server

    Alloul, Adam; Fuks, Benjamin; de Traubenberg, Michel Rausch

    2013-01-01

    In this work we investigate the production and signatures of doubly-charged particles at the Large Hadron Collider. We start with the Standard Model particle content and representations and add generic doubly-charged exotic particles. We classify these doubly-charged states according to their spin, considering scalar, fermionic and vectorial fields, and according to their SU(2)L representation, being chosen to be either trivial, fundamental, or adjoint. We write the most general interactions between them and the Standard Model sector and study their production modes and possible decay channels. We then probe how they can most likely be observed and how particles with different spin and SU(2)L representations could be possibly distinguished.

  16. Quantum theory of relativistic charged particles in external fields

    International Nuclear Information System (INIS)

    A study was made on external field theories in which the quantized field corresponds to relativistic elementary particles with non-zero rest mass. These particles are assumed to be charged, thus they have distinct antiparticles. The thesis consists of two parts. The first tries to accommodate the general features of theories of relativistic charged particles in external fields. Spin and dynamics in particular are not specified. In the second part, the results are applied to charged spin-1/2 and spin-0 particles, the dynamics of which are given by the Dirac resp. Klein-Gordon equation. The greater emphasis is on external fields which are rapidly decreasing, infinitely differentiable functions of space-time, but also considers time-independent fields. External fields, other than electromagnetic fields are also considered, e.g. scalar fields

  17. Heavy charged-particle treatment planning

    International Nuclear Information System (INIS)

    An essential element of the heavy-ion radiotherapy program is the development of a computerized treatment planning system. A computerized tomographic (CT) based system is currently in operation, where sequential scans are first displayed on a dedicated raster graphics display unit. Target contours in appropriate slices are then entered via cursor by the radiotherapist. After the entry angle and ion type are chosen, the treatment planning program uses CT data on a pixel-by-pixel basis to (1) design appropriate compensators to contour the stopping region of the therapy beams, (2) select an appropriate spread Bragg peak for the irradiation, (3) design a collimator aperture for each entry portal, and (4) generate isoeffect and physical dose distributions overlayed on the CT image. In this section, we review progress in the area of clinical physics, and outline future lines of investigation

  18. Relativistic mixtures of charged and uncharged particles

    Science.gov (United States)

    Kremer, Gilberto M.

    2014-01-01

    Mixtures of relativistic gases within the framework of Boltzmann equation are analyzed. Three systems are considered. The first one refers to a mixture of uncharged particles by using Grad's moment method, where the relativistic mixture is characterized by the moments of the distribution functions: particle four-flows, energy-momentum tensors, and third-order moment tensors. In the second Fick's law for a mixture of relativistic gases of non-disparate rest masses in a Schwarzschild metric are derived from an extension of Marle and McCormack model equations applied to a relativistic truncated Grad's distribution function, where it is shown the dependence of the diffusion coefficient on the gravitational potential. The third one consists in the derivation of the relativistic laws of Ohm and Fourier for a binary mixtures of electrons with protons and electrons with photons subjected to external electromagnetic fields and in presence of gravitational fields by using the Anderson and Witting model of the Boltzmann equation.

  19. Nanoparticle production by UV irradiation of combustion generated soot particles

    International Nuclear Information System (INIS)

    Laser ablation of surfaces normally produce high temperature plasmas that are difficult to control. By irradiating small particles in the gas phase, we can better control the size and concentration of the resulting particles when different materials are photofragmented. Here, we irradiate soot with 193 nm light from an ArF excimer laser. Irradiating the original agglomerated particles at fluences ranging from 0.07 to 0.26 J/cm2 with repetition rates of 20 and 100 Hz produces a large number of small, unagglomerated particles, and a smaller number of spherical agglomerated particles. Mean particle diameters from 20 to 50 nm are produced from soot originally having a mean electric mobility diameter of 265 nm. We use a non-dimensional parameter, called the photon-atom ratio (PAR), to aid in understanding the photofragmentation process. This parameter is the ratio of the number of photons striking the soot particles to the number of the carbon atoms contained in the soot particles, and is a better metric than the laser fluence for analyzing laser-particle interactions. These results suggest that UV photofragmentation can be effective in controlling particle size and morphology, and can be a useful diagnostic for studying elements of the laser ablation process

  20. Nanoparticle production by UV irradiation of combustion generated soot particles

    International Nuclear Information System (INIS)

    Laser ablation of surfaces normally produce high temperature plasmas that are difficult to control. By irradiating small particles in the gas phase, we can better control the size and concentration of the resulting particles when different materials are photofragmented. Here, we irradiate soot with 193 nm light from an ArF excimer laser. Irradiating the original agglomerated particles at fluences ranging from 0.07 to 0.26 J/cm2 with repetition rates of 20 and 100 Hz produces a large number of small, unagglomerated particles, and a smaller number of spherical agglomerated particles. Mean particle diameters from 20 to 50 nm are produced from soot originally having a mean electric mobility diameter of 265nm. We use a non-dimensional parameter, called the photon/atom ratio (PAR), to aid in understanding the photofragmentation process. This parameter is the ratio of the number of photons striking the soot particles to the number of the carbon atoms contained in the soot particles, and is a better metric than the laser fluence for analyzing laser-particle interactions. These results suggest that UV photofragmentation can be effective in controlling particle size and morphology, and can be a useful diagnostic for studying elements of the laser ablation process

  1. Bibliography of integral charged particle nuclear data

    International Nuclear Information System (INIS)

    This bibliography is divided into three main sections covering experimental, theoretical, and review references. The review section also includes compilation and evaluation references. Each section contains two subsections. The main subsection contains all references satisfying the criteria noted above and the second subsection is devoted to isotope production. The main subsections are ordered by increasing Z and A of the incident particle, then by increasing Z and A of the target nucleus. Within this order, the entries are ordered by residual nucleus and quantity (e.g., sigma(E)). Finally, the entries are ordered by outgoing particles or processes. All entries which have the same target, reaction, and quantity are grouped under a common heading with the most recent reference first. As noted above the second subsection is devoted to isotope production and is limited in the information it carries. Only those references which contain data on a definite residual nucleus or group of nuclei (e.g., fission fragments) are included in these subsections. Entries within these second subsections are ordered by increasing Z and A of the isotope produced and then by quantity. All references containing data on the same isotope production and quantity are grouped together. All lines within a group are ordered by increasing Z and A of the target and then of the incident particle. The final ordering is by increasing minimum energy

  2. Bibliography of integral charged particle nuclear data

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, T.W.; Burt, J.S.

    1977-03-01

    This bibliography is divided into three main sections covering experimental, theoretical, and review references. The review section also includes compilation and evaluation references. Each section contains two subsections. The main subsection contains all references satisfying the criteria noted above and the second subsection is devoted to isotope production. The main subsections are ordered by increasing Z and A of the incident particle, then by increasing Z and A of the target nucleus. Within this order, the entries are ordered by residual nucleus and quantity (e.g., sigma(E)). Finally, the entries are ordered by outgoing particles or processes. All entries which have the same target, reaction, and quantity are grouped under a common heading with the most recent reference first. As noted above the second subsection is devoted to isotope production and is limited in the information it carries. Only those references which contain data on a definite residual nucleus or group of nuclei (e.g., fission fragments) are included in these subsections. Entries within these second subsections are ordered by increasing Z and A of the isotope produced and then by quantity. All references containing data on the same isotope production and quantity are grouped together. All lines within a group are ordered by increasing Z and A of the target and then of the incident particle. The final ordering is by increasing minimum energy.

  3. Charged-particle spectroscopy in organic semiconducting single crystals

    Science.gov (United States)

    Ciavatti, A.; Sellin, P. J.; Basiricò, L.; Fraleoni-Morgera, A.; Fraboni, B.

    2016-04-01

    The use of organic materials as radiation detectors has grown, due to the easy processability in liquid phase at room temperature and the possibility to cover large areas by means of low cost deposition techniques. Direct charged-particle detectors based on solution-grown Organic Semiconducting Single Crystals (OSSCs) are shown to be capable to detect charged particles in pulse mode, with very good peak discrimination. The direct charged-particle detection in OSSCs has been assessed both in the planar and in the vertical axes, and a digital pulse processing algorithm has been used to perform pulse height spectroscopy and to study the charge collection efficiency as a function of the applied bias voltage. Taking advantage of the charge spectroscopy and the good peak discrimination of pulse height spectra, an Hecht-like behavior of OSSCs radiation detectors is demonstrated. It has been possible to estimate the mobility-lifetime value in organic materials, a fundamental parameter for the characterization of radiation detectors, whose results are equal to μτcoplanar = (5 .5 ± 0.6 ) × 10-6 cm2/V and μτsandwich = (1 .9 ± 0.2 ) × 10-6 cm2/V, values comparable to those of polycrystalline inorganic detectors. Moreover, alpha particles Time-of-Flight experiments have been carried out to estimate the drift mobility value. The results reported here indicate how charged-particle detectors based on OSSCs possess a great potential as low-cost, large area, solid-state direct detectors operating at room temperature. More interestingly, the good detection efficiency and peak discrimination observed for charged-particle detection in organic materials (hydrogen-rich molecules) are encouraging for their further exploitation in the detection of thermal and high-energy neutrons.

  4. Investigating forces between charged particles in the presence of oppositely charged polyelectrolytes with the multi-particle colloidal probe technique.

    Science.gov (United States)

    Borkovec, Michal; Szilagyi, Istvan; Popa, Ionel; Finessi, Marco; Sinha, Prashant; Maroni, Plinio; Papastavrou, Georg

    2012-11-01

    Direct force measurements are used to obtain a comprehensive picture of interaction forces acting between charged colloidal particles in the presence of oppositely charged polyelectrolytes. These measurements are achieved by the multi-particle colloidal probe technique based on the atomic force microscope (AFM). This novel extension of the classical colloidal probe technique offers three main advantages. First, the technique works in a colloidal suspension with a huge internal surface area of several square meters, which simplifies the precise dosing of the small amounts of the polyelectrolytes needed and makes this approach less sensitive to impurities. Second, the particles are attached in-situ within the fluid cell, which avoids the formation of nanobubbles on the latex particles used. Third, forces between two similar particles from the same batch are being measured, which allows an unambiguous determination of the surface potential due to the symmetry of the system. Based on such direct force measurements involving positively and negatively charged latex particles and different polyelectrolytes, we find the following forces to be relevant. Repulsive electrostatic double-layer forces and attractive van der Waals forces as described by the theory of Derjaguin, Landau, Verwey, and Overbeek (DLVO) are both important in these systems, whereby the electrostatic forces dominate away from the isoelectric point (IEP), while at this point they vanish. Additional non-DLVO attractive forces are operational, and they have been identified to originate from the electrostatic interactions between the patch-charge heterogeneities of the adsorbed polyelectrolyte films. Highly charged polyelectrolytes induce strong patch-charge attractions, which become especially important at low ionic strengths and high molecular mass. More weakly charged polyelectrolytes seem to form more homogeneous films, whereby patch-charge attractions may become negligible. Individual bridging events

  5. Evaluation of the relative TL efficiency of the thermoluminescent detectors to heavy charged particles.

    Science.gov (United States)

    Sądel, M; Bilski, P; Swakoń, J; Weber, A

    2016-01-01

    The relative thermoluminescence efficiency, η, is in general not constant but depends on ionisation density. Evaluation of the η is therefore important especially for correct interpretation of measurements of densely ionising radiation doses in proton radiotherapy or in space dosimetry. The correct determination of the η is not always straightforward especially when more strongly ionising radiation is to be measured. In the present work, the process of calculation of the η based on two kinds of heavy charged particles was studied. Several factors which may influence the value of the η and their significance for the final result were discussed. These include for example non-uniform deposition of the dose within the detector volume, self-attenuation of thermoluminescent light, choice of the reference radiation, etc. The presented approach was applied to the experimental results of η of LiF:Mg,Ti detectors irradiated with two kinds of heavy charged particles, protons and alpha particles. PMID:25656042

  6. Evaluation of the relative TL efficiency of the thermoluminescent detectors to heavy charged particles

    International Nuclear Information System (INIS)

    The relative thermoluminescence efficiency, η, is in general not constant but depends on ionisation density. Evaluation of the η is therefore important especially for correct interpretation of measurements of densely ionising radiation doses in proton radiotherapy or in space dosimetry. The correct determination of the η is not always straightforward especially when more strongly ionising radiation is to be measured. In the present work, the process of calculation of the η based on two kinds of heavy charged particles was studied. Several factors which may influence the value of the η and their significance for the final result were discussed. These include for example non-uniform deposition of the dose within the detector volume, self-attenuation of thermoluminescent light, choice of the reference radiation, etc. The presented approach was applied to the experimental results of η of LiF:Mg,Ti detectors irradiated with two kinds of heavy charged particles, protons and alpha particles. (authors)

  7. Trapped charged particles a graduate textbook with problems and solutions

    CERN Document Server

    Madsen, Niels; Thompson, Richard C

    2016-01-01

    At Les Houches in January 2015, experts in the field of particle trapping came together to discuss the fundamental physics of traps and the different types of applications. This textbook collates the lectures delivered there; the Second Winter School on Physics with Trapped Charged Particles. Taken as a whole, the book gives an overview of why traps for charged particles are important, how they work, their special features and limitations, and their application in areas such as precision measurements, mass spectrometry, optical clocks, plasma physics, antihydrogen creation, quantum simulation and quantum information processing. Chapters from various world experts include those on the basic properties of Penning traps, RF traps and particle accelerators, as well as those covering important practical aspects such as vacuum systems, detection techniques, and different types of particle cooling including laser cooling. Finally, individual chapters deal with the different areas of application listed above. Each ...

  8. Measuring massive metastable charged particles with ATLAS RPC timing information.

    CERN Document Server

    Ellis, Jonathan Richard; Oye, Ola Kristoffer

    2006-01-01

    We investigate the measurement of massive metastable charged particles in ATLAS, using timing information from the resistive plate chambers (RPCs). As representative particle candidates we use staus, the partners of $ au$ leptons in supersymmetric models with gravitino dark matter (GDM), which may well be stable on the scale of the detector. The generic signatures of massive metastable charged particles are a long Time-of-Flight (ToF) and high energy-loss ($dE/dx$). The RPC timing information allows us to measure the ToF of a particle which, taken in conjunction with the measurement of the particle's momentum from its track, allows one to determine its mass. We pioneer the study of the RPCs' potential for this measurement. We also consider triggering effects on the event selection, and discuss quantitatively the ATLAS potential for measuring the stau mass in three specific GDM benchmark scenarios.

  9. Charged particle creation in the steady state universe

    International Nuclear Information System (INIS)

    The birth of a particle of charge q(0), initial mass m(0), and radius a in the steady state universe is studied. With the particle's birth, in accord with causality, gravity, and Coulomb fields propagate away from it with the speed of light. Field energies are supplied by the particle's mass which subsequently decays in time. Asymptotic solution to a nonlinear equation for the remaining mass gives the criterion m(0) is greater that q(0)2/2ac2 as a necessary condition for the initial mass to survive the field expansion. The resulting radius of a classical charged particle is found to be greater than the standard value obtained by equating self- and rest-mass energies of the initial particle. 12 refs

  10. Charged particle reaction cross sections and nucleosynthesis

    International Nuclear Information System (INIS)

    The role of proton and α-particle induced reactions in carbon, neon, oxygen and silicon burning in massive stars is surveyed. The problems associated with determining thermonuclear reaction rates for reactions with widely spaced resonances and with closely spaced or overlapping resonances are discussed and the associated experimental approaches are reviewed. Experimental techniques which have been used in the measurement of reaction cross sections are discussed and their strengths and weaknesses are identified. Recent developments in attempts to establish reliable statistical-model codes for calculation of reaction cross sections are presented and discussed. The results of experimental tests of statistical model codes are summarised and evaluated

  11. Behaviour of scintillometers with charge particles

    International Nuclear Information System (INIS)

    The behaviour of a scintillation plastic and an anthracene crystal for protons and deuterons with energies within 0,2 and 1,7 MeV. has been studied. The beam of monoenergetic particles falls directly on the detector in study in optic contact with a photomultiplicator. The impulse get in an amplifier which sends then to a scale a sting as a monitor and to an analyzer of 100 canals. The spectrum for each energy of incidental beam is obtained taking the maximum of the spectrum as the most probable value of amplitude of the detector reply, and this is represented apposite to the energy. (Author) 6 refs

  12. Complex Kepler Orbits and Particle Aggregation in Charged Microscopic Grains

    Science.gov (United States)

    Lee, Victor; Waitukaitis, Scott; Miskin, Marc; Jaeger, Heinrich

    2015-03-01

    Kepler orbits are usually associated with the motion of astronomical objects such as planets or comets. Here we observe such orbits at the microscale in a system of charged, insulating grains. By letting the grains fall freely under vacuum, we eliminate the effects of air drag and gravity, and by imaging them with a co-falling high-speed camera we track the relative positions of individual particles with high spatial and temporal precision. This makes it possible to investigate the behaviors caused by the combination of long-range electrostatic interactions and short-range, dissipative, contact interactions in unprecedented detail. We make the first direct observations of microscopic elliptical and hyperbolic Kepler orbits, collide-and-capture events between pairs of charged grains, and particle-by-particle aggregation into larger clusters. Our findings provide experimental evidence for electrostatic mechanisms that have been suspected, but not previously observed at the single-event level, as driving the early stages of particle aggregation in systems ranging from fluidized particle bed reactors to interstellar protoplanetary disks. Furthermore, since particles of different net charge and size are seen to aggregate into characteristic spatial configurations, our results suggest new possibilities for the formation of charge-stabilized ``granular molecules''. We can reproduce the observed molecule configurations by taking many-body, dielectric polarization effects into account.

  13. Electric birefringence anomaly of solutions of ionically charged anisometric particles.

    Science.gov (United States)

    Hoffmann, H; Gräbner, Dieter

    2015-02-01

    The term "electric birefringence anomaly" is known as the electric birefringence (EB) signal that occurs in solutions of ionically charged anisometric particles in a narrow concentration region. The signal is of opposite sign to the normal birefringence that occurs below and above this narrow concentration region. The normal electric birefringence signals in the dilute and more concentrated regions are due to the orientation of the particles in the direction of the applied electric field. The origin for the anomalous signal was not completely understood until now. The article summarises previous results in which the anomalous results had been observed but not well understood. It shows that the birefringence anomaly occurs in systems as diverse as micellar solutions, polyelectrolytes, solutions of clays, viruses and fibres. In all these systems the anomaly signals are present at the concentration when the length of the colloidal particles including the thickness of the electric double layer are about the same as the mean distance between the colloidal particles. Under these conditions the electric double layers of the particles overlap along the main axis of the particles but not in the direction across the particles. As a consequence of this situation a dipole is built up across the particles by the migration of the counter-ions of the particles in the electric field and this dipole leads to an orientation of the particles perpendicular to the electric field. The anomalous signal can usually be observed simultaneously with the normal signal. The amplitude of the anomalous signal can be larger than the amplitude of the normal signal. As a consequence the total birefringence changes its sign in the anomalous concentration region. The anomaly signal of the clays can also be explained by a fluctuating dipole around the particles, which is due to the fact that the centre of the ionic charges of the particles does not fall on the centre of the ionic charge of the counter

  14. Relativistic mixtures of charged and uncharged particles

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, Gilberto M. [Departamento de Física, Universidade Federal do Paraná, Curitiba (Brazil)

    2014-01-14

    Mixtures of relativistic gases within the framework of Boltzmann equation are analyzed. Three systems are considered. The first one refers to a mixture of uncharged particles by using Grad’s moment method, where the relativistic mixture is characterized by the moments of the distribution functions: particle four-flows, energy-momentum tensors, and third-order moment tensors. In the second Fick’s law for a mixture of relativistic gases of non-disparate rest masses in a Schwarzschild metric are derived from an extension of Marle and McCormack model equations applied to a relativistic truncated Grad’s distribution function, where it is shown the dependence of the diffusion coefficient on the gravitational potential. The third one consists in the derivation of the relativistic laws of Ohm and Fourier for a binary mixtures of electrons with protons and electrons with photons subjected to external electromagnetic fields and in presence of gravitational fields by using the Anderson and Witting model of the Boltzmann equation.

  15. Optimal performance of charged particle telescopes in space

    International Nuclear Information System (INIS)

    A Bayesian probabilistic data analysis method for energetic proton and ion data from charged particle telescopes in space is described. The telescope is assumed to consist of only a series of planar silicon detectors with graduated thicknesses. The method is based on a range-straggling function and makes optimal use of energy loss measurements in each detector. It provides accurate incidence angle estimates for particles stopping in the telescope, allowing accurate element identification and possible isotope identification. It also provides energy estimates for high-energy particles going through the telescope without stopping. Examples are shown for simulated telescope design performance tests and application to real space-particle data

  16. Medical radiation dosimetry theory of charged particle collision energy loss

    CERN Document Server

    McParland, Brian J

    2014-01-01

    Accurate radiation dosimetry is a requirement of radiation oncology, diagnostic radiology and nuclear medicine. It is necessary so as to satisfy the needs of patient safety, therapeutic and diagnostic optimisation, and retrospective epidemiological studies of the biological effects resulting from low absorbed doses of ionising radiation. The radiation absorbed dose received by the patient is the ultimate consequence of the transfer of kinetic energy through collisions between energetic charged particles and atoms of the tissue being traversed. Thus, the ability of the medical physicist to both measure and calculate accurately patient dosimetry demands a deep understanding of the physics of charged particle interactions with matter. Interestingly, the physics of charged particle energy loss has an almost exclusively theoretical basis, thus necessitating an advanced theoretical understanding of the subject in order to apply it appropriately to the clinical regime. ​ Each year, about one-third of the worl...

  17. Charged-Particle Multiplicity in Proton-Proton Collisions

    CERN Document Server

    Grosse-Oetringhaus, Jan Fiete

    2010-01-01

    This article summarizes and critically reviews measurements of charged-particle multiplicity distributions and pseudorapidity densities in p+p(pbar) collisions between sqrt(s) = 23.6 GeV and sqrt(s) = 1.8 TeV. Related theoretical concepts are briefly introduced. Moments of multiplicity distributions are presented as a function of sqrt(s). Feynman scaling, KNO scaling, as well as the description of multiplicity distributions with a single negative binomial distribution and with combinations of two or more negative binomial distributions are discussed. Moreover, similarities between the energy dependence of charged-particle multiplicities in p+p(pbar) and e+e- collisions are studied. Finally, various predictions for pseudorapidity densities, average multiplicities in full phase space, and multiplicity distributions of charged particles in p+p(pbar) collisions at the LHC energies of sqrt(s) = 7 TeV, 10 TeV, and 14 TeV are summarized and compared.

  18. Electromagnetic radiation of charged particles in stochastic motion

    CERN Document Server

    Harko, Tiberiu

    2016-01-01

    The study of the Brownian motion of a charged particle in electric and magnetic fields fields has many important applications in plasma and heavy ions physics, as well as in astrophysics. In the present paper we consider the electromagnetic radiation properties of a charged non-relativistic particle in the presence of electric and magnetic fields, of an exterior non-electromagnetic potential, and of a friction and stochastic force, respectively. We describe the motion of the charged particle by a Langevin and generalized Langevin type stochastic differential equation. We investigate in detail the cases of the Brownian motion with or without memory in a constant electric field, in the presence of an external harmonic potential, and of a constant magnetic field. In all cases the corresponding Langevin equations are solved numerically, and a full description of the spectrum of the emitted radiation and of the physical properties of the motion is obtained. The Power Spectral Density (PSD) of the emitted power is ...

  19. Charge collection studies of proton-irradiated n- and p-type epitaxial silicon detectors

    International Nuclear Information System (INIS)

    Proton-irradiated epitaxial pad diodes of 75, 100 and 150μm thickness and different oxygen concentrations were studied as an option to withstand the extreme radiation environment in the innermost tracking region of the future Super-LHC. With a new TCT setup using red laser light, time-resolved current signals could be measured in 150μm thin diodes. Thus the charge correction method (CCM) could be used to extract the effective trapping times. Similar results compared to previously investigated materials were obtained if the standard model of trapping is assumed, which is based on a constant trapping time at each fluence and neglects detrapping and charge multiplication. Charge collection efficiency (CCE) measured with 5.8 MeV α-particles showed an increase for decreasing thickness, but no dependence on impurity concentration was seen. CCE simulations based on the effective trapping time constants determined with the CCM resulted in systematically lower values than the measurements. This is the case for the CCE of both α-particles, red and infrared laser light. To account for this, possible modifications of the trapping model including voltage- or field-dependent trapping times will be discussed. Moreover, at high fluences and voltages anomalously high CCE>1 was observed, which indicates charge multiplication effects.

  20. Charged Massive Particle's Tunneling From Charged Non-Rotating Micro Black Hole

    CERN Document Server

    Soleimani, M J; Radiman, Shahidan; Abdullah, W A T Wan

    2015-01-01

    In the tunneling framework of Hawking radiation, charged massive particle's tunneling in charged non-rotating TeV-Scale black hole is investigated. To this end, we consider natural cutoffs as a minimal length, a minimal momentum, and a maximal momentum through a generalized uncertainty principle. We focus on the role played by these natural cutoffs on the luminosity of charged non-rotating micro black hole by taking into account the full implications of energy and charge conservation as well as the back- scattered radiation.

  1. Clustering of settling charged particles in turbulence: theory and experiments

    Energy Technology Data Exchange (ETDEWEB)

    Lu Jiang; Nordsiek, Hansen; Shaw, Raymond A, E-mail: rashaw@mtu.edu [Department of Physics, Michigan Technological University, 1400 Townsend Drive, Houghton, MI 49931 (United States)

    2010-12-15

    Atmospheric clouds, electrosprays and protoplanetary nebula (dusty plasma) contain electrically charged particles embedded in turbulent flows, often under the influence of an externally imposed, approximately uniform gravitational or electric force. We have developed a theoretical description of the dynamics of such systems of charged, sedimenting particles in turbulence, allowing radial distribution functions (RDFs) to be predicted for both monodisperse and bidisperse particle size distributions. The governing parameters are the particle Stokes number (particle inertial time scale relative to turbulence dissipation time scale), the Coulomb-turbulence parameter (ratio of Coulomb 'terminal' speed to the turbulence dissipation velocity scale) and the settling parameter (the ratio of the gravitational terminal speed to the turbulence dissipation velocity scale). The theory is compared to measured RDFs for water particles in homogeneous, isotropic air turbulence. The RDFs are obtained from particle positions measured in three dimensions using digital holography. The measurements verify the general theoretical expression, consisting of a power law increase in particle clustering due to particle response to dissipative turbulent eddies, modulated by an exponential electrostatic interaction term. Both terms are modified as a result of the gravitational diffusion-like term, and the role of 'gravity' is explored by imposing a macroscopic uniform electric field to create an enhanced, effective gravity.

  2. Clustering of settling charged particles in turbulence: theory and experiments

    International Nuclear Information System (INIS)

    Atmospheric clouds, electrosprays and protoplanetary nebula (dusty plasma) contain electrically charged particles embedded in turbulent flows, often under the influence of an externally imposed, approximately uniform gravitational or electric force. We have developed a theoretical description of the dynamics of such systems of charged, sedimenting particles in turbulence, allowing radial distribution functions (RDFs) to be predicted for both monodisperse and bidisperse particle size distributions. The governing parameters are the particle Stokes number (particle inertial time scale relative to turbulence dissipation time scale), the Coulomb-turbulence parameter (ratio of Coulomb 'terminal' speed to the turbulence dissipation velocity scale) and the settling parameter (the ratio of the gravitational terminal speed to the turbulence dissipation velocity scale). The theory is compared to measured RDFs for water particles in homogeneous, isotropic air turbulence. The RDFs are obtained from particle positions measured in three dimensions using digital holography. The measurements verify the general theoretical expression, consisting of a power law increase in particle clustering due to particle response to dissipative turbulent eddies, modulated by an exponential electrostatic interaction term. Both terms are modified as a result of the gravitational diffusion-like term, and the role of 'gravity' is explored by imposing a macroscopic uniform electric field to create an enhanced, effective gravity.

  3. Galilean electrodynamics. Part 2. Charged particle force and conservation laws

    International Nuclear Information System (INIS)

    From the general formulae for the transformation of fields in Galilean electrodynamics there are derived the expression for the force acting on a charged particle and the equation of motion of a charged particle. Without any additional assumptions these equations are performed into the relativistic form, that is with the relativistic momentum and energy. Hence, in an elementary way, Einstein's formula of the equivalence of energy and mass results. Then the conservation laws of energy and momentum for the fields are derived. 3 refs. (author)

  4. A New Mechanism of Higgs Bosons in Producing Charge Particles

    DEFF Research Database (Denmark)

    Javadi, Hossein; Forouzbakhsh, Farshid

    2006-01-01

    A new production method of elementary particles by Higgs Bosons will be shown. But before that the structure of photon will be considered deeply, while a new definition of Higgs Boson about color-charges and color-magnet will be given for the first time.......A new production method of elementary particles by Higgs Bosons will be shown. But before that the structure of photon will be considered deeply, while a new definition of Higgs Boson about color-charges and color-magnet will be given for the first time....

  5. Charged-particle inclusive distributions from hadronic Z0 decays

    International Nuclear Information System (INIS)

    We have measured inclusive distributions for charged particles in hadronic decays of the Z boson. The variables chosen for study were the mean charged-particle multiplicity (left-angle nch right-angle), scaled momentum (x), and momenta transverse to the sphericity axes (p perpendicular in and p perpendicular out). The distributions have been corrected for detector effects and are compared with data from e+e- annihilation at lower energies and with the predictions of several QCD-based models. The data are in reasonable agreement with expectations. 12 refs., 2 figs

  6. Effect of neutron irradiation on charge collection efficiency in 4H-SiC Schottky diode

    International Nuclear Information System (INIS)

    The charge collection efficiency (CCE) in 4H-SiC Schottky diode is studied as a function of neutron fluence. The 4H-SiC diode was irradiated with fast neutrons of a critical assembly in Nuclear Physics and Chemistry Institute and CCE for 3.5 MeV alpha particles was then measured as a function of the applied reverse bias. It was found from our experiment that an increase of neutron fluence led to a decrease of CCE. In particular, CCE of the diode was less than 1.3% at zero bias after an irradiation at 8.26×1014 n/cm2. A generalized Hecht's equation was employed to analyze CCE in neutron irradiated 4H-SiC diode. The calculations nicely fit the CCE of 4H-SiC diode irradiated at different neutron fluences. According to the calculated results, the extracted electron μτ product (μτ)e and hole μτ product (μτ)h of the irradiated 4H-SiC diode are found to decrease by increasing the neutron fluence. -- Highlights: • An increase of neutron fluence led to a decrease of CCE in the irradiated 4H-SiC diode. • The experimental CCE of the neutron-irradiated 4H-SiC diode is nicely fitted using a generalized Hecht's equation. • The extracted electron/hole μτ product of the 4H-SiC diode decrease by increasing the neutron fluence

  7. The telegraph equation in charged particle transport

    Science.gov (United States)

    Gombosi, T. I.; Jokipii, J. R.; Kota, J.; Lorencz, K.; Williams, L. L.

    1993-01-01

    We present a new derivation of the telegraph equation which modifies its coefficients. First, an infinite order partial differential equation is obtained for the velocity space solid angle-averaged phase-space distribution of particles which underwent at least a few collisions. It is shown that, in the lowest order asymptotic expansion, this equation simplifies to the well-known diffusion equation. The second-order asymptotic expansion for isotropic small-angle scattering results in a modified telegraph equation with a signal propagation speed of v(5/11) exp 1/2 instead of the usual v/3 exp 1/2. Our derivation of a modified telegraph equation follows from an expansion of the Boltzmann equation in the relevant smallness parameters and not from a truncation of an eigenfunction expansion. This equation is consistent with causality. It is shown that, under steady state conditions in a convecting plasma, the telegraph equation may be regarded as a diffusion equation with a modified transport coefficient, which describes a combination of diffusion and cosmic-ray inertia.

  8. Charged Particle Monitor on the AstroSat mission

    CERN Document Server

    Rao, A R; Bhargava, Yash; Khanna, Rakesh; Hingar, M K; Kutty, A P K; Malkar, J P; Basak, Rupal; Sreekumar, S; Samuel, Essy; Priya, P; Vinod, P; Bhattacharya, D; Bhalerao, V; Vadawale, S V; Mithun, N P S; Pandiyan, R; Subbarao, K; Seetha, S; Sarma, K Suryanarayana

    2016-01-01

    Charged Particle Monitor (CPM) on-board the AstroSat satellite is an instrument designed to detect the flux of charged particles at the satellite location. A Cesium Iodide Thallium (CsI(Tl)) crystal is used with a Kapton window to detect protons with energies greater than 1 MeV. The ground calibration of CPM was done using gamma-rays from radioactive sources and protons from particle accelerators. Based on the ground calibration results, energy deposition above 1 MeV are accepted and particle counts are recorded. It is found that CPM counts are steady and the signal for the onset and exit of South Atlantic Anomaly (SAA) region are generated in a very reliable and stable manner.

  9. Universal behavior of charged particle production in heavy ion collisions

    Science.gov (United States)

    Phobos Collaboration; Steinberg, Peter A.; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Ballintijn, M.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2003-03-01

    The PHOBOS experiment at RHIC has measured the multiplicity of primary charged particles as a function of centrality and pseudorapidity in Au+Au collisions at sqrt(s_NN) = 19.6, 130 and 200 GeV. Two kinds of universal behavior are observed in charged particle production in heavy ion collisions. The first is that forward particle production, over a range of energies, follows a universal limiting curve with a non-trivial centrality dependence. The second arises from comparisons with pp/pbar-p and e+e- data. N_tot/(N_part/2) in nuclear collisions at high energy scales with sqrt(s) in a similar way as N_tot in e+e- collisions and has a very weak centrality dependence. This feature may be related to a reduction in the leading particle effect due to the multiple collisions suffered per participant in heavy ion collisions.

  10. Sausage mode of a pinched charged particle beam

    International Nuclear Information System (INIS)

    The axisymmetric oscillations of a self-pinched charged particle beam are analyzed using a dispersion relation derived from a 3/2 dimensional model. This calculation includes the effects of rounded profiles, finite conductivity, a steady return current, and phase mix damping among particle orbits. However, only the lowest order radial mode of distortion is treated, and this is done in an approximate fashion

  11. Construction of asymptotic fields for a charged particle

    OpenAIRE

    Greenberg, O. W.; Cowen, Steve

    2012-01-01

    Asymptotic fields do not exist in theories with massless particles and fields, because the vacuum matrix elements of products of the interacting fields in such theories do not have delta function or principal value singularities in momentum space. We remedy this problem by constructing a field for the charged particle that does have the required singularities in momentum space. We illustrate this construction in quantum electrodynamics (QED).

  12. A composite bolometer as a charged-particle spectrometer

    International Nuclear Information System (INIS)

    An improved version of a He-cooled composite diamond bolometer with a monolithic germanium thermistor, for use as a charged-particle spectrometer, is described. The performance of the bolometer was tested using 5-6 MeV α particles, and a full-width-at-half-maximum of 36 keV was obtained at 1.3 K. (U.K.)

  13. NANOSTRUCTURE PATTERNING UNDER ENERGETIC PARTICLE BEAM IRRADIATION

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lumin [Regents of the University of Michigan; Lu, Wei [Regents of the University of Michigan

    2013-01-31

    Energetic ion bombardment can lead to the development of complex and diverse nanostructures on or beneath the material surface through induced self-organization processes. These self-organized structures have received particular interest recently as promising candidates as simple, inexpensive, and large area patterns, whose optical, electronic and magnetic properties are different from those in the bulk materials [1-5]. Compared to the low mass efficiency production rate of lithographic methods, these self-organized approaches display new routes for the fabrication of nanostructures over large areas in a short processing time at the nanoscale, beyond the limits of lithography [1,4]. Although it is believed that surface nanostructure formation is based on the morphological instability of the sputtered surface, driven by a kinetic balance between roughening and smoothing actions [6,7], the fundamental mechanisms and experimental conditions for the formation of these nanostructures has still not been well established, the formation of the 3-D naopatterns beneath the irradiated surface especially needs more exploration. During the last funding period, we have focused our efforts on irradiation-induced nanostructures in a broad range of materials. These structures have been studied primarily through in situ electron microscopy during electron or ion irradiation. In particular, we have performed studies on 3-D void/bubble lattices (in metals and CaF2), embedded sponge-like porous structure with uniform nanofibers in irradiated semiconductors (Ge, GaSb, and InSb), 2-D highly ordered pattern of nanodroplets (on the surface of GaAs), hexagonally ordered nanoholes (on the surface of Ge), and 1-D highly ordered ripple and periodic arrays (of Cu nanoparticles) [3,8-11]. The amazing common feature in those nanopatterns is the uniformity of the size of nanoelements (nanoripples, nanodots, nanovoids or nanofibers) and the distance separating them. Our research focuses on the

  14. Microscopic analysis of irradiated AGR-1 coated particle fuel compacts

    Energy Technology Data Exchange (ETDEWEB)

    Scott Ploger; Paul Demkowicz; John Hunn; Robert Morris

    2012-10-01

    The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak burnup of 19.5% FIMA with no in-pile failures observed out of 3×105 total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Five compacts have been examined so far, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose between approximately 40-80 individual particles on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer-IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, over 800 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in approximately 23% of the particles, and these fractures often resulted in unconstrained kernel swelling into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer-IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only three particles, all in conjunction with IPyC-SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures, IPyC-SiC debonds, and SiC fractures.

  15. A practical alpha particle irradiator for studying internal alpha particle exposure.

    Science.gov (United States)

    Lee, Ki-Man; Lee, Ui-Seob; Kim, Eun-Hee

    2016-09-01

    An alpha particle irradiator has been built in the Radiation Bioengineering Laboratory at Seoul National University (SNU) to investigate the cellular responses to alpha emissions from radon and the progeny. This irradiator is designed to have the energy of alpha particles entering target cells similar to that of alpha emissions from the radon progeny Po-218 and Po-214 residing in the human respiratory tract. For the SNU alpha particle irradiator, an irradiation system is equipped with cell dishes of 4µm thick Mylar bottom and a special setup of cells on slide for gamma-H2AX assay. Dose calibration for the alpha particle irradiator was performed by dual approaches, detection and computer simulation, in consideration of the source-to-target distance (STD) and the size of a cell dish. The uniformity of dose among cells in a dish is achieved by keeping the STD and the size of cell dish in certain ranges. The performance of the SNU alpha particle irradiator has been proven to be reliable through the gamma-H2AX assay with the human lung epithelial cells irradiated. PMID:27475622

  16. Charged particles identification with a CsI(Tl) scintillator

    International Nuclear Information System (INIS)

    A CsI(Tl) scintillator with two light decay components is used to detect and identify p,d,t, 3He, α particles with a low energy threshold, Besides the addition of a thin plastic scintillator in front of the CsI(Tl) crystal allows charge identification for ions with Z up to 19

  17. Some peculiarity of element analysis using charged particle beams

    International Nuclear Information System (INIS)

    Multilayer structures, SiC -layers at Si substrate, have been analyzed by RBS, NR, ERD and PIXE methods using the charged particle beams from EG-5 Van de Graaff accelerator of JINR. The depth profiles of the based deposited layers were obtained for the multilayer structures

  18. Nondestructive diagnostics of charged particle beams in accelerators

    Science.gov (United States)

    Logachev, P. V.; Meshkov, O. I.; Starostenko, A. A.; Nikiforov, D. A.; Andrianov, A. V.; Maltseva, Yu. I.; Levichev, A. E.; Emanov, F. A.

    2016-03-01

    The basic techniques for nondestructive diagnostics and detection of losses of charged particle beams used in accelerator engineering are reviewed. The data provided may help choose the systems for diagnostics and detection of losses of beams and give a qualitative picture of the operation principles of such devices. Quantitative characteristics that define the limits of applicability of each diagnostic technique are outlined.

  19. Periodic interactions of charged particles with spatially localized fields

    International Nuclear Information System (INIS)

    We derive and analyze a generic mapping for the spatially periodic interaction of charged particles with localized, coherent electric fields. For such interactions stochastic motion exists in a bounded region of phase-space. Conditions are determined for which diffusion can describe the dynamics in such a bounded, stochastic phase-space. (orig.)

  20. Challenging the weak cosmic censorship conjecture with charged quantum particles

    International Nuclear Information System (INIS)

    Motivated by the recent attempts to violate the weak cosmic censorship conjecture for near-extreme black holes, we consider the possibility of overcharging a near-extreme Reissner-Nordstroem black hole by the quantum tunneling of charged particles. We consider the scattering of spin-0 and spin-(1/2) particles by the black hole in a unified framework and obtain analytically, for the first time, the pertinent reflection and transmission coefficients without any small charge approximation. Based on these results, we propose some gedanken experiments that could lead to the violation of the weak cosmic censorship conjecture due to the (classically forbidden) absorption of small energy charged particles by the black hole. As for the case of scattering in Kerr spacetimes, our results demonstrate explicitly that scalar fields are subject to (electrical) superradiance phenomenon, while spin-(1/2) fields are not. Superradiance impose some limitations on the gedanken experiments involving spin-0 fields, favoring, in this way, the mechanisms for creation of a naked singularity by the quantum tunneling of spin-(1/2) charged fermions. We also discuss the implications that vacuum polarization effects and quantum statistics might have on these gedanken experiments. In particular, we show that they are not enough to prevent the absorption of incident small energy particles and, consequently, the formation of a naked singularity.

  1. Some developments in neutron and charged particle dosimetry

    International Nuclear Information System (INIS)

    There is an increasing need for dosimetry of neutrons and charged particles. Increasing exposure levels are reported in the nuclear industry, deriving from more frequent in-service entries at commercial nuclear power plants, and from increased plant decommissioning and refurbishment activities. Another need stems from the compliance with requirements of the regulations and standards. The European Council directive 96/29 requires dosimetric precautions if the effective dose exceeds 1 mSv a-1. On average, aircrew members exceed this value. Further, there is a trend of increasing use of charged particles in radiotherapy. The present situation is that we have reasonably good photon dosemeters, but neutron and charged particle dosemeters are still in need of improvements. This work highlights some of the developments in this field. It is mainly concentrated on some developments in passive dosimetry, in particular thermally and optically stimulated luminescent detectors, indicating the direction of ongoing research. It shows that passive dosemeters are still a very active field. Active dosemeters will not be discussed with the exception of new developments in Micro-dosimetric measurements [new types of tissue equivalent proportional counters (TEPCs)]. The TEPC is unique in its ability to provide a simultaneous determination of neutron/charged particle/ gamma ray doses, or dose equivalents using a single detector. (authors)

  2. The Mathematics of Charged Particles interacting with Electromagnetic Fields

    DEFF Research Database (Denmark)

    Petersen, Kim

    In this thesis, we study the mathematics used to describe systems of charged quantum mechanical particles coupled with their classical self-generated electromagnetic field. We prove the existence of a unique local in time solution to the many-body Maxwell-Schrödinger initial value problem expressed...

  3. Bibliography of integral charged-particle nuclear data

    International Nuclear Information System (INIS)

    This publication is the first supplement to the archival edition of the National Nuclear Data Center's charged-particle bibliography. This supplement contains citations to all references scanned since March 15, 1980, and all corrections and additions to previous citations, and indexes all data received in the international exchanged format (EXFOR). The primary goal of the bibliography has been to satisfy the need expressed by the Nuclear Reaction Data Center Network for a concise and comprehensive bibliography of integral charged-particle cross section data and to provide an index of data exchanged among the members. As a result of a recommendation by the recent Workshop on Intense High Energy Neutron Source and Their Characteristics, we have also undertaken to expand the coverage of charged-particle-induced neutron-source reactions to include differential data. This supplement is divided into two sections, References and Isotope Production. The References section contains all references satisfying the criteria noted. The Isotope Production section contains an abbreviated reference line for all entries which contain information on a definite residual nucleus, on particle production, or on mass, charge, or isotopic distributions. Entries in the References section are sequentially numbered. These sequence numbers serve as a link between the two sections

  4. Thermodynamic model for bouncing charged particles inside a capacitor

    Science.gov (United States)

    Rezaeizadeh, Amin; Mameghani, Pooya

    2013-08-01

    We introduce an equation of state for a conducting particle inside a charged parallel-plate capacitor and show that it is similar to the equation of state for an ideal gas undergoing an adiabatic process. We describe a simple experiment that shows reasonable agreement with the theoretical model.

  5. Fusion reactivity graphs and tables for charged particle reactions

    International Nuclear Information System (INIS)

    Graphs and tables are presented on 31 light isotope fusion reaction parameters [, n, Q/sub +/, nQ/sub +/ (for n = 1020 fuel ion species/m3 and Q/sub +/ = energy release in charged particles)] in the kinetic temperature range 1 to 1000 keV

  6. Particle size and surface charge affect particle uptake by human dendritic cells in an in vitro model

    DEFF Research Database (Denmark)

    Foged, Camilla; Brodin, Birger; Frøkjær, Sven; Sundblad, Anne

    2005-01-01

    polystyrene particles was covalently modified with different polyaminoacids/proteins, yielding particles with varying surface charge. Uptake of 1 microm particles was greatly enhanced when particles displayed a positive surface charge. In general, the present findings establish that particle diameters of 0...

  7. Continuum of the spectra of emitted charged particles

    International Nuclear Information System (INIS)

    The continuous part of nuclear particle spectra situated between direct reactions and compound nuclear reactions is of importance due to its great yield. Because most reactions studied so far have only nucleons in the entrance or exit channel, respectively, the authors have measured charged particle spectra from complex particle induced reactions: deuterons, helions and alphas with bombarding energies up to 40 MeV/nucleon. From spectra measured at both forward and backward angles angle integrated spectra have been deduced which can be compared with the predictions of reaction models. (orig./AH)

  8. Guiding of charged particles through capillaries in insulating materials

    Science.gov (United States)

    Stolterfoht, Nikolaus; Yamazaki, Yasunori

    2016-04-01

    Studies of charged particle guiding through capillaries in insulating materials, performed during the last decade, are reviewed in a comprehensive manner. First, the principles of capillary guiding of slow highly charged ions are introduced describing the self-organized formation of charge patches. Basic quantities are defined, such as the guiding power characterizing a capillary. Challenges of the guiding experiments are pointed out. Then, experiments are described with emphasis on the guiding of highly charged ions in the keV energy range. Samples with an array of nanocapillaries as well as single macrocapillaries are treated. Emission profiles of transmitted ions are analyzed to establish scaling laws for the guiding angle, which quantifies the guiding power. Oscillations of the mean ion emission angle reveal the temporal dynamics of the charge patch formation. Next, experiments with ions of high (MeV) energies are focused on single tapered capillaries allowing for the production of a microbeam for various applications. Experiments concerning electrons are presented showing that apart from being elastically scattered these negative particles may enter into the capillary surface where they suffer energy losses. Finally, theoretical concepts of the capillary guiding are discussed. Simulations based on different charge transport methods clearly support the understanding of the guiding mechanisms. Altogether, capillary guiding involves several novel phenomena for which understanding have progressed far beyond their infancy.

  9. Response of mouse marrow colony forming units (CFU-S) to heavy charged particles

    International Nuclear Information System (INIS)

    A fundamental objective of the Bevalac Biomedical Program is to characterize biological responses in relation to the physical properties of heavy charged particles. Information collected with a variety of biological systems should contribute to the exploitation of the unique properties of heavy charged particles for radiotherapy and other medical applications. Relationships between RBE for CFU-S killing and LET were the first questions addressed in our studies. The procedure used was to harvest bone marrow from the femurs of animals within two hours after total-body irradiation, preparation of appropriate aliquots, and injection of marrow suspensions into animals that had received a supralethal dose of 60Co gamma radiation. Recipients of bone marrow transplants are sacrificed at 8 to 10 days, spleens excised and placed in an appropriate fixitive, and spleen colonies greater than 0.5 mm accounted with a dissecting microscope

  10. Charged-particle LET-spectra measurements aboard LDEF

    International Nuclear Information System (INIS)

    The linear energy transfer (LET) spectra of charged particles was measured in the 5 to 250 keV/micron (water) interval with CR-39 and in the 500 to 1500 keV/micron (water) interval with polycarbonate plastic nuclear track detectors (PNTDs) under different shielding depths in the P0006 experiment. The optimal processing conditions were determined for both PNTDs in relation to the relatively high track densities due to the long term exposure in space. The total track density was measured over the selected samples, and tracks in coincidence on the facing surfaces of two detector sheets were selected for measuring at the same position on each sheet. The short range (SR) and Galactic Cosmic Ray (GCR) components were measured separately with CR-39 PNTDs and the integral dose and dose rate spectra of charged particles were also determined. The high LET portion of the LET spectra was measured with polycarbonate PNTDs with high statistical accuracy. This is a unique result of this exposure due to the low flux of these types of particles for typical spaceflight durations. The directional dependence of the charged particles at the position of the P0006 experiment was also studied by four small side stacks which surrounded the main stack and by analyzing the dip angle and polar angle distributions of the measured SR and GCR particle tracks in the main stack

  11. Cosmic-Ray Generated Charged Particles for Nuclear Inspection

    International Nuclear Information System (INIS)

    Charged particles continuously rain down on the surface of the Earth. These charged particles primarily consist of muons and electrons. Muons are subatomic particles with the same charge as the electron, but with 200 times the mass. These particles are generated from interactions of primary cosmic-rays, primarily protons, with the upper atmosphere. Decision Sciences has implemented a tracking detector to measure the interactions of these particles with materials through which they pass: multiple Coulomb scattering and ionization energy loss and from these measurements is able to reconstruct a three-dimensional map of the density and atomic number of the materials in a scan volume. This map, combined with sensitive gamma detection capability of the tracking detector, enables the detection of nuclear and radiological materials that may be concealed in shielding, as well as discrimination of naturally occurring radioactive materials (NORM) from point sources that would be more associated with threats. Times to clear most non-threat cargo range from 30-60 seconds, with suspicious (heavy shielding or gamma emitting) scenes being held longer to confirm the presence of and identify nuclear or radiological materials. Extended scanning in this circumstance would typically take two to ten minutes. (author)

  12. Monitoring of Hadrontherapy Treatments by Means of Charged Particle Detection.

    Science.gov (United States)

    Muraro, Silvia; Battistoni, Giuseppe; Collamati, Francesco; De Lucia, Erika; Faccini, Riccardo; Ferroni, Fernando; Fiore, Salvatore; Frallicciardi, Paola; Marafini, Michela; Mattei, Ilaria; Morganti, Silvio; Paramatti, Riccardo; Piersanti, Luca; Pinci, Davide; Rucinski, Antoni; Russomando, Andrea; Sarti, Alessio; Sciubba, Adalberto; Solfaroli-Camillocci, Elena; Toppi, Marco; Traini, Giacomo; Voena, Cecilia; Patera, Vincenzo

    2016-01-01

    The interaction of the incoming beam radiation with the patient body in hadrontherapy treatments produces secondary charged and neutral particles, whose detection can be used for monitoring purposes and to perform an on-line check of beam particle range. In the context of ion-therapy with active scanning, charged particles are potentially attractive since they can be easily tracked with a high efficiency, in presence of a relatively low background contamination. In order to verify the possibility of exploiting this approach for in-beam monitoring in ion-therapy, and to guide the design of specific detectors, both simulations and experimental tests are being performed with ion beams impinging on simple homogeneous tissue-like targets (PMMA). From these studies, a resolution of the order of few millimeters on the single track has been proven to be sufficient to exploit charged particle tracking for monitoring purposes, preserving the precision achievable on longitudinal shape. The results obtained so far show that the measurement of charged particles can be successfully implemented in a technology capable of monitoring both the dose profile and the position of the Bragg peak inside the target and finally lead to the design of a novel profile detector. Crucial aspects to be considered are the detector positioning, to be optimized in order to maximize the available statistics, and the capability of accounting for the multiple scattering interactions undergone by the charged fragments along their exit path from the patient body. The experimental results collected up to now are also valuable for the validation of Monte Carlo simulation software tools and their implementation in Treatment Planning Software packages. PMID:27536555

  13. Monitoring of Hadrontherapy Treatments by Means of Charged Particle Detection

    Science.gov (United States)

    Muraro, Silvia; Battistoni, Giuseppe; Collamati, Francesco; De Lucia, Erika; Faccini, Riccardo; Ferroni, Fernando; Fiore, Salvatore; Frallicciardi, Paola; Marafini, Michela; Mattei, Ilaria; Morganti, Silvio; Paramatti, Riccardo; Piersanti, Luca; Pinci, Davide; Rucinski, Antoni; Russomando, Andrea; Sarti, Alessio; Sciubba, Adalberto; Solfaroli-Camillocci, Elena; Toppi, Marco; Traini, Giacomo; Voena, Cecilia; Patera, Vincenzo

    2016-01-01

    The interaction of the incoming beam radiation with the patient body in hadrontherapy treatments produces secondary charged and neutral particles, whose detection can be used for monitoring purposes and to perform an on-line check of beam particle range. In the context of ion-therapy with active scanning, charged particles are potentially attractive since they can be easily tracked with a high efficiency, in presence of a relatively low background contamination. In order to verify the possibility of exploiting this approach for in-beam monitoring in ion-therapy, and to guide the design of specific detectors, both simulations and experimental tests are being performed with ion beams impinging on simple homogeneous tissue-like targets (PMMA). From these studies, a resolution of the order of few millimeters on the single track has been proven to be sufficient to exploit charged particle tracking for monitoring purposes, preserving the precision achievable on longitudinal shape. The results obtained so far show that the measurement of charged particles can be successfully implemented in a technology capable of monitoring both the dose profile and the position of the Bragg peak inside the target and finally lead to the design of a novel profile detector. Crucial aspects to be considered are the detector positioning, to be optimized in order to maximize the available statistics, and the capability of accounting for the multiple scattering interactions undergone by the charged fragments along their exit path from the patient body. The experimental results collected up to now are also valuable for the validation of Monte Carlo simulation software tools and their implementation in Treatment Planning Software packages. PMID:27536555

  14. Change in surface of polymer materials upon irradiation of accelerated micro-particles

    Energy Technology Data Exchange (ETDEWEB)

    Kudo, Hisaaki [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan)]. E-mail: hkudo@utnl.jp; Tadokoro, Masashi [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan); Narita, Shintaro [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan); Matsuoka, Leo [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan); Muroya, Yusa [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan); Katsumura, Yosuke [Nuclear Engineering Research Laboratory, School of Engineering, University of Tokyo, 2-22 Shirakata-Shirane, Tokai, Ibaraki 319-1188 (Japan)

    2005-07-01

    As a new method of use of a particle accelerator (ionizing radiation generator), we irradiated accelerated micro-particles of silver (Ag) onto polymer materials such as polyimides, glass, ceramics and semi-conductors. The particles can be generated at a Van de Graaff electrostatic accelerator operating at 1-3 MV. The velocity was around 1-10 km/s, size of diameter was about 1-10 {mu}m and charge was about 1-2 {mu}C. We investigated the change in surface of materials upon irradiation, by using laser microscope, atomic force microscope and scanning electron microscope. Crater-shaped irradiation spots having limb structure were found, and their diameter and depth were evaluated, ranging in a few micrometers. The planar distribution of the projectile around the irradiation spot was examined with energy dispersive X-ray spectroscopy. Correlation between size of the irradiation spots and kinetic energy of the accelerated micro-particles was investigated, and compared with an empirical formula and molecular dynamics study. Numerical simulation dealing with dynamic behaviour of elastic structure was carried out based on SPH (Smoothed Particle Hydrodynamics) method, a kind of (virtual) particle method. The simulation also found that a crater-shaped spot having limb structure is formed upon collision of the accelerated projectile with the target-materials. The results of simulation were compared with the experimental observations. These experiment and simulation are important for the evaluation of damages and resistance of polymer materials used in the space, such as the thermal control material, and cover glass of solar cells etc., towards space debris and dusts. It would be complement the on-ground radiation resistant tests on the materials conducted by using electron and ion beam accelerators.

  15. Space charge distribution measurement methods and particle loaded insulating materials

    Energy Technology Data Exchange (ETDEWEB)

    Hole, S [Laboratoire des Instruments et Systemes d' Ile de France, Universite Pierre et Marie Curie-Paris6, 10 rue Vauquelin, 75005 Paris (France); Sylvestre, A [Laboratoire d' Electrostatique et des Materiaux Dielectriques, CNRS UMR5517, 25 avenue des Martyrs, BP 166, 38042 Grenoble cedex 9 (France); Lavallee, O Gallot [Laboratoire d' Etude Aerodynamiques, CNRS UMR6609, boulevard Marie et Pierre Curie, Teleport 2, BP 30179, 86962 Futuroscope, Chasseneuil (France); Guillermin, C [Schneider Electric Industries SAS, 22 rue Henry Tarze, 38000 Grenoble (France); Rain, P [Laboratoire d' Electrostatique et des Materiaux Dielectriques, CNRS UMR5517, 25 avenue des Martyrs, BP 166, 38042 Grenoble cedex 9 (France); Rowe, S [Schneider Electric Industries SAS, 22 rue Henry Tarze, 38000 Grenoble (France)

    2006-03-07

    In this paper the authors discuss the effects of particles (fillers) mixed in a composite polymer on the space charge measurement techniques. The origin of particle-induced spurious signals is determined and silica filled epoxy resin is analysed using the laser-induced-pressure-pulse (LIPP) method, the pulsed-electro-acoustic (PEA) method and the laser-induced-thermal-pulse (LITP) method. A spurious signal identified as the consequence of a piezoelectric effect of some silica particles is visible for all the method. Moreover, space charges are clearly detected at the epoxy/silica interface after a 10 kV mm{sup -1} poling at room temperature for 2 h.

  16. Brownian Dynamics of charged particles in a constant magnetic field

    CERN Document Server

    Hou, L J; Piel, A; Shukla, P K

    2009-01-01

    Numerical algorithms are proposed for simulating the Brownian dynamics of charged particles in an external magnetic field, taking into account the Brownian motion of charged particles, damping effect and the effect of magnetic field self-consistently. Performance of these algorithms is tested in terms of their accuracy and long-time stability by using a three-dimensional Brownian oscillator model with constant magnetic field. Step-by-step recipes for implementing these algorithms are given in detail. It is expected that these algorithms can be directly used to study particle dynamics in various dispersed systems in the presence of a magnetic field, including polymer solutions, colloidal suspensions and, particularly complex (dusty) plasmas. The proposed algorithms can also be used as thermostat in the usual molecular dynamics simulation in the presence of magnetic field.

  17. Charged Q-balls and boson stars and dynamics of charged test particles

    CERN Document Server

    Brihaye, Yves; Hartmann, Betti

    2014-01-01

    We construct electrically charged Q-balls and boson stars in a model with a scalar self-interaction potential resulting from gauge mediated supersymmetry breaking. We discuss the properties of these solutions in detail and emphasize the differences to the uncharged case. We observe that $Q$-balls can only be constructed up to a maximal value of the charge of the scalar field, while for boson stars the interplay between the attractive gravitational force and the repulsive electromagnetic force determines their behaviour. We also study the motion of charged, massive test particles in the space-time of boson stars. We find that in contrast to charged black holes the motion of charged test particles in charged boson star space-times is planar, but that the presence of the scalar field plays a crucial r\\^ole for the qualitative features of the trajectories. Applications of this test particle motion can be made in the study of extreme-mass ratio inspirals (EMRIs) as well as astrophysical plasmas relevant e.g. in th...

  18. A State of Art Report on Technology Development of Irradiation Test and Irradiation Behavior for High Temperature Gas-cooled Reactor Coated Particle Fuel

    International Nuclear Information System (INIS)

    Coated particle fuel, Irradiation test of coated particle fuel in foreign countries are introduced in this report. Also reviewed are status of the study on irradiation performance of coated particle fuel, irradiation facilities for irradiation test of coated particle fuel in foreign countries and current status of irradiation test plan of coated particle fuel in foreign countries' research reactor, and preliminary feasibility is analyzed the irradiation test of coated particle fuel in HANARO

  19. Effects of dispersive wave modes on charged particles transport

    CERN Document Server

    Schreiner, Cedric

    2015-01-01

    The transport of charged particles in the heliosphere and the interstellar medium is governed by the interaction of particles and magnetic irregularities. For the transport of protons a rather simple model using a linear Alfv\\'en wave spectrum which follows the Kolmogorov distribution usually yields good results. Even magnetostatic spectra may be used. For the case of electron transport, particles will resonate with the high-k end of the spectrum. Here the magnetic fluctuations do not follow the linear dispersion relation, but the kinetic regime kicks in. We will discuss the interaction of fluctuations of dispersive waves in the kinetic regime using a particle-in-cell code. Especially the scattering of particles following the idea of Lange et al. (2013) and its application to PiC codes will be discussed. The effect of the dispersive regime on the electron transport will be discussed in detail.

  20. Effect of Charge, Size and Temperature on Stability of Charged Colloidal Nano Particles

    Institute of Scientific and Technical Information of China (English)

    A. Golchoobi; A. Khosravi; H. Modarress; A Ahmadzadeh

    2012-01-01

    Molecular simulation of charged colloidal suspension is performed in NVT canonical ensemble using Monte Carlo method and primitive model.The well-known Derjaguin-Landau-Verwey-Overbeek theory is applied to account for effective interactions between particles.Effect of temperature,valance of micro-ions and the size of colloidal particles on the phase stability of the solution is investigated.The results indicate that the suspension is more stable at higher temperatures.On the other hand,for a more stable suspension to exist,lower microion valance is favorable.For micro-ions of higher charge the number of aggregates and the number of particle in each of aggregate on average is higher.However for the best of our results larger colloidal particle are less stable.Comparing the results with theoretical formula considering the influence of surface curvature shows qualitative consistency.

  1. Microstructural characterization of second phase irradiated Zircaloy-4 particles

    International Nuclear Information System (INIS)

    X-ray diffraction diagrams of neutron irradiated Zircaloy-4 were obtained at the LNLS with the aim to obtain bulk information about the amorphization process in which the Zircaloy-4 second phase particles (SPPs) undergoes due to neutron irradiation. Owing to the low concentration of the SPPs in the alloy (∼0.4 V %), no data regarding to the bulk were obtained until now. The synchrotron experiences allowed to detect five of the more intense lines of the phase C 14 (SPPs structure) in unirradiated Zircaloy-4: (110) θ, (103) θ, (112) θ, (201) θ and (004) θ in the 34 degrees ≤ θ2≤45 degrees Bragg angle range and others of minor intensity. The diagrams of the samples irradiated at moderate doses (1020n/cm2) show these lines even in the as received samples. In contrast, none of these lines are observed for high fluence samples (∼1022neutrons/cm2). In addition, in similar high fluence samples annealed 24 h or 72 h at 600 C degrees the intensity rises just at the 2q range where the C 14 lines were observed, showing a wide peak. That peak is interpreted as a result of the superposition of unresolved diffraction lines corresponding to the Zircaloy SPPs which are in a reconstitution process of crystallization. Analytical Electron Microscopy techniques were used, in order to study the effects on the Zircaloy-4 SPPs and compared with samples of the same material without irradiation. Spots in SAD patterns of non irradiated SPPS, evidences the presence of a C 14 structure, but in irradiated SSP SAD patterns evidences the beginning of an amorphization process. Another important feature to point out is the different Fe / Cr ratio presented in both irradiated and non irradiated SSPs. In non irradiated precipitates the Fe / Cr ratio is approximately 1.5, while in irradiated precipitates the Fe / Cr ratio becomes near 1.0. (author)

  2. Isospin Effect of Charged Particle Multiplicity in Intermediate Energy Heavy Ion Collisions

    Institute of Scientific and Technical Information of China (English)

    HuRongjiang; WuHeyu; JinGenming; ZhuYongtai; DuanLimin; XiaoZhigang; WangHongwei

    2003-01-01

    The dependences of He and intermediate mass fragments (IMF) production rates in the reactions 55 MeV/u 40Ar+58,64 Ni on the isospin, impact parameter and primary excitation energy of the reaction nuclear system were studied by using the 4π charged particle multi-detector array system (MUDAL). For the mentioned two reaction systems, the measured He particle contribution in the total charged particle multiplicity increases with increasing the total charged particle multiplicity but for the contribution of IMFs in the total charged particle multiplicity increases with increasing the total charged particle multiplicity at lower total charged particle multiplicities, and latter on it drops down with further increasing of the total charged particle multiplicities (see Fig.l). The experimental results of these two reaction systems with the same nuclear charge indicate that the contribution of He and IMFs in the total charged particle multiplicities are obviously isospin dependent.

  3. Charge transfer inefficiency in the pre- and post-irradiated Swept Charge Device CCD236

    International Nuclear Information System (INIS)

    This paper describes the mapping of spectral response of an e2v technologies Swept Charge Device (SCD) CCD236 pre and post irradiation with a 10 MeV equivalent proton fluence of 5.0 × 108 protons cm−2. The CCD236 is a large area (4.4 cm2) X-ray detector which will be used in India's Chandrayaan-2 Large Soft X-ray Spectrometer (CLASS) and China's Hard X-ray Modulation Telescope (HXMT). To enable the suppression of surface dark current, clocking is performed continuously resulting in a linear readout. As such the flat field illumination used to measure any change in spectral response over a conventional Charge-Coupled Devices (CCDs) is not possible. An alternative masking technique has been used to expose pinpoint regions of the device to Mn-Kα and Mn-Kβ X-rays, enabling a local map of spectral response to be built up over the device. This novel approach allows for an estimation of the Charge Transfer Inefficiency (CTI) of the device to be made by allowing the creation of a CTI scatter plot similar to that typically observed in conventional CCDs

  4. Persistent oxidative stress in human neural stem cells exposed to low fluences of charged particles

    Directory of Open Access Journals (Sweden)

    Janet E. Baulch

    2015-08-01

    Full Text Available Exposure to the space radiation environment poses risks for a range of deleterious health effects due to the unique types of radiation encountered. Galactic cosmic rays are comprised of a spectrum of highly energetic nuclei that deposit densely ionizing tracks of damage along the particle trajectory. These tracks are distinct from those generated by the more sparsely ionizing terrestrial radiations, and define the geometric distribution of the complex cellular damage that results when charged particles traverse the tissues of the body. The exquisite radiosensitivity of multipotent neural stem and progenitor cells found within the neurogenic regions of the brain predispose the central nervous system to elevated risks for radiation induced sequelae. Here we show that human neural stem cells (hNSC exposed to different charged particles at space relevant fluences exhibit significant and persistent oxidative stress. Radiation induced oxidative stress was found to be most dependent on total dose rather than on the linear energy transfer of the incident particle. The use of redox sensitive fluorogenic dyes possessing relative specificity for hydroxyl radicals, peroxynitrite, nitric oxide (NO and mitochondrial superoxide confirmed that most irradiation paradigms elevated reactive oxygen and nitrogen species (ROS and RNS, respectively in hNSC over a 1 week interval following exposure. Nitric oxide synthase (NOS was not the major source of elevated nitric oxides, as the use of NOS inhibitors had little effect on NO dependent fluorescence. Our data provide extensive evidence for the capability of low doses of charged particles to elicit marked changes in the metabolic profile of irradiated hNSC. Radiation induced changes in redox state may render the brain more susceptible to the development of neurocognitive deficits that could affect an astronaut’s ability to perform complex tasks during extended missions in deep space.

  5. Strange particle production in neutrino-neon charged current interactions

    International Nuclear Information System (INIS)

    Neutral strange particle production in charged-current muon-neutrino interactions have been studied in the Fermilab 15-foot neon bubble chamber. Associated production is expected to be the major source of strange particles in charged-current neutrino interactions. σ-neutral and ξ-minus production by neutrinos was observed. The dependence on various leptonic and hadronic variables is investigated. A fit to single and associated production of s, s/anti-s, and c quarks is described based on the number of single and double strange particle production events. Inclusive neutral strange particle decays (V0) production rates as a fraction of all charged-current events are measured and are tabulated. The λ/K ratio is found to be 0.39 +- 0.04 and the fraction of λ coming from σ-neutral is (16 +- 5)%. The single- and double V0 production was used to determine the associated s anti-s production rate and single s-quark production rate. 13 refs., 7 figs., 3 tabs

  6. Charged Particle Therapy Steps Into the Clinical Environment

    Science.gov (United States)

    Haberer, Th.

    Beams of heavy charged particles like protons or carbon ions represent the ideal tool for the treatment of deep-seated, inoperable and radioresistant tumors. For more than 4 decades research with beams of charged particles has been performed. In total more than 40000 patients have been treated, mostly using protons being delivered by accelerators that were designed for basic research centers. In Berkeley, USA heavier particles like helium or neon ions were used to conduct clinical trials until 1992. Based on that somewhat limited technological standard and triggered by the promising results from Berkeley the first dedicated charged particle facilities were constructed. In order to maximally exploit the advantageous physical and radiobiological characteristics of these beams enormous effort was put into developing dynamic beam delivery techniques and tailoring the capabilities of the accelerators, the planning systems and the quality assurance procedures and equipment to the requirements resulting from these new treatment modalities. Active beam delivery systems integrated in rotating gantries, if necessary, will allow the production of superior dose distributions that precisely follow the medical prescription. The technological progress being made during the last 10 years defines the state of the art of the upcoming next-generation facilities for the clinical environment in Europe and Japan.

  7. DART: a simulation code for charged particle beams

    Energy Technology Data Exchange (ETDEWEB)

    White, R.C.; Barr, W.L.; Moir, R.W.

    1988-05-16

    This paper presents a recently modified verion of the 2-D DART code designed to simulate the behavior of a beam of charged particles whose paths are affected by electric and magnetic fields. This code was originally used to design laboratory-scale and full-scale beam direct converters. Since then, its utility has been expanded to allow more general applications. The simulation technique includes space charge, secondary electron effects, and neutral gas ionization. Calculations of electrode placement and energy conversion efficiency are described. Basic operation procedures are given including sample input files and output. 7 refs., 18 figs.

  8. DART: a simulation code for charged particle beams

    International Nuclear Information System (INIS)

    This paper presents a recently modified verion of the 2-D DART code designed to simulate the behavior of a beam of charged particles whose paths are affected by electric and magnetic fields. This code was originally used to design laboratory-scale and full-scale beam direct converters. Since then, its utility has been expanded to allow more general applications. The simulation technique includes space charge, secondary electron effects, and neutral gas ionization. Calculations of electrode placement and energy conversion efficiency are described. Basic operation procedures are given including sample input files and output. 7 refs., 18 figs

  9. Signal and charge collection efficiency of n-in-p strip detectors after mixed irradiation to HL-LHC fluences

    Energy Technology Data Exchange (ETDEWEB)

    Kuehn, Susanne, E-mail: susanne.kuehn@cern.ch [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Barber, Thomas [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Casse, Gianluigi; Dervan, Paul [Department of Physics, University of Liverpool, The Oliver Lodge Laboratory, Oxford Street L69 7ZE (United Kingdom); Driewer, Adrian [Fraunhofer Institute for Microelectronic Circuits and Systems, Finkenstr. 61, 47057 Duisburg (Germany); Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany); Forshaw, Dean; Huse, Torkjell [Department of Physics, University of Liverpool, The Oliver Lodge Laboratory, Oxford Street L69 7ZE (United Kingdom); Jakobs, Karl; Parzefall, Ulrich [Institute of Physics, University of Freiburg, Hermann-Herder-Str. 3, 79104 Freiburg (Germany)

    2013-12-01

    For the year 2020, an upgrade of the LHC with a factor ten increase in luminosity is planned. The resulting severe radiation doses for the ATLAS tracker demand extremely radiation tolerant detectors. In this study six planar n-in-p strip sensors produced by Hamamatsu Photonics were irradiated in consecutive irradiation steps with pions of 280 Mev/c, protons of 25 Mev/c and reactor neutrons resulting in a combined fluence of up to 3×10{sup 15} 1 MeV neutron equivalent particles per square centimeter (n{sub eq}/cm{sup 2}). This particle composition and fluence corresponds to the qualification limit specified by the ATLAS experiment for the outer pixel layers (assuming an integrated luminosity of 3000 fb{sup −1}). The 320μm thick devices are investigated using electrons from a {sup 90}Sr source. After each irradiation step both charge collection efficiency and noise measurements have been performed using the ALIBAVA readout system, which is based on analogue Beetle ASICs clocked at 40 MHz. Measurements of the signal and signal-to-noise ratio of detectors will be given after the sensors were exposed to radiation that both in fluence and composition are corresponding to the expectations for the HL-LHC trackers. Conclusions will be drawn on their operation in the ATLAS inner detector upgrade. -- Highlights: •Charge collection measurements of n-in-p strip detectors irradiated up to 3E15 n{sub eq}/cm{sup 2}. •Signal reduced from 25 k electrons before irradiation to 9–11 k electrons at 600 V bias. •Signal-to-noise ratio measured above 10 at 600 V after irradiation with pions, protons and neutrons. •N-in-p strip detectors functional for doses in inner strip layers of ATLAS in the HL-LHC. •Results agreeing to results after single particle irradiation.

  10. Detection of charged particles through a photodiode: design and analysis

    International Nuclear Information System (INIS)

    This project develops and construct an charge particle detector mean a pin photodiode array, design and analysis using a silicon pin Fotodiodo that generally is used to detect visible light, its good efficiency, size compact and reduced cost specifically allows to its use in the radiation monitoring and alpha particle detection. Here, so much, appears the design of the system of detection like its characterization for alpha particles where one is reported as alpha energy resolution and detection efficiency. The equipment used in the development of work consists of alpha particle a triple source composed of Am-241, Pu-239 and Cm-244 with 5,55 KBq as total activity, Maestro 32 software made by ORTEC, a multi-channel card Triumph from ORTEC and one low activity electroplated uranium sample. (Author)

  11. Modelling die filling with charged particles using DEM/CFD

    Institute of Scientific and Technical Information of China (English)

    Emmanuel Nkem Nwose; Chunlei Pei; Chuan-Yu Wu

    2012-01-01

    The effects of electrostatic charge on powder flow behaviour during die filling in a vacuum and in air were analysed using a coupled discrete element method and computational fluid dynamics (DEM/CFD) code,in which long range electrostatic interactions were implemented.The present 2D simulations revealed that both electrostatic charge and the presence of air can affect the powder flow behaviour during die filling.It was found that the electrostatic charge inhibited the flow of powders into the die and induced a loose packing structure.At the same filling speed,increasing the electrostatic charge led to a decrease in the fill ratio which quantifies the volumetric occupancy of powder in the die.In addition,increasing the shoe speed caused a further decrease in the fill ratio,which was characterised using the concept of critical filling speed.When the electrostatic charge was low,the air/particle interaction was strong so that a lower critical filling speed was obtained for die filling in air than in a vacuum.With high electrostatic charge,the electrostatic interactions became dominant.Consequently,similar fill ratio and critical filling speed were obtained for die filling in air and in a vacuum.

  12. Charge particle accelerator - a brief review, future challenges and applications

    International Nuclear Information System (INIS)

    Charged particle accelerators are important tools to investigate hitherto inaccessible problems in various fields of science. The interaction of charged particles with materials reveals structural information at very small scale (-16 cm). Accelerator based equipments viz. scanning electron microscope (SEM), transmission electron microscope (TEM) and focused ion beam (FIB) machines are extensively being used to explore new possibilities in nanotechnology. Many experiments in nuclear and particle physics examine the fundamental laws of physics by colliding a high-energy beam of particles, such as electrons or protons, with a fixed target or with another beam of particles. Modern light sources, which are capable of producing high-energy photons such as X-rays, operate by 'bending' the path of electrons in an accelerator with magnets to generate radiation. State-of-the-art cancer treatment facilities utilize high-energy proton and heavier ion beams to treat inoperable tumors. The man made sun, International Thermonuclear Experimental Reactor (ITER), will utilize 1 MeV, 40 A neutral proton beams for additional heating of the plasma. A roadmap for developing accelerator driven systems (ADS) in India was prepared in 2001 and involves development of a 1 GeV, 30 mA proton linear accelerator. Due to potential applications, developing high energy accelerators worldwide is a challenge for the community. New acceleration schemes to make accelerator size compact have been realized. In the present talk, various types of accelerators, accelerator based programs worldwide and new acceleration scheme of charge particles will be discussed. The low energy ion beam facility (LEIBF) at IUAC and a few experimental results arising from this facility will be presented. Finally, I will touch some applications, particularly in nanotechnology, where accelerators are making a big impact. (author)

  13. Growth and instability of charged dislocation loops under irradiation in ceramic materials

    CERN Document Server

    Ryazanov, A I; Kinoshita, C; Klaptsov, A V

    2002-01-01

    We have investigated the physical mechanisms of the growth and stability of charged dislocation loops in ceramic materials with very strong different mass of atoms (stabilized cubic zirconia) under different energies and types of irradiation conditions: 100-1000 keV electrons, 100 keV He sup + and 300 keV O sup + ions. The anomalous formation of extended defect clusters (charged dislocation loops) has been observed by TEM under electron irradiation subsequent to ion irradiation. It is demonstrated that very strong strain field (contrast) near charged dislocation loops is formed. The dislocation loops grow up to a critical size and after then become unstable. The instability of the charged dislocation loop leads to the multiplication of dislocation loops and the formation of dislocation network near the charged dislocation loops. A theoretical model is suggested for the explanation of the growth and stability of the charged dislocation loop, taking the charge state of point defects. The calculated distribution...

  14. RPL in alpha particle irradiated Ag+-doped phosphate glass

    International Nuclear Information System (INIS)

    The objective of this study is to investigate the emission mechanism of radiophotoluminescence (RPL) in the Ag+-doped phosphate glass (glass dosimeter), which is now used as individual radiation dosimeter, because the emission mechanism of RPL in glass dosimeter has been not fully understood. We have investigated the assignments and characteristics of the X-ray induced color centers in the Ag+-doped phosphate glass up to now (Miyamoto et al., 2010). Optical properties such as optical absorption spectra related with alpha-particles and X-rays irradiation were measured for commercially available glass dosimeter. In this study optical properties such as optical absorption spectrum as a function of alpha-particles and X-rays irradiation were measured for commercially available glass dosimeter. Comparison of the RPL in Ag+-doped phosphate glass irradiated with alpha-particles and X-rays is discussed. - Highlights: • A Yellow and blue emission are included in the RPL of Ag+-doped phosphate glass. • The ratio of yellow and blue emission was different between alpha and X-ray irradiation. • RPL emission intensity increased in an atmosphere below room temperature

  15. RESONANCE BROADENING AND HEATING OF CHARGED PARTICLES IN MAGNETOHYDRODYNAMIC TURBULENCE

    International Nuclear Information System (INIS)

    The heating, acceleration, and pitch-angle scattering of charged particles by magnetohydrodynamic (MHD) turbulence are important in a wide range of astrophysical environments, including the solar wind, accreting black holes, and galaxy clusters. We simulate the interaction of high-gyrofrequency test particles with fully dynamical simulations of subsonic MHD turbulence, focusing on the parameter regime with β ∼ 1, where β is the ratio of gas to magnetic pressure. We use the simulation results to calibrate analytical expressions for test particle velocity-space diffusion coefficients and provide simple fits that can be used in other work. The test particle velocity diffusion in our simulations is due to a combination of two processes: interactions between particles and magnetic compressions in the turbulence (as in linear transit-time damping; TTD) and what we refer to as Fermi Type-B (FTB) interactions, in which charged particles moving on field lines may be thought of as beads sliding along moving wires. We show that test particle heating rates are consistent with a TTD resonance that is broadened according to a decorrelation prescription that is Gaussian in time (but inconsistent with Lorentzian broadening due to an exponential decorrelation function, a prescription widely used in the literature). TTD dominates the heating for vs >> vA (e.g., electrons), where vs is the thermal speed of species s and vA is the Alfvén speed, while FTB dominates for vs A (e.g., minor ions). Proton heating rates for β ∼ 1 are comparable to the turbulent cascade rate. Finally, we show that velocity diffusion of collisionless, large gyrofrequency particles due to large-scale MHD turbulence does not produce a power-law distribution function.

  16. Irradiated Microsphere Gamma Analyzer for Examination of Particle Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Paul A. Demkowicz; Various

    2014-06-01

    Fabrication of the first series of fuel compacts for the current US tristructural isotropic (TRISO) coated particle fuel development and qualification effort was completed at Oak Ridge National Laboratory (ORNL) in 2006. In November of 2009, after almost 3 years and 620 effective full power days of irradiation in the Advanced Test Reactor at Idaho National Laboratory (INL), the first Advanced Gas Reactor irradiation test (AGR-1) was concluded. Compacts were irradiated at a calculated timeaveraged, volume-averaged temperature of 955–1136°C to a burnup ranging from 11.2–19.5% fissions per initial metal atom and a total fast fluence of 2.2–4.3·1025 n/m2 [1]. No indication of fission product release from TRISO coating failure was observed during the irradiation test, based on real-time monitoring of gaseous fission products. Post-irradiation examination (PIE) and hightemperature safety testing of the compacts has been in progress at both ORNL and INL since 2010, and have revealed small releases of a limited subset of fission products (such as silver, cesium, and europium). Past experience has shown that some elements can be released from TRISO particles when a defect forms in the SiC layer, even when one or more pyrocarbon layers remain intact and retain the gaseous fission products. Some volatile elements can also be released by diffusion through an intact SiC layer during safety testing if temperatures are high enough and the duration is long enough. In order to understand and quantify the release of certain radioactive fission products, it is sometimes necessary to individually examine each of the more than 4000 coated particles in a given compact. The Advanced Irradiated Microsphere Gamma Analyzer (Advanced- IMGA) was designed to perform this task in a remote hot cell environment. This paper describes the Advanced- IMGA equipment and examination process and gives results for a typical full compact evaluation.

  17. Emission of ions and charged soot particles by aircraft engines

    Directory of Open Access Journals (Sweden)

    A. Sorokin

    2003-01-01

    Full Text Available In this article, a model which examines the formation and evolution of chemiions in an aircraft engine is proposed. This model which includes chemiionisation, electron thermo-emission, electron attachment to soot particles and to neutral molecules, electron-ion and ion-ion recombination, ion-soot interaction, allows the determination of the ion concentration at the exit of the combustor and at the nozzle exit of the engine. It also allows the determination of the charge of the soot particles. For the engine considered, the upper limit for the ion emission index EIi is of the order of (2-5 x1016 ions/kg-fuel if ion-soot interactions are ignored and the introduction of ion-soot interactions lead about to a 50% reduction. The results also show that most of the soot particles are either positively or negatively charged, the remaining neutral particles representing approximately 20% of the total particles. A comparison of the model results with the available ground-based experimental data obtained on the ATTAS research aircraft engines during the SULFUR experiments (Schumann, 2002 shows an excellent agreement.

  18. The Motion of a Pair of Charged Particles

    CERN Document Server

    Franklin, J

    2013-01-01

    We re-visit the problem of two (oppositely) charged particles interacting electromagnetically in one dimension with retarded potentials and no radiation reaction. The specific quantitative result of interest is the time it takes for the particles to fall in towards one another. Starting with the non-relativistic form, we answer this question while adding layers of complexity until we arrive at the full relativistic delay differential equation that governs this problem. That case can be solved using the Synge method, which we describe and discuss.

  19. The Search for Fractional Charge Elementary Particles and Very Massive Particles in Bulk Matter

    CERN Document Server

    Perl, Martin Lewis; Kim, P C; Lee, E R; Lee, I T; Loomba, D; Perl, Martin L.; Halyo, Valerie; Kim, Peter C.; Lee, Eric R.; Lee, Irwin T.; Loomba, Dinesh

    2000-01-01

    We describe our ongoing work on, and future plans for, searches in bulk matter for fractional charge elementary particles and very massive elementary particles. Our primary interest is in searching for such particles that may have been produced in the early universe and may be found in the more primeval matter available in the solar system: meteorites, material from the moon's surface, and certain types of ancient terrestrial rocks. In the future we are interested in examining material brought back by sample return probes from asteroids. We will describe our experimental methods that are based on new modifications of the Millikan liquid drop technique and modern technology: micromachining, CCD cameras, and desktop computers. Extensions of our experimental methods and technology allow searches for very massive charged particles in primeval matter; particles with masses greater than 10**13 GeV. In the first such searches carried out on earth there will be uncertainties in the mass search range. Therefore we wil...

  20. Charged point particles with magnetic moment in general relativity

    International Nuclear Information System (INIS)

    Halbwachs Lagrangean formalism for the theory of charged point particles with spin (g = 2) is generalized and formulated in General Relativity for particles of arbitrary charge and magnetic moment. Equations are obtained, both corresponding to Frenkel's condition Ssub(μν)Xsup(ν) = 0 and to Nakano's condition Ssub(μν)Psup(ν) = 0. With the later condition the exact equations are highly coupled and non linear. When linearized in the electromagnetic and gravitational fields they coincide with de Groot-Suttorp equations for vanishing gravitational fields and with Dixon-Wald equations in the absence of electromagnetic field. The equations corresponding to Frenkel's condition, when linearized in Ssub(μν), coincide with Papapetrou's and Frenkel's equations in the corresponding limits

  1. Electro-Optical Detection of Charged Particle Beams

    CERN Document Server

    Semertzidis, Y K; Kowalski, L A; Kraus, D E; Larsen, R C; Lazarus, D M; Magurno, B; Srinivasan-Rao, T; Tsang, Thomas; Usack, V

    1999-01-01

    We have made the first observation of a charged particle beam by means of its electro-optical effect on the propagation of laser light in a birefringent crystal at the Brookhaven National Laboratory Accelerator Test Facility. Polarized infrared light was coupled to a LiNbO3 crystal through a polarization maintaining fiber of 4 micron diameter. An electron beam in 10ps bunches of 1mm diameter was scanned across the crystal. The modulation of the laser light during passage of the electron beam was observed using a photodiode with 45GHz bandwidth. The fastest rise time measured, 120ps, was made in the single shot mode and was limited by the bandwidth of the oscilloscope and the associated electronics. Both polarization dependent and polarization independent effects were observed. This technology holds promise of greatly improved spatial and temporal resolution of charged particle beams.

  2. 3D Simulations of Space Charge Effects in Particle Beams

    International Nuclear Information System (INIS)

    For the first time, it is possible to calculate the complicated three-dimensional proton accelerator structures at the Paul Scherrer Institut (PSI). Under consideration are external and self effects, arising from guiding and space-charge forces. This thesis has as its theme the design, implementation and validation of a tracking program for charged particles in accelerator structures. This work form part of the discipline of Computational Science and Engineering (CSE), more specifically in computational accelerator modelling. The physical model is based on the collisionless Vlasov-Maxwell theory, justified by the low density (∼ 109 protons/cm3) of the beam and of the residual gas. The probability of large angle scattering between the protons and the residual gas is then sufficiently low, as can be estimated by considering the mean free path and the total distance a particle travels in the accelerator structure. (author)

  3. 3D Simulations of Space Charge Effects in Particle Beams

    Energy Technology Data Exchange (ETDEWEB)

    Adelmann, A

    2002-10-01

    For the first time, it is possible to calculate the complicated three-dimensional proton accelerator structures at the Paul Scherrer Institut (PSI). Under consideration are external and self effects, arising from guiding and space-charge forces. This thesis has as its theme the design, implementation and validation of a tracking program for charged particles in accelerator structures. This work form part of the discipline of Computational Science and Engineering (CSE), more specifically in computational accelerator modelling. The physical model is based on the collisionless Vlasov-Maxwell theory, justified by the low density ({approx} 10{sup 9} protons/cm{sup 3}) of the beam and of the residual gas. The probability of large angle scattering between the protons and the residual gas is then sufficiently low, as can be estimated by considering the mean free path and the total distance a particle travels in the accelerator structure. (author)

  4. Charged particle induced prompt nuclear reaction and its applications

    International Nuclear Information System (INIS)

    Charged particle induced prompt nuclear reaction analysis (PNR) not only can analyze the content and concentration of elements in sample sensitively and accurately, but also can measure the distributions of elements with depth in surface and near surface layer. And the method is very simple, rapid and nondestructive, and has good depth resolution. So the PNR is very widely used in many modern science and technique field such as solid state physics, surface physics, electrochemistry, metallurgy and material science and so on. This paper deals with the principle, method and the features of the nuclear reaction analysis induced by charged particle. Especially, the distribution analysis of impurities in sample with depth and the improvement of the depth resolution are discussed in detail. Some actual examples of its application are given

  5. Production of carbon monoxide by charged particle deposition.

    Science.gov (United States)

    Green, A. E. S.; Sawada, T.; Edgar, B. C.; Uman, M. A.

    1973-01-01

    Recent studies of electron energy deposition in CO2 and CO based upon a large set of electron impact cross sections are utilized to estimate the telluric CO directly produced by various charged-particle deposition mechanisms. The mechanisms considered are (1) lightning, (2) cloud coronal discharges, (3) background radioactivity, (4) natural electrostatic discharges, (5) photoelectrons in the ionosphere, (6) auroral electrons, (7) auroral protons, (8) cosmic rays, and (9) solar wind. 'Ball park' estimates of the global CO production by each of these mechanisms are given. Apart from mechanisms 1, 2, and 5, all CO production mechanisms are estimated to be small compared to artificial sources. If, as appears to be the case, the hot oxygen atoms and ions and other atomic species immediately produced by these three charged-particle deposition mechanisms react rapidly with CO2 to produce CO, these mechanisms can readily lead to CO production levels in the multimegaton-per-year range.

  6. Effect of collisions on dust particle charging via particle-in-cell Monte-Carlo collision

    Science.gov (United States)

    Rovagnati, B.; Davoudabadi, M.; Lapenta, G.; Mashayek, F.

    2007-10-01

    In this paper, the effect of collisions on the charging and shielding of a single dust particle immersed in an infinite plasma is studied. A Monte-Carlo collision (MCC) algorithm is implemented in the particle-in-cell DEMOCRITUS code to account for the collisional phenomena which are typical of dusty plasmas in plasma processing, namely, electron-neutral elastic scattering, ion-neutral elastic scattering, and ion-neutral charge exchange. Both small and large dust particle radii, as compared to the characteristic Debye lengths, are considered. The trends of the steady-state dust particle potential at increasing collisionality are presented and discussed. The ions and electron energy distributions at various locations and at increasing collisionality in the case of large particle radius are shown and compared to their local Maxwellians. The ion-neutral charge-exchange collision is found to be by far the most important collisional phenomenon. For small particle radius, collisional effects are found to be important also at low level of collisionality, as more ions are collected by the dust particle due to the destruction of trapped ion orbits. For large particle radius, the major collisional effect is observed to take place in proximity of the presheath. Finally, the species energy distribution functions are found to approach their local Maxwellians at increasing collisionality.

  7. Transport of Charged Particles: Entropy Production and Maximum Dissipation Principle

    OpenAIRE

    Hsieh, Chia-Yu; Hyon, YunKyong; Lee, Hijin; Lin, Tai-Chia; Liu, Chun

    2014-01-01

    In order to describe the dynamics of crowded ions (charged particles), we use an energetic variation approach to derive a modified Poisson-Nernst-Planck (PNP) system which includes an extra dissipation due to the effective velocity differences between ion species. Such a system is more complicated than the original PNP system but with the same equilibrium states. Using Schauder's fixed-point theorem, we develop a local existence theorem of classical solutions for the modified PNP system. Diff...

  8. Charged particle detectors made from thin layers of amorphous silicon

    International Nuclear Information System (INIS)

    A series of experiments was conducted to determine the feasibility of using hydrogenated amorphous silicon (α-Si:H) as solid state thin film charged particle detectors. 241Am alphas were successfully detected with α-Si:H devices. The measurements and results of these experiments are presented. The problems encountered and changes in the fabrication of the detectors that may improve the performance are discussed

  9. Laser focusing of high-energy charged-particle beams

    International Nuclear Information System (INIS)

    It is shown that laser focusing of high-energy charged-particle beams using the inverse Cherenkov effect is well suited for applications with large linear colliders. Very high gradient (>0.5 MG/cm) lenses result that can be added sequentially without AG cancellation. These lenses are swell understood, have small geometric aberrations, and offer the possibility of correlating phase and energy aberrations to produce an achromatic final focus

  10. Electrostatic energy analyzers for high energy charged particle beams

    International Nuclear Information System (INIS)

    The electrostatic energy analyzers for high energy charged particle beams emitted from extended large-size objects as well as from remote point sources are proposed. Results of the analytical trajectory solutions in ideal cylindrical field provide focusing characteristics for both configurations. The instruments possess of simple compact design, based on an ideal cylindrical field with entrance window arranged in the end-boundary between electrodes and can be used for measurements in space technologies, plasma and nuclear physics

  11. Multidimensional analysis of charged particles from neutron-induced reactions

    International Nuclear Information System (INIS)

    A survey is given of the most recent experimental results obtained using twin gridded ionization chamber constructed at Obninsk, Russia. Peculiarities of (n,α) and (n,f) reactions investigated are discussed. The detailed description ol the method of charge particles spectrometry is presented. Selected results on fission fragment characteristics are discussed more in detail. Present experiments and instrumental developments are focussed on correlations between fragment masses, energies and emission angles and on fine structures in fragment parameter distributions. (author)

  12. Dynamical structure functions for charged particle bilayers and superlattices

    International Nuclear Information System (INIS)

    A modified Feynman construction with a zero-frequency central peak is used to model the dynamical structure functions for layered charged particle systems. This construction recognizes the affinity between layered and multicomponent systems. It also guarantees the simultaneous satisfaction of all three frequency-moment sum rules. The frequencies and spectral weights of the long-wavelength collective excitations and the strength of the diffusive central peak are calculated for arbitrary degeneracy

  13. Measurement of Forward-Backward Charged Particle Correlations with ALICE

    DEFF Research Database (Denmark)

    Søgaard, Carsten

    (NBI). In order for this calibration system to work, a special trigger interface was implemented. The developed and tested firmware for the FPGA (Field-Programmable Gate Array) will be presented. Part II is the presentation of the analysis - a study of, so-called, forward-backward correlations....... The correlations between charged particles, produced in proton-proton collisions at vs=900 GeV and vs=7 TeV over a wide range in pseudoradidity (-3.5

  14. Charged-Particle Multiplicity in Proton-Proton Collisions

    OpenAIRE

    Grosse-Oetringhaus, Jan Fiete; Reygers, Klaus

    2009-01-01

    This article summarizes and critically reviews measurements of charged-particle multiplicity distributions and pseudorapidity densities in p+p(pbar) collisions between sqrt(s) = 23.6 GeV and sqrt(s) = 1.8 TeV. Related theoretical concepts are briefly introduced. Moments of multiplicity distributions are presented as a function of sqrt(s). Feynman scaling, KNO scaling, as well as the description of multiplicity distributions with a single negative binomial distribution and with combinations of...

  15. Optimizing interactive program for charged particle transport system design

    International Nuclear Information System (INIS)

    A computer program for charged particle transport system design is described. The program is written in the BASIC language and allows one to make calculations in dialogue with the computer. The BASTRA program permits to get output information both in digital and in graphical forms. The method for optimization is described, that allows one to put 10 limitation on beam parameters in arbitrary places of the transport system. The program can be adapted on every computer having the BASIC language in its software

  16. Neutron-Induced Charged Particle Studies at LANSCE

    Science.gov (United States)

    Lee, Hye Young; Haight, Robert C.

    2014-09-01

    Direct measurements on neutron-induced charged particle reactions are of interest for nuclear astrophysics and applied nuclear energy. LANSCE (Los Alamos Neutron Science Center) produces neutrons in energy of thermal to several hundreds MeV. There has been an effort at LANSCE to upgrade neutron-induced charged particle detection technique, which follows on (n,z) measurements made previously here and will have improved capabilities including larger solid angles, higher efficiency, and better signal to background ratios. For studying cross sections of low-energy neutron induced alpha reactions, Frisch-gridded ionization chamber is designed with segmented anodes for improving signal-to-noise ratio near reaction thresholds. Since double-differential cross sections on (n,p) and (n,a) reactions up to tens of MeV provide important information on deducing nuclear level density, the ionization chamber will be coupled with silicon strip detectors (DSSD) in order to stop energetic charged particles. In this paper, we will present the status of this development including the progress on detector design, calibrations and Monte Carlo simulations. This work is funded by the US Department of Energy - Los Alamos National Security, LLC under Contract DE-AC52-06NA25396.

  17. Electromagnetic radiation of charged particles in stochastic motion

    Energy Technology Data Exchange (ETDEWEB)

    Harko, Tiberiu [Babes-Bolyai University, Department of Physics, Cluj-Napoca (Romania); University College London, Department of Mathematics, London (United Kingdom); Mocanu, Gabriela [Astronomical Institute of the Romanian Academy, Cluj-Napoca (Romania)

    2016-03-15

    The study of the Brownian motion of a charged particle in electric and magnetic fields has many important applications in plasma and heavy ions physics, as well as in astrophysics. In the present paper we consider the electromagnetic radiation properties of a charged non-relativistic particle in the presence of electric and magnetic fields, of an exterior non-electromagnetic potential, and of a friction and stochastic force, respectively. We describe the motion of the charged particle by a Langevin and generalized Langevin type stochastic differential equation. We investigate in detail the cases of the Brownian motion with or without memory in a constant electric field, in the presence of an external harmonic potential, and of a constant magnetic field. In all cases the corresponding Langevin equations are solved numerically, and a full description of the spectrum of the emitted radiation and of the physical properties of the motion is obtained. The power spectral density of the emitted power is also obtained for each case, and, for all considered oscillating systems, it shows the presence of peaks, corresponding to certain intervals of the frequency. (orig.)

  18. Microsparks Generated by Charged Particles in Dielectric Liquids

    Science.gov (United States)

    Geiger, Robert

    2012-10-01

    The electrodynamics of charged particles in dielectric liquids have been described by several authors [1,2]. As a charged particle approaches an electrode of opposite charge the local electric field eventually exceeds the dielectric strength of the liquid and a microspark is generated. These plasmas can be very small, about type of discharge can provide a simple means of generating non-thermal plasmas in dielectric liquids, such as oils or other hydrocarbons, which can be used to chemically process the liquids. Such a technology may lead to a highly efficient method of heavy oil upgrading which can be easily scaled. In order to understand the plasma properties optical emission spectroscopy is carried out for various hydrocarbons and voltage-current characteristics are used to determine the energy cost for this process. [4pt] [1] Melcher, James R. Continuum Electromechanics. Cambridge, MA: MIT Press, 1981.[0pt] [2] Jones, Thomas B. Electromechanics of Particles. Cambridge University Press 1995.[0pt] [3] Staack, D., Fridman, A., Gutsol, A., Gogotsi, Y. and Friedman, G. 2008, Angew. Chem., Int. Ed. 47, 8020.

  19. Study of latent and etched tracks by a charged particle transmission technique

    CERN Document Server

    Vacik, J; Hnatowicz, V; Fink, D; Kobayashi, Y; Hirata, K; Apel, P Y; Strauss, P

    1999-01-01

    A recently suggested technique for non-destructive investigation of inhomogeneities in thin objects, which is based on the measurement of the energy spectra of charged particles transmitted through the object, is used for the study of thermal annealing of 10-20 mu m thick polyethylene terephtalate, polypropylene and polycarbonate foils irradiated with 1-10 MeV/amu heavy ions. At elevated temperature a foil linear contraction is observed on pristine and irradiated material. Also the foil roughness increases with increasing temperature. On the same foils with etched pores 0.5-1.0 mu m in diameter, the thermal annealing results in gradual closing of the pores up to about 30% of their initial diameter at the temperatures of 150-175 deg. C. At higher temperatures the pore diameter increases and achieves its initial value.

  20. Effects of target size on the comparison of photon and charged particle dose distributions

    International Nuclear Information System (INIS)

    The work presented here is part of an ongoing project to quantify and evaluate the differences in the use of different radiation types and irradiation geometries in radiosurgery. We are examining dose distributions for photons using the ''Gamma Knife'' and the linear accelerator arc methods, as well as different species of charged particles from protons to neon ions. A number of different factors need to be studied to accurately compare the different modalities such as target size, shape and location, the irradiation geometry, and biological response. This presentation focuses on target size, which has a large effect on the dose distributions in normal tissue surrounding the lesion. This work concentrates on dose distributions found in radiosurgery, as opposed to those usually found in radiotherapy. 5 refs., 2 figs

  1. The dynamics of charged particles in turbulent astrophysical plasmas

    Science.gov (United States)

    Dung, Rudiger; Petrosian, Vahe

    1994-01-01

    We consider the resonant interaction of energetic charged particles and transverse plasma wave propagating parallel and/or antiparallel to the uniform magnetic field B(sub 0) in an underlying background plasma of density n. The coupling of the plasma waves and the energetic particles will be controlled by the ratio n/(the absolute value of B(sub 0)(exp 2). A variation of this ratio leads to a strong variation of the dynamics of the energetic particles. By taking into account the whole transverse plasma branch for the resonant interaction we discuss the influence of the background plasma density, the background magnetic field, the cross helicity, and the magnetic helicities on the dynamics of charged particles in astrophysical plasmas. It is shown that low-energy electrons can be accelerated efficiently by the higher electromagnetic waves and short-wavelength whistlers for low values of the ratio n/(the absolute value of B(sub 0)(exp 2), which means for low values of the ratio of plasma frequency to gyrofrequency.

  2. Predicted angular distribution of fast charged particles with ionization

    International Nuclear Information System (INIS)

    Moliere theory of angular distribution for fast charged particles is improved to take into account ionization loss, by using Kamata-Nishimura formulation of the theory. Decrease of the particle energy along the passage hence increase of the screening angle brings a slight different results from those derived by Moliere-Bethe formulation for fixed energies. The present results are reduced to the same Moliere distribution with modified values of the expansion parameter and the unit of Moliere angle. Properties of the new distribution and differences from the traditional one are discussed. Angular distributions of particles penetrating through the mixed or compound substances are also investigated both under the relativistic and the nonrelativistic conditions, together with the Kamata-Nishimura constants characterizing their formulation. (author)

  3. Irradiation behaviour of coated fuel particles for the fissile/fertile particle system

    International Nuclear Information System (INIS)

    The cross evaluation of 30 irradiation experiments which were carried out in the last ten years in order to test fuel particles for the separate use of high enriched uranium in fissile particles and thorium in fertile particles, led to the following results: An oxide-based fissile/fertile particle system (UO2 fissile kernel/ThO2 fertile kernel) can be used as well as the American carbide/oxide particle system (UC2 fissile kernel/ThO2 fertile kernel) under the operation conditions of a high temperature reactor with spherical fuel elements. The swelling of fissile kernels as a consequence of fission gas pores is much more pronounced in UO2 than in UC2 fissile kernels but the buffer layer copes with the swelling without any problems. Ceramic kernel additives (e.g. Al2O3)as well as carbon additives proved not to be suitable because they deteriorate the mechanical properties of the fissile kernels. Kernel migration in a temperature gradient ('amoeba effect') is observed during irradiation of UO2 fissile particles but this does not cause any coating failure. The amoeba effect is suppressed completely by 10% UC2 additives to the UO2 kernel. The silicon carbide interlayer is absolutely necessary for an efficient retention of the solid fission products and has also proved successfully for fertile particles. A measurable fraction of defective particle coatings was not observed before exceeding the target values of burnup and fast neutron fluence. The irradiation-induced dimensional changes of the graphite matrix are independent of the fuel volume loading and have no influence on the irradiation behaviour of the embedded fissile and fertile particles. (orig./IHOE)

  4. Theory of intense beams of charged particles optics of charged particle analyzers

    CERN Document Server

    Hawkes, Peter W

    2011-01-01

    Advances in Imaging and Electron Physics merges two long-running serials--Advances in Electronics and Electron Physics and Advances in Optical and Electron Microscopy. This series features extended articles on the physics of electron devices (especially semiconductor devices), particle optics at high and low energies, microlithography, image science and digital image processing, electromagnetic wave propagation, electron microscopy, and the computing methods used in all these domains. * Contributions from leading international scholars and industry experts * Discusses hot topic areas and pr

  5. Effects of solids with charged particles fluxes. Modern status of simulation investigation

    International Nuclear Information System (INIS)

    The data are presented on investigations carried out in Kharkov Institute of Physics and Technology (KIPT) during last years in the field of simulation and studies of radiation damage in materials with the use of accelerators of charged particles. Using irradiation with charged particle beams one could reproduce and examine practically all the known radiation effects and investigate physical nature of these effects in more details under well-controlled conditions. Simulation experiments together with results of reactor investigation contribute much to radiation physics phenomena, radiation and ion-beam technologies as well as to creation of low-activated materials with good radiation resistance. The advantages and disadvantages of simulation experiments in comparison with reactor tests are discussed. The using of new types of accelerators (of two and three beams) and of modern methods of research allows minimize the restrictions and disadvantages in the using of results of simulation experiments caused by low depth of damaged layer. Modern status of using accelerators demand by such main tasks: understanding of radiation damage mechanism of nuclear materials; achievement of better knowledge of the nature of point defects and interaction between them; set up the correlation between radiation-induced defects, structure phase evolution and material degradation mechanism; investigation of stability of systems which have nanoscale features. It is especially important for development and prediction of radiation behavior at high irradiation doses of nano-precipitates in ODS steels, which are the most pronounce materials for of next generation. (authors)

  6. The present status of the LLNL Evaluated Charged Particle Library (ECPL)

    International Nuclear Information System (INIS)

    The present report is written with two purposes in mind: to summarize the charged-particle reactions that presently exist in Evaluated Charge Particle Library; and to list all of the low-Z charged-particle reactions for which data exist in the Livermore experimental data compilation. 2 tabs

  7. The use of charge-pumping for characterizing irradiated power MOSFETs

    International Nuclear Information System (INIS)

    A charge-pumping technique is proposed for characterizing radiation-induced interface traps in vertical power MOSFETs. An original setup allowing measurements on these 3-contact devices is presented. The first experimental results before and after irradiation are discussed

  8. The Stability of the Vacuum Polarization Surrounding a Charged Particle

    CERN Document Server

    Himpsel, F J

    2015-01-01

    The internal stability of the electron has been debated for a century at both the classical and the quantum level. Recently, a local force density balance was established for the 1s electron in the H atom, based on the energy-momentum tensor of the classical Dirac field. This methodology is now extended to quantum fields by considering the force densities acting on the vacuum polarization induced by a point charge. Such a model is applicable to any charged particle at large distances, since the only vestige of its internal structure is the electric Coulomb field together with the vacuum polarization induced by it. While the polarization charge density is attracted to the point charge, it is kept from collapsing by repulsive forces due to confinement and degeneracy. It is shown analytically that the corresponding force densities are balanced for every filled shell of mj states at a given angular momentum j. The force densities are then summed over all single-electron states in the Dirac sea and renormalized by...

  9. Study of a large acceptance charged particle detector

    International Nuclear Information System (INIS)

    We investigated basic characteristics of a new detector system, which has been designed to be used for nuclear data measurements. The detector has a large acceptance to cover a wide range of charged particle energies. The detector consists of crystal detectors and plastic scintillators. In this detector, energy measurements are carried out by adopting the pulse-height method for low-energy particles and for high-energy particles the time of flight (TOF) technique. The low-energy detector (crystals) plays also as a degrader for high-energy particles. One of important issues is the non-linearity of scintillation output for heavy ions of crystal detectors. The other issue is the deviation of a particle trajectory due to the multiple-scattering in the detector material. In the present study, we measured the scintillation output of detectors and the multiple-scattering effect on the TOF detection efficiency. Experiments were carried out at National Inst. of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba (NIRS-HIMAC) for a crystal detector system by using protons and Ar ions. Finally, the scintillation nonlinearity has been determined. As for the multiple-scattering effect, we found that both of simulations, GEANT4 and PHITS tend to underestimate. (author)

  10. Time-dependent charge distributions in polymer films under electron beam irradiation

    International Nuclear Information System (INIS)

    The time-dependent charge distribution in polymer film under electron beam irradiation is studied by both experiment and numerical simulation. In the experiment, the distribution is measured with the piezoinduced pressure wave propagation method. In the simulation, the initial charge distribution is obtained by the Monte Carlo method of electron scattering, and the charge drift in the specimen is simulated by taking into account the Poisson equation, the charge continuity equation, Ohm's law, and the radiation-induced conductivity. The results obtained show that the negative charge deposited in the polymer film, whose top and bottom surfaces are grounded, drifts toward both grounded electrodes and that twin peaks appear in the charge distribution. The radiation-induced conductivity plays an important role in determining the charge distribution in the polymer films under electron beam irradiation

  11. Moving Charged Particles in Lattice Boltzmann-Based Electrokinetics

    CERN Document Server

    Kuron, Michael; Schornbaum, Florian; Bauer, Martin; Godenschwager, Christian; Holm, Christian; de Graaf, Joost

    2016-01-01

    The motion of ionic solutes and charged particles under the influence of an electric field and the ensuing hydrodynamic flow of the underlying solvent is ubiquitous in aqueous colloidal suspensions. The physics of such systems is described by a coupled set of differential equations, along with boundary conditions, collectively referred to as the electrokinetic equations. Capuani et al. [J. Chem. Phys. 121, 973 (2004)] introduced a lattice-based method for solving this system of equations, which builds upon the lattice Boltzmann (LB) algorithm for the simulation of hydrodynamic flow and exploits computational locality. However, thus far, a description of how to incorporate moving boundary conditions, which are needed to simulate moving colloids, into the Capuani scheme has been lacking. In this paper, we detail how to introduce such moving boundaries, based on an analogue to the moving boundary method for the pure LB solver. The key ingredients in our method are mass and charge conservation for the solute spec...

  12. Charging and coagulation of radioactive and nonradioactive particles in the atmosphere

    Science.gov (United States)

    Kim, Yong-ha; Yiacoumi, Sotira; Nenes, Athanasios; Tsouris, Costas

    2016-03-01

    Charging and coagulation influence one another and impact the particle charge and size distributions in the atmosphere. However, few investigations to date have focused on the coagulation kinetics of atmospheric particles accumulating charge. This study presents three approaches to include mutual effects of charging and coagulation on the microphysical evolution of atmospheric particles such as radioactive particles. The first approach employs ion balance, charge balance, and a bivariate population balance model (PBM) to comprehensively calculate both charge accumulation and coagulation rates of particles. The second approach involves a much simpler description of charging, and uses a monovariate PBM and subsequent effects of charge on particle coagulation. The third approach is further simplified assuming that particles instantaneously reach their steady-state charge distributions. It is found that compared to the other two approaches, the first approach can accurately predict time-dependent changes in the size and charge distributions of particles over a wide size range covering from the free molecule to continuum regimes. The other two approaches can reliably predict both charge accumulation and coagulation rates for particles larger than about 0.04 micrometers and atmospherically relevant conditions. These approaches are applied to investigate coagulation kinetics of particles accumulating charge in a radioactive neutralizer, the urban atmosphere, and an atmospheric system containing radioactive particles. Limitations of the approaches are discussed.

  13. The all particle method: Coupled neutron, photon, electron, charged particle Monte Carlo calculations

    International Nuclear Information System (INIS)

    At the present time a Monte Carlo transport computer code is being designed and implemented at Lawrence Livermore National Laboratory to include the transport of: neutrons, photons, electrons and light charged particles as well as the coupling between all species of particles, e.g., photon induced electron emission. Since this code is being designed to handle all particles this approach is called the ''All Particle Method''. The code is designed as a test bed code to include as many different methods as possible (e.g., electron single or multiple scattering) and will be data driven to minimize the number of methods and models ''hard wired'' into the code. This approach will allow changes in the Livermore nuclear and atomic data bases, used to described the interaction and production of particles, to be used to directly control the execution of the program. In addition this approach will allow the code to be used at various levels of complexity to balance computer running time against the accuracy requirements of specific applications. This paper describes the current design philosophy and status of the code. Since the treatment of neutrons and photons used by the All Particle Method code is more or less conventional, emphasis in this paper is placed on the treatment of electron, and to a lesser degree charged particle, transport. An example is presented in order to illustrate an application in which the ability to accurately transport electrons is important. 21 refs., 1 fig

  14. Parallel Multiphysics Simulations of Charged Particles in Microfluidic Flows

    CERN Document Server

    Bartuschat, Dominik

    2014-01-01

    The article describes parallel multiphysics simulations of charged particles in microfluidic flows with the waLBerla framework. To this end, three physical effects are coupled: rigid body dynamics, fluid flow modelled by a lattice Boltzmann algorithm, and electric potentials represented by a finite volume discretisation. For solving the finite volume discretisation for the electrostatic forces, a cell-centered multigrid algorithm is developed that conforms to the lattice Boltzmann meshes and the parallel communication structure of waLBerla. The new functionality is validated with suitable benchmark scenarios. Additionally, the parallel scaling and the numerical efficiency of the algorithms are analysed on an advanced supercomputer.

  15. Charged particle scattering on two infinite cylindrical solenoids

    International Nuclear Information System (INIS)

    Charged particle scattering on two infinitely parallel cylindrical solenoids with similar by value and inverse by the sign magnetic fields is considered. Scattering amplitude is calculated in the 1st Born and high energy approximations. In both cases the differential cross section is nonsingular and the integral one - finite. Specific examples demonstrating that in one and the same multi-connection space under nontrivial vector-potentials and unambigous wave functions Aharonov-Bohm (AB) effect can exist but it can be absent as well. It is shown that an alternative AB effect interpretation as scattering in magnetic field leakages meets sufficient difficulties

  16. Motion of charged particles in a knotted electromagnetic field

    Energy Technology Data Exchange (ETDEWEB)

    Arrayas, M; Trueba, J L, E-mail: joseluis.trueba@urjc.e [Area de Electromagnetismo, Universidad Rey Juan Carlos, Camino del Molino s/n, 28943 Fuenlabrada, Madrid (Spain)

    2010-06-11

    In this paper we consider the classical relativistic motion of charged particles in a knotted electromagnetic field. After reviewing how to construct electromagnetic knots from maps between the three-sphere and the two-sphere, we introduce a mean quadratic radius of the energy density distribution in order to study some properties of this field. We study the classical relativistic motion of electrons in the electromagnetic field of the Hopf map, and compute their trajectories. It is observed that these electrons initially at rest are strongly accelerated by the electromagnetic force, becoming ultrarelativistic in a period of time that depends on the knot energy and size.

  17. A technique to improve crystal channeling efficiency of charged particles

    CERN Document Server

    Tikhomirov, V V

    2007-01-01

    It is shown that a narrow plane cut near the crystal surface considerably increases the probability of capture into the stable channeling motion of positively charged particles entering a crystal at angles smaller than a quarter of the critical channeling angle with respect to the crystal planes. At smallest incidence angles the capture probability reaches 99 percent. A pair of crystals bent in orthogonal planes and provided with the cuts allows to reach a 99.9 percent efficiency of single-pass deflection of a proton beam with an ultra small divergence. Conditions necessary for efficient single-pass deflection of protons from the LHC beam halo are also discussed.

  18. Fabrication and testing of prototype preamplifier for charged particle detector

    International Nuclear Information System (INIS)

    Development of a 4π charged particle array is one of the major activities under the superconducting cyclotron utilization project. The forward part of the array will consist of 24 telescopes, each will have three elements Si (strip) ΔE, Si(strip) E and CsI(Ti) E. Each ΔE strip will have 16 channels whereas E-strip will have 16 vertical and 16 horizontal channels. The large number of Si channels mandated the development of low-cost, high-density preamplifiers. A variety of circuits have been tested and some prototype preamplifiers have been fabricated. The performance of a prototype preamplifier has been reported

  19. Charged particle and magnetic field research in space

    Science.gov (United States)

    1972-01-01

    Research completed and in progress is described, related publications and reports are listed, and abstracts of papers and talks on results of the research are given. The charged particle research centered on OGO-5 and OGO-6 electron spectrometer data, and theoretical radiation belt studies. Work on the ATS-1 magnetometer project included development of production data reduction programs, development of spectral analysis procedures, and scientific studies of ULF waves at synchronous orbit. The magnetic fields research also included work on the Mariner project and theoretical studies on the solar wind.

  20. Charged particle induced energy dispersive X-ray analysis

    International Nuclear Information System (INIS)

    This review article deals with the X-ray emission induced by heavy, charged particles and the use of this process as an analytical method (PIXE). The physical processes involved, X-ray emission and the various reactions contributing to the background, are described in some detail. The sensitivity is calculated theoretically and the results compared with practical experience. A discussion is given on how the sensitivity can be optimized. The experimental arrangements are described and the various technical problems discussed. The analytical procedure, especially the sample preparation, is described in considerable detail. A number of typical practical applications are discussed. (author)

  1. Nonlinear Stability Theorem for High-Intensity Charged Particle Beams

    International Nuclear Information System (INIS)

    Global conservation constraints based on the nonlinear Vlasov-Maxwell equations are used to derive a three-dimensional kinetic stability theorem for an intense non-neutral ion beam (or charge bunch) propagating with average axial velocity vb=const . It is shown that a sufficient condition for linear and nonlinear stability for perturbations with arbitrary polarization is that the equilibrium distribution be a monotonically decreasing function of the single-particle energy H' in the beam frame, i.e., ∂feq(H') /∂H'≤0 . copyright 1998 The American Physical Society

  2. Cataractogenic effects of heavy charged particles in mice

    International Nuclear Information System (INIS)

    The effects of heavy charged particles on the crystalline lens of the eye of mice are important because this tissue has proven susceptible to other forms of high-LET radiation. This report summarizes the results currently available from a prospectively designed study to explore the LET dependence of the cataractogenic process. The present results are consistent with a high cataractogenic effect at 100 keV/μm, because plateau argon 40 ions, with an LET in this range, produce higher average cataracts scores at 9, 11 and 13 months than do carbon 12 or neon 20 ions. In the electron micrographs, significant changes were observed from the controls

  3. Charged Particle Multiplicities in Deep Inelastic Scattering at HERA

    CERN Document Server

    Aïd, S; Andreev, V; Andrieu, B; Appuhn, R D; Babaev, A; Ban, Y; Baranov, P S; Barrelet, E; Barschke, R; Bartel, Wulfrin; Barth, Monique; Bassler, U; Beck, H P; Behrend, H J; Belousov, A; Berger, C; Bernardi, G; Bertrand-Coremans, G H; Besançon, M; Beyer, R; Biddulph, P; Bispham, P; Bizot, J C; Blobel, Volker; Borras, K; Botterweck, F; Boudry, V; Braemer, A; Braunschweig, W; Brisson, V; Bruel, P; Bruncko, Dusan; Brune, C R; Buchholz, R; Buniatian, A Yu; Burke, S; Burton, M; Bähr, J; Büngener, L; Bürger, J; Büsser, F W; Calvet, D; Campbell, A J; Carli, T; Charlet, M; Chechelnitskii, S; Chernyshov, V; Clarke, D; Clegg, A B; Clerbaux, B; Cocks, S P; Contreras, J G; Cormack, C; Coughlan, J A; Courau, A; Cousinou, M C; Cozzika, G; Criegee, L; Cussans, D G; Cvach, J; Dagoret, S; Dainton, J B; Dau, W D; Daum, K; David, M; Davis, C L; De Wolf, E A; Delcourt, B; Di Nezza, P; Dirkmann, M; Dixon, P; Dlugosz, W; Dollfus, C; Dowell, John D; Dreis, H B; Droutskoi, A; Duhm, H; Dünger, O; Ebert, J; Ebert, T R; Eckerlin, G; Efremenko, V; Egli, S; Eichler, R; Eisele, Franz; Eisenhandler, Eric F; Ellison, R J; Elsen, E E; Erdmann, M; Erdmann, W; Evrard, E; Fahr, A B; Favart, L; Fedotov, A; Feeken, D; Felst, R; Feltesse, Joel; Ferencei, J; Ferrarotto, F; Flamm, K; Fleischer, M; Flieser, M; Flügge, G; Fomenko, A; Fominykh, B A; Formánek, J; Foster, J M; Franke, G; Fretwurst, E; Gabathuler, Erwin; Gabathuler, K; Gaede, F; Garvey, J; Gayler, J; Gebauer, M; Genzel, H; Gerhards, R; Glazov, A; Goerlach, U; Gogitidze, N; Goldberg, M; Goldner, D; Golec-Biernat, Krzysztof J; González-Pineiro, B; Gorelov, I V; Grab, C; Greenshaw, T J; Griffiths, R K; Grindhammer, G; Gruber, A; Gruber, C; Grässler, Herbert; Grässler, R; Görlich, L; Haack, J; Hadig, T; Haidt, Dieter; Hajduk, L; Hampel, M; Haynes, W J; Heinzelmann, G; Henderson, R C W; Henschel, H; Herynek, I; Hess, M F; Hewitt, K; Hildesheim, W; Hiller, K H; Hilton, C D; Hladky, J; Hoeger, K C; Hoffmann, D; Holtom, T; Hoppner, M; Horisberger, R P; Hudgson, V L; Hufnagel, H; Hütte, M; Ibbotson, M; Itterbeck, H; Jacholkowska, A; Jacobsson, C; Jaffré, M; Janoth, J; Jansen, T; Johnson, D P; Jung, H; Jönsson, L B; Kalmus, Peter I P; Kander, M; Kant, D; Kaschowitz, R; Kathage, U; Katzy, J M; Kaufmann, H H; Kaufmann, O; Kazarian, S; Kenyon, Ian Richard; Kermiche, S; Keuker, C; Kiesling, C; Klein, M; Kleinwort, C; Knies, G; Kolanski, H; Kole, F; Kolya, S D; Korbel, V; Korn, M; Kostka, P; Kotelnikov, S K; Krasny, M W; Krehbiel, H; Krämerkämper, T; Krücker, D; Kuhlen, M; Kurca, T; Kurzhofer, J; Köhler, T; Köhne, J H; Küster, H; Lacour, D; Laforge, B; Lander, R; Landon, M P J; Lange, W; Langenegger, U; Laporte, J F; Lebedev, A; Lehner, F; Levonian, S; Lindström, G; Lindstrøm, M; Link, J; Linsel, F; Lipinski, J; List, B; Lobo, G; Loch, P; Lomas, J W; Lubimov, V; Lüke, D; López, G C; Magnussen, N; Malinovskii, E I; Mani, S; Maracek, R; Marage, P; Marks, J; Marshall, R; Martens, J; Martin, G; Martin, R D; Martyn, H U; Martyniak, J; Mavroidis, A; Maxfield, S J; McMahon, S J; Mehta, A; Meier, K; Meyer, A; Meyer, H; Meyer, J; Meyer, P O; Migliori, A; Mikocki, S; Milstead, D; Moeck, J; Moreau, F; Morris, J V; Mroczko, E; Murín, P; Müller, G; Müller, K; Nagovitsin, V; Nahnhauer, R; Naroska, Beate; Naumann, T; Negri, I; Newman, P R; Newton, D; Neyret, D; Nguyen, H K; Nicholls, T C; Niebergall, F; Niebuhr, C B; Niedzballa, C; Niggli, H; Nisius, R; Nowak, G; Noyes, G W; Nyberg-Werther, M; Oakden, M N; Oberlack, H; Olsson, J E; Ozerov, D; Palmen, P; Panaro, E; Panitch, A; Pascaud, C; Patel, G D; Pawletta, H; Peppel, E; Phillips, J P; Pieuchot, A; Pitzl, D; Pope, G; Prell, S; Pérez, E; Rabbertz, K; Reimer, P; Reinshagen, S; Rick, Hartmut; Riech, V; Riedlberger, J; Riepenhausen, F; Riess, S; Rizvi, E; Robertson, S M; Robmann, P; Roloff, H E; Roosen, R; Rosenbauer, K; Rostovtsev, A A; Rouse, F; Royon, C; Rusakov, S V; Rybicki, K; Rädel, G; Rüter, K; Sankey, D P C; Schacht, P; Schiek, S; Schleif, S; Schleper, P; Schmidt, D; Schmidt, G; Schröder, V; Schuhmann, E; Schwab, B; Schöning, A; Sefkow, F; Seidel, M; Sell, R; Semenov, A A; Shekelian, V I; Shevyakov, I; Shtarkov, L N; Siegmon, G; Siewert, U; Sirois, Y; Skillicorn, Ian O; Smirnov, P; Smith, J R; Solochenko, V; Soloviev, Yu V; Specka, A E; Spiekermann, J; Spielman, S; Spitzer, H; Squinabol, F; Starosta, R; Steenbock, M; Steffen, P; Steinberg, R; Steiner, H; Steinhart, J; Stella, B; Stellberger, A; Stier, J; Stiewe, J; Stolze, K; Straumann, U; Struczinski, W; Stösslein, U; Sutton, J P; Tapprogge, Stefan; Tasevsky, M; Theissen, J; Thiebaux, C; Thompson, G; Truöl, P; Tsipolitis, G; Turnau, J; Tutas, J; Uelkes, P; Usik, A; Valkár, S; Valkárová, A; Vallée, C; Van Esch, P; Van Mechelen, P; Van den Plas, D; Vazdik, Ya A; Verrecchia, P; Villet, G; Wacker, K; Wagener, A; Wagener, M; Walther, A; Waugh, B; Weber, G; Weber, M; Wegener, D; Wegner, A; Wengler, T; Werner, M; West, L R; Wiesand, S; Wilksen, T; Willard, S; Winde, M; Winter, G G; Wittek, C; Wobisch, M; Wünsch, E; Zarbock, D; Zhang, Z; Zhokin, A S; Zini, P; Zomer, F; Zsembery, J; Zuber, K; Zur Nedden, M; Zácek, J; de Roeck, A; von Schlippe, W

    1996-01-01

    Using the H1 detector at HERA, charged particle multiplicity distributions in deep inelastic ep scattering have been measured over a large kinematical region. The evolution with $W$ and $Q^2$ of the multiplicity distribution and of the multiplicity moments in pseudorapidity domains of varying size is studied in the current fragmentation region of the hadronic centre-of-mass frame. The results are compared with data from fixed target lepton-nucleon interactions, $e^+e^-$ annihilations and hadron-hadron collisions as well as with expectations from QCD based parton models. Fits to the Negative Binomial and Lognormal distributions are presented.

  4. 'DIAMANT': A 4 π light charged particle detector array

    International Nuclear Information System (INIS)

    4π γ-spectrometers allow precise determination of weak transitions. A 4π light charged particle detector array of 54 detectors called DIAMANT is described as applied for triggering γ-spectrometers. The multidetector system allows channel selection, increases the sensitivity of the spectrometer, and can give additional information on the exit channel and the path leading to the final nucleus studied by its γ emission. The characteristics and first measured performance of the DIAMANT multidetector array are presented. (R.P.) 2 refs

  5. Energy loss of charged particles colliding with an oscillator

    Science.gov (United States)

    Makarov, D. N.

    2015-04-01

    Energy loss of fast charged particles colliding with an oscillator is considered in the dipole approximation. In this approximation, the problem is solved exactly and the energy loss of the oscillator from the initial state | m> = |0> is found in the form of the sum of single integrals. It is shown that passing to the limit, the Bethe theory for an atom with small perturbations can be obtained, and in the case of strong fields, the correction to the Bethe theory, analogous to the Bloch correction, can be calculated; in addition, a classical limit coinciding with the Bohr formula is possible.

  6. On the energy losses of fast charged particles

    Science.gov (United States)

    Matveev, V. I.; Makarov, D. N.; Gusarevich, E. S.

    2010-09-01

    The energy losses of fast charged particles colliding with atoms have been considered in the eikonal approximation. It has been shown that the nonperturbative contribution to the effective stopping from the region of the intermediate impact parameters (comparable with the characteristic sizes of the electron shells of the target) not only can be significant as compared to shell corrections to the Bethe-Bloch formula (usually considered in the first order of perturbation theory), but also can provide significant (up to 50%) corrections to this formula.

  7. Failure of the capsule for coated particles irradiation

    International Nuclear Information System (INIS)

    During operation cycle No. 27 of the JMTR (Japan Material Testing Reactor) on May 20, 1974, leakage of the fission product gas occurred from the capsule 72F-7A, which contained coated particles for the irradiation; the coated particles are for the development of a multi-purpose high temperature gas cooled reactor. The capsule was designed for heat 16000C. Three nickel plates as the heat reflector were sandwiched in between the plates of titanium and zirconium, which were adsorbents for the impurity gases in the cladding tube (Nb-1%Zr). Temperatures of the plates were about 10000C under the irradiation, so one metal diffused into the other metal through interfaces, resulting in the formation of an alloy. Its melting point was lower than those of metals in the capsule. The cladding material Nb-1%Zr was melted by the alloy and finally a pin hole developed through the cladding. The process of failure, design of the capsule, post-irradiation test of the capsule and the failure-reproducing experiment with a mock-up capsule are described. (auth.)

  8. Development of Si (Li) detectors for charged particles spectrometer

    CERN Document Server

    Onabe, H; Obinata, M; Kashiwagi, T

    2002-01-01

    Lithium drifted silicon (Si (Li)) detectors with high-quality large area for charged particles spectrometer abroad artificial satellite have been developed. Surface stability can be obtained by thin p-n junction fabricated with the applied photo engraving process (PEP) instead of surface barrier. The region compensated with Lithium can be improved by the adequate heat treatment, and this improvement can be monitored by means of a combination of copper plating and subsequent micro-XRF analysis. The detectors fabricated from the thermal treated wafers were found to have better energy resolution both for alpha-particles from sup 2 sup 4 sup 1 Am and conversion electrons from sup 2 sup 0 sup 7 Bi. (author)

  9. Physical sputtering of metallic systems by charged-particle impact

    International Nuclear Information System (INIS)

    The present paper provides a brief overview of our current understanding of physical sputtering by charged-particle impact, with the emphasis on sputtering of metals and alloys under bombardment with particles that produce knock-on collisions. Fundamental aspects of ion-solid interactions, and recent developments in the study of sputtering of elemental targets and preferential sputtering in multicomponent materials are reviewed. We concentrate only on a few specific topics of sputter emission, including the various properties of the sputtered flux and depth of origin, and on connections between sputtering and other radiation-induced and -enhanced phenomena that modify the near-surface composition of the target. The synergistic effects of these diverse processes in changing the composition of the integrated sputtered-atom flux is described in simple physical terms, using selected examples of recent important progress. 325 refs., 27 figs

  10. Search for fractional charge and heavy stable particles at PETRA

    International Nuclear Information System (INIS)

    A search has been made for new particles with charge Q = 2/3, 1, 4/3, 5/3 produced in e+e--reactions at PETRA. The energy range was Esub(cm) = 27-35 GeV. No such particles were found. Upper limits for the cross-section depending on the assumed mass and production spectrum are given. For Q = 2/3 quarks with mass less than 12 GeV/c2, upper limits sigma(q anti q)/sigma(μμ) -2 (90% C.L.) are obtained both for inclusive and exclusive production. For the lifetime of the B-meson (msub(B) = 5 GeV/c2) an upper limit tau -9 s is obtained. (orig.)

  11. EGUN, Charged Particle Trajectories in Electromagnetic Focusing System

    International Nuclear Information System (INIS)

    1 - Description of problem or function: EGUN computes trajectories of charged particles in electrostatic and magnetostatic focusing systems including the effects of space charge and self-magnetic fields. Starting options include Child's Law conditions on cathodes of various shapes, user-specified conditions input for each ray, and a combination of Child's Law conditions and user specifications. Either rectangular or cylindrically symmetric geometry may be used. Magnetic fields may be specified using an arbitrary configuration of coils, or the output of a magnet program, such as Poisson, or by an externally calculated array of the axial fields. 2 - Method of solution: The program first solves Laplace's equation. Next, the first iteration of electron trajectories is started using one of the four starting options. On the first iteration cycle, space charge forces are calculated from the assumption of paraxial flow. As the rays are traced, space charge is computed and stored. After all the electron trajectories have been calculated, the program begins the second cycle by solving the Poisson equation with the space charge from the first iteration. Subsequent iteration cycles follow this pattern. The Poisson equation is solved by an alternate column relaxation technique known as the semi-iterative Chebyshev method. A fourth-order Runge-Kutta method is used to solve the relativistic differential equations of the trajectory calculations. 3 - Restrictions on the complexity of the problem - Maxima of: 9001 mesh points in a square mesh, 300 mesh points in the axial direction, 100 mesh points in the radial direction, 101 potentials, 51 rays. In the cylindrical coordinates, the magnetic fields are axially symmetric. In rectangular coordinates, the external field is assumed to be normal to the plane of the problem, which is assumed to be the median plane

  12. Charging and coagulation of radioactive and nonradioactive particles in the atmosphere

    Directory of Open Access Journals (Sweden)

    Y.-H. Kim

    2015-09-01

    Full Text Available Charging and coagulation influence one another and impact the particle charge and size distributions in the atmosphere. However, few investigations to date have focused on the coagulation kinetics of atmospheric particles accumulating charge. This study presents three approaches to include mutual effects of charging and coagulation on the microphysical evolution of atmospheric particles such as radioactive particles. The first approach employs ion balance, charge balance, and a bivariate population balance model (PBM to comprehensively calculate both charge accumulation and coagulation rates of particles. The second approach involves a much simpler description of charging, and uses a monovariate PBM and subsequent effects of charge on particle coagulation. The third approach is further simplified assuming that particles instantaneously reach their steady-state charge distributions. It is found that compared to the other two approaches, the first approach can accurately predict time-dependent changes in the size and charge distributions of particles over a wide size range covering from the free molecule to continuum regimes. The other two approaches can reliably predict both charge accumulation and coagulation rates for particles larger than about 40 nm and atmospherically relevant conditions. These approaches are applied to investigate coagulation kinetics of particles accumulating charge in a radioactive neutralizer, the urban atmosphere, and a radioactive plume. Limitations of the approaches are discussed.

  13. Radiation hardness and charge collection efficiency of lithium irradiated thin silicon diodes

    CERN Document Server

    Boscardin, Maurizio; Bruzzi, Mara; Candelori, Andrea; Focardi, Ettore; Khomenkov, Volodymyr P; Piemonte, Claudio; Ronchin, S; Tosi, C; Zorzi, N

    2005-01-01

    Due to their low depletion voltage, even after high particle fluences, improved tracking precision and momentum resolution, and reduced material budget, thin substrates are one of the possible choices to provide radiation hard detectors for future high energy physics experiments. In the framework of the CERN RD50 Collaboration, we have developed PIN diode detectors on membranes obtained by locally thinning the silicon substrate by means of TMAH etching from the wafer backside. Diodes of different shapes and sizes have been fabricated on 50- mu m and 100- mu m thick membranes and tested, showing a low leakage current (of 300 nA/cm/sup 3/) and a very low depletion voltage (in the order of 1 V for the 50 mu m membrane) before irradiation. Radiation damage tests have been performed with 58 MeV lithium (Li) ions up to the fluence of 10/sup 14/ Li/cm/sup 2/ in order to determine the depletion voltage and leakage current density increase after irradiation. Charge collection efficiency tests carried out with a beta /...

  14. Amorphization of complex ceramics by heavy-particle irradiations

    International Nuclear Information System (INIS)

    Complex ceramics, for the purpose of this paper, include materials that are generally strongly bonded (mixed ionic and covalent), refractory and frequently good insulators. They are distinguished from simple, compact ceramics (e.g., MgO and UO2) by structural features which include: (1) open network structures, best characterized by a consideration of the shape, size and connectivity of coordination polyhedra; (2) complex compositions which characteristically lead to multiple cation sites and lower symmetry; (3) directional bonding; (4) bond-type variations within the structure. The heavy particle irradiations include ion-beam irradiations and recoil-nucleus damage resulting from a-decay events from constituent actinides. The latter effects are responsible for the radiation-induced transformation to the metamict state in minerals. The responses of these materials to irradiation are complex, as energy may be dissipated ballistically by transfer of kinetic energy from an incident projectile or radiolytically by conversion of radiation-induced electronic excitations into atomic motion. This results in isolated Frenkel defect pairs, defect aggregates, isolated collision cascades or bulk amorphization. Thus, the amorphization process is heterogeneous. Only recently have there been systematic studies of heavy particle irradiations of complex ceramics on a wide variety of structure-types and compositions as a function of dose and temperature. In this paper, we review the conditions for amorphization for the tetragonal orthosilicate, zircon [ZrSiO4]; the hexagonal orthosilicate/phosphate apatite structure-type [X10(ZO4)6(F,Cl,O)2]; the isometric pyrochlores [A1-2B2O6(O,OH,F)0-1pH2O] and its monoclinic derivative zirconotite [CaZrTi2O7]; the olivine (derivative - hcp) structure types, α-VIA2IVBO4, and spinel (ccp), γ-VIA2IVBO4

  15. Anomalous Kinetics of Hard Charged Particles Dynamical Renormalization Group Resummation

    CERN Document Server

    Boyanovsky, D

    1999-01-01

    We study the kinetics of the distribution function for charged particles of hard momentum in scalar QED. The goal is to understand the effects of infrared divergences associated with the exchange of quasistatic magnetic photons in the relaxation of the distribution function. We begin by obtaining a kinetic transport equation for the distribution function for hard charged scalars in a perturbative expansion that includes hard thermal loop resummation. Solving this transport equation, the infrared divergences arising from absorption and emission of soft quasi-static magnetic photons are manifest in logarithmic secular terms. We then implement the dynamical renormalization group resummation of these secular terms in the relaxation time approximation. The distribution function (in the linearized regime) is found to approach equilibrium as $\\delta n_k(t) =\\delta n_k(t_o) e^{-2\\alpha T (t-t_o) and $\\alpha =e^2/4\\pi$. This anomalous relaxation is recognized to be the square of the relaxation of the single particle p...

  16. Particle beams carrying orbital angular momentum, charge, mass and spin

    Science.gov (United States)

    Tijssen, Teuntje; Hayrapetyan, Armen; Goette, Joerg; Dennis, Mark

    Electron beams carrying vortices and angular momentum have been of much experimental and theoretical interest in recent years. In addition, optical vortex beams are a well-established field in optics and photonics. In both cases, the orbital angular momentum associated with the beam's axial vortex has effects on the overall spin of the beam, due to spin-orbit interactions. A simple model of these systems are Bessel beam solutions (of either the Dirac equation or Maxwell equations) with a nonzero azimuthal quantum number, which are found by separation in cylindrical coordinates. Here, we generalize this approach, considering the classical field theory of Bessel beams for particles which are either massive or massless, uncharged or charged and of a variety of different spins (0, 1/2, 1, ⋯). We regard the spin and helicity states and different forms of spin-orbit terms that arise. Moreover, we analyse the induced electromagnetic field when the particles carry charge. Most importantly, this unified field theory approach leads to the prediction of effects for vortex beams of neutrons, mesons and neutrinos.

  17. Modeling of mesoscopic electrokinetic phenomena using charged dissipative particle dynamics

    Science.gov (United States)

    Deng, Mingge; Li, Zhen; Karniadakis, George

    2015-11-01

    In this work, we propose a charged dissipative particle dynamics (cDPD) model for investigation of mesoscopic electrokinetic phenomena. In particular, this particle-based method was designed to simulate micro- or nano- flows which governing by Poisson-Nernst-Planck (PNP) equation coupled with Navier-Stokes (NS) equation. For cDPD simulations of wall-bounded fluid systems, a methodology for imposing correct Dirichlet and Neumann boundary conditions for both PNP and NS equations is developed. To validate the present cDPD model and the corresponding boundary method, we perform cDPD simulations of electrostatic double layer (EDL) in the vicinity of a charged wall, and the results show good agreement with the mean-field theoretical solutions. The capacity density of a parallel plate capacitor in salt solution is also investigated with different salt concentration. Moreover, we utilize the proposed methodology to study the electroosmotic and electroosmotic/pressure-driven flow in a micro-channel. In the last, we simulate the dilute polyelectrolyte solution both in bulk and micro-channel, which show the flexibility and capability of this method in studying complex fluids. This work was sponsored by the Collaboratory on Mathematics for Mesoscopic Modeling of Materials (CM4) supported by DOE.

  18. Charging and defect formation in the KCl-Si(111) thin layers under slow electron irradiation

    International Nuclear Information System (INIS)

    The processes of defect formation and charge accumulation in thin KCl-Si(111) films irradiated with electron beam of energies 4-300 e V was studied by total current spectroscopy methods. It was shown that by irradiated electron beam energies Ep ≥ 8 eV in low energies regions of spectrum the peak characteristic for F-, M- and R-centers appeared. Defects formation threshold in KCl was equal to forbidden band energies. The growth of concentration F-, M- and R-centers with increasing irradiated dose and energies was observed. Electron bombardment is accompanied by accumulation of surface charges are connected with captured electrons and hole traps

  19. Charged particle therapy for cancer: The inheritance of the Cavendish scientists?

    Energy Technology Data Exchange (ETDEWEB)

    Jones, Bleddyn [Department of Clinical Oncology, Queen Elizabeth University Hospital, University Hospitals NHS Trust, Birmingham University, Edgbaston, Birmingham B15 2TH (United Kingdom)], E-mail: b.jones.1@bham.ac.uk; Dale, Roger G.; Carabe-Fernandez, Alejandro [Department of Radiation Physics and Radiobiology, Imperial College Healthcare NHS Trust, Charing Cross Hospital, London W6 8RF (United Kingdom)

    2009-03-15

    The history of developments in atomic physics and its applications follows the decisive input provided by Maxwell and subsequent discoveries by his successors at the Cavendish Laboratory. In medicine the potential applications of particle physics (with the notable exception of the electron) were unfortunately delayed by the disappointing experiences with neutron therapy, which produced long-term scepticism. Neutrons are not appropriate for cancer therapy because not only their physical dose distributions offer no advantages over X-rays, but also their biological dose distributions are worse. The much improved dose distributions achieved with charged particles offer real prospects for better treatment outcomes because of the large reduction in the volume of unnecessarily irradiated tissue in many situations. Charged particle therapy is relatively new and can be applied with increasing confidence due to advances in radiology and computing, but at present there are insufficient numbers of treatment facilities to produce statistically powerful studies to compare treatment outcomes with those of X-rays. Considerable progress has been achieved in Japan and Germany with pilot studies of carbon ions but their efficacy compared with protons needs to be tested: in theory carbon should be better for intrinsically radio-resistant and for the most hypoxic tumours. The optimisation of proton and ion beam therapy in clinical practice remains to be achieved, but there are good scientific reasons why these modalities will be preferred by patients and their physicians in the future. Regrettably, despite hosting many of the momentous discoveries that enabled the development of charged particle therapy, the UK is slow to adopt and implement this very important form of cancer treatment.

  20. Aspects of space charge theory applied to dielectric under electron beam irradiation

    International Nuclear Information System (INIS)

    Irradiation of solid dielectric with electron beams has been used as a power full tool in investigations of charge storage and transport in such materials. Some of the results that have been obtained in this area are reviewed and the formulation of a transport equation for excess charge in irradiated insulators is dicussed. This equation is subsequently applied to various experimental set-ups. It is found that space charge effects play an essential role in the establishment of stationary currents in samples subject to quasi-penetrating electron beams. Such effects may, however, be neglected for low electron ranges. Theoretical results are in good agreement with experimental findings by Spear (1955)

  1. Response of Charged Particles in a Storage Ring to Gravitational Waves

    Institute of Scientific and Technical Information of China (English)

    DONGDong; HUANGChao-Guang

    2003-01-01

    The influence of gravitational waves on the charged particles in a storage ring is studied. It shows that the gravitational waves might be directly detected by monitoring the motion of charged particles in a storage ring. The angular velocity of the charged particles is continually adjustable by changing the initial energy of particles and the strength of the magnetic field. This feature is very useful for finding the gravitational waves with different frequencies.

  2. Response of Charged Particles in a Storage Ring to Gravitational Waves

    Institute of Scientific and Technical Information of China (English)

    DONG Dong; HUANG Chao-Guang

    2003-01-01

    The influence of gravitational waves on the charged particles in a storage ring is studied. It shows thatthe gravitational waves might be directly detected by monitoring the motion of charged particles in a storage ring. Theangular velocity of the charged particles is continually adjustable by changing the initial energy of particles and thestrength of the magnetic field. This feature is very useful for finding the gravitational waves with different frequencies.

  3. Charged and Neutral Particles Channeling Phenomena Channeling 2008

    Science.gov (United States)

    Dabagov, Sultan B.; Palumbo, Luigi

    2010-04-01

    On the discovery of coherent Bremsstrahlung in a single crystal at the Frascati National Laboratories / C. Barbiellini, G. P. Murtas and S. B. Dabagov -- Advances in coherent Bremsstrahlung and LPM-effect studies (to the lOOth anniversary from the birth of L. D. Landau) / N. F. Shul'ga -- Spectra of radiation and created particles at intermediate energy in oriented crystal taking into account energy loss / V. N. Baier and V. M. Katkov -- The coherent Bremsstrahlung beam at MAX-lab facility / K. Fissum ... [et al.] -- Radiation from thin, structured targets (CERN NA63) / A. Dizdar -- Hard incoherent radiation in thick crystals / N. F. Shul'ga, V. V. Syshchenko and A. I. Tarnovsky -- Coherent Bremsstrahlung in periodically deformed crystals with a complex base / A. R. Mkrtchyan, A. A. Saharian and V. V. Parazian -- Induction of coherent x-ray Bremsstrahlung in crystals under the influence of acoustic waves / A. R. Mkrtchyan and V. V. Parazian -- Coherent processes in bent single crystals / V. A. Maisheev -- Experimental and theoretical investigation of complete transfer phenomenon for media with various heat exchange coefficients / A. R. Mkrtchyan, A. E. Movsisyan and V. R. Kocharyan -- Coherent pair production in crystals / A. R. Mkrtchyan, A. A. Saharian and V. V. Parazian -- Negative particle planar and axial channeling and channeling collimation / R. A. Carrigan, Jr. -- CERN crystal-based collimation in modern hadron colliders / W. Scandale -- Studies and application of bent crystals for beam steering at 70 GeV IHEP accelerator / A. G. Afonin ... [et al.] -- Crystal collimation studies at the Tevatron (T-980) / N. V. Mokhov ... [et al.] -- Fabrication of crystals for channeling of particles in accellerators / A. Mazzolari ... [et al.] -- New possibilities to facilitate collimation of both positively and negatively charged particle beams by crystals / V. Guidi, A. Mazzolari and V. V. Tikhomirov -- Increase of probability of particle capture into the channeling

  4. Fractional dynamics of charged particles in magnetic fields

    Science.gov (United States)

    Coronel-Escamilla, A.; Gómez-Aguilar, J. F.; Alvarado-Méndez, E.; Guerrero-Ramírez, G. V.; Escobar-Jiménez, R. F.

    2016-02-01

    In many physical applications the electrons play a relevant role. For example, when a beam of electrons accelerated to relativistic velocities is used as an active medium to generate Free Electron Lasers (FEL), the electrons are bound to atoms, but move freely in a magnetic field. The relaxation time, longitudinal effects and transverse variations of the optical field are parameters that play an important role in the efficiency of this laser. The electron dynamics in a magnetic field is a means of radiation source for coupling to the electric field. The transverse motion of the electrons leads to either gain or loss energy from or to the field, depending on the position of the particle regarding the phase of the external radiation field. Due to the importance to know with great certainty the displacement of charged particles in a magnetic field, in this work we study the fractional dynamics of charged particles in magnetic fields. Newton’s second law is considered and the order of the fractional differential equation is (0;1]. Based on the Grünwald-Letnikov (GL) definition, the discretization of fractional differential equations is reported to get numerical simulations. Comparison between the numerical solutions obtained on Euler’s numerical method for the classical case and the GL definition in the fractional approach proves the good performance of the numerical scheme applied. Three application examples are shown: constant magnetic field, ramp magnetic field and harmonic magnetic field. In the first example the results obtained show bistability. Dissipative effects are observed in the system and the standard dynamic is recovered when the order of the fractional derivative is 1.

  5. Integral charged particle nuclear date bibliography. Editon 1, Supplement 2

    International Nuclear Information System (INIS)

    This bibliography is divided into three sections, ''References'', ''Target Index'', and ''Residual Index.'' The ''References'' section contains all references satisfying the following criteria: excitation functions, thick targets, or product yield leading to the formation of a ground or metastable state; the atomic mass and charge of the incident particle must be greater than or equal to 1; the atomic mass of the target must be greater than or equal to 1; and the atomic masses of the outgoing and residual nuclei must be greater than or equal to 1 with the exception of processes which do not lead to a definite residual nucleus and of gamma-ray production cross sections. The ''Target Index'' section contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite target nucleus and reaction. These reference lines contain the Journal name, followed by the volume and page number. The ''Residual Index'' section also contains the incident particle energy and the abbreviated reference lines for all the entries, which contain information on a definite residual nucleus and a definite target-reaction

  6. Chaotic phenomena of charged particles in crystal lattices.

    Science.gov (United States)

    Desalvo, Agostino; Giannerini, Simone; Rosa, Rodolfo

    2006-06-01

    In this article, we have applied the methods of chaos theory to channeling phenomena of positive charged particles in crystal lattices. In particular, we studied the transition between two ordered types of motion; i.e., motion parallel to a crystal axis (axial channeling) and to a crystal plane (planar channeling), respectively. The transition between these two regimes turns out to occur through an angular range in which the particle motion is highly disordered and the region of phase space spanned by the particle is much larger than the one swept in the two ordered motions. We have evaluated the maximum Lyapunov exponent with the method put forward by Rosenstein et al. [Physica D 65, 117 (1993)] and by Kantz [Phys. Lett. A 185, 77 (1994)]. Moreover, we estimated the correlation dimension by using the Grassberger-Procaccia method. We found that at the transition the system exhibits a very complex behavior showing an exponential divergence of the trajectories corresponding to a positive Lyapunov exponent and a noninteger value of the correlation dimension. These results turn out to be linked to a physical interpretation. The Lyapunov exponents are in agreement with the model by Akhiezer et al. [Phys. Rep. 203, 289 (1991)], based on the equivalence between the ion motion along the crystal plane described as a "string of strings" and the "kicked" rotator. The nonintegral value of the correlation dimension can be explained by the nonconservation of transverse energy at the transition. PMID:16822017

  7. Plasmas for Thermonuclear Research Produced by Laser Beam Irradiation of Single Solid Particles

    International Nuclear Information System (INIS)

    A ruby laser was used to form a high-temperature, high-density plasma from a single, solid particle of lithium hydride suspended in a vacuum. The 10 to 50 micron diameter particle was charged by an electron beam and suspended in a vacuum in the electric field produced by a cubical array of electrodes of which opposite pairs were connected to the terminals of a Y-connected, three-phase alternating current supply. The focused 20-nsec, 30-MW giant-pulse beam from a Q-spoiled ruby laser irradiated the suspended particle and produced an extremely high-density, high-temperature plasma. Charge collection measurements showed that complete single ionization of the 1015 atoms in the lithium hydride was achieved in the plasmas produced. Time-of-flight studies of the expanding plasma yield initial plasma temperatures of 10 to 100 eV. Since the ionization was produced in a vacuum, there was no collisional cooling of this high-energy plasma. The plasmas had a uniform radial expansion, high densities and temperatures, and zero net currents within the plasma - a set of properties which make them particularly interesting for plasma confinement studies and controlled thermonuclear investigations. Further studies of these laser-irradiated, single particle plasmas are in progress and include flux coil measurements of the expanding plasma in a magnetic field, spectroscopic determination of ion excited temperatures, examination of the scattering and absorption of the incident laser beam by the plasma, and measurements of the containment lifetime of these unusual plasmas in magnetic confinement fields. (author)

  8. Charge collection efficiency of GaAs detectors studied with low-energy heavy charged particles

    CERN Document Server

    Bates, R; Linhart, V; O'Shea, V; Pospísil, S; Raine, C; Smith, K; Sinor, M; Wilhelm, I

    1999-01-01

    Epitaxially grown GaAs layers have recently been produced with sufficient thickness and low enough free carrier concentration to permit their use as radiation detectors. Initial tests have shown that the epi-material behaves as a classical semiconductor as the depletion behaviour follows the square root dependency on the applied bias. This article presents the results of measurements of the growth of the active depletion depth with increasing bias using low-energy protons and alpha particles as probes for various depths and their comparison to values extrapolated from capacitance measurements. From the proton and alpha particle spectroscopic measurements, an active depth of detector material that collects 100% of the charge generated inside it was determined. The consistency of these results with independent capacitance measurements supports the idea that the GaAs epi-material behaves as a classical semiconductor. (author)

  9. Charged particle and laser irradiation of selected materials

    International Nuclear Information System (INIS)

    The main topics of the present thesis are the processes governing electronic sputtering of insulators and laser ablation of metals and insulators. The sputtering yield for electron bombardment of solid deuterium was investigated using quartz crystal microbalances as the measuring technique. The sputtering yield was measured with varying electron energy and deuterium film thickness. Laser ablation measurements of silver and nickel were carried out using a Nd:YAG laser. The effect of various experimental parameters such as background gas pressure (Ar, N2), position of quartz crystals with respect to target position and the optimal number of laser shots for carrying out the experiments were investigated. The deposition rate was measured with varying laser wavelength and laser fluence. The angular distribution of the ablated material was measured for silver as well. A theoretical model based on the thermal properties of laser interaction with metals was applied in the initial phase of ablation. For the non-thermal processes governing laser interaction with the ablated plasma plume, a model developed by Phipps and Dreyfus was used to interpret the results. Laser ablation measurements of water-ice were carried using a Nitrogen laser. Attempts were made to measure the deposition rate for various the laser wavelengths and energies. (au) 8 tabs., 49 ills., 77 refs

  10. Coherent polarization radiation from crystals irradiated with relativistic charged particles

    International Nuclear Information System (INIS)

    When polarization radiation (polarization bremsstrahlung) occurs in a crystal, the radiation becomes coherent in X-ray wavelengths. This radiation, called coherent polarization radiation (CPR) in this paper, is considered as a possible compact X-ray source because CPR is intense, monochromatic, tunable, small background, and easy to extract. We present a simple theory of CPR with emphasis on its relation to Cherenkov radiation and transition radiation. Various properties of CPR are also discussed

  11. Charged particle and laser irradiation of selected materials

    Energy Technology Data Exchange (ETDEWEB)

    Svendsen, W.E.

    1996-11-01

    The main topics of the present thesis are the processes governing electronic sputtering of insulators and laser ablation of metals and insulators. The sputtering yield for electron bombardment of solid deuterium was investigated using quartz crystal microbalances as the measuring technique. The sputtering yield was measured with varying electron energy and deuterium film thickness. Laser ablation measurements of silver and nickel were carried out using a Nd:YAG laser. The effect of various experimental parameters such as background gas pressure (Ar, N{sub 2}), position of quartz crystals with respect to target position and the optimal number of laser shots for carrying out the experiments were investigated. The deposition rate was measured with varying laser wavelength and laser fluence. The angular distribution of the ablated material was measured for silver as well. A theoretical model based on the thermal properties of laser interaction with metals was applied in the initial phase of ablation. For the non-thermal processes governing laser interaction with the ablated plasma plume, a model developed by Phipps and Dreyfus was used to interpret the results. Laser ablation measurements of water-ice were carried using a Nitrogen laser. Attempts were made to measure the deposition rate for various the laser wavelengths and energies. (au) 8 tabs., 49 ills., 77 refs.

  12. Charge collection and charge sharing in heavily irradiated n-side read-out silicon microstrip detectors

    International Nuclear Information System (INIS)

    Hadron radiation damage of n-bulk silicon detectors leads to a change in the effective space charge from positive to negative. This effect is called type inversion. Type inversion occurs after exposure to a fluence of a few 1013 proton cm-2 and is characterized by migration of the diode junction to the n+ implanted side (n-side) of the detector. After inversion the charge collection efficiency (CCE) of segmented detectors at low voltage is higher when the n-side, rather than the p-side, is read out. A p-side read out (p-in-n) and an n-side read out (n-in-n) strip detector with identical strip geometry and a wafer thickness of 200 μm were simultaneously and inhomogenously irradiated to a maximum fluence of 7x1014 proton cm-2 with 24 GeV c-1 protons. A comparison of the CCE at very high irradiation doses is shown with these two read out geometries. The inhomogeneous irradiation induces an inhomogenous distribution of the effective space charge with a transverse component of the electric field that could in principle affect the resolution properties of the microstrip detector. The inter-strip charge sharing properties, as a function of dose, for the n-in-n detector have been measured. No systematic distortion of the reconstructed cluster position was detected within the limits of the measurement accuracy. The detectors were manufactured using oxygen enriched silicon substrates to limit the degradation of the full depletion voltage under charged hadron irradiation. The measured CCE confirms that the use of oxygenated n-in-n detectors is viable up to fluences of 7x1014 proton cm-2

  13. Weakly nonlinear electrophoresis of a highly charged colloidal particle

    Science.gov (United States)

    Schnitzer, Ory; Zeyde, Roman; Yavneh, Irad; Yariv, Ehud

    2013-05-01

    At large zeta potentials, surface conduction becomes appreciable in thin-double-layer electrokinetic transport. In the linear weak-field regime, where this effect is quantified by the Dukhin number, it is manifested in non-Smoluchowski electrophoretic mobilities. In this paper we go beyond linear response, employing the recently derived macroscale model of Schnitzer and Yariv ["Macroscale description of electrokinetic flows at large zeta potentials: Nonlinear surface conduction," Phys. Rev. E 86, 021503 (2012), 10.1103/PhysRevE.86.021503] as the infrastructure for a weakly nonlinear analysis of spherical-particle electrophoresis. A straightforward perturbation in the field strength is frustrated by the failure to satisfy the far-field conditions, representing a non-uniformity of the weak-field approximation at large distances away from the particle, where salt advection becomes comparable to diffusion. This is remedied using inner-outer asymptotic expansions in the spirit of Acrivos and Taylor ["Heat and mass transfer from single spheres in Stokes flow," Phys. Fluids 5, 387 (1962), 10.1063/1.1706630], with the inner region representing the particle neighborhood and the outer region corresponding to distances scaling inversely with the field magnitude. This singular scheme furnishes an asymptotic correction to the electrophoretic velocity, proportional to the applied field cubed, which embodies a host of nonlinear mechanisms unfamiliar from linear electrokinetic theories. These include the effect of induced zeta-potential inhomogeneity, animated by concentration polarization, on electro-osmosis and diffuso-osmosis; bulk advection of salt; nonuniform bulk conductivity; Coulomb body forces acting on bulk volumetric charge; and the nonzero electrostatic force exerted upon the otherwise screened particle-layer system. A numerical solution of the macroscale model validates our weakly nonlinear analysis.

  14. Search for multiply charged Heavy Stable Charged Particles in data collected with the CMS detector

    Energy Technology Data Exchange (ETDEWEB)

    Veeraraghavan, Venkatesh [Florida State Univ., Tallahassee, FL (United States)

    2013-10-30

    Several models of new physics yield particles that are massive, long-lived, and have an electric charge, Q, greater than that of the electron, e. A search for evidence of such particles was performed using 5.0 fb-1 and 18.8 fb-1 of proton-proton collision data collected at √s = 7 TeV and √s = 8 TeV, respectively, with the Compact Muon Solenoid detector at the Large Hadron Collider. The distinctive detector signatures of these particles are that they are slow-moving and highly ionizing. Ionization energy loss and time-of- flight measurements were made using the inner tracker and the muon system, respectively. The search is sensitive to 1e ≤ |Q| ≤ 8e. Data were found to be consistent with standard model expectations and upper limits on the production cross section of these particles were computed using a Drell-Yan-like production model. Masses below 517, 687, 752, 791, 798, 778, 753, and 724 GeV are excluded for |Q| = 1e, 2e, 3e, 4e, 5e, 6e, 7e, and 8e, respectively.

  15. Particle with non-Abelian charge: classical and quantum

    CERN Document Server

    Lahiri, Amitabha

    2010-01-01

    We construct an action in the worldline formalism for a non-Abelian charged particle in a non-Abelian background field, described by real bosonic variables, leading to a set of the well known classical equations given by Wong. The isospin parts in the action can be viewed as the Lagrange multiplier term corresponding to a non-holonomic constraint restricting the isospins to be parallel transported. The path integration is performed over the isospin variables and their paths turn out to be constrained by its classical solution for the isospins. We derive a wave equation from the path integral, constructed as the constrained Hamiltonian operator acts on the wave function. It reveals what operator ordering corresponds to our classical Hamiltonian. It is verified by the inverse Weyl transformation.

  16. Japan Charged-Particle Nuclear Reaction Data Group (JCPRG)

    International Nuclear Information System (INIS)

    This it the progress report of the Executive Committee of the Japan Charged-Particle Nuclear Reaction Data Group (JCPRG). Since the last NRDC meeting in June 2003, the group has carried out the following activities: Compilation of CPND for NRDF and EXFOR; Compilation of CPND bibliographies for CINDA; Improvement of Web-based data input system HENDEL; Improvement of NRDF retrieval system DARPE; Development of utilization system for EXFOR and evaluated libraries; Data services for Japanese users. The regular JCPRG budget has ended at March 2001. They are applying a competitive budget for our further activity. The Executive Committee is organized by 7 researchers and 1 secretary. 6 postdoctoral researchers in Meme Media Lab. of Hokkaido Univ., 6 graduated students in Nuclear Physics Laboratory of Hokkaido Univ. and 1 technical staff work part-time. 1.5 equivalent man year is dedicated to NRDC Network activities

  17. A hybrid detector telescope for fission fragments and charged particles

    International Nuclear Information System (INIS)

    Measurement of light charged particle (LCP) multiplicities in coincidence with fission fragments (FFs) during the fusion-fission process is a very useful probe to understand the fission dynamics. In this type of measurement, the LCP's are indented to be measured in a wide range of relative angles (θrel) from 0° to 180° with respect to the FF direction. The conventional method of using two separate detectors one for the FF's and another for the LCPs does not allow to direct the LCPs along the direction of FF (in particular, θrel gas and Egas) and two CsI(Tl)-Si(PIN) detectors mounted at the end of the gas-section. In this paper, the results of in-beam usage of the HDT are presented

  18. General magnetized Weyl solutions: Disks and motion of charged particles

    CERN Document Server

    García-Duque, Cristian H

    2010-01-01

    We construct three families of general magnetostatic axisymmetric exact solutions of Einstein-Maxwell equations in spherical coordinates, prolate, and oblates. The solutions obtained are then presented in the system of generalized spheroidal coordinates which is a generalization of the previous systems. The method used to build such solutions is the well-known complex potential formalism proposed by Ernst, using as seed solutions vacuum solutions of the Einstein field equations. The constructed solutions are asymptotically flat and regular on the axis of symmetry. We show explicitly some particular solutions among them a Erez-Rosen type solution and a Morgan-Morgan type solution, which we interpret as the exterior gravitational field of a finite dislike source immersed in a magnetic field. From them we also construct using the well known ``displace, cut and reflect'' method exact solutions representing relativistic thin disks of infinite extension. We analyze the motion of electrically charged test particles ...

  19. Testing of high-vacuum pumps for charged particle accelerators

    International Nuclear Information System (INIS)

    To study a possibility of employing different types of pumps in charged-particle accelerators the following pumps have been tested: electric-arc, turbomolecular and cryogenic. The research has been carried out on a test bench which made it possible to determine the pumping-out rate for different gases (constant-volume methods), measure their limiting pressure and study the spectra of different gases by using mass spectrometers. It was possible also to warm up the pumps and pumped-out volumes. From these tests it was concluded that: (1) the electric-arc pump does not meet the accelerator pumping-out requirements; (2) the turbomolecular pump with a nitrogen-sorption trap can be recommended for pumping-out accelerators but requires modification of the supply unit; (3) the cryogenic pump can be recommended for pumpimg-out of accelerators but requires modification of the automatic system for replenishment of the cryogenic fluid

  20. A large solid angle detector for medium energy charged particles

    International Nuclear Information System (INIS)

    A charged particle detector with 0.7 sr solid angular acceptance has been built, principally to detect protons in the energy range 25-150 MeV in experiments with tagged photon beams. The detector consists of a three element ΔE1-ΔE2-E plastic scintillator telescope. Position information is obtained from the time difference between signals from the two ends of each scintillator. The design of the detector and tests of its performance are described. An energy resolution of 2.8 MeV fwhm at 60 MeV proton energy, and a two-dimensional position resolution of 24 mm x 41 mm fwhm has been obtained. Successful operation in the tagged photon environment is demonstrated. (orig.)

  1. Secondary charged particle activation method for measuring the tritium production rate in the breeding blankets of a fusion reactor

    International Nuclear Information System (INIS)

    In this work, a new passive technique has been developed for measuring the tritium production rate in ITER (International Thermonuclear Experimental Reactor) test blanket modules. This method is based on the secondary charged particle activation, in which the irradiated sample contains two main components: a tritium producing target (6Li or 7Li) and an indicator nuclide, which has a relatively high cross-section for an incoming tritium particle (triton). During the neutron irradiation, the target produces a triton, which has sufficiently high energy to cause the so-called secondary charged particle activation on an indicator nuclide. If the product of this reaction is a radioactive nuclide, its activity must be proportional to the amount of generated tritium. A comprehensive set of irradiations were performed at the Training Reactor of the Budapest University of Technology and Economics. The following charged particle reactions were observed and investigated: 27Al(t,p)29Al; 26Mg(t,p)28Mg; 26Mg(t,n)28Al; 32S(t,n)34mCl; 16O(t,n)18F; and 18O(t,α)17N. The optimal atomic ratio of the indicator elements and 6Li was also investigated. The reaction rates were estimated using calculations with the MCNPX Monte Carlo particle transport code. The trend of the measured and the simulated data are in good agreement, although accurate data for triton induced reaction cross-sections cannot be found in the literature. Once the technique is calibrated with a reference LSC (Liquid Scintillation Counting) measurement, a new passive method becomes available for tritium production rate measurements.

  2. Calculation of RBE for normal tissue complications based on charged particle track structure

    International Nuclear Information System (INIS)

    A new approach for the calculation of RBE for normal tissue complications after charged particle and neutron irradiation is discussed. It is based on the extension of a model originally developed for the application to cell survival. It can be shown, that according to the model RBE values are determined largely by the α/β-ratio of the photon dose response curve, but are expected to be nearly independent of the absolute values of α and β. Thus, the model can be applied to normal tissue complications as well, where α/β-ratios can be determined by means of fractionation experiments. Agreement of model predictions and experimental results obtained in animal experiments confirm the appliability of the model even in the case of complex biological endpoints. (orig.)

  3. Alterations of CNS structure & function by charged particle radiation & resultant oxidative stress

    Science.gov (United States)

    Nelson, Gregory; Chang, Polly; Favre, Cecile; Fike, John; Komarova, Natalia; Limoli, Charles; Mao, Xiao-Wen; Obenaus, Andre; Raber, Jacob; Spigelman, Igor; Soltesz, Ivan; Song, Sheng-Kwei; Stampanoni, Marco; Vlkolinsky, Roman; Wodarz, Dominik

    The NSCOR program project is transitioning from establishing the existence of CNS responses to low doses of charged particles, to an investigation of mechanisms underlying these changes and extending the irradiation paradigm to more space-like exposures. In earlier experiments we examined radiation responses of the mouse brain (hippocampus) following exposure to 250 MeV protons and 600 MeV/n iron ions. Our key findings on structural changes were: 1) Significant dose and time dependent loss of en-dothelial cells and microvessel network remodeling occurs suggesting that vascular insufficiency is produced. 2) Significant dose dependent losses of neural precursor cells were observed in a lineage specific pattern which may be associated with cognitive impairment. 3) Evaluation of DNA damage showed dose and time dependent accumulation of mutations with region-specific mutation structures and gene expression profiling demonstrated activation of neurotrophic and adhesion factors as well as chemokine receptors associated with inflammation. Our key find-ings on functional changes were: 1) Time and dose dependent modifications to neural output expressed as enhanced excitability but reduced synaptic efficacy and plasticity (including long term potentiation). 2) Intrinsic membrane properties of neurons were not significantly modi-fied by radiation exposure but pharmacological treatments demonstrated changes in inhibitory synapses. 3) MRI imaging visualized brain structural changes based on altered water diffu-sion properties and patterns were consistent with demyelination or gliosis. Our key findings on neurodegeneration and fidelity of homeostasis were: 1) APP23 transgenic mice exhibited accelerated APP-type electrophysiological pathology over several months. 2) Microvessel net-work changes following irradiation were suggestive of poor tissue oxygenation. 3) The ability of the brain to respond a controlled septic shock was altered by irradiation; the septic shock reactions

  4. Secondary charged particle spectra arising from 14 MeV neutrons

    International Nuclear Information System (INIS)

    This report presents the energy spectra of the charged secondaries arising in a few media under 14 MeV neutron irradiation. Six media are considered. They are C, N, O, CO2, air and soft tissue. The alpha particles and recoiling nuclei due to (n, alpha) events and the recoils produced in elastic and inelastic scattering events are considered in detail. The different excitation levels in which the recoiling nuclei may be left and also their anisotropic angular distributions are taken into account. A total of 43 individual reactions in C, N, and O are considered and five additional reactions could not be included for want of adequate data. Dose- and fluence-average LET's and average energy of these recoils are obtained from the calculated spectra. (author)

  5. Kinetic phenomena in charged particle transport in gases and plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, Zoran Lj.; Dujko, Sasa; Sasic, Olivera; Stojanovic, Vladimir; Malovic, Gordana [Institute of Physics, University of Belgrade, POB 68 11080 Zemun (Serbia); Faculty of Traffic Engineering, University of Belgrade Belgrade (Serbia); Institute of Physics, University of Belgrade, POB 68 11080 Zemun (Serbia)

    2012-05-25

    The key difference between equilibrium (thermal) and non-equilibrium (low temperature - a.k.a. cold) plasmas is in the degree in which the shape of the cross sections influences the electron energy distribution function (EEDF). In this paper we will discuss the issue of kinetic phenomena from two different angles. The first will be how to take advantage of the strong influence and use low current data to obtain the cross sections. This is also known as the swarm technique and the product of a ''swarm analysis'' is a set of cross sections giving good number, momentum and energy balances of electrons or other charged particles. At the same time understanding the EEDF is based on the cross section data. Nevertheless sometimes the knowledge of the cross sections and even the behaviour of individual particles are insufficient to explain collective behaviour of the ensemble. The resulting ''kinetic'' effects may be used to favour certain properties of non-equilibrium plasmas and even may be used as the basis of some new plasma applications.

  6. MEASUREMENTS OF A STEEL CHARGE EMISSIVITY UNDER STRONG IRRADIANCE CONDITIONS

    Directory of Open Access Journals (Sweden)

    Agnieszka Benduch

    2014-09-01

    Full Text Available Steel bars are manufactured in the rolling process, whereby they are characterized by strain hardening and poor plastic properties. In many application cases such properties are improper, therefore, additional heat treatment is required. Crucial influence on the products quality after heat treatment has an appropriate selection of process parameters. In many modern technologies of heat treatment the charge of porous structure is subjected to the heating process. Proper control of heat treatment parameters of bundles of rods requires knowledge on their thermal properties. However, it also requires accurate identification of complex heat transfer processes occurring in the porous material. Such analysis, with respect to bundles of bars, provide a response of qualitative nature of the heat exchange area of these charges. The article describes the emissivity measurements of samples of the steel charge using a thermal imaging camera.

  7. High Energy Ionic Charge State Composition in Large Solar Energetic Particle Events

    OpenAIRE

    Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Cummings, A. C.; Stone, E. C.; von Rosenvinge, T. T.

    2001-01-01

    Measurements of ionic charge states in solar energetic particle (SEP) events have been made at relatively high energies (> 15 MeV/nucleon) with the Mass Spectrometer Telescope (MAST) on board the Solar, Anomalous, and Magnetospheric Particle Explorer (SAMPEX) satellite using the Earth's magnetic field as a particle rigidity filter. We have examined the largest SEP events of solar cycle 23 and determined ionic charge states of Fe and other elements in several of these events. The mean charge s...

  8. Nonrelativistic Charged Particle-Magnetic Monopole Scattering in the Global Monopole Background

    CERN Document Server

    De Oliveira, A L C

    2003-01-01

    We analyze the nonrelativistic quantum scattering problem of a charged particle by an Abelian magnetic monopole in the background of a global monopole. In addition to the magnetic and geometric effects, we consider the influence of the electrostatic self-interaction on the charged particle. Moreover, for the specific case where the electrostatic self-interaction becomes attractive, charged particle-monopole bound system can be formed and the respective energy spectrum is hydrogen-like one.

  9. Surface-integral formulation of scattering theory for charged particles

    International Nuclear Information System (INIS)

    Full text: Collisions in the realm of atomic and nuclear physics not only have many practical applications, but also form the testing ground for the underlying quantum collision theory. The last decade has seen extraordinary theoretical progress in the field of electron-impact atomic breakup problem [1]. This problem was challenging to solve due to formal and computational difficulties associated with the long-range Coulomb potential. Presently, however, the electron-induced breakup processes can be calculated accurately for simple targets such as atomic hydrogen and helium, in the kinematically complete form. We report on how the computational progress has resulted in a deeper understanding of the formal theory of Coulomb few-body scattering [2] and how corresponding calculations of nuclear breakup reactions can benefit from this development. In quantum collision theory it is customary to define the scattering amplitude in terms of the scattering wave function and the potential of interaction. Despite the fact that the Coulomb wave function and the Coulomb potential are both known analytically, the conventional theory is not able to provide such a standard definition for the amplitude of scattering of two charged particles, which yields the Rutherford cross section. As far as breakup of a bound state of two particles in a system of three charged particles is concerned, here again the theory fails to give a formal definition for calculating the breakup amplitude in the post form in terms of the total scattering wave function describing the process. The reason for this failure is that charged particles continue to interact with each other even at infinite separation due to the long-range nature of the Coulomb potential, something the conventional theory cannot handle. We present a new formulation of scattering theory applicable to arbitrary two and three-body systems with both short-range and Coulomb long-range potentials [2]. The formalism is based on a surface

  10. History of activation analysis technique with charged particles in Uzbekistan

    International Nuclear Information System (INIS)

    Full text: The researches on activation analysis with charged particles (CPAA) were started immediately after beginning of constructing of 150-cm cyclotron U-150 in 60-th years of last century. CPAA laboratory organized on bases of the cyclotron and neutron generator NG-200 (in following I-150) in 1971 existed up to the end of 1985. We have used Ion beams of these devices to elaborate two types of nuclear analysis techniques: 1. Delayed Nuclear Analysis (DNA) involving Charged Particle Activation Analysis (CPAA) and Fast Neutron Activation Analysis (FNAA); 2. Prompt Nuclear Analysis (PNA) involving the spectrometry of particles induced X-Ray emission (PIXE). DNA with using accelerators has the following subdivisions: 1. Proton Activation Analysis (PAA); 2. Deuteron Activation Analysis (DAA); 3. 3He Activation Analysis (3HeAA); 4. 4He Activation Analysis (4HeAA or α-AA); 5. Fast Neutron Activation Analysis (FNAA). PAA and DAA found wide application were used to derive a good sensitivity in determination of contents of more than 20 chemical elements in some materials of high purity. For example, we have applied these techniques for the determination of Li, B, C, N, O, F at level of 10-8 - 10-10 g/g in different high purity semiconductors (Si, SiC, Ge, AsGa, InP et al.), nonferrous metals (Li, Be, Zr, Nb, Mo, Ta, W, Re, Al, Ti etc.), nonconductive materials (different glasses, optical materials, diamonds et al.) and environmental objects (soil, plants, water). The techniques provided good results on the determination of B, C and N contents and others. 3HeAA and 4HeAA were generally used to determine of O and C contents in semiconductors ands metals of high purity. We have elaborated rapid radiochemical techniques for separation of short-lived positron emitters. For example, the separation of 15O, formatting by nuclear reaction 16O(3He,α)15O, the reducing fusion technique was used. Radionuclide 11C was separated chemically by the oxidisation of samples in the

  11. Planar charged-particle trajectories in multipole magnetic fields

    Directory of Open Access Journals (Sweden)

    D. M. Willis

    Full Text Available This paper provides a complete generalization of the classic result that the radius of curvature (ρ of a charged-particle trajectory confined to the equatorial plane of a magnetic dipole is directly proportional to the cube of the particle's equatorial distance (ϖ from the dipole (i.e. ρ ∝ ϖ3. Comparable results are derived for the radii of curvature of all possible planar charged-particle trajectories in an individual static magnetic multipole of arbitrary order m and degree n. Such trajectories arise wherever there exists a plane (or planes such that the multipole magnetic field is locally perpendicular to this plane (or planes, everywhere apart from possibly at a set of magnetic neutral lines. Therefore planar trajectories exist in the equatorial plane of an axisymmetric (m = 0, or zonal, magnetic multipole, provided n is odd: the radius of curvature varies directly as ϖn+2. This result reduces to the classic one in the case of a zonal magnetic dipole (n =1. Planar trajectories exist in 2m meridional planes in the case of the general tesseral (0 < m < n magnetic multipole. These meridional planes are defined by the 2m roots of the equation cos[m(ΦΦnm] = 0, where Φnm = (1/m arctan (hnm/gnm; gnm and hnm denote the spherical harmonic coefficients. Equatorial planar trajectories also exist if (nm is odd. The polar axis (θ = 0,π of a tesseral magnetic multipole is a magnetic neutral line if m > 1. A further 2m(nm neutral lines exist at the intersections of the 2m meridional planes with the (nm cones defined by the (n

  12. The steady state of a particle in a vibrating box and possible application in short pulse generation of charged particles

    Indian Academy of Sciences (India)

    Nandan Jha; Sudhir R Jain

    2013-09-01

    In this paper the classical evolution of a particle is studied which bounces back and forth in a 1D vibrating cavity such that the reflection from the wall does not change the speed of the particle. A peculiar behaviour of the particle motion can be seen where the time evolution of the motion shows superposition of linear and oscillatory behaviour. In particular, the parameter range is found in which the particle oscillates between the walls in steady state as if the wall was static and it is showed that for these parameter ranges the particle settles to this steady state for all initial conditions. It is proposed that this phenomenon can be used to bunch charged particles in short pulses where the synchronization proposed in our model should work against the space charge effect in the charged particle bunch.

  13. Charged Particle Energization and Transport in Reservoirs throughout the Heliosphere: 1. Solar Energetic Particles

    Science.gov (United States)

    Roelof, E. C.

    2015-09-01

    “Reservoirs” of energetic charged particles are regions where the particle population is quasi-trapped in large-scale (relative to the gyroradii) magnetic field structures. Reservoirs are found throughout the heliosphere: the huge heliosheath (90appropriate description of this transport is “weak scattering”, in which the particle's first adiabatic invariant (magnetic moment) is approximately conserved while the particle itself moves rather freely along magnetic field lines. Considerable insight into the observed properties of energization processes can be gained from a remarkably simple equation that describes the particle's fractional time-rate-of-change of momentum (dlnp/dt) which depends only upon its pitch angle, the divergence of the plasma velocity (V⊥) transverse to the magnetic field), and the inner product of (V⊥) with the curvature vector of the field lines. The possibilities encompassed in this simple (but general) equation are quite rich, so we restrict our application of it in this paper to the compressive acceleration of SEPs within CMEs.

  14. Square-root operator quantization of elementary particles masses and charges

    International Nuclear Information System (INIS)

    Quantization of elementary particles masses and charges is proposed within the framework of the square-root operator formalism and the concept of extended particles associated with the structure of the torus. (author)

  15. Thermoluminescence of europium-doped zinc oxide exposed to beta particle irradiation

    International Nuclear Information System (INIS)

    Full text: Zn O is a promising material for a range of optoelectronics applications, due to its direct wide band gap (Eg ∼3.3 eV at 300 K) and large exciton binding energy (60 MeV). Its applications include UV light emitters, varistors, surface acoustic wave devices, piezoelectric transducers, and chemical and gas sensing. Rare-earth activation of phosphors has long been seen as an effective process since coupling energy into the rare-earth-ion site, either by ionization, charge exchange or a resonance energy process, results in light production. It is reported that Europium modifies the response thermoluminescence (Tl) for pure zinc oxide, when is irradiated with X-ray, created a peak at 365 degrees C. In this work, Zn O:Eu phosphors were synthesized by a chemical method. Some samples were exposed to beta particle irradiation for doses ranging from 1 up to 100 Gy. Tl response as a function of dose is linear throughout the studied dose range. The glow curve exhibits three maxima, centered at 176, 279 and 340 degrees C. The reusability studies obtained after ten repeated cycles of annealing irradiation readout for the Zn O:Eu shows that the variation in the Tl response is ten percent and tends to stabilization. The results indicate that these new Zn O:Eu phosphors are promising detectors and dosimeters for beta radiation. The structural and morphological characterization was carried out by X-ray diffraction and scanning electron microscopy, respectively. (Author)

  16. NRX and NRU reactor research facilities and irradiation and examination charges

    International Nuclear Information System (INIS)

    This report details the irradiation and examination charges on the NRX and NRU reactors at the Chalk River Nuclear Labs. It describes the NRX and NRU research facilities available to external users. It describes the various experimental holes and loops available for research. It also outlines the method used to calculate the facilities charges and the procedure for applying to use the facilities as well as the billing procedures.

  17. MEASUREMENTS OF A STEEL CHARGE EMISSIVITY UNDER STRONG IRRADIANCE CONDITIONS

    OpenAIRE

    Agnieszka Benduch; Rafał Wyczółkowski

    2014-01-01

    Steel bars are manufactured in the rolling process, whereby they are characterized by strain hardening and poor plastic properties. In many application cases such properties are improper, therefore, additional heat treatment is required. Crucial influence on the products quality after heat treatment has an appropriate selection of process parameters. In many modern technologies of heat treatment the charge of porous structure is subjected to the heating process. Proper control of heat treatme...

  18. Intermediate regime of charged particle scattering in the field-reversal configuration

    Energy Technology Data Exchange (ETDEWEB)

    Shustov, P. I., E-mail: p.shustov@gmail.com; Yushkov, E. V. [Space Research Institute, RAS, Profsouznaya st., 84/32, GSP-7, 117997 Moscow (Russian Federation); Department of Physics, Moscow State University, 119992 Moscow (Russian Federation); Artemyev, A. V., E-mail: artemyev@iki.rssi.ru [Space Research Institute, RAS, Profsouznaya st., 84/32, GSP-7, 117997 Moscow (Russian Federation)

    2015-12-15

    In this paper, we investigate the charged particle scattering in the magnetic field configuration with stretched magnetic field lines. This scattering results from the violation of the adiabaticity of charged particle motion in the region with the strong gradient of the magnetic field. We consider the intermediate regime of charged particle dynamics, when the violation of the adiabaticity is significant enough, but particle motion is not chaotic. We demonstrate and describe the significant scattering of particles with large adiabatic invariants (magnetic moment). We discuss a possible application of obtained results for description of the peculiarities of pitch-angle diffusion of relativistic electrons in the Earth radiation belts.

  19. Method of producing weakly acidic cation exchange resin particles charged with uranyl ions

    Energy Technology Data Exchange (ETDEWEB)

    Abdelmonem, N.; Ringel, H.; Zimmer, E.

    1981-07-21

    Weakly acidic cationic ion exchange resin particles are charged with uranyl ions by contacting the particles step wise with aqueous uranyl nitrate solution at higher uranium concentrations from stage to stage. An alkaline medium is added to the uranyl nitrate solution in each stage to increase the successive pH values of the uranyl nitrate solution contacting the particles in dependence upon the uranium concentration effective for maximum charging of the particles with uranyl ions.

  20. New generation of monolithic active pixel sensors for charged particle detection

    International Nuclear Information System (INIS)

    Vertex detectors are of great importance in particle physics experiments, as the knowledge of the event flavour is becoming an issue for the physics programme at Future Linear Colliders. Monolithic Active Pixel Sensors (MAPS) based on a novel detector structure have been proposed. Their fabrication is compatible with a standard CMOS process. The sensor is inseparable from the readout electronics, since both of them are integrated on the same, low-resistivity silicon wafer. The basic pixel configuration comprises only three MOS transistors and a diode collecting the charge through thermal diffusion. The charge is generated in the thin non-depleted epitaxial layer underneath the readout electronics. This approach provides, at low cost, a high resolution and thin device with the whole area sensitive to radiation. Device simulations using the ISE-TCAD package have been carried out to study the charge collection mechanism. In order to demonstrate the viability of the technique, four prototype chips have been fabricated using different submicrometer CMOS processes. The pixel gain has been calibrated using a 55Fe source and the Poisson sequence method. The prototypes have been exposed to high-energy particle beams at CERN. The tests proved excellent detection performances expressed in a single-track spatial resolution of 1.5 μm and detection efficiency close to 100%, resulting from a SNR ratio of more than 30. Irradiation tests showed immunity of MAPS to a level of a few times 1012 n/cm2 and a few hundred kRad of ionising radiation. The ideas for future work, including on-pixel signal amplification, double sampling operation and current mode pixel design are present as well. (author)

  1. Double electron excitation of helium by charged particle impact

    International Nuclear Information System (INIS)

    Complete text of publication follows. A four-body classical trajectory Monte Carlo method is applied in the study of double electron excitation of helium by charged particle impact. The calculations are based on the independent particle model. As projectiles we consider protons and antiprotons with energies between 0.25 and 5 MeV. The state selective total cross sections as a function of the impact energy are calculated and compared with experimental and theoretical data. Fig. 1. shows the double excitation cross sections of helium to the (2s2)1S (Fig. 1a), (2s2p)1P (Fig. 1b) and (2p2)1D (Fig. 1c) states as a function of the impact energy. The errors of our calculated data are smaller or comparable with the size of the symbols. Our recent cross sections are compared with the experimental data of Giese et al. and Moretto-Capelle et al. and with the previous calculations of Bodea et al. Instead of the antiproton impact, the experiments in ref. were carried out with electron impact. These cross sections are shown at the energy where the electron velocity is equal that of the antiproton velocity. In all cases the cross sections for antiprotons exceeds the cross section for protons. The largest difference is obtained for the excitation of the (2s2)1S state (Fig. 1a). According to our expectation, with increasing projectile energies the cross sections for proton and antiproton impact approaching each other. This tendency is valid for the previous calculations of Bodea et al. except for the (2p2)1D (Fig. 1c). The calculated cross sections generally agree with the experimental values. (author)

  2. Study on cytotoxicities induced by alpha particle irradiation combined with NNK treatment

    International Nuclear Information System (INIS)

    Objective: To investigate cytotoxicities of alpha-particle irradiation combined with NNK treatment. Methods: Exponentially growing immortalized human bronchial epithelial cells were divided into normal control group (NC), alpha particle irradiation group (α), NNK administration group (NNK), NNK administration (100 μg/ml) followed by alpha particle irradiation group (NNK + α), and alphaparticle irradiation followed by NNK administration (100 μg/ml) group (α + NNK). Cell survival fractions were measured by cloning rate of low-density plating cell. Ethidium bromide and 2', 7'-dichlorofluorescein, fluorescent products of the membrane-permeable dyes hydroethine and 2', 7'-dichloroflurescindiacetate were used to monitor the inarticulate reactive oxygen species (ROS) . Damage to membrane permeability was evaluated through testing LDH activity in medium. Results: In the groups exposed to both alpha particles and NNK, the survival rates were significantly lower than that of the groups administrated with the same dose of alpha particles or NNK alone. The levels of intracellular ROS and the activity of LDH in medium were significantly higher than that of the groups administrated with the same dose of alpha particles or NNK alone. Subtracted the NNK effect, the survival rates of the groups received both alpha particle irradiation and NNK treatment were significantly lower than that of alpha particle irradiated only group. However, the intracellular ROS level and the activity of LDH in medium were significantly higher than that of alpha-particle irradiated only group. In addition, the survival rates of the cells in groups exposed to alpha particle irradiation followed by NNK administration were significantly lower than that of cells treated with NNK administration followed by alpha particle irradiation. Conclusions: Alpha particle irradiation and NNK administration had synergisticity in cytotoxicity, and furthermore different schedules of the administration resulted in

  3. Signal and charge collection efficiency of n-in-p strip detectors after mixed irradiation to HL-LHC fluences

    Science.gov (United States)

    Kuehn, Susanne; Barber, Thomas; Casse, Gianluigi; Dervan, Paul; Driewer, Adrian; Forshaw, Dean; Huse, Torkjell; Jakobs, Karl; Parzefall, Ulrich

    2013-12-01

    For the year 2020, an upgrade of the LHC with a factor ten increase in luminosity is planned. The resulting severe radiation doses for the ATLAS tracker demand extremely radiation tolerant detectors. In this study six planar n-in-p strip sensors produced by Hamamatsu Photonics were irradiated in consecutive irradiation steps with pions of 280 Mev/c, protons of 25 Mev/c and reactor neutrons resulting in a combined fluence of up to 3×1015 1 MeV neutron equivalent particles per square centimeter (neq /cm2). This particle composition and fluence corresponds to the qualification limit specified by the ATLAS experiment for the outer pixel layers (assuming an integrated luminosity of 3000 fb-1). The 320 μm thick devices are investigated using electrons from a 90Sr source. After each irradiation step both charge collection efficiency and noise measurements have been performed using the ALIBAVA readout system, which is based on analogue Beetle ASICs clocked at 40 MHz. Measurements of the signal and signal-to-noise ratio of detectors will be given after the sensors were exposed to radiation that both in fluence and composition are corresponding to the expectations for the HL-LHC trackers. Conclusions will be drawn on their operation in the ATLAS inner detector upgrade.

  4. Magnetoinduction converter for measuring the charged particle flux in beams

    International Nuclear Information System (INIS)

    The arrangement of a contactless magnetoinduction converter (MIC) designed for measuring the charged particle flux in beams is described. The converter is made of a coil placed onto a toroidal ferromagnetic core, 120x60x12 mm in size. To eliminate the effect of the external magnetic field the MIC is placed into a compound permalloy- copper labyrinth-type screen, In the aperiodic operating mode the MIC measuring channel contains a preamplifier, an amplifier, a strobing circuit, an integrator with a converter, a delay circuit, a time relay, a pulsed-to-direct voltage converter, and a digital voltmeter. For experimental measuring of sensitivity of the MIC measuring system a calibration loop, consisting of an accurate- amplitude generator, a delay circuit and a time relay, is used. The given contactless magnetoinduction converter is a part of the electron flux standard for 5-50 MeV beams. The normal conditions of reproduction of the ''electron/s'' unit are the following: the 293+-1 K temperature, 101.3+40 kPa pressure, 60+-15% relative humidity, 220B+-10% supply voltage and 50+-0.5 Hz frequency. The dynamic range of MIC application is 1012-1015 electron/s. The total systematic error of reproduction of the electron flux unit for the MIC is 1.7%

  5. The Boltzmann equation theory of charged particle transport

    International Nuclear Information System (INIS)

    It is shown how a formally exact Kubo-like response theory equivalent to the Boltzmann equation theory of charged particle transport can be constructed. The response theory gives the general wavevector and time-dependent velocity distribution at any time in terms of an initial distribution function, to which is added the response induced by a generalized perturbation over the intervening time. The usual Kubo linear response result for the distribution function is recovered by choosing the initial velocity distribution to be Maxwellian. For completeness the response theory introduces an exponential convergence function into the response time integral. This is equivalent to using a modified Boltzmann equation but the general form of the transport theory is not changed. The modified transport theory can be used to advantage where possible convergence difficulties occur in numerical solutions of the Boltzmann equation. This paper gives a systematic development of the modified transport theory and shows how the response theory fits into the broader scheme of solving the Boltzmann equation. The discussion extends both the work of Kumar et al. (1980), where the distribution function is expanded out in terms of tensor functions, and the propagator description where the non-hydrodynamic time development of the distribution function is related to the wavevector dependent Green function of the Boltzmann equation

  6. Characterisation of charging kinetics of dielectrics under continuous electron irradiation through real time electron emission collecting method

    Energy Technology Data Exchange (ETDEWEB)

    Guerch, Kévin, E-mail: kevin.guerch@onera.fr [ONERA, 2 Avenue Edouard Belin, 31055 Toulouse Cedex 4 (France); CIRIMAT – Institut Carnot (CNRS) Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 09 (France); Paulmier, Thierry [ONERA, 2 Avenue Edouard Belin, 31055 Toulouse Cedex 4 (France); Guillemet-Fritsch, Sophie; Lenormand, Pascal [CIRIMAT – Institut Carnot (CNRS) Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse Cedex 09 (France)

    2015-04-15

    Dielectric materials used for spacecraft applications are often characterised under electron irradiation in order to study their physical and electrical mechanisms. For surface potential measurement, a small removable flat device based on the secondary electron spectrometer method has been developed and installed in the CEDRE irradiation test facility at ONERA (Toulouse, France). This technique was developed to get rid off specific issues inherent to the Kelvin Probe technique. This experimental device named REPA (Repulsive Electron Potential Analyser) allows in situ and real time assessment of the surface potential built up on dielectric materials under continuous electron irradiation. A calibration has been performed in order to validate this experimental setup. Furthermore, to optimise its efficiency, the physical behaviour of this device has been modelled and numerically simulated using Particle In Cell (PIC) model and a dedicated numerical code called SPIS (Spacecraft Plasma Interactions System). In a final step, electrical characterisations of a charged dielectric have been carried out under continuous electron irradiation with this new method. These results have been compared with measurements performed in same experimental conditions with conventional Kelvin Probe method. The experimental results have been discussed in this paper. To conclude, advantages of this experimental setup in regard of this application will be emphasised.

  7. Characterisation of charging kinetics of dielectrics under continuous electron irradiation through real time electron emission collecting method

    Science.gov (United States)

    Guerch, Kévin; Paulmier, Thierry; Guillemet-Fritsch, Sophie; Lenormand, Pascal

    2015-04-01

    Dielectric materials used for spacecraft applications are often characterised under electron irradiation in order to study their physical and electrical mechanisms. For surface potential measurement, a small removable flat device based on the secondary electron spectrometer method has been developed and installed in the CEDRE irradiation test facility at ONERA (Toulouse, France). This technique was developed to get rid off specific issues inherent to the Kelvin Probe technique. This experimental device named REPA (Repulsive Electron Potential Analyser) allows in situ and real time assessment of the surface potential built up on dielectric materials under continuous electron irradiation. A calibration has been performed in order to validate this experimental setup. Furthermore, to optimise its efficiency, the physical behaviour of this device has been modelled and numerically simulated using Particle In Cell (PIC) model and a dedicated numerical code called SPIS (Spacecraft Plasma Interactions System). In a final step, electrical characterisations of a charged dielectric have been carried out under continuous electron irradiation with this new method. These results have been compared with measurements performed in same experimental conditions with conventional Kelvin Probe method. The experimental results have been discussed in this paper. To conclude, advantages of this experimental setup in regard of this application will be emphasised.

  8. Charged particle therapy with mini-segmented beams

    Directory of Open Access Journals (Sweden)

    F. Avraham eDilmanian

    2015-12-01

    Full Text Available One of the fundamental attributes of proton therapy and carbon ion therapy is the ability of these charged particles to spare tissue distal to the targeted tumor. This significantly reduces normal tissue toxicity and has the potential to translate to a wider therapeutic index. Although, in general, particle therapy also reduces dose to the proximal tissues, particularly in the vicinity of the target, dose to the skin and to other very superficial tissues tends to be higher than that of megavoltage x-rays. The methods presented here, namely Interleaved carbon minibeams and Radiosurgery with arrays of proton and light ion minibeams, both utilize beams segmented into arrays of parallel minibeams of about 0.3 mm incident beam size. These minibeam arrays spare tissues, as demonstrated by synchrotron x-ray experiments. An additional feature of particle minibeams is their gradual broadening due to multiple Coulomb scattering as they penetrate tissues. In the case of interleaved carbon minibeams, which do not broaden much, two arrays of planar carbon minibeams that remain parallel at target depth, are aimed at the target from 90º angles and made to interleave at the target to produce a solid radiation field within the target. As a result the surrounding tissues are exposed only to individual carbon minibeam arrays and are therefore spared. The method was used in four-directional geometry at the NASA Space Radiation Laboratory to ablate a 6.5-mm target in a rabbit brain at a single exposure with 40 Gy physical absorbed dose. Contrast-enhanced magnetic resonance imaging and histology six month later showed very focal target necrosis with nearly no damage to the surrounding brain. As for minibeams of protons and light ions, for which the minibeam broadening is substantial, measurements at MD Anderson Cancer Center in Houston, Texas, and Monte Carlo simulations showed that the broadening minibeams will merge with their neighbors at a certain tissue depth

  9. Investigation of the charge collection for strongly irradiated silicon strip detectors of the CMS ECAL Preshower

    International Nuclear Information System (INIS)

    Strongly irradiated (2.3·1014 n/cm2) silicon strip detectors of different size, thickness and different design options were tested in a muon beam at CERN in 1999. A charge collection efficiency in excess of 85% and a signal-to-noise ratio of about 6 are obtained in all cases at high enough bias voltage. Details of the charge collection in the interstrip and the guard ring region and cross-talk between strips were also studied. We find that the charge collection efficiency and the cross-talk between strips depend on the interstrip distance

  10. Investigation of the charge collection for strongly irradiated Silicon strip detectors of the CMS ECAL Preshower

    CERN Document Server

    CERN. Geneva

    2000-01-01

    Strongly irradiated silicon strip detectors of different size, thickness and different design options were tested in a muon beam at CERN in 1999. A charge collection efficiency in excess of 85% and a signal to noise ratio of 6 are obtained in all cases at high enough bias voltage. Details of the charge collection in the inter-strip and the guard ring region and crosstalk between strips were also studied. We find that the charge collection efficiency and the cross talk between strips depend on the interstrip distance.

  11. Study of charge collection and noise in non-irradiated and irradiated silicon detectors

    CERN Document Server

    Leroy, C; Dezillie, B; Glaser, M; Lemeilleur, F; Trigger, I

    1996-01-01

    The large collection and noise were studied in non-irradiated and irradiated silicon detectors as a function of temperature (T), shaping time (0) and fluence , up to about 1,2 x 10(14) protons per cm2 for minimum-ionizing electrons yielded by a 106 Ru source. The noise of irradiated detectors is found to be dominted for short shaping times (¾50ns) by a series noise compo- nent, while for longer shaping times („80ns) a parallel noise component (correlated with the reverse current) prevails. For non-irradiated detectors, where the reverse current is three orders of magnetude smaller compared with irradiated detectors, the series noises dominates over the whole range of shaping times investigated (20-150ns). A signal degradation is observed for irradiated detectors. However, the signal ca be distinguished from noise, even after a fluence of about 1.2 x10(14) protons per cm2, at a temperature of 6øC and with a shaping time tipical of rge LHC inter-bunch crossing time (20-30ns). The measurements of the signal a...

  12. Theory of small-angle multiple scattering of charged particles with consideration of geometrical interfaces

    International Nuclear Information System (INIS)

    Applying the small-angle multiple scattering theory of Rossi and Greisen, especially the pencil-beam solution supplied by E. Fermi, we have solved two boundary surface problems of multiple scattering of electrons and other charged particles in the energy range of radiation therapy. In the validity range of the small-angle approximation, the number and the angular distribution of the scattered electrons leaving the lateral surface of an electron-irradiated absorber block have been correctly calculated. The essential step has been to find a continuous solution describing the transition from inner to outer space of the absorber. Furthermore, the phenomenon of 'quasi-reflexion', occurring when electrons are entering a boundary plane under a small entrance angle, has been correctly reproduced as an analytical result. The correctness of the analytical results was checked by comparison with a highly accurate, own Monte-Carlo program. We are planning to extend the theoretical treatment by considering large-angle scattering as well. In the framework of radiation therapy with electrons and hadrons, the present results can be applied to understand and quantitatively estimate the effects of 'in-scattering' into air-filled cavities of the irradiated body or of ionization chambers, of scattering at collimator edges and of 'quasi-reflexion' in the case of small-angle incidence into applicator cone walls. (orig.)

  13. The Current Status and Future Directions of Heavy Charged Particle Therapy in Medicine

    Science.gov (United States)

    Levy, Richard P.; Blakely, Eleanor A.; Chu, William T.; Coutrakon, George B.; Hug, Eugen B.; Kraft, Gerhard; Tsujii, Hirohiko

    2009-03-01

    As aggressive, 3D-conformal treatment has become the clearly accepted goal of radiation oncology, heavy charged-particle treatment with protons and heavier ions has concurrently and relentlessly ascended to the forefront. Protons and helium nuclei, with relatively low linear-energy-transfer (LET) properties, have consistently been demonstrated to be beneficial for aggressive (high-dose) local treatment of many types of tumors. Protons have been applied to the majority of solid tumors, and have reached a high degree of general acceptance in radiation oncology after three decades and 55,000 patients treated. However, some 15% to 20% of tumor types have proven resistant to even the most aggressive low-LET irradiation. For these radio-resistant tumors, treatment with heavier ions (e.g., carbon) offers great potential benefit. These high-LET particles have increased relative biological effectiveness (RBE) that reaches its maximum in the Bragg peak. Irradiation with these heavier ions offers the unique combination of excellent 3D-dose distribution and increased RBE. We are presently witnessing several, important parallel developments in particle therapy. Protons will likely continue their exponential growth phase, and more compact design systems will make protons available to a larger patient population—thus becoming the "heavy charged particle of choice" for Cancer Centers with limited financial resources. In parallel, major academic efforts will further advance the field of heavier ion therapy, exploring all opportunities for particle treatment and continuing the search for the ideal particle(s) for specific tumors. The future of ion therapy will be best realized by clinical trials that have ready access to top-quality delivery of both protons and heavier ions that can be accurately shaped for treatment of a specific pathology, and which will permit direct randomized-trial comparison of the effectiveness of the various ions for different diseases. Optimal results

  14. Dependence of plasmon excitation energy on filler material in interaction of charged particle with filled nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Bahari, A., E-mail: bahari.a@lu.ac.i [Department of Physics, Lorestan University, Lorestan (Iran, Islamic Republic of); Mohamadi, A. [Department of Physics, Shiraz Payaem Noor University, Fars (Iran, Islamic Republic of)

    2010-10-15

    The interaction of charged particles with filled single-walled metallic nanotubes (SWMNT) has been investigated. Numerical results for the plasmon energy as a function of the wave vector are presented when the charged particle is outside the nanotube. Dependence of the plasmon energy on ratio of plasma frequency of the filler and SWMNT has been shown.

  15. Summary report on first research coordination meeting on heavy charged-particle interaction data for radiotherapy

    International Nuclear Information System (INIS)

    A summary is given of the First Research Coordination Meeting on Heavy Charged-Particle Interaction Data for Radiotherapy. A programme to compile and evaluate charged-particle nuclear data for therapeutic applications was proposed. Detailed coordinated research proposals were also agreed. Technical discussions and the resulting work plan of the Coordinated Research Project are summarized, along with actions and deadlines. (author)

  16. Method and system for treating an interior surface of a workpiece using a charged particle beam

    Science.gov (United States)

    Swenson, David Richard

    2007-05-23

    A method and system of treating an interior surface on an internal cavity of a workpiece using a charged particle beam. A beam deflector surface of a beam deflector is placed within the internal cavity of the workpiece and is used to redirect the charged particle beam toward the interior surface to treat the interior surface.

  17. The influence of oxidation on space charge formation in gamma-irradiated low-density polyethylene

    CERN Document Server

    Chen, G; Xie, H K; Banford, H M; Davies, A E

    2003-01-01

    The research presented in this paper investigates the role of oxidation in the formation of space charge in gamma-irradiated low-density polyethylene after being electrically stressed under dc voltage. Polyethylene plaques both with and without antioxidant were irradiated up to 500 kGy using a sup 6 sup 0 Co gamma source and space charge distributions were measured using the piezoelectric induced pressure wave propagation method. It has been found that a large amount of positive charge evolved adjacent to the cathode in the sample without antioxidant and was clearly associated with oxidation of the surface. The amount of charge formed for a given applied stress increased with the dose absorbed by the material. A model has been proposed to explain the formation of space charge and its profile. The charge decay after the removal of the external applied stress is dominated by a process being controlled by the cathode interfacial stress (charge injection) rather than a conventional RC circuit model. On the other ...

  18. Magnetic relaxation processes in hydrogen-charged electron-irradiated Pd3Fe

    International Nuclear Information System (INIS)

    Ordered (L12) and disordered Pd3Fe is charged with hydrogen, both electrolytically and thermally, and then irradiated at about 40 K with 3 MeV electrons to a dose of 9.6 x 1022 m-2. A detailed investigation of the resulting magnetic relaxation spectra and their annealing behaviours is made. In ordered Pd3Fe, relaxation peaks are observed at 34 and 74 K; these are increased in amplitude over the corresponding peaks in irradiated, uncharged samples. This is attributed to the trapping of intrinsic defects at hydrogen. Apart from this, no significant difference is found from the relaxation spectra of hydrogen-charged, irradiated Pd3Fe. It is concluded that the interactions between hydrogen and radiation-induced defects in Pd3Fe are too small to produce any additional, measurable relaxation effects. (orig.)

  19. Influence of stresses on the mechanical properties of charged elastomers during their aging by irradiation

    International Nuclear Information System (INIS)

    The damage in time of materials can have determining consequences on their mechanical properties. The aim of this work is to study the aging by irradiation of charged elastomers, and more particularly of charged aluminium tri-hydrated ethylene propylene diene polymers (EPDM). The evolution of this type of materials submitted to a gamma irradiation aging in presence of oxygen is presented. The materials have been tested and characterized at different aging levels, chemical, microstructural and mechanical: here only the results for small deformations and big deformations (uniaxial traction) are presented. From these analyses, it has been revealed a competition between the reticulation/chains cleavages during irradiations and the particular influence of the stresses on the mechanical properties during aging. (O.M.)

  20. Charged NUT field : [Part] I. Motion of test particles and [Part] II. Cosmic censorship

    International Nuclear Information System (INIS)

    Some properties of the charged NUT field are studied. In the first part of the paper, some general aspects of the charged NUT field have been investigated using uncharged and charged particles. The behaviour of the particles near the singularity has also been considered. In the second part of the paper, the charged NUT sources in the context of cosmic censorship hypothesis are studied. Motion of charged particles in the equatorial plane and along the axis is considered. From this investigation the interesting result is discovered that by such a bombardment of charged test particles, the existing event horizons cannot be destroyed but, in contrast to the Reissner-Nordstrom field, naked singularities do not get enveloped by event horizons. (author)

  1. Search for fractionally charged particles in pp collisions at $\\sqrt{s}$ = 7 TeV

    CERN Document Server

    Chatrchyan, Serguei; Sirunyan, Albert M; Tumasyan, Armen; Adam, Wolfgang; Aguilo, Ernest; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; Ghete, Vasile Mihai; Hammer, Josef; Hörmann, Natascha; Hrubec, Josef; Jeitler, Manfred; Kiesenhofer, Wolfgang; Knünz, Valentin; Krammer, Manfred; Krätschmer, Ilse; Liko, Dietrich; Mikulec, Ivan; Pernicka, Manfred; Rahbaran, Babak; Rohringer, Christine; Rohringer, Herbert; Schöfbeck, Robert; Strauss, Josef; Taurok, Anton; Waltenberger, Wolfgang; Walzel, Gerhard; Widl, Edmund; Wulz, Claudia-Elisabeth; Mossolov, Vladimir; Shumeiko, Nikolai; Suarez Gonzalez, Juan; Bansal, Monika; Bansal, Sunil; Cornelis, Tom; De Wolf, Eddi A; Janssen, Xavier; Luyckx, Sten; Mucibello, Luca; Ochesanu, Silvia; Roland, Benoit; Rougny, Romain; Selvaggi, Michele; Staykova, Zlatka; Van Haevermaet, Hans; Van Mechelen, Pierre; Van Remortel, Nick; Van Spilbeeck, Alex; Blekman, Freya; Blyweert, Stijn; D'Hondt, Jorgen; Gonzalez Suarez, Rebeca; Kalogeropoulos, Alexis; Maes, Michael; Olbrechts, Annik; Van Doninck, Walter; Van Mulders, Petra; Van Onsem, Gerrit Patrick; Villella, Ilaria; Clerbaux, Barbara; De Lentdecker, Gilles; Dero, Vincent; Gay, Arnaud; Hreus, Tomas; Léonard, Alexandre; Marage, Pierre Edouard; Mohammadi, Abdollah; Reis, Thomas; Thomas, Laurent; Vander Marcken, Gil; Vander Velde, Catherine; Vanlaer, Pascal; Wang, Jian; Adler, Volker; Beernaert, Kelly; Cimmino, Anna; Costantini, Silvia; Garcia, Guillaume; Grunewald, Martin; Klein, Benjamin; Lellouch, Jérémie; Marinov, Andrey; Mccartin, Joseph; Ocampo Rios, Alberto Andres; Ryckbosch, Dirk; Strobbe, Nadja; Thyssen, Filip; Tytgat, Michael; Verwilligen, Piet; Walsh, Sinead; Yazgan, Efe; Zaganidis, Nicolas; Basegmez, Suzan; Bruno, Giacomo; Castello, Roberto; Ceard, Ludivine; Delaere, Christophe; Du Pree, Tristan; Favart, Denis; Forthomme, Laurent; Giammanco, Andrea; Hollar, Jonathan; Lemaitre, Vincent; Liao, Junhui; Militaru, Otilia; Nuttens, Claude; Pagano, Davide; Pin, Arnaud; Piotrzkowski, Krzysztof; Schul, Nicolas; Vizan Garcia, Jesus Manuel; Beliy, Nikita; Caebergs, Thierry; Daubie, Evelyne; Hammad, Gregory Habib; Alves, Gilvan; Correa Martins Junior, Marcos; De Jesus Damiao, Dilson; Martins, Thiago; Pol, Maria Elena; Henrique Gomes E Souza, Moacyr; Aldá Júnior, Walter Luiz; Carvalho, Wagner; Custódio, Analu; Da Costa, Eliza Melo; De Oliveira Martins, Carley; Fonseca De Souza, Sandro; Matos Figueiredo, Diego; Mundim, Luiz; Nogima, Helio; Oguri, Vitor; Prado Da Silva, Wanda Lucia; Santoro, Alberto; Soares Jorge, Luana; Sznajder, Andre; Souza Dos Anjos, Tiago; Bernardes, Cesar Augusto; De Almeida Dias, Flavia; Tomei, Thiago; De Moraes Gregores, Eduardo; Lagana, Caio; Da Cunha Marinho, Franciole; Mercadante, Pedro G; Novaes, Sergio F; Padula, Sandra; Genchev, Vladimir; Iaydjiev, Plamen; Piperov, Stefan; Rodozov, Mircho; Stoykova, Stefka; Sultanov, Georgi; Tcholakov, Vanio; Trayanov, Rumen; Vutova, Mariana; Dimitrov, Anton; Hadjiiska, Roumyana; Kozhuharov, Venelin; Litov, Leander; Pavlov, Borislav; Petkov, Peicho; Bian, Jian-Guo; Chen, Guo-Ming; Chen, He-Sheng; Jiang, Chun-Hua; Liang, Dong; Liang, Song; Meng, Xiangwei; Tao, Junquan; Wang, Jian; Wang, Xianyou; Wang, Zheng; Xiao, Hong; Xu, Ming; Zang, Jingjing; Zhang, Zhen; Asawatangtrakuldee, Chayanit; Ban, Yong; Guo, Yifei; Li, Wenbo; Liu, Shuai; Mao, Yajun; Qian, Si-Jin; Teng, Haiyun; Wang, Dayong; Zhang, Linlin; Zou, Wei; Avila, Carlos; Gomez, Juan Pablo; Gomez Moreno, Bernardo; Osorio Oliveros, Andres Felipe; Sanabria, Juan Carlos; Godinovic, Nikola; Lelas, Damir; Plestina, Roko; Polic, Dunja; Puljak, Ivica; Antunovic, Zeljko; Kovac, Marko; Brigljevic, Vuko; Duric, Senka; Kadija, Kreso; Luetic, Jelena; Morovic, Srecko; Attikis, Alexandros; Galanti, Mario; Mavromanolakis, Georgios; Mousa, Jehad; Nicolaou, Charalambos; Ptochos, Fotios; Razis, Panos A; Finger, Miroslav; Finger Jr, Michael; Assran, Yasser; Elgammal, Sherif; Ellithi Kamel, Ali; Khalil, Shaaban; Mahmoud, Mohammed; Radi, Amr; Kadastik, Mario; Müntel, Mait; Raidal, Martti; Rebane, Liis; Tiko, Andres; Eerola, Paula; Fedi, Giacomo; Voutilainen, Mikko; Härkönen, Jaakko; Heikkinen, Mika Aatos; Karimäki, Veikko; Kinnunen, Ritva; Kortelainen, Matti J; Lampén, Tapio; Lassila-Perini, Kati; Lehti, Sami; Lindén, Tomas; Luukka, Panja-Riina; Mäenpää, Teppo; Peltola, Timo; Tuominen, Eija; Tuominiemi, Jorma; Tuovinen, Esa; Ungaro, Donatella; Wendland, Lauri; Banzuzi, Kukka; Karjalainen, Ahti; Korpela, Arja; Tuuva, Tuure; Besancon, Marc; Choudhury, Somnath; Dejardin, Marc; Denegri, Daniel; Fabbro, Bernard; Faure, Jean-Louis; Ferri, Federico; Ganjour, Serguei; Givernaud, Alain; Gras, Philippe; Hamel de Monchenault, Gautier; Jarry, Patrick; Locci, Elizabeth; Malcles, Julie; Millischer, Laurent; Nayak, Aruna; Rander, John; Rosowsky, André; Shreyber, Irina; Titov, Maksym; Baffioni, Stephanie; Beaudette, Florian; Benhabib, Lamia; Bianchini, Lorenzo; Bluj, Michal; Broutin, Clementine; Busson, Philippe; Charlot, Claude; Daci, Nadir; Dahms, Torsten; Dobrzynski, Ludwik; Granier de Cassagnac, Raphael; Haguenauer, Maurice; Miné, Philippe; Mironov, Camelia; Naranjo, Ivo Nicolas; Nguyen, Matthew; Ochando, Christophe; Paganini, Pascal; Sabes, David; Salerno, Roberto; Sirois, Yves; Veelken, Christian; Zabi, Alexandre; Agram, Jean-Laurent; Andrea, Jeremy; Bloch, Daniel; Bodin, David; Brom, Jean-Marie; Cardaci, Marco; Chabert, Eric Christian; Collard, Caroline; Conte, Eric; Drouhin, Frédéric; Ferro, Cristina; Fontaine, Jean-Charles; Gelé, Denis; Goerlach, Ulrich; Juillot, Pierre; Le Bihan, Anne-Catherine; Van Hove, Pierre; Fassi, Farida; Mercier, Damien; Beauceron, Stephanie; Beaupere, Nicolas; Bondu, Olivier; Boudoul, Gaelle; Chasserat, Julien; Chierici, Roberto; Contardo, Didier; Depasse, Pierre; El Mamouni, Houmani; Fay, Jean; Gascon, Susan; Gouzevitch, Maxime; Ille, Bernard; Kurca, Tibor; Lethuillier, Morgan; Mirabito, Laurent; Perries, Stephane; Sgandurra, Louis; Sordini, Viola; Tschudi, Yohann; Verdier, Patrice; Viret, Sébastien; Tsamalaidze, Zviad; Anagnostou, Georgios; Autermann, Christian; Beranek, Sarah; Edelhoff, Matthias; Feld, Lutz; Heracleous, Natalie; Hindrichs, Otto; Jussen, Ruediger; Klein, Katja; Merz, Jennifer; Ostapchuk, Andrey; Perieanu, Adrian; Raupach, Frank; Sammet, Jan; Schael, Stefan; Sprenger, Daniel; Weber, Hendrik; Wittmer, Bruno; Zhukov, Valery; Ata, Metin; Caudron, Julien; Dietz-Laursonn, Erik; Duchardt, Deborah; Erdmann, Martin; Fischer, Robert; Güth, Andreas; Hebbeker, Thomas; Heidemann, Carsten; Hoepfner, Kerstin; Klingebiel, Dennis; Kreuzer, Peter; Merschmeyer, Markus; Meyer, Arnd; Olschewski, Mark; Papacz, Paul; Pieta, Holger; Reithler, Hans; Schmitz, Stefan Antonius; Sonnenschein, Lars; Steggemann, Jan; Teyssier, Daniel; Weber, Martin; Bontenackels, Michael; Cherepanov, Vladimir; Erdogan, Yusuf; Flügge, Günter; Geenen, Heiko; Geisler, Matthias; Haj Ahmad, Wael; Hoehle, Felix; Kargoll, Bastian; Kress, Thomas; Kuessel, Yvonne; Lingemann, Joschka; Nowack, Andreas; Perchalla, Lars; Pooth, Oliver; Sauerland, Philip; Stahl, Achim; Aldaya Martin, Maria; Behr, Joerg; Behrenhoff, Wolf; Behrens, Ulf; Bergholz, Matthias; Bethani, Agni; Borras, Kerstin; Burgmeier, Armin; Cakir, Altan; Calligaris, Luigi; Campbell, Alan; Castro, Elena; Costanza, Francesco; Dammann, Dirk; Diez Pardos, Carmen; Eckerlin, Guenter; Eckstein, Doris; Flucke, Gero; Geiser, Achim; Glushkov, Ivan; Gunnellini, Paolo; Habib, Shiraz; Hauk, Johannes; Hellwig, Gregor; Jung, Hannes; Kasemann, Matthias; Katsas, Panagiotis; Kleinwort, Claus; Kluge, Hannelies; Knutsson, Albert; Krämer, Mira; Krücker, Dirk; Kuznetsova, Ekaterina; Lange, Wolfgang; Lohmann, Wolfgang; Lutz, Benjamin; Mankel, Rainer; Marfin, Ihar; Marienfeld, Markus; Melzer-Pellmann, Isabell-Alissandra; Meyer, Andreas Bernhard; Mnich, Joachim; Mussgiller, Andreas; Naumann-Emme, Sebastian; Novgorodova, Olga; Olzem, Jan; Perrey, Hanno; Petrukhin, Alexey; Pitzl, Daniel; Raspereza, Alexei; Ribeiro Cipriano, Pedro M; Riedl, Caroline; Ron, Elias; Rosin, Michele; Salfeld-Nebgen, Jakob; Schmidt, Ringo; Schoerner-Sadenius, Thomas; Sen, Niladri; Spiridonov, Alexander; Stein, Matthias; Walsh, Roberval; Wissing, Christoph; Blobel, Volker; Draeger, Jula; Enderle, Holger; Erfle, Joachim; Gebbert, Ulla; Görner, Martin; Hermanns, Thomas; Höing, Rebekka Sophie; Kaschube, Kolja; Kaussen, Gordon; Kirschenmann, Henning; Klanner, Robert; Lange, Jörn; Mura, Benedikt; Nowak, Friederike; Peiffer, Thomas; Pietsch, Niklas; Rathjens, Denis; Sander, Christian; Schettler, Hannes; Schleper, Peter; Schlieckau, Eike; Schmidt, Alexander; Schröder, Matthias; Schum, Torben; Seidel, Markus; Sola, Valentina; Stadie, Hartmut; Steinbrück, Georg; Thomsen, Jan; Vanelderen, Lukas; Barth, Christian; Berger, Joram; Böser, Christian; Chwalek, Thorsten; De Boer, Wim; Descroix, Alexis; Dierlamm, Alexander; Feindt, Michael; Guthoff, Moritz; Hackstein, Christoph; Hartmann, Frank; Hauth, Thomas; Heinrich, Michael; Held, Hauke; Hoffmann, Karl-Heinz; Husemann, Ulrich; Katkov, Igor; Komaragiri, Jyothsna Rani; Lobelle Pardo, Patricia; Martschei, Daniel; Mueller, Steffen; Müller, Thomas; Niegel, Martin; Nürnberg, Andreas; Oberst, Oliver; Oehler, Andreas; Ott, Jochen; Quast, Gunter; Rabbertz, Klaus; Ratnikov, Fedor; Ratnikova, Natalia; Röcker, Steffen; Schilling, Frank-Peter; Schott, Gregory; Simonis, Hans-Jürgen; Stober, Fred-Markus Helmut; Troendle, Daniel; Ulrich, Ralf; Wagner-Kuhr, Jeannine; Wayand, Stefan; Weiler, Thomas; Zeise, Manuel; Daskalakis, Georgios; Geralis, Theodoros; Kesisoglou, Stilianos; Kyriakis, Aristotelis; Loukas, Demetrios; Manolakos, Ioannis; Markou, Athanasios; Markou, Christos; Mavrommatis, Charalampos; Ntomari, Eleni; Gouskos, Loukas; Mertzimekis, Theodoros; Panagiotou, Apostolos; Saoulidou, Niki; Evangelou, Ioannis; Foudas, Costas; Kokkas, Panagiotis; Manthos, Nikolaos; Papadopoulos, Ioannis; Patras, Vaios; Bencze, Gyorgy; Hajdu, Csaba; Hidas, Pàl; Horvath, Dezso; Sikler, Ferenc; Veszpremi, Viktor; Vesztergombi, Gyorgy; Beni, Noemi; Czellar, Sandor; Molnar, Jozsef; Palinkas, Jozsef; Szillasi, Zoltan; Karancsi, János; Raics, Peter; Trocsanyi, Zoltan Laszlo; Ujvari, Balazs; Beri, Suman Bala; Bhatnagar, Vipin; Dhingra, Nitish; Gupta, Ruchi; Kaur, Manjit; Mehta, Manuk Zubin; Nishu, Nishu; Saini, Lovedeep Kaur; Sharma, Archana; Singh, Jasbir; Kumar, Ashok; Kumar, Arun; Ahuja, Sudha; Bhardwaj, Ashutosh; Choudhary, Brajesh C; Malhotra, Shivali; Naimuddin, Md; Ranjan, Kirti; Sharma, Varun; Shivpuri, Ram Krishen; Banerjee, Sunanda; Bhattacharya, Satyaki; Dutta, Suchandra; Gomber, Bhawna; Jain, Sandhya; Jain, Shilpi; Khurana, Raman; Sarkar, Subir; Sharan, Manoj; Abdulsalam, Abdulla; Choudhury, Rajani Kant; Dutta, Dipanwita; Kailas, Swaminathan; Kumar, Vineet; Mehta, Pourus; Mohanty, Ajit Kumar; Pant, Lalit Mohan; Shukla, Prashant; Aziz, Tariq; Ganguly, Sanmay; Guchait, Monoranjan; Maity, Manas; Majumder, Gobinda; Mazumdar, Kajari; Mohanty, Gagan Bihari; Parida, Bibhuti; Sudhakar, Katta; Wickramage, Nadeesha; Banerjee, Sudeshna; Dugad, Shashikant; Arfaei, Hessamaddin; Bakhshiansohi, Hamed; Etesami, Seyed Mohsen; Fahim, Ali; Hashemi, Majid; Hesari, Hoda; Jafari, Abideh; Khakzad, Mohsen; Mohammadi Najafabadi, Mojtaba; Paktinat Mehdiabadi, Saeid; Safarzadeh, Batool; Zeinali, Maryam; Abbrescia, Marcello; Barbone, Lucia; Calabria, Cesare; Chhibra, Simranjit Singh; Colaleo, Anna; Creanza, Donato; De Filippis, Nicola; De Palma, Mauro; Fiore, Luigi; Iaselli, Giuseppe; Lusito, Letizia; Maggi, Giorgio; Maggi, Marcello; Marangelli, Bartolomeo; My, Salvatore; Nuzzo, Salvatore; Pacifico, Nicola; Pompili, Alexis; Pugliese, Gabriella; Selvaggi, Giovanna; Silvestris, Lucia; Singh, Gurpreet; Venditti, Rosamaria; Zito, Giuseppe; Abbiendi, Giovanni; Benvenuti, Alberto; Bonacorsi, Daniele; Braibant-Giacomelli, Sylvie; Brigliadori, Luca; Capiluppi, Paolo; Castro, Andrea; Cavallo, Francesca Romana; Cuffiani, Marco; Dallavalle, Gaetano-Marco; Fabbri, Fabrizio; Fanfani, Alessandra; Fasanella, Daniele; Giacomelli, Paolo; Grandi, Claudio; Guiducci, Luigi; Marcellini, Stefano; Masetti, Gianni; Meneghelli, Marco; Montanari, Alessandro; Navarria, Francesco; Odorici, Fabrizio; Perrotta, Andrea; Primavera, Federica; Rossi, Antonio; Rovelli, Tiziano; Siroli, Gian Piero; Travaglini, Riccardo; Albergo, Sebastiano; Cappello, Gigi; Chiorboli, Massimiliano; Costa, Salvatore; Potenza, Renato; Tricomi, Alessia; Tuve, Cristina; Barbagli, Giuseppe; Ciulli, Vitaliano; Civinini, Carlo; D'Alessandro, Raffaello; Focardi, Ettore; Frosali, Simone; Gallo, Elisabetta; Gonzi, Sandro; Meschini, Marco; Paoletti, Simone; Sguazzoni, Giacomo; Tropiano, Antonio; Benussi, Luigi; Bianco, Stefano; Colafranceschi, Stefano; Fabbri, Franco; Piccolo, Davide; Fabbricatore, Pasquale; Musenich, Riccardo; Tosi, Silvano; Benaglia, Andrea; De Guio, Federico; Di Matteo, Leonardo; Fiorendi, Sara; Gennai, Simone; Ghezzi, Alessio; Malvezzi, Sandra; Manzoni, Riccardo Andrea; Martelli, Arabella; Massironi, Andrea; Menasce, Dario; Moroni, Luigi; Paganoni, Marco; Pedrini, Daniele; Ragazzi, Stefano; Redaelli, Nicola; Sala, Silvano; Tabarelli de Fatis, Tommaso; Buontempo, Salvatore; Carrillo Montoya, Camilo Andres; Cavallo, Nicola; De Cosa, Annapaola; Dogangun, Oktay; Fabozzi, Francesco; Iorio, Alberto Orso Maria; Lista, Luca; Meola, Sabino; Merola, Mario; Paolucci, Pierluigi; Azzi, Patrizia; Bacchetta, Nicola; Bisello, Dario; Branca, Antonio; Carlin, Roberto; Checchia, Paolo; Dorigo, Tommaso; Gasparini, Fabrizio; Gasparini, Ugo; Gozzelino, Andrea; Kanishchev, Konstantin; Lacaprara, Stefano; Lazzizzera, Ignazio; Margoni, Martino; Meneguzzo, Anna Teresa; Pazzini, Jacopo; Pozzobon, Nicola; Ronchese, Paolo; Simonetto, Franco; Torassa, Ezio; Tosi, Mia; Vanini, Sara; Zotto, Pierluigi; Zucchetta, Alberto; Zumerle, Gianni; Gabusi, Michele; Ratti, Sergio P; Riccardi, Cristina; Torre, Paola; Vitulo, Paolo; Biasini, Maurizio; Bilei, Gian Mario; Fanò, Livio; Lariccia, Paolo; Mantovani, Giancarlo; Menichelli, Mauro; Nappi, Aniello; Romeo, Francesco; Saha, Anirban; Santocchia, Attilio; Spiezia, Aniello; Taroni, Silvia; Azzurri, Paolo; Bagliesi, Giuseppe; Bernardini, Jacopo; Boccali, Tommaso; Broccolo, Giuseppe; Castaldi, Rino; D'Agnolo, Raffaele Tito; Dell'Orso, Roberto; Fiori, Francesco; Foà, Lorenzo; Giassi, Alessandro; Kraan, Aafke; Ligabue, Franco; Lomtadze, Teimuraz; Martini, Luca; Messineo, Alberto; Palla, Fabrizio; Rizzi, Andrea; Serban, Alin Titus; Spagnolo, Paolo; Squillacioti, Paola; Tenchini, Roberto; Tonelli, Guido; Venturi, Andrea; Verdini, Piero Giorgio; Barone, Luciano; Cavallari, Francesca; Del Re, Daniele; Diemoz, Marcella; Fanelli, Cristiano; Grassi, Marco; Longo, Egidio; Meridiani, Paolo; Micheli, Francesco; Nourbakhsh, Shervin; Organtini, Giovanni; Paramatti, Riccardo; Rahatlou, Shahram; Sigamani, Michael; Soffi, Livia; Amapane, Nicola; Arcidiacono, Roberta; Argiro, Stefano; Arneodo, Michele; Biino, Cristina; Cartiglia, Nicolo; Costa, Marco; Demaria, Natale; Mariotti, Chiara; Maselli, Silvia; Migliore, Ernesto; Monaco, Vincenzo; Musich, Marco; Obertino, Maria Margherita; Pastrone, Nadia; Pelliccioni, Mario; Potenza, Alberto; Romero, Alessandra; Ruspa, Marta; Sacchi, Roberto; Solano, Ada; Staiano, Amedeo; Vilela Pereira, Antonio; Belforte, Stefano; Candelise, Vieri; Casarsa, Massimo; Cossutti, Fabio; Della Ricca, Giuseppe; Gobbo, Benigno; Marone, Matteo; Montanino, Damiana; Penzo, Aldo; Schizzi, Andrea; Heo, Seong Gu; Kim, Tae Yeon; Nam, Soon-Kwon; Chang, Sunghyun; Kim, Dong Hee; Kim, Gui Nyun; Kong, Dae Jung; Park, Hyangkyu; Ro, Sang-Ryul; Son, Dong-Chul; Son, Taejin; Kim, Jae Yool; Kim, Zero Jaeho; Song, Sanghyeon; Choi, Suyong; Gyun, Dooyeon; Hong, Byung-Sik; Jo, Mihee; Kim, Hyunchul; Kim, Tae Jeong; Lee, Kyong Sei; Moon, Dong Ho; Park, Sung Keun; Choi, Minkyoo; Kim, Ji Hyun; Park, Chawon; Park, Inkyu; Park, Sangnam; Ryu, Geonmo; Cho, Yongjin; Choi, Young-Il; Choi, Young Kyu; Goh, Junghwan; Kim, Min Suk; Kwon, Eunhyang; Lee, Byounghoon; Lee, Jongseok; Lee, Sungeun; Seo, Hyunkwan; Yu, Intae; Bilinskas, Mykolas Jurgis; Grigelionis, Ignas; Janulis, Mindaugas; Juodagalvis, Andrius; Castilla-Valdez, Heriberto; De La Cruz-Burelo, Eduard; Heredia-de La Cruz, Ivan; Lopez-Fernandez, Ricardo; Magaña Villalba, Ricardo; Martínez-Ortega, Jorge; Sánchez-Hernández, Alberto; Villasenor-Cendejas, Luis Manuel; Carrillo Moreno, Salvador; Vazquez Valencia, Fabiola; Salazar Ibarguen, Humberto Antonio; Casimiro Linares, Edgar; Morelos Pineda, Antonio; Reyes-Santos, Marco A; Krofcheck, David; Bell, Alan James; Butler, Philip H; Doesburg, Robert; Reucroft, Steve; Silverwood, Hamish; Ahmad, Muhammad; Ansari, Muhammad Hamid; Asghar, Muhammad Irfan; Hoorani, Hafeez R; Khalid, Shoaib; Khan, Wajid Ali; Khurshid, Taimoor; Qazi, Shamona; Shah, Mehar Ali; Shoaib, Muhammad; Bialkowska, Helena; Boimska, Bożena; Frueboes, Tomasz; Gokieli, Ryszard; Górski, Maciej; Kazana, Malgorzata; Nawrocki, Krzysztof; Romanowska-Rybinska, Katarzyna; Szleper, Michal; Wrochna, Grzegorz; Zalewski, Piotr; Brona, Grzegorz; Bunkowski, Karol; Cwiok, Mikolaj; Dominik, Wojciech; Doroba, Krzysztof; Kalinowski, Artur; Konecki, Marcin; Krolikowski, Jan; Almeida, Nuno; Bargassa, Pedrame; David Tinoco Mendes, Andre; Faccioli, Pietro; Ferreira Parracho, Pedro Guilherme; Gallinaro, Michele; Seixas, Joao; Varela, Joao; Vischia, Pietro; Bunin, Pavel; Gavrilenko, Mikhail; Golutvin, Igor; Gorbunov, Ilya; Karjavin, Vladimir; Konoplyanikov, Viktor; Kozlov, Guennady; Lanev, Alexander; Malakhov, Alexander; Moisenz, Petr; Palichik, Vladimir; Perelygin, Victor; Savina, Maria; Shmatov, Sergey; Smirnov, Vitaly; Volodko, Anton; Zarubin, Anatoli; Evstyukhin, Sergey; Golovtsov, Victor; Ivanov, Yury; Kim, Victor; Levchenko, Petr; Murzin, Victor; Oreshkin, Vadim; Smirnov, Igor; Sulimov, Valentin; Uvarov, Lev; Vavilov, Sergey; Vorobyev, Alexey; Vorobyev, Andrey; Andreev, Yuri; Dermenev, Alexander; Gninenko, Sergei; Golubev, Nikolai; Kirsanov, Mikhail; Krasnikov, Nikolai; Matveev, Viktor; Pashenkov, Anatoli; Tlisov, Danila; Toropin, Alexander; Epshteyn, Vladimir; Erofeeva, Maria; Gavrilov, Vladimir; Kossov, Mikhail; Lychkovskaya, Natalia; Popov, Vladimir; Safronov, Grigory; Semenov, Sergey; Stolin, Viatcheslav; Vlasov, Evgueni; Zhokin, Alexander; Belyaev, Andrey; Boos, Edouard; Dubinin, Mikhail; Dudko, Lev; Ershov, Alexander; Gribushin, Andrey; Klyukhin, Vyacheslav; Kodolova, Olga; Lokhtin, Igor; Markina, Anastasia; Obraztsov, Stepan; Perfilov, Maxim; Petrushanko, Sergey; Popov, Andrey; Sarycheva, Ludmila; Savrin, Viktor; Snigirev, Alexander; Andreev, Vladimir; Azarkin, Maksim; Dremin, Igor; Kirakosyan, Martin; Leonidov, Andrey; Mesyats, Gennady; Rusakov, Sergey V; Vinogradov, Alexey; Azhgirey, Igor; Bayshev, Igor; Bitioukov, Sergei; Grishin, Viatcheslav; Kachanov, Vassili; Konstantinov, Dmitri; Krychkine, Victor; Petrov, Vladimir; Ryutin, Roman; Sobol, Andrei; Tourtchanovitch, Leonid; Troshin, Sergey; Tyurin, Nikolay; Uzunian, Andrey; Volkov, Alexey; Adzic, Petar; Djordjevic, Milos; Ekmedzic, Marko; Krpic, Dragomir; Milosevic, Jovan; Aguilar-Benitez, Manuel; Alcaraz Maestre, Juan; Arce, Pedro; Battilana, Carlo; Calvo, Enrique; Cerrada, Marcos; Chamizo Llatas, Maria; Colino, Nicanor; De La Cruz, Begona; Delgado Peris, Antonio; Domínguez Vázquez, Daniel; Fernandez Bedoya, Cristina; Fernández Ramos, Juan Pablo; Ferrando, Antonio; Flix, Jose; Fouz, Maria Cruz; Garcia-Abia, Pablo; Gonzalez Lopez, Oscar; Goy Lopez, Silvia; Hernandez, Jose M; Josa, Maria Isabel; Merino, Gonzalo; Puerta Pelayo, Jesus; Quintario Olmeda, Adrián; Redondo, Ignacio; Romero, Luciano; Santaolalla, Javier; Soares, Mara Senghi; Willmott, Carlos; Albajar, Carmen; Codispoti, Giuseppe; de Trocóniz, Jorge F; Brun, Hugues; Cuevas, Javier; Fernandez Menendez, Javier; Folgueras, Santiago; Gonzalez Caballero, Isidro; Lloret Iglesias, Lara; Piedra Gomez, Jonatan; Brochero Cifuentes, Javier Andres; Cabrillo, Iban Jose; Calderon, Alicia; Chuang, Shan-Huei; Duarte Campderros, Jordi; Felcini, Marta; Fernandez, Marcos; Gomez, Gervasio; Gonzalez Sanchez, Javier; Graziano, Alberto; Jorda, Clara; Lopez Virto, Amparo; Marco, Jesus; Marco, Rafael; Martinez Rivero, Celso; Matorras, Francisco; Munoz Sanchez, Francisca Javiela; Rodrigo, Teresa; Rodríguez-Marrero, Ana Yaiza; Ruiz-Jimeno, Alberto; Scodellaro, Luca; Vila, Ivan; Vilar Cortabitarte, Rocio; Abbaneo, Duccio; Auffray, Etiennette; Auzinger, Georg; Bachtis, Michail; Baillon, Paul; Ball, Austin; Barney, David; Benitez, Jose F; Bernet, Colin; Bianchi, Giovanni; Bloch, Philippe; Bocci, Andrea; Bonato, Alessio; Botta, Cristina; Breuker, Horst; Camporesi, Tiziano; Cerminara, Gianluca; Christiansen, Tim; Coarasa Perez, Jose Antonio; D'Enterria, David; Dabrowski, Anne; De Roeck, Albert; Di Guida, Salvatore; Dobson, Marc; Dupont-Sagorin, Niels; Elliott-Peisert, Anna; Frisch, Benjamin; Funk, Wolfgang; Georgiou, Georgios; Giffels, Manuel; Gigi, Dominique; Gill, Karl; Giordano, Domenico; Girone, Maria; Giunta, Marina; Glege, Frank; Gomez-Reino Garrido, Robert; Govoni, Pietro; Gowdy, Stephen; Guida, Roberto; Hansen, Magnus; Harris, Philip; Hartl, Christian; Harvey, John; Hegner, Benedikt; Hinzmann, Andreas; Innocente, Vincenzo; Janot, Patrick; Kaadze, Ketino; Karavakis, Edward; Kousouris, Konstantinos; Lecoq, Paul; Lee, Yen-Jie; Lenzi, Piergiulio; Lourenco, Carlos; Magini, Nicolo; Maki, Tuula; Malberti, Martina; Malgeri, Luca; Mannelli, Marcello; Masetti, Lorenzo; Meijers, Frans; Mersi, Stefano; Meschi, Emilio; Moser, Roland; Mozer, Matthias Ulrich; Mulders, Martijn; Musella, Pasquale; Nesvold, Erik; Orimoto, Toyoko; Orsini, Luciano; Palencia Cortezon, Enrique; Perez, Emmanuelle; Perrozzi, Luca; Petrilli, Achille; Pfeiffer, Andreas; Pierini, Maurizio; Pimiä, Martti; Piparo, Danilo; Polese, Giovanni; Quertenmont, Loic; Racz, Attila; Reece, William; Rodrigues Antunes, Joao; Rolandi, Gigi; Rovelli, Chiara; Rovere, Marco; Sakulin, Hannes; Santanastasio, Francesco; Schäfer, Christoph; Schwick, Christoph; Segoni, Ilaria; Sekmen, Sezen; Sharma, Archana; Siegrist, Patrice; Silva, Pedro; Simon, Michal; Sphicas, Paraskevas; Spiga, Daniele; Tsirou, Andromachi; Veres, Gabor Istvan; Vlimant, Jean-Roch; Wöhri, Hermine Katharina; Worm, Steven; Zeuner, Wolfram Dietrich; Bertl, Willi; Deiters, Konrad; Erdmann, Wolfram; Gabathuler, Kurt; Horisberger, Roland; Ingram, Quentin; Kaestli, Hans-Christian; König, Stefan; Kotlinski, Danek; Langenegger, Urs; Meier, Frank; Renker, Dieter; Rohe, Tilman; Sibille, Jennifer; Bäni, Lukas; Bortignon, Pierluigi; Buchmann, Marco-Andrea; Casal, Bruno; Chanon, Nicolas; Deisher, Amanda; Dissertori, Günther; Dittmar, Michael; Donegà, Mauro; Dünser, Marc; Eugster, Jürg; Freudenreich, Klaus; Grab, Christoph; Hits, Dmitry; Lecomte, Pierre; Lustermann, Werner; Marini, Andrea Carlo; Martinez Ruiz del Arbol, Pablo; Mohr, Niklas; Moortgat, Filip; Nägeli, Christoph; Nef, Pascal; Nessi-Tedaldi, Francesca; Pandolfi, Francesco; Pape, Luc; Pauss, Felicitas; Peruzzi, Marco; Ronga, Frederic Jean; Rossini, Marco; Sala, Leonardo; Sanchez, Ann - Karin; Starodumov, Andrei; Stieger, Benjamin; Takahashi, Maiko; Tauscher, Ludwig; Thea, Alessandro; Theofilatos, Konstantinos; Treille, Daniel; Urscheler, Christina; Wallny, Rainer; Weber, Hannsjoerg Artur; Wehrli, Lukas; Amsler, Claude; Chiochia, Vincenzo; De Visscher, Simon; Favaro, Carlotta; Ivova Rikova, Mirena; Millan Mejias, Barbara; Otiougova, Polina; Robmann, Peter; Snoek, Hella; Tupputi, Salvatore; Verzetti, Mauro; Chang, Yuan-Hann; Chen, Kuan-Hsin; Kuo, Chia-Ming; Li, Syue-Wei; Lin, Willis; Liu, Zong-Kai; Lu, Yun-Ju; Mekterovic, Darko; Singh, Anil; Volpe, Roberta; Yu, Shin-Shan; Bartalini, Paolo; Chang, Paoti; Chang, You-Hao; Chang, Yu-Wei; Chao, Yuan; Chen, Kai-Feng; Dietz, Charles; Grundler, Ulysses; Hou, George Wei-Shu; Hsiung, Yee; Kao, Kai-Yi; Lei, Yeong-Jyi; Lu, Rong-Shyang; Majumder, Devdatta; Petrakou, Eleni; Shi, Xin; Shiu, Jing-Ge; Tzeng, Yeng-Ming; Wan, Xia; Wang, Minzu; Asavapibhop, Burin; Srimanobhas, Norraphat; Adiguzel, Aytul; Bakirci, Mustafa Numan; Cerci, Salim; Dozen, Candan; Dumanoglu, Isa; Eskut, Eda; Girgis, Semiray; Gokbulut, Gul; Gurpinar, Emine; Hos, Ilknur; Kangal, Evrim Ersin; Karaman, Turker; Karapinar, Guler; Kayis Topaksu, Aysel; Onengut, Gulsen; Ozdemir, Kadri; Ozturk, Sertac; Polatoz, Ayse; Sogut, Kenan; Sunar Cerci, Deniz; Tali, Bayram; Topakli, Huseyin; Vergili, Latife Nukhet; Vergili, Mehmet; Akin, Ilina Vasileva; Aliev, Takhmasib; Bilin, Bugra; Bilmis, Selcuk; Deniz, Muhammed; Gamsizkan, Halil; Guler, Ali Murat; Ocalan, Kadir; Ozpineci, Altug; Serin, Meltem; Sever, Ramazan; Surat, Ugur Emrah; Yalvac, Metin; Yildirim, Eda; Zeyrek, Mehmet; Gülmez, Erhan; Isildak, Bora; Kaya, Mithat; Kaya, Ozlem; Ozkorucuklu, Suat; Sonmez, Nasuf; Cankocak, Kerem; Levchuk, Leonid; Bostock, Francis; Brooke, James John; Clement, Emyr; Cussans, David; Flacher, Henning; Frazier, Robert; Goldstein, Joel; Grimes, Mark; Heath, Greg P; Heath, Helen F; Kreczko, Lukasz; Metson, Simon; Newbold, Dave M; Nirunpong, Kachanon; Poll, Anthony; Senkin, Sergey; Smith, Vincent J; Williams, Thomas; Basso, Lorenzo; Bell, Ken W; Belyaev, Alexander; Brew, Christopher; Brown, Robert M; Cockerill, David JA; Coughlan, John A; Harder, Kristian; Harper, Sam; Jackson, James; Kennedy, Bruce W; Olaiya, Emmanuel; Petyt, David; Radburn-Smith, Benjamin Charles; Shepherd-Themistocleous, Claire; Tomalin, Ian R; Womersley, William John; Bainbridge, Robert; Ball, Gordon; Beuselinck, Raymond; Buchmuller, Oliver; Colling, David; Cripps, Nicholas; Cutajar, Michael; Dauncey, Paul; Davies, Gavin; Della Negra, Michel; Ferguson, William; Fulcher, Jonathan; Futyan, David; Gilbert, Andrew; Guneratne Bryer, Arlo; Hall, Geoffrey; Hatherell, Zoe; Hays, Jonathan; Iles, Gregory; Jarvis, Martyn; Karapostoli, Georgia; Lyons, Louis; Magnan, Anne-Marie; Marrouche, Jad; Mathias, Bryn; Nandi, Robin; Nash, Jordan; Nikitenko, Alexander; Papageorgiou, Anastasios; Pela, Joao; Pesaresi, Mark; Petridis, Konstantinos; Pioppi, Michele; Raymond, David Mark; Rogerson, Samuel; Rose, Andrew; Ryan, Matthew John; Seez, Christopher; Sharp, Peter; Sparrow, Alex; Stoye, Markus; Tapper, Alexander; Vazquez Acosta, Monica; Virdee, Tejinder; Wakefield, Stuart; Wardle, Nicholas; Whyntie, Tom; Chadwick, Matthew; Cole, Joanne; Hobson, Peter R; Khan, Akram; Kyberd, Paul; Leggat, Duncan; Leslie, Dawn; Martin, William; Reid, Ivan; Symonds, Philip; Teodorescu, Liliana; Turner, Mark; Hatakeyama, Kenichi; Liu, Hongxuan; Scarborough, Tara; Charaf, Otman; Henderson, Conor; Rumerio, Paolo; Avetisyan, Aram; Bose, Tulika; Fantasia, Cory; Heister, Arno; St John, Jason; Lawson, Philip; Lazic, Dragoslav; Rohlf, James; Sperka, David; Sulak, Lawrence; Alimena, Juliette; Bhattacharya, Saptaparna; Cutts, David; Demiragli, Zeynep; Ferapontov, Alexey; Heintz, Ulrich; Jabeen, Shabnam; Kukartsev, Gennadiy; Laird, Edward; Landsberg, Greg; Luk, Michael; Narain, Meenakshi; Nguyen, Duong; Segala, Michael; Sinthuprasith, Tutanon; Speer, Thomas; Tsang, Ka Vang; Breedon, Richard; Breto, Guillermo; Calderon De La Barca Sanchez, Manuel; Chauhan, Sushil; Chertok, Maxwell; Conway, John; Conway, Rylan; Cox, Peter Timothy; Dolen, James; Erbacher, Robin; Gardner, Michael; Houtz, Rachel; Ko, Winston; Kopecky, Alexandra; Lander, Richard; Mall, Orpheus; Miceli, Tia; Pellett, Dave; Ricci-Tam, Francesca; Rutherford, Britney; Searle, Matthew; Smith, John; Squires, Michael; Tripathi, Mani; Vasquez Sierra, Ricardo; Yohay, Rachel; Andreev, Valeri; Cline, David; Cousins, Robert; Duris, Joseph; Erhan, Samim; Everaerts, Pieter; Farrell, Chris; Hauser, Jay; Ignatenko, Mikhail; Jarvis, Chad; Plager, Charles; Rakness, Gregory; Schlein, Peter; Traczyk, Piotr; Valuev, Vyacheslav; Weber, Matthias; Babb, John; Clare, Robert; Dinardo, Mauro Emanuele; Ellison, John Anthony; Gary, J William; Giordano, Ferdinando; Hanson, Gail; Jeng, Geng-Yuan; Liu, Hongliang; Long, Owen Rosser; Luthra, Arun; Nguyen, Harold; Paramesvaran, Sudarshan; Sturdy, Jared; Sumowidagdo, Suharyo; Wilken, Rachel; Wimpenny, Stephen; Andrews, Warren; Branson, James G; Cerati, Giuseppe Benedetto; Cittolin, Sergio; Evans, David; Golf, Frank; Holzner, André; Kelley, Ryan; Lebourgeois, Matthew; Letts, James; Macneill, Ian; Mangano, Boris; Padhi, Sanjay; Palmer, Christopher; Petrucciani, Giovanni; Pieri, Marco; Sani, Matteo; Sharma, Vivek; Simon, Sean; Sudano, Elizabeth; Tadel, Matevz; Tu, Yanjun; Vartak, Adish; Wasserbaech, Steven; Würthwein, Frank; Yagil, Avraham; Yoo, Jaehyeok; Barge, Derek; Bellan, Riccardo; Campagnari, Claudio; D'Alfonso, Mariarosaria; Danielson, Thomas; Flowers, Kristen; Geffert, Paul; Incandela, Joe; Justus, Christopher; Kalavase, Puneeth; Koay, Sue Ann; Kovalskyi, Dmytro; Krutelyov, Vyacheslav; Lowette, Steven; Mccoll, Nickolas; Pavlunin, Viktor; Rebassoo, Finn; Ribnik, Jacob; Richman, Jeffrey; Rossin, Roberto; Stuart, David; To, Wing; West, Christopher; Apresyan, Artur; Bornheim, Adolf; Chen, Yi; Di Marco, Emanuele; Duarte, Javier; Gataullin, Marat; Ma, Yousi; Mott, Alexander; Newman, Harvey B; Rogan, Christopher; Spiropulu, Maria; Timciuc, Vladlen; Veverka, Jan; Wilkinson, Richard; Xie, Si; Yang, Yong; Zhu, Ren-Yuan; Akgun, Bora; Azzolini, Virginia; Calamba, Aristotle; Carroll, Ryan; Ferguson, Thomas; Iiyama, Yutaro; Jang, Dong Wook; Liu, Yueh-Feng; Paulini, Manfred; Vogel, Helmut; Vorobiev, Igor; Cumalat, John Perry; Drell, Brian Robert; Ford, William T; Gaz, Alessandro; Luiggi Lopez, Eduardo; Smith, James; Stenson, Kevin; Ulmer, Keith; Wagner, Stephen Robert; Alexander, James; Chatterjee, Avishek; Eggert, Nicholas; Gibbons, Lawrence Kent; Heltsley, Brian; Khukhunaishvili, Aleko; Kreis, Benjamin; Mirman, Nathan; Nicolas Kaufman, Gala; Patterson, Juliet Ritchie; Ryd, Anders; Salvati, Emmanuele; Sun, Werner; Teo, Wee Don; Thom, Julia; Thompson, Joshua; Tucker, Jordan; Vaughan, Jennifer; Weng, Yao; Winstrom, Lucas; Wittich, Peter; Winn, Dave; Abdullin, Salavat; Albrow, Michael; Anderson, Jacob; Bauerdick, Lothar AT; Beretvas, Andrew; Berryhill, Jeffrey; Bhat, Pushpalatha C; Bloch, Ingo; Burkett, Kevin; Butler, Joel Nathan; Chetluru, Vasundhara; Cheung, Harry; Chlebana, Frank; Elvira, Victor Daniel; Fisk, Ian; Freeman, Jim; Gao, Yanyan; Green, Dan; Gutsche, Oliver; Hanlon, Jim; Harris, Robert M; Hirschauer, James; Hooberman, Benjamin; Jindariani, Sergo; Johnson, Marvin; Joshi, Umesh; Kilminster, Benjamin; Klima, Boaz; Kunori, Shuichi; Kwan, Simon; Leonidopoulos, Christos; Linacre, Jacob; Lincoln, Don; Lipton, Ron; Lykken, Joseph; Maeshima, Kaori; Marraffino, John Michael; Maruyama, Sho; Mason, David; McBride, Patricia; Mishra, Kalanand; Mrenna, Stephen; Musienko, Yuri; Newman-Holmes, Catherine; O'Dell, Vivian; Prokofyev, Oleg; Sexton-Kennedy, Elizabeth; Sharma, Seema; Spalding, William J; Spiegel, Leonard; Taylor, Lucas; Tkaczyk, Slawek; Tran, Nhan Viet; Uplegger, Lorenzo; Vaandering, Eric Wayne; Vidal, Richard; Whitmore, Juliana; Wu, Weimin; Yang, Fan; Yumiceva, Francisco; Yun, Jae Chul; Acosta, Darin; Avery, Paul; Bourilkov, Dimitri; Chen, Mingshui; Cheng, Tongguang; Das, Souvik; De Gruttola, Michele; Di Giovanni, Gian Piero; Dobur, Didar; Drozdetskiy, Alexey; Field, Richard D; Fisher, Matthew; Fu, Yu; Furic, Ivan-Kresimir; Gartner, Joseph; Hugon, Justin; Kim, Bockjoo; Konigsberg, Jacobo; Korytov, Andrey; Kropivnitskaya, Anna; Kypreos, Theodore; Low, Jia Fu; Matchev, Konstantin; Milenovic, Predrag; Mitselmakher, Guenakh; Muniz, Lana; Park, Myeonghun; Remington, Ronald; Rinkevicius, Aurelijus; Sellers, Paul; Skhirtladze, Nikoloz; Snowball, Matthew; Yelton, John; Zakaria, Mohammed; Gaultney, Vanessa; Hewamanage, Samantha; Lebolo, Luis Miguel; Linn, Stephan; Markowitz, Pete; Martinez, German; Rodriguez, Jorge Luis; Adams, Todd; Askew, Andrew; Bochenek, Joseph; Chen, Jie; Diamond, Brendan; Gleyzer, Sergei V; Haas, Jeff; Hagopian, Sharon; Hagopian, Vasken; Jenkins, Merrill; Johnson, Kurtis F; Prosper, Harrison; Veeraraghavan, Venkatesh; Weinberg, Marc; Baarmand, Marc M; Dorney, Brian; Hohlmann, Marcus; Kalakhety, Himali; Vodopiyanov, Igor; Adams, Mark Raymond; Anghel, Ioana Maria; Apanasevich, Leonard; Bai, Yuting; Bazterra, Victor Eduardo; Betts, Russell Richard; Bucinskaite, Inga; Callner, Jeremy; Cavanaugh, Richard; Evdokimov, Olga; Gauthier, Lucie; Gerber, Cecilia Elena; Hofman, David Jonathan; Khalatyan, Samvel; Lacroix, Florent; Malek, Magdalena; O'Brien, Christine; Silkworth, Christopher; Strom, Derek; Turner, Paul; Varelas, Nikos; Akgun, Ugur; Albayrak, Elif Asli; Bilki, Burak; Clarida, Warren; Duru, Firdevs; Merlo, Jean-Pierre; Mermerkaya, Hamit; Mestvirishvili, Alexi; Moeller, Anthony; Nachtman, Jane; Newsom, Charles Ray; Norbeck, Edwin; Onel, Yasar; Ozok, Ferhat; Sen, Sercan; Tan, Ping; Tiras, Emrah; Wetzel, James; Yetkin, Taylan; Yi, Kai; Barnett, Bruce Arnold; Blumenfeld, Barry; Bolognesi, Sara; Fehling, David; Giurgiu, Gavril; Gritsan, Andrei; Guo, Zijin; Hu, Guofan; Maksimovic, Petar; Rappoccio, Salvatore; Swartz, Morris; Whitbeck, Andrew; Baringer, Philip; Bean, Alice; Benelli, Gabriele; Kenny Iii, Raymond Patrick; Murray, Michael; Noonan, Daniel; Sanders, Stephen; Stringer, Robert; Tinti, Gemma; Wood, Jeffrey Scott; Zhukova, Victoria; Barfuss, Anne-Fleur; Bolton, Tim; Chakaberia, Irakli; Ivanov, Andrew; Khalil, Sadia; Makouski, Mikhail; Maravin, Yurii; Shrestha, Shruti; Svintradze, Irakli; Gronberg, Jeffrey; Lange, David; Wright, Douglas; Baden, Drew; Boutemeur, Madjid; Calvert, Brian; Eno, Sarah Catherine; Gomez, Jaime; Hadley, Nicholas John; Kellogg, Richard G; Kirn, Malina; Kolberg, Ted; Lu, Ying; Marionneau, Matthieu; Mignerey, Alice; Pedro, Kevin; Peterman, Alison; Skuja, Andris; Temple, Jeffrey; Tonjes, Marguerite; Tonwar, Suresh C; Twedt, Elizabeth; Apyan, Aram; Bauer, Gerry; Bendavid, Joshua; Busza, Wit; Butz, Erik; Cali, Ivan Amos; Chan, Matthew; Dutta, Valentina; Gomez Ceballos, Guillelmo; Goncharov, Maxim; Hahn, Kristan Allan; Kim, Yongsun; Klute, Markus; Krajczar, Krisztian; Luckey, Paul David; Ma, Teng; Nahn, Steve; Paus, Christoph; Ralph, Duncan; Roland, Christof; Roland, Gunther; Rudolph, Matthew; Stephans, George; Stöckli, Fabian; Sumorok, Konstanty; Sung, Kevin; Velicanu, Dragos; Wenger, Edward Allen; Wolf, Roger; Wyslouch, Bolek; Yang, Mingming; Yilmaz, Yetkin; Yoon, Sungho; Zanetti, Marco; Cooper, Seth; Dahmes, Bryan; De Benedetti, Abraham; Franzoni, Giovanni; Gude, Alexander; Kao, Shih-Chuan; Klapoetke, Kevin; Kubota, Yuichi; Mans, Jeremy; Pastika, Nathaniel; Rusack, Roger; Sasseville, Michael; Singovsky, Alexander; Tambe, Norbert; Turkewitz, Jared; Cremaldi, Lucien Marcus; Kroeger, Rob; Perera, Lalith; Rahmat, Rahmat; Sanders, David A; Avdeeva, Ekaterina; Bloom, Kenneth; Bose, Suvadeep; Butt, Jamila; Claes, Daniel R; Dominguez, Aaron; Eads, Michael; Keller, Jason; Kravchenko, Ilya; Lazo-Flores, Jose; Malbouisson, Helena; Malik, Sudhir; Snow, Gregory R; Godshalk, Andrew; Iashvili, Ia; Jain, Supriya; Kharchilava, Avto; Kumar, Ashish; Alverson, George; Barberis, Emanuela; Baumgartel, Darin; Chasco, Matthew; Haley, Joseph; Nash, David; Trocino, Daniele; Wood, Darien; Zhang, Jinzhong; Anastassov, Anton; Kubik, Andrew; Mucia, Nicholas; Odell, Nathaniel; Ofierzynski, Radoslaw Adrian; Pollack, Brian; Pozdnyakov, Andrey; Schmitt, Michael; Stoynev, Stoyan; Velasco, Mayda; Won, Steven; Antonelli, Louis; Berry, Douglas; Brinkerhoff, Andrew; Chan, Kwok Ming; Hildreth, Michael; Jessop, Colin; Karmgard, Daniel John; Kolb, Jeff; Lannon, Kevin; Luo, Wuming; Lynch, Sean; Marinelli, Nancy; Morse, David Michael; Pearson, Tessa; Planer, Michael; Ruchti, Randy; Slaunwhite, Jason; Valls, Nil; Wayne, Mitchell; Wolf, Matthias; Bylsma, Ben; Durkin, Lloyd Stanley; Hill, Christopher; Hughes, Richard; Kotov, Khristian; Ling, Ta-Yung; Puigh, Darren; Rodenburg, Marissa; Vuosalo, Carl; Williams, Grayson; Winer, Brian L; Adam, Nadia; Berry, Edmund; Elmer, Peter; Gerbaudo, Davide; Halyo, Valerie; Hebda, Philip; Hegeman, Jeroen; Hunt, Adam; Jindal, Pratima; Lopes Pegna, David; Lujan, Paul; Marlow, Daniel; Medvedeva, Tatiana; Mooney, Michael; Olsen, James; Piroué, Pierre; Quan, Xiaohang; Raval, Amita; Safdi, Ben; Saka, Halil; Stickland, David; Tully, Christopher; Werner, Jeremy Scott; Zuranski, Andrzej; Brownson, Eric; Lopez, Angel; Mendez, Hector; Ramirez Vargas, Juan Eduardo; Alagoz, Enver; Barnes, Virgil E; Benedetti, Daniele; Bolla, Gino; Bortoletto, Daniela; De Mattia, Marco; Everett, Adam; Hu, Zhen; Jones, Matthew; Koybasi, Ozhan; Kress, Matthew; Laasanen, Alvin T; Leonardo, Nuno; Maroussov, Vassili; Merkel, Petra; Miller, David Harry; Neumeister, Norbert; Shipsey, Ian; Silvers, David; Svyatkovskiy, Alexey; Vidal Marono, Miguel; Yoo, Hwi Dong; Zablocki, Jakub; Zheng, Yu; Guragain, Samir; Parashar, Neeti; Adair, Antony; Boulahouache, Chaouki; Ecklund, Karl Matthew; Geurts, Frank JM; Li, Wei; Padley, Brian Paul; Redjimi, Radia; Roberts, Jay; Zabel, James; Betchart, Burton; Bodek, Arie; Chung, Yeon Sei; Covarelli, Roberto; de Barbaro, Pawel; Demina, Regina; Eshaq, Yossof; Ferbel, Thomas; Garcia-Bellido, Aran; Goldenzweig, Pablo; Han, Jiyeon; Harel, Amnon; Miner, Daniel Carl; Vishnevskiy, Dmitry; Zielinski, Marek; Bhatti, Anwar; Ciesielski, Robert; Demortier, Luc; Goulianos, Konstantin; Lungu, Gheorghe; Malik, Sarah; Mesropian, Christina; Arora, Sanjay; Barker, Anthony; Chou, John Paul; Contreras-Campana, Christian; Contreras-Campana, Emmanuel; Duggan, Daniel; Ferencek, Dinko; Gershtein, Yuri; Gray, Richard; Halkiadakis, Eva; Hidas, Dean; Lath, Amitabh; Panwalkar, Shruti; Park, Michael; Patel, Rishi; Rekovic, Vladimir; Robles, Jorge; Rose, Keith; Salur, Sevil; Schnetzer, Steve; Seitz, Claudia; Somalwar, Sunil; Stone, Robert; Thomas, Scott; Cerizza, Giordano; Hollingsworth, Matthew; Spanier, Stefan; Yang, Zong-Chang; York, Andrew; Eusebi, Ricardo; Flanagan, Will; Gilmore, Jason; Kamon, Teruki; Khotilovich, Vadim; Montalvo, Roy; Osipenkov, Ilya; Pakhotin, Yuriy; Perloff, Alexx; Roe, Jeffrey; Safonov, Alexei; Sakuma, Tai; Sengupta, Sinjini; Suarez, Indara; Tatarinov, Aysen; Toback, David; Akchurin, Nural; Damgov, Jordan; Dragoiu, Cosmin; Dudero, Phillip Russell; Jeong, Chiyoung; Kovitanggoon, Kittikul; Lee, Sung Won; Libeiro, Terence; Roh, Youn; Volobouev, Igor; Appelt, Eric; Delannoy, Andrés G; Florez, Carlos; Greene, Senta; Gurrola, Alfredo; Johns, Willard; Kurt, Pelin; Maguire, Charles; Melo, Andrew; Sharma, Monika; Sheldon, Paul; Snook, Benjamin; Tuo, Shengquan; Velkovska, Julia; Arenton, Michael Wayne; Balazs, Michael; Boutle, Sarah; Cox, Bradley; Francis, Brian; Goodell, Joseph; Hirosky, Robert; Ledovskoy, Alexander; Lin, Chuanzhe; Neu, Christopher; Wood, John; Gollapinni, Sowjanya; Harr, Robert; Karchin, Paul Edmund; Kottachchi Kankanamge Don, Chamath; Lamichhane, Pramod; Sakharov, Alexandre; Anderson, Michael; Belknap, Donald; Borrello, Laura; Carlsmith, Duncan; Cepeda, Maria; Dasu, Sridhara; Friis, Evan; Gray, Lindsey; Grogg, Kira Suzanne; Grothe, Monika; Hall-Wilton, Richard; Herndon, Matthew; Hervé, Alain; Klabbers, Pamela; Klukas, Jeffrey; Lanaro, Armando; Lazaridis, Christos; Leonard, Jessica; Loveless, Richard; Mohapatra, Ajit; Ojalvo, Isabel; Palmonari, Francesco; Pierro, Giuseppe Antonio; Ross, Ian; Savin, Alexander; Smith, Wesley H; Swanson, Joshua

    2013-01-01

    A search is presented for free heavy long-lived fractionally charged particles produced in pp collisions at $\\sqrt{s}$ = 7 TeV. The data sample was recorded by the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 inverse femtobarns. Candidate fractionally charged particles are identified by selecting tracks with associated low charge measurements in the silicon tracking detector. Observations are found to be consistent with expectations for background processes. The results of the search are used to set upper limits on the cross section for pair production of fractionally charged, massive spin-1/2 particles that are neutral under SU(3)$_C$ and SU(2)$_L$. We exclude at 95% confidence level such particles with electric charge ±2e/3 with masses below 310 GeV, and those with charge ±e/3 with masses below 140 GeV.

  2. Charging of mesospheric aerosol particles: the role of photodetachment and photoionization from meteoric smoke and ice particles

    Directory of Open Access Journals (Sweden)

    M. Rapp

    2009-06-01

    Full Text Available Time constants for photodetachment, photoemission, and electron capture are considered for two classes of mesospheric aerosol particles, i.e., meteor smoke particles (MSPs and pure water ice particles. Assuming that MSPs consist of metal oxides like Fe2O3 or SiO, we find that during daytime conditions photodetachment by solar photons is up to 4 orders of magnitude faster than electron attachment such that MSPs cannot be negatively charged in the presence of sunlight. Rather, even photoemission can compete with electron capture unless the electron density becomes very large (>>1000 cm−3 such that MSPs should either be positively charged or neutral in the case of large electron densities. For pure water ice particles, however, both photodetachment and photoemission are negligible due to the wavelength characteristics of its absorption cross section and because the flux of solar photons has already dropped significantly at such short wavelengths. This means that water ice particles should normally be negatively charged. Hence, our results can readily explain the repeated observation of the coexistence of positive and negative aerosol particles in the polar summer mesopause, i.e., small MSPs should be positively charged and ice particles should be negatively charged. These results have further important implications for our understanding of the nucleation of mesospheric ice particles as well as for the interpretation of incoherent scatter radar observations of MSPs.

  3. Irradiation experiments of coated particle fuels by gas-swept capsules, (2)

    International Nuclear Information System (INIS)

    Coated fuel particles in loosely-packed condition and fuel compacts were irradiated in 75F4A and 75F5A capsules, respectively, in the 1st Be region of JMTR for four reactor periods (∼ 80 days). Each capsule consisted of three inner-capsules which were separated from each other. The samples in the 75F4A capsule were obtained from the first and second fabrication campaigns meeting the VHTR fuel specification. The fuels according to a preliminary specification had different sizes and were also charged in the 75F5A capsule. All samples in the 75F4A showed no failure during the first three reactor periods, and gave valuable data concerning fission-gas release behavior due to uranium contamination in outer pyrolytic carbon layer. The coated fuel particles in its upper inner-capsule reached 2.2 %-FIMA and experienced 1500 deg C, but R/B(88Kr) was only about 1 x 10-5; the end-of-life fraction through-coating failure (diameterEOL) was 3 x 10-4. The fuel compacts in the middle inner-capsule of 75F5A were irradiated to 1.6 %FIMA at 1600 deg C maximum, but diameterEOL was merely 5 x 10-4. Their end-of-life fraction defective SiC showed no statistically significant increase. Other data obtained were: Irradiation effects on pyrolytic carbon layers, Pd attack on SiC, fractional release of metal fission products and dimensional changes of fuel compacts. (author)

  4. The charged-particle multiplicity inside jets at 8 TeV with the ATLAS detector

    CERN Document Server

    Nachman, Benjamin Philip; The ATLAS collaboration

    2016-01-01

    The number of charged particles inside jets is a widely used discriminant for identifying the quark or gluon nature of the initiating parton and is sensitive to both the perturbative and non-perturbative components of fragmentation. This paper presents a measurement of the average number of charged particles with pT>500 MeV inside high-momentum jets in dijet events using 20.3 1/fb of data recorded with the ATLAS detector in pp collisions at s = sqrt(8) TeV collisions at the LHC. The jets considered have transverse momenta from 50 GeV up to and beyond 1.5 TeV. The reconstructed charged-particle track multiplicity distribution is unfolded to remove distortions from detector effects and the resulting charged-particle multiplicity is compared to several models. Furthermore, quark and gluon jet fractions are used to extract the average charged-particle multiplicity for quark and gluon jets separately.

  5. Threshold Laws for the Break-up of Atomic Particles into Several Charged Fragments

    OpenAIRE

    Kuchiev, M. Yu.; Ostrovsky, V. N.

    1998-01-01

    The processes with three or more charged particles in the final state exhibit particular threshold behavior, as inferred by the famous Wannier law for (2e + ion) system. We formulate a general solution which determines the threshold behavior of the cross section for multiple fragmentation. Applications to several systems of particular importance with three, four and five leptons (electrons and positrons) in the field of charged core; and two pairs of identical particles with opposite charges ...

  6. New Electrically Charged Black Hole in Higher Derivative Gravity as Particle Colliders

    OpenAIRE

    Lin, Kai; Pavan, A. B.; Flores-Hidalgo, G.; Abdalla, E.

    2016-01-01

    In this paper, new electrically charged asymptotically flat black hole solutions are numerically derived in the context of higher derivative gravity. These solutions can be interpreted as generalizations of two different classes of non-charged asymptotically flat spacetimes: Schwarzschild and non-Schwarzschild solutions. The possibility to use these black holes as particle colliders have been analysed. Our results show that the center-of-mass energy of two accelerated charged particles could ...

  7. Transverse momentum spectra for charged particles at the CERN proton-antiproton collider

    International Nuclear Information System (INIS)

    We have measured transverse momentum spectra up to 10 GeV/c for charged particles produced centrally in proton-antiproton collisions at 540 GeV in the centre of mass at the CERN collider. Our results are compared with data at ISR energies and with the predictions of a QCD model. The charged particle spectrum shows a clear dependence on charged track multiplicity. (orig.)

  8. Constraints on dark matter particles charged under a hidden gauge group from primordial black holes

    OpenAIRE

    Dai, De-Chang; Freese, Katherine; Stojkovic, Dejan

    2009-01-01

    In order to accommodate increasingly tighter observational constraints on dark matter, several models have been proposed recently in which dark matter particles are charged under some hidden gauge group. Hidden gauge charges are invisible for the standard model particles, hence such scenarios are very difficult to constrain directly. However black holes are sensitive to all gauge charges, whether they belong to the standard model or not. Here, we examine the constraints on the possible values...

  9. First direct limits on Lightly Ionizing Particles with electric charge less than $e/6$

    CERN Document Server

    Agnese, R; Balakishiyeva, D; Thakur, R Basu; Bauer, D A; Billard, J; Borgland, A; Bowles, M A; Brandt, D; Brink, P L; Bunker, R; Cabrera, B; Caldwell, D O; Cerdeno, D G; Chagani, H; Chen, Y; Cooley, J; Cornell, B; Crewdson, C H; Cushman, P; Daal, M; Di Stefano, P C F; Doughty, T; Esteban, L; Fallows, S; Figueroa-Feliciano, E; Godfrey, G L; Golwala, S R; Hall, J; Harris, H R; Hertel, S A; Hofer, T; Holmgren, D; Hsu, L; Huber, M E; Jastram, A; Kamaev, O; Kara, B; Kelsey, M H; Kennedy, A; Kiveni, M; Koch, K; Leder, A; Loer, B; Asamar, E Lopez; Mahapatra, R; Mandic, V; Martinez, C; McCarthy, K A; Mirabolfathi, N; Moffatt, R A; Moore, D C; Nelson, H; Nelson, R H; Ogburn, R W; Page, K; Page, W A; Partridge, R; Pepin, M; Phipps, A; Prasad, K; Pyle, M; Qiu, H; Rau, W; Redl, P; Reisetter, A; Ricci, Y; Rogers, H E; Saab, T; Sadoulet, B; Sander, J; Schneck, K; Schnee, R W; Scorza, S; Serfass, B; Shank, B; Speller, D; Upadhyayula, S; Villano, A N; Welliver, B; Wright, D H; Yellin, S; Yen, J J; Young, B A; Zhang, J

    2014-01-01

    While the Standard Model of particle physics does not include free particles with fractional charge, experimental searches have not ruled out their existence. We report results from the Cryogenic Dark Matter Search (CDMS II) experiment that give the first direct-detection limits for cosmogenically-produced relativistic particles with electric charge lower than $e$/6. A search for tracks in the six stacked detectors of each of two of the CDMS II towers found no candidates, thereby excluding new parameter space for particles with electric charges between $e$/6 and $e$/200.

  10. In vivo tumor radiobiology of heavy charged particles

    International Nuclear Information System (INIS)

    The response of tumor cells systems to irradiation with carbon, neon and argon beams at various positions in the plateau and extended-peak regions of the Bragg ionization curve is being evaluated from experiments conducted both in vivo and in vitro. The radiobiological end points being studied include: tumor volume response, cellular survival after tumor irradiation in situ, and cell-kinetic parameters

  11. Particle discriminator for the identification of light charged particles with CsI(Tl) scintillator + PIN photodiode detector

    International Nuclear Information System (INIS)

    A particle discriminator exploiting the ballistic deficit effect for pulse shape discrimination has been developed for CsI(Tl) scintillator + PIN photodiode charged-particle detectors. The method is theoretically investigated and it is shown that the figure of merit of the particle separation is mainly governed by the absolute value of the differential quotient of the rise time dependent ballistic deficit. As the actual particle discriminator contains shaping amplifiers, baseline restorer, pile-up rejector and analog-to-digital converters, it directly accepts signals from a charge-sensitive preamplifier, and its outputs deliver the type and the energy of the particles in the form of eight-bit digital codes. The performance of the particle discriminator is characterised by the figure-of-merit measured as a function of the particle energy. (orig.)

  12. Fluorescence time-lapse imaging of single cells targeted with a focused scanning charged-particle microbeam

    Energy Technology Data Exchange (ETDEWEB)

    Bourret, Stéphane [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Vianna, François [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); IRSN, BP 3, F-13115 Saint-Paul Lez Durance (France); Devès, Guillaume [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Atallah, Vincent [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Department of Radiation Oncology, Institut Bergonié, Bordeaux (France); Univ. Victor Segalen, Bordeaux (France); Moretto, Philippe; Seznec, Hervé [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France); Barberet, Philippe, E-mail: barberet@cenbg.in2p3.fr [Univ. Bordeaux, CENBG, UMR 5797, F-33170 Gradignan (France); CNRS, IN2P3, CENBG, UMR 5797, F-33170 Gradignan (France)

    2014-04-01

    Charged particle microbeams provide unique features to study targeted and non-targeted radiation response and have recently emerged as a powerful tool to investigate radiation-induced DNA damage and repair. We have developed a charged particle microbeam delivering protons and alpha particles in the MeV energy range equipped with online time-lapse imaging capabilities. The beam is focused to a sub-micrometer beam spot under vacuum by means of a triplet of magnetic quadrupoles and extracted in air through a 200 nm Si{sub 3}N{sub 4} window. The end-station is equipped with an automated fluorescence microscope used for single cell targeting and online time-lapse imaging. Cells are kept in their medium during the irradiation procedure and the sample temperature is regulated to 37 °C. An overall targeting accuracy of 2.0 ± 0.7 μm has been measured by tracking the re-localization of the XRCC1 protein. First measurements of this re-localization shows the ability of our system to follow online the radiation-induced re-localization of proteins in the first minutes after irradiation.

  13. Investigations into properties of charge traps created in CCDs by neutron and electron irradiation

    Indian Academy of Sciences (India)

    James E Brau; Olga Igonkina; Nikolai B Sinev; Jan Strube

    2007-12-01

    Our group has been investigating the effects related to radiation damage of CCDs since 1998. In a series of measurements in 2003 we found the puzzling effect of very slow filling of charge traps created by radiation damage of the silicon device. In 2005 we intended to study this phenomenon in detail. However, while in 2003 we could see all the traps created by neutron irradiation in 1998-1997 unchanged, such traps unexpectedly almost completely disappeared in 2005. We explain this as an effect of annealing induced by electron irradiation, as in 2003 we irradiated with electrons the same device irradiated with neutrons in 1997-1998. Results of the 2005 measurements are presented.

  14. Differential gene expression induced by high LET charged particles in normal human fibroblasts

    International Nuclear Information System (INIS)

    We investigated differential gene expression of normal human skin HSF42 fibroblasts induced by heavy ions using cDNA microarray technology. Irradiation with 3 types of heavy ions was performed at Heavy Ion Medical Accelerator in Chiba (HIMAC) facility. Out of 7458 genes, we found 61 significant genes (40 up-regulated and 21 down-regulated) that distinguished between human skin fibroblast HSF42 cells non-irradiated and irradiated with 1 Gy of neon particles and 62 significant genes (48 up-regulated and 14 down-regulated) that distinguished between HSF42 cells non-irradiated and irradiated with 1 Gy of silicon particles. Furthermore, we are going to analyze profiles of HSF42 cells exposed to carbon particles and compare those profiles between different types of beams. (author)

  15. Modifications of poly (vinilydene fluoride) under electronic excitations produced by charged particles (heavy ions and electrons)

    International Nuclear Information System (INIS)

    Some of the physico-chemical properties of organic solids like conductivity or permeation can be improved by irradiation. The aim of this work is to characterize modifications induced in poly (vinylidene fluoride) films (PVDF) by charged particles (ions and electrons), with electronic stopping power, for doses ranging from zero to twenty G-Grays. Influence of dose, density of electronic excitations, and flux (in particles per square centimeter), and the nature of defects induced by the beam, were studied with two methods: X-ray Photoelectron Spectroscopy (or XPS) for surface analysis, and electron Spin Resonance (or ESR) to probe the bulk of the film. Three ranges of doses are revealed in view of experimental results. At lower doses, PVDF undergoes deshydrofluorination induced by desorption; it is a low modifications regime. For intermediate range doses, conjugated carbon backbones of polyene compounds are produced. At higher doses, intermolecular interactions between the resulting fragments give a crosslinked network. For the upper limit of doses used, bond breaking results in a non reversible degradation of PVDF. In this last situation, direct atomic displacement of target atoms, is not negligible

  16. Response of radiochromic dye films to low energy heavy charged particles

    CERN Document Server

    Buenfil, A E; Gamboa-Debuen, I; Aviles, P; Avila, O; Olvera, C; Robledo, R; Rodriguez-Ponce, M; Mercado-Uribe, H; Rodriguez-Villafuerte, M; Brandan, M E

    2002-01-01

    We have studied the possible use of radiochromic dye films (RCF) as heavy charged particle dosemeters. We present the results of irradiating two commercial RCF (GafChromic HD-810 and MD-55-1) with 1.5, 2.9 and 4.4 MeV protons, 1.4, 2.8, 4.7, 5.9, 6.8 MeV sup 4 He ions and 8.5 and 12.4 MeV sup 1 sup 2 C ions, at proton doses from about 1 Gy up to 3 kGy, helium ions doses from 3 Gy to 5 kGy and carbon ion doses from 30 Gy to 20 kGy. The films were scanned and digitized using commercial equipment. For a given particle, the response per unit dose at different energies indicates an energy dependence of the sensitivity, which is discussed. Comparison was made for the use of a standard spectrophotometer to obtain optical density readings versus a white light scanner.

  17. Influence of Magnolol on the bystander effect induced by alpha-particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wong, T.P.W.; Law, Y.L. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong); Tse, A.K.W.; Fong, W.F. [Research and Development Division, School of Chinese Medicine, Hong Kong Baptist University, Baptist University Road, Kowloon Tong (Hong Kong); Yu, K.N. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong (Hong Kong)], E-mail: peter.yu@cityu.edu.hk

    2010-04-15

    In this work, the influence of Magnolol on the bystander effect in alpha-particle irradiated Chinese hamster ovary (CHO) cells was examined. The bystander effect was studied through medium transfer experiments. Cytokinesis-block micronucleus (CBMN) assay was performed to quantify the chromosome damage induced by alpha-particle irradiation. Our results showed that the alpha-particle induced micronuclei (MN) frequencies were suppressed with the presence of Magnolol.

  18. Light charged particle emission in heavy-ion reactions – What have we learnt?

    Indian Academy of Sciences (India)

    S Kailas

    2001-07-01

    Light charged particles emitted in heavy-ion induced reactions, their spectra and angular distributions measured over a range of energies, carry the signature of the underlying reaction mechanisms. Analysis of data of light charged particles, both inclusive and exclusive measured in coincidence with gamma rays, fission products, evaporation residues have yielded interesting results which bring out the influence of nuclear structure, nuclear mean field and dynamics on the emission of these particles.

  19. Modelling the Role of Charge in Atmospheric Particle Formation Using Quantum Chemical Methods

    OpenAIRE

    Ruusuvuori, Kai

    2015-01-01

    New particle formation is an important process in the atmosphere. As ions are constantly produced in the atmosphere, the behaviour and role of charged particles in atmospheric processes needs to be understood. In order to gain insight on the role of charge in atmospheric new particle formation, the electron structure of the molecules taking part in this process needs to be taken into account using quantum chemical methods. Quantum chemical density functional theory was employed in an eff...

  20. High Energy Ionic Charge State Composition In Recent Large Solar Energetic Particle Events

    OpenAIRE

    Labrador, A. W.; Leske, R. A.; Mewaldt, R. A.; Stone, E. C.; von Rosenvinge, T. T.

    2003-01-01

    The ionic charge states of solar energetic particles (SEPs) provide information on the temperature of source materials and on conditions during acceleration and transport. SAMPEX/MAST measures mean ionic charge states at > 15 MeV/nuc using the geomagnetic rigidity filter technique. Charge state measurements by MAST for gradual SEP events suggest a continuum of charge states correlated with abundance ratios for a variety of elements, similar to what is observed at lower energies. In case...

  1. The electric charge of the aerosols under gamma radiation; La charge electrique des aerosols sous irradiation gamma

    Energy Technology Data Exchange (ETDEWEB)

    Gensdarmes, F.; Cetier, P.; Boulaud, D. [CEA/Saclay, Inst. de Protection et de Surete Nucleaire, IPSN/DPEA/SERAC, 91 - Gif-sur-Yvette (France); Renoux, A. [Paris-12 Univ., Lab. de Physique des Aerosols et de Transfert des Contaminations, 94 - Creteil (France)

    2000-07-01

    During a PWR type reactor accident, the gamma radiation may create a high ionized atmosphere. In such a situation the aerosols properties knowledge is useful to simulate the particles transport and deposit in the enclosed. The aim of this study is to determine the aerosol charges distribution in a high ionized medium, in function of the ionic properties of the medium. (A.L.B.)

  2. Investigation of surfactant mediated acid-base charging of mineral oxide particles dispersed in apolar systems.

    Science.gov (United States)

    Gacek, Matthew M; Berg, John C

    2012-12-21

    The current work examines the role of acid-base properties on particle charging in apolar media. Manipulating the polarity and magnitude of charge in such systems is of growing interest to a number of applications. A major hurdle to the implementation of this technology is that the mechanism(s) of particle charging remain a subject of debate. The authors previously conducted a study of the charging of a series of mineral oxide particles dispersed in apolar systems that contained the surfactant AOT. It was observed that there was a correlation between the particle electrophoretic mobility and the acid-base nature of the particle, as characterized by aqueous point of zero charge (PZC) or the isoelectric point (IEP). The current study investigates whether or not a similar correlation is observed with other surfactants, namely, the acidic Span 80 and the basic OLOA 11000. This is accomplished by measuring the electrophoretic mobility of a series of mineral oxides that are dispersed in Isopar-L containing various concentrations of either Span 80 or OLOA 11000. The mineral oxides used have PZC values that cover a wide range of pH, providing a systematic study of how particle and surfactant acid-base properties impact particle charge. It was found that the magnitude and polarity of particle surface charge varied linearly with the particle PZC for both surfactants used. In addition, the point at which the polarity of charge reversed for the basic surfactant OLOA 11000 was shifted to a pH of approximately 8.5, compared to the previous result of about 5 for AOT. This proves that both surfactant and particle acid-base properties are important, and provides support for the theory of acid-base charging in apolar media. PMID:23157688

  3. Ion-UHMA: a model for simulating the dynamics of neutral and charged aerosol particles.

    Energy Technology Data Exchange (ETDEWEB)

    Leppae, J.; Kerminen, V.-M. (Finnish Meteorological Institute, Climate Change Research, Helsinki (Finland)); Gagne, S.; Manninen, H. E.; Nieminen, T.; Kulmala, M. (Dept. of Physics, Univ. of Helsinki (Finland)); Laakso, L. (Dept. of Physics, Univ. of Helsinki (Finland); School of Physical and Chemical Sciences, North-West Univ. Potchefstroom (South Africa)); Korhonen, H. (Univ. of Kuopio, Dept. of Physics (Finland)); Lehtinen, K. E. J. (Univ. of Kuopio, Dept. of Physics (Finland); Finnish Meteorological Institute, Kuopio Unit (Finland))

    2009-07-01

    A new aerosol dynamical box model, Ion-UHMA (University of Helsinki Multicomponent Aerosol model for neutral and charged particles), is introduced in this paper. The model includes basic dynamical processes (condensation, coagulation and deposition) as well as ion-aerosol attachment and ion-ion recombination. The formation of particles is treated as model input or, alternatively, the model can be coupled with an existing nucleation model. Ion-UHMA was found to be able to reproduce qualitatively the measured time evolution of the particle number size distribution, when the particle formation and growth rates as well as concentrations of particles > 20 nm in diameter were taken from measurements. The simulated charging state of freshly formed particles during a new particle formation event evolved towards charge equilibrium in line with previously-derived analytical formulae. We provided a few illustrative examples to demonstrate possible applications, to which the Ion-UHMA model could be used in the near future. (orig.)

  4. Stability of precipitates in ZIRLO under high energy particle irradiation

    International Nuclear Information System (INIS)

    To investigate the stability of precipitates in ZIRLO under irradiation, specimens were irradiated by Ni+ ions and electrons at 573 K. Precipitates were analyzed by transmission electron microscope (TEM) and energy dispersive spectroscopy (EDS). Non-irradiated ZIRLO included two types of precipitates: BCC Zr–Nb and HCP Zr–Nb–Fe. After ion irradiation, the Zr–Nb-type precipitate remained BCC, while the Zr–Nb–Fe-type became amorphous without Fe depletion. This was likely due to the higher dose rate of ion irradiation compared to that of neutron irradiation, resulting in a reduced defect for the amorphous transition to occur. No precipitate change was observed after electron irradiation to 5 dpa. Results suggest that the stability of the precipitate depends on the type of damage, i.e. electrons vs. ions with presence or absence of cascades

  5. A search for relativistic particles with fractional electric charge at the Cern collider

    DEFF Research Database (Denmark)

    Banner, M.; Kofoed-Hansen, O.

    1983-01-01

    A search for relativistic particles with fractional electric charge has been performed at the CERN collider using a telescope of scintillation counters to detect particles with abnormally low ionisation. The thickness of the detector (40 gr cm−2) limits this search to particles without strong...... absorption in matter. No evidence for such particles has been found. This negative result is used to set an upper limit for the ratio of quark yield to that of particles with unit electric charge. For quark masses below 2 GeV/c2 the 90% confidence level upper limits range from 2 × 10−4 to 2.5 × 10...

  6. Irradiation performance and integrity of thorium oxide based coated particle fuels at high burnups

    International Nuclear Information System (INIS)

    In order to utilize thorium in a high temperature gas-cooled reactor (HTGR), a series of the irradiation experiments of thorium oxide based coated particle fuels have been conducted. This experiment is concerned with irradiation of the bonded TRISO- and BISO- coated (Th, U)O2 particles as fissile fuel in several variations of the Th/U ratios, U-235 enrichments, etc., and the bonded BISO- coated ThO2 particles as fertile fuel to investigate their integrity and irradiation behavior with three capsules in JMTR. Irradiation of these coated particles was achieved to a maximum neutron fluence of 2.22x1021n/cm2 (E>0.18MeV) at temperature of 1390degC, where the maximum burnup of the fissile particles was 7.3% FIMA. Both the fissile and fertile particles was 7.3% FIMA. Both the fissile and fertile particles were intact and performed well without coating failure, amoeba effect, and corrosion of the SiC layer by a fission product palladium. The data were also taken on irradiation-induced dimensional changes of the fuel compacts, failure fractions of the coated particles in these compacts measured by a newly developed acid leaching method, and on behavior of the irradiated coated fuel particles at extremely high temperatures (up to 2300degC) by an out-of-pile heating. Besides, the typical aspects of the amoeba effect were discussed on the coated particles which were irradiated in loosely-packed condition to compare irradiation performance with that for the bonded particles. (author)

  7. Electrophoretic mobility of a charged colloidal particle: a computer simulation study

    International Nuclear Information System (INIS)

    We study the mobility of a charged colloidal particle in a constant homogeneous electric field by means of computer simulations. The simulation method combines a lattice Boltzmann scheme for the fluid with standard Langevin dynamics for the colloidal particle, which is built up from a net of bonded particles forming the surface of the colloid. The coupling between the two subsystems is introduced via friction forces. In addition, explicit counterions, also coupled to the fluid, are present. We observe a non-monotonic dependence of the electrophoretic mobility on the bare colloidal charge. At low surface charge density we observe a linear increase of the mobility with bare charge, whereas at higher charges, where more than half of the ions are co-moving with the colloid, the mobility decreases with increasing bare charge

  8. Ultracold Fermi and Bose gases and Spinless Bose Charged Sound Particles

    Directory of Open Access Journals (Sweden)

    Minasyan V.

    2011-10-01

    Full Text Available We propose a novel approach for investigation of the motion of Bose or Fermi liquid (or gas which consists of decoupled electrons and ions in the uppermost hyperfine state. Hence, we use such a concept as the fluctuation motion of “charged fluid particles” or “charged fluid points” representing a charged longitudinal elastic wave. In turn, this elastic wave is quantized by spinless longitudinal Bose charged sound particles with the rest mass m and charge e 0 . The existence of spinless Bose charged sound particles allows us to present a new model for description of Bose or Fermi liquid via a non-ideal Bose gas of charged sound particles . In this respect, we introduce a new postulation for the superfluid component of Bose or Fermi liquid determined by means of charged sound particles in the condensate, which may explain the results of experiments connected with ultra-cold Fermi gases of spin-polarized hydrogen, 6 Li and 40 K, and such a Bose gas as 87 Rb in the uppermost hyperfine state, where the Bose- Einstein condensation of charged sound particles is realized by tuning the magnetic field.

  9. Trajectory of Charged Particle in Combined Electric and Magnetic Fields Using Interactive Spreadsheets

    Science.gov (United States)

    Tambade, Popat S.

    2011-01-01

    The objective of this article is to graphically illustrate to the students the physical phenomenon of motion of charged particle under the action of simultaneous electric and magnetic fields by simulating particle motion on a computer. Differential equations of motions are solved analytically and path of particle in three-dimensional space are…

  10. High-energy charged particle bursts in the near-Earth space as earthquake precursors

    Directory of Open Access Journals (Sweden)

    S. Yu. Aleksandrin

    Full Text Available The experimental data on high-energy charged particle fluxes, obtained in various near-Earth space experiments (MIR orbital station, METEOR-3, GAMMA and SAMPEX satellites were processed and analyzed with the goal to search for particle bursts. Particle bursts have been selected in every experiment considered. It was shown that the significant part of high-energy charged particle bursts correlates with seismic activity. Moreover, the particle bursts are observed several hours before strong earthquakes; L-shells of particle bursts and corresponding earthquakes are practically the same. Some features of a seismo-magnetosphere connection model, based on the interaction of electromagnetic emission of seismic origin and radiation belt particles, were considered.

    Key words. Ionospheric physics (energetic particles, trapped; energetic particles, precipitating; magnetosphere-ionosphere interactions

  11. Charge transport in irradiated graphene and Josephson structures

    International Nuclear Information System (INIS)

    In the concluding Part of this Thesis, we studied the density of states and the dc Josephson current in a multiterminal structure of cross-type geometry, which consists of four superconducting electrodes connected by one-dimensional normal metal or ferromagnetic wires, respectively. The length of the wires was assumed to be short, i.e., the Thouless energy. We considered temperatures T far below the critical temperature Tc of the superconducting electrodes, i.e., the superconducting gap parameter Δ was regarded as the T=0 value of the temperature-dependent function Δ(T). By means of the quasiclassical Green@'s function method and, in particular, the Usadel equation for diffusive superconductors, we found exact solutions for the quasiclassical Green@'s function g in the product space of particle-hole and spin variables. With the help of the matrix function g, we calculated the density of states at the crossing point and found the dependence of the Josephson current as well as of the critical Josephson current in the vertical junction on the phase difference in the horizontal junction. Referring to ferromagnetic wires connecting the superconductors, we assumed that the magnetization M in the wires is oriented along the corresponding wire and that the Thouless energy is much larger than the exchange energy. By means of the exact result for the quasiclassical Green@fs function, we showed that not only the singlet component arises in the ferromagnetic cross, but also the oddfrequency s-wave triplet component with nonzero projection of the total spin S of Cooper pairs on the M vectors is induced in the ferromagnetic wires. However, although there arises a triplet component in the system, by calculating the resulting triplet current component, we demonstrated that the Josephson current through the interfaces only consists of a singlet component, i.e., the triplet current component is exactly equal to zero.

  12. The search for elementary particles with fractional electric charge and the philosophy of speculative experiments

    International Nuclear Information System (INIS)

    All known elementary particles that can be isolated as individual particles have an electric charge that is equal in magnitude to the electron close-quote s charge, q=1.6x10-19C, or is zero. This includes the muon and tau charged leptons, the neutrinos, the photon, the nucleons, and the mesons. There have been many searches without confirmed success for isolated particles with fractional electric charge such as ±q/3, or ±q/2, or ±3q/2. The theory of the physics of elementary particles does not require the existence of such particles. In particular, current theory holds that quarks, whose charge is ±(1/3)q or ±2/3q, cannot be isolated. Despite past failures and current theory, we have been engaged for the past few years in a new search for isolated elementary particles with fractional electric charge. In the course of this paper we discuss models for fractional charge particles, summarize previous searches, and describe our experimental method; and because this is speculative research we will also present our thoughts on speculative experiments. copyright 1997 American Association of Physics Teachers

  13. Degradation of charge sharing after neutron irradiation in strip silicon detectors with different geometries

    CERN Document Server

    Casse, G

    2013-01-01

    The aim of the CERN/RD50 collaboration is the improvement of the radiation tolerance of semiconductor detectors for future experiments at high-luminosity colliders. In the RD50 framework, evidence of enhanced signal charge in severely irradiated silicon detectors (diodes, segmented planar and 3D devices) was found. The underlying mechanism was labelled charge multiplication. This has been one of the most exciting results from the research activity of RD50 because it could allow for a greatly extended radiation tolerance, if the mechanism is to be found controllable and tuneable. The charge multiplication mechanism is governed by impact ionisation from electrons drifting in high electric field. The electric field profile is influenced by the geometry of the implanted electrodes. In order to investigate the influence of the diode implantation geometry on charge multiplication, the RD50 collaboration has commissioned the production of miniature microstrip silicon sensors with various choices of strip pitch and s...

  14. Positron annihilation in electron irradiated GaAs: atomic structure and charge state of the defects

    International Nuclear Information System (INIS)

    Positron lifetime measurements show that electron irradiation produces negative vacancies and negative ions at 20 K in semi-insulating GaAs. The vacancies anneal between 77-500 K with a sharp stage in the range 270-370 K. The ions anneal at high temperature above 450 K. The negative ions are identified to isolated gallium antisites. The negative vacancies are identified to gallium vacancies either isolated or involved in negatively-charged complexes. The introduction rate of the gallium antisites is estimated to be 1.8±0.4 cm-1 after 1.5 MeV electron irradiation at 20 K

  15. Charge collection efficiency of irradiated silicon detectors operated at cryogenic temperatures

    CERN Document Server

    Borer, K; Palmieri, V G; Dezillie, B; Li, Z; Collins, P; Niinikoski, T O; Lourenço, C; Sonderegger, P; Borchi, E; Bruzzi, Mara; Pirollo, S; Granata, V; Pagano, S; Chapuy, S; Dimcovski, Zlatomir; Grigoriev, E; Bell, W; Devine, S R H; O'Shea, V; Smith, K; Berglund, P; de Boer, Wim; Hauler, F; Heising, S; Jungermann, L; Casagrande, L; Cindro, V; Mikuz, M; Zavrtanik, M; Da Vià, C; Esposito, A P; Konorov, I; Paul, S; Schmitt, L; Buontempo, S; D'Ambrosio, N; Ruggiero, G; Eremin, V V; Verbitskaya, E

    2000-01-01

    The charge collection efficiency (CCE) of heavily irradiated silicon diode detectors was investigated at temperatures between 77 and 200 K. The CCE was found to depend on the radiation dose, bias voltage value and history, temperature, and bias current generated by light. The detector irradiated to the highest fluence 2·1015 n/cm2 yields a MIP signal of at least 15000 e- both at 250 V forward bias voltage, and at 250 V reverse bias voltage in the presence of a light-generated current. The "Lazarus effect" was thus shown to extend to fluences at least ten times higher than was previously studied.

  16. Magnetic properties changes of MnAs thin films irradiated with highly charged ions

    OpenAIRE

    Trassinelli, Martino; Gafton, V.; Eddrief, Mahmoud; Eddrief, M.; Etgens, Victor H.; Etgens, V. H.; Hidki, S.; Lacaze, Emmanuelle; Lamour, Emily; Luo, X.; Marangolo, M.; Marangolo, Massimiliano; Merot, Jacques; Prigent, Christophe; Reuschl, Regina

    2013-01-01

    We present the first investigation on the effect of highly charged ion bombardment on a manganese arsenide thin film. The MnAs films, 150~nm thick, are irradiated with 90 keV Ne$^{9+}$ ions with a dose varying from $1.6\\times10^{12}$ to $1.6\\times10^{15}$~ions/cm$^2$. The structural and magnetic properties of the film after irradiation are investigated using different techniques, namely, X-ray diffraction, magneto-optic Kerr effect and magnetic force microscope. Preliminary results are presen...

  17. Heavy charged particle radiobiology: using enhanced biological effectiveness and improved beam focusing to advance cancer therapy.

    Science.gov (United States)

    Allen, Christopher; Borak, Thomas B; Tsujii, Hirohiko; Nickoloff, Jac A

    2011-06-01

    Ionizing radiation causes many types of DNA damage, including base damage and single- and double-strand breaks. Photons, including X-rays and γ-rays, are the most widely used type of ionizing radiation in radiobiology experiments, and in radiation cancer therapy. Charged particles, including protons and carbon ions, are seeing increased use as an alternative therapeutic modality. Although the facilities needed to produce high energy charged particle beams are more costly than photon facilities, particle therapy has shown improved cancer survival rates, reflecting more highly focused dose distributions and more severe DNA damage to tumor cells. Despite early successes of charged particle radiotherapy, there is room for further improvement, and much remains to be learned about normal and cancer cell responses to charged particle radiation. PMID:21376738

  18. Toner Display Based on Movement of Tribo-electrically Charged Particles

    Institute of Scientific and Technical Information of China (English)

    Takashi Kitamura

    2004-01-01

    The mechanism of toner display based on an electrical movement of black and white charged particles has been investigated. Two kinds of particles of black and white charged in the different electric polarity are enclosed in two ITO transparent electrodes using an insulating spacer. The particle movement is controlled by the external electric field applied between two transparent electrodes. The black toner is adhered on the electrode by an electrostatic force across the CTL to display a black image. The toners can be put back to the counter electrode by applying a reverse electric field, and a white image is formed. The black and white solid images are displayed by the switch of polarity of applied voltage in toner display cell. The polarity of charge and the value of charge to mass ratio of two particles were measured by observation of the particle separation on the surface-type electrodes and using q/m meter, respectively.

  19. Charge distribution over dust particles configured with size distribution in a complex plasma

    Science.gov (United States)

    Misra, Shikha; Mishra, Sanjay K.

    2016-02-01

    A theoretical kinetic model describing the distribution of charge on the dust particles configured with generalized Kappa size distribution in a complex plasma has been developed. The formulation is based on the manifestation of uniform potential theory with an analytical solution of the master differential equation for the probability density function of dust charge; the number and energy balance of the plasma constituents are utilized in writing the kinetic equations. A parametric study to determine the steady state plasma parameters and the charge distribution corresponding to a size distribution of dust grains in the complex plasma has been made; the numerical results are presented graphically. The charge distribution is seen sensitive to the population of small grains in the particle size distribution and thus in contrast to symmetrical distribution of charge around a mean value for uniform sized grains, the charge distribution in the present case peaks around lower charge.

  20. New Electrically Charged Black Hole in Higher Derivative Gravity as Particle Colliders

    CERN Document Server

    Lin, Kai; Flores-Hidalgo, G; Abdalla, E

    2016-01-01

    In this paper, new electrically charged asymptotically flat black hole solutions are numerically derived in the context of higher derivative gravity. These solutions can be interpreted as generalizations of two different classes of non-charged asymptotically flat spacetimes: Schwarzschild and non-Schwarzschild solutions. The possibility to use these black holes as particle colliders have been analysed. Our results show that the center-of-mass energy of two accelerated charged particles could be arbitrarily high near the event horizon of the extreme charged black hole.

  1. Discrete Element Modeling (DEM) of Triboelectrically Charged Particles: Revised Experiments

    Science.gov (United States)

    Hogue, Michael D.; Calle, Carlos I.; Curry, D. R.; Weitzman, P. S.

    2008-01-01

    In a previous work, the addition of basic screened Coulombic electrostatic forces to an existing commercial discrete element modeling (DEM) software was reported. Triboelectric experiments were performed to charge glass spheres rolling on inclined planes of various materials. Charge generation constants and the Q/m ratios for the test materials were calculated from the experimental data and compared to the simulation output of the DEM software. In this paper, we will discuss new values of the charge generation constants calculated from improved experimental procedures and data. Also, planned work to include dielectrophoretic, Van der Waals forces, and advanced mechanical forces into the software will be discussed.

  2. Excitons or spaced-charged-perturbed fields in irradiated SiO2

    International Nuclear Information System (INIS)

    Flat-band voltage shifts in MOS capacitors irradiated by a kilovolt electron beam have been measured. The relatively low dose conditions employed resulted in the data points being obtained under non-equilibrium conditions and therefore sensitive to the exact manner in which the bias voltage across the sample was cycled. All the results obtained can be explained by considering the transient growth and decay of hole space-charges at the oxide interfaces with the metal electrode and the silicon substrate. No evidence was found to support the role of excitons in generating hole space charge at the oxide/silicon interface as postulated by previous authors. (author)

  3. Exposure to heavy charged particles affects thermoregulation in rats

    Energy Technology Data Exchange (ETDEWEB)

    Kandasamy, S.B.; Hunt, W.A.; Dalton, T.K.; Joseph, J.A.; Harris, A.H. [Armed Forces Radiobiology Research Institute, Bethesda, MD (United States); Rabin, B.M. [Armed Forces Radiobiology Research Institute, Bethesda, MD (United States)]|[Univ. of Maryland, Baltimore, MD (United States)

    1994-09-01

    Rats exposed to 0.1-5 Gy of heavy particles ({sup 56}Fe, {sup 40}Ar, {sup 20}Ne or {sup 4}He) showed dose-dependent changes in body temperature. Lower doses of all particles produced hyperthermia, and higher doses of {sup 20}Ne and {sup 56}Fe produced hypothermia. Of the four HZE particles, {sup 56}Fe particles were the most potent and {sup 4}He particles were the least potent in producing changes in thermoregulation. The {sup 20}Ne and {sup 40}Ar particles produced an intermediate level of change in body temperature. Significantly greater hyperthermia was produced by exposure to 1 Gy of {sup 20}Ne, {sup 40}Ar and {sup 56}Fe particles than by exposure to 1 Gy of {sup 60}Co {gamma} rays. Pretreating rats with the cyclo-oxygenase inhibitor indomethacin attenuated the hyperthermia produced by exposure to 1 Gy of {sup 56}Fe particles, indicating that prostaglandins mediate {sup 56}Fe-particle-induced hyperthermia. The hypothermia produced by exposure to 5 Gy of {sup 56}Fe particles is mediated by histamine and can be attenuated by treatment with the antihistamines mepyramine and cimetidine. 15 refs., 4 figs.

  4. Charge collection efficiency degradation on Si diodes irradiated with high energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Lopez, J., E-mail: fjgl@us.es [CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain); Dpto. Física Atómica, Molecular y Nuclear, Universidad de Sevilla, 41080 Sevilla (Spain); Jimenez-Ramos, M.C. [CNA (U. Sevilla, J. Andalucia, CSIC), Av. Thomas A. Edison 7, 41092 Sevilla (Spain)

    2014-08-01

    The charge collection efficiency (CCE) of several p-type Si diodes has been determined by the Ion Beam Induced Charge (IBIC) technique with 4 MeV protons. In addition, the time evolution of the collected carriers has been recorded as a function of the reverse bias voltage. The diodes were irradiated in our cyclotron with 17 MeV protons and fluences ranging from 3.3 × 10{sup 11} to 1.65 × 10{sup 13} p/cm{sup 2}. The high energy irradiation was selected because of the practically constant value of the proton stopping power across the samples, leading to a uniform vacancy profile with depth. It is observed that the CEE decreases linearly with radiation fluence while the leakage current increases with ion dose. From these results, the diffusion length of minority carriers, the damage constant and the damage coefficient of p-type Si diodes have been evaluated.

  5. Charge collection efficiency degradation on Si diodes irradiated with high energy protons

    International Nuclear Information System (INIS)

    The charge collection efficiency (CCE) of several p-type Si diodes has been determined by the Ion Beam Induced Charge (IBIC) technique with 4 MeV protons. In addition, the time evolution of the collected carriers has been recorded as a function of the reverse bias voltage. The diodes were irradiated in our cyclotron with 17 MeV protons and fluences ranging from 3.3 × 1011 to 1.65 × 1013 p/cm2. The high energy irradiation was selected because of the practically constant value of the proton stopping power across the samples, leading to a uniform vacancy profile with depth. It is observed that the CEE decreases linearly with radiation fluence while the leakage current increases with ion dose. From these results, the diffusion length of minority carriers, the damage constant and the damage coefficient of p-type Si diodes have been evaluated

  6. Density decrease in vanadium-base alloys irradiated in the dynamic helium charging experiment

    Energy Technology Data Exchange (ETDEWEB)

    Chung, H.M.; Galvin, T.M.; Smith, D.L. [Argonne National Laboratory, Chicago, IL (United States)

    1996-04-01

    Combined effects of dynamically charged helium and neutron damage on density decrease (swelling) of V-4Cr-4Ti, V-5Ti, V-3Ti-1Si, and V-8Cr-6Ti alloys have been determined after irradiation to 18-31 dpa at 425-600{degrees}C in the Dynamic helium Charging Experiment (DHCE). To ensure better accuracy in density measurement, broken pieces of tensile specimens {approx} 10 times heavier than a transmission electron microscopy (TEM) disk were used. Density increases of the four alloys irradiated in the DHCE were <0.5%. This small change seems to be consistent with the negligible number density of microcavities characterized by TEM. Most of the dynamically produced helium atoms seem to have been trapped in the grain matrix without significant cavity nucleation or growth.

  7. Constraints on dark matter particles charged under a hidden gauge group from primordial black holes

    International Nuclear Information System (INIS)

    In order to accommodate increasingly tighter observational constraints on dark matter, several models have been proposed recently in which dark matter particles are charged under some hidden gauge group. Hidden gauge charges are invisible for the standard model particles, hence such scenarios are very difficult to constrain directly. However black holes are sensitive to all gauge charges, whether they belong to the standard model or not. Here, we examine the constraints on the possible values of the dark matter particle mass and hidden gauge charge from the evolution of primordial black holes. We find that the existence of the primordial black holes with reasonable mass is incompatible with dark matter particles whose charge to mass ratio is of the order of one. For dark matter particles whose charge to mass ratio is much less than one, we are able to exclude only heavy dark matter in the mass range of 1011 GeV–1016 GeV. Finally, for dark matter particles whose charge to mass ratio is much greater than one, there are no useful limits coming from primordial black holes

  8. Tunneling of Massive Vector Particles From Rotating Charged Black Strings

    OpenAIRE

    Jusufi, Kimet; Övgün, Ali

    2016-01-01

    We study the quantum tunneling of charged massive vector bosons from a charged static and a rotating black string. We apply the standard methods, first we use the WKB approximation and the Hamilton-Jacobi equation, and then we end up with a set of four linear equations. Finally, solving for the radial part by using the determinant of the metric equals zero, the corresponding tunneling rate and the Hawking temperature is recovered in both cases. The tunneling rate deviates from pure thermality...

  9. Charged spinning black holes as accelerators of spinning particles

    CERN Document Server

    Zhang, Yu-Peng; Wei, Shao-Wen; Yang, Jie; Liu, Yu-Xiao

    2016-01-01

    It is well known that some black holes can act as accelerators for particles without spin. Recently, there are some works considering collision of two spinning particles in the background of Schwarzschild and Kerr black holes and it was shown that the spin of the test particles is related to the center-of-mass energy. In this paper we extend the results to some more general cases. We consider Kerr-Newman black holes as accelerators for spinning particles. We derive the center-of-mass energy of the spinning particles and use numerical method to investigate how the center-of-mass energy is affected by the properties of the black holes and spinning particles.

  10. Algorithms for tracking of charged particles in circular accelerators

    International Nuclear Information System (INIS)

    An important problem in accelerator design is the determination of the largest stable betatron amplitude. This stability limit is also known as the dynamic aperture. The equations describing the particle motion are non-linear, and the Linear Lattice Functions cannot be used to compute the stability limits. The stability limits are therefore usually searched for by particle tracking. One selects a set of particles with different betatron amplitudes and tracks them for many turns around the machine. The particles which survive a sufficient number of turns are termed stable. This paper concentrates on conservative systems. For this case the particle motion can be described by a Hamiltonian, i.e. tracking particles means application of canonical transformations. Canonical transformations are equivalent to symplectic mappings, which implies that there exist invariants. These invariants should not be destroyed in tracking

  11. Thermoluminescence of europium-doped zinc oxide exposed to beta particle irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Iriqui R, J. L.; Cruz V, C. [Universidad de Sonora, Departamento de Investigacion en Polimeros y Materiales, Apdo. Postal 130, 83000 Hermosillo, Sonora (Mexico); Bernal, R. [Universidad de Sonora, Departamento de Investigacion en Fisica, Apdo. Postal 5-088, 83000 Hermosillo, Sonora (Mexico); Castano, V. M., E-mail: jorgeiriqui@gimmunison.com [UNAM, Instituto de Fisica, Centro de Fisica Aplicada y Tecnologia Avanzada, Apdo. Postal 1-1010, 76000 Queretaro, Qro. (Mexico)

    2015-10-15

    Full text: Zn O is a promising material for a range of optoelectronics applications, due to its direct wide band gap (E{sub g} ∼3.3 eV at 300 K) and large exciton binding energy (60 MeV). Its applications include UV light emitters, varistors, surface acoustic wave devices, piezoelectric transducers, and chemical and gas sensing. Rare-earth activation of phosphors has long been seen as an effective process since coupling energy into the rare-earth-ion site, either by ionization, charge exchange or a resonance energy process, results in light production. It is reported that Europium modifies the response thermoluminescence (Tl) for pure zinc oxide, when is irradiated with X-ray, created a peak at 365 degrees C. In this work, Zn O:Eu phosphors were synthesized by a chemical method. Some samples were exposed to beta particle irradiation for doses ranging from 1 up to 100 Gy. Tl response as a function of dose is linear throughout the studied dose range. The glow curve exhibits three maxima, centered at 176, 279 and 340 degrees C. The reusability studies obtained after ten repeated cycles of annealing irradiation readout for the Zn O:Eu shows that the variation in the Tl response is ten percent and tends to stabilization. The results indicate that these new Zn O:Eu phosphors are promising detectors and dosimeters for beta radiation. The structural and morphological characterization was carried out by X-ray diffraction and scanning electron microscopy, respectively. (Author)

  12. Asymmetry of Hawking Radiation of Dirac Particles in a Charged Vaidya - de Sitter Black Hole

    CERN Document Server

    Wu, S Q

    2001-01-01

    The Hawking radiation of Dirac particles in a charged Vaidya - de Sitter black hole is investigated by using the method of generalized tortoise coordinate transformation. It is shown that the Hawking radiation of Dirac particles does not exist for $P_1, Q_2$ components, but for $P_2, Q_1$ components it does. Both the location and the temperature of the event horizon change with time. The thermal radiation spectrum of Dirac particles is the same as that of Klein-Gordon particles.

  13. A Dissipative-Particle-Dynamics Model for Simulating Dynamics of Charged Colloid

    OpenAIRE

    Zhou, Jiajia; Schmid, Friederike

    2013-01-01

    A mesoscopic colloid model is developed in which a spherical colloid is represented by many interacting sites on its surface. The hydrodynamic interactions with thermal fluctuations are taken accounts in full using Dissipative Particle Dynamics, and the electrostatic interactions are simulated using Particle-Particle-Particle Mesh method. This new model is applied to investigate the electrophoretic mobility of a charged colloid under an external electric field, and the influence of salt conce...

  14. Study of charged particle production using Omega RICH in WA94 experiment

    International Nuclear Information System (INIS)

    We present preliminary results about charged particle production in S-S collisions at 200GeV/c per nucleon, obtained by WA94 experiment at CERN-SPS. The particle identification has been provided by the Omega RICH; a silicon telescope and an array of multiwire proportional chambers (MWPC) have been used to track particles to the RICH detector. Details about particle tracking and identification procedure are also reported. (orig.)

  15. Charge collection efficiency of an irradiated cryogenic double-p silicon detector

    International Nuclear Information System (INIS)

    We present results on the measurement of the charge collection efficiency of a p+/n/p+ silicon detector irradiated to 1x1015 n/cm2, operated in the temperature range between 80 and 200 K. For comparison, measurements obtained with a standard silicon diode (p+/n/n+), irradiated to the same fluence, are also presented. Both detectors show a dramatic increase of the CCE when operated at temperatures around 130 K. The double-p detector shows a higher CCE regardless of the applied bias and temperature, besides being symmetric with respect to the polarity of the bias voltage. At 130 K and 500 V applied bias the double-p detector shows a CCE of 80%, an unprecedented result for a silicon detector irradiated to such a high dose

  16. Charge collection efficiency of an irradiated cryogenic double-p silicon detector

    Energy Technology Data Exchange (ETDEWEB)

    Borer, K.; Janos, S.; Li, Z.; Dezillie, B.; Da Via, C.; Granata, V.; Casagrande, L. E-mail: luca.casagrande@cern.ch; Boer, R.W.I. de; Lourenco, C.; Niinikoski, T.O.; Palmieri, V.G.; Chapuy, S.; Dimcovski, Z.; Grigoriev, E.; Bell, W.; Devine, S.R.H.; Ruggiero, G.; O' Shea, V.; Smith, K.; Berglund, P.; Boer, W. de; Hauler, F.; Heising, S.; Jungermann, L.; Abreu, M.; Rato, P.; Sousa, P.; Cindro, V.; Mikuz, M.; Zavrtanik, M.; Esposito, A.; Paul, S.; Buontempo, S.; D' Ambrosio, N.; Pagano, S.; Eremin, V.; Verbitskaya, E

    2001-04-21

    We present results on the measurement of the charge collection efficiency of a p{sup +}/n/p{sup +} silicon detector irradiated to 1x10{sup 15} n/cm{sup 2}, operated in the temperature range between 80 and 200 K. For comparison, measurements obtained with a standard silicon diode (p{sup +}/n/n{sup +}), irradiated to the same fluence, are also presented. Both detectors show a dramatic increase of the CCE when operated at temperatures around 130 K. The double-p detector shows a higher CCE regardless of the applied bias and temperature, besides being symmetric with respect to the polarity of the bias voltage. At 130 K and 500 V applied bias the double-p detector shows a CCE of 80%, an unprecedented result for a silicon detector irradiated to such a high dose.

  17. Dependence of charge transfer phenomena during solid-air two-phase flow on particle disperser

    Science.gov (United States)

    Tanoue, Ken-ichiro; Suedomi, Yuuki; Honda, Hirotaka; Furutani, Satoshi; Nishimura, Tatsuo; Masuda, Hiroaki

    2012-12-01

    An experimental investigation of the tribo-electrification of particles has been conducted during solid-air two-phase turbulent flow. The current induced in a metal plate by the impact of polymethylmethacrylate (PMMA) particles in a high-speed air flow was measured for two different plate materials. The results indicated that the contact potential difference between the particles and a stainless steel plate was positive, while for a nickel plate it was negative. These results agreed with theoretical contact charge transfer even if not only the particle size but also the kind of metal plate was changed. The specific charge of the PMMA particles during solid-air two-phase flow using an ejector, a stainless steel branch pipe, and a stainless steel straight pipe was measured using a Faraday cage. Although the charge was negative in the ejector, the particles had a positive specific charge at the outlet of the branch pipe, and this positive charge increased in the straight pipe. The charge decay along the flow direction could be reproduced by the charging and relaxation theory. However, the proportional coefficients in the theory changed with the particle size and air velocity. Therefore, an unexpected charge transfer occurred between the ejector and the branch pipe, which could not be explained solely by the contact potential difference. In the ejector, an electrical current in air might have been produced by self-discharge of particles with excess charge between the nickel diffuser in the ejector and the stainless steel nozzle or the stainless steel pipe due to a reversal in the contact potential difference between the PMMA and the stainless steel. The sign of the current depended on the particle size, possibly because the position where the particles impacted depended on their size. When dual coaxial glass pipes were used as a particle disperser, the specific charge of the PMMA particles became more positive along the particle flow direction due to the contact

  18. Corrections for target absorption of charged particles in wire loaded nuclear emulsions

    International Nuclear Information System (INIS)

    In this paper we discuss how to correct multiplicities, angular and range distributions of charged particles in wire loaded emulsion experiments in order to make the results comparable to those of experiments where ordinary emulsions are used. The corrections arise from particles stopping in the wire or in a shadow zone around the wire and are of importance only for low energy particles. We suggest in the paper a function of the density, the charge and the diameter of the wire target to describe the multiplicity correction for black prong producing particles in hadron-nucleus and nucleus-nucleus reactions above 1 GeV/a.m.u. (author)

  19. Nonlinear dynamics for charges particle beams with a curved axis in the matrix - recursive model

    Energy Technology Data Exchange (ETDEWEB)

    Dymnikov, A.D. [University of St Petersburg, (Russian Federation). Institute of Computational Mathematics and Control Process

    1993-12-31

    In this paper a new matrix and recursive approach has been outlined for treating nonlinear optics of charged particle beams. This approach is a new analytical and computational tool for designers of optimal beam control systems. 9 refs.

  20. Charged particle-induced modification of cellular genomic DNA and gene expression level

    International Nuclear Information System (INIS)

    Aim of this study is to understand cellular and molecular nature of cancer cells survived for long term after charged particle therapy. During the period of 1st year, clonogenic sensitivity of various cancer cell lines against charged particles was investigated by two experimental strategies. Firstly, human glioblastoma cell line, Becker, was investigated for the phenotypic changes after long term survival period (3 weeks). Especially, the cells were revealed to be sensitized toward secondary exposure of charged particles in a way of primary dose-dependence. However, this tendency was clearly eliminated when cells were treated by 5-azacytidine, a DNA methylation inhibitor, before the primary exposure. Thus, epigenetic regulations of cellular genomic DNA were supposed to play important roles in the radiation sensitivity changes of the long-term survived cells. In the second approach, mouse cancer cell line analysis in the presence of 5-azacytidine revealed epigenetic heterogeneity of charged particle sensitivity within the cell population. (author)

  1. Progress on the evaluation of charged particle nuclear reaction data in Sichuan University

    International Nuclear Information System (INIS)

    The evaluations of excitation function of 9 reactions induced by charged particles (p, α, d) have been fulfilled. The evaluated nuclear reactions and the experimental works are presented. The recommended data for each reaction were remarked

  2. Search for particles with unexpected mass and charge in Z decays

    Science.gov (United States)

    Buskilic, D.; Decamp, D.; Goy, C.; Lees, J.-P.; Minard, M.-N.; Mours, B.; Pietrzyk, B.; Alemany, R.; Ariztizabal, F.; Comas, P.; Crespo, J. M.; Delfino, M.; Fernandez, E.; Fernandez-Bosman, M.; Gaitan, V.; Garrido, Ll.; Mattison, T.; Pacheco, A.; Padilla, C.; Pascual, A.; Creanza, D.; de Palma, M.; Farilla, A.; Iaselli, G.; Maggi, G.; Maggi, M.; Natali, S.; Nuzzo, N.; Quattromini, M.; Ranieri, A.; Raso, G.; Romano, F.; Ruggieri, F.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Zito, G.; Chai, Y.; Hu, H.; Huang, D.; Huang, X.; Lin, J.; Wang, T.; Xie, Y.; Xu, D.; Xu, R.; Zhang, J.; Zhang, L.; Zhao, W.; Bauerdick, L. A. T.; Blucher, E.; Bonvicini, G.; Boudreau, J.; Casper, D.; Drevermann, H.; Forty, R. W.; Ganis, G.; Gay, C.; Hagelberg, R.; Harvey, J.; Haywood, S.; Hilgart, J.; Jacobsen, R.; Jost, B.; Knobloch, J.; Lehraus, I.; Lohse, T.; Lusiani, A.; Martinez, M.; Mato, P.; Meinhard, H.; Mitten, A.; Miotto, A.; Miquel, R.; Moser, H.-G.; Palazzi, P.; Perlas, J. A.; Pusztaszeri, J.-F.; Ranjard, F.; Redlinger, G.; Rolandi, L.; Rothberg, J.; Ruan, T.; Saich, M.; Schlatter, D.; Schmelling, M.; Sefkow, F.; Tejessy, W.; Wachsmuth, H.; Wiedenmann, W.; Wildish, T.; Witzeling, W.; Wotschack, J.; Ajaltouni, Z.; Badaud, F.; Bardadin-Otwinowska, M.; El Fellous, R.; Falvard, A.; Gay, P.; Guicheney, C.; Henrard, P.; Jousset, J.; Michel, B.; Montret, J.-C.; Pallin, D.; Perret, P.; Podlyski, F.; Proriol, J.; Prulhière, F.; Saadi, F.; Fearnley, T.; Hansen, J. D.; Hansen, J. R.; Hansen, P. H.; Møllerud, R.; Nilsson, B. S.; Efthymiopoulos, I.; Kyriakis, A.; Simopoulou, E.; Vayaki, A.; Zachariadou, K.; Badier, J.; Blondel, A.; Bonneaud, G.; Brient, J. C.; Fouque, G.; Orteu, S.; Rougé, A.; Rumpf, M.; Tanaka, R.; Verderi, M.; Videau, H.; Candlin, D. J.; Parsons, M. I.; Veitch, E.; Moneta, L.; Parrini, G.; Corden, M.; Georgiopoulos, C.; Ikeda, M.; Lannutti, J.; Levinthal, D.; Mermikides, M.; Sawyer, L.; Wasserbaech, S.; Antonelli, A.; Baldini, R.; Bencivenni, G.; Bologna, G.; Bossi, F.; Campana, P.; Capon, G.; Cerutti, F.; Chiarella, V.; D'Ettorre-Piazzoli, B.; Felici, G.; Laurelli, P.; Mannocchi, G.; Murtas, F.; Murtas, G. P.; Passalacqua, L.; Pepe-Altarelli, M.; Picchi, P.; Colrain, P.; Ten Have, I.; Lynch, J. G.; Maitland, W.; Morton, W. T.; Raine, C.; Reeves, P.; Scarr, J. M.; Smith, K.; Smith, M. G.; Thompson, A. S.; Turnbull, R. M.; Brandl, B.; Braun, O.; Geweniger, C.; Hanke, P.; Hepp, V.; Kluge, E. E.; Maumary, Y.; Putzer, A.; Rensch, B.; Stahl, A.; Tittel, K.; Wunsch, M.; Belk, A. T.; Beuselinck, R.; Binnie, D. M.; Cameron, W.; Cattaneo, M.; Colling, D. J.; Dornan, P. J.; Dugeay, S.; Greene, A. M.; Hassard, J. F.; Lieske, N. M.; Nash, J.; Payne, D. G.; Phillips, M. J.; Sedgbeer, J. K.; Tomalin, I. R.; Wright, A. G.; Girtler, P.; Kneringer, E.; Kuhn, D.; Rudolph, G.; Bowdery, C. K.; Brodbeck, T. J.; Finch, A. J.; Foster, F.; Hughes, G.; Jackson, D.; Keemer, N. R.; Nuttall, M.; Patel, A.; Sloan, T.; Snow, S. W.; Whelan, E. P.; Kleinknecht, K.; Raab, J.; Renk, B.; Sander, H.-G.; Schmidt, H.; Steeg, F.; Walther, S. M.; Wanke, R.; Wolf, B.; Aubert, J.-J.; Bencheikh, A. M.; Benchouk, C.; Bonissent, A.; Carr, J.; Coyle, P.; Drinkard, J.; Etienne, F.; Nicod, D.; Papalexiou, S.; Payre, P.; Roos, L.; Rousseau, D.; Schwemling, P.; Talby, M.; Adlung, S.; Assmann, R.; Bauer, C.; Blum, W.; Brown, D.; Catteneo, P.; Dehning, B.; Dietl, H.; Dydak, F.; Frank, M.; Halley, A. W.; Lauber, J.; Lütjens, G.; Lutz, G.; Männer, W.; Richter, R.; Rotscheidt, H.; Schröder, J.; Schwarz, A. S.; Settles, R.; Seywerd, H.; Stierlin, U.; Stiegler, U.; St. Denis, R.; Wolf, G.; Boucrot, J.; Callot, O.; Cordier, A.; Davier, M.; Duflot, L.; Grivaz, J.-F.; Heusse, Ph.; Jaffe, D. E.; Janot, P.; Kim, D. W.; Le Diberder, F.; Lefrançois, J.; Lutz, A.-M.; Schune, M.-H.; Veillet, J.-J.; Videau, I.; Zhang, Z.; Abbaneo, D.; Bagliesi, G.; Batignani, G.; Bosisio, L.; Bottigli, U.; Bozzi, C.; Calderini, G.; Carpinelli, M.; Ciocci, M. A.; dell'Orso, R.; Ferrante, I.; Fidecaro, F.; Foà, L.; Focardi, E.; Forti, F.; Giassi, A.; Giorgi, M. A.; Gregorio, A.; Ligabue, F.; Mannelli, E. B.; Marrocchesi, P. S.; Messineo, A.; Palla, F.; Rizzo, G.; Sanguinetti, G.; Spagnolo, P.; Steinberger, J.; Tenchini, R.; Tonelli, G.; Triggiani, G.; Vannini, C.; Venturi, A.; Verdini, P. G.; Walsh, J.; Betteridge, A. P.; Carter, J. M.; Green, M. G.; March, P. V.; Mir, Ll. M.; Medcalf, T.; Quazi, I. S.; Strong, J. A.; West, L. R.; Botterill, D. R.; Clifft, R. W.; Edgecock, T. R.; Edwards, M.; Fisher, S. M.; Jones, T. J.; Norton, P. R.; Salmon, D. P.; Thompson, J. C.; Bloch-Devaux, B.; Colas, P.; Duarte, H.; Kozanecki, W.; Lançon, E.; Lemaire, M. C.; Locci, E.; Perez, P.; Perrier, F.; Rander, J.; Renardy, J.-F.; Rosowsky, A.; Roussarie, A.; Schuller, J.-P.; Schwindling, J.; Si Mohand, D.; Vallage, B.; Johnson, R. P.; Litke, A. M.; Taylor, G.; Wear, J.; Ashman, J. G.; Babbage, W.; Booth, C. N.; Buttar, C.; Carney, R. E.; Cartwright, S.; Combley, F.; Hatfield, F.; Thompson, L. F.; Barberio, E.; Böhrer, A.; Brandt, S.; Cowan, G.; Grupen, C.; Lutters, G.; Rivera, F.; Schäfer, U.; Smolik, L.; della Marina, R.; Giannini, G.; Gobbo, B.; Ragusa, F.; Bellantoni, L.; Chen, W.; Cinabro, D.; Conway, J. S.; Cowen, D. F.; Feng, Z.; Ferguson, D. P. S.; Gao, Y. S.; Grahl, J.; Harton, J. L.; Jared, R. C.; Leclaire, B. W.; Lishka, C.; Pan, Y. B.; Pater, J. R.; Saadi, Y.; Sharma, V.; Schmitt, M.; Shi, Z. H.; Walsh, A. M.; Weber, F. V.; Lan Wu, Sau; Wu, X.; Zheng, M.; Zobernig, G.

    1993-04-01

    During 1989 and 1990 over 180 000 hadronic and leptonic events, corresponding to 8 pb-1 of luminosity, were collected by the ALEPH detector in a scan of the Z peak at the e+e- collider LEP. This letter reports the results of a search in these data for particles with unexpected mass and charge by measurement of the ionization energy loss of charged tracks in the ALEPH TPC central tracking detector. The mass limits for the pair production of fractionally charged particles and of heavy, long lived charged particles are extended to 43 GeV/c2 at 90% confidence level. If single production of a heavy particle is considered, the mass limit is extended to more than 70 GeV/c2. Supported by the US Department of Energy, contract DE-AC02-76ER00881.

  3. Measurements of the Charged­ Particle distributions with the ATLAS detector

    CERN Document Server

    Cairo, Valentina; The ATLAS collaboration

    2016-01-01

    Inclusive charged ­particle measurements at hadron colliders probe the low­ energy non­perturbative region of QCD. The ATLAS collaboration has measured the charged­ particle multiplicity and its dependence on transverse momentum and pseudorapidity in special data sets with low LHC beam currents, recorded at center­-of­-mass energies of 8 TeV and 13 TeV. The new precise measurements at 8 TeV cover a wide spectrum using charged­ particle selections with minimum transverse momentum of both 100 MeV and 500 MeV and in various phase space regions of low and high charged particle multiplicities. The measurements at 13 TeV present the first detailed studies with a minimum transverse momentum of both 100 MeV and 500 MeV. The measurements are compared with predictions of various MC generators and are found to provide strong constraints on these.

  4. Ground state configurations of charged particles in a disk at zero temperature

    Science.gov (United States)

    Cerkaski, M.; Nazmitdinov, R. G.

    2014-11-01

    We discuss a novel theoretical approach which explains the self-organization of charged particles in a disk geometry. It allows to calculate readily equilibrium configurations for n <= 400 with a remarkable accuracy, when compared with the molecular dynamics calculations.

  5. Stimulated Brillouin scattering of an electromagnetic wave in weakly magnetized plasma with variably charged dust particles

    Indian Academy of Sciences (India)

    Sourabh Bal; M Bose

    2009-10-01

    We have investigated analytically the stimulated Brillouin scattering (SBS) of an electromagnetic wave in non-dissipative weakly magnetized plasma in the presence of dust particles with variable charge.

  6. Maximizing Ion Current by Space Charge Neutralization using Negative Ions and Dust Particles

    International Nuclear Information System (INIS)

    Ion current extracted from an ion source (ion thruster) can be increased above the Child-Langmuir limit if the ion space charge is neutralized. Similarly, the limiting kinetic energy density of the plasma flow in a Hall thruster might be exceeded if additional mechanisms of space charge neutralization are introduced. Space charge neutralization with high-mass negative ions or negatively charged dust particles seems, in principle, promising for the development of a high current or high energy density source of positive light ions. Several space charge neutralization schemes that employ heavy negatively charged particles are considered. It is shown that the proposed neutralization schemes can lead, at best, only to a moderate but nonetheless possibly important increase of the ion current in the ion thruster and the thrust density in the Hall thruster

  7. Effects of Gamma Irradiation and Silver Nano Particles on Microbiological Characteristics of Saffron, Using Hurdle Technology

    OpenAIRE

    Hamid Sales, E.; Motamedi Sedeh, F.; Rajabifar, S.

    2011-01-01

    Saffron, a plant from the Iridaceae family, is the world’s most expensive spice. Gamma irradiation and silver nano particles whose uses are gradually increasing worldwide, have positive effects on preventing decay by sterilizing the microorganisms and by improving the safety without compromising the nutritional properties and sensory quality of the foods. In the present study combination effects of gamma irradiation and silver nano particles packaging on the microbial contamination of saffron...

  8. Second Research Coordination Meeting on Heavy Charged-Particle Interaction Data for Radiotherapy. Summary Report

    International Nuclear Information System (INIS)

    A summary is given of the 2nd Research Coordination Meeting (RCM) on Heavy Charged-Particle Interaction Data for Radiotherapy. The programme to compile and evaluate charged-particle nuclear data for therapeutic applications was reviewed. Technical discussions and the resulting work plan of the Coordinated Research Programme are summarized, along with planned actions and deadlines. Participants' reports at the 2nd RCM are also included in this report. (author)

  9. Tunneling of massive and charged particles from noncommutative Reissner-Nordstr\\"{o}m black hole

    OpenAIRE

    Nozari, Kourosh; Islamzadeh, Sara

    2012-01-01

    Massive charged and uncharged particles tunneling from commutative Reissner-Nordstrom black hole horizon has been studied with details in literature. Here, by adopting the coherent state picture of spacetime noncommutativity, we study tunneling of massive and charged particles from a noncommutative inspired Reissner-Nordstrom black hole horizon. We show that Hawking radiation in this case is not purely thermal and there are correlations between emitted modes. These correlations may provide a ...

  10. CHANTI: a fast and efficient charged particle veto detector for the NA62 experiment at CERN

    International Nuclear Information System (INIS)

    The design, construction and test of a charged particle detector made of scintillation counters read by Silicon Photomultipliers (SiPM) is described. The detector, which operates in vacuum and is used as a veto counter in the NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a spatial resolution of ∼2.5 mm and an efficiency very close to 1 for penetrating charged particles

  11. CHANTI: a fast and efficient charged particle veto detector for the NA62 experiment at CERN

    Science.gov (United States)

    Ambrosino, F.; Capussela, T.; Di Filippo, D.; Massarotti, P.; Mirra, M.; Napolitano, M.; Palladino, V.; Saracino, G.; Roscilli, L.; Vanzanella, A.; Corradi, G.; Tagnani, D.; Paglia, U.

    2016-03-01

    The design, construction and test of a charged particle detector made of scintillation counters read by Silicon Photomultipliers (SiPM) is described. The detector, which operates in vacuum and is used as a veto counter in the NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a spatial resolution of ~2.5 mm and an efficiency very close to 1 for penetrating charged particles.

  12. A parametrisation of the energy loss distributions of charged particles and its applications for silicon detectors

    CERN Document Server

    Sikler, Ferenc

    2012-01-01

    The energy loss distribution of charged particles in silicon is approximated by a simple analytical parametrization. Its use is demonstrated through several examples. With the help of energy deposits in sensing elements of the detector, the position of track segments and the corresponding deposited energy are estimated with improved accuracy and less bias. The parametrization is successfully used to estimate the energy loss rate of charged particles, and it is applied to detector gain calibration tasks.

  13. Trace element analysis in thick targets by charge particle induced x-rays

    International Nuclear Information System (INIS)

    The quantitative determination of trace impurities in a thick target through detection of x-rays produced by an accelerated charged particle involves a continous variation of energy of the charged particle, from the incident energy to a final minimum value. Hence the expression for the x-ray yield has to be summed over a continuous range of energies. A method is described to reduce this infinite sum into a finite sum

  14. Influence of the fringe field on moving of the charged particles in flat and cylindrical capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Doskeyev, G.A.; Edenova, O.A. [Aktobe State University named after K. Zhubanov, Br. Zhubanov Street 263, 030000 Aktobe (Kazakhstan); Spivak-Lavrov, I.F., E-mail: spivakif@rambler.ru [Aktobe State University named after K. Zhubanov, Br. Zhubanov Street 263, 030000 Aktobe (Kazakhstan)

    2011-07-21

    This paper describes different analytic approaches to describe the fringe fields of flat and cylindrical capacitor structures. A method for the calculation of deflection of charged particles from the optical axis is developed. The behavior of a charged particle beam in a flat capacitor is approximated by using a sharp cut-off boundary for the field, which has the provision of taking fringe fields into account.

  15. Influence of the fringe field on moving of the charged particles in flat and cylindrical capacitors

    International Nuclear Information System (INIS)

    This paper describes different analytic approaches to describe the fringe fields of flat and cylindrical capacitor structures. A method for the calculation of deflection of charged particles from the optical axis is developed. The behavior of a charged particle beam in a flat capacitor is approximated by using a sharp cut-off boundary for the field, which has the provision of taking fringe fields into account.

  16. A stochastic-hydrodynamic model of halo formation in charged particle beams

    OpenAIRE

    Petroni, Nicola Cufaro; De Martino, Salvatore; De Siena, Silvio; Illuminati, Fabrizio

    2003-01-01

    The formation of the beam halo in charged particle accelerators is studied in the framework of a stochastic-hydrodynamic model for the collective motion of the particle beam. In such a stochastic-hydrodynamic theory the density and the phase of the charged beam obey a set of coupled nonlinear hydrodynamic equations with explicit time-reversal invariance. This leads to a linearized theory that describes the collective dynamics of the beam in terms of a classical Schr\\"odinger equation. Taking ...

  17. Effect of charged particle's multiplicity fluctuations on flow harmonics in even-by-event hydrodynamics

    OpenAIRE

    Chaudhuri, A. K.

    2012-01-01

    In nucleon-nucleon collisions, charged particle's multiplicity fluctuates. We have studied the effect of multiplicity fluctuation on flow harmonics in nucleus-nucleus collision in event-by-event hydrodynamics. Assuming that the charged particle's multiplicity fluctuations are governed by the negative binomial distribution, the Monte-Carlo Glauber model of initial condition is generalised to include the fluctuations. Explicit simulations with the generalised Monte-Carlo Glauber model initial c...

  18. CHANTI: a Fast and Efficient Charged Particle Veto Detector for the NA62 Experiment at CERN

    CERN Document Server

    Ambrosino, F; Di Filippo, D; Massarotti, P; Mirra, M; Napolitano, M; Palladino, V; Saracino, G; Roscilli, L; Vanzanella, A; Corradi, G; Tagnani, D; Paglia, U

    2016-01-01

    The design, construction and test of a charged particle detector made of scintillation counters read by Silicon Photomultipliers (SiPM) is described. The detector, which operates in vacuum and is used as a veto counter in the NA62 experiment at CERN, has a single channel time resolution of 1.14 ns, a spatial resolution of ~2.5 mm and an efficiency very close to 1 for penetrating charged particles.

  19. Preliminary study for the detection of neutrons in heavy-ion collisions with charged particle detectors

    OpenAIRE

    Auditore L.; Pagano A.; Russotto P.

    2015-01-01

    At Laboratori Nazionali del Sud (LNS) the CHIMERA 4π multidetector has been designed and setup to detect charged particles emitted in heavy ion collisions at intermediate energies. Properties and performances of CHIMERA have been widely demonstrated by published results obtained in the performed experiments. Moreover, in recent years, a new charged particle detector (ChPD) for correlation studies (FARCOS) has been designed, and recently a first prototype has been coupled to CHIMERA, in order ...

  20. Measurements of charged-particle inclusive distributions in hadronic decays of the Z boson

    International Nuclear Information System (INIS)

    We have measured inclusive distributions for charged particles in hadronic decays of the Z boson. The variables chosen for study were charged-particle multiplicity, scaled momentum, and momenta transverse to the sphericity axes. The distributions have been corrected for detector effects and are compared with data from e+e- annihilation at lower energies and with the predictions of several QCD-based models. The data are in reasonable agreement with expectations