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Sample records for irradiating high-z targets

  1. Time-resolved x-ray spectra of laser irradiated high-Z targets

    International Nuclear Information System (INIS)

    Lee, P.H.Y.; Attwood, D.T.; Boyle, M.J.; Campbell, E.M.; Coleman, L.C.; Kornblum, H.N.

    1977-01-01

    Recent results obtained by using the Livermore 15 psec x-ray streak camera to record x-ray emission from laser-irradiated high-z targets in the 1-20 keV range are reported. Nine to eleven K-edge filter channels were used for the measurements. In the lower energy channels, a dynamic range of x-ray emission intensity of better than three orders of magnitude have been recorded. Data will be presented which describe temporally and spectrally resolved x-ray spectra of gold disk targets irradiated by laser pulses from the Argus facility, including the temporal evolution of the superthermal x-ray tail

  2. The interactions of laser beam with high Z solid target

    International Nuclear Information System (INIS)

    Peng Huimin; Zhang Guoping; Sheng Jiatian

    1990-01-01

    The 1-D non-LTE radiative hydrodynamic laser irradiated code JB-19 is used to calculate the laser-produced plasma conditions of high z gold disk. Following physical processes are considered: bremsstrahlung effect, radiative ionization and recombination, collisional ionization by electrons and three-body recombination, collisional excitation and de-excitation by electrons, radiative line emission and absorption and Compton scattering. A gaussian laser pulse with wavelength 1.06 μm, FWHM 600 ps and peak intensity 3 x 10 14 W/cm 2 is used to irradiate 20 μm thick gold disk. The computational results for laser-produced plasma conditions and the absorption efficiency and laser-x-rays conversion efficiency for gold disk are shown

  3. Theoretical interpretation of high-Z discs irradiated with 1.06 μ laser light

    International Nuclear Information System (INIS)

    Rosen, M.D.; Mead, W.C.; Thomson, J.J.; Kruer, W.L.

    1978-01-01

    High Z discs have been irradiated with 1.06 μ laser light at intensities between 7 x 10 13 and 3 x 10 15 W/cm, and pulse lengths between 200 and 1000 ps. Due to the high Z, inverse bremsstrahlung becomes an important absorption effect and competes strongly with resonance absorption and stimulated scattering. We find that inhibited electron thermal conduction and non-LTE ionization physics are important. Their inclusion in the LASNEX modeling results in steepened temperature and density profiles near critical, thus producing a several keV underdense corona. These conditions bring what would otherwise be 100% inverse bremsstrahlung absorption down to the experimentally observed values (50% at 10 14 W/cm). The non-LTE physics is essential to correctly compute the level populations of the high Z atoms moving rapidly through a steep density gradient into the corona. This modeling also shows that x-rays are emitted in a thin overdense region, and on a time scale 50% longer than the laser pulse. Both of these effects are seen in the experiments

  4. Effects of thin high-Z layers on the hydrodynamics of laser-accelerated plastic targets

    International Nuclear Information System (INIS)

    Obenschain, S.P.; Colombant, D.G.; Karasik, M.; Pawley, C.J.; Serlin, V.; Schmitt, A.J.; Weaver, J.L.; Gardner, J.H.; Phillips, L.; Aglitskiy, Y.; Chan, Y.; Dahlburg, J.P.; Klapisch, M.

    2002-01-01

    Experimental results and simulations that study the effects of thin metallic layers with high atomic number (high-Z) on the hydrodynamics of laser accelerated plastic targets are presented. These experiments employ a laser pulse with a low-intensity foot that rises into a high-intensity main pulse. This pulse shape simulates the generic shape needed for high-gain fusion implosions. Imprint of laser nonuniformity during start up of the low intensity foot is a well-known seed for hydrodynamic instability. Large reductions are observed in hydrodynamic instability seeded by laser imprint when certain minimum thickness gold or palladium layers are applied to the laser-illuminated surface of the targets. The experiment indicates that the reduction in imprint is at least as large as that obtained by a 6 times improvement in the laser uniformity. Simulations supported by experiments are presented showing that during the low intensity foot the laser light can be nearly completely absorbed by the high-Z layer. X rays originating from the high-Z layer heat the underlying lower-Z plastic target material and cause large buffering plasma to form between the layer and the accelerated target. This long-scale plasma apparently isolates the target from laser nonuniformity and accounts for the observed large reduction in laser imprint. With onset of the higher intensity main pulse, the high-Z layer expands and the laser light is transmitted. This technique will be useful in reducing laser imprint in pellet implosions and thereby allow the design of more robust targets for high-gain laser fusion

  5. Study of high-Z target plate materials in the divertor of ASDEX-Upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Hirsch, S; Asmussen, K; Engelhardt, W; Field, A R; Fussmann, G; Lieder, G; Naujoks, D; Neu, R; Radtke, R; Wenzel, U [Max-Planck-Institut fuer Plasmaphysik, Garching (Germany)

    1994-12-31

    The reduction of divertor tile erosion is a challenging problem in present and future tokamaks. Until now, graphite has almost exclusively been used for divertor plates, and it is estimated that unacceptable amounts of material would be eroded under reactor relevant conditions where power fluxes to the target plates as high as 20 MW/m{sup 2} are expected. In a high-recycling divertor with relatively low temperature (5 eVhigh-Z materials, e.g. tungsten, offer a possible solution to the target erosion problem. The reason is that the sputtering rates for these materials are extremely low under low temperature conditions. In addition, at high density the ionization lengths can be smaller than the gyro-radius leading to a high probability for prompt redeposition of the eroded ions. To provide a test of the suitability of high-Z materials for the divertor plates, in-situ studies of the erosion of various divertor target materials have been performed by means of passive spectroscopy. From our spectroscopic observations we infer that under high density divertor conditions the advantages of high-Z materials become fully efficient. (author) 6 refs., 2 figs.

  6. K-α emission form medium and high-Z materials irradiated by femtosecond laser pulses

    International Nuclear Information System (INIS)

    Limpouch, J.; Klimo, O.; Zhavoronkov, N.; Andreev, A.A.

    2006-01-01

    Complete test of publication follows. Fast electrons are created at the target surface during the interaction of high intensity ultra short laser pulses with solids. Fast electrons penetrate deep into the target where they generate K-α and Bremsstrahlung radiation. Generated high brightness K-α pulses offer the prospect of creating a cheap and compact X-ray source, posing a promising alternative to synchrotron radiation, e.g. in medical application and in material science. With an increase in laser intensity, efficient X-ray emission in the multi-keV range with pulse duration shorter than few picoseconds is expected. This short incoherent but monochromatic X-ray emission synchronized with laser pulses may be used for time-resolved measurements. Acceleration of fast electrons, their transport and K-α photon generation and emission from the target surface in both forward and backward directions are studied here numerically. The results are compared to recent experiments studying K-α emission from the front and rear surface of copper foil targets of various thicknesses and for various parameters of the laser plasma interaction. One-dimensional PIC simulations coupled with 3D time-resolved Monte Carlo simulations show that account of ionization processes and of density profile formed by laser ASE emission is essential for reliable explanation of experimental data. While sub-relativistic intensities are optimum for laser energy transformation into K-α emission for medium-Z targets, relativistic laser intensities have to be used for hard X-ray generation in high-Z materials. The cross-section for K-α shell ionization of high-Z elements by electrons increases or remains approximately constant within a factor of two at relativistic electron energies up to electron energies in the 100-MeV range. Moreover, the splitting ratio of K-α photon emission to Auger electron emission is favorable for high-Z materials, and thus efficient K-α emission is possible. In our

  7. MULTI-KEV X-Ray Yields From High-Z Gas Targets Fielded At Omega

    International Nuclear Information System (INIS)

    Kane, J.O.; Fournier, K.B.; May, M.J.; Colvin, J.D.; Thomas, C.A.; Marrs, R.E.; Compton, S.M.; Moody, J.D.; Bond, E.J.; Davis, J.F.

    2010-01-01

    The authors report on modeling of x-ray yield from gas-filled targets shot at the OMEGA laser facility. The OMEGA targets were 1.8 mm long, 1.95 mm in diameter Be cans filled with either a 50:50 Ar:Xe mixture, pure Ar, pure Kr or pure Xe at ∼ 1 atm. The OMEGA experiments heated the gas with 20 kJ of 3ω (∼ 350 nm) laser energy delivered in a 1 ns square pulse. the emitted x-ray flux was monitored with the x-ray diode based DANTE instruments in the sub-keV range. Two-dimensional x-ray images (for energies 3-5 keV) of the targets were recorded with gated x-ray detectors. The x-ray spectra were recorded with the HENWAY crystal spectrometer at OMEGA. Predictions are 2D r-z cylindrical with DCA NLTE atomic physics. Models generally: (1) underpredict the Xe L-shell yields; (2) overpredict the Ar K-shell yields; (3) correctly predict the Xe thermal yields; and (4) greatly underpredict the Ar thermal yields. However, there are spreads within the data, e.g. the DMX Ar K-shell yields are correctly predicted. The predicted thermal yields show strong angular dependence.

  8. Heating, Hydrodynamics, and Radiation From a Laser Heated Non-LTE High-Z Target

    Science.gov (United States)

    Gray, William; Foord, M. E.; Schneider, M. B.; Barrios, M. A.; Brown, G. V.; Heeter, R. F.; Jarrott, L. C.; Liedahl, D. A.; Marley, E. V.; Mauche, C. W.; Widmann, K.

    2016-10-01

    We present 2D R-z simulations that model the hydrodynamics and x-ray output of a laser heated, tamped foil, using the rad-hydro code LASNEX. The foil consists of a thin (2400 A) cylindrical disk of iron/vanadium/gold that is embedded in a thicker Be tamper. The simulations utilize a non-LTE detailed configuration (DCA) model, which generates the emission spectra. Simulated pinhole images are compared with data, finding qualitative agreement with the time-history of the face-on emission profiles, and exhibiting an interesting reduction in emission size over a few ns time period. Furthermore, we find that the simulations recover similar burn through times in both the target and Be tamper as measured by a time-dependent filtered x-ray detector (DANTE). Additional results and characterization of the experimental plasma will be presented. This work performed under the auspices of U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  9. Shiva target irradiation facility

    International Nuclear Information System (INIS)

    Manes, K.R.; Ahlstrom, H.G.; Coleman, L.W.; Storm, E.K.; Glaze, J.A.; Hurley, C.A.; Rienecker, F.; O'Neal, W.C.

    1977-01-01

    The first laser/plasma studies performed with the Shiva laser system will be two sided irradiations extending the data obtained by other LLL lasers to higher powers. The twenty approximately 1 TW laser pulses will reach the target simultaneously from above and below in nested pentagonal clusters. The upper and lower clusters of ten beams each are radially polarized so that they strike the target in p-polarization and maximize absorption. This geometry introduces laser system isolation problems which will be briefly discussed. The layout and types of target diagnostics will be described and a brief status report on the facility given

  10. Uranium briquettes for irradiation target

    Energy Technology Data Exchange (ETDEWEB)

    Saliba-Silva, Adonis Marcelo; Garcia, Rafael Henrique Lazzari; Martins, Ilson Carlos; Carvalho, Elita Fontenele Urano de; Durazzo, Michelangelo, E-mail: saliba@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    Direct irradiation on targets inside nuclear research or multiple purpose reactors is a common route to produce {sup 99}Mo-{sup 99m}Tc radioisotopes. Nevertheless, since the imposed limits to use LEU uranium to prevent nuclear armament production, the amount of uranium loaded in target meats has physically increased and new processes have been proposed for production. Routes using metallic uranium thin film and UAl{sub x} dispersion have been used for this purpose. Both routes have their own issues, either by bringing difficulties to disassemble the aluminum case inside hot cells or by generating great amount of alkaline radioactive liquid rejects. A potential route might be the dispersion of powders of LEU metallic uranium and nickel, which are pressed as a blend inside a die and followed by pulse electroplating of nickel. The electroplating provides more strength to the briquettes and creates a barrier for gas evolution during neutronic disintegration of {sup 235}U. A target briquette platted with nickel encapsulated in an aluminum case to be irradiated may be an alternative possibility to replace other proposed targets. This work uses pulse Ni-electroplating over iron powder briquette to simulate the covering of uranium by nickel. The following parameters were applied 10 times for each sample: 900Hz, -0.84A/square centimeters with duty cycle of 0.1 in Watts Bath. It also presented the optical microscopy analysis of plated microstructure section. (author)

  11. Uranium briquettes for irradiation target

    International Nuclear Information System (INIS)

    Saliba-Silva, Adonis Marcelo; Garcia, Rafael Henrique Lazzari; Martins, Ilson Carlos; Carvalho, Elita Fontenele Urano de; Durazzo, Michelangelo

    2011-01-01

    Direct irradiation on targets inside nuclear research or multiple purpose reactors is a common route to produce 99 Mo- 99m Tc radioisotopes. Nevertheless, since the imposed limits to use LEU uranium to prevent nuclear armament production, the amount of uranium loaded in target meats has physically increased and new processes have been proposed for production. Routes using metallic uranium thin film and UAl x dispersion have been used for this purpose. Both routes have their own issues, either by bringing difficulties to disassemble the aluminum case inside hot cells or by generating great amount of alkaline radioactive liquid rejects. A potential route might be the dispersion of powders of LEU metallic uranium and nickel, which are pressed as a blend inside a die and followed by pulse electroplating of nickel. The electroplating provides more strength to the briquettes and creates a barrier for gas evolution during neutronic disintegration of 235 U. A target briquette platted with nickel encapsulated in an aluminum case to be irradiated may be an alternative possibility to replace other proposed targets. This work uses pulse Ni-electroplating over iron powder briquette to simulate the covering of uranium by nickel. The following parameters were applied 10 times for each sample: 900Hz, -0.84A/square centimeters with duty cycle of 0.1 in Watts Bath. It also presented the optical microscopy analysis of plated microstructure section. (author)

  12. Method for the irradiation of single targets

    International Nuclear Information System (INIS)

    Krimmel, E.; Dullnig, H.

    1977-01-01

    The invention pertains to a system for the irradiation of single targets with particle beams. The targets all have frames around them. The system consists of an automatic advance leading into a high-vacuum chamber, and a positioning element which guides one target after the other into the irradiation position, at right angles to the automatic advance, and back into the automatic advance after irradiation. (GSCH) [de

  13. Experimental study on ablative stabilization of Rayleigh-Taylor instability of laser-irradiated targets

    Science.gov (United States)

    Shigemori, Keisuke; Sakaiya, Tatsuhiko; Otani, Kazuto; Fujioka, Shinsuke; Nakai, Mitsuo; Azechi, Hiroshi; Shiraga, Hiroyuki; Tamari, Yohei; Okuno, Kazuki; Sunahara, Atsushi; Nagatomo, Hideo; Murakami, Masakatsu; Nishihara, Katsunobu; Izawa, Yasukazu

    2004-09-01

    Hydrodynamic instabilities are key issues of the physics of inertial confinement fusion (ICF) targets. Among the instabilities, Rayleigh-Taylor (RT) instability is the most important because it gives the largest growth factor in the ICF targets. Perturbations on the laser irradiated surface grow exponentially, but the growth rate is reduced by ablation flow. The growth rate γ is written as Takabe-Betti formula: γ = [kg/(1+kL)]1/2-βkm/pa, where k is wave number of the perturbation, g is acceleration, L is density scale-length, β is a coefficient, m is mass ablation rate per unit surface, and ρa is density at the ablation front. We experimentally measured all the parameters in the formula for polystyrene (CH) targets. Experiments were done on the HIPER laser facility at Institute of Laser Engineering, Osaka University. We found that the β value in the formula is ~ 1.7, which is in good agreements with the theoretical prediction, whereas the β for certain perturbation wavelengths are larger than the prediction. This disagreement between the experiment and the theory is mainly due to the deformation of the cutoff surface, which is created by non-uniform ablation flow from the ablation surface. We also found that high-Z doped plastic targets have multiablation structure, which can reduce the RT growth rate. When a low-Z target with high-Z dopant is irradiated by laser, radiation due to the high-Z dopant creates secondary ablation front deep inside the target. Since, the secondary ablation front is ablated by x-rays, the mass ablation rate is larger than the laser-irradiated ablation surface, that is, further reduction of the RT growth is expected. We measured the RT growth rate of Br-doped polystyrene targets. The experimental results indicate that of the CHBr targets show significantly small growth rate, which is very good news for the design of the ICF targets.

  14. Observation of material, thickness, and bremsstrahlung x-ray intensity dependent effects in moderate and high Z targets in a gamma and x-ray LIDAR experiment

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Xiaodong, E-mail: xzhang39@utk.edu [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Ayaz-Maierhafer, Birsen; Laubach, Mitchell A. [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Hayward, Jason P. [Department of Nuclear Engineering, University of Tennessee, TN 37996 (United States); Oak Ridge National Lab, Oak Ridge, TN 37831 (United States)

    2015-06-01

    A high energy gamma and x-ray LIDAR system consisting of a fast pulse (~50 ps, FWHM) LINAC and a Cherenkov detection system was used to investigate response differences among materials, their thicknesses, and bremsstrahlung x-ray intensities. The energies and pulse width of electrons used to produce bremsstrahlung x-rays were set at 20 or 40 MeV and 50 ps FWHM duration, respectively. The Cherenkov detector was built with a fused silica glass optically coupled to a 51 mm fast timing photomultiplier tube, which has an intrinsic energy threshold of 340.7 keV for Compton backscattered gammas. Such a fast detection system yields a coincidence resolving time of 93 ps FWHM, which is equivalent to a depth resolving capability of about 3 cm FWHM. The thicknesses of iron and lead targets were varied from 1 in. to 7 in. with a step of 1 in., and the thicknesses of DU were varied from 1/3 in. to 1 in. with a step of 1/3 in. The experimental results show that iron targets tend to produce a factor of five less observed x-rays and gammas, with less energetic photoelectron frequency distributions, compared with DU and lead targets for the same beam intensity and target thicknesses. Additionally, the self-shielding effect causes the lead to yield more gammas than the DU considering the experimental observation point. For the setup used in this study, a charge per pulse in the range of 1–2.5 nC yields the best resolving capability between the DU and lead targets.

  15. Final Report on DTRA Basic Research Project #BRCALL08-Per3-C-2-0006 "High-Z Non-Equilibrium Physics and Bright X-ray Sources with New Laser Targets"

    Energy Technology Data Exchange (ETDEWEB)

    Colvin, Jeffrey D. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-06-01

    This project had two major goals. Final Goal: obtain spectrally resolved, absolutely calibrated x-ray emission data from uniquely uniform mm-scale near-critical-density high-Z plasmas not in local thermodynamic equilibrium (LTE) to benchmark modern detailed atomic physics models. Scientific significance: advance understanding of non-LTE atomic physics. Intermediate Goal: develop new nano-fabrication techniques to make suitable laser targets that form the required highly uniform non-LTE plasmas when illuminated by high-intensity laser light. Scientific significance: advance understanding of nano-science. The new knowledge will allow us to make x-ray sources that are bright at the photon energies of most interest for testing radiation hardening technologies, the spectral energy range where current x-ray sources are weak. All project goals were met.

  16. Dynamic nuclear polarization of irradiated target materials

    International Nuclear Information System (INIS)

    Seely, M.L.

    1982-01-01

    Polarized nucleon targets used in high energy physics experiments usually employ the method of dynamic nuclear polarization (DNP) to polarize the protons or deuterons in an alcohol. DNP requires the presence of paramagnetic centers, which are customarily provided by a chemical dopant. These chemically doped targets have a relatively low polarizable nucleon content and suffer from loss of polarization when subjected to high doses of ionizing radiation. If the paramagnetic centers formed when the target is irradiated can be used in the DNP process, it becomes possible to produce targets using materials which have a relatively high polarizable nucleon content, but which are not easily doped by chemical means. Furthermore, the polarization of such targets may be much more radiation resistant. Dynamic nuclear polarization in ammonia, deuterated ammonia, ammonium hydroxide, methylamine, borane ammonia, butonal, ethane and lithium borohydride has been studied. These studies were conducted at the Stanford Linear Accelerator Center using the Yale-SLAC polarized target system. Results indicate that the use of ammonia and deuterated ammonia as polarized target materials would make significant increases in polarized target performance possible

  17. WEBEXPIR: Windowless target electron beam experimental irradiation

    International Nuclear Information System (INIS)

    Dierckx, Marc; Schuurmans, Paul; Heyse, Jan; Rosseel, Kris; Tichelen, Katrien Van; Nactergal, Benoit; Vandeplassche, Dirk; Aoust, Thierry; Abs, Michel; Guertin, Arnaud; Buhour, Jean-Michel; Cadiou, Arnaud; Abderrahim, Hamid Ait

    2008-01-01

    The windowless target electron beam experimental irradiation (WEBEXPIR) program was set-up as part of the MYRRHA/XT-ADS R and D effort on the spallation target design to investigate the interaction of a proton beam with a liquid lead-bismuth eutectic (LBE) free surface. In particular, possible free surface distortion or shockwave effects in nominal conditions and during sudden beam on/off transient situations, as well as possible enhanced evaporation were assessed. An experiment was conceived at the IBA TT-1000 Rhodotron, where a 7 MeV electron beam was used to simulate the high power deposition at the MYRRHA/XT-ADS LBE free surface. The geometry and the LBE flow characteristics in the WEBEXPIR set-up were made as representative as possible of the actual situation in the MYRRHA/XT-ADS spallation target. Irradiation experiments were carried out at beam currents of up to 10 mA, corresponding to 40 times the nominal beam current necessary to reproduce the MYRRHA/XT-ADS conditions. Preliminary analyses show that the WEBEXPIR free surface flow was not disturbed by the interaction with the electron beam and that vacuum conditions stayed well within the design specifications

  18. Interfractional Target Variations for Partial Breast Irradiation

    International Nuclear Information System (INIS)

    Ahunbay, Ergun E.; Robbins, Jared; Christian, Robert; Godley, Andrew; White, Julia; Li, X. Allen

    2012-01-01

    Purpose: In this work, we quantify the interfractional variations in the shape of the clinical target volume (CTV) by analyzing the daily CT data acquired during CT-guided partial breast irradiation (PBI) and compare the effectiveness of various repositioning alignment strategies considered to account for the variations. Methods and Materials: The daily CT data for 13 breast cancer patients treated with PBI in either prone (10 patients) or supine (3 patients) with daily kV CT guidance using CT on Rails (CTVision, Siemens, Malvern, PA) were analyzed. For approximately 25 points on the surface of the CTV, deformation vectors were calculated by means of deformable image registration and verified by visual inspection. These were used to calculate the distances along surface normals (DSN), which directly related to the required margin expansions for each point. The DSN values were determined for seven alignment methods based on volumetric imaging and also two-dimensional projections (portal imaging). Results: The margin expansion necessary to cover 99% of all points for all days was 2.7 mm when utilizing the alignment method based on deformation field data (the best alignment method). The center-of-mass based alignment yielded slightly worse results (a margin of 4.0 mm), and shifts obtained by operator placement (7.9 mm), two-dimensional-based methods (7.0–10.1 mm), and skin marks (13.9 mm) required even larger margin expansions. Target shrinkage was evident for most days by the negative values of DSN. Even with the best alignment, the range of DSN values could be as high as 7 mm, resulting in a large amount of normal tissue irradiation, unless adaptive replanning is employed. Conclusion: The appropriate alignment method is important to minimize the margin requirement to cover the significant interfractional target deformations observed during PBI. The amount of normal tissue unnecessarily irradiated is still not insignificant, and can be minimized if adaptive

  19. Irradiation of target volumes with concave outlines

    International Nuclear Information System (INIS)

    De Neve, W.; Fortan, L.; Derycke, S.; Van Duyse, B.; DE Wagter, C.

    1995-01-01

    A heuristic planning procedure allowing to obtain a 3-dimensional conformal dose distribution for target volumes with concavities has been investigated. The procedure divides the planning problem into a number of sub-problems each solvable by known methods. By patching together the solutions to the sub-problems, a solution with a predictable dosimetric outcome can be obtained. The procedure can be applied to most 3-dimensional systems. The procedure is described and its applications to the irradiation of neoplasms are discussed. (A.S.)

  20. Irradiation of target volumes with concave outlines

    Energy Technology Data Exchange (ETDEWEB)

    De Neve, W; Fortan, L; Derycke, S; Van Duyse, B; DE Wagter, C [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde

    1995-12-01

    A heuristic planning procedure allowing to obtain a 3-dimensional conformal dose distribution for target volumes with concavities has been investigated. The procedure divides the planning problem into a number of sub-problems each solvable by known methods. By patching together the solutions to the sub-problems, a solution with a predictable dosimetric outcome can be obtained. The procedure can be applied to most 3-dimensional systems. The procedure is described and its applications to the irradiation of neoplasms are discussed. (A.S.).

  1. Automation in irradiating target systems for cyclotrons

    International Nuclear Information System (INIS)

    Araujo, Sumair G.; Sciani, Valdir; Almeida, Rosemeire S.

    2000-01-01

    Nowadays, two cyclotron are being operated at IPEN-CNEN/SP: one model CV-28, capable of accelerating p, d, 3 He 4 and α, with energies of 24, 14, 36 and 28 MeV, respectively, and beam currents up to 30 μA; the other one, model cyclone 30, accelerates protons with energy of 30 MeV and currents up to 350 μ A. Both have the objective of irradiating targets both for radioisotope production for use in Nuclear Medicine, such as 67 Ga, 201 Tl, 111 In, 123 I, 18 F, and general research. The development of irradiating systems completely automatized was the objective of this work, always aiming to reduce the radiation exposition dose to the workers and to increasing the reliability of use of these systems, because very high activities are expected in these processes. In the automation, a Programmable Logical Controller (PLC) was used connected to a feedback net, to manage all the variables involved in the irradiation processes. The program of the PLC was developed using Simatic Step Seven (S7), Software from Siemens, where all the steps are supervised in screens at a microcomputer. The assembling and sequence of leading were developed using the software from Unisoft, that keeps the operator informed about the work being carried out, at any time. (author)

  2. Muon radiography technology for detecting high-Z materials

    International Nuclear Information System (INIS)

    Ma Lingling; Wang Wenxin; Zhou Jianrong; Sun Shaohua; Liu Zuoye; Li Lu; Du Hongchuan; Zhang Xiaodong; Hu Bitao

    2010-01-01

    This paper studies the possibility of using the scattering of cosmic muons to identify threatening high-Z materials. Various scenarios of threat material detection are simulated with the Geant4 toolkit. PoCA (Point of Closest Approach) algorithm reconstructing muon track gives 3D radiography images of the target material. Z-discrimination capability, effects of the placement of high-Z materials, shielding materials inside the cargo, and spatial resolution of position sensitive detector for muon radiography are carefully studied. Our results show that a detector position resolution of 50 μm is good enough for shielded materials detection. (authors)

  3. Method for mounting laser fusion targets for irradiation

    Science.gov (United States)

    Fries, R. Jay; Farnum, Eugene H.; McCall, Gene H.

    1977-07-26

    Methods for preparing laser fusion targets of the ball-and-disk type are disclosed. Such targets are suitable for irradiation with one or two laser beams to produce the requisite uniform compression of the fuel material.

  4. Multi-MW accelerator target material properties under proton irradiation at Brookhaven National Laboratory linear isotope producer

    Science.gov (United States)

    Simos, N.; Ludewig, H.; Kirk, H.; Dooryhee, E.; Ghose, S.; Zhong, Z.; Zhong, H.; Makimura, S.; Yoshimura, K.; Bennett, J. R. J.; Kotsinas, G.; Kotsina, Z.; McDonald, K. T.

    2018-05-01

    The effects of proton beams irradiating materials considered for targets in high-power accelerator experiments have been studied using the Brookhaven National Laboratory's (BNL) 200 MeV proton linac. A wide array of materials and alloys covering a wide range of the atomic number (Z) are being scoped by the high-power accelerator community prompting the BNL studies to focus on materials representing each distinct range, i.e. low-Z, mid-Z and high-Z. The low range includes materials such as beryllium and graphite, the midrange alloys such as Ti-6Al-4V, gum metal and super-Invar and finally the high-Z range pure tungsten and tantalum. Of interest in assessing proton irradiation effects are (a) changes in physiomechanical properties which are important in maintaining high-power target functionality, (b) identification of possible limits of proton flux or fluence above which certain materials cease to maintain integrity, (c) the role of material operating temperature in inducing or maintaining radiation damage reversal, and (d) phase stability and microstructural changes. The paper presents excerpt results deduced from macroscopic and microscopic post-irradiation evaluation (PIE) following several irradiation campaigns conducted at the BNL 200 MeV linac and specifically at the isotope producer beam-line/target station. The microscopic PIE relied on high energy x-ray diffraction at the BNL NSLS X17B1 and NSLS II XPD beam lines. The studies reveal the dramatic effects of irradiation on phase stability in several of the materials, changes in physical properties and ductility loss as well as thermally induced radiation damage reversal in graphite and alloys such as super-Invar.

  5. Irradiated target cooling using circular air jet

    International Nuclear Information System (INIS)

    Selvaraj, P.; Natesan, K.; Velusamy, K.; Baskaran, V.; Sundararajan, T.

    2015-01-01

    To study the effect of irradiation on materials, sample coupons are irradiated in cyclotron facilities. During the irradiation process, these samples produce significant heat. This heat needs to be continuously removed from the samples in order to avoid melting of the samples as well as to keep the samples at a particular temperature during irradiation. The area available for heat transfer is limited due to the small size of the samples. To increase the heat transfer rate, jet cooling is used as it provides large heat transfer co-efficient. To understand the heat transfer characteristics of jet cooling under these conditions, experiments have been carried out. Electric Joule heating is adopted to simulate irradiation heat in stainless steel samples. An array of circular nozzles is used to create air jet. From the study the values of the parameters correspond to the maximum heat removal rate are found out. The results are also compared with an empirical correlation from the literature. (author)

  6. The BLAIRR Irradiation Facility Hybrid Spallation Target Optimization

    Energy Technology Data Exchange (ETDEWEB)

    Simos N.; Hanson A.; Brown, D.; Elbakhshawn, M.

    2016-04-11

    BLAIRR STUDY STATUS OVERVIEW Beamline Complex Evaluation/Assessment and Adaptation to the Goals Facility Radiological Constraints ? Large scale analyses of conventional facility and integrated shield (concrete, soil)Target Optimization and Design: Beam-target interaction optimization Hadronic interaction and energy deposition limitations Single phase and Hybrid target concepts Irradiation Damage Thermo-mechanical considerations Spallation neutron fluence optimization for (a) fast neutron irradiation damage (b) moderator/reflector studies, (c) NTOF potential and optimization (d) mono-energetic neutron beam

  7. L-shell emission from high-Z solid targets by intense (10{sup 19}W/cm{sup 2}) irradiation with a 248nm laser

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, T. R.; Borisov, A. B.; Boyer, K.; Schroeder, W. A.; Santoro, J.; Van Tassle, A. J.; Rhodes, C. K.; Luk, T. S.; Cameron, S.; Longworth, J. W.; McPherson, A.

    1999-11-22

    Efficient (1.2% yield) multikilovolt x-ray emission from Ba(L) (2.4--2.8{angstrom}) and Gd(L) (1.7--2.1{angstrom}) is produced by ultraviolet (248nm) laser-excited BaF{sub 2} and Gd solids. The high efficiency is attributed to an inner shell-selective collisional electron ejection.

  8. Recovery of uranium from an irradiated solid target after removal of molybdenum-99 produced from the irradiated target

    Science.gov (United States)

    Reilly, Sean Douglas; May, Iain; Copping, Roy; Dale, Gregory Edward

    2017-10-17

    A process for minimizing waste and maximizing utilization of uranium involves recovering uranium from an irradiated solid target after separating the medical isotope product, molybdenum-99, produced from the irradiated target. The process includes irradiating a solid target comprising uranium to produce fission products comprising molybdenum-99, and thereafter dissolving the target and conditioning the solution to prepare an aqueous nitric acid solution containing irradiated uranium. The acidic solution is then contacted with a solid sorbent whereby molybdenum-99 remains adsorbed to the sorbent for subsequent recovery. The uranium passes through the sorbent. The concentrations of acid and uranium are then adjusted to concentrations suitable for crystallization of uranyl nitrate hydrates. After inducing the crystallization, the uranyl nitrate hydrates are separated from a supernatant. The process results in the purification of uranyl nitrate hydrates from fission products and other contaminants. The uranium is therefore available for reuse, storage, or disposal.

  9. High-Z organic-scintillation solution

    International Nuclear Information System (INIS)

    Berlman, I.B.; Fluornoy, J.M.; Ashford, C.B.; Lyons, P.B.

    1983-01-01

    In the present experiment, an attempt is made to raise the average Z of a scintillation solution with as little attendant quenching as possible. Since high-Z atoms quench by means of a close encounter, such encounters are minimized by the use of alkyl groups substituted on the solvent, solute, and heavy atoms. The aromatic compound 1,2,4-trimethylbenzene (pseudocumene) is used as the solvent; 4,4''-di(5-tridecyl)-p-terphenyl (SC-180) as the solute; and tetrabutyltin as the high-Z material. To establish the validity of our ideas, various experiments have been performed with less protected solvents, and heavy atoms. These include benzene, toluene, p-terphenyl, bromobutane, and bromobenzene

  10. Preliminary Beam Irradiation Test for RI Production Targets at KOMAC

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sang Pil; Kwon, Hyeok Jung; Kim, Han Sung; Cho, Yong Sub; Seol, Kyung Tae; Song, Young Gi; Kim, Dae Il; Jung, Myung Hwan; Kim, Kye Ryung; Min, Yi Sub [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The new beamline and target irradiation facility has been constructed for the production of therapeutic radio-isotope. Sr-82 and Cu-67 were selected as the target isotope in this facility, they are promising isotope for the PET imaging and cancer therapy. For the facility commissioning, the irradiation test for the prototype-target was conducted to confirm the feasibility of radio-isotope production, the proto-type targets are made of RbCl pellet and the natural Zn metal for Sr-82 and Cu-67 production respectively, In this paper, an introduction to the RI production targetry system and the results of the preliminary beam irradiation test are discussed. the low-flux beam irradiation tests for proto-type RI target have been conducted. As a result of the beam irradiation tests, we could obtain the evidence of Sr-82 and Cu-67 production, have confirmed the feasibility of Sr-82 and Cu-67 production at KOMAC RI production facility.

  11. Preliminary Beam Irradiation Test for RI Production Targets at KOMAC

    International Nuclear Information System (INIS)

    Yoon, Sang Pil; Kwon, Hyeok Jung; Kim, Han Sung; Cho, Yong Sub; Seol, Kyung Tae; Song, Young Gi; Kim, Dae Il; Jung, Myung Hwan; Kim, Kye Ryung; Min, Yi Sub

    2016-01-01

    The new beamline and target irradiation facility has been constructed for the production of therapeutic radio-isotope. Sr-82 and Cu-67 were selected as the target isotope in this facility, they are promising isotope for the PET imaging and cancer therapy. For the facility commissioning, the irradiation test for the prototype-target was conducted to confirm the feasibility of radio-isotope production, the proto-type targets are made of RbCl pellet and the natural Zn metal for Sr-82 and Cu-67 production respectively, In this paper, an introduction to the RI production targetry system and the results of the preliminary beam irradiation test are discussed. the low-flux beam irradiation tests for proto-type RI target have been conducted. As a result of the beam irradiation tests, we could obtain the evidence of Sr-82 and Cu-67 production, have confirmed the feasibility of Sr-82 and Cu-67 production at KOMAC RI production facility

  12. On corotating high-z HI

    International Nuclear Information System (INIS)

    Lockman, F.J.

    1983-01-01

    There is evidence in surveys of HI in the inner Galaxy for gas more than 500 pc from the plane that shares the rotation of material in the plane. The percentage of HI with mod(z) > 500 pc at the subcentral points rises approximately montonically from less than 2% at R 15% near the solar neighborhood. Some cloudy structure is observed. Some of the high-z gas has a larger velocity dispersion than the HI confined more closely to the plane. (Auth.)

  13. Saha's ionization equation for high Z elements

    International Nuclear Information System (INIS)

    Godwal, B.K.; Sikka, S.K.

    1977-01-01

    Saha's ionization equation has been solved for high Z elements with the aim of providing input for opacity calculations. Results are presented for two elements, tungsten and uranium. The ionization potentials have been evaluated using the simple Bhor's formula with suitable effective charges for ions. The reliability of the free electron density, ion concentrations, etc., obtained from the Saha's equation solutions has been checked by comparing the P and E computed from them with those given by the Thomas-Fermi-Dirac equation of state. The agreement between the two is good from temperatures above 0.2 keV. (author)

  14. Computational Modeling of Ablation on an Irradiated Target

    Science.gov (United States)

    Mehmedagic, Igbal; Thangam, Siva

    2017-11-01

    Computational modeling of pulsed nanosecond laser interaction with an irradiated metallic target is presented. The model formulation involves ablation of the metallic target irradiated by pulsed high intensity laser at normal atmospheric conditions. Computational findings based on effective representation and prediction of the heat transfer, melting and vaporization of the targeting material as well as plume formation and expansion are presented along with its relevance for the development of protective shields. In this context, the available results for a representative irradiation from 1064 nm laser pulse is used to analyze various ablation mechanisms, variable thermo-physical and optical properties, plume expansion and surface geometry. Funded in part by U. S. Army ARDEC, Picatinny Arsenal, NJ.

  15. Post-Irradiation Examination of Array Targets - Part I

    Energy Technology Data Exchange (ETDEWEB)

    Icenhour, A.S.

    2004-01-23

    During FY 2001, two arrays, each containing seven neptunium-loaded targets, were irradiated at the Advanced Test Reactor in Idaho to examine the influence of multi-target self-shielding on {sup 236}Pu content and to evaluate fission product release data. One array consisted of seven targets that contained 10 vol% NpO{sub 2} pellets, while the other array consisted of seven targets that contained 20 vol % NpO{sub 2} pellets. The arrays were located in the same irradiation facility but were axially separated to minimize the influence of one array on the other. Each target also contained a dosimeter package, which consisted of a small NpO{sub 2} wire that was inside a vanadium container. After completion of irradiation and shipment back to the Oak Ridge National Laboratory, nine of the targets (four from the 10 vol% array and five from the 20 vol% array) were punctured for pressure measurement and measurement of {sup 85}Kr. These nine targets and the associated dosimeters were then chemically processed to measure the residual neptunium, total plutonium production, {sup 238}Pu production, and {sup 236}Pu concentration at discharge. The amount and isotopic composition of fission products were also measured. This report provides the results of the processing and analysis of the nine targets.

  16. Diffuse scattering from laser-irradiated plane targets

    International Nuclear Information System (INIS)

    Kessel, C.G.M. van; Olsen, J.N.; Sachsenmaier, P.; Sigel, R.; Eidmann, K.; Godwin, R.P.

    1976-11-01

    Optical calorimetry of the laser radiation scattered from plane targets irradiated by 0.3 Joule/30 ps Nd-laser pulses with intensities up to 10 16 W cm -2 has been performed with an emphasis on diffuse scattering. Diffuse scattering outside the solid angle of the focusing lens is found to be a major reflection loss from the target. A fraction of 0.3 to 0.5 of the incident pulse energy was absorbed in the target with only a very weak dependence on pulse energy and target material. (orig.) [de

  17. High-vacuum chamber for the irradiation of targets

    International Nuclear Information System (INIS)

    Krimmel, E.; Dullnig, H.

    1975-01-01

    The high vacuum chamber for irradiating targets with X-rays, electron or ion beams is connected to a magazine storage vessel for the targets through a loading duct which can be evacuated. This duct is traversed by a carriage transporting a magazine to the irradiation position. The duct can be closed by a closing valve. Inside the chamber there is a grip attached to a swivel arm which takes a frame with a target from the magazine, or vice versa, and moves it into the irradiation position. This means that the chamber must always be kept at a constant internal pressure. The swiveling shaft for the swivel arm and the transport pinion of the carriage in addition are magnetically coupled to drive shafts located outside the chamber, which obviates the need for any seals. The grip may also deposit the frame on a goniometer, which allows the target to be aligned in the irradiation position. In addition, the measuring probes used to record the amount of reflected radiation are installed in the chamber under electrically insulated conditions relative to the chamber. (DG/RF) [de

  18. Petawatt laser and target irradiation system at LLNL

    International Nuclear Information System (INIS)

    Pennington, D.M.; Perry, M.D.; Britten, J.A.; Brown, C.G.; Herman, S.; Homer, J.; Miller, J.L.; Stuart, B.C.; Tietbohl, G.; Van Lue, J.; Yanovsky, V.

    1997-01-01

    In May, 1996, we demonstrated the production over a petawatt of peak power in the Nova/Petawatt Laser Facility, generating 620 J in ∼ 430 fs. Results of the first focused irradiance tests, and recent deployment of a novel targeting system will be presented

  19. Recovery of hafnium radioisotopes from a proton irradiated tantalum target

    International Nuclear Information System (INIS)

    Taylor, W.A.; Garcia, J.G.; Hamilton, V.T.; Heaton, R.C.; Jamriska, D.J.; Ott, M.A.; Philips, D.R.; Radzinski, S.D.

    1998-01-01

    The 178m2 Hf nucleus, with its long half-life (31 y) and high-spin isomeric state (16 + ) is desired for new and exotic nuclear physics studies. The Los Alamos Radioisotope Program irradiated a kilogram of natural tantalum at the Los Alamos Meson Physics Facility in early 1981. After fifteen years of decay, this target was ideal for the recovery of 178m2 Hf. There was more than a millicurie of 178m2 Hf produced during this irradiation and there has been a sufficient period of time for most of the other hafnium radioisotopes to decayed away. Traditionally, separation techniques for recovering hafnium isotopes from tantalum targets employ solvent extractions with reagents that are considered hazardous. These techniques are no longer condoned because they generate a mixed-waste (radioactive and hazardous components) that can not be treated for disposal. In this paper we describe a new and unique procedure for the recovery of hafnium radioisotopes from a highly radioactive, proton irradiated, tantalum target using reagents that do not contribute a hazardous waste component. (author)

  20. Analytical dose modeling for preclinical proton irradiation of millimetric targets.

    Science.gov (United States)

    Vanstalle, Marie; Constanzo, Julie; Karakaya, Yusuf; Finck, Christian; Rousseau, Marc; Brasse, David

    2018-01-01

    Due to the considerable development of proton radiotherapy, several proton platforms have emerged to irradiate small animals in order to study the biological effectiveness of proton radiation. A dedicated analytical treatment planning tool was developed in this study to accurately calculate the delivered dose given the specific constraints imposed by the small dimensions of the irradiated areas. The treatment planning system (TPS) developed in this study is based on an analytical formulation of the Bragg peak and uses experimental range values of protons. The method was validated after comparison with experimental data from the literature and then compared to Monte Carlo simulations conducted using Geant4. Three examples of treatment planning, performed with phantoms made of water targets and bone-slab insert, were generated with the analytical formulation and Geant4. Each treatment planning was evaluated using dose-volume histograms and gamma index maps. We demonstrate the value of the analytical function for mouse irradiation, which requires a targeting accuracy of 0.1 mm. Using the appropriate database, the analytical modeling limits the errors caused by misestimating the stopping power. For example, 99% of a 1-mm tumor irradiated with a 24-MeV beam receives the prescribed dose. The analytical dose deviations from the prescribed dose remain within the dose tolerances stated by report 62 of the International Commission on Radiation Units and Measurements for all tested configurations. In addition, the gamma index maps show that the highly constrained targeting accuracy of 0.1 mm for mouse irradiation leads to a significant disagreement between Geant4 and the reference. This simulated treatment planning is nevertheless compatible with a targeting accuracy exceeding 0.2 mm, corresponding to rat and rabbit irradiations. Good dose accuracy for millimetric tumors is achieved with the analytical calculation used in this work. These volume sizes are typical in mouse

  1. Methods of thallium-201 preparation from proton irradiated thallium targets

    International Nuclear Information System (INIS)

    Kozlova, M.D.; Sevast'yanova, A.S.; Malinin, A.B.; Kurenkov, N.V.

    1989-01-01

    Two methods of thallium-201 preparation from Tl-targets irradiated by protons: oxidation-extraction (1) and extraction (2) - are developed. At first radioactive lead is separated from the target material - thallium macroquantities during ∼32 hours, then thallium-201 was separated from residual activity of lead radioisotopes and transformed it into the necessary chemical formula. The 1st and 2nd methods differ from each other by the 1st stage of target retreatment; only extraction was used to separate radioactive lead in the 2nd method. The target was solved in H 2 SO 4 . The 1st method permits to separate thallium-201 with chemical yield not less than 90 %, the 2nd one - higher than 95 %. Volumetric activity of thallium-201 prepared is more than 55 MBq/ml. 5 refs

  2. Chemical recovery of palladium-103 from irradiated silver target

    International Nuclear Information System (INIS)

    Lapshina, E.V.; Kokhanyuk, V.M.; Zhuikov, B.L.; Myasoedova, G.V.; Zakhartchenko, E.A.; Phillips, D.R.; Jamriska, D.J.

    2003-01-01

    The goal of this work is to develop an extraction method of no-carrier-added palladium-103 from silver. Metallic silver targets may be irradiated by protons with energy of 60-200 MeV or more to generate palladium-103 simultaneously with other radioactive isotopes of rhodium, ruthenium, technetium, palladium and silver. According to the dependence experimental production yield of Pd-103 and isotopes of other elements in thick silver target vs. Proton energy the most suitable energy for maximum yield of Pd-103 and minimum yield of other elements is from about 100 to about 140 MeV. Activity of radionuclides produced in silver target depends from many factors (target thickness, irradiation time, etc.). Two methods of Pd-103 recovering from irradiated silver target are considered in this work: (1) Silver target is dissolved in nitric acid followed by silver precipitation in the form of silver chloride by addition of HCl. The solution containing Pd, Rh and other radionuclides is passed through the layer of fibrous sorbent POLYORGS-15n. Then the sorbent is washed and Pd is desorbed by hot 12 M hydrochloric acid; (2) Silver target is dissolved in nitric acid followed by passing of the obtained solution (2 M HNO 3 ) through a disk set of complex forming sorbent POLYORGS-33n. Under these conditions palladium is sorbed by the sorbent while silver, rhodium, ruthenium and technetium are passed through the sorbent. Then the sorbent is washed with 2M nitric acid, and Pd is desorbed by 12 M hydrochloric acid. Extraction of palladium is occurred during the formation of palladium complex with a chelate sorbent specific to palladium in acidic solutions. Such a sorbent makes possible separation of palladium from accompanying radionuclides such as rhodium, ruthenium and technetium. The polymeric complex-forming sorbent of fibrous structure with the groups of 3(5)-methylpyrazole (POLYORGS-15) is used. The distinctive feature of the sorbents in the form of fibrous 'filled' material is

  3. Analysis of Mo99 production irradiating 20% U targets

    International Nuclear Information System (INIS)

    Calabrese, C. Ruben; Grant, Carlos R.; Marajofsky, Andres; Parkansky, David G.

    1999-01-01

    At present time, the National Atomic Energy Commission is producing about 800 Ci of Mo99 per week irradiating 90% enriched uranium-aluminum alloy plate targets in the RA-3 reactor, a 5 MW. Mtr type one. In order to change to 20% enriched uranium, and to increase the production to about 3000 Ci per week some configurations were studied with rod and plate geometry with uranium (20% enriched) -aluminum targets. The first case was the irradiation of a plate target element in the normal reactor configuration. Results showed a good efficiency, but both reactivity value and power density were too high. An element with rods was also analyzed, but results showed a poor efficiency, too much aluminum involved in the process, although a low reactivity and an acceptable rod power density. Finally, a solution consisting of plate elements with a Zircaloy cladding was adopted, which has shown not only a good efficiency, but it is also acceptable from the viewpoint of safety, heat transference criteria and feasibility

  4. Cosmological Results from High-z Supernovae

    Science.gov (United States)

    Tonry, John L.; Schmidt, Brian P.; Barris, Brian; Candia, Pablo; Challis, Peter; Clocchiatti, Alejandro; Coil, Alison L.; Filippenko, Alexei V.; Garnavich, Peter; Hogan, Craig; Holland, Stephen T.; Jha, Saurabh; Kirshner, Robert P.; Krisciunas, Kevin; Leibundgut, Bruno; Li, Weidong; Matheson, Thomas; Phillips, Mark M.; Riess, Adam G.; Schommer, Robert; Smith, R. Chris; Sollerman, Jesper; Spyromilio, Jason; Stubbs, Christopher W.; Suntzeff, Nicholas B.

    2003-09-01

    The High-z Supernova Search Team has discovered and observed eight new supernovae in the redshift interval z=0.3-1.2. These independent observations, analyzed by similar but distinct methods, confirm the results of Riess and Perlmutter and coworkers that supernova luminosity distances imply an accelerating universe. More importantly, they extend the redshift range of consistently observed Type Ia supernovae (SNe Ia) to z~1, where the signature of cosmological effects has the opposite sign of some plausible systematic effects. Consequently, these measurements not only provide another quantitative confirmation of the importance of dark energy, but also constitute a powerful qualitative test for the cosmological origin of cosmic acceleration. We find a rate for SN Ia of (1.4+/-0.5)×10-4h3Mpc-3yr-1 at a mean redshift of 0.5. We present distances and host extinctions for 230 SN Ia. These place the following constraints on cosmological quantities: if the equation of state parameter of the dark energy is w=-1, then H0t0=0.96+/-0.04, and ΩΛ-1.4ΩM=0.35+/-0.14. Including the constraint of a flat universe, we find ΩM=0.28+/-0.05, independent of any large-scale structure measurements. Adopting a prior based on the Two Degree Field (2dF) Redshift Survey constraint on ΩM and assuming a flat universe, we find that the equation of state parameter of the dark energy lies in the range -1.48-1, we obtain wInstitute, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc., under NASA contract NAS 5-26555. This research is primarily associated with proposal GO-8177, but also uses and reports results from proposals GO-7505, 7588, 8641, and 9118. Based in part on observations taken with the Canada-France-Hawaii Telescope, operated by the National Research Council of Canada, le Centre National de la Recherche Scientifique de France, and the University of Hawaii. CTIO: Based in part on observations taken at the Cerro Tololo Inter

  5. Chemical recovery of a palladium-103 from irradiated silver target

    International Nuclear Information System (INIS)

    Lapshina, E.V.; Kokhanyuk, V.M.; Zhuikov, B.L.; Myasoedova, G.V.; Zakhartchenko, E.A.; Phillips, D.R.; Jamriska, D.J.

    2003-01-01

    The goal of this work is to develop an extraction method of no-carrier-added palladium-103 from silver. Metallic silver targets were irradiated by protons with the energy of 60-140 MeV to generate palladium-103. Other radioactive isotopes of rhodium, ruthenium, technetium, palladium and silver are also formed at the same time. Two methods of Pd-103 recovering from irradiated silver target are considered. The first one includes the dissolving of the irradiated silver target in nitric acid followed by adding of hydrochloric acid to the solution. Palladium with rhodium, ruthenium and technetium completely remained in solution while silver was precipitated in the form of silver chloride. Extraction of palladium from the obtained solution was provided by the formation of palladium complex with a chelate sorbent which is specific to palladium in acidic solutions. The sorbent makes it possible to separate palladium from admixtures of rhodium, ruthenium and technetium isotopes. The polymeric complex-forming sorbent of fibrous structure with the groups of 3 (5) - methylpyrazole (POLYORGS-15n) is used. An other possible method has been also studied. It includes again dissolving of metallic silver in nitric acid, but does not need silver chloride precipitation. Silver may be sorbed by the complex-forming sorbents, but its sorption is very sensitive to acid concentration. Chelate sorbents of fibrous structure with the groups of amidoxime and hydrazidine (POLYORGS-33n) have been successfully used in our experiments. A high efficiency of palladium extraction by POLYORGS-33n from 2-4 M nitric acid solutions was achieved. Concentrated hydrochloric acid (without heating) was used for palladium desorption with higher yield than in the first method. (authors)

  6. Thermal transport measurements of uv laser irradiated spherical targets

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; Delettrez, J.; Henke, B.L.; Richardson, M.C.

    1985-01-01

    New measurements are presented of thermal transport in spherical geometry using time-resolved x-ray spectroscopy. We determine the time dependence of the mass ablation rate m(dot) by following the progress of the ablation surface through thin layers of material embedded at various depths below the surface of the target. These measurements made with 6 and 12 uv (351 nm) beams from OMEGA are compared to previous thermal transport data and are in qualitative agreement with detailed LILAC hydrodynamic code simulations which predict a sharp decrease in m(dot) after the peak of the laser pulse. Non-uniform laser irradiation of the target results in the anomalously high values of m(dot) measured in these experiments

  7. Review of high Z materials for PSI applications

    International Nuclear Information System (INIS)

    Tanabe, Tetsuo; Noda, Nobuaki; Nakamura, Hiroo.

    1992-06-01

    Application of carbon based low Z materials to PFM has significantly improved plasma parameters in large tokamaks. There are, however, serious concerns of erosion, neutron damage etc. for application of low Z materials in future D - T burning machine. To apply high Z metals to PFM, there are several issues to be solved; high Z impurity production by sputtering, their accumulation in plasma center, and high radiation loss. Because of these concerns high Z metals are not widely employed nor planned to be used in the present large tokamaks. Since our efforts have been concentrated to optimize the low Z materials, little systematic investigations for high Z materials in tokamak have been done, lacking data base especially those concerning the impacts on plasma core. In order to employ high Z material as PFM near future, material properties related to impurity production and hydrogen recycling are reviewed and discussed what is important and what shall be done. (author) 109 refs

  8. Interaction of intense femtosecond laser pulses with high-Z solids

    International Nuclear Information System (INIS)

    Zhidkov, A.; Sasaki, Akira; Utsumi, Takayuki; Fukumoto, Ichirou; Tajima, Toshiki; Yoshida, Masatake; Kondo, Kenichi

    2000-01-01

    A plasma irradiated by an intense very short pulse laser can be an ultimate high brightness source of incoherent inner-shell X-ray emission of 1-30 keV. The recently developed 100 TW, 20 fs laser facility in JAERI can make considerable enhancement here. To show this a hybrid model combining hydrodynamics and collisional particle-in-cell simulations is applied. Effect of laser prepulse on the interaction of an intense s-polarized femtosecond, ∼20/40 fs, laser pulse with high-Z solid targets is studied. A new absorption mechanism originating from the interaction of the laser pulse with plasma waves excited by the relativistic component of the Lorentz force is found to increase the absorption rate over 30% even for a very short laser pulse. The obtained hot electron temperature exceeds 0.5-1 MeV at optimal conditions for absorption. Results of the simulation for lower laser pulse intensities are in good agreement with the experimental measurements of the hot electron energy distribution. (author)

  9. Photo-neutron yields from thin and thick targets irradiated by 2.0 GeV electrons

    International Nuclear Information System (INIS)

    Hee-Seock, Lee; Syuichi, Ban; Toshiya, Sanami; Kazutoshi, Takahashi; Tatsuhiko, Sato; Kazuo, Shin

    2005-01-01

    The photo-neutron yields from thin and thick targets irradiated by high energy electrons were studied. The photo-neutron spectra at 90 deg C relative to the incident 2.0 GeV electrons were measured by the pulsed beam time-of-flight technique using the Pilot-U plastic scintillator and the NE213 liquid scintillator with 2 inches in length and 2 inches in diameter. Targets, from low-Z element (carbon) to high-Z element (bismuth) and with thin (0.5 Xo) and thick (10 Xo) thickness, were used in this study. The differential photo-neutron yields between 2 MeV (mainly 8 MeV) and 400 MeV were obtained. The systematics was studied to make empirical yield terms for shielding application. Recently, the study of the angular distributed yields was conducted at two other observing angles, 48 deg C and 140 deg C. The photo-neutron yields between 8 MeV and 250 MeV were obtained for thick targets. The experimental data were compared with results calculated using the EGS4+PICA3 or the MCNPX 2.5d code. (authors)

  10. Communicating the non-targeted effects of radiation from irradiated to non-irradiated cells

    International Nuclear Information System (INIS)

    Laiakis, E.C.; Morgan, W.F.

    2005-01-01

    For many years, the central dogma in radiobiology has been that energy deposited in the cell nucleus is responsible for the biological effects associated with radiation exposure. However, non-targeted and delayed effects of radiation have shifted this belief. The studies of radiation-induced genomic instability, the bystander and abscopal effects, clastogenic factors, and the Death Inducing Effect have dominated the interest of the radiobiology field of late. The passing of signals from irradiated to non-irradiated cells can be accomplished through cell-to-cell gap junction communication or secretion of molecules, which in turn can elicit a response through activation of signal transduction pathways. Proposed mediators of this phenotype include proteins involved with inflammation. Given their size and connection with oxidative stress, cytokines are an attractive candidate as mediators of the induction of the non-targeted effects of radiation. Here we review the evidence for a possible connection between these delayed non-targeted effects of radiation and the cytokine cascades associated with inflammation. (author)

  11. Optical emission from Al target irradiated by FLASH

    International Nuclear Information System (INIS)

    Stránský, M; Rohlena, K

    2014-01-01

    The following text touches on some peculiarities in optical emission spectroscopy results from experiments on the free-electron laser FLASH [1, 2]. Aluminum targets were irradiated with 13.5 nm ∼ 25 fs pulses at intensities of 10 13 and 10 16 W/cm 2 (20 and 1 μm foci). Surprisingly, only neutral atom lines for the case with wider focus and traces of ion lines in the tighter focus case were observed with the optical emission spectroscopy (200–600 nm range), [2]. The motivating idea behind this work is the suggestion in [1] by Zastrau that the optical spectrometer sees only emissions from a cold expanding lower-density (< 10 22 cm −3 ) plasma plume. In this contribution the notion of UV range screening is analyzed in detail.

  12. Experimental Study of High-Z Gas Buffers in Gas-Filled ICF Engines

    Energy Technology Data Exchange (ETDEWEB)

    Rhodes, M A; Kane, J; Loosmore, G; DeMuth, J; Latkowski, J

    2010-12-03

    ICF power plants, such as the LIFE scheme at LLNL, may employ a high-Z, target-chamber gas-fill to moderate the first-wall heat-pulse due to x-rays and energetic ions released during target detonation. To reduce the uncertainties of cooling and beam/target propagation through such gas-filled chambers, we present a pulsed plasma source producing 2-5 eV plasma comprised of high-Z gases. We use a 5-kJ, 100-ns theta discharge for high peak plasma-heating-power, an electrode-less discharge for minimizing impurities, and unobstructed axial access for diagnostics and beam (and/or target) propagation studies. We will report on the plasma source requirements, design process, and the system design.

  13. Experimental benchmark for an improved simulation of absolute soft-X-ray emission from polystyrene targets irradiated with the Nike laser

    International Nuclear Information System (INIS)

    Weaver, J.L.; Colombant, D.G.; Mostovych, A.N.; Busquet, M.; Feldman, U.; Klapisch, M.; Seely, J.F.; Brown, C.; Holland, G.

    2005-01-01

    Absolutely calibrated, time-resolved spectral intensity measurements of soft-x-ray emission (hν∼0.1-1.0 keV) from laser-irradiated polystyrene targets are compared to radiation-hydrodynamic simulations that include our new postprocessor, Virtual Spectro. This new capability allows a unified, detailed treatment of atomic physics and radiative transfer in nonlocal thermodynamic equilibrium conditions for simple spectra from low-Z materials as well as complex spectra from high-Z materials. The excellent agreement (within a factor of ∼1.5) demonstrates the powerful predictive capability of the codes for the complex conditions in the ablating plasma. A comparison to data with high spectral resolution (E/δE∼1000) emphasizes the importance of including radiation coupling in the quantitative simulation of emission spectra

  14. Experimental benchmark for an improved simulation of absolute soft-x-ray emission from polystyrene targets irradiated with the Nike laser.

    Science.gov (United States)

    Weaver, J L; Busquet, M; Colombant, D G; Mostovych, A N; Feldman, U; Klapisch, M; Seely, J F; Brown, C; Holland, G

    2005-02-04

    Absolutely calibrated, time-resolved spectral intensity measurements of soft-x-ray emission (hnu approximately 0.1-1.0 keV) from laser-irradiated polystyrene targets are compared to radiation-hydrodynamic simulations that include our new postprocessor, Virtual Spectro. This new capability allows a unified, detailed treatment of atomic physics and radiative transfer in nonlocal thermodynamic equilibrium conditions for simple spectra from low-Z materials as well as complex spectra from high-Z materials. The excellent agreement (within a factor of approximately 1.5) demonstrates the powerful predictive capability of the codes for the complex conditions in the ablating plasma. A comparison to data with high spectral resolution (E/deltaE approximately 1000) emphasizes the importance of including radiation coupling in the quantitative simulation of emission spectra.

  15. Characteristics of extreme ultraviolet emission from high-Z plasmas

    International Nuclear Information System (INIS)

    Ohashi, H.; Higashiguchi, T.; Suzuki, Y.; Kawasaki, M.; Suzuki, C.; Tomita, K.; Nishikino, M.; Fujioka, S.; Endo, A.; Li, B.; Otsuka, T.; Dunne, P.; O'Sullivan, G.

    2016-01-01

    We demonstrate the extreme ultraviolet (EUV) and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6.x nm and the water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on high-Z plasma UTA source, coupled to multilayer mirror optics. (paper)

  16. Characteristics of extreme ultraviolet emission from high-Z plasmas

    Science.gov (United States)

    Ohashi, H.; Higashiguchi, T.; Suzuki, Y.; Kawasaki, M.; Suzuki, C.; Tomita, K.; Nishikino, M.; Fujioka, S.; Endo, A.; Li, B.; Otsuka, T.; Dunne, P.; O'Sullivan, G.

    2016-03-01

    We demonstrate the extreme ultraviolet (EUV) and soft x-ray sources in the 2 to 7 nm spectral region related to the beyond EUV (BEUV) question at 6.x nm and the water window source based on laser-produced high-Z plasmas. Resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs), extending below the carbon K edge (4.37 nm). An outline of a microscope design for single-shot live cell imaging is proposed based on high-Z plasma UTA source, coupled to multilayer mirror optics.

  17. X-ray imaging of targets irradiated by the Nike KrF laser

    International Nuclear Information System (INIS)

    Brown, C.; Seely, J.; Feldman, U.; Obenschain, S.; Bodner, S.; Pawley, C.; Gerber, K.; Serlin, V.; Sethian, J.; Aglitskiy, Y.; Lehecka, T.; Holland, G.

    1997-01-01

    Foil targets irradiated by the Naval Research Laboratory Nike KrF laser were imaged in the x-ray region with two-dimensional spatial resolution in the 2 endash 10 μm range. The images revealed the smoothness of the emission from target and backlighter foils, the acceleration of the target foils, and the growth of Rayleigh endash Taylor instabilities that were seeded by patterns on the irradiated sides of CH foils

  18. Study on irradiation conditions of producing 153Sm with natural abundance samarium target

    International Nuclear Information System (INIS)

    Du Jin; Jin Xiaohai; Bai Hongsheng; Liu Yuemin; Chen Daming; Wang Fan

    1998-01-01

    Irradiation conditions of natural abundance 152 Sm targets in different forms are studied in the heavy water reactor and the light water swimming pool reactor at the China Institute of Atomic Energy. The result shows that the specific activity of 153 Sm in liquid form target irradiated in the light water swimming pool reactor is two times greater than that in solid form target. The radionuclide purity of 153 Sm is more than 99%, which can meet the needs of clinical application

  19. Manual for target thickness measurement by alpha particle irradiation

    International Nuclear Information System (INIS)

    Dias, J.F.; Martins, M.N.

    1990-04-01

    A system is described for thin-target thickness measurement through the alpha particle energy loss when them traverse the target. It is also described the program used in the analysis of the target thickness. (L.C.) [pt

  20. Accumulation of the radionuclides in a target irradiated in the reactor of tajoura nuclear research center

    International Nuclear Information System (INIS)

    Abdunnobi, A.R.; Arebi, B.

    1998-01-01

    One of the main stages of radionuclides production in reactor is the distinguishing of a regime on target irradiation in order to acquire the sufficient activity and the purity of radioisotope required. The authors have derived formula for calculating radionuclidic accumulation on a target irradiated in the reactor operating 10 hours per day, 4 days a week during 4 weeks. The results of I-131 and other radionuclide accumulation are illustrated by a tellurium target irradiation in the reactor operating continuously or with interruptions

  1. Irradiation uniformity of spherical targets by multiple uv beams from OMEGA

    International Nuclear Information System (INIS)

    Beich, W.; Dunn, M.; Hutchison, R.

    1984-01-01

    Direct-drive laser fusion demands extremely high levels of irradiation uniformity to ensure uniform compression of spherical targets. The assessment of illumination uniformity of targets irradiated by multiple beams from the OMEGA facility is made with the aid of multiple beams spherical superposition codes, which take into account ray tracing and absorption and a detailed knowledge of the intensity distribution of each beam in the target plane. In this report, recent estimates of the irradiation uniformity achieved with 6 and 12 uv beams of OMEGA will be compared with previous measurements in the IR, and predictions will be made for the uv illumination uniformity achievable with 24 beams of OMEGA

  2. The alpha-particle irradiator set up at the ISS for radiobiological studies on targeted and non-targeted effects

    International Nuclear Information System (INIS)

    Esposito, G.; Antonelli, F.; Belli, M.; Campa, A.; Simone, G.; Sorrentino, E.; Tabocchini, M.A.

    2008-01-01

    In this paper we describe the alpha-particle irradiator that has been set up at the Istituto Superiore di Sanita (ISS) for controlled exposure of cultured mammalian cells. It can be equipped with two different sources, namely 2'4'4'Cm and 2'4'1'Am, allowing irradiation at different dose-rates (typically 1-100 mGy/min). The irradiator has dimensions small enough to be inserted into a standard cell culture incubator to perform irradiation of cultured cells in physiological conditions. The dose uniformity is such that the variations in the irradiation area are less than ± 12% of the average dose value on different irradiation areas up to ∼ 25 cm'2. Moreover, in the framework of the FP6 Euratom Integrated Project Non-targeted effects of ionizing radiation (NOTE), Petri dishes were realized for housing permeable membrane insert(s) to be used in co-culture experiments. Aluminium shields were also realized for half shield irradiation experiments. The alpha-particle irradiator of the ISS has been successfully used for studying DNA damage, namely double strand breaks (DSB, as measured by the γ-H2AX assay), in directly hit and in bystander primary human fibroblasts [it

  3. Determination of the accuracy for targeted irradiations of cellular substructures at SNAKE

    Energy Technology Data Exchange (ETDEWEB)

    Siebenwirth, C. [Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Greubel, C. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Drexler, S.E. [Department of Radiation Oncology, Ludwig-Maximilians-Universität München, Munich (Germany); Girst, S.; Reindl, J. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Walsh, D.W.M. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, Munich (Germany); Dollinger, G. [Institut für Angewandte Physik und Messtechnik (LRT2), Universität der Bundeswehr München, Neubiberg (Germany); Friedl, A.A. [Department of Radiation Oncology, Ludwig-Maximilians-Universität München, Munich (Germany); and others

    2015-04-01

    In the last 10 years the ion microbeam SNAKE, installed at the Munich 14 MV tandem accelerator, has been successfully used for radiobiological experiments by utilizing pattern irradiation without targeting single cells. Now for targeted irradiation of cellular substructures a precise irradiation device was added to the live cell irradiation setup at SNAKE. It combines a sub-micrometer single ion irradiation facility with a high resolution optical fluorescence microscope. Most systematic errors can be reduced or avoided by using the same light path in the microscope for beam spot verification as well as for and target recognition. In addition online observation of the induced cellular responses is possible. The optical microscope and the beam delivering system are controlled by an in-house developed software which integrates the open-source image analysis software, CellProfiler, for semi-automatic target recognition. In this work the targeting accuracy was determined by irradiation of a cross pattern with 55 MeV carbon ions on nucleoli in U2OS and HeLa cells stably expressing a GFP-tagged repair protein MDC1. For target recognition, nuclei were stained with Draq5 and nucleoli were stained with Syto80 or Syto83. The damage response was determined by live-cell imaging of MDC1-GFP accumulation directly after irradiation. No systematic displacement and a random distribution of about 0.7 μm (SD) in x-direction and 0.8 μm (SD) in y-direction were observed. An independent analysis after immunofluorescence staining of the DNA damage marker yH2AX yielded similar results. With this performance a target with a size similar to that of nucleoli (i.e. a diameter of about 3 μm) is hit with a probability of more than 80%, which enables the investigation of the radiation response of cellular subcompartments after targeted ion irradiation in the future.

  4. Determination of the accuracy for targeted irradiations of cellular substructures at SNAKE

    International Nuclear Information System (INIS)

    Siebenwirth, C.; Greubel, C.; Drexler, S.E.; Girst, S.; Reindl, J.; Walsh, D.W.M.; Dollinger, G.; Friedl, A.A.

    2015-01-01

    In the last 10 years the ion microbeam SNAKE, installed at the Munich 14 MV tandem accelerator, has been successfully used for radiobiological experiments by utilizing pattern irradiation without targeting single cells. Now for targeted irradiation of cellular substructures a precise irradiation device was added to the live cell irradiation setup at SNAKE. It combines a sub-micrometer single ion irradiation facility with a high resolution optical fluorescence microscope. Most systematic errors can be reduced or avoided by using the same light path in the microscope for beam spot verification as well as for and target recognition. In addition online observation of the induced cellular responses is possible. The optical microscope and the beam delivering system are controlled by an in-house developed software which integrates the open-source image analysis software, CellProfiler, for semi-automatic target recognition. In this work the targeting accuracy was determined by irradiation of a cross pattern with 55 MeV carbon ions on nucleoli in U2OS and HeLa cells stably expressing a GFP-tagged repair protein MDC1. For target recognition, nuclei were stained with Draq5 and nucleoli were stained with Syto80 or Syto83. The damage response was determined by live-cell imaging of MDC1-GFP accumulation directly after irradiation. No systematic displacement and a random distribution of about 0.7 μm (SD) in x-direction and 0.8 μm (SD) in y-direction were observed. An independent analysis after immunofluorescence staining of the DNA damage marker yH2AX yielded similar results. With this performance a target with a size similar to that of nucleoli (i.e. a diameter of about 3 μm) is hit with a probability of more than 80%, which enables the investigation of the radiation response of cellular subcompartments after targeted ion irradiation in the future

  5. Antitumor bystander effect induced by radiation-inducible target gene therapy combined with α particle irradiation

    International Nuclear Information System (INIS)

    Liu Hui; Jin Chufeng; Wu Yican; Ge Shenfang; Wu Lijun; FDS Team

    2012-01-01

    In this work, we investigated the bystander effect of the tumor and normal cells surrounding the target region caused by radiation-inducible target gene therapy combined with α-particle irradiation. The receptor tumor cell A549 and normal cell MRC-5 were co-cultured with the donor cells irradiated to 0.5 Gy or the non-irradiated donor cells, and their survival and apoptosis fractions were evaluated. The results showed that the combined treatment of Ad-ET and particle irradiation could induce synergistic antitumor effect on A549 tumor cell, and the survival fraction of receptor cells co-cultured with the irradiated cells decreased by 6%, compared with receptor cells co-cultured with non-irradiated cells, and the apoptosis fraction increased in the same circumstance, but no difference was observed with the normal cells. This study demonstrates that Ad-ET combined with α-particle irradiation can significantly cause the bystander effect on neighboring tumor cells by inhibiting cell growth and inducing apoptosis, without obvious toxicity to normal cells. This suggests that combining radiation-inducible TRAIL gene therapy and irradiation may improve tumor treatment efficacy by specifically targeting tumor cells and even involving the neighboring tumor cells. (authors)

  6. Search for Rayleigh-Taylor instability in laser irradiated layered thin foil targets

    International Nuclear Information System (INIS)

    Kilkenny, J.D.; Hares, J.D.; Rumsby, P.T.

    1980-01-01

    An experiment to measure the Rayleigh-Taylor instability at the vacuum-ablation surface of laser irradiated layered targets by time resolved x-ray spectroscopy is described. The time taken to burn through a layer of material is measured to be the same for massive targets as for thin foil accelerating targets. It is inferred that the thin foil targets might be Rayleigh-Taylor stable despite the values of γtauapproximately equal to15 calculated from classical theory. (author)

  7. TARPIPE: TARget Prototype Irradiations at PSI for EURISOL

    CERN Document Server

    E. Bouquerel1, R. Catherall1, S. Fernandes1, I. Guenther-Leopold2, F. Groeschel2, A. Kalt2, J.

    The selection of target materials for the production of radioactive nuclear beams is made on thebasis of several criteria that include the production cross-sections for isotopes of interest,diffusion, effusion, ageing and heat dissipation. Optimal target materials are often the result ofcompromises between these properties, which must be preserved under damaging operationconditions...

  8. Flat cladding and pellets in the design of an irradiation target

    International Nuclear Information System (INIS)

    Yorio, Daniel; Denis, Alicia C.; Soba, Alejandro; Beuter, Oscar; Marajofsky, Adolfo

    2003-01-01

    The design of an enriched uranium irradiation target made of flat pellets and cladding is proposed in order to improve the fission Mo 99 production. The variation range of each one of the parameters is studied and the basic design of the target is given

  9. Analysis of target implosion irradiated by proton beam, (1)

    International Nuclear Information System (INIS)

    Tamba, Moritake; Nagata, Norimasa; Kawata, Shigeo; Niu, Keishiro.

    1982-10-01

    Numerical simulation and analysis were performed for the implosion of a hollow shell target driven by proton beam. The target consists of three layers of Pb, Al and DT. As the Al layer is heated by proton beam, the layer expands and pushes the DT layer toward the target center. To obtain the optimal velocity of DT implosion, the optimal target size and optimal layer thickness were determined. The target size is determined by, for example, the instability of the implosion or beam focusing on the target surface. The Rayleigh-Taylor instability and the unstable implosion due to the inhomogeneity were investigated. Dissipation, nonlinear effects and density gradient at the boundary were expected to reduce the growth rate of the Rayleigh-Taylor instability during the implosion. In order that the deviation of the boundary surface during the implosion is less than the thickness of fuel, the inhomogeneity of the temperature and the density of the target should be less than ten percent. The amplitude of the boundary surface roughness is required to be less than 4 micrometer. (Kato, T.)

  10. Irradiation tests of 99Mo isotope production targets employing uranium metal foils

    International Nuclear Information System (INIS)

    Hofman, G.L.; Wiencek, T.C.; Wood, E.L.; Snelgrove, J.L.; Suripto, A.; Nasution, H.; Lufti-Amin, D.; Gogo, A.

    1996-01-01

    Most of the world's supply of 99 mTc for medical purposes is currently produced from the decay of 99 Mo derived from the fissioning of high-enriched uranium (HEU). Substitution of low-enriched uranium (LEU) metal foils for the HEU UO 2 used in current target designs will allow equivalent 99 Mo yields with little change in target geometries. Substitution of uranium metal for uranium alloy and aluminide in other target designs will also allow the conversion of HEU to LEU. Several uranium-metal-foil targets have been fabricated at ANL and irradiated to prototypic burnup in the Indonesian RSG-GAS reactor. Postirradiation examination of the initial test indicated that design modifications were required to allow the irradiated foil to be removed for chemical processing. The latest test has shown good irradiation behavior, satisfactory dismantling and foil removal when the U-foil is separated from its containment by metallic, fission-recoil absorbing barriers. (author)

  11. Irradiation tests of 99Mo isotope production targets employing uranium metal foils

    International Nuclear Information System (INIS)

    Hofman, G.L.; Wiencek, T.C.; Wood, E.L.; Snelgrove, J.L.; Suripto, A.; Nasution, H.; Lufti-Amin, D.; Gogo, A.

    1996-01-01

    Most of the world's supply of 99m Tc for medical purposes is currently produced form the decay of 99 Mo derived from the fissioning of high-enriched uranium (HEU). Substitution of low-enriched uranium (LEU) metal foils for the HEU UO 2 used in current target designs will allow equivalent 99 Mo yields with little change in target geometries. Substitution of uranium metal for uranium alloy and aluminide in other target designs will also allow the conversion of HEU to LEU. Several uranium-metal-foil targets have been fabricated at ANL and irradiated to prototypic burnup in the Indonesian RSG-GAS reactor. Postirradiation examination of the initial test indicated that design modifications were required to allow the irradiated foil to be removed for chemical processing. The latest test has shown good irradiation behavior, satisfactory dismantling and foil removal when the U-foil is separated from its containment by metallic, fission-recoil absorbing barriers

  12. A model for the acceleration of laser irradiated targets

    International Nuclear Information System (INIS)

    Babonneau, D.; Di Bona, G.; Fortin, X.

    1986-11-01

    Starting from the self-similar propagation of an electronic conduction wave and the consequent ablation pressure, we describe, in a simplified way, the shock ahead of this wave, then the effects of the rarefaction and compression waves which follow the shock emergence at the target rear surface. So, we obtain the temporal evolution of the rear velocity which is compared with the experimental one. For thick targets, the shock alone is able to emerge during the experimental time and consequently gives the velocity vsub(min). For thin targets, besides the shock accumulation mechanism, it is necessary to take into account the electronic heat wave emergence that is to say the ''complete'' ablation of the target which gives the velocity vsub(max)

  13. Statistical approach for calculating opacities of high-Z plasmas

    International Nuclear Information System (INIS)

    Nishikawa, Takeshi; Nakamura, Shinji; Takabe, Hideaki; Mima, Kunioki

    1992-01-01

    For simulating the X-ray radiation from laser produced high-Z plasma, an appropriate atomic modeling is necessary. Based on the average ion model, we have used a rather simple atomic model for opacity calculation in a hydrodynamic code and obtained a fairly good agreement with the experiment on the X-ray spectra from the laser-produced plasmas. We have investigated the accuracy of the atomic model used in the hydrodynamic code. It is found that transition energies of 4p-4d, 4d-4f, 4p-5d, 4d-5f and 4f-5g, which are important in laser produced high-Z plasma, can be given within an error of 15 % compared to the values by the Hartree-Fock-Slater (HFS) calculation and their oscillator strengths obtained by HFS calculation vary by a factor two according to the difference of charge state. We also propose a statistical method to carry out detail configuration accounting for electronic state by use of the population of bound electrons calculated with the average ion model. The statistical method is relatively simple and provides much improvement in calculating spectral opacities of line radiation, when we use the average ion model to determine electronic state. (author)

  14. Long-lived isotopes production in Pb-Bi target irradiated by high energy protons

    Energy Technology Data Exchange (ETDEWEB)

    Korovin, Y.A.; Konobeyev, A.Y.; Pereslavtsev, P.E. [Obninsk Institute of Nuclear Power Engineering, Obninsk (Russian Federation)

    1995-10-01

    Concentration of long-lived isotopes has been calculated for lead and lead-bismuth targets irradiated by protons with energy 0.4, 0.8, 1.0 and 1.6 GeV. The time of irradiation is equal from 1 month up to 2 years. The data libraries BROND, ADL and MENDL have been used to obtain the rate of nuclide transmutation. All calculations have been performed using the SNT code.

  15. Study of shock coalescence in laser-irradiated targets

    International Nuclear Information System (INIS)

    Coe, S.E.; Willi, O.; Afshar-Rad, T.; Rose, S.J.

    1988-01-01

    We report on the first direct experimental observation of the coalescence of two shocks induced by a shaped laser pulse. Optical streak photography of the rear surface of aluminum multiple step targets was used to study the breakout of these shocks and observe their behavior. The experimental results are compared with simulations by a one-dimensional Lagrangian hydrodynamic code

  16. Shock dynamics induced by double-spot laser irradiation of layered targets

    Directory of Open Access Journals (Sweden)

    Aliverdiev Abutrab A.

    2015-06-01

    Full Text Available We studied the interaction of a double-spot laser beam with targets using the Prague Asterix Laser System (PALS iodine laser working at 0.44 μm wavelength and intensity of about 1015 W/cm2. Shock breakout signals were recorder using time-resolved self-emission from target rear side of irradiated targets. We compared the behavior of pure Al targets and of targets with a foam layer on the laser side. Results have been simulated using hydrodynamic numerical codes.

  17. A wide temperature range irradiation cryostat for reasearch on solid state targets

    Energy Technology Data Exchange (ETDEWEB)

    Reeve, Scott; Dutz, Hartmut; Goertz, Stefan; Runkel, Stefan; Voge, Thomas [Physikalisches Institut, Universitaet Bonn (Germany)

    2012-07-01

    To qualitatively improve the data obtained in asymmetry measurements of scattering experiments the figure of merit (FOM) plays a major role and can reduce the data acquisition time when a certain precision in the measurement is needed. One of the defining factors for the improvement of the polarised experiment lies in the target choice and preparation, in particular the method employed to introduce the paramagnetic defects for the use of dynamic nuclear polarisation (DNP). To this end the Polarized Target Group in Bonn has developed a wide range temperature cryostat for the irradiation of potential target materials in which materials can be irradiated to varying doses at specified temperatures. The stable irradiation temperature of the materials can be controlled to within {+-}1 K over a range of 90 K

  18. Solvent extraction of irradiated neptunium targets. I. Valence stabilization

    International Nuclear Information System (INIS)

    Thompson, G.H.; Thompson, M.C.

    1977-01-01

    Solvent extraction of 237 Np and 238 Pu from irradiated neptunium is being investigated as a possible replacement for the currently used anion exchange process at the Savannah River Plant. Solvent extraction would reduce separations costs and waste volume and increase the production rate. The major difficulty in solvent extraction processing is maintaining neptunium and plutonium in the extractable IV or VI valence states during initial extraction. This study investigated the stability of these states. Results show that: The extractable M(IV) valence states of neptunium and plutonium are mutually unstable in plant dissolver solution (2 g/l 237 Np, 0.4 g/l 238 Pu, 1.2M Al 3+ , 4.6M NO 3 - , and 1M H + ). The reaction rates producing inextractable species from extractable M(IV) or M(VI) are fast enough that greater than or equal to 99.9 percent extractable species in 237 Np-- 238 Pu mixtures cannot be maintained for a practicable processing period

  19. Imaging of High-Z doped, Imploded Capsule Cores

    Science.gov (United States)

    Prisbrey, Shon T.; Edwards, M. John; Suter, Larry J.

    2006-10-01

    The ability to correctly ascertain the shape of imploded fusion capsules is critical to be able to achieve the spherical symmetry needed to maximize the energy yield of proposed fusion experiments for the National Ignition Facility. Implosion of the capsule creates a hot, dense core. The introduction of a high-Z dopant into the gas-filled core of the capsule increases the amount of bremsstrahlung radiation produced in the core and should make the imaging of the imploded core easier. Images of the imploded core can then be analyzed to ascertain the symmetry of the implosion. We calculate that the addition of Ne gas into a deuterium gas core will increase the amount of radiation emission while preserving the surrogacy of the radiation and hydrodynamics in the indirect drive NIF hohlraum in the proposed cryogenic hohlraums. The increased emission will more easily enable measurement of asymmetries and tuning of the implosion.

  20. Opacity calculations and Saha's equation for high Z elements

    International Nuclear Information System (INIS)

    Godwal, B.K.; Sikka, S.K.

    1977-01-01

    Opacity calculations are needed for energy transport by radiation for high Z element plasmas as these have been suggested as temper materials in laser, electron beam and heavy ion fusion schemes. The pressure ionised modified form of Saha's ionisation equation has been used to obtain the free electron density, populations of various ionic species and the populations of various energy states for a given ion. Results are presented for two typical elements; tungsten and uranium. The ionisation potential have been evaluated using the Bohr's formula with suitable effective screened charges for ions. The results show that for uranium, even at a temperature of 10 kev, the K shell is intact. The reliability of the Saha's equation solution has been checked by comparing the equation of state (total pressure vs total energy curve) with that given by the Thomas-Fermi-Dirac equation of state. The agreement between the two is good from temperature upwards of 0.2 kev. (author)

  1. High-z Universe with Gamma Ray Bursts

    Science.gov (United States)

    Kouveliotou, C.

    2011-01-01

    Gamma-Ray Bursts (GRBs) are the most luminous explosions in space and trace the cosmic star formation history back to the first generations of stars. Their bright afterglows allow us to trace the abundances of heavy elements to large distances, thereby measuring cosmic chemical evolution. To date GRBs have been detected up to distances of z=8.23 and possibly even beyond z9. This makes GRBs a unique and powerful tool to probe the high-z Universe up to the re-ionization era. We discuss the current status of the field, place it in context with other probes, and also discuss new mission concepts that have been planned to utilize GRBs as probes.

  2. Separation of Plutonium from Irradiated Fuels and Targets

    Energy Technology Data Exchange (ETDEWEB)

    Gray, Leonard W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Holliday, Kiel S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Murray, Alice [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Thompson, Major [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Thorp, Donald T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Yarbro, Stephen [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Venetz, Theodore J. [Hanford Site, Benton County, WA (United States)

    2015-09-30

    Spent nuclear fuel from power production reactors contains moderate amounts of transuranium (TRU) actinides and fission products in addition to the still slightly enriched uranium. Originally, nuclear technology was developed to chemically separate and recover fissionable plutonium from irradiated nuclear fuel for military purposes. Military plutonium separations had essentially ceased by the mid-1990s. Reprocessing, however, can serve multiple purposes, and the relative importance has changed over time. In the 1960’s the vision of the introduction of plutonium-fueled fast-neutron breeder reactors drove the civilian separation of plutonium. More recently, reprocessing has been regarded as a means to facilitate the disposal of high-level nuclear waste, and thus requires development of radically different technical approaches. In the last decade or so, the principal reason for reprocessing has shifted to spent power reactor fuel being reprocessed (1) so that unused uranium and plutonium being recycled reduce the volume, gaining some 25% to 30% more energy from the original uranium in the process and thus contributing to energy security and (2) to reduce the volume and radioactivity of the waste by recovering all long-lived actinides and fission products followed by recycling them in fast reactors where they are transmuted to short-lived fission products; this reduces the volume to about 20%, reduces the long-term radioactivity level in the high-level waste, and complicates the possibility of the plutonium being diverted from civil use – thereby increasing the proliferation resistance of the fuel cycle. In general, reprocessing schemes can be divided into two large categories: aqueous/hydrometallurgical systems, and pyrochemical/pyrometallurgical systems. Worldwide processing schemes are dominated by the aqueous (hydrometallurgical) systems. This document provides a historical review of both categories of reprocessing.

  3. Momenta of particles emitted by target at intensive irradiation by low-energy ions

    CERN Document Server

    Beshenkov, V G; Marchenko, V A

    2002-01-01

    One measured the aggregate momenta of the target emitted particles at the intensive sputtering by E sub 0 approx = 0.5 keV energy heavy inert gases. For liquid and being under premelting temperature Ga target the measured values are close to the expected momenta of sputtered metallic atoms and reflection ions, for Cu and Zr targets they are essentially higher. One assumes that sputtering of atoms of gas-diffuser implanted into the target causes the surplus momentum. The estimated average energy of these atoms approx = 20 eV. Under Ga irradiation the implanted atoms diffuse mainly towards the surface and are desorbed

  4. Separation of heavier rare earths from neutron irradiated uranium targets

    International Nuclear Information System (INIS)

    Bhargava, V.K.; Rao, V.K.; Marathe, S.G.; Sahakundu, S.M.; Iyer, R.H.

    1978-01-01

    A radiochemical method is described for the separation of heavier rare earths from the fission of uranium. The method is particularly suitable for the separation of low yield (10sup(-5)%-10sup(-7)%), highly asymmetric rare earth fission products viz. sup(179,177)Lu, sup(175)Yb, sup(173)Tm, sup(172,171)Er, sup(167)Ho and sup(161,160)Tb in the neutron induced fission of natural and depleted uranium targets. Additional separation steps have been incorporated for decontamination from sup(239)Np (an activation product) and sup(93-90)Y (a high fission-yield product) which show similar chemical behaviour to rare earths. Separation of individual rare earths is achieved by a cation exchange method performed at 80 deg C by elution with α-hydroxyisobutyric acid (α-HIBA). (author)

  5. Compaction and sintering of nickel powder used encapsulation of irradiation targets

    International Nuclear Information System (INIS)

    Miyano, Rosana S.L.; Guimaraes, Raquel R.F.L.; Rossi, Jesualdo L.; Wendhausen, Paulo A.P.; Evangelista, Leandro L.

    2015-01-01

    The objective of this study was to develop an alternative way to produce targets for irradiation containing uranium, for the pair of 99 Mo production 99m Tc radionuclide. These targets were obtained by powder metallurgy, the compact serving as means for encapsulation a uranium cylinder to be irradiated. The targets were compacted in an axial hydraulic press applying different pressures up to 800 MPa. The sintering temperature was 600 °C in hydrogen atmosphere and it was used two sintering cycles, one for 4 h and the for 4 h plus 8 h time. The nickel powder was of high purity, that in order to provide the sealing of the fissile content within the compacted. The bulk density of compacted was evaluated by the method geometric. The porosity was measured by mercury porosimetry technique. The microstructure was investigated by optical microscopy. The results obtained with sintering powders involving confirm the feasibility of achieving a casing for uranium targets. (author)

  6. Study of intense pulse irradiation effects on silicon targets considered as ground matter for optical detectors

    International Nuclear Information System (INIS)

    Muller, O.

    1994-12-01

    This study aim was centered on morphological and structural alterations induced by laser irradiation on silicon targets considered as ground matter for optical detectors. First we recalled the main high light intensity effects on the condensed matter. Then we presented the experimental aspects. The experimental studies were achieved on two sample types: SiO 2 /Si and Si. Two topics were studied: the defect chronology according to wavelength and pulse length, and the crystalline quality as well as the structure defects of irradiated zones by Raman spectroscopy. Finally, irradiation of Si targets by intense pulsed beams may lead to material fusion. This phenomenon is particularly easy when the material is absorbent, when the pulse is short and when the material is superficially oxidized. (MML). 204 refs., 93 figs., 21 tabs., 1 appendix

  7. Soviet paper on laser target heating, symmetry of irradiation, and two-dimensional effects on compression

    International Nuclear Information System (INIS)

    Sahlin, H.L.

    1976-01-01

    Included is a paper presented at the Annual Meeting of the Plasma Physics Division of the American Physical Society in San Francisco on November 19, 1976. The paper discusses some theoretical problems of laser target irradiation and compression investigated at the laboratory of quantum radiophysics of Lebedev Physical Institute. Of significant interest was the absorption and reflection of laser radiation in the corona plasma of a laser target

  8. Stopping power and range relations for low and high Z ions in solids: a critical analysis

    International Nuclear Information System (INIS)

    Virk, H.S.; Randhawa, G.S.

    1997-01-01

    A critical analysis of various stopping power and range formulations has been made by comparing the calculated stopping power and range values with corresponding experimental values for different low Z (1≤Z≤8) and high Z projectiles (54≤Z≤92) in different targets, e.g. Be, C, Al, Au, Pb, CR-39, Lexan, Mylar, LR-115, CH, (CH)n, TRIFOL-TN, etc. atvarious low and high energies. A comparative study has been made by taking into consideration different target and projectile combinations, e.g., heavy ion-light target, light ion-heavy target and light ion -light target etc., Overall the Ziegler formulation (TRIM-95) provides the best agreement with the experimental results for all projectile and target combinations except for heavy ion-light target combination where it underestimates the stopping power data and overestimates the range data in the range, 2-50 MeV/u. Mukherjee and Nayak formulation totally fails at relativistic and low energies of the projectile, irrespective of the projectile-target combination. Northcliffe and Schilling formulation does not show any particular trend. Benton and Henke formulation gives good agreement between experimental and theoretical data within the range of experimental errors. (orig.)

  9. Intravesical markers for delineation of target volume during external focal irradiation of bladder carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Hulshof, Maarten C.C.M. [Department of Radiation Oncology, University of Amsterdam (Netherlands)]. E-mail: m.c.hulshof@amc.uva.nl; Andel, George van [Department of Urology, Onze Lieve Vrouwe Gasthuis, Amsterdam (Netherlands); Bel, Arjen [Department of Radiation Oncology, University of Amsterdam (Netherlands); Gangel, Pieter [Department of Radiation Oncology, University of Amsterdam (Netherlands); Kamer, Jeroen B. van de [Department of Radiation Oncology, University of Amsterdam (Netherlands)

    2007-07-15

    A clip forceps was developed which can insert markers at the border of a bladder tumour through a rigid cystoscope. This technique proved to be simple and safe and is of help for delineation of the target volume during CT simulation for focal boost irradiation of bladder cancer.

  10. Intravesical markers for delineation of target volume during external focal irradiation of bladder carcinomas

    International Nuclear Information System (INIS)

    Hulshof, Maarten C.C.M.; Andel, George van; Bel, Arjen; Gangel, Pieter; Kamer, Jeroen B. van de

    2007-01-01

    A clip forceps was developed which can insert markers at the border of a bladder tumour through a rigid cystoscope. This technique proved to be simple and safe and is of help for delineation of the target volume during CT simulation for focal boost irradiation of bladder cancer

  11. Intravesical markers for delineation of target volume during external focal irradiation of bladder carcinomas.

    Science.gov (United States)

    Hulshof, Maarten C C M; van Andel, George; Bel, Arjen; Gangel, Pieter; van de Kamer, Jeroen B

    2007-07-01

    A clip forceps was developed which can insert markers at the border of a bladder tumour through a rigid cystoscope. This technique proved to be simple and safe and is of help for delineation of the target volume during CT simulation for focal boost irradiation of bladder cancer.

  12. Post Irradiation Examination Results of the NT-02 Graphite Fins NUMI Target

    Energy Technology Data Exchange (ETDEWEB)

    Ammigan, K. [Fermilab; Hurh, P. [Fermilab; Sidorov, V. [Fermilab; Zwaska, R. [Fermilab; Asner, D. M. [PNL, Richland; Casella, Casella,A.M [PNL, Richland; Edwards, D. J. [PNL, Richland; Schemer-Kohrn, A. L. [PNL, Richland; Senor, D. J. [PNL, Richland

    2017-02-10

    The NT-02 neutrino target in the NuMI beamline at Fermilab is a 95 cm long target made up of segmented graphite fins. It is the longest running NuMI target, which operated with a 120 GeV proton beam with maximum power of 340 kW, and saw an integrated total proton on target of 6.1 1020. Over the last half of its life, gradual degradation of neutrino yield was observed until the target was replaced. The probable causes for the target performance degradation are attributed to radiation damage, possibly including cracking caused by reduction in thermal shock resistance, as well as potential localized oxidation in the heated region of the target. Understanding the long-termstructural response of target materials exposed to proton irradiation is critical as future proton accelerator sources are becoming increasingly more powerful. As a result, an autopsy of the target was carried out to facilitate post-irradiation examination of selected graphite fins. Advanced microstructural imaging and surface elemental analysis techniques were used to characterize the condition of the fins in an effort to identify degradation mechanisms, and the relevant findings are presented in this paper.

  13. Validation of a new design of tellurium dioide-irradiated target

    Energy Technology Data Exchange (ETDEWEB)

    Fllaoui, Aziz; Ghamad, Younes; Zoubir, Brahim; Ayaz, Zinel Abidine; El Morabiti, Aissam; Amayoud, Hafid [Centre National de l' Energie des Sciences et des Techniques Nucleaires, Rabat (Morocco); Chakir, El Mahjoub [Nuclear Physics Department, University Ibn Toufail, Kenitra (Morocco)

    2016-10-15

    Production of iodine-131 by neutron activation of tellurium in tellurium dioxide (TeO{sub 2}) material requires a target that meets the safety requirements. In a radiopharmaceutical production unit, a new lid for a can was designed, which permits tight sealing of the target by using tungsten inert gas welding. The leakage rate of all prepared targets was assessed using a helium mass spectrometer. The accepted leakage rate is ≤ 10 - 4 mbr.L/s, according to the approved safety report related to iodine-131 production in the TRIGA Mark II research reactor (TRIGA: Training, Research, Isotopes, General Atomics). To confirm the resistance of the new design to the irradiation conditions in the TRIGA Mark II research reactor's central thimble, a study of heat effect on the sealed targets for 7 hours in an oven was conducted and the leakage rates were evaluated. The results show that the tightness of the targets is ensured up to 600 .deg. C with the appearance of deformations on lids beyond 450 .deg. C. The study of heat transfer through the target was conducted by adopting a one-dimensional approximation, under consideration of the three transfer modes-convection, conduction, and radiation. The quantities of heat generated by gamma and neutron heating were calculated by a validated computational model for the neutronic simulation of the TRIGA Mark II research reactor using the Monte Carlo N-Particle transport code. Using the heat transfer equations according to the three modes of heat transfer, the thermal study of I-131 production by irradiation of the target in the central thimble showed that the temperatures of materials do not exceed the corresponding melting points. To validate this new design, several targets have been irradiated in the central thimble according to a preplanned irradiation program, going from 4 hours of irradiation at a power level of 0.5 MW up to 35 hours (7 h/d for 5 days a week) at 1.5 MW. The results show that the irradiated targets are

  14. Validation of a New Design of Tellurium Dioxide-Irradiated Target

    Directory of Open Access Journals (Sweden)

    Aziz Fllaoui

    2016-10-01

    Full Text Available Production of iodine-131 by neutron activation of tellurium in tellurium dioxide (TeO2 material requires a target that meets the safety requirements. In a radiopharmaceutical production unit, a new lid for a can was designed, which permits tight sealing of the target by using tungsten inert gas welding. The leakage rate of all prepared targets was assessed using a helium mass spectrometer. The accepted leakage rate is ≤ 10−4 mbr.L/s, according to the approved safety report related to iodine-131 production in the TRIGA Mark II research reactor (TRIGA: Training, Research, Isotopes, General Atomics. To confirm the resistance of the new design to the irradiation conditions in the TRIGA Mark II research reactor's central thimble, a study of heat effect on the sealed targets for 7 hours in an oven was conducted and the leakage rates were evaluated. The results show that the tightness of the targets is ensured up to 600°C with the appearance of deformations on lids beyond 450°C. The study of heat transfer through the target was conducted by adopting a one-dimensional approximation, under consideration of the three transfer modes—convection, conduction, and radiation. The quantities of heat generated by gamma and neutron heating were calculated by a validated computational model for the neutronic simulation of the TRIGA Mark II research reactor using the Monte Carlo N-Particle transport code. Using the heat transfer equations according to the three modes of heat transfer, the thermal study of I-131 production by irradiation of the target in the central thimble showed that the temperatures of materials do not exceed the corresponding melting points. To validate this new design, several targets have been irradiated in the central thimble according to a preplanned irradiation program, going from 4 hours of irradiation at a power level of 0.5 MW up to 35 hours (7 h/d for 5 days a week at 1.5 MW. The results show that the irradiated targets are

  15. Beyond Extreme Ultra Violet (BEUV) Radiation from Spherically symmetrical High-Z plasmas

    Science.gov (United States)

    Yoshida, Kensuke; Fujioka, Shinsuke; Higashiguchi, Takeshi; Ugomori, Teruyuki; Tanaka, Nozomi; Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryouichi; Eshima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Scally, Enda; Nshimura, Hiroaki; Azechi, Hiroshi; O'Sullivan, Gerard

    2016-03-01

    Photo-lithography is a key technology for volume manufacture of high performance and compact semiconductor devices. Smaller and more complex structures can be fabricated by using shorter wavelength light in the photolithography. One of the most critical issues in development of the next generation photo-lithography is to increase energy conversion efficiency (CE) from laser to shorter wavelength light. Experimental database of beyond extreme ultraviolet (BEUV) radiation was obtained by using spherically symmetrical high-Z plasmas generated with spherically allocated laser beams. Absolute energy and spectra of BEUV light emitted from Tb, Gd, and Mo plasmas were measured with a absolutely calibrated BEUV calorimeter and a transmission grating spectrometer. 1.0 x 1012 W/cm2 is the optimal laser intensity to produced efficient BEUV light source plasmas with Tb and Gd targets. Maximum CE is achieved at 0.8% that is two times higher than the published CEs obtained with planar targets.

  16. SHARDS: Survey for High-z Absorption Red & Dead Sources

    Science.gov (United States)

    Pérez-González, P. G.; Cava, A.

    2013-05-01

    SHARDS, an ESO/GTC Large Program, is an ultra-deep (26.5 mag) spectro-photometric survey with GTC/OSIRIS designed to select and study massive passively evolving galaxies at z=1.0-2.3 in the GOODS-N field using a set of 24 medium-band filters (FWHM~17 nm) covering the 500-950 nm spectral range. Our observing strategy has been planned to detect, for z>1 sources, the prominent Mg absorption feature (at rest-frame ~280 nm), a distinctive, necessary, and sufficient feature of evolved stellar populations (older than 0.5 Gyr). These observations are being used to: (1) derive for the first time an unbiased sample of high-z quiescent galaxies, which extends to fainter magnitudes the samples selected with color techniques and spectroscopic surveys; (2) derive accurate ages and stellar masses based on robust measurements of spectral features such as the Mg_UV or D(4000) indices; (3) measure their redshift with an accuracy Δz/(1+z)<0.02; and (4) study emission-line galaxies (starbursts and AGN) up to very high redshifts. The well-sampled optical SEDs provided by SHARDS for all sources in the GOODS-N field are a valuable complement for current and future surveys carried out with other telescopes (e.g., Spitzer, HST, and Herschel).

  17. Target volume delineation in external beam partial breast irradiation: Less inter-observer variation with preoperative- compared to postoperative delineation

    International Nuclear Information System (INIS)

    Leij, Femke van der; Elkhuizen, Paula H.M.; Janssen, Tomas M.; Poortmans, Philip; Sangen, Maurice van der; Scholten, Astrid N.; Vliet-Vroegindeweij, Corine van; Boersma, Liesbeth J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of twenty-four breast cancer patients

  18. Target volume delineation in external beam partial breast irradiation: less inter-observer variation with preoperative- compared to postoperative delineation

    NARCIS (Netherlands)

    Leij, F. van der; Elkhuizen, P.H.M.; Janssen, T.M.; Poortmans, P.M.P.; Sangen, M. van der; Scholten, A.N.; Vliet-Vroegindeweij, C. van; Boersma, L.J.

    2014-01-01

    The challenge of adequate target volume definition in external beam partial breast irradiation (PBI) could be overcome with preoperative irradiation, due to less inter-observer variation. We compared the target volume delineation for external beam PBI on preoperative versus postoperative CT scans of

  19. Influence of neutron energy on formation of radioisotopes during the irradiation of targets in reactor

    Directory of Open Access Journals (Sweden)

    P. M. Vorona

    2011-09-01

    Full Text Available Method of calculation of nuclear transformations in irradiated targets is realized for selection of optimal conditions for accumulation of radioisotopes in reactor, taking into account contributions of different energy neutrons (thermal, resonance and fast. Wide potentialities of program complex MCNP-4C based on the method of statistical testing (Monte Carlo method were used. Positive in proposed method is that all calculations starting from spectra and fluxes of neutrons in reactor and completing by quantity of accumulating nuclei carry out within the framework of the same methodological approach. It was shown by the example of radioactive 98Mo production in Mo98Mo(n, γ99Mo reaction that for achievement of maximal yield of target radionuclide. it is necessary to irradiate start targets of Molybdenum in hard spectrum with essential contribution of resonance neutrons.

  20. HTCAP-1: a program for calcuating operating temperatures in HFIR target irradiation experiments

    International Nuclear Information System (INIS)

    Kania, M.J.; Howard, A.M.

    1980-06-01

    The thermal modeling code, HTCAP-1, calculates in-reactor operating temperatures of fueled specimens contained in the High Flux Isotope Reactor (HFIR) target irradiation experiments (HT-series). Temperature calculations are made for loose particle and bonded fuel rod specimens. Maximum particle surface temperatures are calculated for the loose particles and centerline and surface temperatures for the fuel rods. Three computational models are employed to determine fission heat generation rates, capsule heat transfer analysis, and specimen temperatures. This report is also intended to be a users' manual, and the application of HTCAP-1 to the HT-34 irradiation capsule is presented

  1. Analysis of uranium and thorium thin targets irradiated at the PSI accelerator

    International Nuclear Information System (INIS)

    Wenger, H.U.; Botta, F.; Chawla, R.; Daum, M.; Gavillet, D.; Hegedues, F.; Ingold, F.; Kopajtic, Z.; Ledergerber, G.; Linder, H.P.; Roellin, S.; Wichser, J.; Wyss, F.

    1997-01-01

    The aim of the ATHENA programme at PSI is to provide experimental data for the validation of theoretical models in nucleon-meson transport codes used for accelerator-based transmutation studies. Emphasis is placed on the mass yield distribution of spallation and fission products for irradiated thin actinide targets. This paper presents results of an irradiation experiment carried out with 238 UO 2 and 232 ThO 2 . Isobaric production cross-sections of fission and spallation products based on mass spectrometric measurements and γ-spectroscopy are compared with calculations carried out using the HETC code and the RAL high-energy fission model. (author) 6 figs., 8 refs

  2. Post-Irradiation Examination of 237Np Targets for 238Pu Production

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Robert Noel [ORNL; Baldwin, Charles A [ORNL; Hobbs, Randy W [ORNL; Schmidlin, Joshua E [ORNL

    2015-01-01

    Oak Ridge National Laboratory is recovering the US 238Pu production capability and the first step in the process has been to evaluate the performance of a 237Np target cermet pellet encased in an aluminum clad. The process proceeded in 3 steps; the first step was to irradiate capsules of single pellets composed of NpO2 and aluminum power to examine their shrinkage and gas release. These pellets were formed by compressing sintered NpO2 and aluminum powder in a die at high pressure followed by sintering in a vacuum furnace. Three temperatures were chosen for sintering the solution precipitated NpO2 power used for pellet fabrication. The second step was to irradiate partial targets composed of 8 pellets in a semi-prototypical arrangement at the two best performing sintering temperatures to determine which temperature gave a pellet that performed the best under the actual planned irradiation conditions. The third step was to irradiate ~50 pellets in an actual target configuration at design irradiation conditions to assess pellet shrinkage and gas release, target heat transfer, and dimensional stability. The higher sintering temperature appeared to offer the best performance after one cycle of irradiation by having the least shrinkage, thus keeping the heat transfer gap between the pellets and clad small minimizing the pellet operating temperature. The final result of the testing was a target that can meet the initial production goals, satisfy the reactor safety requirements, and can be fabricated in production quantities. The current focus of the program is to verify that the target can be remotely dissembled, the pellets dissolved, and the 238Pu recovered. Tests are being conducted to examine these concerns and to compare results to code predictions. Once the performance of the full length targets has been quantified, the pellet 237Np loading will be revisited to determine if it can be

  3. Optimum combination of targeted 131I and total body irradiation for treatment of disseminated cancer

    International Nuclear Information System (INIS)

    Amin, Amin E.; Wheldon, Tom E.; O'Donoghue, Joseph A.; Gaze, Mark N.; Barrett, Ann

    1995-01-01

    Purpose: Radiobiological modeling was used to explore optimum combination strategies for treatment of disseminated malignancies of differing radiosensitivity and differing patterns of metastatic spread. The purpose of the study was to derive robust conclusions about the design of combination strategies that incorporate a targeting component. Preliminary clinical experience of a neuroblastoma treatment strategy, which is based upon general principles obtained from modelling, is briefly described. Methods and Materials: The radiobiological analysis was based on an extended (dose-rate dependent) formulation of the linear quadratic model. Radiation dose and dose rate for targeted irradiation of tumors of differing size was in part based on microdosimetric considerations. The analysis was applied to several tumor types with postulated differences in the pattern of metastatic spread, represented by the steepness of the slope of the relationship between numbers of tumors present and tumor diameter. The clinical pilot study entailed the treatment of five children with advanced neuroblastoma using a combination of 131 I metaiodobenzylguanidine (mIBG) and total body irradiation followed by bone marrow rescue. Results: The theoretical analysis shows that both intrinsic radiosensitivity and pattern of metastatic spread can influence the composition of the ideal optimum combination strategy. High intrinsic radiosensitivity generally favors a high proportion of targeting component in the combination treatment, while a strong tendency to micrometastatic spread favors a major contribution by total body irradiation. The neuroblastoma patients were treated using a combination regimen with an initially low targeting component (2 Gy whole body dose from targeting component plus 12 Gy from total body irradiation). The treatment was tolerable and resulted in remissions in excess of 9 months in each of these advanced neuroblastoma patients. Conclusions: Radiobiological analysis, which

  4. Irradiated NH3 and ND3 - two new target materials for polarized targets

    International Nuclear Information System (INIS)

    Meyer, W.

    1982-11-01

    A study of dynamic nuclear polarization (DNP) in NH 3 and ND 3 was made at the Bonn 2.5 GeV electron synchrotron. The paramagnetic radicals in the polycristalline ammonia beads were created by irradiation in the high intensity 20 MeV electron beam (> 10 14 electrons/sec) of the injection linac. During irradiation the ammonia beads, produced by dropping into liquid nitrogen, were cooled in liquid argon at approx.= 90 K. DNP measurements were performed at 1 K, 0.5 K and 0.2 K in a 2.5 T magnetic field. Samples of NH 3 , prepared in this way, yielded a maximum proton polarization of 66% at a temperature of 0.5 K with a short polarization build-up time of 9 minutes. ND 3 could be polarized at a temperature of 0.2 K up to 31%. The radiation resistance of the polarization of NH 3 is better than that of butanol. (orig.)

  5. Neutronic and thermal hydraulic analyses of LEU targets irradiated in a research reactor for Molybdenum-99 production

    International Nuclear Information System (INIS)

    Jo, Daeseong; Lee, Kyung-Hoon; Kim, Hong-Chul; Chae, Heetaek

    2014-01-01

    Highlights: • Neutronic and thermal hydraulic analyses of irradiated fuel plates for Molybdenum-99. • Heat production during and after irradiation was evaluated using MCNP and ORIGEN-APR. • Cooling capacities under various cooling conditions were evaluated using TMAP. • Natural convective cooling was adequate for the decay power after 0.03 h from withdrawal. • Maximum temperature of the target decayed for 24 h does not exceed the blistering threshold. - Abstract: Neutronic and thermal hydraulic analyses of irradiated fuel plates for Molybdenum-99 production in a research reactor were performed to investigate (1) the heat production during irradiation, (2) decay heat after irradiation, and (3) cooling capacities under various cooling conditions. The heat production on the target plates irradiated in the core was evaluated using the MCNP code. The decay heat after irradiation was evaluated using the ORIGEN-APR code, and compared against ANSI/ANS-5.1-1979. The cooling capacities of forced convective cooling during irradiation and natural convective cooling after irradiation were estimated using the TMAP code. An equilibrium core with different core statuses i.e., BOC, MOC, and EOC was used to evaluate power released from the targets and the axial power distribution. Based on the neutronic calculations, thermal margins i.e., the maximum wall temperature, minimum ONB temperature margin, and minimum CHF ratio were estimated, and the cooling strategy of the fission Mo targets was discussed. The targets were cooled by forced convective cooling during irradiation, and cooled by natural convective cooling after irradiation. For a further production process, the targets transported to a hot cell were exposed to the air, and cooled by natural convection cooling in air. As a result, the maximum wall temperature remained below the ONB temperature while the targets were under water, and the maximum wall temperature remained under the blistering limit while the targets

  6. Thermal analysis of LEU modified Cintichem target irradiated in TRIGA reactor

    International Nuclear Information System (INIS)

    Catana, A; Toma, C.

    2009-01-01

    Actions conceived during last years at international level for conversion of Molybdenum fabrication process from HEU to LEU targets utilization created opportunities for INR to get access to information and participating to international discussions under IAEA auspices. Concrete steps for developing fission Molybdenum technology were facilitated. Institute of Nuclear Research bringing together a number of conditions like suitable irradiation possibilities, direct communication between reactor and hot cell facility, handling capacity of high radioactive sources, and simultaneously the existence of an expanding internal market, decided to undertake the necessary steps in order to produce fission molybdenum. Over the course of last years of efforts in this direction we developed the steps for fission Molybdenum technology development based on modified Cintichem process in accordance with the Argonne National Laboratory proved methodology. Progress made by INR to heat transfer computations of annular target using is presented. An advanced thermal-hydraulic analysis was performed to estimate the heat removal capability for an enriched uranium (LEU) foil annular target irradiated in TRIGA reactor core. As a result, the present analysis provides an upper limit estimate of the LEU-foil and external target surface temperatures during irradiation in TRIGA 14 MW reactor. (authors)

  7. Synthesis of Specific Nanoparticles for Targeting and Imaging Tumor Angiogenesis Using Electron-Beam Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Rizza, G.; Deshayes, S.; Maurizot, V.; Clochard, M. -C.; Berthelot, T.; Baudin, C.; Déléris, G., E-mail: giancarlo.rizza@polytechnique.edu [Commissariat à l' énergie atomique (CEA), Institut Rayonnement Matière de Saclay (IRaMIS), B.P. 52, 91191 Gif Sur Yvette Cedex (France)

    2010-07-01

    We have succeeded to synthesize PVDF nanoparticles by nanoemulsion polymerization and their functionalization with a peptide that presents an anti-angiogenic activity. Resulted nanoparticles present a radius of 60 nm. From FESEM images and light scattering measurements, we deduced that they were spherical and monodisperse. The alkyl radicals induced from electron beam irradiation combine immediately with the oxygen to form peroxide radicals. Because of a high specific area and small crystallite size, the radical decay with time is evidenced from EPR measurements. Despite this radical decay, electron beam irradiation allows us to graft PAA by radical polymerization onto freshly irradiated PVDF nanoparticles and then to immobilize CBO-P11 by click chemistry via a spacer arm. Evidences of grafting were shown using HRMAS NMR and MALDI-TOF mass spectrometry. Nanoparticles functionalized with an angiogenesis-targeting agent are an attractive option for anti-tumor therapy.

  8. Synthesis of Specific Nanoparticles for Targeting and Imaging Tumor Angiogenesis Using Electron-Beam Irradiation

    International Nuclear Information System (INIS)

    Rizza, G.; Deshayes, S.; Maurizot, V.; Clochard, M.-C.; Berthelot, T.; Baudin, C.; Déléris, G.

    2010-01-01

    We have succeeded to synthesize PVDF nanoparticles by nanoemulsion polymerization and their functionalization with a peptide that presents an anti-angiogenic activity. Resulted nanoparticles present a radius of 60 nm. From FESEM images and light scattering measurements, we deduced that they were spherical and monodisperse. The alkyl radicals induced from electron beam irradiation combine immediately with the oxygen to form peroxide radicals. Because of a high specific area and small crystallite size, the radical decay with time is evidenced from EPR measurements. Despite this radical decay, electron beam irradiation allows us to graft PAA by radical polymerization onto freshly irradiated PVDF nanoparticles and then to immobilize CBO-P11 by click chemistry via a spacer arm. Evidences of grafting were shown using HRMAS NMR and MALDI-TOF mass spectrometry. Nanoparticles functionalized with an angiogenesis-targeting agent are an attractive option for anti-tumor therapy

  9. Irradiation promotes Akt-targeting therapeutic gene delivery to the tumor vasculature

    International Nuclear Information System (INIS)

    Sonveaux, Pierre; Frerart, Francoise; Bouzin, Caroline; Brouet, Agnes; Wever, Julie de; Jordan, Benedicte F.; Gallez, Bernard; Feron, Olivier

    2007-01-01

    Purpose: To determine whether radiation-induced increases in nitric oxide (NO) production can influence tumor blood flow and improve delivery of Akt-targeting therapeutic DNA lipocomplexes to the tumor. Methods and Materials: The contribution of NO to the endothelial response to radiation was identified using NO synthase (NOS) inhibitors and endothelial NOS (eNOS)-deficient mice. Reporter-encoding plasmids complexed with cationic lipids were used to document the tumor vascular specificity and the efficacy of in vivo lipofection after irradiation. A dominant-negative Akt gene construct was used to evaluate the facilitating effects of radiotherapy on the therapeutic transgene delivery. Results: The abundance of eNOS protein was increased in both irradiated tumor microvessels and endothelial cells, leading to a stimulation of NO release and an associated increase in tumor blood flow. Transgene expression was subsequently improved in the irradiated vs. nonirradiated tumor vasculature. This effect was not apparent in eNOS-deficient mice and could not be reproduced in irradiated cultured endothelial cells. Finally, we combined low-dose radiotherapy with a dominant-negative Akt gene construct and documented synergistic antitumor effects. Conclusions: This study offers a new rationale to combine radiotherapy with gene therapy, by directly exploiting the stimulatory effects of radiation on NO production by tumor endothelial cells. The preferential expression of the transgene in the tumor microvasculature underscores the potential of such an adjuvant strategy to limit the angiogenic response of irradiated tumors

  10. Blood vessel damage correlated with irradiance for in vivo vascular targeted photodynamic therapy

    Science.gov (United States)

    Zhang, Jinde; Tan, Zou; Niu, Xiangyu; Lin, Linsheng; Lin, Huiyun; Li, Buhong

    2016-10-01

    Vascular targeted photodynamic therapy (V-PDT) has been widely utilized for the prevention or treatment of vascular-related diseases, including age-related macular degeneration, port-wine stains and prostate cancer. In order to quantitative assessment the blood vessel damage during V-PDT, nude mice were implanted with Titanium dorsal skin window chambers for in vivo V-PDT studies. For treatments, various irradiances including 50, 75, 100 and 200 mW/cm2 provided by a 532 nm semiconductor laser were performed with the same total light dose of 30 J/cm2 after the mice were intravenously injection of Rose Bengal for 25 mg/Kg body weight. Laser speckle imaging and microscope were used to monitor blood flow dynamics and vessel constriction during and after V-PDT, respectively. The V-PDT induced vessel damages between different groups were compared. The results show that significant difference in blood vessel damage was found between the lower irradiances (50, 75 and 100 mW/cm2) and higher irradiance (200 mW/cm2), and the blood vessel damage induced by V-PDT is positively correlated with irradiance. This study implies that the optimization of irradiance is required for enhancing V-PDT therapeutic efficiency.

  11. The development of uranium foil farication technology utilizing twin roll method for Mo-99 irradiation target

    CERN Document Server

    Kim, C K; Park, H D

    2002-01-01

    MDS Nordion in Canada, occupying about 75% of global supply of Mo-99 isotope, has provided the irradiation target of Mo-99 using the rod-type UAl sub x alloys with HEU(High Enrichment Uranium). ANL (Argonne National Laboratory) through co-operation with BATAN in Indonesia, leading RERTR (Reduced Enrichment for Research and Test Reactors) program substantially for nuclear non-proliferation, has designed and fabricated the annular cylinder of uranium targets, and successfully performed irradiation test, in order to develop the fabrication technology of fission Mo-99 using LEU(Low Enrichment Uranium). As the uranium foils could be fabricated in laboratory scale, not in commercialized scale by hot rolling method due to significant problems in foil quality, productivity and economic efficiency, attention has shifted to the development of new technology. Under these circumstances, the invention of uranium foil fabrication technology utilizing twin-roll casting method in KAERI is found to be able to fabricate LEU or...

  12. SU-C-BRC-05: Monte Carlo Calculations to Establish a Simple Relation of Backscatter Dose Enhancement Around High-Z Dental Alloy to Its Atomic Number

    Energy Technology Data Exchange (ETDEWEB)

    Utsunomiya, S; Kushima, N; Katsura, K; Tanabe, S; Hayakawa, T; Sakai, H; Yamada, T; Takahashi, H; Abe, E; Wada, S; Aoyama, H [Niigata University, Niigata (Japan)

    2016-06-15

    Purpose: To establish a simple relation of backscatter dose enhancement around a high-Z dental alloy in head and neck radiation therapy to its average atomic number based on Monte Carlo calculations. Methods: The PHITS Monte Carlo code was used to calculate dose enhancement, which is quantified by the backscatter dose factor (BSDF). The accuracy of the beam modeling with PHITS was verified by comparing with basic measured data namely PDDs and dose profiles. In the simulation, a high-Z alloy of 1 cm cube was embedded into a tough water phantom irradiated by a 6-MV (nominal) X-ray beam of 10 cm × 10 cm field size of Novalis TX (Brainlab). The ten different materials of high-Z alloys (Al, Ti, Cu, Ag, Au-Pd-Ag, I, Ba, W, Au, Pb) were considered. The accuracy of calculated BSDF was verified by comparing with measured data by Gafchromic EBT3 films placed at from 0 to 10 mm away from a high-Z alloy (Au-Pd-Ag). We derived an approximate equation to determine the relation of BSDF and range of backscatter to average atomic number of high-Z alloy. Results: The calculated BSDF showed excellent agreement with measured one by Gafchromic EBT3 films at from 0 to 10 mm away from the high-Z alloy. We found the simple linear relation of BSDF and range of backscatter to average atomic number of dental alloys. The latter relation was proven by the fact that energy spectrum of backscatter electrons strongly depend on average atomic number. Conclusion: We found a simple relation of backscatter dose enhancement around high-Z alloys to its average atomic number based on Monte Carlo calculations. This work provides a simple and useful method to estimate backscatter dose enhancement from dental alloys and corresponding optimal thickness of dental spacer to prevent mucositis effectively.

  13. Behavior of structural and target materials irradiated in spallation neutron environments

    International Nuclear Information System (INIS)

    Stubbins, J.F.; Wechsler, M.; Borden, M.

    1995-01-01

    This paper describes considerations for selection of structural and target materials for accelerator-driven neutron sources. Due to the operating constraints of proposed accelerator-driven neutron sources, the criteria for selection are different than those commonly applied to fission and fusion systems. Established irradiation performance of various alloy systems is taken into account in the selection criteria. Nevertheless, only limited materials performance data are available which specifically related to neutron energy spectra anticipated for spallation sources

  14. Characterization of third-harmonic target plan irradiance on the National Ignition Facility Beamlet demonstration project

    International Nuclear Information System (INIS)

    Wegner, P.J.; Van Wonterghem, B.M.; Dixit, S.N.; Henesian, M.A.; Barker, C.E.; Thompson, C.E.; Seppala, L.G.; Caird, J.A.

    1997-01-01

    The Beamlet laser is a single-aperture prototype for the National Ignition Facility (NIF). We have recently installed and activated a 55 m 3 vacuum vessel and associated diagnostic package at the output of the Beamlet that we are using to characterize target plane irradiance at high power. Measurements obtained both with and without a kinoform diffractive optic are reported. Dependences on critical laser parameters including output power, spatial filtering, and wavefront correction are discussed and compared with simulations

  15. Behavior of structural and target materials irradiated in spallation neutron environments

    Energy Technology Data Exchange (ETDEWEB)

    Stubbins, J.F. [Univ. of Illinois, Urbana, IL (United States); Wechsler, M. [North Carolina State Univ., Raleigh, NC (United States); Borden, M. [Los Alamos National Laboratory, NM (United States)] [and others

    1995-10-01

    This paper describes considerations for selection of structural and target materials for accelerator-driven neutron sources. Due to the operating constraints of proposed accelerator-driven neutron sources, the criteria for selection are different than those commonly applied to fission and fusion systems. Established irradiation performance of various alloy systems is taken into account in the selection criteria. Nevertheless, only limited materials performance data are available which specifically related to neutron energy spectra anticipated for spallation sources.

  16. High-Z Nanoparticle/Polymer Nanocomposites for Gamma-Ray Scintillation Detectors

    Science.gov (United States)

    Liu, Chao

    An affordable and reliable solution for spectroscopic gamma-ray detection has long been sought after due to the needs from research, defense, and medical applications. Scintillators resolve gamma energy by proportionally converting a single high-energy photon into a number of photomultiplier-tube-detectable low-energy photons, which is considered a more affordable solution for general purposes compared to the delicate semiconductor detectors. An ideal scintillator should simultaneously exhibit the following characteristics: 1) high atomic number (Z) for high gamma stopping power and photoelectron production; 2) high light yield since the energy resolution is inversely proportional to the square root of light yield; 3) short emission decay lifetime; and 4) low cost and scalable production. However, commercial scintillators made from either inorganic single crystals or plastics fail to satisfy all requirements due to their intrinsic material properties and fabrication limitations. The concept of adding high-Z constituents into plastic scintillators to harness high Z, low cost, and fast emission in the resulting nanocomposite scintillators is not new in and of itself. Attempts have been made by adding organometallics, quantum dots, and scintillation nanocrystals into the plastic matrix. High-Z organometallics have long been used to improve the Z of plastic scintillators; however, their strong spin-orbit coupling effect entails careful triplet energy matching using expensive triplet emitters to avoid severe quenching of the light yield. On the other hand, reported quantum dot- and nanocrystal-polymer nanocomposites suffer from moderate Z and high optical loss due to aggregation and self-absorption at loadings higher than 10 wt%, limiting their potential for practical application. This dissertation strives to improve the performance of nanoparticle-based nanocomposite scintillators. One focus is to synthesize transparent nanocomposites with higher loadings of high-Z

  17. The target theory applied to the analysis of irradiation damages in organic detectors

    International Nuclear Information System (INIS)

    Mesquita, Carlos Henrique de

    2005-01-01

    The Target Theory was used to explain the radiation damage in samples containing 1% (g//L) of 2,5-diphenyl-oxazolyl (PPO) diluted in toluene and irradiated with 60 Co (1.8 Gy/s). The survival molecules of irradiated PPO obeys the bi-exponential mathematical model [74.3 x exp(-D/104.3) + 25.7 x exp(-D/800,0)]. It indicates that 74.3% of the molecules decay with D37=104.3 kGy and 25.7% decay with D37=800 kGy. From the Target Theory it was inferred the energies involved in the irradiation damages which were 0.239 ± 0.031 eV (G=418.4 ± 54.1. damages/100 eV) and 1.83 ± 0.30 eV (54.5 ± 8.9 damages/100 eV). The diameter of PPO molecule estimated from the Target Theory is in the interval of 45.5 to 64.9 angstrom. (author)

  18. Recovery and purification of nickel-63 from HFIR-irradiated targets

    International Nuclear Information System (INIS)

    Williams, D.F.; O'Kelley, G.D.; Knauer, J.B.; Porter, C.E.; Wiggins, J.T.

    1993-06-01

    The production of large quantities of high-specific-activity 63 Ni (>10 Ci/g) requires both a highly enriched 62 Ni target and a long irradiation period at high neutron flux. Trace impurities in the nickel and associated target materials are also activated and account for a significant fraction of the discharged activity and essentially all of the gamma activity. While most of these undesirable activation products can be removed as chloride complexes during anion exchange, chromium, present at 51 Cr, and scandium, present as 46 Sc, are exceptions and require additional processing to achieve the desired purity. Optimized flowsheets are discussed based upon the current development and production experience

  19. Lateral propagation of fast electrons at the laser-irradiated target surfaces

    International Nuclear Information System (INIS)

    Li, Y T; Lin, X X; Liu, B C; Du, F; Wang, S J; Li, C; Zhou, M L; Zhang, L; Liu, X; Wang, J; Liu, X L; Chen, L M; Wang, Z H; Ma, J L; Wei, Z Y; Zhang, J; Liu, F; Liu, F

    2010-01-01

    Lateral propagation of fast electrons at the target surfaces irradiated by femtosecond intense laser pulses is measured by k α x-ray imaging technique when a preplasma is presented. An annular halo surrounding a bright spot is observed in the x-ray images when the scale length of the electron density is large. For an incidence angle of 70 0 the x-ray images show a non-symmetrical distribution peaked to the laser propagation direction. The x-ray photons in the halo are mainly excited by the fast electrons that flow in the preplasma when their paths intersect the high density regions near the target surface.

  20. The disintegration and vaporization of plastic targets irradiated by high-power laser pulses

    International Nuclear Information System (INIS)

    Greig, J.R.; Pechacek, R.E.

    1977-01-01

    We have studied the disintegration of polyethylene and polystyrene targets irradiated by 100-J 40-nsec Nd/glass laser pulses. At power densities of approximately-less-than10 12 W/cm 2 relatively massive targets (6 x 10 -5 to 5 x 10 -4 cm 3 ) are totally disintegrated to produce finely divided target material and un-ionized vapor. Both the size of the target and the presence or absence of a laser prepulse strongly influence the proportions of finely divided target material and un-ionized vapor, especially within the first few microseconds after peak laser power. This disintegration is always preceded by the emission of a hot fully ionized plasma, but only 1% of the target material is contained in the hot plasma. Typically, (1--3) x 10 19 atoms of un-ionized vapor are released as a slowly expanding (vapprox.10 5 cm/sec) cold dense gas cloud (n/sub o/>10 19 cm -3 ) surrounding the initial target position. This cloud of target material has subsequently been heated by absorption of a 300-J 100-nsec CO 2 laser pulse to produce an approximately fully ionized plasma

  1. In vitro and in vivo ion beam targeted micro-irradiation for radiobiology

    International Nuclear Information System (INIS)

    Vianna, Francois

    2014-01-01

    The main goal of radiobiology is to understand the effects of ionizing radiations on the living. These past decades, ion microbeams have shown to be important tools to study for example the effects of low dose exposure, or the bystander effect. Since 2003, the CENBG has been equipped with a system to perform targeted micro-irradiation of living samples. Recently, microbeams applications on this subject have diversified and the study of DNA repair mechanisms at the cellular and multicellular scales, in vitro and in vivo, has become possible thanks to important evolutions of fluorescence imaging techniques and cellular biology. To take into account these new approaches, the CENBG micro-irradiation beamline has been entirely redesigned and rebuilt to implement new features and to improve the existing ones. My PhD objectives were i) commissioning the facility, ii) characterizing the system on track etch detectors, and on living samples, iii) implementing protocols to perform targeted irradiations of living samples with a con-trolled delivered dose, at the cellular and multicellular scales, and to visualize the early consequences online, iv) modelling these irradiations to explain the biological results using the calculated physical data. The work of these past years has allowed us i) to measure the performances of our system: a beam spot size of about 2 μm and a targeting accuracy of ± 2 μm, and to develop ion detection systems for an absolute delivered dose control, ii) to create highly localized radiation-induced DNA damages and to see online the recruitment of DNA repair proteins, iii) to apply these protocols to generate radiation-induced DNA damages in vivo inside a multicellular organism at the embryonic stage: Caenorhabditis elegans. These results have opened up many perspectives on the study of the interaction between ionizing radiations and the living, at the cellular and multicellular scales, in vitro and in vivo. (author) [fr

  2. Imaging of high-Z material for nuclear contraband detection with a minimal prototype of a muon tomography station based on GEM detectors

    Energy Technology Data Exchange (ETDEWEB)

    Gnanvo, Kondo, E-mail: kgnanvo@fit.edu [Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States); Grasso, Leonard V.; Hohlmann, Marcus; Locke, Judson B.; Quintero, Amilkar [Department of Physics and Space Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States); Mitra, Debasis [Department of Computer Sciences, Florida Institute of Technology, Melbourne, FL 32901 (United States)

    2011-10-01

    Muon Tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons in matter is a promising technique for detecting heavily shielded high-Z radioactive materials (U, Pu) in cargo or vehicles. The technique uses the deflection of cosmic ray muons in matter to perform tomographic imaging of high-Z material inside a probed volume. A Muon Tomography Station (MTS) requires position-sensitive detectors with high spatial resolution for optimal tracking of incoming and outgoing cosmic ray muons. Micro Pattern Gaseous Detector (MPGD) technologies such as Gas Electron Multiplier (GEM) detectors are excellent candidates for this application. We have built and operated a minimal MTS prototype based on 30 cmx30 cm GEM detectors for probing targets with various Z values inside the MTS volume. We report the first successful detection and imaging of medium-Z and high-Z targets of small volumes ({approx}0.03 L) using GEM-based Muon Tomography.

  3. Imaging of high-Z material for nuclear contraband detection with a minimal prototype of a muon tomography station based on GEM detectors

    International Nuclear Information System (INIS)

    Gnanvo, Kondo; Grasso, Leonard V.; Hohlmann, Marcus; Locke, Judson B.; Quintero, Amilkar; Mitra, Debasis

    2011-01-01

    Muon Tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons in matter is a promising technique for detecting heavily shielded high-Z radioactive materials (U, Pu) in cargo or vehicles. The technique uses the deflection of cosmic ray muons in matter to perform tomographic imaging of high-Z material inside a probed volume. A Muon Tomography Station (MTS) requires position-sensitive detectors with high spatial resolution for optimal tracking of incoming and outgoing cosmic ray muons. Micro Pattern Gaseous Detector (MPGD) technologies such as Gas Electron Multiplier (GEM) detectors are excellent candidates for this application. We have built and operated a minimal MTS prototype based on 30 cmx30 cm GEM detectors for probing targets with various Z values inside the MTS volume. We report the first successful detection and imaging of medium-Z and high-Z targets of small volumes (∼0.03 L) using GEM-based Muon Tomography.

  4. Negative pressure and spallation in graphite targets under nano- and picosecond laser irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Belikov, R S; Khishchenko, K V [Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow (Russian Federation); Krasyuk, I K; Semenov, A Yu; Stuchebryukhov, I A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation); Rinecker, T; Schoenlein, A [Goethe University Frankfurt am Main (Germany); Rosmej, O N [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Germany, 64291 Darmstadt, Planckstraße, 1 (Germany); Tomut, M [Technische Universität Darmstadt, Germany, 64289 Darmstadt, Karolinenplatz, 5 (Germany)

    2015-05-31

    We present the results of experiments on the spallation phenomena in graphite targets under shock-wave nano- and picosecond irradiation, which have been performed on Kamerton-T (GPI, Moscow, Russia) and PHELIX (GSI, Darmstadt, Germany) laser facilities. In the range of the strain rates of 10{sup 6} – 10{sup 7} s{sup -1}, the data on the dynamic mechanical strength of the material at rapure (spallation) have been for the first time obtained. With a maximal strain rate of 1.4 × 10{sup 7} s{sup -1}, the spall strength of 2.1 GPa is obtained, which constitutes 64% of the theoretical ultimate tensile strength of graphite. The effect of spallation is observed not only on the rear side of the target, but also on its irradiated (front) surface. With the use of optical and scanning electron microscopes, the morphology of the front and rear surfaces of the targets is studied. By means of Raman scattering of light, the graphite structure both on the target front surface under laser exposure and on its rear side in the spall zone is investigated. A comparison of the dynamic strength of graphite and synthetic diamond is performed. (extreme light fields and their applications)

  5. High-energy, twelve-channel laser facility (DEFIN) for spherical irradiation of thermonuclear targets

    International Nuclear Information System (INIS)

    Basov, N.G.; Danilov, A.E.; Krokhin, O.N.; Kruglov, B.V.; Mikhailov, Yu.A.; Sklizkov, G.V.; Fedotov, S.I.; Fedorov, A.N.

    This paper describes a high-energy, twelve-channel laser facility (DELFIN) intended for high-temperature heating of thermonuclear targets with spherical symmetry. The facility includes a neodymium-glass laser with the ultimate radiation energy of 10 kJ, a pulse length of approximately 10 -10 to 10 -9 s, beam divergence of 5 x 10 -4 radians, a vacuum chamber in which laser radiation interacts with the plasma, and a system of diagnostic instrumentation for the observation of laser beam and plasma parameters. Described are the optical scheme and construction details of the laser facility. Presented is an analysis of focusing schemes for target irradiation and described is the focusing scheme of the DELFIN facility, which is capable of attaining a high degree of spherical symmetry in irradiating targets with maximum beam intensity at the target surface of approximately 10 15 W/cm 2 . This paper examines the most important problems connected with the physical investigations of thermonuclear laser plasma and the basic diagnostic problems involved in their solution

  6. Compaction and sintering of nickel powder used encapsulation of irradiation targets

    Energy Technology Data Exchange (ETDEWEB)

    Miyano, Rosana S.L.; Guimaraes, Raquel R.F.L.; Rossi, Jesualdo L., E-mail: rosatac@gmail.com, E-mail: raquel.lucchesi@icloud.com, E-mail: jelrossi@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (CCTM/IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Centro de Ciencia e Tecnologia de Materiais; Wendhausen, Paulo A.P.; Evangelista, Leandro L., E-mail: paulo.wendhausen@ufsc.br, E-mail: leandro.materiais@gmail.com [Universidade Federal de Santa Catarina (UFSC), Florianopolis, SC (Brazil). Laboratorio de Materiais

    2015-07-01

    The objective of this study was to develop an alternative way to produce targets for irradiation containing uranium, for the pair of {sup 99}Mo production {sup 99m}Tc radionuclide. These targets were obtained by powder metallurgy, the compact serving as means for encapsulation a uranium cylinder to be irradiated. The targets were compacted in an axial hydraulic press applying different pressures up to 800 MPa. The sintering temperature was 600 °C in hydrogen atmosphere and it was used two sintering cycles, one for 4 h and the for 4 h plus 8 h time. The nickel powder was of high purity, that in order to provide the sealing of the fissile content within the compacted. The bulk density of compacted was evaluated by the method geometric. The porosity was measured by mercury porosimetry technique. The microstructure was investigated by optical microscopy. The results obtained with sintering powders involving confirm the feasibility of achieving a casing for uranium targets. (author)

  7. Study of an automatized experimental device for the irradiation of a radioactive target

    International Nuclear Information System (INIS)

    Claverie, G.

    1996-01-01

    In order to solve the enigma of solar neutrinos, a team of physicians of the nuclear research center of Bordeaux-Gradignan and of the center of nuclear spectroscopy and mass spectroscopy of Orsay (France) decided to measure again the cross section of the beryllium-proton nuclear reaction at the lowest possible energies. This measurement requires the design of an automatized experimental device to irradiate in a specific way a beryllium target with an accelerated proton beam. The aim of this work is the study of such a device for an energy range of 800 to 300 KeV. This device comprises a particle multi-detector and a shutter for the irradiation of the target and the counting of the reaction products according to a programmable time sequence. The advantage of this setup is to allow an important bombardment of the target and to ensure its cooling. This device is automatically controlled thanks to a micro-controller, actuators (step motors and electrostatic deflector). It includes some beam diagnosis elements controlled by step motors and a target temperature monitoring system controlling a safety valve. The management of the experiment cell vacuum has led to the design of a vacuum monitor allowing the precise follow up of the vacuum and the control of the safety valves of the device. The nuclear instrumentation necessary to be implemented for this measurement is also presented. (J.S.)

  8. Gamma Knife irradiation method based on dosimetric controls to target small areas in rat brains

    International Nuclear Information System (INIS)

    Constanzo, Julie; Paquette, Benoit; Charest, Gabriel; Masson-Côté, Laurence; Guillot, Mathieu

    2015-01-01

    Purpose: Targeted and whole-brain irradiation in humans can result in significant side effects causing decreased patient quality of life. To adequately investigate structural and functional alterations after stereotactic radiosurgery, preclinical studies are needed. The purpose of this work is to establish a robust standardized method of targeted irradiation on small regions of the rat brain. Methods: Euthanized male Fischer rats were imaged in a stereotactic bed, by computed tomography (CT), to estimate positioning variations relative to the bregma skull reference point. Using a rat brain atlas and the stereotactic bregma coordinates obtained from CT images, different regions of the brain were delimited and a treatment plan was generated. A single isocenter treatment plan delivering ≥100 Gy in 100% of the target volume was produced by Leksell GammaPlan using the 4 mm diameter collimator of sectors 4, 5, 7, and 8 of the Gamma Knife unit. Impact of positioning deviations of the rat brain on dose deposition was simulated by GammaPlan and validated with dosimetric measurements. Results: The authors’ results showed that 90% of the target volume received 100 ± 8 Gy and the maximum of deposited dose was 125 ± 0.7 Gy, which corresponds to an excellent relative standard deviation of 0.6%. This dose deposition calculated with GammaPlan was validated with dosimetric films resulting in a dose-profile agreement within 5%, both in X- and Z-axes. Conclusions: The authors’ results demonstrate the feasibility of standardizing the irradiation procedure of a small volume in the rat brain using a Gamma Knife

  9. Pressure control of a proton beam-irradiated water target through an internal flow channel-induced thermosyphon.

    Science.gov (United States)

    Hong, Bong Hwan; Jung, In Su

    2017-07-01

    A water target was designed to enhance cooling efficiency using a thermosyphon, which is a system that uses natural convection to induce heat exchange. Two water targets were fabricated: a square target without any flow channel and a target with a flow channel design to induce a thermosyphon mechanism. These two targets had the same internal volume of 8 ml. First, visualization experiments were performed to observe the internal flow by natural convection. Subsequently, an experiment was conducted to compare the cooling performance of both water targets by measuring the temperature and pressure. A 30-MeV proton beam with a beam current of 20 μA was used to irradiate both targets. Consequently, the target with an internal flow channel had a lower mean temperature and a 50% pressure drop compared to the target without a flow channel during proton beam irradiation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Microwave radiation mechanism in a pulse-laser-irradiated Cu foil target revisited

    International Nuclear Information System (INIS)

    Chen Ziyu; Li Jianfeng; Li Jun; Peng Qixian

    2011-01-01

    The microwave radiation mechanism in a Cu-based foil target irradiated by an intense laser pulse has been investigated. Microwave emission in the frequency range 0.5-4 GHz has been observed from a 200 ps laser pulse of intensity about 10 12 W cm -2 normally incident on the target surface. The total microwave power and energy emitted from the interaction were found to be about 0.4 W and 2 nJ, respectively, corresponding to an efficiency of coupling laser energy to microwave energy of 2x10 -8 . The result agrees well with quadrupole radiation calculated based on a circuit model of a laser plasma, which indicates that the radiative process can be explained by magnetic dipole or electric quadrupole radiation from the laser-produced symmetric poloidal current distribution at the plasma-target interface.

  11. Microwave radiation mechanism in a pulse-laser-irradiated Cu foil target revisited

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ziyu; Li Jianfeng; Li Jun; Peng Qixian, E-mail: ziyuch@gmail.com [Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang 621900 (China)

    2011-05-01

    The microwave radiation mechanism in a Cu-based foil target irradiated by an intense laser pulse has been investigated. Microwave emission in the frequency range 0.5-4 GHz has been observed from a 200 ps laser pulse of intensity about 10{sup 12} W cm{sup -2} normally incident on the target surface. The total microwave power and energy emitted from the interaction were found to be about 0.4 W and 2 nJ, respectively, corresponding to an efficiency of coupling laser energy to microwave energy of 2x10{sup -8}. The result agrees well with quadrupole radiation calculated based on a circuit model of a laser plasma, which indicates that the radiative process can be explained by magnetic dipole or electric quadrupole radiation from the laser-produced symmetric poloidal current distribution at the plasma-target interface.

  12. Spatial distribution of moderated neutrons along a Pb target irradiated by high-energy protons

    International Nuclear Information System (INIS)

    Fragopoulou, M.; Manolopoulou, M.; Stoulos, S.; Brandt, R.; Westmeier, W.; Kulakov, B.A.; Krivopustov, M.I.; Sosnin, A.N.; Debeauvais, M.; Adloff, J.C.; Zamani Valasiadou, M.

    2006-01-01

    High-energy protons in the range of 0.5-7.4 GeV have irradiated an extended Pb target covered with a paraffin moderator. The moderator was used in order to shift the hard Pb spallation neutron spectrum to lower energies and to increase the transmutation efficiency via (n,γ) reactions. Neutron distributions along and inside the paraffin moderator were measured. An analysis of the experimental results was performed based on particle production by high-energy interactions with heavy targets and neutron spectrum shifting by the paraffin. Conclusions about the spallation neutron production in the target and moderation through the paraffin are presented. The study of the total neutron fluence on the moderator surface as a function of the proton beam energy shows that neutron cost is improved up to 1 GeV. For higher proton beam energies it remains constant with a tendency to decline

  13. Separation of protactinum, actinium, and other radionuclides from proton irradiated thorium target

    Science.gov (United States)

    Fassbender, Michael E.; Radchenko, Valery

    2018-04-24

    Protactinium, actinium, radium, radiolanthanides and other radionuclide fission products were separated and recovered from a proton-irradiated thorium target. The target was dissolved in concentrated HCl, which formed anionic complexes of protactinium but not with thorium, actinium, radium, or radiolanthanides. Protactinium was separated from soluble thorium by loading a concentrated HCl solution of the target onto a column of strongly basic anion exchanger resin and eluting with concentrated HCl. Actinium, radium and radiolanthanides elute with thorium. The protactinium that is retained on the column, along with other radionuclides, is eluted may subsequently treated to remove radionuclide impurities to afford a fraction of substantially pure protactinium. The eluate with the soluble thorium, actinium, radium and radiolanthanides may be subjected to treatment with citric acid to form anionic thorium, loaded onto a cationic exchanger resin, and eluted. Actinium, radium and radiolanthanides that are retained can be subjected to extraction chromatography to separate the actinium from the radium and from the radio lanthanides.

  14. Post-Irradiation Properties of Candidate Materials for High-Power Targets

    International Nuclear Information System (INIS)

    Kirk, H.G.; Ludewig, H.; Mausner, L.F.; Simos, N.; Thieberger, P.; Brookhaven; Hayato, Y.; Yoshimura, K.; McDonald, K.T.; Sheppard, J.; Trung, L.P.

    2006-01-01

    The desire of the high-energy-physics community for more intense secondary particle beams motivates the development of multi-megawatt, pulsed proton sources. The targets needed to produce these secondary particle beams must be sufficiently robust to withstand the intense pressure waves arising from the high peak-energy deposition which an intense pulsed beam will deliver. In addition, the materials used for the targets must continue to perform in a severe radiation environment. The effect of the beam-induced pressure waves can be mitigated by use of target materials with high-yield strength and/or low coefficient of thermal expansion (CTE) [1, 2, 3]. We report here first results of an expanded study of the effects of irradiation on several additional candidate materials with high strength (AlBeMet, beryllium, Ti-V6-Al4) or low CTE (a carbon-carbon composite, a new Toyota ''gum'' metal alloy [4], Super-Invar)

  15. Laser irradiation of disk targets at 0.53 μm wavelength

    International Nuclear Information System (INIS)

    Mead, W.C.; Campbell, E.M.; Estabrook, K.G.

    1981-01-01

    We present results and analysis for laser-irradiations of Be, CH, Ti, and Au disk targets with 0.53 μm light in 3 to 35 J, 600 ps pulses, at nominal intensities from 3 x 10 13 to approx. 4 x 10 15 W/cm 2 . The measured absorptions are higher than observed in similar 1.06 μm irradiations, and are largely consistent with modeling which shows the importance of inverse bremsstrahlung and Brillouin scattering. Observed red-shifted back-reflected light shows that Brillouin is operating at low to moderate levels. The measured fluxes of multi-keV x-rays indicate low hot-electron fractions, with temperatures which are consistent with resonance absorption. Measurements show efficient conversion of absorbed light into sub-keV x-rays, with time-, angular-, and spatial-emission distributions which are generally consistent with non-LTE modeling using inhibited thermal electron transport

  16. U-target irradiation at FRM II aiming the production of Mo-99 - A feasibility study

    International Nuclear Information System (INIS)

    Gerstenberg, H.; Mueller, C.; Neuhaus, I.; Roehrmoser, A.

    2010-01-01

    Following the shortage in radioisotope availability the Technische Unversitaet Muenchen and the Belgian Institut National des Radioelements conducted a common study on the suitability of the FRM II reactor for the generation of Mo-99 as a fission product. A suitable irradiation channel was determined and neutronic calculations resulted in sufficiently high neutron flux densities to make FRM II a promising candidate for Mo-99 production. In addition the feasibility study provides thermohydraulic calculations as input for the design and integration of the additional cooling circuit into the existing heat removal systems of FRM II. The required in-house processes for a regular uranium target irradiation programme have been defined and necessary upgrades identified. Finally the required investment cost was estimated and a possible time schedule was given. (author)

  17. Reduced cost design of liquid lithium target for international fusion material irradiation facility (IFMIF)

    International Nuclear Information System (INIS)

    Nakamura, Hiroo; Ida, Mizuho; Sugimoto, Masayoshi; Takeuchi, Hiroshi; Yutani, Toshiaki

    2001-01-01

    The International Fusion Materials Irradiation Facility (IFMIF) is being jointly planned to provide an accelerator-based D-Li neutron source to produce intense high energy neutrons (2 MW/m 2 ) up to 200 dpa and a sufficient irradiation volume (500 cm 3 ) for testing the candidate materials and components up to about a full lifetime of their anticipated use in ITER and DEMO. To realize such a condition, 40 MeV deuteron beam with a current of 250 mA is injected into high speed liquid lithium flow with a speed of 20 m/s. Following Conceptual Design Activity (1995-1998), a design study with focus on cost reduction without changing its original mission has been done in 1999. The following major changes to the CAD target design have been considered in the study and included in the new design: i) number of the Li target has been changed from 2 to 1, ii) spare of impurity traps of the Li loop was removed although the spare will be stored in a laboratory for quick exchange, iii) building volume was reduced via design changes in lithium loop length. This paper describes the reduced cost design of the lithium target system and recent status of Key Element Technology activities. (author)

  18. Mono-energetic ions emission by nanosecond laser solid target irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Muoio, A., E-mail: Annamaria.Muoio@lns.infn.it [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina, Viale F.S. D’Alcontres 31, 98166 Messina (Italy); Tudisco, S. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Altana, C. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Dipartimento di Fisica e Astronomia, Università degli Studi di Catania, Via S. Sofia 64, 95123 Catania (Italy); Lanzalone, G. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Università degli Studi di Enna “Kore”, Via delle Olimpiadi, 94100 Enna (Italy); Mascali, D.; Cirrone, G.A.P.; Schillaci, F. [Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali del Sud, Via S. Sofia 62, 95123 Catania (Italy); Trifirò, A. [Dipartimento di Fisica e Scienze della Terra, Università degli Studi di Messina, Viale F.S. D’Alcontres 31, 98166 Messina (Italy); Sezione INFN, Catania (Italy)

    2016-09-01

    An experimental campaign aiming to investigate the acceleration mechanisms through laser–matter interaction in nanosecond domain has been carried out at the LENS (Laser Energy for Nuclear Science) laboratory of INFN-LNS, Catania. Pure Al targets were irradiated by 6 ns laser pulses at different pumping energies, up to 2 J. Advanced diagnostics tools were used to characterize the plasma plume and ion production. We show the preliminary results of this experimental campaign, and especially the ones showing the production of multicharged ions having very narrow energy spreads.

  19. Effects of buried high-Z layers on fast electron propagation

    International Nuclear Information System (INIS)

    Yang, Xiaohu; Zhuo, Hongbin; Ma, Yanyun; Shao, Fuqiu; Xu, Han; Yin Yan; Borghesi, M.

    2014-01-01

    The transport through high density plasmas of relativistic electron beams generated by ultra-intense laser-plasma interaction has potential applications in laser-driven ion acceleration and in the fast igniter scheme for inertial confinement fusion. By extending a prior model [A.R. Bell, J.R. Davies, S.M. Guerin, Phys. Rev. E 58, 2471 (1998)], the magnetic field generated during the transport of a fast electron beam driven by an ultra-intense laser in a solid target is derived analytically and applied to estimate the effect of such field on fast electron propagation through a buried high-Z layer in a lower-Z target. It is found that the effect gets weaker with the increase of the depth of the buried layer, the divergence of the fast electrons, and the laser intensity, indicating that magnetic field effects on the fast electron divergence as measured from K a X-ray emission may need to be considered for moderate laser intensities. On the basis of the calculations, some considerations are made on how one can mitigate the effect of the magnetic field generated at the interface. (authors)

  20. LPI studies with grazing incidence irradiation at the Nike laser

    Science.gov (United States)

    Weaver, J.; Kehne, D.; Schmitt, A.; Obenschain, S.; Serlin, V.; Oh, J.; Lehmberg, R.; Seely, J.

    2013-10-01

    Studies of laser plasma instabilities (LPI) at the Nike laser facility at NRL have previously concentrated on planar targets irradiated with their surface normal aligned to the central axis of the laser. Shots with planar targets rotated up 60° to the laser have shown changes in thresholds for the two-plasmon decay instability and stimulated Raman scattering near the quarter critical region. In the case of rotated low-Z targets, spectra were observed to shift to lower wavelength and were substantially stronger in the visible and ultraviolet spectral ranges. The low-Z target data show growth at an incident intensity slightly below (~30%) the threshold values observed at normal incidence. A rapid rise in signal level over the same laser intensities was also observed in the hard x-ray data which serve as an overall indicator of LPI activity. Shots with rotated planar high-Z targets showed that the visible and ultraviolet emissions dropped significantly when compared to low-Z targets in the same geometry. This presentation will include results from upcoming experiments to determine the LPI signal for low-Z, high-Z, and high-Z coated targets at lower laser intensities for several angles of target rotation. Shots with widely separated laser beams are also planned to explore cross beam energy transport at Nike. Work supported by DoE/NNSA.

  1. Ultra-high vacuum target assembly for charged particle irradiations in the materials research field

    International Nuclear Information System (INIS)

    Bressers, J.; Cassanelli, G.; Cat, R. de; Kohnen, H.; Gherardi, G.

    1978-01-01

    A target assembly designed for ion irradiation and ion implantation experiments on different particle accelerators is described. It consists of a target chamber separated from the beam line by a thin metal window, thus allowing implantations to be carried out under ultra-high vacuum conditions. Homogeneous in-depth distribution of the implanted ion species is realized by rotating the target about an axis perpendicular to the ion beam (rocking). The target holder is driven by means of a stepping motor with a constant step angle and a rocking device controller containing the required rocking angle-dwell time relation. Ion beam homogeneity over a sufficiently large target area is arrived at by transforming the Gaussian beam intensity profile into a flat beam intensity distribution by means of an electrostatic ring lens. The beam intensity profile is monitored by means of a specially designed ion beam monitor based on the Nipkov disc principle. A toroidal beam current monitoring transformer continuously measures the total beam current. Beam scanners and current measuring collimators complete the beam analysing equipment

  2. High-speed photographic methods for compression dynamics investigation of laser irradiated shell target

    International Nuclear Information System (INIS)

    Basov, N.G.; Kologrivov, A.A.; Krokhin, O.N.; Rupasov, A.A.; Shikanov, A.S.

    1979-01-01

    Three methods are described for a high-speed diagnostics of compression dynamics of shell targets being spherically laser-heated on the installation ''Kal'mar''. The first method is based on the direct investigation of the space-time evolution of the critical-density region for Nd-laser emission (N sub(e) asymptotically equals 10 21 I/cm 3 ) by means of the streak photography of plasma image in the second-harmonic light. The second method involves investigation of time evolution of the second-harmonic spectral distribution by means of a spectrograph coupled with a streak camera. The use of a special laser pulse with two time-distributed intensity maxima for the irradiation of shell targets, and the analysis of the obtained X-ray pin-hole pictures constitute the basis of the third method. (author)

  3. Wide range scaling laws for radiation driven shock speed, wall albedo and ablation parameters for high-Z materials

    Science.gov (United States)

    Mishra, Gaurav; Ghosh, Karabi; Ray, Aditi; Gupta, N. K.

    2018-06-01

    Radiation hydrodynamic (RHD) simulations for four different potential high-Z hohlraum materials, namely Tungsten (W), Gold (Au), Lead (Pb), and Uranium (U) are performed in order to investigate their performance with respect to x-ray absorption, re-emission and ablation properties, when irradiated by constant temperature drives. A universal functional form is derived for estimating time dependent wall albedo for high-Z materials. Among the high-Z materials studied, it is observed that for a fixed simulation time the albedo is maximum for Au below 250 eV, whereas it is maximum for U above 250 eV. New scaling laws for shock speed vs drive temperature, applicable over a wide temperature range of 100 eV to 500 eV, are proposed based on the physics of x-ray driven stationary ablation. The resulting scaling relation for a reference material Aluminium (Al), shows good agreement with that of Kauffman's power law for temperatures ranging from 100 eV to 275 eV. New scaling relations are also obtained for temperature dependent mass ablation rate and ablation pressure, through RHD simulation. Finally, our study reveals that for temperatures above 250 eV, U serves as a better hohlraum material since it offers maximum re-emission for x-rays along with comparable mass ablation rate. Nevertheless, traditional choice, Au works well for temperatures below 250 eV. Besides inertial confinement fusion (ICF), the new scaling relations may find its application in view-factor codes, which generally ignore atomic physics calculations of opacities and emissivities, details of laser-plasma interaction and hydrodynamic motions.

  4. X-ray conversion efficiency of high-Z hohlraum wall materials for indirect drive ignition

    International Nuclear Information System (INIS)

    Dewald, E. L.; Rosen, M.; Glenzer, S. H.; Suter, L. J.; Neumayer, P.; Landen, O. L.; Girard, F.; Jadaud, J. P.; Wagon, F.; Huser, G.; Schein, J.; Constantin, C.

    2008-01-01

    The conversion efficiency of 351 nm laser light to soft x rays (0.1-5 keV) was measured for Au, U, and high Z mixture ''cocktails'' used as hohlraum wall materials in indirect drive fusion experiments. For the spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates are employed to achieve constant and uniform laser intensities of 10 14 and 10 15 W/cm 2 over the target surface that are relevant for the future ignition experiments at the National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Nucl. Fusion 44, 228 (2004)]. The absolute time and spectrally resolved radiation flux is measured with a multichannel soft x-ray power diagnostic. The conversion efficiency is then calculated by dividing the measured x-ray power by the incident laser power from which the measured laser backscattering losses are subtracted. After ∼0.5 ns, the time resolved x-ray conversion efficiency reaches a slowly increasing plateau of 95% at 10 14 W/cm 2 laser intensity and of 80% at 10 15 W/cm 2 . The M-band flux (2-5 keV) is negligible at 10 14 W/cm 2 reaching ∼1% of the total x-ray flux for all target materials. In contrast, the M-band flux is significant and depends on the target material at 10 15 W/cm 2 laser intensity, reaching values between 10% of the total flux for U and 27% for Au. LASNEX simulations [G. B. Zimmerman and W. L. Kruer, Comm. Plasma Phys. Contr. Fusion 2, 51 (1975)] show good agreement in conversion efficiency and radiated spectra with data when using XSN atomic physics model and a flux limiter of 0.15, but they underestimate the generated M-band flux.

  5. X-ray Conversion Efficiency of high-Z hohlraum wall materials for indirect drive ignition

    International Nuclear Information System (INIS)

    Dewald, E.; Rosen, M.; Glenzer, S.H.; Suter, L.J.; Girard, F.; Jadaud, J.P.; Schein, J.; Constantin, C.G.; Neumayer, P.; Landen, O.

    2008-01-01

    We measure the conversion efficiency of 351 nm laser light to soft x-rays (0.1-5 keV) for Au, U and high Z mixtures 'cocktails' used for hohlraum wall materials in indirect drive ICF. We use spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates to achieve constant and uniform laser intensities of 10 14 and 10 15 W/cm 2 over the target surface that are relevant for the future ignition experiments on NIF. The absolute time and spectrally-resolved radiation flux is measured with a multichannel soft x-ray power diagnostic. The conversion efficiency is then calculated by dividing the measured x-ray power by the incident laser power from which the measured laser backscattering losses is subtracted. After ∼0.5 ns, the time resolved x-ray conversion efficiency reaches a slowly increasing plateau of 95% at 10 14 W/cm 2 laser intensity and of 80% at 10 15 W/cm 2 . The M-band flux (2-5 keV) is negligible at 10 14 W/cm 2 reaching ∼1% of the total x-ray flux for all target materials. In contrast, the M-band flux is significant and depends on the target material at 10 15 W/cm 2 laser intensity, reaching values between 10% of the total flux for U and 27% for Au. Our LASNEX simulations show good agreement in conversion efficiency and radiated spectra with data when using XSN atomic physics model and a flux limiter of 0.15, but they underestimate the generated M-band flux

  6. Low-Dose Irradiation Enhances Gene Targeting in Human Pluripotent Stem Cells.

    Science.gov (United States)

    Hatada, Seigo; Subramanian, Aparna; Mandefro, Berhan; Ren, Songyang; Kim, Ho Won; Tang, Jie; Funari, Vincent; Baloh, Robert H; Sareen, Dhruv; Arumugaswami, Vaithilingaraja; Svendsen, Clive N

    2015-09-01

    Human pluripotent stem cells (hPSCs) are now being used for both disease modeling and cell therapy; however, efficient homologous recombination (HR) is often crucial to develop isogenic control or reporter lines. We showed that limited low-dose irradiation (LDI) using either γ-ray or x-ray exposure (0.4 Gy) significantly enhanced HR frequency, possibly through induction of DNA repair/recombination machinery including ataxia-telangiectasia mutated, histone H2A.X and RAD51 proteins. LDI could also increase HR efficiency by more than 30-fold when combined with the targeting tools zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats. Whole-exome sequencing confirmed that the LDI administered to hPSCs did not induce gross genomic alterations or affect cellular viability. Irradiated and targeted lines were karyotypically normal and made all differentiated lineages that continued to express green fluorescent protein targeted at the AAVS1 locus. This simple method allows higher throughput of new, targeted hPSC lines that are crucial to expand the use of disease modeling and to develop novel avenues of cell therapy. The simple and relevant technique described in this report uses a low level of radiation to increase desired gene modifications in human pluripotent stem cells by an order of magnitude. This higher efficiency permits greater throughput with reduced time and cost. The low level of radiation also greatly increased the recombination frequency when combined with developed engineered nucleases. Critically, the radiation did not lead to increases in DNA mutations or to reductions in overall cellular viability. This novel technique enables not only the rapid production of disease models using human stem cells but also the possibility of treating genetically based diseases by correcting patient-derived cells. ©AlphaMed Press.

  7. Intensity-Modulated Radiotherapy for Craniospinal Irradiation: Target Volume Considerations, Dose Constraints, and Competing Risks

    International Nuclear Information System (INIS)

    Parker, William; Filion, Edith; Roberge, David; Freeman, Carolyn R.

    2007-01-01

    Purpose: To report the results of an analysis of dose received to tissues and organs outside the target volume, in the setting of spinal axis irradiation for the treatment of medulloblastoma, using three treatment techniques. Methods and Materials: Treatment plans (total dose, 23.4 Gy) for a standard two-dimensional (2D) technique, a three-dimensional (3D) technique using a 3D imaging-based target volume, and an intensity-modulated radiotherapy (IMRT) technique, were compared for 3 patients in terms of dose-volume statistics for target coverage, as well as organ at risk (OAR) and overall tissue sparing. Results: Planning target volume coverage and dose homogeneity was superior for the IMRT plans for V 95% (IMRT, 100%; 3D, 96%; 2D, 98%) and V 107% (IMRT, 3%; 3D, 38%; 2D, 37%). In terms of OAR sparing, the IMRT plan was better for all organs and whole-body contour when comparing V 10Gy , V 15Gy , and V 20Gy . The 3D plan was superior for V 5Gy and below. For the heart and liver in particular, the IMRT plans provided considerable sparing in terms of V 10Gy and above. In terms of the integral dose, the IMRT plans were superior for liver (IMRT, 21.9 J; 3D, 28.6 J; 2D, 38.6 J) and heart (IMRT, 9 J; 3D, 14.1J; 2D, 19.4 J), the 3D plan for the body contour (IMRT, 349 J; 3D, 337 J; 2D, 555 J). Conclusions: Intensity-modulated radiotherapy is a valid treatment option for spinal axis irradiation. We have shown that IMRT results in sparing of organs at risk without a significant increase in integral dose

  8. Chlorin e6 Conjugated Interleukin-6 Receptor Aptamers Selectively Kill Target Cells Upon Irradiation

    Directory of Open Access Journals (Sweden)

    Sven Kruspe

    2014-01-01

    Full Text Available Photodynamic therapy (PDT uses the therapeutic properties of light in combination with certain chemicals, called photosensitizers, to successfully treat brain, breast, prostate, and skin cancers. To improve PDT, current research focuses on the development of photosensitizers to specifically target cancer cells. In the past few years, aptamers have been developed to directly deliver cargo molecules into target cells. We conjugated the photosensitizer chlorin e6 (ce6 with a human interleukin-6 receptor (IL-6R binding RNA aptamer, AIR-3A yielding AIR-3A-ce6 for application in high efficient PDT. AIR-3A-ce6 was rapidly and specifically internalized by IL-6R presenting (IL-6R+ cells. Upon light irradiation, targeted cells were selectively killed, while free ce6 did not show any toxic effect. Cells lacking the IL-6R were also not affected by AIR-3A-ce6. With this approach, we improved the target specificity of ce6-mediated PDT. In the future, other tumor-specific aptamers might be used to selectively localize photosensitizers into cells of interest and improve the efficacy and specificity of PDT in cancer and other diseases.

  9. Blast-Wave Generation and Propagation in Rapidly Heated Laser-Irradiated Targets

    Science.gov (United States)

    Ivancic, S. T.; Stillman, C. R.; Nilson, P. M.; Solodov, A. A.; Froula, D. H.

    2017-10-01

    Time-resolved extreme ultraviolet (XUV) spectroscopy was used to study the creation and propagation of a >100-Mbar blast wave in a target irradiated by an intense (>1018WWcm2 cm2) laser pulse. Blast waves provide a platform to generate immense pressures in the laboratory. A temporal double flash of XUV radiation was observed when viewing the rear side of the target, which is attributed to the emergence of a blast wave following rapid heating by a fast-electron beam generated from the laser pulse. The time-history of XUV emission in the photon energy range of 50 to 200 eV was recorded with an x-ray streak camera with 7-ps temporal resolution. The heating and expansion of the target was simulated with an electron transport code coupled to 1-D radiation-hydrodynamics simulations. The temporal delay between the two flashes measured in a systematic study of target thickness and composition was found to evolve in good agreement with a Sedov-Taylor blast-wave solution. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944 and Department of Energy Office of Science Award Number DE-SC-0012317.

  10. Effects on Implosion Characteristics of High-Z Dopant Profiles in ICF Ignition Capsule Ablators

    Science.gov (United States)

    Li, Yongsheng; Wang, Min; Gu, Jianfa; Zou, Shiyang; Kang, Dongguo; Ye, Wenhua; Zhang, Weiyan

    2012-10-01

    For ignition target design (ITD) of indirect drive ICF [J. Lindl, PoP 2, 3933(1995)], high-Z dopants in capsule ablators were used to prevent preheat of DTadjacentablators by Au M-band flux in laser-driven gold Hohlraums, therefore to restrain the growth of high-mode hydro-instabilities and to improve the targetrobustness.Based on NIC's Rev. 5 ITD[S. W. Haan et al., PoP 18, 051001(2011)], we investigated the effect of thickness and dopant concentration of doped layers on implosion characteristics, including the Atwood number (AWN) of fuel-ablator interface, the density gradient scale length (DGSL) of ablation front and the implosion velocity (VIM); all three variables decrease with increment of dopant dosage, and increase with dopant concentration while keeping dosage constant. Since a smaller AWN, a larger DGSL, and a faster VIM always characterize a more robust ITD, one should make tradeoff among them by adjusting the dopant profiles in ablators.A Gaussian spectrum (GS) was used to imitate the Au M-band flux [Y. S. Li et al., PoP 18, 022701(2011)], and the impact of GScenter on implosion characteristics of Rev. 5 ITD was studied while moving the GScenter towards higher energy, the ablatorpreheat got severe, AWN got larger, DGSL got larger, and VIM got faster.

  11. Detection and Imaging of High-Z Materials with a Muon Tomography Station Using GEM Detectors

    CERN Document Server

    Gnanvo, K; Bittner, W; Costa, F; Grasso, L; Hohlmann, M; Locke, J B; Martoiu, S; Muller, H; Staib, M; Tarazona, A; Toledo, J

    2010-01-01

    Muon tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons is a promising technique for detecting and imaging heavily shielded high-Z nuclear materials such as enriched uranium. This technique could complement standard radiation detection portals currently deployed at international borders and ports, which are not very sensitive to heavily shielded nuclear materials. We image small targets in 3D using $2\\times 2 \\times 2$ mm^3 voxels with a minimal muon tomography station prototype that tracks muons with Gas Electron Multiplier (GEM) detectors read out in 2D with x-y microstrips of 400 micron pitch. With preliminary electronics, the GEM detectors achieve a spatial resolution of 130 microns in both dimensions. With the next GEM-based prototype station we plan to probe an active volume of ~27 liters. We present first results on reading out all 1536 microstrips of a $30 \\times 30$ cm^2 GEM detector for the next muon tomography prototype with final frontend electronics and DAQ...

  12. Development of a PVD-based manufacturing process of monolithic LEU irradiation targets for {sup 99}Mo production

    Energy Technology Data Exchange (ETDEWEB)

    Hollmer, Tobias

    2015-08-03

    {sup 99}Mo is the most important radioisotope in nuclear medicine. It is produced by fission of uranium in irradiation targets. The usage of cylindrical monolithic targets can ensure a safe supply of {sup 99}Mo and at the same reduce the amount of highly radioactive waste generated during production. To manufacture these targets, a novel PVD-based technique was developed. Both the feasibility and the high efficiency of this process were demonstrated in a prototype apparatus.

  13. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    Energy Technology Data Exchange (ETDEWEB)

    Rapp, Juergen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Aaron, A. M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bell, Gary L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burgess, Thomas W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ellis, Ronald James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Giuliano, D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kiggans, James O. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lessard, Timothy L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ohriner, Evan Keith [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Perkins, Dale E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Varma, Venugopal Koikal [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-10-20

    Fusion energy is the most promising energy source for the future, and one of the most important problems to be solved progressing to a commercial fusion reactor is the identification of plasma-facing materials compatible with the extreme conditions in the fusion reactor environment. The development of plasma–material interaction (PMI) science and the technology of plasma-facing components are key elements in the development of the next step fusion device in the United States, the so-called Fusion Nuclear Science Facility (FNSF). All of these PMI issues and the uncertain impact of the 14-MeV neutron irradiation have been identified in numerous expert panel reports to the fusion community. The 2007 Greenwald report classifies reactor plasma-facing materials (PFCs) and materials as the only Tier 1 issues, requiring a “. . . major extrapolation from the current state of knowledge, need for qualitative improvements and substantial development for both the short and long term.” The Greenwald report goes on to list 19 gaps in understanding and performance related to the plasma–material interface for the technology facilities needed for DEMO-oriented R&D and DEMO itself. Of the 15 major gaps, six (G7, G9, G10, G12, G13) can possibly be addressed with ORNL’s proposal of an advanced Material Plasma Exposure eXperiment. Establishing this mid-scale plasma materials test facility at ORNL is a key element in ORNL’s strategy to secure a leadership role for decades of fusion R&D. That is to say, our end goal is to bring the “signature facility” FNSF home to ORNL. This project is related to the pre-conceptual design of an innovative target station for a future Material–Plasma Exposure eXperiment (MPEX). The target station will be designed to expose candidate fusion reactor plasma-facing materials and components (PFMs and PFCs) to conditions anticipated in fusion reactors, where PFCs will be exposed to dense high-temperature hydrogen plasmas providing steady

  14. Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

    International Nuclear Information System (INIS)

    Rapp, Juergen; Aaron, A. M.; Bell, Gary L.; Burgess, Thomas W.; Ellis, Ronald James; Giuliano, D.; Howard, R.; Kiggans, James O.; Lessard, Timothy L.; Ohriner, Evan Keith; Perkins, Dale E.; Varma, Venugopal Koikal

    2015-01-01

    Fusion energy is the most promising energy source for the future, and one of the most important problems to be solved progressing to a commercial fusion reactor is the identification of plasma-facing materials compatible with the extreme conditions in the fusion reactor environment. The development of plasma-material interaction (PMI) science and the technology of plasma-facing components are key elements in the development of the next step fusion device in the United States, the so-called Fusion Nuclear Science Facility (FNSF). All of these PMI issues and the uncertain impact of the 14-MeV neutron irradiation have been identified in numerous expert panel reports to the fusion community. The 2007 Greenwald report classifies reactor plasma-facing materials (PFCs) and materials as the only Tier 1 issues, requiring a ''. . . major extrapolation from the current state of knowledge, need for qualitative improvements and substantial development for both the short and long term.'' The Greenwald report goes on to list 19 gaps in understanding and performance related to the plasma-material interface for the technology facilities needed for DEMO-oriented R&D and DEMO itself. Of the 15 major gaps, six (G7, G9, G10, G12, G13) can possibly be addressed with ORNL's proposal of an advanced Material Plasma Exposure eXperiment. Establishing this mid-scale plasma materials test facility at ORNL is a key element in ORNL's strategy to secure a leadership role for decades of fusion R&D. That is to say, our end goal is to bring the ''signature facility'' FNSF home to ORNL. This project is related to the pre-conceptual design of an innovative target station for a future Material-Plasma Exposure eXperiment (MPEX). The target station will be designed to expose candidate fusion reactor plasma-facing materials and components (PFMs and PFCs) to conditions anticipated in fusion reactors, where PFCs will be exposed to dense high-temperature hydrogen plasmas providing steady-state heat fluxes of

  15. Irradiation cryostat for LiH and LiD polarized solid targets

    International Nuclear Information System (INIS)

    Goertz, S.

    1991-01-01

    Scattering experiments with polarized nucleon targets are an important tool to understand the nuclear spin structure. Pion photoproduction experiments on polarized protrons and neutrons as well as measurements of the neutron and deuteron formfactors will be performed at ELSA. 7 LiH and 6 LiD seem to be attractive target materials for these experiments, because they offer high proton and deuteron polarisation, respectively. Expecially 6 LiD has further very important advantages compared to the common deuteron target materials as d-Butanol and ND 3 . This work describes the mechanism of DNP (Dynamic Nuclear Polarization) in LiH and LiD and gives a view on the nature of the so-called paramagnetic impurities in these materials. In order to maximize the nuclear polarization, the production of these radicals have to take place under well defined temperature conditions. Therefore the first version of an irradiation cryostat was built and tested in regard to its cooling power and temperature adjustment. (orig.)

  16. Shielding Aspects of Accelerators, Targets and Irradiation Facilities - SATIF-11 Workshop Proceedings Report

    International Nuclear Information System (INIS)

    2013-01-01

    Particle accelerators have evolved over the last decades from simple devices to powerful machines. In recent years, new technological and research applications have helped to define requirements while the number of accelerator facilities in operation, being commissioned, designed or planned has grown significantly. Their parameters, which include the beam energy, currents and intensities, and target composition, can vary widely, giving rise to new radiation shielding issues and challenges. Particle accelerators must be operated in safe ways to protect operators, the public and the environment. As the design and use of these facilities evolve, so must the analytical methods used in the safety analyses. These workshop proceedings review the state of the art in radiation shielding of accelerator facilities and irradiation targets. They also evaluate progress in the development of modelling methods used to assess the effectiveness of such shielding as part of safety analyses. The transport of radiation through shielding materials is a major consideration in the safety design studies of nuclear power plants, and the modelling techniques used may be applied to many other types of scientific and technological facilities. Accelerator and irradiation facilities represent a key capability in R and D, medical and industrial infrastructures, and they can be used in a wide range of scientific, medical and industrial applications. High-energy ion accelerators, for example, are now used not only in fundamental research, such as the search for new super-heavy nuclei, but also for therapy as part of cancer treatment. While the energy of the incident particles on the shielding of these facilities may be much higher than those found in nuclear power plants, much of the physics associated with the behaviour of the secondary particles produced is similar, as are the computer modelling techniques used to quantify key safety design parameters, such as radiation dose and activation levels

  17. Measurements of the divergence of fast electrons in laser-irradiated spherical targets

    International Nuclear Information System (INIS)

    Yaakobi, B.; Solodov, A. A.; Myatt, J. F.; Delettrez, J. A.; Stoeckl, C.; Froula, D. H.

    2013-01-01

    In recent experiments using directly driven spherical targets on the OMEGA laser system, the energy in fast electrons was found to reach ∼1% of the laser energy at an irradiance of ∼1.1 × 10 15 W/cm 2 . The fraction of these fast electrons absorbed in the compressed fuel shell depends on their angular divergence. This paper describes measurements of this divergence deduced from a series of shots where Mo-coated shells of increasing diameter (D) were suspended within an outer CH shell. The intensity of the Mo–Kα line and the hard x-ray radiation were found to increase approximately as ∼D 2 , indicating wide divergence of the fast electrons. Alternative interpretations of these results (electron scattering, radiation excitation of Kα, and an electric field due to return current) are shown to be unimportant

  18. Solid targets and irradiation facilities for production of diagnostic and therapeutic radionuclides at the Debrecen cyclotron

    International Nuclear Information System (INIS)

    Tarkanyi, F.; Ando, L.; Szucs, Z.; Mahunka, I.; Kovacs, Z.

    2000-01-01

    The MGC-20E (NIIEFA, Leningrad, USSR) variable energy compact cyclotron (k=20) was installed in ATOMKI (Debrecen, Hungary) in 1985. Protons, deuterons, 3 He- and α-particles can be accelerated with currents up to 300 μA for internal irradiation and up to 50 μA for external beams. The establishment of the Cyclotron Laboratory was partly supported by the International Atomic Energy Agency. The application of the cyclotron is multipurpose: basic nuclear research, application of activation technique for analytical and wear studies, application of intense fast neutron source for agro-biological, bio-medical application and for radiation damage test of electronic components, and finally radioisotope production for medical diagnostics and for other scientific and applied fields. The cyclotron laboratory has six target rooms, a radiochemistry laboratory and a medical unit equipped with PET

  19. Role of choline PET/CT in guiding target volume delineation for irradiation of prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Schwarzenboeck, S.M.; Kurth, J. [University Medical Centre Rostock, Department of Nuclear Medicine, Rostock (Germany); Gocke, C.; Kuhnt, T.; Hildebrandt, G. [University Medical Centre Rostock, Department of Radiotherapy, Rostock (Germany); Krause, B.J. [University Medical Centre Rostock, Department of Nuclear Medicine, Rostock (Germany); Universitaet Rostock, Department of Nuclear Medicine, Universitaetsmedizin Rostock, Rostock (Germany)

    2013-07-15

    Choline PET/CT has shown limitations for the detection of primary prostate cancer and nodal metastatic disease, mainly due to limited sensitivity and specificity. Conversely in the restaging of prostate cancer recurrence, choline PET/CT is a promising imaging modality for the detection of local regional and nodal recurrence with an impact on therapy management. This review highlights current literature on choline PET/CT for radiation treatment planning in primary and recurrent prostate cancer. Due to limited sensitivity and specificity in differentiating between benign and malignant prostatic tissues in primary prostate cancer, there is little enthusiasm for target volume delineation based on choline PET/CT. Irradiation planning for the treatment of single lymph node metastases on the basis of choline PET/CT is controversial due to its limited lesion-based sensitivity in primary nodal staging. In high-risk prostate cancer, choline PET/CT might diagnose lymph node metastases, which potentially can be included in the conventional irradiation field. Prior to radiation treatment of recurrent prostate cancer, choline PET/CT may prove useful for patient stratification by excluding distant disease which would require systemic therapy. In patients with local recurrence, choline PET/CT can be used to delineate local sites of recurrence within the prostatic resection bed allowing a boost to PET-positive sites. In patients with lymph node metastases outside the prostatic fossa and regional metastatic lymph nodes, choline PET/CT might influence radiation treatment planning by enabling extension of the target volume to lymphatic drainage sites with or without a boost to PET-positive lymph nodes. Further clinical randomized trials are required to assess treatment outcomes following choline-based biological radiation treatment planning in comparison with conventional radiation treatment planning. (orig.)

  20. Estrogen enhanced cell-cell signalling in breast cancer cells exposed to targeted irradiation

    International Nuclear Information System (INIS)

    Shao, Chunlin; Folkard, Melvyn; Held, Kathryn D; Prise, Kevin M

    2008-01-01

    Radiation-induced bystander responses, where cells respond to their neighbours being irradiated are being extensively studied. Although evidence shows that bystander responses can be induced in many types of cells, it is not known whether there is a radiation-induced bystander effect in breast cancer cells, where the radiosensitivity may be dependent on the role of the cellular estrogen receptor (ER). This study investigated radiation-induced bystander responses in estrogen receptor-positive MCF-7 and estrogen receptor-negative MDA-MB-231 breast cancer cells. The influence of estrogen and anti-estrogen treatments on the bystander response was determined by individually irradiating a fraction of cells within the population with a precise number of helium-3 using a charged particle microbeam. Damage was scored as chromosomal damage measured as micronucleus formation. A bystander response measured as increased yield of micronucleated cells was triggered in both MCF-7 and MDA-MB-231 cells. The contribution of the bystander response to total cell damage in MCF-7 cells was higher than that in MDA-MB-231 cells although the radiosensitivity of MDA-MB-231 was higher than MCF-7. Treatment of cells with 17β-estradiol (E2) increased the radiosensitivity and the bystander response in MCF-7 cells, and the effect was diminished by anti-estrogen tamoxifen (TAM). E2 also increased the level of intracellular reactive oxygen species (ROS) in MCF-7 cells in the absence of radiation. In contrast, E2 and TAM had no influence on the bystander response and ROS levels in MDA-MB-231 cells. Moreover, the treatment of MCF-7 cells with antioxidants eliminated both the E2-induced ROS increase and E2-enhanced bystander response triggered by the microbeam irradiation, which indicates that ROS are involved in the E2-enhanced bystander micronuclei formation after microbeam irradiation. The observation of bystander responses in breast tumour cells may offer new potential targets for radiation

  1. Effects of Thin High-z Layers on the Hydrodynamics of Laser-Accelerated Plastic Targets

    National Research Council Canada - National Science Library

    Obenschain, S. P; Colombant, D; Karasik, M; Pawley, C. J; Serlin, V; Schmitt, A. J; Gardner, J. H; Phillips, L; Aglitskly, Y; Chan, Y

    2002-01-01

    .... This pulse shape simulates the generic shape needed for high-gain fusion implosions. Imprint of laser nonuniformity during start up of the low intensity foot is a well-known seed for hydrodynamic instability...

  2. Targeting carbonic anhydrase IX by nitroimidazole based sulfamides enhances the therapeutic effect of tumor irradiation: A new concept of dual targeting drugs

    International Nuclear Information System (INIS)

    Dubois, Ludwig; Peeters, Sarah G.J.A.; Kuijk, Simon J.A. van; Yaromina, Ala; Lieuwes, Natasja G.; Saraya, Ruchi; Biemans, Rianne; Rami, Marouan; Parvathaneni, Nanda Kumar; Vullo, Daniela; Vooijs, Marc; Supuran, Claudiu T.; Winum, Jean-Yves

    2013-01-01

    Background and purpose: Carbonic anhydrase IX (CAIX) plays an important role in pH regulation processes critical for tumor cell growth and metastasis. We hypothesize that a dual targeting bioreductive nitroimidazole based anti-CAIX sulfamide drug (DH348) will reduce tumor growth and sensitize tumors to irradiation in a CAIX dependent manner. Material and methods: The effect of the dual targeting anti-CAIX (DH348) and its single targeting control drugs on extracellular acidification and radiosensitivity was examined in HT-29 colorectal carcinoma cells. Tumor growth and time to reach 4× start volume (T4×SV) was monitored for animals receiving DH348 (10 mg/kg) combined with tumor single dose irradiation (10 Gy). Results: In vitro, DH348 reduced hypoxia-induced extracellular acidosis, but did not change hypoxic radiosensitivity. In vivo, DH348 monotherapy decreased tumor growth rate and sensitized tumors to radiation (enhancement ratio 1.50) without systemic toxicity only for CAIX expressing tumors. Conclusions: A newly designed nitroimidazole and sulfamide dual targeting drug reduces hypoxic extracellular acidification, slows down tumor growth at nontoxic doses and sensitizes tumors to irradiation all in a CAIX dependent manner, suggesting no “off-target” effects. Our data therefore indicate the potential utility of a dual drug approach as a new strategy for tumor-specific targeting

  3. Positron annihilation lifetime measurements of austenitic stainless and ferritic/martensitic steels irradiated in the SINQ target irradiation program

    Science.gov (United States)

    Sato, K.; Xu, Q.; Yoshiie, T.; Dai, Y.; Kikuchi, K.

    2012-12-01

    Titanium-doped austenitic stainless steel (JPCA) and reduced activated ferritic/martensitic steel (F82H) irradiated with high-energy protons and spallation neutrons were investigated by positron annihilation lifetime measurements. Subnanometer-sized (steel, the positron annihilation lifetime of the bubbles decreased with increasing irradiation dose and annealing temperature because the bubbles absorb additional He atoms. In the case of JPCA steel, the positron annihilation lifetime increased with increasing annealing temperature above 773 K, in which case the dissociation of complexes of vacancy clusters with He atoms and the growth of He bubbles was detected. He bubble size and density were also discussed.

  4. High-Z material erosion and its control in DIII-D carbon divertor

    Directory of Open Access Journals (Sweden)

    R. Ding

    2017-08-01

    Full Text Available As High-Z materials will likely be used as plasma-facing components (PFCs in future fusion devices, the erosion of high-Z materials is a key issue for high-power, long pulse operation. High-Z material erosion and redeposition have been studied using tungsten and molybdenum coated samples exposed in well-diagnosed DIII-D divertor plasma discharges. By coupling dedicated experiments and modelling using the 3D Monte Carlo code ERO, the roles of sheath potential and background carbon impurities in determining high-Z material erosion are identified. Different methods suggested by modelling have been investigated to control high-Z material erosion in DIII-D experiments. The erosion of Mo and W is found to be strongly suppressed by local injection of methane and deuterium gases. The 13C deposition resulting from local 13CH4 injection also provides information on radial transport due to E ×B drifts and cross field diffusion. Finally, D2 gas puffing is found to cause local plasma perturbation, suppressing W erosion because of the lower effective sputtering yield of W at lower plasma temperature and for higher carbon concentration in the mixed surface layer.

  5. Measurements of the Properties of Highly-charged high-Z ions

    International Nuclear Information System (INIS)

    Augustine J. Smith, Ph.D.

    2007-01-01

    We had proposed carrying out a systematic experimental investigation of the atomic physics of highly charged, high-Z ions, produced in the Lawrence Livermore National Laboratory LLNL electron beam ion trap (EBIT-I) in its high energy mode, superEBIT. In particular we were going to accurately measure line positions for Δn=0 transitions in few electron high-Z ions; this was meant to enable us to investigate relativistic and quantum electrodynamics QED contributions to the energy levels as well as the nuclear properties of heavy ions. We were also going to measure cross sections for various electron-ion interactions, the degree of polarization of emitted x-rays, and radiation cooling rates of various ionization stages of highly charged, high-Z ions. This would enable us to study fundamental atomic physics of high-Z ions at relativistic electron impact energies and in the intense nuclear fields of highly ionized, high-Z ions. This would extend previous measurements we have carried out to a regime where there is a paucity of good data. These measurements were expected to generate increased theoretical interest and activity in this area. The project will extend a very successful collaboration between Morehouse College (MC) and a national laboratory LLNL, Minority student training and development are major components of the proposal

  6. Fiscal year 1976 DT fusion neutron irradiations and dosimetry at the LLL rotating target neutron source

    International Nuclear Information System (INIS)

    MacLean, S.C.

    1977-01-01

    The DT fusion neutron irradiation of 319 samples during 19 irradiation periods (beam-on time of more than 1026 hours) is described. Experiments from 24 individuals representing 11 institutions are summarized. The numbers of the UCID dosimetry reports detailing each of the irradiations are given

  7. Influence of lateral target size on hot electron production and electromagnetic pulse emission from laser-irradiated metallic targets

    International Nuclear Information System (INIS)

    Chen Ziyu; Li Jianfeng; Yu Yong; Li Xiaoya; Peng Qixian; Zhu Wenjun; Wang Jiaxiang

    2012-01-01

    The influences of lateral target size on hot electron production and electromagnetic pulse emission from laser interaction with metallic targets have been investigated. Particle-in-cell simulations at high laser intensities show that the yield of hot electrons tends to increase with lateral target size, because the larger surface area reduces the electrostatic field on the target, owing to its expansion along the target surface. At lower laser intensities and longer time scales, experimental data characterizing electromagnetic pulse emission as a function of lateral target size also show target-size effects. Charge separation and a larger target tending to have a lower target potential have both been observed. The increase in radiation strength and downshift in radiation frequency with increasing lateral target size can be interpreted using a simple model of the electrical capacity of the target.

  8. Influence of lateral target size on hot electron production and electromagnetic pulse emission from laser-irradiated metallic targets

    Energy Technology Data Exchange (ETDEWEB)

    Chen Ziyu; Li Jianfeng; Yu Yong; Li Xiaoya; Peng Qixian; Zhu Wenjun [National Key Laboratory of Shock Wave and Detonation Physics, Institute of Fluid Physics, China Academy of Engineering Physics, Mianyang, Sichuan 621900 (China); Wang Jiaxiang [State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062 (China)

    2012-11-15

    The influences of lateral target size on hot electron production and electromagnetic pulse emission from laser interaction with metallic targets have been investigated. Particle-in-cell simulations at high laser intensities show that the yield of hot electrons tends to increase with lateral target size, because the larger surface area reduces the electrostatic field on the target, owing to its expansion along the target surface. At lower laser intensities and longer time scales, experimental data characterizing electromagnetic pulse emission as a function of lateral target size also show target-size effects. Charge separation and a larger target tending to have a lower target potential have both been observed. The increase in radiation strength and downshift in radiation frequency with increasing lateral target size can be interpreted using a simple model of the electrical capacity of the target.

  9. Analytical solutions for thermal transient profile in solid target irradiated with low energy and high beam current protons

    International Nuclear Information System (INIS)

    Oliveira, Henrique B. de; Brazao, Nei G.; Sciani, Valdir

    2009-01-01

    There were obtained analytical solutions for thermal transient in solid targets, used in short half-life radioisotopes production, when irradiated with low energy and high beam current protons, in the cyclotron accelerator Cyclone 30 of the Institute for Energy and Nuclear Research (IPEN/CNEN-SP). The beam spatial profile was considered constant and the time depended heat distribution equation was resolved for a continuous particles flow entering the target. The problem was divided into two stages: a general solution was proposed which is the sum of two functions, the first one related to the thermal equilibrium situation and the second one related to a time dependent function that was determinate by the setting of the contour conditions and the initial conditions imposed by the real problem. By that one got an analytic function for a complete description of the heat transport phenomenon inside the targets. There were used both, numerical and symbolic computation methods, to obtain temperature maps and thermal gradients and the results showed an excellent agreement when compared with purely numerical models. The results were compared with obtained data from Gallium-67 and Thallium-201 irradiation routines conducted by the IPEN Cyclotrons accelerators center, showing excellent agreement. The objective of this paper is to develop solid targets irradiation systems (metals and oxides) so that one can operate with high levels of current beam, minimizing the irradiation time and maximizing the final returns. (author)

  10. Solvent extraction of no-carrier-added 103Pd from irradiated rhodium target with α-furyldioxime

    International Nuclear Information System (INIS)

    Mahdi Sadeghi; Behrouz Shirazi; Nami Shadanpour

    2006-01-01

    Solvent extraction of no-carrier-added 103 Pd was investigated from irradiated rhodium target with a-furyldioxime in chloroform from diluted hydrochloric acid. Extraction yield was 85.3% for a single extraction from 0.37M HCl and 103 Pd purity was better than 99%. (author)

  11. Cross sections for the production of Li and Be isotopes in carbon targets irradiated by 300 GeV protons

    International Nuclear Information System (INIS)

    Raisbeck, G.M.; Lestringuez, J.; Yiou, F.

    1975-01-01

    Cross sections for the production of Li and Be isotopes in carbon targets irradiated by 300 GeV protons were measured by mass spectrometry. The results are compared with lower energy measurements and discussed in terms of the variation of the cosmic ray L/M ratio in this energy region [fr

  12. Cross sections for the production of Li and Be isotopes in carbon targets irradiated by 300 GeV protons

    International Nuclear Information System (INIS)

    Raisbeck, G.M.; Lestringuez, J.; Yiou, F.

    1975-01-01

    Cross sections for the production of Li and Be isotopes in carbon targets irradiated by 300 GeV protons have been measured by mass spectrometry. The results are compared with lower energy measurements and discussed in terms of the variation of the cosmic ray L/M ratio in the energy region [fr

  13. Targeting pro-apoptotic trail receptors sensitizes HeLa cervical cancer cells to irradiation-induced apoptosis

    NARCIS (Netherlands)

    Maduro, John H.; de Vries, Elisabeth G. E.; Meersma, Gert-Jan; Hougardy, Brigitte M. T.; van der Zee, Ate G. J.; De Jong, Steven

    2008-01-01

    Purpose: To investigate the potential of irradiation in combination with drugs targeting the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptor (DR)4 and DR5 and their mechanism of action in a cervical cancer cell line. Methods and Materials: Recombinant human TRAIL

  14. Formation of excited states in high-Z helium-like systems

    International Nuclear Information System (INIS)

    Fritzsche, S.; Fricke, B.; Brinzanescu, O.

    1999-12-01

    High-Z helium-like ions represent the simplest multi-electron systems for studying the interplay between electron-electron correlations, relativistic as well as quantum electrodynamical effects in strong fields. In contrast to the adjacent lithium-like ions, however, almost no experimental information is available about the excited states in the high-Z domain of the helium sequence. Here, we present a theoretical analysis of the X-ray production and decay dynamics of the excited states in helium-like uranium. Emphasize has been paid particularly to the formation of the 3 P 0 and 3 P 2 levels by using electron capture into hydrogen-like U 91+ . Both states are of interest for precise measurements on high-Z helium-like ions in the future. (orig.)

  15. Positron annihilation lifetime measurements of austenitic stainless and ferritic/martensitic steels irradiated in the SINQ target irradiation program

    Energy Technology Data Exchange (ETDEWEB)

    Sato, K., E-mail: ksato@rri.kyoto-u.ac.jp [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Xu, Q.; Yoshiie, T. [Research Reactor Institute, Kyoto University, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan); Dai, Y. [Spallation Neutron Source Division, Paul Scherrer Institute, CH-5232 Villigen PSI (Switzerland); Kikuchi, K. [Frontier Research Center for Applied Atomic Sciences, Ibaraki University, Tokai-mura, Naka-gun, Ibaraki 319-1106 (Japan)

    2012-12-15

    Titanium-doped austenitic stainless steel (JPCA) and reduced activated ferritic/martensitic steel (F82H) irradiated with high-energy protons and spallation neutrons were investigated by positron annihilation lifetime measurements. Subnanometer-sized (<{approx}0.8 nm) helium bubbles, which cannot be observed by transmission electron microscopy, were detected by positron annihilation lifetime measurements for the first time. For the F82H steel, the positron annihilation lifetime of the bubbles decreased with increasing irradiation dose and annealing temperature because the bubbles absorb additional He atoms. In the case of JPCA steel, the positron annihilation lifetime increased with increasing annealing temperature above 773 K, in which case the dissociation of complexes of vacancy clusters with He atoms and the growth of He bubbles was detected. He bubble size and density were also discussed.

  16. Positron annihilation lifetime measurements of austenitic stainless and ferritic/martensitic steels irradiated in the SINQ target irradiation program

    International Nuclear Information System (INIS)

    Sato, K.; Xu, Q.; Yoshiie, T.; Dai, Y.; Kikuchi, K.

    2012-01-01

    Titanium-doped austenitic stainless steel (JPCA) and reduced activated ferritic/martensitic steel (F82H) irradiated with high-energy protons and spallation neutrons were investigated by positron annihilation lifetime measurements. Subnanometer-sized (<∼0.8 nm) helium bubbles, which cannot be observed by transmission electron microscopy, were detected by positron annihilation lifetime measurements for the first time. For the F82H steel, the positron annihilation lifetime of the bubbles decreased with increasing irradiation dose and annealing temperature because the bubbles absorb additional He atoms. In the case of JPCA steel, the positron annihilation lifetime increased with increasing annealing temperature above 773 K, in which case the dissociation of complexes of vacancy clusters with He atoms and the growth of He bubbles was detected. He bubble size and density were also discussed.

  17. SU-D-304-02: Magnetically Focused Proton Irradiation of Small Field Targets

    International Nuclear Information System (INIS)

    McAuley, GA; Slater, JM; Slater, JD; Wroe, AJ

    2015-01-01

    Purpose: To investigate the use of magnetic focusing for small field proton irradiations. It is hypothesized that magnetic focusing will provide significant dose distribution benefits over standard collimated beams for fields less than 10 mm diameter. Methods: Magnets consisting of 24 segments of radiation hard samarium-cobalt adhered into hollow cylinders were designed and manufactured. Two focusing magnets were placed on a positioning track on our Gantry 1 treatment table. Proton beams with energies of 127 and 157 MeV, 15 and 30 mm modulation, and 8 mm initial diameters were delivered to a water tank using single-stage scattering. Depth dose distributions were measured using a PTW PR60020 diode detector and transverse profiles were measured with Gafchromic EBT3 film. Monte Carlo simulations were also performed - both for comparison with experimental data and to further explore the potential of magnetic focusing in silica. For example, beam spot areas (based on the 90% dose contour) were matched at Bragg depth between simulated 100 MeV collimated beams and simulated beams focused by two 400 T/m gradient magnets. Results: Preliminary experimental results show 23% higher peak to entrance dose ratios and flatter spread out Bragg peak plateaus for 8 mm focused beams compared with uncollimated beams. Monte Carlo simulations showed 21% larger peak to entrance ratios and a ∼9 fold more efficient dose to target delivery compared to spot-sized matched collimated beams. Our latest results will be presented. Conclusion: Our results suggest that rare earth focusing magnet assemblies could reduce skin dose and beam number while delivering dose to nominally spherical radiosurgery targets over a much shorter time compared to unfocused beams. Immediate clinical applications include those associated with proton radiosurgery and functional radiosurgery of the brain and spine, however expanded treatment sites can be also envisaged

  18. WE-D-17A-04: Magnetically Focused Proton Irradiation of Small Volume Targets

    Energy Technology Data Exchange (ETDEWEB)

    McAuley, G; Slater, J [Loma Linda University, Loma Linda, CA (United States); Wroe, A [Loma Linda University Medical Center, Loma Linda, CA (United States)

    2014-06-15

    Purpose: To explore the advantages of magnetic focusing for small volume proton irradiations and the potential clinical benefits for radiosurgery targets. The primary goal is to create narrow elongated proton beams of elliptical cross section with superior dose delivery characteristics compared to current delivery modalities (eg, collimated beams). In addition, more general beam shapes are also under investigation. Methods: Two prototype magnets consisting of 24 segments of samarium-cobalt (Sm2Co17) permanent magnetic material adhered into hollow cylinders were manufactured for testing. A single focusing magnet was placed on a positioning track on our Gantry 1 treatment table and 15 mm diameter proton beams with energies and modulation relevant to clinical radiosurgery applications (127 to 186 MeV, and 0 to 30 mm modulation) were delivered to a terminal water tank. Beam dose distributions were measured using a PTW diode detector and Gafchromic EBT2 film. Longitudinal and transverse dose profiles were analyzed and compared to data from Monte Carlo simulations analogous to the experimental setup. Results: The narrow elongated focused beam spots showed high elliptical symmetry indicating high magnet quality. In addition, when compared to unfocused beams, peak-to-entrance depth dose ratios were 11 to 14% larger (depending on presence or extent of modulation), and minor axis penumbras were 11 to 20% smaller (again depending on modulation) for focused beams. These results suggest that the use of rare earth magnet assemblies is practical and could improve dose-sparing of normal tissue and organs at risk while delivering enhanced dose to small proton radiosurgery targets. Conclusion: Quadrapole rare earth magnetic assemblies are a promising and inexpensive method to counteract particle out scatter that tends to degrade the peak to entrance performance of small field proton beams. Knowledge gained from current experiments will inform the design of a prototype treatment

  19. SU-D-304-02: Magnetically Focused Proton Irradiation of Small Field Targets

    Energy Technology Data Exchange (ETDEWEB)

    McAuley, GA; Slater, JM [Loma Linda University, Loma Linda, CA (United States); Slater, JD; Wroe, AJ [Loma Linda University Medical Center, Loma Linda, CA (United States)

    2015-06-15

    Purpose: To investigate the use of magnetic focusing for small field proton irradiations. It is hypothesized that magnetic focusing will provide significant dose distribution benefits over standard collimated beams for fields less than 10 mm diameter. Methods: Magnets consisting of 24 segments of radiation hard samarium-cobalt adhered into hollow cylinders were designed and manufactured. Two focusing magnets were placed on a positioning track on our Gantry 1 treatment table. Proton beams with energies of 127 and 157 MeV, 15 and 30 mm modulation, and 8 mm initial diameters were delivered to a water tank using single-stage scattering. Depth dose distributions were measured using a PTW PR60020 diode detector and transverse profiles were measured with Gafchromic EBT3 film. Monte Carlo simulations were also performed - both for comparison with experimental data and to further explore the potential of magnetic focusing in silica. For example, beam spot areas (based on the 90% dose contour) were matched at Bragg depth between simulated 100 MeV collimated beams and simulated beams focused by two 400 T/m gradient magnets. Results: Preliminary experimental results show 23% higher peak to entrance dose ratios and flatter spread out Bragg peak plateaus for 8 mm focused beams compared with uncollimated beams. Monte Carlo simulations showed 21% larger peak to entrance ratios and a ∼9 fold more efficient dose to target delivery compared to spot-sized matched collimated beams. Our latest results will be presented. Conclusion: Our results suggest that rare earth focusing magnet assemblies could reduce skin dose and beam number while delivering dose to nominally spherical radiosurgery targets over a much shorter time compared to unfocused beams. Immediate clinical applications include those associated with proton radiosurgery and functional radiosurgery of the brain and spine, however expanded treatment sites can be also envisaged.

  20. A three-dimensional CT-based target definition for elective irradiation of the neck

    International Nuclear Information System (INIS)

    Nowak, Peter J.C.M.; Wijers, Oda B.; Lagerwaard, Frank J.; Levendag, Peter C.

    1999-01-01

    Introduction: Elective treatment of the clinically node-negative neck by radiation results in excellent control rates. However, radiation therapy with its organ-preserving properties is not without morbidity. Side effects of elective neck irradiation are mainly due to damage of the major and minor salivary glands, resulting in the dry mouth syndrome. Given that RT is the preferred treatment modality in case of elective treatment of the neck in many institutions, it is of utmost importance to try and reduce the associated sequelae of RT. Material and Methods: With the introduction of CT-planning systems and the development of 3D conformal radiation therapy (3D CRT) techniques, it has become feasible to deliver adequate doses of radiation to the target (neck) and at the same time saving (parts of) the salivary glands from doses beyond tolerance. A prerequisite for these techniques is that they require a precise knowledge of the target (i.e., of the elective neck) on CT. To be able to correlate borders of the surgical levels in the neck (I-VI) with structures seen on CT, an anatomical study, using two fixed (phenol, formaldehyde) human cadavers, was performed. Subsequently, the 6 potential lymph node regions in the neck on CT were defined. Results and Discussion: The reference for the current 3D CT-based definition of the lymph node regions in the neck is the official report of the American Academy of Otolaryngology, describing, based on surgical anatomy, the lymph node groups in the neck by Levels I-VI. The present investigation depicts reproducible landmarks on transversal CT images, corresponding to anatomical reference structures known from surgical levels (I-VI) and, this way, CT-based lymph node regions (1-6) were constructed

  1. Intrafractional Target Motions and Uncertainties of Treatment Setup Reference Systems in Accelerated Partial Breast Irradiation

    International Nuclear Information System (INIS)

    Yue, Ning J.; Goyal, Sharad; Zhou Jinghao; Khan, Atif J.; Haffty, Bruce G.

    2011-01-01

    Purpose: This study investigated the magnitude of intrafractional motion and level of accuracy of various setup strategies in accelerated partial breast irradiation (APBI) using three-dimensional conformal external beam radiotherapy. Methods and Materials: At lumpectomy, gold fiducial markers were strategically sutured to the surrounding walls of the cavity. Weekly fluoroscopy imaging was conducted at treatment to investigate the respiration-induced target motions. Daily pre- and post-RT kV imaging was performed, and images were matched to digitally reconstructed radiographs based on bony anatomy and fiducial markers, respectively, to determine the intrafractional motion magnitudes over the course of treatment. The positioning differences of the laser tattoo- and the bony anatomy-based setups compared with those of the marker-based setup (benchmark) were also determined. The study included 21 patients. Results: Although lung exhibited significant motion, the average marker motion amplitude on the fluoroscopic image was about 1 mm. Over a typical treatment time period, average intrafractional motion magnitude was 4.2 mm and 2.6 mm based on the marker and bony anatomy matching, respectively. The bony anatomy- and laser tattoo-based interfractional setup errors, with respect to the fiducial marker-based setup, were 7.1 and 9.0 mm, respectively. Conclusions: Respiration has limited effects on the target motion during APBI. Bony anatomy-based treatment setup improves the accuracy relative to that of the laser tattoo-based setup approach. Since fiducial markers are sutured directly to the surgical cavity, the marker-based approach can further improve the interfractional setup accuracy. On average, a seroma cavity exhibits intrafractional motion of more than 4 mm, a magnitude that is larger than that which is otherwise derived based on bony anatomy matching. A seroma-specific marker-based approach has the potential to improve treatment accuracy by taking the true inter

  2. Laser polarization dependence of proton emission from a thin foil target irradiated by a 70 fs, intense laser pulse

    International Nuclear Information System (INIS)

    Fukumi, A.; Nishiuchi, M.; Daido, H.; Li, Z.; Sagisaka, A.; Ogura, K.; Orimo, S.; Kado, M.; Hayashi, Y.; Mori, M.; Bulanov, S.V.; Esirkepov, T.; Nemoto, K.; Oishi, Y.; Nayuki, T.; Fujii, T.; Noda, A.; Nakamura, S.

    2005-01-01

    A study of proton emission from a 3-μm-thick Ta foil target irradiated by p-, s-, and circularly polarized laser pulses with respect to the target plane has been carried out. Protons with energies up to 880 keV were observed in the target normal direction under the irradiation by the p-polarized laser pulse, which yielded the highest efficiency for proton emission. In contrast, s- and circularly polarized laser pulses gave the maximum energies of 610 and 680 keV, respectively. The difference in the maximum energy between the p- and s-polarized cases was associated with the difference between the sheath fields estimated from electron spectra

  3. Demonstration of a neonlike argon soft-x-ray laser with a picosecond-laser-irradiated gas puff target.

    Science.gov (United States)

    Fiedorowicz, H; Bartnik, A; Dunn, J; Smith, R F; Hunter, J; Nilsen, J; Osterheld, A L; Shlyaptsev, V N

    2001-09-15

    We demonstrate a neonlike argon-ion x-ray laser, using a short-pulse laser-irradiated gas puff target. The gas puff target was formed by pulsed injection of gas from a high-pressure solenoid valve through a nozzle in the form of a narrow slit and irradiated with a combination of long, 600-ps and short, 6-ps high-power laser pulses with a total of 10 J of energy in a traveling-wave excitation scheme. Lasing was observed on the 3p (1)S(0)?3s (1)P(1) transition at 46.9 nm and the 3d (1)P(1)?3p (1)P(1) transition at 45.1 nm. A gain of 11 cm(-1) was measured on these transitions for targets up to 0.9 cm long.

  4. Transplutonium elements production program: extraction chromatographic process for plutonium irradiated targets

    International Nuclear Information System (INIS)

    Bourges, J.; Madic, C.; Koehly, G.

    1980-01-01

    The treatment of irradiated plutonium targets by extraction chromatography allowed the purification of the isotopes 243 Am and 244 Cm on the scale of few tens of grams. This process proved to be extremely simple and flexible, and yielded results which are reproducible in time. The chief advantage of the TBP process over the HDEHP process in high and medium activity conditions lies in the rapid absorption/desorption kinetics of the elements to be purified and in the separation of americium from curium, which largely offsets its lower selectivity for lanthanide elements. it is certainly possible to improve the performance of this process by: a) optimization of the characteristics of the stationary phase, b) improvement in the filling technique and in hydraulic operation of the columns, c) on-line analysis of americium (the key element in actinide/lanthanide separation) in the eluate. The application of extraction chromatography with HD(DiBM)P to the purification of 243 Am of the end of treatment makes the process more consistent, eliminates the delicate stages implemented in hot cell, and considerably improves final product quality

  5. Mitochondria-Targeted Vitamin E Protects Skin from UVB-Irradiation.

    Science.gov (United States)

    Kim, Won-Serk; Kim, Ikyon; Kim, Wang-Kyun; Choi, Ju-Yeon; Kim, Doo Yeong; Moon, Sung-Guk; Min, Hyung-Keun; Song, Min-Kyu; Sung, Jong-Hyuk

    2016-05-01

    Mitochondria-targeted vitamin E (MVE) is designed to accumulate within mitochondria and is applied to decrease mitochondrial oxidative damage. However, the protective effects of MVE in skin cells have not been identified. We investigated the protective effect of MVE against UVB in dermal fibroblasts and immortalized human keratinocyte cell line (HaCaT). In addition, we studied the wound-healing effect of MVE in animal models. We found that MVE increased the proliferation and survival of fibroblasts at low concentration (i.e., nM ranges). In addition, MVE increased collagen production and downregulated matrix metalloproteinase1. MVE also increased the proliferation and survival of HaCaT cells. UVB increased reactive oxygen species (ROS) production in fibroblasts and HaCaT cells, while MVE decreased ROS production at low concentration. In an animal experiment, MVE accelerated wound healing from laser-induced skin damage. These results collectively suggest that low dose MVE protects skin from UVB irradiation. Therefore, MVE can be developed as a cosmetic raw material.

  6. A spreadsheet to determine the volume ratio for target and breast in partial breast irradiation

    International Nuclear Information System (INIS)

    Kron, T.; Willis, D.; Miller, J.; Hubbard, P.; Oliver, M.; Chua, B.

    2009-01-01

    Full text: The technical feasibility of Partial Breast Irradiation (PBI) using external beam radiotherapy depends on the ratio between the evaluation planning target volume (PTV e val) and the whole breast volume (PBI volume ratio = PVR). We aimed to develop a simple method to determine PVR using measurements performed at the time of the planning CT scan. A PVR calculation tool was developed using a Microsoft Excel spreadsheet to determine the PTV from three orthogonal dimensions of the seroma cavity and a given margin on the CT scans. The breast volume is estimated from the separation and breast height in five equally spaced CT slices. The PTV e val and whole breast volume were determined for 29 patients from two centres using the spreadsheet calculation tool and compared to volumes delineated on computerised treatment planning systems. Both the PTV e val and whole breast volumes were underestimated by approximately 25% using the spreadsheet. The resulting PVRs were 1.05 +/- 0.35 (mean +/- 1 S D) times larger than the ones determined from planning. Estimations of the PVR using the calculation tool were achievable in around 5 minutes at the time of CT scanning and allow a prompt decision on the suitability of the patients for PBI.

  7. Clinical target volume delineation including elective nodal irradiation in preoperative and definitive radiotherapy of pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Caravatta Luciana

    2012-06-01

    Full Text Available Abstract Background Radiotherapy (RT is widely used in the treatment of pancreatic cancer. Currently, recommendation has been given for the delineation of the clinical target volume (CTV in adjuvant RT. Based on recently reviewed pathologic data, the aim of this study is to propose criteria for the CTV definition and delineation including elective nodal irradiation (ENI in the preoperative and definitive treatment of pancreatic cancer. Methods The anatomical structures of interest, as well as the abdominal vasculature were identified on intravenous contrast-enhanced CT scans of two different patients with pancreatic cancer of the head and the body. To delineate the lymph node area, a margin of 10 mm was added to the arteries. Results We proposed a set of guidelines for elective treatment of high-risk nodal areas and CTV delineation. Reference CT images were provided. Conclusions The proposed guidelines could be used for preoperative or definitive RT for carcinoma of the head and body of the pancreas. Further clinical investigations are needed to validate the defined CTVs.

  8. Melanosomes are a primary target of Q-switched ruby laser irradiation in guinea pig skin

    Energy Technology Data Exchange (ETDEWEB)

    Polla, L.L.; Margolis, R.J.; Dover, J.S.; Whitaker, D.; Murphy, G.F.; Jacques, S.L.; Anderson, R.R.

    1987-09-01

    The specific targeting of melanosomes may allow for laser therapy of pigmented cutaneous lesions. The mechanism of selective destruction of pigmented cells by various lasers, however, has not been fully clarified. Black, brown, and albino guinea pigs were exposed to optical pulses at various radiant exposure doses from a Q-switched, 40 nsec, 694 nm ruby laser. Biopsies were analyzed by light and electron microscopy (EM). Albino animals failed to develop clinical or microscopic evidence of cutaneous injury after irradiation. In both black and brown animals, the clinical threshold for gross change was 0.4 J/cm2, which produced an ash-white spot. By light microscopy, alterations appeared at 0.3 J/cm2 and included separation at the dermoepidermal junction, and the formation of vacuolated epidermal cells with a peripheral cytoplasmic condensation of pigment. By EM, enlarged melanosomes with a central lucent zone were observed within affected epidermal cells at 0.3 J/cm2. At 0.8 and 1.2 J/cm2, individual melanosomes were more intensely damaged and disruption of melanosomes deep in the hair papillae was observed. Dermal-epidermal blisters were formed precisely at the lamina lucida, leaving basal cell membranes and hemidesmosomes intact. Possible mechanisms for melanosomal injury are discussed. These observations show that the effects of the Q-switched ruby laser are melanin-specific and melanin-dependent, and may be useful in the selective destruction of pigmented as well as superficial cutaneous lesions.

  9. Time-resolved x-ray line emission studies of thermal transport in multiple beam uv-irradiated targets

    International Nuclear Information System (INIS)

    Jaanimagi, P.A.; Henke, B.L.; Delettrez, J.; Richardson, M.C.

    1984-01-01

    Thermal transport in spherical targets irradiated with multiple, nanosecond duration laser beams, has been a topic of much discussion recently. Different inferences on the level of thermal flux inhibition have been drawn from plasma velocity and x-ray spectroscopic diagnostics. We present new measurements of thermal transport on spherical targets made through time-resolved x-ray spectroscopic measurements of the progress of the ablation surface through thin layers of material on the surface of the target. These measurements, made with 6 and 12 uv (351 nm) nanosecond beams from OMEGA, will be compared to previous thermal transport measurements. Transparencies of the conference presentation are given

  10. Kink structures induced in nickel-based single crystal superalloys by high-Z element migration

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Fei; Zhang, Jianxin [Key Laboratory for Liquid Structure and Heredity of Materials, Ministry of Education, Shandong University, Jinan 250061 (China); Mao, Shengcheng [Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124 (China); Jiang, Ying [Center of Electron Microscopy and State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Feng, Qiang [National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Shen, Zhenju; Li, Jixue; Zhang, Ze [Center of Electron Microscopy and State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027 (China); Han, Xiaodong [Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing 100124 (China)

    2015-01-05

    Highlights: • Innovative kink structures generate at the γ/γ′ interfaces in the crept superalloy. • Clusters of heavy elements congregate at the apex of the kinks. • Dislocation core absorbs hexagonal structural high-Z elements. - Abstract: Here, we investigate a new type of kink structure that is found at γ/γ′ interfaces in nickel-based single crystal superalloys. We studied these structures at the atomic and elemental level using aberration corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM). The core of the dislocation absorbs high-Z elements (i.e., Co and Re) that adopt hexagonal arrangements, and it extrudes elements (i.e., Ni and Al) that adopt face centered cubic (fcc) structures. High-Z elements (i.e., Ta and W) and Cr, which is a low-Z element, are stabilized in body centered cubic (bcc) arrangements; Cr tends to behave like Re. High-Z elements, which migrate and adopt a hexagonal structure, induce kink formation at γ/γ′ interfaces. This process must be analyzed to fully understand the kinetics and dynamics of creep in nickel-based single crystal superalloys.

  11. Present status and prospect of the experimental study of QED in high Z ions

    International Nuclear Information System (INIS)

    Briand, J.P.

    1993-01-01

    I summarize in this paper the present status of our experimental knowledge on the Lamb shift of high Z hydrogenlike ions. Some tentative prospect on the future improvements with the new large accelerators and ion sources are discussed and compared with the present accuracy of QED corrections. (orig.)

  12. Measurement of prompt gamma profiles in inhomogeneous targets with a knife-edge slit camera during proton irradiation

    International Nuclear Information System (INIS)

    Priegnitz, M; Helmbrecht, S; Fiedler, F; Janssens, G; Smeets, J; Vander Stappen, F; Perali, I; Sterpin, E

    2015-01-01

    Proton and ion beam therapies become increasingly relevant in radiation therapy. To fully exploit the potential of this irradiation technique and to achieve maximum target volume conformality, the verification of particle ranges is highly desirable. Many research activities focus on the measurement of the spatial distributions of prompt gamma rays emitted during irradiation. A passively collimating knife-edge slit camera is a promising option to perform such measurements. In former publications, the feasibility of accurate detection of proton range shifts in homogeneous targets could be shown with such a camera. We present slit camera measurements of prompt gamma depth profiles in inhomogeneous targets. From real treatment plans and their underlying CTs, representative beam paths are selected and assembled as one-dimensional inhomogeneous targets built from tissue equivalent materials. These phantoms have been irradiated with monoenergetic proton pencil beams. The accuracy of range deviation estimation as well as the detectability of range shifts is investigated in different scenarios. In most cases, range deviations can be detected within less than 2 mm. In close vicinity to low-density regions, range detection is challenging. In particular, a minimum beam penetration depth of 7 mm beyond a cavity is required for reliable detection of a cavity filling with the present setup. Dedicated data post-processing methods may be capable of overcoming this limitation. (paper)

  13. Margin estimation and disturbances of irradiation field in layer-stacking carbon-ion beams for respiratory moving targets.

    Science.gov (United States)

    Tajiri, Shinya; Tashiro, Mutsumi; Mizukami, Tomohiro; Tsukishima, Chihiro; Torikoshi, Masami; Kanai, Tatsuaki

    2017-11-01

    Carbon-ion therapy by layer-stacking irradiation for static targets has been practised in clinical treatments. In order to apply this technique to a moving target, disturbances of carbon-ion dose distributions due to respiratory motion have been studied based on the measurement using a respiratory motion phantom, and the margin estimation given by the square root of the summation Internal margin2+Setup margin2 has been assessed. We assessed the volume in which the variation in the ratio of the dose for a target moving due to respiration relative to the dose for a static target was within 5%. The margins were insufficient for use with layer-stacking irradiation of a moving target, and an additional margin was required. The lateral movement of a target converts to the range variation, as the thickness of the range compensator changes with the movement of the target. Although the additional margin changes according to the shape of the ridge filter, dose uniformity of 5% can be achieved for a spherical target 93 mm in diameter when the upward range variation is limited to 5 mm and the additional margin of 2.5 mm is applied in case of our ridge filter. Dose uniformity in a clinical target largely depends on the shape of the mini-peak as well as on the bolus shape. We have shown the relationship between range variation and dose uniformity. In actual therapy, the upper limit of target movement should be considered by assessing the bolus shape. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  14. Influence of different moderator materials on characteristics of neutron fluxes generated under irradiation of lead target with proton beams

    International Nuclear Information System (INIS)

    Sosnin, A.N.; Polanski, A.; Petrochenkov, S.A.

    2002-01-01

    Neutron fields generated in extended heavy (Z ≥ 82) targets under irradiation with proton beams at energies in the range of 1 GeV are investigated. Influence of different moderators on the spectra and multiplicities of neutrons escaping the surface of the assembly consisting of a lead target (diam. 8 cm x 20 cm or diam. 8 cm x 50 cm) screened by variable thickness of polyethylene or graphite, respectively, was compared. It is shown that the effectiveness of graphite as a material used in such assemblies to moderate spallation neutrons down to thermal energies is significantly lower than that of paraffin

  15. Influence of Different Moderator Materials on Characteristics of Neutron Fluxes Generated under Irradiation of Lead Target with Proton Beams

    CERN Document Server

    Sosnin, A N; Polanski, A; Petrochenkov, S A; Golovatyuk, V M; Krivopustov, M I; Bamblevski, V P; Westmeier, W; Odoj, R; Brandt, R; Robotham, H; Hashemi-Nezhad, S R; Zamani-Valassiadou, M

    2002-01-01

    Neutron fields generated in extended heavy (Z\\geq 82) targets under irradiation with proton beams at energies in the range of 1 GeV are investigated. Influence of different moderators on the spectra and multiplicities of neutrons escaping the surface of the assembly consisting of a lead target (\\varnothing 8 cm\\times 20 cm or \\varnothing 8cm\\times 50 cm) screened by variable thickness of polyethylene or graphite, respectively, was compared in the present work. It is shown that the effectiveness of graphite as a material used in such assemblies to moderate spallation neutrons down to thermal energies is significantly lower than that of paraffin.

  16. Effect of prepulse on fast electron lateral transport at the target surface irradiated by intense femtosecond laser pulses

    International Nuclear Information System (INIS)

    Lin, X. X.; Li, Y. T.; Liu, B. C.; Liu, F.; Du, F.; Wang, S. J.; Lu, X.; Chen, L. M.; Zhang, L.; Liu, X.; Wang, J.; Liu, F.; Liu, X. L.; Wang, Z. H.; Ma, J. L.; Wei, Z. Y.; Zhang, J.

    2010-01-01

    The effects of preplasma on lateral fast electron transport at front target surface, irradiated by ultraintense (>10 18 W/cm 2 ) laser pulses, are investigated by Kα imaging technique. A large annular Kα halo with a diameter of ∼560 μm surrounding a central spot is observed. A specially designed steplike target is used to identify the possible mechanisms. It is believed that the halos are mainly generated by the lateral diffusion of fast electrons due to the electrostatic and magnetic fields in the preplasma. This is illustrated by simulated electron trajectories using a numerical model.

  17. Experimental and theoretical studies of the physical processes occurring in thin plane targets irradiated by intense X-ray pulses

    International Nuclear Information System (INIS)

    Bugrov, A. E.; Burdonskii, I. N.; Gavrilov, V. V.; Gol'tsov, A. Yu.; Grabovskii, E. V.; Efremov, V. P.; Zhuzhukalo, E. V.; Zurin, M. V.; Koval'skii, N. G.; Kondrashov, V. N.; Oleinik, G. M.; Potapenko, A. I.; Samokhin, A. A.; Smirnov, V. P.; Fortov, V. E.; Frolov, I. N.

    2007-01-01

    Results are presented from experimental and theoretical studies of the interaction of intense X-ray pulses with different types of plane targets, including low-density (∼10 mg/cm 3 ) ones, in the Angara-5-1 facility. It is found experimentally that a dense low-temperature plasma forms on the target surface before the arrival of the main heating X-ray pulse. It is demonstrated that the contrast of the X-ray pulse can be increased by placing a thin organic film between the target and the discharge gap. The expansion velocity of the plasma created on the target surface irradiated by Z-pinch-produced X rays was found to be (3-4) x 10 6 cm/s. A comparison between the simulation and experimental results confirms the validity of the physical-mathematical model used

  18. Detection of High-Z Objects using Multiple Scattering of Cosmic Ray Muons

    International Nuclear Information System (INIS)

    Hogan, Gary E.; Borozdin, Konstantin N.; Gomez, John; Morris, Christopher; Priedhorsky, William C.; Saunders, Alexander; Schultz, Larry J.; Teasdale, Margaret E.

    2004-01-01

    Detection of high-Z material hidden inside a large volume of ordinary cargo is an important and timely task given the danger associated with illegal transport of uranium and heavier elements. Existing radiography techniques are inefficient for shielded material, often expensive and involve radiation hazards, real and perceived. We recently demonstrated that radiographs can be formed using cosmic-ray muons. Here, we show that compact, high-Z objects can be detected and located in 3 dimensions with muon radiography. The natural flux of cosmic-ray muons, approximately 10,000 m-2min-1, can generate a reliable detection signal in a fraction of a minute, using large-area muon detectors as used in particle and nuclear physics

  19. A grey incidence algorithm to detect high-Z material using cosmic ray muons

    Science.gov (United States)

    He, W.; Xiao, S.; Shuai, M.; Chen, Y.; Lan, M.; Wei, M.; An, Q.; Lai, X.

    2017-10-01

    Muon scattering tomography (MST) is a method for using cosmic muons to scan cargo containers and vehicles for special nuclear materials. However, the flux of cosmic ray muons is low, in the real life application, the detection has to be done a short timescale with small numbers of muons. In this paper, we present a novel approach to detection of special nuclear material by using cosmic ray muons. We use the degree of grey incidence to distinguish typical waste fuel material, uranium, from low-Z material, medium-Z material and other high-Z materials of tungsten and lead. The result shows that using this algorithm, it is possible to detect high-Z materials with an acceptable timescale.

  20. High-z semiconductor nuclear radiation detectors for room-temperature gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Bornand, Bernard; Friant, Alain.

    1978-09-01

    A bibliographical review (182 articles of periodicals, conferences, reports, thesis and french patents) is presented, as addendum of the report CEA-BIB-210 (1974) on high-Z semiconductor compounds used as materials for the gamma and X-ray detection and spectrometry. This publication reviews issues from 1974 to 1977. References and summaries (in french) are incorporated into 182 bibliograhical notices. Index for authors, corporate authors, documents and periodicals, and subjects is included [fr

  1. Dual-energy X-ray radiography for automatic high-Z material detection

    International Nuclear Information System (INIS)

    Chen Gongyin; Bennett, Gordon; Perticone, David

    2007-01-01

    There is an urgent need for high-Z material detection in cargo. Materials with Z > 74 can indicate the presence of fissile materials or radiation shielding. Dual (high) energy X-ray material discrimination is based on the fact that different materials have different energy dependence in X-ray attenuation coefficients. This paper introduces the basic physics and analyzes the factors that affect dual-energy material discrimination performance. A detection algorithm is also discussed

  2. Possible version of the compression degradation of the thermonuclear indirect-irradiation targets at the national ignition facility and a reason for the failure of ignition

    Energy Technology Data Exchange (ETDEWEB)

    Rozanov, V. B., E-mail: rozanov@sci.lebedev.ru; Vergunova, G. A., E-mail: verg@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-01-15

    The main parameters of compression of a target and tendencies at change in the irradiation conditions are determined by analyzing the published results of experiments at the megajoule National Ignition Facility (NIF) on the compression of capsules in indirect-irradiation targets by means of the one-dimensional RADIAN program in the spherical geometry. A possible version of the “failure of ignition” of an indirect-irradiation target under the NIF conditions is attributed to radiation transfer. The application of onedimensional model to analyze the National Ignition Campaign (NIC) experiments allows identifying conditions corresponding to the future ignition regime and distinguishing them from conditions under which ignition does not occur.

  3. Damage evaluation of proton irradiated titanium deuteride thin films to be used as neutron production targets

    Science.gov (United States)

    Suarez Anzorena, Manuel; Bertolo, Alma A.; Gagetti, Leonardo; Gaviola, Pedro A.; del Grosso, Mariela F.; Kreiner, Andrés J.

    2018-06-01

    Titanium deuteride thin films have been manufactured under different conditions specified by deuterium gas pressure, substrate temperature and time. The films were characterized by different techniques to evaluate the deuterium content and the homogeneity of such films. Samples with different concentrations of deuterium, including non deuterated samples, were irradiated with a 150 keV proton beam. Both deposits, pristine and irradiated, were characterized by optical profilometry and scanning electron microscopy.

  4. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

    International Nuclear Information System (INIS)

    Kadhim, Munira A.; Lee, Ryonfa; Moore, Stephen R.; Macdonald, Denise A.; Chapman, Kim L.; Patel, Gaurang; Prise, Kevin M.

    2010-01-01

    Environmental 222 radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET α-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single 3 He 2+ particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  5. Genomic instability after targeted irradiation of human lymphocytes: Evidence for inter-individual differences under bystander conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kadhim, Munira A., E-mail: mkadhim@brookes.ac.uk [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Lee, Ryonfa [Biophysics, GSI Helmholtzzentrum fuer Schwerionenforschung GmbH, Planckstrasse 1, D-64291 Darmstadt (Germany); Moore, Stephen R.; Macdonald, Denise A. [Radiation and Genome Stability Unit, Medical Research Council, Harwell, Oxfordshire OX11 0RD (United Kingdom); Chapman, Kim L. [School of Life Sciences, Oxford Brookes University, Oxford OX3 0BP (United Kingdom); Patel, Gaurang; Prise, Kevin M. [Centre for Cancer Research and Cell Biology, Queen' s University Belfast, Belfast BT9 7BL (United Kingdom)

    2010-06-01

    Environmental {sup 222}radon exposure is a human health concern, and many studies demonstrate that very low doses of high LET {alpha}-particle irradiation initiate deleterious genetic consequences in both irradiated and non-irradiated bystander cells. One consequence, radiation-induced genomic instability (RIGI), is a hallmark of tumorigenesis and is often assessed by measuring delayed chromosomal aberrations. We utilised a technique that facilitates transient immobilization of primary lymphocytes for targeted microbeam irradiation and have reported that environmentally relevant doses, e.g. a single {sup 3}He{sup 2+} particle traversal to a single cell, are sufficient to induce RIGI. Herein we sought to determine differences in radiation response in lymphocytes isolated from five healthy male donors. Primary lymphocytes were irradiated with a single particle per cell nucleus. We found evidence for inter-individual variation in radiation response (RIGI, measured as delayed chromosome aberrations). Although this was not highly significant, it was possibly masked by high levels of intra-individual variation. While there are many studies showing a link between genetic predisposition and RIGI, there are few studies linking genetic background with bystander effects in normal human lymphocytes. In an attempt to investigate inter-individual variation in the induction of bystander effects, primary lymphocytes were irradiated with a single particle under conditions where fractions of the population were traversed. We showed a marked genotype-dependent bystander response in one donor after exposure to 15% of the population. The findings may also be regarded as a radiation-induced genotype-dependent bystander effect triggering an instability phenotype.

  6. Investigations of ultrafast charge dynamics in laser-irradiated targets by a self probing technique employing laser driven protons

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, H. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Kar, S., E-mail: s.kar@qub.ac.uk [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Cantono, G. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Department of Physics “E. Fermi”, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, Research Unit Adriano Gozzini, via G. Moruzzi 1, Pisa 56124 (Italy); Nersisyan, G. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Brauckmann, S. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany); Doria, D.; Gwynne, D. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Macchi, A. [Department of Physics “E. Fermi”, Largo B. Pontecorvo 3, 56127 Pisa (Italy); Consiglio Nazionale delle Ricerche, Istituto Nazionale di Ottica, Research Unit Adriano Gozzini, via G. Moruzzi 1, Pisa 56124 (Italy); Naughton, K. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom); Willi, O. [Institut für Laser-und Plasmaphysik, Heinrich-Heine-Universität, Düsseldorf (Germany); Lewis, C.L.S.; Borghesi, M. [School of Mathematics and Physics, Queen' s University Belfast, BT7 1NN (United Kingdom)

    2016-09-01

    The divergent and broadband proton beams produced by the target normal sheath acceleration mechanism provide the unique opportunity to probe, in a point-projection imaging scheme, the dynamics of the transient electric and magnetic fields produced during laser-plasma interactions. Commonly such experimental setup entails two intense laser beams, where the interaction produced by one beam is probed with the protons produced by the second. We present here experimental studies of the ultra-fast charge dynamics along a wire connected to laser irradiated target carried out by employing a ‘self’ proton probing arrangement – i.e. by connecting the wire to the target generating the probe protons. The experimental data shows that an electromagnetic pulse carrying a significant amount of charge is launched along the wire, which travels as a unified pulse of 10s of ps duration with a velocity close to speed of light. The experimental capabilities and the analysis procedure of this specific type of proton probing technique are discussed. - Highlights: • Prompt charging of laser irradiated target generates ultra-short EM pulses. • Its ultrafast propagation along a wire was studied by self-proton probing technique. • Self-proton probing technique is the proton probing with one laser pulse. • Pulse temporal profile and speed along the wire were measured with high resolution.

  7. From the Phenix irradiation end to the analytical results: PROFIL R target destructive characterization

    International Nuclear Information System (INIS)

    Ferlay, G.; Dancausse, J. Ph.

    2009-01-01

    In the French long-lived radionuclide (LLRN) transmutation program, several irradiation experiments were initiated in the Phenix fast neutron reactor to obtain a better understanding of the transmutation processes. The PROFIL experiments are performed in order to collect accurate information on the total capture integral cross sections of the principal heavy isotopes and some important fission products in the spectral range of fast reactors. One of the final goals is to diminish the uncertainties on the capture cross-section of the fission products involved in reactivity losses in fast reactors. This program includes two parts: PROFIL-R irradiated in a standard fast reactor spectrum and PROFIL-M irradiated in a moderated spectrum. The PROFIL-R and PROFIL-M irradiations were completed in August 2005 and May 2008, respectively. For both irradiations more than a hundred containers with isotopes of pure actinides and other elements in different chemical forms must be characterized. This raises a technical and analytical challenge: how to recover by selective dissolution less than 5 mg of isotope powder from a container with dimensions of only a few millimeters using hot cell facilities, and how to determine analytically both trace and ultra-trace elemental and isotopic compositions with sufficient accuracy to be useful for code calculations. (authors)

  8. Quality system target on a detail design activity irradiator ISG 500

    International Nuclear Information System (INIS)

    Reinhard Pardede

    2010-01-01

    Currently, an engineering team of Nuclear Equipment Engineering Center PRPN has been beening technology innovation detail design of Irradiator ISG 500, then enter continuing to a construction phase. A schedule detail design still being not finish yet. The installation of Irradiator ISG 500 will be used to preservative the result of agricultural product in Indonesia. It is known as an export commodity and row material for food. However, its quality need some improvements in order to meet internal and foreign consumer standard. To enhance a quality system in detail design phase has already used ISO 9001: 2008 on clausul-7: Product Realization-design. It also needs a radioactive regulation Bapeten-Indonesian Nuclear Energy Surveillance Agency compliance with IAEA GS-R 3: 2006 as well. Scope of activity design is Instrumentation and Control system; Mechanical- Electrical; Radiation and Safety and Dosimetry; Civil Structured; Quality Assurance and Technoeconomic. Technology Innovating be applied to achieved economics through Costumer and Market Focused. Gamma irradiation of Irradiator ISG 500 can be used to improve hygienic quality in terms of technological as well as economical aspects. Technology innovation fit with the state of the arts right now. Assessment should be done base not only internal audit but also monitoring and surveillance as well. By application of a Quality System on detail design activity hopefully to enhance quality on detail design, construction, more over irradiator operation. (author)

  9. The production of 103Pd and 109Cd from a proton irradiated tandem natAg/natAg targets

    International Nuclear Information System (INIS)

    Ineza, C.; Mphahlele, J.

    2014-01-01

    This paper describes a new method for the production of 103 Pd and 109 Cd using the 66 MeV proton beam of iThemba LABS on a tandem natural silver target (Ag/Ag). The radiochemical separation of the Pd radionuclides ( 103 Pd, 100 Pd) from the bulk nat Ag was done using a Chelex-100 chelating resin column. The recovery of 103 Pd from the irradiated nat Ag target was found to be >98 % without any Ag or Rh impurities detected. The radiochemical separation of 109 Cd from the bulk nat Ag target was done by the precipitation of Ag ions by Cu followed by the separation of 109 Cd, traces of Ag, Cu 2+ and Rh using a AG1-X10 anion exchange resin column. The recovery yield of 109 Cd was >99 % without any Ag or Rh impurities detected. (author)

  10. Neutronic analysis for the fission Mo99 production by irradiation of leu targets in TRIGA 14 MW reactor

    International Nuclear Information System (INIS)

    Dulugeac, S. D.; Mladin, M.; Budriman, A. G.

    2013-01-01

    Molybdenum production can be a solution for the future in the utilization of the Romanian TRIGA, taking into account the international market supply needs. Generally, two different techniques are available for Mo 99 production for use in medical Tc 99 generation.The first one is based on neutron irradiation of molybdenum targets of natural isotopic composition or enriched in Mo 98 . In a second process, Mo 99 is obtained as a result of the neutron induced fission of U 235 according to U 235 (n,f) Mo 99 . The objectives of the paper are related to Mo 99 production as a result of fission. Neutron physics parameters are determined and presented, such as: thermal flux axial distribution for the critical reactor at 10 MW inside the irradiation location; reactivity introduced by three Uranium foil containers; neutron fluxes and fission rates in the Uranium foils; released and deposited power in the Uranium foils; Mo 99 activity in the Uranium foils. (authors)

  11. Post-irradiation analysis of an ISOLDE lead-bismuth target: Stable and long-lived noble gas nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Leya, I., E-mail: Ingo.Leya@space.unibe.ch [University of Bern, Space Science and Planetology, Bern (Switzerland); Grimberg, A. [University of Bern, Space Science and Planetology, Bern (Switzerland); Isotope Geochemistry, ETH Zürich, Zürich (Switzerland); David, J.-C. [CEA/Saclay, Irfu/SPhN, 91191 Gif-sur-Yvette, Cedex (France); Schumann, D.; Neuhausen, J. [Paul Scherrer Institut, Villigen (Switzerland); Zanini, L. [Paul Scherrer Institut, Villigen (Switzerland); European Spallation Source ESS AB, P.O. Box 117, SE-22100 Lund (Sweden); Noah, E. [University of Geneva, Département de Physique Nucléaire et Corpusculaire, Geneve (Switzerland)

    2016-07-15

    We measured the isotopic concentrations of long-lived and stable He, Ne, Ar, Kr, and Xe isotopes in a sample from a lead-bismuth eutectic target irradiated with 1.0 and 1.4 GeV protons. Our data indicate for most noble gases nearly complete release with retention fractions in the range of percent or less. Higher retention fractions result from the decay of long-lived radioactive progenitors from groups 1, 2, or 7 of the periodic table. From the data we can calculate a retention fraction for {sup 3}H of 2–3%. For alkaline metals we find retention fractions of about 10%, 30%, and 50% for Na, Rb, and Cs, respectively. For the alkaline earth metal Ba we found complete retention. Finally, the measured Kr and Xe concentrations indicate that there was some release of the halogens Br and I during and/or after the irradiation.

  12. HTCAP: a FORTRAN IV program for calculating coated-particle operating temperatures in HFIR target irradiation experiments

    International Nuclear Information System (INIS)

    Kania, M.J.

    1976-05-01

    A description is presented of HTCAP, a computer code that calculates in-reactor operating temperatures of loose coated ThO 2 particles in the HFIR target series of irradiation tests. Three computational models are employed to determine the following: (1) fission heat generation rates, (2) capsule heat transfer analysis, and (3) maximum particle surface temperature within the design of an HT capsule. Maximum particle operating temperatures are calculated at daily intervals during each irradiation cycle. The application of HTCAP to sleeve CP-62 of HT-15 is discussed, and the results are compared with those obtained in an earlier thermal analysis on the same capsule. Agreement is generally within +-5 percent, while decreasing the computational time by more than an order of magnitude. A complete FORTRAN listing and summary of required input data are presented in appendices. Included is a listing of the input data and a tabular output from the thermal analysis of sleeve CP-62 of HT-15

  13. Increase in the temperature of a laser plasma formed by two-frequency UV - IR irradiation of metal targets

    International Nuclear Information System (INIS)

    Antipov, A A; Grasyuk, Arkadii Z; Efimovskii, S V; Kurbasov, Sergei V; Losev, Leonid L; Soskov, V I

    1998-01-01

    An experimental investigation was made of a laser plasma formed by successive irradiation of a metal target with 30-ps UV and IR laser pulses. The UV prepulse, of 266 nm wavelength, was of relatively low intensity (∼ 10 12 W cm -2 ), whereas the intensity of an IR pulse, of 10.6 μm wavelength, was considerably higher (∼3 x 10 14 W cm -2 ) and it was delayed by 0 - 6 ns (the optimal delay was 2 ns). Such two-frequency UV - IR irradiation produced a laser plasma with an electron temperature 5 times higher than that of a plasma created by singe-frequency IR pulses of the same (∼3 x 10 14 W cm -2 ) intensity. (interaction of laser radiation with matter. laser plasma)

  14. Some Notes on Neutron Up-Scattering and the Doppler-Broadening of High-Z Scattering Resonances

    Energy Technology Data Exchange (ETDEWEB)

    Parsons, Donald Kent [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-28

    When neutrons are scattered by target nuclei at elevated temperatures, it is entirely possible that the neutron will actually gain energy (i.e., up-scatter) from the interaction. This phenomenon is in addition to the more usual case of the neutron losing energy (i.e., down-scatter). Furthermore, the motion of the target nuclei can also cause extended neutron down-scattering, i.e., the neutrons can and do scatter to energies lower than predicted by the simple asymptotic models. In recent years, more attention has been given to temperature-dependent scattering cross sections for materials in neutron multiplying systems. This has led to the inclusion of neutron up-scatter in deterministic codes like Partisn and to free gas scattering models for material temperature effects in Monte Carlo codes like MCNP and cross section processing codes like NJOY. The free gas scattering models have the effect of Doppler Broadening the scattering cross section output spectra in energy and angle. The current state of Doppler-Broadening numerical techniques used at Los Alamos for scattering resonances will be reviewed, and suggestions will be made for further developments. The focus will be on the free gas scattering models currently in use and the development of new models to include high-Z resonance scattering effects. These models change the neutron up-scattering behavior.

  15. Experimental study of population inversion and spectral line broadening in a plasma containing a mixture of high Z and low Z ions

    International Nuclear Information System (INIS)

    Griem, H.R.

    1988-10-01

    In our work this past year at the University of Rochester's Laboratory for Laser Energetics we have studied laser-produced plasmas using spherical targets continuing layers of high Z and low Z materials. Our emphasis was on quantitative spectroscopy of ions in a very dense, recombining plasma. The targets used consisted of carbon-copper, carbon-gold, and aluminum-gold mixtures, instead of the originally proposed Fe or Mo mixtures with carbon. The thickness of the Cu and the Au layers were varied in order to study the effect of higher Z ions cooling the plasma. Indeed a pronounced cooling effect was observed by increasing the thickness of the Au layer in targets with Al-Au layers. Electron temperatures were studied by measuring the 1s-2p/1s 2 -1s2p line ratio of Al XIII to Al XII. Our experimental measurements, together with a collisional-radiative model and a 1-D hydrodynamic code, indicate that the electron temperature falls from 1500 eV with no gold to 950 eV with a 500 angstrom layer of gold. A detailed discussion of our results with Al-Au targets can be found in the enclosed preprint entitled Radiation Cooling in Laser-Produced Plasmas Due to High-Z Layers

  16. Arcing and rf signal generation during target irradiation by a high-energy, pulsed neutral particle beam

    International Nuclear Information System (INIS)

    Robiscoe, R.T.

    1988-02-01

    We present a theory describing the dynamics of arc discharges in bulk dielectric materials on board space-based vehicles. Such ''punch-through'' arcs can occur in target satellites irradiated by high-energy (250 MeV), pulsed (100 mA x 10 ms) neutral particle beams. We treat the arc as a capacitively limited avalanche current in the target dielectric material, and we find expressions for the arc duration, charge transport, currents, and discharge energy. These quantities are adjusted to be consistent with known scaling laws for the area of charge depleted by the arc. After a brief account of the statistical distribution of voltages at which the arc starts and stops, we calculate the signal strength and frequency spectrum of the electromagnetic radiation broadcast by the arc. We find that arcs from thick (/similar to/1 cm) targets can generate rf signals detectable up to 1000 km from the target, bu a radio receiver operating at frequency 80 MHz, bandwidth 100 kHz, and detection threshold -105 dBm. These thick-target arc signals are 10 to 20 dB above ambient noise at the receiver, and they provide target hit assessment if the signal spectrum can be sampled at several frequencies in the nominal range 30-200 MHz. Thin-target (/similar to/1 mm) arc signals are much weaker, but when they are detecable in conjunction with thick-target signals, target discrimination is possible by comparing the signal frequency spectra. 24 refs., 12 figs

  17. Search for hidden high-Z materials inside containers with the Muon Portal Project

    International Nuclear Information System (INIS)

    Rocca, P La; Bandieramonte, M; Blancato, A A; Bonanno, D; Indelicato, V; Presti, D Lo; Petta, C; Antonuccio, V; Becciani, U; Belluso, M; Billotta, S; Bonanno, G; Costa, A; Garozzo, S; Massimino, P; Belluomo, F; Fallica, G; Leonora, E; Longhitano, F; Longo, S

    2014-01-01

    The Muon Portal is a recently born project that plans to build a large area muon detector for a noninvasive inspection of shipping containers in the ports, searching for the presence of potential fissile (U, Pu) threats. The technique employed by the project is the well-known muon tomography, based on cosmic muon scattering from high-Z materials. The design and operational parameters of the muon portal under construction will be described in this paper, together with preliminary simulation and test results

  18. Search for hidden high-Z materials inside containers with the Muon Portal Project

    Science.gov (United States)

    La Rocca, P.; Antonuccio, V.; Bandieramonte, M.; Becciani, U.; Belluomo, F.; Belluso, M.; Billotta, S.; Blancato, A. A.; Bonanno, D.; Bonanno, G.; Costa, A.; Fallica, G.; Garozzo, S.; Indelicato, V.; Leonora, E.; Longhitano, F.; Longo, S.; Lo Presti, D.; Massimino, P.; Petta, C.; Pistagna, C.; Pugliatti, C.; Puglisi, M.; Randazzo, N.; Riggi, F.; Riggi, S.; Romeo, G.; Russo, G. V.; Santagati, G.; Valvo, G.; Vitello, F.; Zaia, A.; Zappalà, G.

    2014-01-01

    The Muon Portal is a recently born project that plans to build a large area muon detector for a noninvasive inspection of shipping containers in the ports, searching for the presence of potential fissile (U, Pu) threats. The technique employed by the project is the well-known muon tomography, based on cosmic muon scattering from high-Z materials. The design and operational parameters of the muon portal under construction will be described in this paper, together with preliminary simulation and test results.

  19. SCREENING OF HIGH-Z GRAINS AND RELATED PHENOMENA IN COLLOIDAL PLASMAS

    Directory of Open Access Journals (Sweden)

    O.Bystrenko

    2003-01-01

    Full Text Available Recent important results are briefly presented concerning the screening of high-Z impurities in colloidal plasmas. The review focuses on the phenomenon of nonlinear screening and its effects on the structure of colloidal plasmas, the role of trapped ions in grain screening, and the effects of strong collisions in the plasma background. It is shown that the above effects may strongly modify the properties of the grain screening giving rise to considerable deviations from the conventional Debye-Huckel theory as dependent on the physical processes in the plasma background.

  20. Interobserver variations of target volume delineation and its impact on irradiated volume in accelerated partial breast irradiation with intraoperative interstitial breast implant

    Directory of Open Access Journals (Sweden)

    Ritu Raj Upreti

    2017-02-01

    Full Text Available Purpose: To investigate the interobserver variations in delineation of lumpectomy cavity (LC and clinical target volume (CTV, and its impact on irradiated volume in accelerated partial breast irradiation using intraoperative multicatheter brachytherapy. Material and methods : Delineation of LC and CTV was done by five radiation oncologists on planning computed tomography (CT scans of 20 patients with intraoperative interstitial breast implant. Cavity visualization index (CVI, four-point index ranging from (0 = poor to (3 = excellent was created and assigned by observers for each patient. In total, 200 contours for all observers and 100 treatment plans were evaluated. Spatial concordance (conformity index, CI common , and CIgen, average shift in the center of mass (COM, and ratio of maximum and minimum volumes (V max /V min of LC and CTV were quantified among all observers and statistically analyzed. Variation in active dwell positions (0.5 cm step for each catheter, total reference air kerma (TRAK, volume enclosed by prescription isodose (V100% among observers and its spatial concordance were analyzed. Results : The mean ± SD CI common of LC and CTV was 0.54 ± 0.09, and 0.58 ± 0.08, respectively. Conformity index tends to increase, shift in COM and V max /V min decrease significantly (p < 0.05, as CVI increased. Out of total 309 catheters, 29.8% catheters had no change, 29.8% and 17.5% catheters had variations of 1 and 2 dwell positions (0.5 cm and 1 cm, respectively. 9.3% catheters shown variations ≥ 10 dwell positions (5 cm. The mean ± SD CI common of V100% was 0.75 ± 0.11. The mean observed V max /V min of prescription isodose and TRAK was 1.18 (range, 1.03 to 1.56 and 1.11 (range, 1.03 to 1.35, respectively. Conclusions : Interobserver variability in delineation of target volume was found to be significantly related to CVI. Smaller variability was observed with excellent visualization of LC. Interobserver variations showed dosimetric

  1. On the study of proton-irradiated Tellurium targets relevant for production of medical radioisotopes 123I and 124I

    International Nuclear Information System (INIS)

    Imam Kambali; Hari Suryanto; Daya Agung Sarwono; Cahyana Amiruddin

    2014-01-01

    The energy loss distribution and range of energetic proton beams in tellurium (Te) target have been simulated using the Stopping and Range of Ion in Matter (SRIM 2013) codes. The calculated data of the proton's range were then used to determine the optimum thickness of Te targets for future production of 123 I and 124 I from 123 Te(p,n) 123 I, 124 Te(p,n) 124 I and 124 Te(p,2n) 123 I nuclear reactions using the BATAN's Cs-30 cyclotron. It was found that for an incidence angle of 0° with respect to the target normal, the optimum thickness of 123 Te and 124 Te targets for 123 I production should be 644 µm and 1.8 mm respectively, whereas a 649 µm thick 124 Te target would be Required for 124 I production. In addition, the thickness should be decreased with increasing incidence angle. The EOB yield could theoretically reach up to 13.62 Ci of 123 I at proton energy of 22 Me V and beam current of 30 µA if the 124 Te is irradiated over a period of 3 hours. The theoretical EOB yield is comparable to the experimental data with accuracy within 10%. (author)

  2. High-Z plasma facing components in fusion devices: boundary conditions and operational experiences

    Science.gov (United States)

    Neu, R.

    2006-04-01

    In present day fusion devices optimization of the performance and experimental freedom motivates the use of low-Z plasma facing materials (PFMs). However, in a future fusion reactor, for economic reasons, a sufficient lifetime of the first wall components is essential. Additionally, tritium retention has to be small to meet safety requirements. Tungsten appears to be the most realistic material choice for reactor plasma facing components (PFCs) because it exhibits the lowest erosion. But besides this there are a lot of criteria which have to be fulfilled simultaneously in a reactor. Results from present day devices and from laboratory experiments confirm the advantages of high-Z PFMs but also point to operational restrictions, when using them as PFCs. These are associated with the central impurity concentration, which is determined by the sputtering yield, the penetration of the impurities and their transport within the confined plasma. The restrictions could exclude successful operation of a reactor, but concomitantly there exist remedies to ameliorate their impact. Obviously some price has to be paid in terms of reduced performance but lacking of materials or concepts which could substitute high-Z PFCs, emphasis has to be put on the development and optimization of reactor-relevant scenarios which incorporate the experiences and measures.

  3. High-Z plasma facing components in fusion devices: boundary conditions and operational experiences

    International Nuclear Information System (INIS)

    Neu, R.

    2006-01-01

    In present day fusion devices optimization of the performance and experimental freedom motivates the use of low-Z plasma facing materials (PFMs). However, in a future fusion reactor, for economic reasons, a sufficient lifetime of the first wall components is essential. Additionally, tritium retention has to be small to meet safety requirements. Tungsten appears to be the most realistic material choice for reactor plasma facing components (PFCs) because it exhibits the lowest erosion. But besides this there are a lot of criteria which have to be fulfilled simultaneously in a reactor. Results from present day devices and from laboratory experiments confirm the advantages of high-Z PFMs but also point to operational restrictions, when using them as PFCs. These are associated with the central impurity concentration, which is determined by the sputtering yield, the penetration of the impurities and their transport within the confined plasma. The restrictions could exclude successful operation of a reactor, but concomitantly there exist remedies to ameliorate their impact. Obviously some price has to be paid in terms of reduced performance but lacking of materials or concepts which could substitute high-Z PFCs, emphasis has to be put on the development and optimization of reactor-relevant scenarios which incorporate the experiences and measures

  4. High-speed readout of high-Z pixel detectors with the LAMBDA detector

    International Nuclear Information System (INIS)

    Pennicard, D.; Smoljanin, S.; Sheviakov, I.; Xia, Q.; Rothkirch, A.; Yu, Y.; Struth, B.; Hirsemann, H.; Graafsma, H.

    2014-01-01

    High-frame-rate X-ray pixel detectors make it possible to perform time-resolved experiments at synchrotron beamlines, and to make better use of these sources by shortening experiment times. LAMBDA is a photon-counting hybrid pixel detector based on the Medipix3 chip, designed to combine a small pixel size of 55 μm, a large tileable module design, high speed, and compatibility with ''high-Z'' sensors for hard X-ray detection. This technical paper focuses on LAMBDA's high-speed-readout functionality, which allows a frame rate of 2000 frames per second with no deadtime between successive images. This takes advantage of the Medipix3 chip's ''continuous read-write'' function and highly parallelised readout. The readout electronics serialise this data and send it back to a server PC over two 10 Gigabit Ethernet links. The server PC controls the detector and receives, processes and stores the data using software designed for the Tango control system. As a demonstration of high-speed readout of a high-Z sensor, a GaAs LAMBDA detector was used to make a high-speed X-ray video of a computer fan

  5. Comprehensive irradiation of head and neck cancer using conformal multisegmental fields: assessment of target coverage and noninvolved tissue sparing

    International Nuclear Information System (INIS)

    Eisbruch, Avraham; Marsh, Lon H.; Martel, Mary K.; Ship, Jonathan A.; Haken, Randall ten; Pu, Anthony T.; Fraass, Benedick A.; Lichter, Allen S.

    1998-01-01

    Purpose: Conformal treatment using static multisegmental intensity modulation was developed for patients requiring comprehensive irradiation for head and neck cancer. The major aim is sparing major salivary gland function while adequately treating the targets. To assess the adequacy of the conformal plans regarding target coverage and dose homogeneity, they were compared with standard irradiation plans. Methods and Materials: Fifteen patients with stage III/IV head and neck cancer requiring comprehensive, bilateral neck irradiation participated in this study. CT-based treatment plans included five to six nonopposed fields, each having two to four in-field segments. Fields and segments were devised using beam's eye views of the planning target volumes (PTVs), noninvolved organs, and isodose surfaces, to achieve homogeneous dose distribution that encompassed the targets and spared major salivary gland tissue. For comparison, standard three-field radiation plans were devised retrospectively for each patient, with the same CT-derived targets used for the clinical (conformal) plans. Saliva flow rates from each major salivary gland were measured before and periodically after treatment. Results: On average, the minimal dose to the primary PTVs in the conformal plans [95.2% of the prescribed dose, standard deviation (SD) 4%] was higher than in the standard plans (91%, SD 7%; p = 0.02), and target volumes receiving <95% or <90% of the prescribed dose were smaller in the conformal plans (p = 0.004 and 0.02, respectively). Similar advantages of the conformal plans compared to standard plans were found in ipsilateral jugular nodes PTV coverage. The reason for underdosing in the standard treatment plans was primarily failure of electron beams to fully encompass targets. No significant differences were found in contralateral jugular or posterior neck nodes coverage. The minimal dose to the retropharyngeal nodes was higher in the standard plans. However, all conformal plans

  6. 800-MeV proton irradiation of thorium and depleted uranium targets

    Energy Technology Data Exchange (ETDEWEB)

    Russell, G.J.; Brun, T.O.; Pitcher, E.J. [Los Alamos National Laboratory, NM (United States)] [and others

    1995-10-01

    As part of the Los Alamos Fertile-to-Fissile-Conversion (FERFICON) program in the late 1980`s, thick targets of the fertile materials thorium and depleted uranium were bombarded by 800-MeV protons to produce the fissile materials {sup 233}U and {sup 239}Pu, respectively. The amount of {sup 233}U made was determined by measuring the {sup 233}Pa activity, and the yield of {sup 239}Pu was deduced by measuring the activity of {sup 239}Np. For the thorium target, 4 spallation products and 34 fission products were also measured. For the depleted uranium target, 3 spallation products and 16 fission products were also measured. The number of fissions in each target was deduced from fission product mass-yield curves. In actuality, axial distributions of the products were measured, and the distributions were then integrated over the target volume to obtain the total number of products for each reaction.

  7. Direct flow separation strategy, to isolate no-carrier-added {sup 90}Nb from irradiated Mo or Zr targets

    Energy Technology Data Exchange (ETDEWEB)

    Radchenko, Valery; Roesch, Frank [Mainz Univ. (Germany). Inst. of Nuclear Chemistry; Filosofov, Dmitry V.; Dadakhanov, Jakhongir [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Karaivanov, Dimitar V. [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Bulgarian Academy of Sciences, Sofia (Bulgaria). Inst. for Nuclear Research and Nuclear Energy; Marinova, Atanaska [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Sofia Univ. (Bulgaria). Faculty of Chemistry and Pharmacy; Baimukhanova, Ayagoz [Joint Institute of Nuclear Research, Dubna (Russian Federation). Dzhelepov Laboratory of Nuclear Problems; Institute of Nuclear Physics of the Republic of Kazakhstan, Almaty (Kazakhstan)

    2016-11-01

    {sup 90}Nb has an intermediate half-life of 14.6 h, a high positron branching of 53% and optimal β{sup +} emission energy of only E{sub mean} 0.35 MeV per decay. These favorable characteristics suggest it may be a potential candidate for application in immuno-PET. Our recent aim was to conduct studies on distribution coefficients for Zr{sup IV} and Nb{sup V} in mixtures of HCl/H{sub 2}O{sub 2} and HCl/oxalic acid for anion exchange resin (AG 1 x 8) and UTEVA resin to develop a ''direct flow'' separation strategy for {sup 90}Nb. The direct flow concept refers to a separation accomplished using a single eluent on multiple columns, effectively streamlining the separation process and increasing the time efficiency. Finally, we also demonstrated that this separation strategy is applicable to the production of the positron emitter {sup 90}Nb via the irradiation of molybdenum targets and isolation of {sup 90}Nb from the irradiated molybdenum target.

  8. Preparation Of Phosphorus-32 (P-32) From Irradiated Target P2O5 For Therapeutic Purposes In Nuclear Medicine

    International Nuclear Information System (INIS)

    Nguyen Dang Khoa; Chu Van Khoa; Duong Van Dong

    2011-01-01

    Phosphorus-32 is produced using the nuclear reaction 31 P (n,γ) 32 P by irradiation of the phosphorus peroxide (P 2O 5) target. Phosphoric acid is prepared by the dissolution of irradiated target in 40 ml of boiling chloric acid 0.1 N. When the dissolution of phosphor peroxide is completed, the beaker is allowed to cool. 8 ml of 30% H 2 O 2 is added and refluxed for 3 h. Finally, the solution is filtered through a sintered glass filter, porosity G3 and passed into a column of cationic exchanger (Dowex-50 W-X4 preconditioned in hydrogen form) to remove metallic impurities. The effluent is collected as the stock solution. Radiochemical purity is determined by paper chromatography (radiochemical purity control) in the solvent system: Whatman No. 1 paper and the mixture of isopropyl alcohol : water : 50% trichloracetic acid : 25% NH 4 OH (75:15:10:0.3 v/v.) as a mobile phase, developing time ranged from 12 to 17 h. Radiochemical purity of phosphoric acid (H 3 32 PO 4 ) solution prepared by our method is obtained more than 99%. (author)

  9. Target-plasma production by laser irradiation of a pellet in the Baseball II-T experiment

    International Nuclear Information System (INIS)

    Damm, C.C.; Foote, J.H.; Futch, A.H.; Goodman, R.K.; Hornady, R.S.; Osher, J.E.; Porter, G.D.

    1977-01-01

    One way to generate a plasma target that can be used in conjunction with an injected neutral beam to initiate a high-energy plasma in a steady-state, magnetic-mirror field is by the laser irradiation of a solid pellet located within the confinement region. In the Lawrence Livermore Laboratory Baseball II-T experiment, a CO 2 laser was used to provide a two-sided irradiation of an ammonia pellet; the maximum laser intensity on the pellet was approximately 4 x 10 12 W/cm 2 . The 150-μm-dia pellets were guided to the laser focal spot in the Baseball II-T magnetic field using steering voltages controlled by a microcomputer-based system. Diagnostics showed complete ionization of the pellet, average ion energies in the keV range, synchronized triggering of the laser and the neutral beam, and rapid expansion of the plasma to a diameter that was a good match to the diameter of the neutral beam. Predictions obtained from the LASNEX code compared well with measured results. Although the laser-pellet approach was proven usable as a target-plasma startup system, it would be much more complicated and expensive than the method in which streaming plasma is used to trap the neutal beams

  10. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device

    Energy Technology Data Exchange (ETDEWEB)

    Zarghami, Niloufar, E-mail: nzargham@uwo.ca; Jensen, Michael D. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Talluri, Srikanth; Dick, Frederick A. [Department of Biochemistry, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Foster, Paula J. [Imaging Research Laboratories, Robarts Research Institute, 100 Perth Drive, London, Ontario N6A 5K8 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Chambers, Ann F. [Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada); Wong, Eugene [Department of Physics and Astronomy, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Medical Biophysics, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); Department of Oncology, The University of Western Ontario, 1151 Richmond Street, London, Ontario N6A 3K7 (Canada); London Regional Cancer Program, London Health Sciences Centre, 800 Commissioners Road East, London, Ontario N6A 5W9 (Canada)

    2015-11-15

    Purpose: Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. Methods: A mouse head holder was designed for a microCT couch using CAD software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. Results: Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14 ± 0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2° ± 1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. Conclusions: The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs.

  11. Technical Note: Immunohistochemical evaluation of mouse brain irradiation targeting accuracy with 3D-printed immobilization device

    International Nuclear Information System (INIS)

    Zarghami, Niloufar; Jensen, Michael D.; Talluri, Srikanth; Dick, Frederick A.; Foster, Paula J.; Chambers, Ann F.; Wong, Eugene

    2015-01-01

    Purpose: Small animal immobilization devices facilitate positioning of animals for reproducible imaging and accurate focal radiation therapy. In this study, the authors demonstrate the use of three-dimensional (3D) printing technology to fabricate a custom-designed mouse head restraint. The authors evaluate the accuracy of this device for the purpose of mouse brain irradiation. Methods: A mouse head holder was designed for a microCT couch using CAD software and printed in an acrylic based material. Ten mice received half-brain radiation while positioned in the 3D-printed head holder. Animal placement was achieved using on-board image guidance and computerized asymmetric collimators. To evaluate the precision of beam localization for half-brain irradiation, mice were sacrificed approximately 30 min after treatment and brain sections were stained for γ-H2AX, a marker for DNA breaks. The distance and angle of the γ-H2AX radiation beam border to longitudinal fissure were measured on histological samples. Animals were monitored for any possible trauma from the device. Results: Visualization of the radiation beam on ex vivo brain sections with γ-H2AX immunohistochemical staining showed a sharp radiation field within the tissue. Measurements showed a mean irradiation targeting error of 0.14 ± 0.09 mm (standard deviation). Rotation between the beam axis and mouse head was 1.2° ± 1.0° (standard deviation). The immobilization device was easily adjusted to accommodate different sizes of mice. No signs of trauma to the mice were observed from the use of tooth block and ear bars. Conclusions: The authors designed and built a novel 3D-printed mouse head holder with many desired features for accurate and reproducible radiation targeting. The 3D printing technology was found to be practical and economical for producing a small animal imaging and radiation restraint device and allows for customization for study specific needs

  12. Industrial production and purification of 32P by sulfur irradiation with partially moderated neutron fluxes and target melting

    International Nuclear Information System (INIS)

    Alanis, J.; Navarrete, M.

    2007-01-01

    Target purification of S α is carried out by distillation at 444±2 deg C under N atmosphere and diluting the vapors in CS 2 . The solution is filtered through fiberglass, Teflon and cellulose to obtain S α by CS 2 evaporation. Once 30 g of this target are irradiated with fast neutron fluxes from 4.5 to 7.4 x 10 12 n x cm -2 x s -1 from 6 to 12 hours, the nuclear reaction 32 S(n,p) 32 P takes place. So, the irradiated S α sample is placed in a Pyrex container situated inside a furnace as the most important piece of equipment in one aluminum and Lucite glove box. The distillation of irradiated sulfur takes place at 444±2 deg C under N atmosphere during 1-2 hours. The vapors are connected to a sulfur diluter containing 20% CS 2 aqueous solution, followed by an activated carbon filter and the two similar additional sulfur diluters. Once cooled, the distillation chamber keeps the radioactive, carrier-free 32 P stuck to the wall. Then 25-50 ml of 0.1N HCl acid was injected by suction and heated again at 110±2 deg C during 1 hour. The corresponding chemical reaction takes place and the labeled H 3 32 PO 4 solution is produced. In such a way, industrial production of 32 P labeled molecules has started in Mexico, with an initial production of 3700-5550 MBq per week. (author)

  13. Oscillator strength of partially ionized high-Z atom on Hartree-Fock Slater model

    International Nuclear Information System (INIS)

    Nakamura, S.; Nishikawa, T.; Takabe, H.; Mima, K.

    1991-01-01

    The Hartree-Fock Slater (HFS) model has been solved for the partially ionized gold ions generated when an intense laser light is irradiated on a gold foil target. The resultant energy levels are compared with those obtained by a simple screened hydrogenic model with l-splitting effect (SHML). It is shown that the energy levels are poorly model by SHML as the ionization level becomes higher. The resultant wave functions are used to evaluate oscillator strength of important line radiations and compared with those obtained by a simple model using hydrogenic wave functions. Its demonstrated that oscillator strength of the 4p-4d and 4d-4f lines are well modeled by the simple method, while the 4-5 transitions such as 4f-5g, 4d-5f, 4p-5d, and 4f-5p forming the so-called N-band emission are poorly modeled and HFS results less strong line emissions. (author)

  14. X-ray imaging of subsurface dynamics in high-Z materials at the Diamond Light Source

    Science.gov (United States)

    Eakins, D. E.; Chapman, D. J.

    2014-12-01

    In this paper, we describe a new approach enabling study of subsurface dynamics in high-Z materials using the unique combination of high-energy synchrotron X-rays, a hybrid bunch structure, and a new dynamic loading platform. We detail the design and operation of the purpose-built, portable small bore gas-gun, which was installed on the I12 high-energy beamline at the Diamond Light Source and used to drive compression waves into solid and porous metal targets. Using a hybrid bunch structure and broadband X-ray pulses of up to 300 keV, radiographic snapshots were captured during various dynamic deformation processes in cm-scale specimens, thereby contributing to a more complete understanding of the evolution of mesoscale damage. Importantly, we highlight strategies for overcoming the challenges associated with using high-energy X-rays, and suggest areas for improvement needed to advance dynamic imaging through large-scale samples of relevance to engineering scenarios. These preliminary measurements demonstrate the feasibility of probing highly transient phenomena using the presented methodology.

  15. X-ray imaging of subsurface dynamics in high-Z materials at the Diamond Light Source

    International Nuclear Information System (INIS)

    Eakins, D. E.; Chapman, D. J.

    2014-01-01

    In this paper, we describe a new approach enabling study of subsurface dynamics in high-Z materials using the unique combination of high-energy synchrotron X-rays, a hybrid bunch structure, and a new dynamic loading platform. We detail the design and operation of the purpose-built, portable small bore gas-gun, which was installed on the I12 high-energy beamline at the Diamond Light Source and used to drive compression waves into solid and porous metal targets. Using a hybrid bunch structure and broadband X-ray pulses of up to 300 keV, radiographic snapshots were captured during various dynamic deformation processes in cm-scale specimens, thereby contributing to a more complete understanding of the evolution of mesoscale damage. Importantly, we highlight strategies for overcoming the challenges associated with using high-energy X-rays, and suggest areas for improvement needed to advance dynamic imaging through large-scale samples of relevance to engineering scenarios. These preliminary measurements demonstrate the feasibility of probing highly transient phenomena using the presented methodology

  16. Unresolved transition array based water window soft x-ray source by laser-produced high-Z plasma

    International Nuclear Information System (INIS)

    Higashiguchi, Takeshi; Dunne, Padraig; O'Sullivan, Gerry

    2013-01-01

    We demonstrate a table-top broadband emission water window source based on laser-produced high-Z plasmas. resonance emission from multiply charged ions merges to produce intense unresolved transition arrays (UTAs) in the 2 to 4 nm region, extending below the carbon K edge (4.37 nm). Arrays resulting from n=4-n=4 transitions are overlaid with n=4-n=5 emission and shift to shorter wavelength with increasing atomic number. An outline of a microscope design for single-shot live cell imaging is proposed based on a bismuth plasma UTA source, coupled to multilayer mirror optics. At power densities available from 'table-top' solid-state lasers, comparison of emission from a number of targets has shown that 3d-4f UTA in zirconium plasmas have highest overall brightness and in an imaging system based on reflective multilayer mirrors, may, depending on bandwidth, have superior performance than either line or broader-band sources. (author)

  17. Potential for enhancing external beam radiotherapy for lung cancer using high-Z nanoparticles administered via inhalation

    Science.gov (United States)

    Hao, Yao; Altundal, Yucel; Moreau, Michele; Sajo, Erno; Kumar, Rajiv; Ngwa, Wilfred

    2015-09-01

    Nanoparticle-aided radiation therapy is emerging as a promising modality to enhance radiotherapy via the radiosensitizing action of high atomic number (Z) nanoparticles. However, the delivery of sufficiently potent concentrations of such nanoparticles to the tumor remain a challenge. This study investigates the dose enhancement to lung tumors due to high-Z nanoparticles (NPs) administered via inhalation during external beam radiotherapy. Here NPs investigated include: cisplatin nanoparticles (CNPs), carboplatin nanoparticles (CBNPs), and gold nanoparticles (GNPs). Using Monte Carlo-generated megavoltage energy spectra, a previously employed analytic method was used to estimate dose enhancement to lung tumors due to radiation-induced photoelectrons from the NPs administered via inhalation route (IR) in comparison to intravenous (IV) administration. Previous studies have indicated about 5% of FDA-approved cisplatin concentrations reach the lung via IV. Meanwhile recent experimental studies indicate that 3.5-14.6 times higher concentrations of NPs can reach the lung by IR compared to IV. Taking these into account, the dose enhancement factor (DEF) defined as the ratio of the radiotherapy dose with and without nanoparticles was calculated for a range of NPs concentrations and tumor sizes. The DEF for IR was then compared with that for IV. For IR with 3.5 times higher concentrations than IV, and 2 cm diameter tumor, clinically significant DEF values of up to 1.19, 1.26, and 1.51 were obtained for CNPs, CBNPs and GNPs. In comparison values of 1.06, 1.08, and 1.15 were obtained via IV administration. For IR with 14.6 times higher concentrations, even higher DEF values were obtained e.g. 1.81 for CNPs. Results also showed that the DEF increased with increasing field size or decreasing tumor volume, as expected. The results of this work indicate that IR administration of targeted high-Z CNPs/CBNPs/GNPs could enable clinically significant DEF to lung tumors compared to IV

  18. A high-energy electron beam ion trap for production of high-charge high-Z ions

    International Nuclear Information System (INIS)

    Knapp, D.A.; Marrs, R.E.; Elliott, S.R.; Magee, E.W.; Zasadzinski, R.

    1993-01-01

    We have developed a new high-energy electron beam ion trap, the first laboratory source of low-energy, few-electron, high-Z ions. We describe the device and report measurements of its performance, including the electron beam diameter, current density and energy, and measurements of the ionization balance for several high-Z elements in the trap. This device opens up a wide range of possible experiments in atomic physics, plasma physics, and nuclear physics. (orig.)

  19. Influences on target irradiation symmetry in CO2 laser-fusion experiments

    International Nuclear Information System (INIS)

    Carman, R.L.

    1981-01-01

    The existence of very steep density profiles and high upper shelf densities imply that the CO 2 laser deposits its energy spatially quite close to the ablation surface where calculations indicate that a high degree of symmetry must exist in order to achieve the necessary high compression ratios. Thus, energy transport provides only limited improvement in the ablative symmetry over that achieved in the irradiation symmetry. Current data suggests that a balance between radiation pressure and hydrodynamic pressure underestimates the density to which the CO 2 laser light penetrates for early times

  20. Uniform irradiation of adjustable target spots in high-power laser driver

    International Nuclear Information System (INIS)

    Jiang Xiujuan; Li Jinghui; Li Huagang; Li Yang; Lin Zunqi

    2011-01-01

    For smoothing and shaping the on-target laser patterns flexibly in high-power laser drivers, a scheme has been developed that includes a zoom lens array and two-dimensional smoothing by spectral dispersion (SSD). The size of the target pattern can be controlled handily by adjusting the focal length of the zoom lens array, while the profile of the pattern can be shaped by fine tuning the distance between the target and the focal plane of the principal focusing lens. High-frequency stripes inside the pattern caused by beamlet interference are wiped off by spectral dispersion. Detailed simulations indicate that SSD works somewhat differently for spots of different sizes. For small spots, SSD mainly smooths the intensity modulation of low-to-middle spatial frequency, while for large spots, SSD sweeps the fine speckle structure to reduce nonuniformity of middle-to-high frequency. Spatial spectra of the target patterns are given and their uniformity is evaluated.

  1. Directional enhancement of selected high-order-harmonics from intense laser irradiated blazed grating targets.

    Science.gov (United States)

    Zhang, Guobo; Chen, Min; Liu, Feng; Yuan, Xiaohui; Weng, Suming; Zheng, Jun; Ma, Yanyun; Shao, Fuqiu; Sheng, Zhengming; Zhang, Jie

    2017-10-02

    Relativistically intense laser solid target interaction has been proved to be a promising way to generate high-order harmonics, which can be used to diagnose ultrafast phenomena. However, their emission direction and spectra still lack tunability. Based upon two-dimensional particle-in-cell simulations, we show that directional enhancement of selected high-order-harmonics can be realized using blazed grating targets. Such targets can select harmonics with frequencies being integer times of the grating frequency. Meanwhile, the radiation intensity and emission area of the harmonics are increased. The emission direction is controlled by tailoring the local blazed structure. Theoretical and electron dynamics analysis for harmonics generation, selection and directional enhancement from the interaction between multi-cycle laser and grating target are carried out. These studies will benefit the generation and application of laser plasma-based high order harmonics.

  2. QED effects in high-Z atoms; three-body potentials

    International Nuclear Information System (INIS)

    Zygelman, B.

    1983-01-01

    Electromagnetic three-body potentials were first studied by Primakoff and Holstein. Later, Chamugan and Schweber rederived these potentials and pointed out that they might be important in highly relativistic systems, however, their formulation was basically nonrelativistic. Mittleman, in a series of papers, constructed configuration space equations that included three-body potentials. His derivation started from first principles i.e. QED, and the resulting three-body potentials are more general than the Primakoff-Holstein potentials. In this thesis the contribution to the binding energy of a simple high-Z ion from the three-body potentials is calculated. In addition, the nature and structure of these potentials in greater detail are studied. Some ambiguities that arise when the transition from Fock to configuration space is made are studied in detail

  3. Discrimination of high-Z materials in concrete-filled containers using muon scattering tomography

    Science.gov (United States)

    Frazão, L.; Velthuis, J.; Thomay, C.; Steer, C.

    2016-07-01

    An analysis method of identifying materials using muon scattering tomography is presented, which uses previous knowledge of the position of high-Z objects inside a container and distinguishes them from similar materials. In particular, simulations were performed in order to distinguish a block of Uranium from blocks of Lead and Tungsten of the same size, inside a concrete-filled drum. The results show that, knowing the shape and position from previous analysis, it is possible to distinguish 5 × 5 × 5 cm3 blocks of these materials with about 4h of muon exposure, down to 2 × 2 × 2 cm3 blocks with 70h of data using multivariate analysis (MVA). MVA uses several variables, but it does not benefit the discrimination over a simpler method using only the scatter angles. This indicates that the majority of discrimination is provided by the angular information. Momentum information is shown to provide no benefits in material discrimination.

  4. Results of four one-day electron-accelerator irradiations of enriched Mo-100 targets for the production of Mo-99

    Energy Technology Data Exchange (ETDEWEB)

    Chemerisov, S. [Argonne National Lab. (ANL), Argonne, IL (United States); Bailey, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Heltemes, T. [Argonne National Lab. (ANL), Argonne, IL (United States); Jonah, C. [Argonne National Lab. (ANL), Argonne, IL (United States); Gromov, R. [Argonne National Lab. (ANL), Argonne, IL (United States); Makarashvili, V. [Argonne National Lab. (ANL), Argonne, IL (United States); Tkac, P. [Argonne National Lab. (ANL), Argonne, IL (United States); Rotsch, D. [Argonne National Lab. (ANL), Argonne, IL (United States); Virgo, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, G. F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-10-01

    A series of four one-day irradiations was conducted with 100Mo-enriched disk targets. After irradiation, the enriched disks were removed from the target and dissolved. The resulting solution was processed using a NorthStar RadioGenix™ 99mTc generator either at Argonne National Laboratory or at the NorthStar Medical Radioisotopes facility. Runs on the RadioGenix system produced inconsistent analytical results for 99mTc in the Tc/Mo solution. These inconsistencies were attributed to the impurities in the solution or improper column packing. During the irradiations, the performance of the optic transitional radiation (OTR) and infrared cameras was tested in high radiation field. The OTR cameras survived all irradiations, while the IR cameras failed every time. The addition of X-ray and neutron shielding improved camera survivability and decreased the number of upsets.

  5. Targeted heavy-ion microbeam irradiation of the embryo but not yolk in the diapause-terminated egg of the silkworm, bombyx mori, induces the somatic mutation

    International Nuclear Information System (INIS)

    Furusawa, Toshiharu; Fukamoto, Kana; Sakashita, Tetsuya; Funayama, Tomoo; Kobayashi, Yasuhiko; Kakizaki, Takehiko; Wada, Seiichi; Hamada, Nobuyuki; Suzuki, Hiromi; Ishioka, Noriaki; Nagaoka, Shunji

    2009-01-01

    Using heavy-ion microbeam, we report target irradiation of selected compartments within the diapause-terminated egg and its mutational consequences in the silkworm, Bombyx mori. On one hand, carbon-ion exposure of embryo to 0.5-6 Gy increased the somatic mutation frequency, suggesting targeted radiation effects. On the other, such increases were not observed when yolk was targeted, suggesting a lack of nontargeted bystander effect. (author)

  6. Green methods for the radiochemical separations of no-carrier-added 61Cu, 62Zn from 7Li irradiated cobalt target

    International Nuclear Information System (INIS)

    Moumita Maiti; Kaustab Ghosh; Susanta Lahiri

    2015-01-01

    A nat Co target was irradiated with 47 MeV 7 Li beam to produce no-carrier-added 61 Cu, 62 Zn in the target matrix. Two new green radiochemical methods were developed for separation of 61 Cu and 62 Zn from the target matrix, (i) liquid-liquid extraction (LLX) technique using room temperature ionic liquid (RTIL) 1-butyl-3-methylimidazolium hexafluorophosphate ([C 4 mim][PF 6 ]) and ammonium pyrrolidinedithiocarbamate (APDC) (ii) adsorption on calcium alginate beads. (author)

  7. Magnetic collimation of fast electrons in specially engineered targets irradiated by ultraintense laser pulses

    International Nuclear Information System (INIS)

    Cai Hongbo; Zhu Shaoping; Wu Sizhong; Chen Mo; Zhou Cangtao; He, X. T.; Yu Wei; Nagatomo, Hideo

    2011-01-01

    The efficient magnetic collimation of fast electron flow transporting in overdense plasmas is investigated with two-dimensional collisional particle-in-cell numerical simulations. It is found that the specially engineered targets exhibiting either high-resistivity-core-low-resistivity-cladding structure or low-density-core-high-density-cladding structure can collimate fast electrons. Two main mechanisms to generate collimating magnetic fields are found. In high-resistivity-core-low-resistivity-cladding structure targets, the magnetic field at the interfaces is generated by the gradients of the resistivity and fast electron current, while in low-density-core-high-density-cladding structure targets, the magnetic field is generated by the rapid changing of the flow velocity of the background electrons in transverse direction (perpendicular to the flow velocity) caused by the density jump. The dependences of the maximal magnetic field on the incident laser intensity and plasma density, which are studied by numerical simulations, are supported by our analytical calculations.

  8. Temperature effect of irradiated target surface on distribution of nanoparticles formed by implantation

    CERN Document Server

    Stepanov, A L; Popok, V N

    2001-01-01

    The composition layers, containing the metal nanoparticles, synthesized thorough implantation of the Ag sup + ions with the energy of 60 keV and the dose of 3 x 10 sup 1 sup 6 ion/cm sup 2 into the sodium-calcium silicate glass by the ion current of 3 mu A/cm sup 2 and the sublayer temperature of 35 deg C are studied. The obtained implantation results are analyzed in dependence on the temperature effects, developing for the glass samples of various thickness. The data on the silver distribution, the metal nanoparticles formation and growth by depth are obtained from the optical reflection spectra. It is demonstrated that minor changes in the surface temperature of the irradiated glass sublayer lead to noticeable diversities in the regularities of the nanoparticles formation in the sample volume

  9. Designing Targets for Elective Nodal Irradiation in Lung Cancer Radiotherapy: A Planning Study

    International Nuclear Information System (INIS)

    Kepka, Lucyna; Tatro, Daniel; Moran, Jean M.; Quint, Leslie E.; Hayman, James A.; Ten Haken, Randall K.; Kong Fengming

    2009-01-01

    Purpose: To assess doses received by mediastinal and hilar lymph node stations (LNS) delineated according to published recommendations when 'standard' two-dimensional (2D) elective fields are applied and to assess doses to critical structures when fields are designed using 2D and three-dimensional (3D) treatment planning for elective irradiation. Methods and Materials: LNS were delineated on axial CT scans according to existing recommendations. For each case and tumor location, 2D anteroposterior-posteroanterior (AP-PA) elective fields were applied using the AP-PA CT topograms. From the 2D portal fields, 3D dose distributions were then calculated to particular LNS. Next, 3D plans were prepared for elective nodal irradiation for tumors of different lobes. Doses for critical structures were compared for 2D and 3D plans. Results: LNS 1/2R, 1/2L, 3A, 3P, 5, 6, and 8 were not adequately covered in a substantial part of plans by standard 2D portals when guidelines for delineation were strictly followed. The magnitude of the lack of coverage increased with margin application. There was a trend for a higher yet probably still safe dose delivered to lung for 3D plans compared with 2D plans with a prescription dose of 45 Gy. Conclusions: 2D fields did not entirely cover LNS delineated according to the recommendations for 3D techniques. A strict adherence to these guidelines may lead to larger portals than traditionally constructed using 2D methods. Some modifications for clinical implementation are discussed.

  10. Target irradiation induced bystander effects between stem-like and non stem-like cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yu [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Space Radiation Research Unit, International Open Laboratory, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Kobayashi, Alisa [Space Radiation Research Unit, International Open Laboratory, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Department of Technical Support and Development, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Maeda, Takeshi [Department of Technical Support and Development, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Fu, Qibin [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Oikawa, Masakazu [Department of Technical Support and Development, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Yang, Gen, E-mail: gen.yang@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Space Radiation Research Unit, International Open Laboratory, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Konishi, Teruaki, E-mail: tkonishi@nirs.go.jp [Space Radiation Research Unit, International Open Laboratory, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Department of Technical Support and Development, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Uchihori, Yukio [Space Radiation Research Unit, International Open Laboratory, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); Department of Technical Support and Development, National Institute of Radiological Sciences, 4-9-1 Inage-ku, Chiba 263-8555 (Japan); and others

    2015-03-15

    Highlights: • Existence of radiation induced bystander effects (RIBE) between cancer stem-like cells (CSCs) and non stem-like cancer cells (NSCCs) in human fibrosarcoma HT1080 cells. • Existence of significant difference in generation and response of bystander signals between CSCs and NSCCs. • CSCs are significantly less sensitive to NO scavenger than that of NSCCs in terms of DNA double strand breaks induced by RIBE. - Abstract: Tumors are heterogeneous in nature and consist of multiple cell types. Among them, cancer stem-like cells (CSCs) are suggested to be the principal cause of tumor metastasis, resistance and recurrence. Therefore, understanding the behavior of CSCs in direct and indirect irradiations is crucial for clinical radiotherapy. Here, the CSCs and their counterpart non stem-like cancer cells (NSCCs) in human HT1080 fibrosarcoma cell line were sorted and labeled, then the two cell subtypes were mixed together and chosen separately to be irradiated via a proton microbeam. The radiation-induced bystander effect (RIBE) between the CSCs and NSCCs was measured by imaging 53BP1 foci, a widely used indicator for DNA double strand break (DSB). CSCs were found to be less active than NSCCs in both the generation and the response of bystander signals. Moreover, the nitric oxide (NO) scavenger c-PTIO can effectively alleviate the bystander effect in bystander NSCCs but not in bystander CSCs, indicating a difference of the two cell subtypes in NO signal response. To our knowledge, this is the first report shedding light on the RIBE between CSCs and NSCCs, which might contribute to a further understanding of the out-of-field effect in cancer radiotherapy.

  11. Target irradiation induced bystander effects between stem-like and non stem-like cancer cells

    International Nuclear Information System (INIS)

    Liu, Yu; Kobayashi, Alisa; Maeda, Takeshi; Fu, Qibin; Oikawa, Masakazu; Yang, Gen; Konishi, Teruaki; Uchihori, Yukio

    2015-01-01

    Highlights: • Existence of radiation induced bystander effects (RIBE) between cancer stem-like cells (CSCs) and non stem-like cancer cells (NSCCs) in human fibrosarcoma HT1080 cells. • Existence of significant difference in generation and response of bystander signals between CSCs and NSCCs. • CSCs are significantly less sensitive to NO scavenger than that of NSCCs in terms of DNA double strand breaks induced by RIBE. - Abstract: Tumors are heterogeneous in nature and consist of multiple cell types. Among them, cancer stem-like cells (CSCs) are suggested to be the principal cause of tumor metastasis, resistance and recurrence. Therefore, understanding the behavior of CSCs in direct and indirect irradiations is crucial for clinical radiotherapy. Here, the CSCs and their counterpart non stem-like cancer cells (NSCCs) in human HT1080 fibrosarcoma cell line were sorted and labeled, then the two cell subtypes were mixed together and chosen separately to be irradiated via a proton microbeam. The radiation-induced bystander effect (RIBE) between the CSCs and NSCCs was measured by imaging 53BP1 foci, a widely used indicator for DNA double strand break (DSB). CSCs were found to be less active than NSCCs in both the generation and the response of bystander signals. Moreover, the nitric oxide (NO) scavenger c-PTIO can effectively alleviate the bystander effect in bystander NSCCs but not in bystander CSCs, indicating a difference of the two cell subtypes in NO signal response. To our knowledge, this is the first report shedding light on the RIBE between CSCs and NSCCs, which might contribute to a further understanding of the out-of-field effect in cancer radiotherapy

  12. Secondary neutron production from thick Pb target by light particle irradiation

    CERN Document Server

    Adloff, J C; Debeauvais, M; Fernández, F; Krivopustov, M; Kulakov, B A; Sosnin, A; Zamani, M

    1999-01-01

    Neutron multiplicities from spallation neutron sources were measured by Solid State Nuclear Track Detectors. Light particles as protons, deuterons and alphas in the GeV range were used on Pb targets. For neutron thermalization the targets were covered by 6 cm paraffin moderator. Neutron multiplicity distributions were studied inside and on the moderator surface. Comparison of SSNTDs results were made for thermal-epithermal neutrons with sup 1 sup 3 sup 9 La activation method as well as with Dubna DCM/CEM code. Discussion including previous sup 1 sup 2 C results are given.

  13. Proton radiography of intense-laser-irradiated wire-attached cone targets

    International Nuclear Information System (INIS)

    Yabuuchi, T.; Sawada, H.; Bartal, T.; Beg, F.N.; Batani, D.; Gizzi, L.A.; Key, M.H.; Mackinnon, A.J.; McLean, H.S.; Patel, P.K.; Norreys, P.A.; Spindloe, C.; Stephens, R.B.; Wei, M.S.; Theobald, W.

    2011-01-01

    Measurements of extreme electrostatic and magnetic fields are of interest for the study of high-energy-density plasmas. Results of proton deflectometry of cone-wire targets that are of interest to fast-ignition inertial confinement fusion are presented. (authors)

  14. Target irradiation facility and targetry development at 160 MeV proton beam of Moscow linac

    CERN Document Server

    Zhuikov, B L; Konyakhin, N A; Vincent, J

    1999-01-01

    A facility has been built and successfully operated with the 160 MeV proton beam of Moscow Meson factory LINAC, Institute for Nuclear Research (INR) of Russian Academy of Science, Troitsk. The facility was created for various isotope production goals as well as for fundamental nuclear investigations at high intensity beam (100 mu A and more). An important part of the facility targetry system is a high-intensity beam monitoring collimator device. Measurements of the temperature distribution between collimator sectors, cooling water flow and temperature, and the beam current, provide an opportunity to compute beam losses and beam position. The target holder design allows easy insertion by manipulator and simultaneous bombardment of several different targets of various types and forms, and variation of proton energy on each target over a wide range below 160 MeV. The main target utilized for commercial sup 8 sup 2 Sr isotope production is metallic rubidium in a stainless-steel container. A regular wet chemistry ...

  15. Waste Treatment of Acidic Solutions from the Dissolution of Irradiated LEU Targets for 99-Mo Production

    Energy Technology Data Exchange (ETDEWEB)

    Bakel, Allen J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Conner, Cliff [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2016-10-01

    One of the missions of the Reduced Enrichment for Research and Test Reactors (RERTR) program (and now the National Nuclear Security Administrations Material Management and Minimization program) is to facilitate the use of low enriched uranium (LEU) targets for 99Mo production. The conversion from highly enriched uranium (HEU) to LEU targets will require five to six times more uranium to produce an equivalent amount of 99Mo. The work discussed here addresses the technical challenges encountered in the treatment of uranyl nitrate hexahydrate (UNH)/nitric acid solutions remaining after the dissolution of LEU targets. Specifically, the focus of this work is the calcination of the uranium waste from 99Mo production using LEU foil targets and the Modified Cintichem Process. Work with our calciner system showed that high furnace temperature, a large vent tube, and a mechanical shield are beneficial for calciner operation. One- and two-step direct calcination processes were evaluated. The high-temperature one-step process led to contamination of the calciner system. The two-step direct calcination process operated stably and resulted in a relatively large amount of material in the calciner cup. Chemically assisted calcination using peroxide was rejected for further work due to the difficulty in handling the products. Chemically assisted calcination using formic acid was rejected due to unstable operation. Chemically assisted calcination using oxalic acid was recommended, although a better understanding of its chemistry is needed. Overall, this work showed that the two-step direct calcination and the in-cup oxalic acid processes are the best approaches for the treatment of the UNH/nitric acid waste solutions remaining from dissolution of LEU targets for 99Mo production.

  16. On the empirical determination of positron trapping coefficient at nano-scale helium bubbles in steels irradiated in spallation target

    Science.gov (United States)

    Krsjak, Vladimir; Kuriplach, Jan; Vieh, Christiane; Peng, Lei; Dai, Yong

    2018-06-01

    In the present work, the specific positron trapping rate of small helium bubbles was empirically derived from positron annihilation lifetime spectroscopy (PALS) and transmission electron microscopy (TEM) studies of Fe9Cr martensitic steels. Both techniques are well known to be sensitive to nanometer-sized helium-filled cavities induced during irradiation in a mixed proton-neutron spectrum of spallation target. Complementary TEM and PALS studies show that positrons are being trapped to these defects at a rate of 1.2 ± 0.8 × 10-14 m3s-1. This suggests that helium bubbles in ferritic/martensitic steels are attractive traps for positrons comparable to mono-vacancies and quantitative analysis of the bubbles by PALS technique is plausible.

  17. High-temperature method of rapid separation of In-111 from irradiated silver targets

    International Nuclear Information System (INIS)

    Mazgaj, Z.; Kolaczkowski, A.; Mikulski, J.; Novgorodov, A.F.; Zielinski, A.; Joint Inst. for Nuclear Research, Dubna

    1990-01-01

    A high-temperature method of separation of In-111 from α-particle activated silver targets was developed. The separation is carried out under reduced pressure, in the atmosphere of HCl and H 2 O vapours. Indium-111, adsorbed on a quartz collector, is washed out quantitatively with 0.1 N HCl. The contaminant, Cd-109 (product of decay of In-109), is removed from the preparation by means of ion-exchange chromatography. 4 tabs., 6 refs. (author)

  18. Separation of carrier-free 181Re produced in 16O-irradiated thulium target

    International Nuclear Information System (INIS)

    Lahiri, Susanta; Mukhopadhyay, Krishnendu; Banerjee, Kakoli; Ramaswami, A.; Manohar, S.B.

    2001-01-01

    Heavy ion activation of natural Tm 2 O 3 with 90 MeV 16 O beam results in the formation of carrier-free short-lived 181 Ir and 181 Os which ultimately decay out to 181 Re in the matrix. The liquid cation exchanger, HDEHP, has effectively been utilized as an extractant for quantitative separation of bulk thulium target matrix from carrier-free rhenium radionuclide

  19. Suprathermal-electron generation, transport, and deposition in CO2-laser-irradiated targets

    International Nuclear Information System (INIS)

    Hauer, A.; Goldman, R.; Kristal, R.

    1982-01-01

    Experiments on both axial and lateral energy transport and deposition in spherical targets are described. A variety of diagnostics have been used to measure hot-electron transport and deposition including bremsstrahlung and inner-shell radiation and soft x-ray temperature measurements. Self-generated electric and magnetic fields play an important role in the transport and deposition of the hot electrons. In some cases distinct patterns of surface deposition consistent with magnetic-field configurations have been observed

  20. Targeted bone marrow irradiation in the conditioning of high-risk leukaemia prior to stem cell transplantation

    International Nuclear Information System (INIS)

    Reske, S.N.; Buchmann, I.; Seitz, U.; Glatting, G.; Neumaier, B.; Kotzerke, J.; Buck, A.; Martin, H.; Bergmann, L.

    2001-01-01

    Disease recurrence following stem cell transplantation (SCT) remains a major problem. Despite the sensitivity of leukaemias to chemotherapy and irradiation, conventional conditioning before SCT is limited by significant organ toxicity. Targeted irradiation of bone marrow and spleen by radioimmunotherapy may provide considerable dose escalation, with limited toxicity to non-target organs. In this study, 27 patients with high-risk or relapsing leukaemia were treated with rhenium-188-labelled CD66a,b,c,e radioimmunoconjugates ( 188 Re-mAb) specific for normal bone marrow in addition to conventional conditioning with high-dose chemotherapy and 12 Gy total body irradiation prior to SCT. A mean activity of 10.2±2.1 (range 6.9-15.8) GBq 188 Re-mAb was administered intravenously. Acute side-effects were assessed according to the CTC classification and patient outcome was determined. Mean radiation doses (Gy; range in parentheses) to relevant organs and whole body were as follows: 13.1 (6.5-22) to bone marrow, 11.6 (1.7-31.1) to spleen, 5.0 (2.0-11.7) to liver, 7.0 (2.3-11.6) to kidneys, 0.7 (0.3-1.3) to lungs and 1.4 (0.8-2.1) to the whole body. Stem cells engrafted in all patients within 9-18 days post SCT. Acute organ toxicity of grade II or less was observed. During follow-up for 25.4±5.3 (range 18-34) months, 4/27 (15%) patients died from relapse, and 9/27 (33%) from transplantation-related complications. Fourteen patients (52%) are still alive and in ongoing complete clinical remission. Radioimmunotherapy with the bone marrow-seeking 188 Re-labelled CD66 mAb can double the dose to bone marrow and spleen without undue extramedullary acute organ toxicity, when given in addition to high-dose chemotherapy and 12 Gy TBI before allogeneic SCT. This intensified conditioning regimen may reduce the relapse rate of high-risk leukaemia. (orig.)

  1. Study of intense pulse irradiation effects on silicon targets considered as ground matter for optical detectors; Etude des effets d`irradiations pulsees intenses sur des cibles de silicium considere en tant que materiau de base pour detecteurs optiques

    Energy Technology Data Exchange (ETDEWEB)

    Muller, O

    1994-12-01

    This study aim was centered on morphological and structural alterations induced by laser irradiation on silicon targets considered as ground matter for optical detectors. First we recalled the main high light intensity effects on the condensed matter. Then we presented the experimental aspects. The experimental studies were achieved on two sample types: SiO{sub 2}/Si and Si. Two topics were studied: the defect chronology according to wavelength and pulse length, and the crystalline quality as well as the structure defects of irradiated zones by Raman spectroscopy. Finally, irradiation of Si targets by intense pulsed beams may lead to material fusion. This phenomenon is particularly easy when the material is absorbent, when the pulse is short and when the material is superficially oxidized. (MML). 204 refs., 93 figs., 21 tabs., 1 appendix.

  2. Prediction of production of {sup 22}Na in a gas-cell target irradiated by protons using Monte Carlo tracking

    Energy Technology Data Exchange (ETDEWEB)

    Eslami, M., E-mail: mohammad.eslami25@yahoo.com [Department of Physics, Faculty of Science, University of Zanjan, Zengan (Zanjan) (Iran, Islamic Republic of); Kakavand, T. [Department of Physics, Faculty of Science, University of Zanjan, Zengan (Zanjan) (Iran, Islamic Republic of); Department of Physics, Faculty of Science, Imam Khomeini International University, Qazvin (Iran, Islamic Republic of); Mirzaii, M.; Rajabifar, S. [Agricultural, Medical and Industrial Research School, Nuclear Science and Technology Research Institute, AEOI, Karaj (Iran, Islamic Republic of)

    2015-01-01

    Highlights: • Angular distribution of the proton beam in a gaseous environment. • Particle energy distribution profile and proton flux within gas-cell target with MCNPX. • Detection of the residual nuclei during the nuclear reactions. • Estimation of production yield for {sup 22,nat}Ne(p,x){sup 22}Na reactions. - Abstract: The {sup 22}Ne(p,n){sup 22}Na is an optimal reaction for the cyclotron production of {sup 22}Na. This work tends to monitor the proton induced production of {sup 22}Na in a gas-cell target, containing natural and enriched neon gas, using Monte Carlo method. The excitation functions of reactions are calculated by both TALYS-1.6 and ALICE/ASH codes and then the optimum energy range of projectile for the high yield production is selected. A free gaseous environment of neon at a particular pressure and temperature is prearranged and the proton beam is transported within it using Monte Carlo codes MCNPX and SRIM. The beam monitoring performed by each of these codes indicates that the gas-cell has to be designed as conical frustum to reach desired interactions. The MCNPX is also employed to calculate the energy distribution of proton in the designed target and estimation of the residual nuclei during irradiation. The production yield of {sup 22}Na in {sup 22}Ne(p,n){sup 22}Na and {sup nat}Ne(p,x){sup 22}Na reactions are estimated and it shows a good agreement with the experimental results. The results demonstrate that Monte Carlo makes available a beneficial manner to design and optimize the gas targets as well as calibration of detectors, which can be used for the radionuclide production purposes.

  3. Two-dimensional study of shock breakout at the rear face of laser irradiated metallic targets

    Energy Technology Data Exchange (ETDEWEB)

    Cottet, F.; Marty, L.; Hallouin, M.; Romain, J.P.; Virmont, J.; Fabbro, R.; Faral, B.

    1988-11-01

    The two-dimensional propagation dynamics of laser-driven shock waves in solids is studied through the analysis of the shock breakout at the rear face of the target for a set of materials and laser intensities. The laser shock simulations were carried out by means of a two-dimensional hydrodynamics code in which the laser-ablation pressure is replaced by an equivalent pressure pulse. It is shown that the two-dimensional code is a very useful tool to analyze laser-shock experiments where two-dimensional effects arise from a finite laser-spot size or a heterogeneous energy deposition.

  4. Two-dimensional study of shock breakout at the rear face of laser irradiated metallic targets

    International Nuclear Information System (INIS)

    Cottet, F.; Marty, L.; Hallouin, M.; Romain, J.P.; Virmont, J.; Fabbro, R.; Faral, B.

    1988-01-01

    The two-dimensional propagation dynamics of laser-driven shock waves in solids is studied through the analysis of the shock breakout at the rear face of the target for a set of materials and laser intensities. The laser shock simulations were carried out by means of a two-dimensional hydrodynamics code in which the laser-ablation pressure is replaced by an equivalent pressure pulse. It is shown that the two-dimensional code is a very useful tool to analyze laser-shock experiments where two-dimensional effects arise from a finite laser-spot size or a heterogeneous energy deposition

  5. Temporal dependence of the mass ablation rate in uv irradiated spherical targets

    International Nuclear Information System (INIS)

    Delettrez, J.; Jaanimagi, P.A.; Henke, B.L.; Richardson, M.C.

    1985-01-01

    In this talk, measurements of thermal transport in spherical geometry using time-resolved x-ray spectroscopy are presented. The time dependence of the mass ablation rate (m) is determined by following the progress of the ablation surface through thin layers of material embedded at various depths below the surface of the target. These measurements made with 6, 12 and 24 uv (351 nm) beams from OMEGA are compared to previous thermal transport data and are in qualitative agreement with detailed LILAC hydrodynamic code simulations which predict a sharp decrease in m after the peak of the laser pulse. Viewgraphs of the talk comprise the report

  6. Three-dimensional intrafractional internal target motions in accelerated partial breast irradiation using three-dimensional conformal external beam radiotherapy.

    Science.gov (United States)

    Hirata, Kimiko; Yoshimura, Michio; Mukumoto, Nobutaka; Nakamura, Mitsuhiro; Inoue, Minoru; Sasaki, Makoto; Fujimoto, Takahiro; Yano, Shinsuke; Nakata, Manabu; Mizowaki, Takashi; Hiraoka, Masahiro

    2017-07-01

    We evaluated three-dimensional intrafractional target motion, divided into respiratory-induced motion and baseline drift, in accelerated partial breast irradiation (APBI). Paired fluoroscopic images were acquired simultaneously using orthogonal kV X-ray imaging systems at pre- and post-treatment for 23 patients who underwent APBI with external beam radiotherapy. The internal target motion was calculated from the surgical clips placed around the tumour cavity. The peak-to-peak respiratory-induced motions ranged from 0.6 to 1.5mm in all directions. A systematic baseline drift of 1.5mm towards the posterior direction and a random baseline drift of 0.3mm in the lateral-medial and cranial-caudal directions were observed. The baseline for an outer tumour cavity drifted towards the lateral and posterior directions, and that for an upper tumour cavity drifted towards the cranial direction. Moderate correlations were observed between the posterior baseline drift and the patients' physical characteristics. The posterior margin for intrafractional uncertainties was larger than 5mm in patients with greater fat thickness due to the baseline drift. The magnitude of the intrafractional motion was not uniform according to the direction, patients' physical characteristics, or tumour cavity location due to the baseline drift. Therefore, the intrafractional systematic movement should be properly managed. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Physico-chemical characterization of terbium-161-chloride (161TbCl3) radioisotope from irradiated natural gadolinium oxide target

    International Nuclear Information System (INIS)

    Azmairit Aziz; Nana Suherman

    2015-01-01

    Currently cancer patients are increasing every year in Indonesia and become the third leading cause of death after heart disease and high blood pressure. Terbium-161 ( 161 Tb) is a low β- emitter (E β - = 0.155 MeV, T 1/2 = 6.9 d) and very similar to 177 Lu in terms of half-life, E β - energy and chemical properties.However, 161 Tb also ejects internal conversion electrons and Auger electrons which can provide a greater therapeutic effect than 177 Lu. Radioisotope of 161 Tb can be produced as a carrier-free for use in labeling of biomolecules as a targeted radiopharmaceutical for cancer therapy. 161 Tb was obtained through 160 Gd(n,γ) 161 Tb nuclear reaction by thermal neutron bombardment on 100 mg of natural gadolinium oxide target in RSG-G.A. Siwabessy at a thermal neutron flux of ~10 14 n.cm -2 .s -1 and followed by radiochemical separation of 161 Tb from Gd isotopes using extraction chromatography method. The physico-chemical characterization of 161 TbCl 3 solution was studied by determination of its radionuclide purity by means of a γ-rays spectrometry with HP-Ge detector coupled to a multichannel analyzer (MCA). Radiochemical purity was determined using paper chromatography and paper electrophoresis methods. The results showed that 161 TbCl 3 radioisotope has a pH of 2, radiochemical purity of 99.64 ± 0.34%, radionuclide purity of 99.69 ± 0.20%, specific activity and radioactive concentration at the end of irradiation (EOI) of 2.26 – 5.31 Ci/mg and 3.84 – 9.03 mCi/mL, respectively. 161 TbCl 3 solution stable for 3 weeks at room temperature with a radiochemical purity of 98.41 ± 0.42%. 161 TbCl 3 solution from irradiated natural gadolinium oxide target has the physico-chemical characteristic that meets the requirements for use as a precursor in preparation of radiopharmaceuticals. (author)

  8. The study of irradiation combined with targeted suicide gene therapy for prostate cancer xenografts

    International Nuclear Information System (INIS)

    Lu Xueguan; Milas, L.

    2007-01-01

    Objective: To study whether RGD-4C AAVP HSV-TK/GCV, one of suicide gene therapy targeting to Integrin αv, can enhance radiotherapeutic effect for DU145 prostate cancer xenografts or not. Methods: When the diameter of tumor in 48 nude mice bearing DU145 prostate cancer in the right leg attained 6.0 mm (5.8-6.3 mm), the mice were entered into the experiment. There were 6 experimental groups (8 mice per group), including the control, radiotherapy only (RT), RGD-4C AAVP HSV-TK/GCV only (Targeted, RGD-4C), AAVP HSV-TK/GCV (Non-targeted, non RGD-4C ), radiotherapy plus RGD- 4C AAVP HSV-TK/GCV(XRT + RGD-4C) and radiotherapy plus AAVP HSV-TK/GCV group (XRT + Non RGD-4C). The effect of treatment was assessed by tumor growth delay ( the time required when tumor grew from 6.0 mm to 12.0 mm) and tumor cure. Results: Five mice died during the treatment course. There were 6 mice without tumor after treatment, including 1 in RT group, 1 in RGD-4C group, 1 in non RGD-4C group and 3 in XRT + RGD-4C group, respectively. For tumor growth delay analysis in 37 mice, the absolute growth delay (AGD) for RGD-4C, non RGD-4C and RT group was 24.4 ± 9.0, 22.6±11.3 and 28.3 ±5.5 days, respectively. When RGD-4C AAVP HSV-TK/GCV or AAVP HSV-TK/GCV combined with radiotherapy, their AGD was 64.7±23.8 and 35.4±9.6 days, and nominal growth delay (NGD) was 40.3 ± 23.8 and 12.8 ± 9.6 days, respectively. The enhancement factor of RGD-4C AAVP HSV-TK/GCV and AAVP HSV-TK/GCV for radiotherapy were 1.42 and 0.45. Conclusion: RGD-4C AAVP HSV-TK/GCV can enhance radiotherapeutic effect for DU145 prostate cancer xenografts. Further study is needed. (authors)

  9. Secondary radiation yield from a surface of heavy targets, irradiated by protons of average energies (E sub p approx 1 GeV)

    CERN Document Server

    Krupnyj, G I; Yanovich, A A

    2001-01-01

    Experimental data on the nuclear reaction rates of threshold rhodium, indium, phosphorus, sulfur, aluminium, carbon, niobium and bismuth activated detectors are presented. The detectors were set up on the cylindrical surface of full absorption targets: tungsten, uranium and chloride with the molar ratios of the 70 % NaCl and 30 % PbCl sub 2 salts. The targets were irradiated by protons with the energies from 0.8 to 1.21 GeV. Growth of the reaction rate with increasing reaction of primary protons and raising atomic number of the targets, presence of the target profile, where the maximum reaction rate is observed, are noted

  10. Calculations with the quasirelativistic local-spin-density-functional theory for high-Z atoms

    International Nuclear Information System (INIS)

    Guo, Y.; Whitehead, M.A.

    1988-01-01

    The generalized-exchange local-spin-density-functional theory (LSD-GX) with relativistic corrections of the mass velocity and Darwin terms has been used to calculate statistical total energies for the neutral atoms, the positive ions, and the negative ions for high-Z elements. The effect of the correlation and relaxation correction on the statistical total energy is discussed. Comparing the calculated results for the ionization potentials and electron affinities for the atoms (atomic number Z from 37 to 56 and 72 to 80) with experiment, shows that for the atoms rubidium to barium both the LSD-GX and the quasirelativistic LSD-GX, with self-interaction correction, Gopinathan, Whitehead, and Bogdanovic's Fermi-hole parameters [Phys. Rev. A 14, 1 (1976)], and Vosko, Wilk, and Nusair's correlation correction [Can. J. Phys. 58, 1200 (1980)], are very good methods for calculating ionization potentials and electron affinities. For the atoms hafnium to mercury the relativistic effect has to be considered

  11. In situ measurement of low-Z material coating thickness on high Z substrate for tokamaks

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, D., E-mail: dmueller@pppl.gov; Roquemore, A. L.; Jaworski, M.; Skinner, C. H.; Miller, J.; Creely, A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Raman, P.; Ruzic, D. [Department of Nuclear, Plasma, and Radiological Engineering, Center for Plasma Material Interaction, University of Illinois, Urbana, Illinois 61801 (United States)

    2014-11-15

    Rutherford backscattering of energetic particles can be used to determine the thickness of a coating of a low-Z material over a heavier substrate. Simulations indicate that 5 MeV alpha particles from an {sup 241}Am source can be used to measure the thickness of a Li coating on Mo tiles between 0.5 and 15 μm thick. Using a 0.1 mCi source, a thickness measurement can be accomplished in 2 h of counting. This technique could be used to measure any thin, low-Z material coating (up to 1 mg/cm{sup 2} thick) on a high-Z substrate, such as Be on W, B on Mo, or Li on Mo. By inserting a source and detector on a moveable probe, this technique could be used to provide an in situ measurement of the thickness of Li coating on NSTX-U Mo tiles. A test stand with an alpha source and an annular solid-state detector was used to investigate the measurable range of low-Z material thicknesses on Mo tiles.

  12. Improvement on the light yield of a high-Z inorganic scintillator GSO(Ce)

    CERN Document Server

    Kamae, T; Isobe, N; Kokubun, M; Kubota, A; Osone, S; Takahashi, T; Tsuchida, N; Ishibashi, H

    2002-01-01

    Cerium-doped gadolinium silicic dioxide crystal, GSO(Ce), is a high-Z non-hydroscopic scintillator that gives higher light yield than BGO, and can potentially replace NaI(Tl), CsI(Tl) and BGO in many applications. Its production cost, however, has been substantially higher than any of them, while its energy resolution has been worse than that of NaI(Tl) or CsI(Tl). The merit did not overcome these deficiencies except in limited applications. We developed a low background phoswich counter (the well-type phoswich counter) for the Hard X-ray Detector of the Astro-E project based on GSO scintillator. In the developmental work, we have succeeded in improving the light yield of GSO(Ce) by 40-50%. For energies above 500 keV, a large GSO(Ce) crystal (4.5 cmx4.5phi cm) now gives energy resolution comparable to or better than the best NaI(Tl) when read out with a phototube. With a small GSO(Ce) crystal (5x5x5 mm sup 3) and a photodiode, an energy resolution comparable to or better than the best CsI(Tl) has been obtaine...

  13. Smoothing and instability with magnetic field in a non-uniformly laser-irradiated planar target

    International Nuclear Information System (INIS)

    Bell, A.R.; Epperlein, E.M.

    1986-01-01

    Calculations are presented of the magneto-hydrodynamic response of a planar target to non-uniformities in energy deposition by a laser. The amplitude of the non-uniformities are assumed small and the equations are linearised in small perturbations about the solution for steady planar ablation driven by uniform laser energy deposition. The grad(n)xgrad(T) magnetic field source is included, along with Nernst convection and the Righi-Leduc heat flow. The magnetic field is shown to give a small increase in smoothing. A source term for magnetic field is included to simulate the effects of the Weibel instability. The instability is not strong enough to overcome the smoothing processes under the present assumptions. (author)

  14. Detailed computer simulation of damage accumulation in ion irradiated crystalline targets

    International Nuclear Information System (INIS)

    Jaraiz, M.; Arias, J.; Bailon, L.A.; Barbolla, J.J.

    1993-01-01

    A new version for the collision cascade simulation program MARLOWE is presented. This version incorporates damage build-up in full detail, i.e every interstitial and vacancy generated is retained throughout the simulation and can become a target in subsequent collisions, unless they recombine at some stage during the implantation. Vacancy-interstitial recombination is simulated by annihilating those pairs whose radius is less than a specified recombination radius. Also, stopped atoms are moved to their nearest lattice interstitial site if it is not occupied. In this way, a fully physical simulation can be carried out in detail, thus preserving a valuable feature of MARLOWE. To overcome the prohibitive computation time and memory required, a scheme has been followed to handle in a suitable way the data generated as the simulation proceeds. The model is described. Examples of memory and computation time requirements and damage accumulation effects on channelling in ion implantation are also presented. (Author)

  15. Pulmonary tumors induced in the rat by the internal α irradiation; target cells and sensitive cells

    International Nuclear Information System (INIS)

    Fritsch, P.; Masse, R.; Nolibe, D.; Metivier, H.; Morin, M.; Lafuma, J.

    1977-01-01

    Over, 500 rat pulmonary tumors induced by inhalation of various radionuclides have been examined by means of the usual histological methods and ultrastructurally for part of them. Tumor grafts were obtained and several lines have been preserved for several years. The malignity of some varieties: circumscribed epidermoid carcinoma, fibrosarcoma derived from stromareaction, bronchiolo alveolar carcinoma was thus established. It was not possible to establish any relation between the turnover per day and the incidence of pulmonary tumors whatever the correction factor applied taking account of the distribution of the delivered dose. The possibility of showing unapparent lesions of the target cells by grafts of immunodepressed animals suggested that local regulating mechanisms are of particular significance [fr

  16. Corrosion of target and structural materials in water irradiated by an 800 MeV proton beam

    International Nuclear Information System (INIS)

    Butt, D.P.; Kanner, G.S.; Lillard, R.S.

    1996-01-01

    Radiation enhanced, aqueous corrosion of solid neutron-targets such as tungsten or tantalum, or target cladding or structural materials such as superalloys and stainless steels, is a significant concern in accelerator-driven transmutation technologies. In this paper we briefly describe our current methods for control and in situ monitoring of corrosion in accelerator cooling water loops. Using floating, electrochemical impedance spectroscopy (EIS), we have measured the corrosion rates of aluminum 6061, copper, Inconel 718, and 304L stainless steel in the flow loop of a water target irradiated by a μamp, 800 MeV proton beam. Impedance spectroscopy allows us to model the corrosion process of a material as an equivalent electrical circuit. Thus the polarization resistance, which is inversely proportional to the corrosion rate, can be extracted from the frequency response of a metal specimen. During a three month period, without the use of corrosion mitigation techniques, we observed increases of several orders of magnitude in the water conductivity and the corrosion rates. The increase in corrosion is at least partially attributed to a build up of peroxide in our pseudo-closed loop system. In this paper we also briefly describe our second generation experiments, scheduled to begin in late 1996. In these experiments we plan to measure the corrosion rates of tungsten, tantalum, Inconel 718, 316L and 304L stainless steel, HT-9 austenitic stainless steel, and aluminum 5053. Two or three electrode probes of each material are being placed directly in the proton beam, in a high neutron flux region, or a significant distance from the high radiation area. We will be measuring corrosion rates, changes in pH and conductivity, and we will be establishing parameters for filtration and mitigation of corrosion. We will also discuss our ideas for making in situ measurements of water radiolysis using optical and laser diagnostic techniques

  17. Synthesis of the studies on fuels and transmutation targets (fabrication, design, irradiation damage and dissolution) realized in the framework of the Bataille law

    International Nuclear Information System (INIS)

    Pillon, S.

    2004-12-01

    This document presents the different studied fuels and targets for the transmutation of the minor actinides and of the long life fission products for PWR/EPR and Fast neutron Reactor/EFR of today technology; the results of studies on the behavior under ions irradiation and in experimental nuclear reactor; the knowledge in terms of design, simulation and sizing; the development in terms of fabrication; the knowledge on the dissolution aptitude of these fuels and targets. (A.L.B.)

  18. Experimental and theoretical study of the yields of residual product nuclei produced in thin targets irradiated by 100-2600 MeV protons

    CERN Document Server

    Titarenko, Y E; Karpikhin, E I

    2003-01-01

    The objective of the project is measurements and computer simulations of independent and cumulative yields of residual product nuclei in thin targets relevant as target materials and structure materials for hybrid accelerator-driven systems coupled to high-energy proton accelerators. The yields of residual product nuclei are of great importance when estimating such basic radiation-technology characteristics of hybrid facility targets as the total target activity, target 'poisoning', buildup of long-lived nuclides that, in turn, are to be transmuted, product nuclide (Po) alpha-activity, content of low-pressure evaporated nuclides (Hg), content of chemically-active nuclides that spoil drastically the corrosion resistance of the facility structure materials, etc. In view of the above, radioactive product nuclide yields from targets and structure materials were determined by an experiment using the ITEP U-10 proton accelerator in 51 irradiation runs for different thin targets: sup 1 sup 8 sup 2 sup , sup 1 sup 8 ...

  19. Characterization of microRNAs and their target genes associated with transcriptomic changes in gamma-irradiated Arabidopsis.

    Science.gov (United States)

    Kim, J H; Go, Y S; Kim, J K; Chung, B Y

    2016-07-29

    MicroRNAs (miRNAs) regulate gene expression in response to biotic and abiotic stress in plants. We investigated gamma-ray-responsive miRNAs in Arabidopsis wild-type and cmt3-11t mutant plants using miRNA microarray analysis. miRNA expression was differentiated between the wild-type and cmt3-11t mutants. miR164a, miR169d, miR169h, miR172b*, and miR403 were identified as repressible in the wild-type and/or cmt3-11t mutant in response to gamma irradiation, while miR827, miR840, and miR850 were strongly inducible. These eight miRNA genes contain UV-B-responsive cis-elements, including G-box, I-box core, ARE, and/or MBS in the putative promoter regions. Moreover, Box 4, MBS, TCA-element, and Unnamed_4, as well as CAAT- and TATA-box, were identified in these eight miRNA genes. However, a positive correlation between the transcriptions of miRNAs and their putative target genes was only observed between miR169d and At1g30560 in the wild-type, and between miR827 and At1g70700 in the cmt3-11t mutant. Quantitative RT-PCR analysis confirmed that the transcription of miR164a, miR169d, miR169h, miR172b*, miR403, and miR827 differed after gamma irradiation depending on the genotype (wild-type, cmt3-11t, drm2, drd1-6, and ddm1-2) and developmental stage (14 or 28 days after sowing). In contrast, high transcriptional induction of miR840 and miR850 was observed in these six genotypes regardless of the developmental stage. Although the actual target genes and functions of miR840 and miR850 remain to be determined, our results indicate that these two miRNAs may be strongly induced and reproducible genetic markers in Arabidopsis plants exposed to gamma rays.

  20. Effects of low-Z and high-Z impurities on divertor detachment and plasma confinement

    Directory of Open Access Journals (Sweden)

    H.Q. Wang

    2017-08-01

    Full Text Available The impurity-seeded detached divertor is essential for heat exhaust in ITER and other reactor-relevant devices. Dedicated experiments with injection of N2, Ne and Ar have been performed in DIII-D to assess the impact of the different impurities on divertor detachment and confinement. Seeding with N2, Ne and Ar all promote divertor detachment, greatly reducing heat flux near the strike point. The upstream plasma density at the onset of detachment decreases with increasing impurity-puffing flow rates. For all injected impurity species, the confinement and pedestal pressure are correlated with the impurity content and the ratio of separatrix loss power to the l-H transition threshold power. As the divertor plasma approaches detachment, the high-Z impurity seeding tends to degrade the core confinement owing to the increased core radiation. In particular, Ar injection with up to 50% of the injected power radiating in the core cools the pedestal and core plasmas, thus significantly degrading the confinement. As for Ne seeding, medium confinement with H98∼0.8 can be maintained during the detachment phase with the pedestal temperature being reduced by about 50%. In contrast, in the N2 seeded plasmas, radiation is predominately confined in the boundary plasma, which leads to less effect on the confinement and pedestal. In the case of strong N2 gas puffing, the confinement recovers during the detachment, from ∼20% reduction at the onset of the detachment to greater than unity comparable to that before the seeding. The core and pedestal temperatures feature a reduction of 30% from the initial attached phase and remain nearly constant during the detachment phase. The improvement in confinement appears to arise from the increase in pedestal and core density despite the temperature reduction.

  1. EUV Spectra of High Z Impurities from Large Helical Device and Atomic Data

    International Nuclear Information System (INIS)

    Kato, T.; Suzuki, C.; Funaba, H.; Sato, K.; Murakami, I.; Kato, D.; Sakaue, H.; O’Sullivan, G.; Harte, C.; White, J.; D’Arcy, R.; Tanuma, H.; Nakamura, N.

    2017-01-01

    The results of experiments on high Z impurity injection in the Large Helical Device at the National Institute for Fusion Science are described. Spectra from Xe, Sn and W ions were recorded in the extreme ultraviolet spectral region. Two different situations were observed in the case of Xe and Sn, depending on whether or not the plasma underwent radiative collapse. If the plasma was stable, the spectrum consisted of a number of strong lines and in both cases the strongest contribution was from 4p - 4d transitions of Cu-like ions. If the plasma underwent radiative collapse in each case it was dominated by an intense unresolved transition array with some strong lines overlapping it resulting from 4p 6 4d m - 4p 5 4d m+1 + 4p 6 4d m-1 4f transitions. For tungsten, radiative collapse was not observed though the spectrum here was dominated by the same array which lies between 4.5 and 7 nm with some additional contribution at the same wavelength from 4d 10 4f m - 4d 9 4f m+1 and 4d 10 4f m - 4d 10 4f m-1 5d transitions in lower stages also. From observation and comparison with other sources, it is shown that the spectra are dominated by resonance transitions to the ground state of the emitting ions, in marked contrast to results from charge exchange spectra that had been recorded to assist with ion stage separation. In the case of tungsten, no sharp lines are seen though the profile of the unresolved array structure changes with plasma temperature and the origin of these changes can be traced to differences in the populations of contributing ions. New assignments for lines of Xe XVIII, Sn XIX and Sn XVII of 4p - 4d transitions are listed in Tables. Strong lines of W, Xe and Sn ions in EUV range are also tabulated. (author)

  2. Metal enrichment signatures of the first stars on high-z DLAs

    Science.gov (United States)

    Ma, Q.; Maio, U.; Ciardi, B.; Salvaterra, R.

    2017-12-01

    We use numerical N-body hydrodynamical simulations with varying PopIII stellar models to investigate the possibility of detecting first star signatures with observations of high-redshift damped Lyα absorbers (DLAs). The simulations include atomic and molecular cooling, star formation, energy feedback and metal spreading due to the evolution of stars with a range of masses and metallicities. Different initial mass functions (IMFs) and corresponding metal-dependent yields and lifetimes are adopted to model primordial stellar populations. The DLAs in the simulations are selected according to either the local gas temperature (temperature selected) or the host mass (mass selected). We find that 3 per cent (40 per cent) of mass (temperature)-selected high-z (z ≥ 5.5) DLAs retain signatures of pollution from PopIII stars, independent of the first star model. Such DLAs have low halo mass ( Z⊙) and star formation rate ( generation and to constrain the first star mass ranges. Comparing the abundance ratios derived from our simulations to those observed in DLAs at z ≥ 5, we find that most of these DLAs are consistent within errors with PopII star dominated enrichment and strongly disfavour the pollution pattern of very massive first stars (i.e. 100-500 M⊙). However, some of them could still result from the pollution of first stars in the mass range [0.1, 100] M⊙. In particular, we find that the abundance ratios from SDSS J1202+3235 are consistent with those expected from PopIII enrichment dominated by massive (but not extreme) first stars.

  3. UV-C irradiation of HSV-1 infected fibroblasts (HSV-FS) enhances human natural killer (NK) cell activity against these targets

    International Nuclear Information System (INIS)

    Pettera, L.; Fitzgerald-Bocarsly, P.

    1991-01-01

    Expression of Herpes Simplex Virus Type 1 (HSV-1) immediate early gene products has been bound to be sufficient for NK cell mediated lysis of HSV-1 infected FS. To block the targets at various stages in the infectious cycle, HSV-FS were irradiated with UV light for 1 min at 2, 6, and 20 hr post-infection. NK mediated lysis of 2 hr and 5 hr UV treated HSV-FS was 2-fold higher than non-UV treated HSV-FS despite a >99% inhibition in virus yield. In contrast, 20 hr infected targets were lysed less well than 2 and 6 hr targets despite strong glycoprotein expression and induction of high levels of interferon-alpha (IFN-α) production by effector PBMC's; this lysis was not enhanced by UV treatment. Since NK lysis of HSV-FS has been found to be dependent on an HLA-DR + accessory cell (AC), lysis of irradiated HSV-FS by PBMC's depleted of AC was measured. Such depletion eradicated NK lysis of the UV treated HSV-FS indicating that irradiation does not overcome the AC requirement for NK lysis. UV irradiation of another HLA-DR + dependent target, Vesicular Stomatitis Virus (VSV) infected FS led to a dramatic reduction in both NK lysis and IFN-α induction. HSV-1 is a DNA virus whose genes are expressed in a cascade fashion whereas VSV is an RNA virus. The authors hypothesize that the enhancement in AC dependent NK activity observed for UV irradiated HSV-FS, but not VSV-FS, targets is due to overproduction of either a cellular or viral gene product which specifically occurs early in the HSV-1 infectious cycle and is downregulated by 20 hr post-infection

  4. Neutronic and thermal-hydraulic analysis of a device for irradiation of LEU UAlx-Al targets for 99Mo production in the IEA-R1 reactor

    International Nuclear Information System (INIS)

    Nishiyama, Pedro Julio Batista de Oliveira

    2012-01-01

    Technetium-99m ( 99m Tc), the product of radioactive decay of molybdenum-99 ( Mo), is one of the most widely used radioisotope in nuclear medicine, covering approximately 80% of all radiodiagnosis procedures in the world. Nowadays, Brazil requires an amount of about 450 Ci of 99 Mo per week. Due to the crisis and the shortage of 99 Mo supply chain that has been observed on the world since 2008, IPEN/CNEN-SP decided to develop a project to produce 99 Mo through fission of uranium-235. The objective of this dissertation was the development of neutronic and thermal-hydraulic calculations to evaluate the operational safety of a device for 99 Mo production to be irradiated in the IEA-Rl reactor core at 5 MW. In this device will be placed ten targets of UAl x -Al dispersion fuel with low enriched uranium (LEU) and density of 2.889 gU/cm 3 . For the neutronic calculations were utilized the computer codes HAMMER-TECHNION and CITATION and the maximum temperatures reached in the targets were calculated with the code MTRCR-IEA-R1. The analysis demonstrated that the device irradiation will occur without adverse consequences to the operation of the reactor. The total amount of 99 Mo was calculated with the program SCALE and considering that the time needed for the chemical processing and recovering of the 99 Mo will be five days after the irradiation, we have that the 99 Mo activity available for distribution will be 176 Ci for 3 days of irradiation, 236 Ci for 5 days of irradiation and 272 Ci for 7 days of targets irradiation. (author)'

  5. Spatial distribution of neutrons in paraffin moderator surrounding a lead target irradiated with protons at intermediate energies

    International Nuclear Information System (INIS)

    Adam, J.; Barabanov, M.Yu.; Bradnova, V.

    2002-01-01

    The distribution of neutrons emitted during the irradiation with 0.65, 1.0 and 1.5 GeV protons from a lead target (O / = 8 cm, l = 20 cm) and moderated by a surrounding paraffin moderator of 6 cm thick was studied with a radiochemical sensor along the beam axis on top of the moderator. Small 139 La-sensors of approximately 1 g were used to measure essentially the thermal neutron fluence at different depths near the surface: i.e., on top of the moderator, in 10 mm deep holes and in 20 mm deep holes. The reaction 139 La(n, γ) 140 La (τ 1/2 = 40.27 h) was studied using standard procedures of gamma spectroscopy and data analysis. The neutron induced activity of 140 La increases strongly with the depth of the hole inside the moderator, its activity distribution along the beam direction on top of the moderator has its maximum about 10 cm downstream the entrance of the protons into the lead and the induced activity increases about linearity with the proton energy. Some comparisons of the experimental results with model estimations based on the LAHET code are also presented. The experiments were carried out using the Nuclotron accelerator of the Laboratory of High Energies (JINR)

  6. Spatial distribution of neutrons in paraffin moderator surrounding a lead target irradiated with protons at intermediate energies

    CERN Document Server

    Adam, J; Bradnova, V

    2002-01-01

    The distribution of neutrons emitted during the irradiation with 0.65, 1.0 and 1.5 GeV protons from a lead target (O / = 8 cm, l = 20 cm) and moderated by a surrounding paraffin moderator of 6 cm thick was studied with a radiochemical sensor along the beam axis on top of the moderator. Small sup 1 sup 3 sup 9 La-sensors of approximately 1 g were used to measure essentially the thermal neutron fluence at different depths near the surface: i.e., on top of the moderator, in 10 mm deep holes and in 20 mm deep holes. The reaction sup 1 sup 3 sup 9 La(n, gamma) sup 1 sup 4 sup 0 La (tau sub 1 sub / sub 2 = 40.27 h) was studied using standard procedures of gamma spectroscopy and data analysis. The neutron induced activity of sup 1 sup 4 sup 0 La increases strongly with the depth of the hole inside the moderator, its activity distribution along the beam direction on top of the moderator has its maximum about 10 cm downstream the entrance of the protons into the lead and the induced activity increases about linearity ...

  7. Comparison on the production of radionuclides in 1.4 GeV proton irradiated LBE targets of different thickness

    CERN Document Server

    Maiti, Moumita; Mendonça, Tania M; Stora, Thierry; Lahiri, Susanta

    2014-01-01

    This is the first report on the inventory of radionuclides produced in 1.4 GeV proton induced reaction on Lead-Bismuth Eutectic (LBE) targets. LBE targets of 6 mm diameter and 1 to 8 mm lengths were irradiated with 1.4 GeV protons. The radionuclides ranging from Be-7 (53.12 days) to Po-207 (5.8 h) were identified in the samples with the help of time resolved gamma-ray spectroscopy. However, there is no signature of formation of At radioisotopes, which can be produced by the interaction of secondary particles, typical for thick targets.

  8. Development of lithium target system in engineering validation and engineering design activity of the international fusion materials irradiation facility (IFMIF/EVEDA)

    International Nuclear Information System (INIS)

    Wakai, Eiichi; Kondo, Hiroo; Sugimoto, Masayoshi; Ida, Mizuho; Kanemura, Takuji; Watanabe, Kazuyoshi; Fujishiro, Kouji; Edao, Yuuki; Niitsuma, Shigeto; Kimura, Haruyuki; Fukada, Satoshi; Hiromoto, Tetsushi; Shigeharu, Satoshi; Yagi, Jyuro; Furukawa, Tomohiro; Hirakawa, Yasushi; Suzuki, Akihiro; Terai, Takayuki; Horiike, Hiroshi; Hoashi, Eiji; Suzuki, Sachiko; Yamaoka, Nobuo; Serizawa, Hisashi; Kawahito, Yosuke; Tsuji, Yoshiyuki; Furuya, Kazuyuki; Takeo, Fumio

    2012-01-01

    Engineering validation and engineering design activity (EVEDA) for the international fusion materials irradiation facility (IFMIF) has been conducted since 2007. Research and development of the Lithium target facility is an important part of this activity. We constructed a world largest liquid Lithium test loop with a capacity of 5000 L in 2010 and successfully completed the first stage validation tests (functional tests of components and Lithium flow test (flow velocity 15 m/s at the target). In the present article, recent results of the EVEDA activity for the Lithium target facility and related technologies on liquid Lithium are reviewed. (author)

  9. Analytical models for development of high performance metal targets irradiated in IPEN-CNEN/SP Cyclone 30 and Cyclone 18 cyclotrons

    International Nuclear Information System (INIS)

    Oliveira, Henrique Barcellos de

    2009-01-01

    Analytical models were developed that describe the basic elements for metal targets irradiation in cyclotrons. Important parameters such as maximum beam current value and thermal power deposited on target were obtained and compared with practical situations. In an unprecedented way, were determined analytically the features found in intense thermal transient situations, when high protons concentrations in a small region of the beam cause intense temperature gradients in small regions of the target. Comparing with results found in the literature showed that the developed models are satisfactory, in view of all limitations of the proposed model. (author)

  10. Yet another UFO in the X-ray spectrum of a high-z lensed QSO

    Science.gov (United States)

    Dadina, M.; Vignali, C.; Cappi, M.; Lanzuisi, G.; Ponti, G.; Torresi, E.; De Marco, B.; Chartas, G.; Giustini, M.

    2018-02-01

    Aim. Ultra-fast outflows (UFO) appear to be common in local active galactic nuclei (AGN) and may be powerful enough (Ėkin ≥ 1% of Lbol) to effectively quench the star formation in their host galaxies. To test feedback models based on AGN outflows, it is mandatory to investigate UFOs near the peak of AGN activity, that is, at high-z where only a few studies are available to date. Methods: UFOs produce Fe resonant absorption lines measured above ≈7 keV. The most critical problem in detecting such features in distant objects is the difficulty in obtaining X-ray data with sufficient signal-to-noise. We therefore selected a distant QSO that gravitational lensing made bright enough for these purposes, the z = 2.64 QSO MG J0414+0534, and observed it with XMM-Newton for ≈78 ks. Results: The X-ray spectrum of MG J0414+0534 is complex and shows signatures of cold absorption (NH ≈ 4 × 1022 cm-2) and of the presence of an iron emission line (E ≈ 6.4 keV, EW = 95 ± 53 eV) consistent with it originating in the cold absorber. Our main result, however, is the robust detection (more than 5σ) of an absorption line at Eint ≈ 9.2 keV (Eobs ≈ 2.5 keV observer frame). If interpreted as due to FeXXVI, it implies gas outflowing at vout ≈ 0.3c. To our knowledge, this is the first detection of an UFO in a radio-loud quasar at z ≥ 1.5. We estimated that the UFO mechanical output is Ėkin ≈ 2.5Lbol with ṗout/ṗrad ≈ 17 indicating that it is capable of installing significant feedback between the super-massive black hole and the bulge of the host galaxy. We argue that this also suggests a magnetic driving origin of the UFO.

  11. Spotting high-z molecular absorbers using neutral carbon. Results from a complete spectroscopic survey with the VLT

    Science.gov (United States)

    Noterdaeme, P.; Ledoux, C.; Zou, S.; Petitjean, P.; Srianand, R.; Balashev, S.; López, S.

    2018-04-01

    While molecular quasar absorption systems provide unique probes of the physical and chemical properties of the gas as well as original constraints on fundamental physics and cosmology, their detection remains challenging. Here we present the results from a complete survey for molecular gas in thirty-nine absorption systems selected solely upon the detection of neutral carbon lines in Sloan Digital Sky Survey (SDSS) spectra, without any prior knowledge of the atomic or molecular gas content. H2 is found in all twelve systems (including seven new detections) where the corresponding lines are covered by the instrument setups and measured to have logN(H2) ≳ 18, indicating a self-shielded regime. We also report seven CO detections (7/39) down to logN(CO) 13.5, including a new one, and put stringent constraints on N(CO) for the remaining 32 systems. N(CO) and N(C I) are found to be strongly correlated with N(CO)/N(C I) 1/10. This suggests that the C I-selected absorber population is probing gas deeper than the H I–H2 transition in which a substantial fraction of the total hydrogen in the cloud is in the form of H2. We conclude that targeting C I-bearing absorbers is a very efficient way to find high-metallicity molecular absorbers. However, probing the molecular content in lower-metallicity regimes as well as high-column-density neutral gas remains to be undertaken to unravel the processes of gas conversion in normal high-z galaxies. Based on observations and archival data from the European Southern Observatory (ESO) prog. IDs 060.A-9024, 072.A-0346, 278.A-5062, 080.A-0482, 080.A-0795, 081.A-0242, 081.A-0334, 082.A-0544, 082.A-0569, 083.A-0454, 084.A-0699, 086.A-0074 and 086.A-0643 using the Ultraviolet and Visual Echelle Spectrograph (UVES) and X-shooter at the Very Large Telescope (VLT), on Cerro Paranal, Chile.

  12. Membrane-Dependent Bystander Effect Contributes to Amplification of the Response to Alpha-Particle Irradiation in Targeted and Nontargeted Cells

    International Nuclear Information System (INIS)

    Hanot, Maite; Hoarau, Jim; Carriere, Marie; Angulo, Jaime F.; Khodja, Hicham

    2009-01-01

    Purpose: Free radicals are believed to play an active role in the bystander response. This study investigated their origin as well as their temporal and spatial impacts in the bystander effect. Methods and Materials: We employed a precise alpha-particle microbeam to target a small fraction of subconfluent osteoblastic cells (MC3T3-E1). γH2AX-53BP1 foci, oxidative metabolism changes, and micronuclei induction in targeted and bystander cells were assessed. Results: Cellular membranes and mitochondria were identified as two distinct reactive oxygen species producers. The global oxidative stress observed after irradiation was significantly attenuated after cells were treated with filipin, evidence for the primal role of membrane in the bystander effect. To determine the membrane's impact at a cellular level, micronuclei yield was measured when various fractions of the cell population were individually targeted while the dose per cell remained constant. Induction of micronuclei increased in bystander cells as well as in targeted cells and was attenuated by filipin treatment, demonstrating a role for bystander signals between irradiated cells in an autocrine/paracrine manner. Conclusions: A complex interaction of direct irradiation and bystander signals leads to a membrane-dependent amplification of cell responses that could influence therapeutic outcomes in tissues exposed to low doses or to environmental exposure.

  13. On the possibility of using lithium-6 deuteride, irradiated with gas discharge plasma in a target with polarized nuclei of deuterium and lithium

    International Nuclear Information System (INIS)

    Bunyatova, E.I.; Bubnov, N.N.; Solodovnikov, S.P.

    1991-01-01

    A target with polarized nuclei made on the basis of irradiated lithium-6 deuteride is of great interest for carrying out investigations in elementary particle physics. Up to now high-energy electrons have been used for generation of F-centers in 6 LiD. It is shown that one can, in principle, use ultraviolet irradiation and gas discharge plasma for generation of F-centers in 6 LiD. Both types of irradiation cause electron paramagnetic resonance signals from conductance electrons of lithium and form F-centers in 6 LiD. It seems possible to obtain the necessary samples by exposing 6 LiD to the gas discharge plasma. 9 refs.; 2 figs

  14. Monte Carlo modelling and comparison with experiment of the nuclide production in thick stony targets isotropically irradiated with 600 MeV protons

    International Nuclear Information System (INIS)

    Aylmer, D.; Herzog, G.F.; Kruse, T.H.; Cloth, P.; Filges, D.; Moniot, R.K.; Signer, P.; Wieler, R.; Tuniz, C.

    1987-05-01

    Depth profiles for the production of stable and radioactive nuclides have been measured for a large variety of target elements in three thick spherical stony targets with radii of 5, 15 and 26 cm isotropically irradiated with 600 MeV protons at the CERN synchrocyclotron. These irradiation experiments (CERN SC96) were intended to simulate the irradiation of meteoroids by galactic cosmic ray protons. In order to combine this experimental approach with a theoretical one the intra- and internuclear cascades were calculated using Monte Carlo techniques via the high energy transport code HET/KFA 1. Together with transport calculations for low energy neutrons by the MORSE-CG code the depth dependent spectra of primary and secondary protons and of secondary neutrons were derived. On the basis of these spectra and a set of evaluated experimental excitation functions for p-induced reactions and of theoretical ones for n-induced reactions, calculated by the code ALICE LIVERMORE 82, theoretical depth profiles for the production of stable and radioactive nuclides in the three thick targets were calculated. This report is a comprehensive survey on all those target/product combination for which both experimental and theoretical data are available. It provides the basis for a detailed discussion of the various production modes of residual nuclides and on the depth and size dependence of their production rates in thick stony targets, serving as a simulation of the galactic cosmic ray irradiation of meteoroids in space. On the other hand the comparison of the experimental and theoretical depth profiles validates the high energy transport calculations, making them a promissing tool for further model calculations of the interactions of cosmic rays with matter. (orig.)

  15. Decreased repopulation as well as increased reoxygenation contribute to the improvement in local control after targeting of the EGFR by C225 during fractionated irradiation

    International Nuclear Information System (INIS)

    Krause, Mechthild; Ostermann, Gernot; Petersen, Cordula; Yaromina, Ala; Hessel, Franziska; Harstrick, Andreas; Kogel, Albert J van der; Thames, Howard D; Baumann, Michael

    2005-01-01

    Background and purpose: Inhibition of repopulation and enhanced reoxygenation has been suggested to contribute to improvement of local tumour control after fractionated irradiation combined with inhibitors of the epidermal growth factor receptor (EGFR). The present study addresses this hypothesis in FaDu human squamous cell carcinoma. For this tumour model marked repopulation and incomplete reoxygenation during fractionated irradiation has previously been demonstrated. Furthermore, the anti-EGFR monoclonal antibody C225 has been shown to significantly improve the results of fractionated irradiation in this tumour. Materials and methods: FaDu tumours in nude mice were irradiated with 18 fractions in 18 days (18f/18d) or 18 fractions in 36 days (18f/36d). Three Gy fractions were given either under ambient or under clamp hypoxic conditions. C225 or carrier was applied four times during the course of treatment. Fractionated irradiations were followed by graded top-up doses to obtain complete dose-response curves for local tumour control. Tumour control dose 50% (TCD 50 ) was determined at day 120 after end of treatment. Results: Significant repopulation and reoxygenation occurred during fractionated irradiation of FaDu tumours (P-values between 0.028 and 50 for 18f/36d under ambient conditions (P=0.04). Bootstrap analysis revealed decreased repopulation and increased reoxygenation after application of C225 (P=0.06 for the combined effect). This was further corroborated by a significant effect of C225 on the 'repopulated' dose under ambient conditions which is influenced by both, reoxygenation and repopulation (P=0.012). Conclusions: Our study provides evidence that both decreased repopulation as well as increased reoxygenation contribute to the improvement of local control after targeting of EGFR by C225 during fractionated irradiation of FaDu tumours

  16. Load and unload system optimization on H218 O irradiation target used for 18F- production at the cyclotron cyclone 30 from IPEN-CNEN/SP, Brazil

    International Nuclear Information System (INIS)

    Costa, Osvaldo Luiz da

    2009-01-01

    The demand growing in Brazil by the radiopharmaceutical [ 18 F] FDG in positron emission tomography (PET-CT) and the 109,7 minutes half life claim special attention to the productive chain of this radiopharmaceutical. Since the [ 18 O]water irradiation until the tomograph patient scanning, in sequential procedures that may spent about six hours, all the productive chain stages must be as reliable as possible, because any stage failed will be perceived in productive chain extremity. The position indication absence from Load and Unload 18 F - Target System valve in Cyclotron Accelerators Center resulted in 18 F - production loss, Irradiation Room contamination and the increase workers dose responsible by operation and maintenance of irradiation systems. This study tested the behaviour of three types of position sensors (micro switch, reed switch and inductive sensor), into Irradiation Room 1.2 environment of the Cyclotron Accelerators Center, where there are high gamma radiation and neutrons rates because the routine 18 F - and 123 I production, through this test was possible to discover the fitter position sensor to run on 18 F - Target, and after rewriting the programmable logic controller software was possible avoid this type of fail at 18 F - production time in Cyclotron Accelerators Center, and to grow up the reliability on [ 18 F]FDG productive chain. (author)

  17. Load unload system optimization on H218O irradiation target used for 18F- production at the cyclotron cyclone 30 from IPEN-CNEN/SP

    International Nuclear Information System (INIS)

    Costa, Osvaldo Luiz da

    2009-01-01

    The demand growing in Brazil by the radiopharmaceutical [ 18 F]FDG in positron emission tomography (PET-CT) and the 109,7 minutes half life claim special attention to the productive chain of this radiopharmaceutical. Since the [ 18 O]water irradiation until the tomograph patient scanning, in sequential procedures that may spent about six hours, all the productive chain stages must be as reliable as possible, because any stage failed will be perceived in productive chain extremity. The position indication absence from Load and Unload 18 F- Target System valve in Cyclotron Accelerators Center resulted in 18 F- production loss, Irradiation Room contamination and the increase workers' dose responsible by operation and maintenance of irradiation systems. This study tested the behaviour of three types of position sensors (micro switch, reed switch and inductive sensor), into Irradiation Room 1.2 environment of the Cyclotron Accelerators Center, where there are high gamma radiation and neutrons rates because the routine 18 F- and 1 '2 3 I production, through this test was possible to discover the fitter position sensor to run on 18 F- Target, and after rewriting the programmable logic controller software was possible avoid this type of fail at 18 F- production time in Cyclotron Accelerators Center, and to grow up the reliability on [ 18 F]FDG productive chain. (author)

  18. Cross-sections of residual nuclei from deuteron irradiation of thin thorium target at energy 7 GeV

    Directory of Open Access Journals (Sweden)

    Vespalec Radek

    2017-01-01

    Full Text Available The residual nuclei yields are of great importance for the estimation of basic radiation-technology characteristics (like a total target activity, production of long-lived nuclides etc. of accelerator driven systems planned for transmutation of spent nuclear fuel and for a design of radioisotopes production facilities. Experimental data are also essential for validation of nuclear codes describing various stages of a spallation reaction. Therefore, the main aim of this work is to add new experimental data in energy region of relativistic deuterons, as similar data are missing in nuclear databases. The sample made of thin natural thorium foil was irradiated at JINR Nuclotron accelerator with a deuteron beam of the total kinetic energy 7 GeV. Integral number of deuterons was determined with the use of aluminum activation detectors. Products of deuteron induced spallation reaction were qualified and quantified by means of gamma-ray spectroscopy method. Several important spectroscopic corrections were applied to obtain results of high accuracy. Experimental cumulative and independent cross-sections were determined for more than 80 isotopes including meta-stable isomers. The total uncertainty of results rarely exceeded 9%. Experimental results were compared with MCNP6.1 Monte-Carlo code predictions. Generally, experimental and calculated cross-sections are in a reasonably good agreement, with the exception of a few light isotopes in a fragmentation region, where the calculations are highly under-estimated. Measured data will be useful for future development of high-energy nuclear codes. After completion, final data will be added into the EXFOR database.

  19. 80 A/cm2 electron beams from metal targets irradiated by KrCl and XeCl excimer lasers

    Science.gov (United States)

    Beloglazov, A.; Martino, M.; Nassisi, V.

    1996-05-01

    Due to the growing demand for high-current and long-duration electron-beam devices, laser electron sources were investigated in our laboratory. Experiments on electron-beam generation and propagation from aluminium and copper targets illuminated by XeCl (308 nm) and KrCl (222 nm) excimer lasers, were carried out under plasma ignition due to laser irradiation. This plasma supplied a spontaneous accelerating electric field of about 370 kV/m without an external accelerating voltage. By applying the modified one-dimensional Poisson equation, we computed the expected current and we also estimated the plasma concentration during the accelerating process. At 40 kV of accelerating voltage, an output current pulse of about 80 A/cm2 was detected from an Al target irradiated by the shorter wavelength laser.

  20. Preliminary results on neutron production from a Pb/U target irradiated by deuteron beam at 1.25 GeV/amu

    International Nuclear Information System (INIS)

    Fragopoulou, M.; Manolopoulou, M.; Jokic, S.; Zamani, M.; Krivopustov, M.; Sosnin, A.; Stoulos, S.

    2008-01-01

    A spallation neutron source consisted of a cylindrical Pb target and surrounded by uranium blanket was irradiated by deuteron beam 1.25 GeV/amu provided from the Nuclotron accelerator at High Energy Laboratory, JINR, Dubna. For radiation protection purpose a polyethylene shielding was placed around the spallation neutron source. Neutron distributions along the surface of the U-blanket were measured by using solid state nuclear track detectors (SSNTDs) as particle and fission detectors. The neutron distributions appear to be similar to those obtained by proton irradiations. Applying a fitting procedure to the experimental data the inelastic cross section of deuteron in Pb was estimated. The escaping neutron distribution from the polyethylene shielding and parallel to the target was also measured and presented to be two orders of magnitude less than that over the U-blanket surface

  1. High-z objects and cold dark matter cosmogonies - Constraints on the primordial power spectrum on small scales

    Science.gov (United States)

    Kashlinsky, A.

    1993-01-01

    Modified cold dark matter (CDM) models were recently suggested to account for large-scale optical data, which fix the power spectrum on large scales, and the COBE results, which would then fix the bias parameter, b. We point out that all such models have deficit of small-scale power where density fluctuations are presently nonlinear, and should then lead to late epochs of collapse of scales M between 10 exp 9 - 10 exp 10 solar masses and (1-5) x 10 exp 14 solar masses. We compute the probabilities and comoving space densities of various scale objects at high redshifts according to the CDM models and compare these with observations of high-z QSOs, high-z galaxies and the protocluster-size object found recently by Uson et al. (1992) at z = 3.4. We show that the modified CDM models are inconsistent with the observational data on these objects. We thus suggest that in order to account for the high-z objects, as well as the large-scale and COBE data, one needs a power spectrum with more power on small scales than CDM models allow and an open universe.

  2. Radiochemical separations of target-like reaction products from Au-, Pt-, and Th-targets after irradiation with GeV protons

    International Nuclear Information System (INIS)

    Szweryn, B.; Bruechle, W.; Schausten, B.; Schaedel, M.

    1988-08-01

    Chemical separation procedures for separations of reaction products after spallation reactions with 2.6 GeV protons and heavy element targets are presented. To determine independent cross sections of individual isotopes the elements Au, Pt, Ir, Os, Re, W, Ta, Hf, (Lu, Yb, Tm, Er), (Gd, Eu, Sm), were separated from gold targets, Pt, Ir, Os, W, Ta, Hf, (Lu, Yb, Tm, Er), (Gd, Eu, Sm) from a platinum target and Au, Tl from a thorium target. (orig.)

  3. Temperature Effects on the Mechanical Properties of Candidate SNS Target Container Materials after Proton and Neutron Irradiation; TOPICAL

    International Nuclear Information System (INIS)

    Byun, T.S.

    2001-01-01

    This report presents the tensile properties of EC316LN austenitic stainless steel and 9Cr-2WVTa ferritic/martensitic steel after 800 MeV proton and spallation neutron irradiation to doses in the range 0.54 to 2.53 dpa. Irradiation temperatures were in the range 30 to 100 C. Tensile testing was performed at room temperature (20 C) and 164 C to study the effects of test temperature on the tensile properties. Test materials displayed significant radiation-induced hardening and loss of ductility due to irradiation. The EC316LN stainless steel maintained notable strain-hardening capability after irradiation, while the 9Cr-2WVTa ferritic/martensitic steel posted negative strain hardening. In the EC316LN stainless steel, increasing the test temperature from 20 C to 164 C decreased the strength by 13 to 18% and the ductility by 8 to 36%. The tensile data for the EC316LN stainless steel irradiated in spallation conditions were in line with the values in a database for 316 stainless steels for doses up to 1 dpa irradiated in fission reactors at temperatures below 200 C. However, extra strengthening induced by helium and hydrogen contents is evident in some specimens irradiated to above about 1 dpa. The effect of test temperature for the 9Cr-2WVTa ferritic/martensitic steel was less significant than for the EC316LN stainless steel. In addition, strain-hardening behaviors were analyzed for EC316LN and 316L stainless steels. The strain-hardening rate of the 316 stainless steels was largely dependent on test temperature. It was estimated that the 316 stainless steels would retain more than 1% true stains to necking at 164 C after irradiation to 5 dpa. A calculation using reduction of area (RA) measurements and stress-strain data predicted positive strain hardening during plastic instability

  4. Optimization studies of photo-neutron production in high-Z metallic ...

    Indian Academy of Sciences (India)

    Monte Carlo calculations have been performed using MCNP code to study the optimization of photo-neutron yield for different electron beam energies impinging on Pb, W and Ta cylindrical targets of varying thickness. It is noticed that photo-neutron yield can be increased for electron beam energies ≥ 100 MeV for ...

  5. Optimization studies of photo-neutron production in high-Z metallic ...

    Indian Academy of Sciences (India)

    formation about the coupling of sub-critical assembly with neutron source [1–3]. .... where M,ρ and t are atomic mass, density and target thickness respectively. N0 ... tion Exchange Meeting on Actinide and Fission Product Partitioning and ...

  6. Energy distribution of the fast electron from Cu and CH targets irradiated with fs-laser pulses

    International Nuclear Information System (INIS)

    Cai Dafeng; Gu Yuqiu; Zheng Zhijian; Zhou Weimin; Jiao Chunye

    2014-01-01

    In order to investigate the effect of target's material on fast electron energy distribution, the energy distribution of fast electrons from the front and the rear of Cu and CH targets have been measured during the interaction of femtosecond laser-foil targets. The results show that the fast electron spectrums from the front of Cu and CH targets are similar, which show energy distribution of fast electrons depends very little on material of targets. The fast electron spectrums from the rear of Cu and CH targets are obviously dissimilar, which indicate a mighty effect of target material on fast electron transport. The fast electron spectrums from the Cu target is 'soften', which is due to electron recirculation and self-magnetic field produced by electrons transported in the target. The fast electron spectrums from the CH target is a Maxwellian distribution, which is due to collision effect when electrons transport in the target. (authors)

  7. Irradiation performance of HTGR fertile fuel in HFIR target capsules HT-12 through HT-15. Part I. Experiment description and fission product behavior

    International Nuclear Information System (INIS)

    Kania, M.J.; Lindemer, T.B.; Morgan, M.T.; Robbins, J.M.

    1977-02-01

    Sixteen types of Biso-coated designs, on ThO 2 kernels, were irradiated in High Flux Isotope Reactor target capsules HT-12 through HT-15. The report addresses the description of the experiment and extensive postirradiation analyses and experiments to determine fertile-particle burnup, fuel coating failures, and fission product behavior. Several low-temperature isotropic (LTI) pyrocarbon coatings, which ''survived'' according to visual inspection, were shown to have developed permeability during irradiation. These particles were irradiated at temperatures approximately equal to 1250 0 C and to burnups equal to or greater than 8 percent fission per initial heavy-metal atom (FIMA). No evidence of permeability was found in similar particles irradiated at temperatures approximately equal to 1550 0 C and burnups approximately equal to 16 percent FIMA. Failures due to permeability were not detectable by visual inspection but required a more extensive investigation by the 1000 0 C gaseous chlorine leaching technique. Maximum particle surface operating temperatures were found to be approximately 300 0 C in excess of design limits of 900 0 C (low-temperature magazines) and 1250 0 C (high-temperature magazines). The extremes of high temperatures and fast neutron fluences up to 1.6 x 10 22 neutrons/cm 2 produced severe degradation and swelling of the Poco graphite magazines and sample holders

  8. Effects of buried high-Z layers on fast electron propagation

    Czech Academy of Sciences Publication Activity Database

    Yang, X.; Xu, H.; Zhuo, H.; Ma, Y.; Shao, F.; Yin, Y.; Borghesi, Marco

    2014-01-01

    Roč. 68, č. 2 (2014), s. 1-7 ISSN 1434-6060 R&D Projects: GA MŠk ED1.1.00/02.0061; GA MŠk EE2.3.20.0279 Grant - others:ELI Beamlines(XE) CZ.1.05/1.1.00/02.0061; LaserZdroj (OP VK 3)(XE) CZ.1.07/2.3.00/20.0279 Institutional support: RVO:68378271 Keywords : laser-plasma interactions * short-pulse * hot-electrons * solid targets * transport * field Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.228, year: 2014

  9. KINEMATIC CLASSIFICATIONS OF LOCAL INTERACTING GALAXIES: IMPLICATIONS FOR THE MERGER/DISK CLASSIFICATIONS AT HIGH-z

    International Nuclear Information System (INIS)

    Hung, Chao-Ling; Larson, Kirsten L.; Sanders, D. B.; Rich, Jeffrey A.; Yuan, Tiantian; Kewley, Lisa J.; Casey, Caitlin M.; Smith, Howard A.; Hayward, Christopher C.

    2015-01-01

    The classification of galaxy mergers and isolated disks is key for understanding the relative importance of galaxy interactions and secular evolution during the assembly of galaxies. Galaxy kinematics as traced by emission lines have been used to suggest the existence of a significant population of high-z star-forming galaxies consistent with isolated rotating disks. However, recent studies have cautioned that post-coalescence mergers may also display disk-like kinematics. To further investigate the robustness of merger/disk classifications based on kinematic properties, we carry out a systematic classification of 24 local (U)LIRGs spanning a range of morphologies: from isolated spiral galaxies, ongoing interacting systems, to fully merged remnants. We artificially redshift the Wide Field Spectrograph observations of these local (U)LIRGs to z = 1.5 to make a realistic comparison with observations at high-z, and also to ensure that all galaxies have the same spatial sampling of ∼900 pc. Using both kinemetry-based and visual classifications, we find that the reliability of kinematic classification shows a strong trend with the interaction stage of galaxies. Mergers with two nuclei and tidal tails have the most distinct kinematics compared to isolated disks, whereas a significant population of the interacting disks and merger remnants are indistinguishable from isolated disks. The high fraction of mergers displaying disk-like kinematics reflects the complexity of the dynamics during galaxy interactions. Additional merger indicators such as morphological properties traced by stars or molecular gas are required to further constrain the merger/disk classifications at high-z

  10. Demonstration of Enhanced Radiation Drive in Hohlraums Made from a Mixture of High-Z Wall Materials

    International Nuclear Information System (INIS)

    Schein, Jochen; Jones, Ogden; Rosen, Mordecai; Dewald, Eduard; Glenzer, Siegfried; Gunther, Janelle; Hammel, Bruce; Landen, Otto; Suter, Laurence; Wallace, Russell

    2007-01-01

    We present results from experiments, numerical simulations and analytic modeling, demonstrating enhanced hohlraum performance. Care in the fabrication and handling of hohlraums with walls consisting of high-Z mixtures (cocktails) has led to our demonstration, for the first time, of a significant increase in radiation temperature compared to a pure Au hohlraum that is in agreement with predictions and is ascribable to reduced wall losses. The data suggest that a National Ignition Facility ignition hohlraum made of a U:Au:Dy cocktail should have ∼17% reduction in wall losses compared to a similar gold hohlraum

  11. An investigation of the opacity of high-Z mixture and implications for inertial confinement fusion hohlraum design

    International Nuclear Information System (INIS)

    Wang, P.; MacFarlane, J.J.; Orzechowski, T.J.

    1997-01-01

    We use an unresolved transition array model to investigate the opacities of high-Z materials and their mixtures which are of interest to indirect-drive inertial confinement fusion hohlraum design. In particular, we report on calculated opacities for pure Au, Gd, and Sm, as well as Au endash Sm and Au endash Gd mixtures. Our results indicate that mixtures of Au endash Gd and Au endash Sm can produce a significant enhancement in the Rosseland mean opacity. Radiation hydrodynamics simulations of Au radiation burnthrough are also presented, and compared with NOVA experimental data. copyright 1997 American Institute of Physics

  12. Effect of spatial nonuniformity of heating on compression and burning of a thermonuclear target under direct multibeam irradiation by a megajoule laser pulse

    Energy Technology Data Exchange (ETDEWEB)

    Bel’kov, S. A.; Bondarenko, S. V. [Russian Federal Nuclear Center, All-Russia Research Institute of Experimental Physics (Russian Federation); Vergunova, G. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Garanin, S. G. [Russian Federal Nuclear Center, All-Russia Research Institute of Experimental Physics (Russian Federation); Gus’kov, S. Yu.; Demchenko, N. N.; Doskoch, I. Ya. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation); Zmitrenko, N. V. [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Kuchugov, P. A., E-mail: pkuchugov@gmail.com; Rozanov, V. B.; Stepanov, R. V.; Yakhin, R. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)

    2017-02-15

    Direct-drive fusion targets are considered at present as an alternative to targets of indirect compression at a laser energy level of about 2 MJ. In this approach, the symmetry of compression and ignition of thermonuclear fuel play the major role. We report on the results of theoretical investigation of compression and burning of spherical direct-drive targets in the conditions of spatial nonuniformity of heating associated with a shift of the target from the beam center of focusing and possible laser radiation energy disbalance in the beams. The investigation involves numerous calculations based on a complex of 1D and 2D codes RAPID, SEND (for determining the target illumination and the dynamics of absorption), DIANA, and NUT (1D and multidimensional hydrodynamics of compression and burning of targets). The target under investigation had the form of a two-layer shell (ablator made of inertial material CH and DT ice) filled with DT gas. We have determined the range of admissible variation of compression and combustion parameters of the target depending on the variation of the spatial nonuniformity of its heating by a multibeam laser system. It has been shown that low-mode (long-wavelength) perturbations deteriorate the characteristics of the central region due to less effective conversion of the kinetic energy of the target shell into the internal energy of the center. Local initiation of burning is also observed in off-center regions of the target in the case of substantial asymmetry of irradiation. In this case, burning is not spread over the entire volume of the DT fuel as a rule, which considerably reduces the thermonuclear yield as compared to that in the case of spherical symmetry and central ignition.

  13. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

    Energy Technology Data Exchange (ETDEWEB)

    Azad, Arun, E-mail: arun.azad@bccancer.bc.ca [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Pathology, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Bukczynska, Patricia; Jackson, Susan [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Haput, Ygal; Cullinane, Carleen [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia); McArthur, Grant A.; Solomon, Benjamin [Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Division of Cancer Medicine, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Department of Medicine, St. Vincent' s Hospital, University of Melbourne, Parkville, Victoria (Australia); Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria (Australia)

    2014-02-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination.

  14. Co-targeting Deoxyribonucleic Acid–Dependent Protein Kinase and Poly(Adenosine Diphosphate-Ribose) Polymerase-1 Promotes Accelerated Senescence of Irradiated Cancer Cells

    International Nuclear Information System (INIS)

    Azad, Arun; Bukczynska, Patricia; Jackson, Susan; Haput, Ygal; Cullinane, Carleen; McArthur, Grant A.; Solomon, Benjamin

    2014-01-01

    Purpose: To examine the effects of combined blockade of DNA-dependent protein kinase (DNA-PK) and poly(adenosine diphosphate-ribose) polymerase-1 (PARP-1) on accelerated senescence in irradiated H460 and A549 non-small cell lung cancer cells. Methods and Materials: The effects of KU5788 and AG014699 (inhibitors of DNA-PK and PARP-1, respectively) on clonogenic survival, DNA double-strand breaks (DSBs), apoptosis, mitotic catastrophe, and accelerated senescence in irradiated cells were examined in vitro. For in vivo experiments, H460 xenografts established in athymic nude mice were treated with BEZ235 (a DNA-PK, ATM, and phosphatidylinositol 3-kinase/mammalian target of rapamycin inhibitor) and AG014699 to determine effects on proliferation, DNA DSBs, and accelerated senescence after radiation. Results: Compared with either inhibitor alone, combination treatment with KU57788 and AG014699 reduced postradiation clonogenic survival and significantly increased persistence of Gamma-H2AX (γH2AX) foci in irradiated H460 and A549 cells. Notably, these effects coincided with the induction of accelerated senescence in irradiated cells as reflected by positive β-galactosidase staining, G2-M cell-cycle arrest, enlarged and flattened cellular morphology, increased p21 expression, and senescence-associated cytokine secretion. In irradiated H460 xenografts, concurrent therapy with BEZ235 and AG014699 resulted in sustained Gamma-H2AX (γH2AX) staining and prominent β-galactosidase activity. Conclusion: Combined DNA-PK and PARP-1 blockade increased tumor cell radiosensitivity and enhanced the prosenescent properties of ionizing radiation in vitro and in vivo. These data provide a rationale for further preclinical and clinical testing of this therapeutic combination

  15. X-ray Spectroscopy of High-Z Elements on Nike

    Science.gov (United States)

    Aglitskiy, Y.; Weaver, J. L.; Karasik, M.; Serlin, V.; Obenschain, S. P.; Ralchenko, Yu.

    2013-10-01

    Survey X-ray spectrometer covering a spectral range from 0.5 to 19.5 angstroms has been added to the spectroscopic suite of Nike diagnostics. That allows simultaneous observation of both M- and N- spectra of W, Ta and Au with high spectral resolution. Low energy test shots confirmed strong presence of 3-4 transitions of Ni-like W, Ta and Au with X-ray energies as high as 3.5 keV when above mentioned elements were used as the targets. In our continuous effort to support DOE-NNSA's inertial fusion program, the future campaign will cover a wide range of plasma conditions that result in relatively energetic X-ray production. Eventually, absolutely calibrated spectrometers of similar geometry will be fielded at NIF in cooperation with NIF diagnostic group. Work supported by US DOE, Defense Programs.

  16. Influence of boronization on operation with high-Z plasma facing components in Alcator C-Mod

    International Nuclear Information System (INIS)

    Lipschultz, B.; Lin, Y.; Marmar, E.S.; Whyte, D.G.; Wukitch, S.; Hutchinson, I.H.; Irby, J.; LaBombard, B.; Reinke, M.L.; Terry, J.L.; Wright, G.

    2007-01-01

    We report the results of operation of Alcator C-Mod with all high-Z molybdenum plasma facing component (PFC) surfaces. Without boron-coated PFCs energy confinement was poor (H ITER,89 ∼ 1) due to high core molybdenum (n Mo /n e ≤ 0.1%) and radiation. After applying boron coatings, n Mo /n e was reduced by a factor of 10-20 with H ITER,89 approaching 2. Results of between-discharge boronization, localized at various major radii, point towards important molybdenum source regions being small, outside the divertor, and due to RF-sheath-rectification. Boronization also has a significant effect on the plasma startup phase lowering Z eff , radiation, and lowering the runaway electron damage. The requirement of low-Z coatings over at least a fraction of the Mo PFCs in C-Mod for best performance together with the larger than expected D retention in Mo, give impetus for further high-Z PFC investigations to better predict the performance of un-coated tungsten surfaces in ITER and beyond

  17. P2 Asymmetry of Au's M-band Flux and its smoothing effect due to high-Z ablator dopants

    Science.gov (United States)

    Li, Yongsheng; Zhai, Chuanlei; Ren, Guoli; Gu, Jianfa; Huo, Wenyi; Meng, Xujun; Ye, Wenhua; Lan, Ke; Zhang, Weiyan

    2017-10-01

    X-ray drive asymmetry is one of the main seeds of low-mode implosion asymmetry that blocks further improvement of the nuclear performance of ``high-foot'' experiments on the National Ignition Facility. More particularly, the P2 asymmetry of Au's M-band flux can also severely influence the implosion performance. Here we study the smoothing effect of mid- and/or high-Z dopants in ablator on M-band flux asymmetries, by modeling and comparing the implosion processes of a Ge-doped and a Si-doped ignition capsule driven by x-ray sources with asymmetric M-band flux. As the results, (1) mid- or high-Z dopants absorb M-band flux and re-emit isotropically, helping to smooth M-band flux arriving at the ablation front, therefore reducing the P2 asymmetries of the imploding shell and hot spot; (2) the smoothing effect of Ge-dopant is more remarkable than Si-dopant due to its higher opacity than the latter in Au's M-band; and (3) placing the doped layer at a larger radius in ablator is more efficient. Applying this effect may not be a main measure to reduce the low-mode implosion asymmetry, but might be of significance in some critical situations such as Inertial Confinement Fusion (ICF) experiments very near the performance cliffs of asymmetric x-ray drives.

  18. Proton irradiation parameters and chemical separation procedure for the bulk production of high-specific-activity {sup 186g}Re using WO{sub 3} targets

    Energy Technology Data Exchange (ETDEWEB)

    Fassbender, M.E.; Ballard, B.; Birnbaum, E.R. [Los Alamos National Laboratory, Los Alamos, NM (United States). Chemistry Div.] [and others

    2013-08-01

    Rhenium-186g (T{sub 1/2} = 89.2 h) is a {beta}{sup -} emitter suitable for therapeutic applications. Current production methods rely on reactor production via {sup 185}Re(n,{gamma}) which results in low specific activities, thereby limiting its use. Production by p,d activation of enriched {sup 186}W results in a {sup 186g}Re product with a higher specific activity, allowing it to be used for targeted therapy with limited receptors. A test target consisting of pressed, sintered {sup nat}WO{sub 3} was proton irradiated at Los Alamos (LANL-IPF) to evaluate product yield and impurities, irradiation parameters and wet chemical Re recovery for proof-of-concept for bulk production of {sup 186g}Re. We demonstrated isolation of {sup 186g}Re in 97% yield from irradiated {sup nat}WO{sub 3} targets within 12 h of end of bombardment (EOB) via an alkaline dissolution followed by anion exchange. The recovery process has potential for automation, and WO{sub 3} can be easily recycled for recurrent irradiations. A {sup 186g}Re batch yield of 42.7 {+-} 2.2 {mu}Ci/{mu}Ah or 439 {+-} 23 MBq/C was obtained after 24 h in an 18.5 {mu}A proton beam. The target entrance energy was determined to be 15.6 MeV. The specific activity of {sup 186g}Re at EOB was measured to be 1.9 kCi (70.3 TBq) mmol{sup -1}, which agrees well with the result of a previous {sup 185,186m}Re co-production EMPIRE and TALYS modeling study assuming similar conditions. Utilizing enriched {sup 186}WO{sub 3}, we anticipate that a proton beam of 250 {mu}A for 24 h will provide batch yields of 256 mCi (9.5 GBq) of {sup 186g}Re at EOB with specific activities even higher than 1.9 kCi (70.3 TBq) mmol{sup -1}, suitable for therapy applications. (orig.)

  19. INTERACTION OF LASER RADIATION WITH MATTER AND OTHER LASER APPLICATIONS: Changes in the emission properties of metal targets during pulse-periodic laser irradiation

    Science.gov (United States)

    Konov, Vitalii I.; Pimenov, S. M.; Prokhorov, A. M.; Chapliev, N. I.

    1988-02-01

    A scanning electron microscope was used with a pulse-periodic CO2 laser to discover the laws governing the correlation of the modified microrelief of metal surfaces, subjected to the action of multiple laser pulses, with the emission of charged particles and the luminescence of the irradiated zone. It was established that the influence of sorption and laser-induced desorption on the emission signals may be manifested differently depending on the regime of current generation in the "target-vacuum chamber" circuit.

  20. THE SUBARU HIGH-z QUASAR SURVEY: DISCOVERY OF FAINT z ∼ 6 QUASARS

    International Nuclear Information System (INIS)

    Kashikawa, Nobunari; Furusawa, Hisanori; Niino, Yuu; Ishizaki, Yoshifumi; Onoue, Masafusa; Toshikawa, Jun; Ishikawa, Shogo; Willott, Chris J.; Im, Myungshin; Shimasaku, Kazuhiro; Ouchi, Masami; Hibon, Pascale

    2015-01-01

    We present the discovery of one or two extremely faint z ∼ 6 quasars in 6.5 deg 2 utilizing a unique capability of the wide-field imaging of the Subaru/Suprime-Cam. The quasar selection was made in (i'-z B ) and (z B -z R ) colors, where z B and z R are bandpasses with central wavelengths of 8842 Å and 9841 Å, respectively. The color selection can effectively isolate quasars at z ∼ 6 from M/L/T dwarfs without the J-band photometry down to z R < 24.0, which is 3.5 mag deeper than the Sloan Digital Sky Survey (SDSS). We have selected 17 promising quasar candidates. The follow-up spectroscopy for seven targets identified one apparent quasar at z = 6.156 with M 1450 = –23.10. We also identified one possible quasar at z = 6.041 with a faint continuum of M 1450 = –22.58 and a narrow Lyα emission with HWHM =427 km s –1 , which cannot be distinguished from Lyman α emitters. We derive the quasar luminosity function at z ∼ 6 by combining our faint quasar sample with the bright quasar samples by SDSS and CFHQS. Including our data points invokes a higher number density in the faintest bin of the quasar luminosity function than the previous estimate employed. This suggests a steeper faint-end slope than lower z, though it is yet uncertain based on a small number of spectroscopically identified faint quasars, and several quasar candidates still remain to be diagnosed. The steepening of the quasar luminosity function at the faint end does increase the expected emission rate of the ionizing photon; however, it only changes by a factor of approximately two to six. This was found to still be insufficient for the required photon budget of reionization at z ∼ 6

  1. Methods for chemical recovery of non-carrier-added radioactive tin from irradiated intermetallic Ti-Sb targets

    Science.gov (United States)

    Lapshina, Elena V [Troitsk, RU; Zhuikov, Boris L [Troitsk, RU; Srivastava, Suresh C [Setauket, NY; Ermolaev, Stanislav V [Obninsk, RU; Togaeva, Natalia R [Obninsk, RU

    2012-01-17

    The invention provides a method of chemical recovery of no-carrier-added radioactive tin (NCA radiotin) from intermetallide TiSb irradiated with accelerated charged particles. An irradiated sample of TiSb can be dissolved in acidic solutions. Antimony can be removed from the solution by extraction with dibutyl ether. Titanium in the form of peroxide can be separated from tin using chromatography on strong anion-exchange resin. In another embodiment NCA radiotin can be separated from iodide solution containing titanium by extraction with benzene, toluene or chloroform. NCA radiotin can be finally purified from the remaining antimony and other impurities using chromatography on silica gel. NCA tin-117m can be obtained from this process. NCA tin-117m can be used for labeling organic compounds and biological objects to be applied in medicine for imaging and therapy of various diseases.

  2. An analytic solution for calculating the beam intensity profiles useful to irradiate target volumes with bi-concave outlines

    Energy Technology Data Exchange (ETDEWEB)

    De Neve, W; Derycke, S; De Wagter, C [Ghent Rijksuniversiteit (Belgium). Kliniek voor Radiotherapie en Kerngeneeskunde

    1995-12-01

    A heuristic planing procedure allowing to obtain a 3-dimensional conformal dose distribution in radiotherapy for target volumes with a bi-concave or multi-concave shape has been developed. The described method is tested on a phantom simulating a pelvic target, described by Brahme.

  3. Re-irradiation after gross total resection of recurrent glioblastoma. Spatial pattern of recurrence and a review of the literature as a basis for target volume definition

    Energy Technology Data Exchange (ETDEWEB)

    Straube, Christoph; Elpula, Greeshma [Technische Universitaet Muenchen (TUM), Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Gempt, Jens; Gerhardt, Julia; Meyer, Bernhard [Technische Universitaet Muenchen (TUM), Department of Neurosurgery, Klinikum rechts der Isar, Muenchen (Germany); Bette, Stefanie; Zimmer, Claus [Technische Universitaet Muenchen (TUM), Department of Neuroradiology, Klinikum rechts der Isar, Muenchen (Germany); Schmidt-Graf, Friederike [Technische Universitaet Muenchen (TUM), Department of Neurology, Klinikum rechts der Isar, Muenchen (Germany); Combs, Stephanie E. [Technische Universitaet Muenchen (TUM), Department of Radiation Oncology, Klinikum rechts der Isar, Muenchen (Germany); Helmholtz Zentrum Muenchen, Institute for Innovative Radiotherapy (iRT), Department of Radiation Sciences (DRS), Oberschleissheim (Germany)

    2017-11-15

    Currently, patients with gross total resection (GTR) of recurrent glioblastoma (rGBM) undergo adjuvant chemotherapy or are followed up until progression. Re-irradiation, as one of the most effective treatments in macroscopic rGBM, is withheld in this situation, as uncertainties about the pattern of re-recurrence, the target volume, and also the efficacy of early re-irradiation after GTR exist. Imaging and clinical data from 26 consecutive patients with GTR of rGBM were analyzed. The spatial pattern of recurrences was analyzed according to the RANO-HGG criteria (''response assessment in neuro-oncology criteria for high-grade gliomas''). Progression-free (PFS) and overall survival (OS) were analyzed by the Kaplan-Meier method. Furthermore, a systematic review was performed in PubMed. All but 4 patients underwent adjuvant chemotherapy after GTR. Progression was diagnosed in 20 of 26 patients and 70% of recurrent tumors occurred adjacent to the resection cavity. The median extension beyond the edge of the resection cavity was 20 mm. Median PFS was 6 months; OS was 12.8 months. We propose a target volume containing the resection cavity and every contrast enhancing lesion as the gross tumor volume (GTV), a spherical margin of 5-10 mm to generate the clinical target volume (CTV), and a margin of 1-3 mm to generate the planning target volume (PTV). Re-irradiation of this volume is deemed to be safe and likely to prolong PFS. Re-irradiation is worth considering also after GTR, as the volumes that need to be treated are limited and re-irradiation has already proven to be a safe treatment option in general. The strategy of early re-irradiation is currently being tested within the GlioCave/NOA 17/Aro 2016/03 trial. (orig.) [German] Patienten mit einem rezidivierten Glioblastom (rGBM) werden, wenn eine komplette Resektion (GTR) des makroskopischen Rezidivs durchgefuehrt wurde, aktuell meist systemisch adjuvant behandelt oder einer engmaschigen Nachsorge

  4. Transition from equilibrium ignition to non-equilibrium burn for ICF capsules surrounded by a high-Z pusher

    International Nuclear Information System (INIS)

    Li, Ji W.; Chang, Lei; Li, Yun S.; Li, Jing H.

    2011-01-01

    For the ICF capsule surrounded by a high-Z pusher which traps the radiation and confines the hot fuel, the fuel will first be ignited in thermal equilibrium with radiation at a much lower temperature than hot-spot ignition, which is also the low temperature ignition. Because of the lower areal density for ICF capsules, the equilibrium ignition must be developed into a non-equilibrium burn to shorten the reaction time and lower the drive energy. In this paper, the transition from the equilibrium ignition to non-equilibrium burn is discussed and the energy deposited by α particles required for the equilibrium ignition and non-equilibrium burn to occur is estimated.

  5. Direct measurement of two-electron contributions to the ground state energy of heliumlike high-Z ions

    International Nuclear Information System (INIS)

    Stoehlker, T.; Elliott, S.R.; Marrs, R.E.

    1995-09-01

    We report on a novel technique which exploits Radiative Recombination transitions for a direct experimental determination of the two-electron contributions to the ground state energy in heliumlike high-Z ions. Results are presented of a first experiment which was conducted at an electron beam ion trap for various elements ranging from Z=32 to 83. The comparison with theoretical predictions demonstrates that the achieved precision already provides a sensitive test of second order manybody contributions and approaches the size of the two-electron (screened) Lamb shift. The ptoential of the new technique will be outlined and the capability of the ESR storage ring for future investigations will be emphasized. (orig.)

  6. Measurements of neutron spectrum from stopping-length target irradiated by several tens-MeV/u particles

    Energy Technology Data Exchange (ETDEWEB)

    Meigo, Shin-ichiro; Takada, Hiroshi; Nakashima, Hiroshi; Sasa, Toshinobu [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Tanaka, Susumu; Shin, Kazuo; Ono, Shinji

    1997-03-01

    Using a Time-of-Flight technique, we have measured neutron spectra from stopping-length targets bombarded with 68-MeV protons and 100-MeV {alpha}-particles. The measured spectra were used to validate the results calculated by the Quantum Molecular Dynamics (QMD) plus Statistical Decay Model (SDM). The results of QMD plus SDM code agreed fairly well with the experimental data for the light target. On the other hand, the QMD plus SDM gives a larger value than the experimental for the heavy target. (author)

  7. P2 asymmetry of Au's M-band flux and its smoothing effect due to high-Z ablator dopants

    Directory of Open Access Journals (Sweden)

    Yongsheng Li

    2017-03-01

    Full Text Available X-ray drive asymmetry is one of the main seeds of low-mode implosion asymmetry that blocks further improvement of the nuclear performance of “high-foot” experiments on the National Ignition Facility [Miller et al., Nucl. Fusion 44, S228 (2004]. More particularly, the P2 asymmetry of Au's M-band flux can also severely influence the implosion performance of ignition capsules [Li et al., Phys. Plasmas 23, 072705 (2016]. Here we study the smoothing effect of mid- and/or high-Z dopants in ablator on Au's M-band flux asymmetries, by modeling and comparing the implosion processes of a Ge-doped ignition capsule and a Si-doped one driven by X-ray sources with P2 M-band flux asymmetry. As the results, (1 mid- or high-Z dopants absorb hard X-rays (M-band flux and re-emit isotropically, which helps to smooth the asymmetric M-band flux arriving at the ablation front, therefore reducing the P2 asymmetries of the imploding shell and hot spot; (2 the smoothing effect of Ge-dopant is more remarkable than Si-dopant because its opacity in Au's M-band is higher than the latter's; and (3 placing the doped layer at a larger radius in ablator is more efficient. Applying this effect may not be a main measure to reduce the low-mode implosion asymmetry, but might be of significance in some critical situations such as inertial confinement fusion (ICF experiments very near the performance cliffs of asymmetric X-ray drives.

  8. Temperature effects on the mechanical properties of candidate SNS target container materials after proton and neutron irradiation

    International Nuclear Information System (INIS)

    Byun, T.S.; Farrell, K.; Lee, E.H.; Mansur, L.K.; Maloy, S.A.; James, M.R.; Johnson, W.R.

    2002-01-01

    This report presents the tensile properties of EC316LN austenitic stainless steel and 9Cr-2WVTa ferritic/martensitic steel after 800 MeV proton and spallation neutron irradiation to doses in the range 0.54-2.53 dpa at 30-100 deg. C. Tensile testing was performed at room temperature (20 deg. C) and 164 deg. C. The EC316LN stainless steel maintained notable strain-hardening capability after irradiation, while the 9Cr-2WVTa ferritic/martensitic steel posted negative hardening in the engineering stress-strain curves. In the EC316LN stainless steel, increasing the test temperature from 20 to 164 deg. C decreased the strength by 13-18% and the ductility by 8-36%. The effect of test temperature for the 9Cr-2WVTa ferritic/martensitic steel was less significant than for the EC316LN stainless steel. In addition, strain-hardening behaviors were analyzed for EC316LN and 316L stainless steels. The strain-hardening rate of the 316 stainless steels was largely dependent on test temperature. A calculation using reduction of area measurements and stress-strain data predicted positive strain hardening during plastic instability

  9. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Lar' kin, A., E-mail: alexeylarkin@yandex.ru; Uryupina, D.; Ivanov, K.; Savel' ev, A., E-mail: abst@physics.msu.ru [International Laser Center and Faculty of Physics, Lomonosov Moscow State University, Moscow 119991 (Russian Federation); Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M. [Centre d' Études Nucléaires de Bordeaux-Gradignan, University of Bordeaux-CNRS-IN2P3, 33170 Gradignan (France); Spohr, K. [School of Engineering, University of the West of Scotland, Paisley, Scotland PA1 2BE (United Kingdom); Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T. [Centre Lasers Intenses et Applications, University of Bordeaux-CNRS-CEA, Talence 33405 (France)

    2014-09-15

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition.

  10. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    International Nuclear Information System (INIS)

    Lar'kin, A.; Uryupina, D.; Ivanov, K.; Savel'ev, A.; Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M.; Spohr, K.; Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T.

    2014-01-01

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition

  11. Microjet formation and hard x-ray production from a liquid metal target irradiated by intense femtosecond laser pulses

    Science.gov (United States)

    Lar'kin, A.; Uryupina, D.; Ivanov, K.; Savel'ev, A.; Bonnet, T.; Gobet, F.; Hannachi, F.; Tarisien, M.; Versteegen, M.; Spohr, K.; Breil, J.; Chimier, B.; Dorchies, F.; Fourment, C.; Leguay, P.-M.; Tikhonchuk, V. T.

    2014-09-01

    By using a liquid metal as a target one may significantly enhance the yield of hard x-rays with a sequence of two intense femtosecond laser pulses. The influence of the time delay between the two pulses is studied experimentally and interpreted with numerical simulations. It was suggested that the first arbitrary weak pulse produces microjets from the target surface, while the second intense pulse provides an efficient electron heating and acceleration along the jet surface. These energetic electrons are the source of x-ray emission while striking the target surface. The microjet formation is explained based on the results given by both optical diagnostics and hydrodynamic modeling by a collision of shocks originated from two distinct zones of laser energy deposition.

  12. Highly ionized plasma plume generation by long-pulse CO2 laser irradiation of solid targets in strong axial magnetic fields

    International Nuclear Information System (INIS)

    Hoffman, A.L.; Crawford, E.A.

    1982-01-01

    The present work utilizes high f number optics and is directed primarily at controlling the conditions in the magnetically confined plume. Typically, fully ionized carbon plasmas have been produced with 10 18 cm -3 electron densities and 100 to 150 eV electron temperatures. These carbon plasmas have been doped with high Z atoms in order to study ionization and emission rates at the above conditions

  13. Role of Hypoxia-inducible factor-1 and its target genes in human lung adenocarcinoma cells after photon- versus carbon ion irradiation; Expression HIF-1-abhaengiger Gene in humanen Lungenadenokarzinom (A549)-Zellen und deren Regulation nach Photonen- und Schwerionenbestrahlung

    Energy Technology Data Exchange (ETDEWEB)

    Bill, Verena Maria

    2013-11-26

    Exposed to hypoxia tumor cells are notably resistant to photon irradiation. The hypoxiainducible transcription factor 1α (HIF-1α) seems to play a fundamental role in this resistance, while its role after heavy-ion beam remains unknown. The intention of this study was to determine how A549-cells (non-small-cell lung carcinoma) react in different oxygenation states after irradiation with photons or heavy ions, particularly in regards to their expression of HIF-1 target genes. Resistance of hypoxic A549 cells after photon irradiation was documented by cellular and clonogenic survival. In contrast, cellular survival after heavy-ion irradiation in hypoxic cells was not elevated to normoxic cells. Among the oxygen dependent regulation of HIF-1 target genes, gene expression analyses showed an increased expression of GLUT-1, LDH-A, PDK-1 and VEGF after photon irradiation but not after heavy-ion irradiation after 48 hours in normoxic cells. As expected, CDKN1A as inhibitor of cell cycle progression showed higher expression after both radiation forms; interestingly CDKN1A was also in an oxygen dependent manner lightly upregulated. In western blot analyses we demonstrated a significant increase of HIF-1 and GLUT-1 caused by hypoxia, but only a tendency of increased protein level in hypoxia after photon irradiation and no changes after heavy-ion irradiation. Significantly higher protein level of secreted VEGF-A could be measured 72 hours after photon irradiation in normoxic cells by ELISA analyses. Controversially discussed, I could not detect an association between HIF-1 and SCF or Trx-1 in A549-cells in this study. Whereas Trx-1-expression was neither influenced by changed oxygen partial pressure nor irradiation, I could show increased SCF mRNA by quantitative Real Time-PCR and secreted protein level by ELISA after photon irradiation independent of oxygen state. In summary, this study showed that HIF-1 and its target genes (GLUT-1, LDHA; PDK, VEGF) and also SCF was

  14. Coupling of morphology to surface transport in ion-beam-irradiated surfaces: normal incidence and rotating targets

    International Nuclear Information System (INIS)

    Munoz-Garcia, Javier; Cuerno, Rodolfo; Castro, Mario

    2009-01-01

    Continuum models have proved their applicability to describe nanopatterns produced by ion-beam sputtering of amorphous or amorphizable targets at low and medium energies. Here we pursue the recently introduced 'hydrodynamic approach' in the cases of bombardment at normal incidence, or of oblique incidence onto rotating targets, known to lead to self-organized arrangements of nanodots. Our approach stresses the dynamical roles of material (defect) transport at the target surface and of local redeposition. By applying results previously derived for arbitrary angles of incidence, we derive effective evolution equations for these geometries of incidence, which are then numerically studied. Moreover, we show that within our model these equations are identical (albeit with different coefficients) in both cases, provided surface tension is isotropic in the target. We thus account for the common dynamics for both types of incidence conditions, namely formation of dots with short-range order and long-wavelength disorder, and an intermediate coarsening of dot features that improves the local order of the patterns. We provide for the first time approximate analytical predictions for the dependence of stationary dot features (amplitude and wavelength) on phenomenological parameters, that improve upon previous linear estimates. Finally, our theoretical results are discussed in terms of experimental data.

  15. HDR monotherapy for prostate cancer: A simulation study to determine the effect of catheter displacement on target coverage and normal tissue irradiation

    International Nuclear Information System (INIS)

    Kolkman-Deurloo, Inger-Karine K.; Roos, Martin A.; Aluwini, Shafak

    2011-01-01

    Purpose: The aim of this study was to systematically analyse the effect of catheter displacements both on target coverage and normal tissue irradiation in fractionated high dose rate (HDR) prostate brachytherapy, using a simulation study, and to define tolerances for catheter displacement ensuring that both target coverage and normal tissue doses remain clinically acceptable. Besides the effect of total implant displacement, also displacements of catheters belonging to selected template rows only were evaluated in terms of target coverage and normal tissue dose, in order to analyse the change in dose distribution as a function of catheter dwell weight and catheter location. Material and methods: Five representative implant geometries, with 17 catheters each, were selected. The clinical treatment plan was compared to treatment plans in which an entire implant displacement in caudal direction over 3, 5, 7 and 10 mm was simulated. Besides, treatment plans were simulated considering a displacement of either the central, most ventral or most dorsal catheter rows only, over 5 mm caudally. Results: Due to displacement of the entire implant the target coverage drops below the tolerance of 93% for all displacements studied. The effect of displacement of the entire implant on organs at risk strongly depended on the patient anatomy; e.g., for 80% of the implant geometries the V 80 of the rectum exceeded its tolerance for all displacements. The effect of displacement of catheters belonging to selected template rows depended strongly on the relative weight of each catheter row when considering the target coverage and on its location when considering the dose in the organs at risk. Conclusion: This study supports the need for a check of the catheter locations before each fraction and correction of deviations of the catheter position exceeding 3 mm.

  16. Relapse patterns after radiochemotherapy of glioblastoma with FET PET-guided boost irradiation and simulation to optimize radiation target volume

    International Nuclear Information System (INIS)

    Piroth, Marc D.; Galldiks, Norbert; Pinkawa, Michael; Holy, Richard; Stoffels, Gabriele; Ermert, Johannes; Mottaghy, Felix M.; Shah, N. Jon; Langen, Karl-Josef; Eble, Michael J.

    2016-01-01

    O-(2-18 F-fluoroethyl)-L-tyrosine-(FET)-PET may be helpful to improve the definition of radiation target volumes in glioblastomas compared with MRI. We analyzed the relapse patterns in FET-PET after a FET- and MRI-based integrated-boost intensity-modulated radiotherapy (IMRT) of glioblastomas to perform an optimized target volume definition. A relapse pattern analysis was performed in 13 glioblastoma patients treated with radiochemotherapy within a prospective phase-II-study between 2008 and 2009. Radiotherapy was performed as an integrated-boost intensity-modulated radiotherapy (IB-IMRT). The prescribed dose was 72 Gy for the boost target volume, based on baseline FET-PET (FET-1) and 60 Gy for the MRI-based (MRI-1) standard target volume. The single doses were 2.4 and 2.0 Gy, respectively. Location and volume of recurrent tumors in FET-2 and MRI-2 were analyzed related to initial tumor, detected in baseline FET-1. Variable target volumes were created theoretically based on FET-1 to optimally cover recurrent tumor. The tumor volume overlap in FET and MRI was poor both at baseline (median 12 %; range 0–32) and at time of recurrence (13 %; 0–100). Recurrent tumor volume in FET-2 was localized to 39 % (12–91) in the initial tumor volume (FET-1). Over the time a shrinking (mean 12 (5–26) ml) and shifting (mean 6 (1–10 mm) of the resection cavity was seen. A simulated target volume based on active tumor in FET-1 with an additional safety margin of 7 mm around the FET-1 volume covered recurrent FET tumor volume (FET-2) significantly better than a corresponding target volume based on contrast enhancement in MRI-1 with a same safety margin of 7 mm (100 % (54–100) versus 85 % (0–100); p < 0.01). A simulated planning target volume (PTV), based on FET-1 and additional 7 mm margin plus 5 mm margin for setup-uncertainties was significantly smaller than the conventional, MR-based PTV applied in this study (median 160 (112–297) ml versus 231 (117–386) ml, p < 0

  17. Signal enhancement due to high-Z nanofilm electrodes in parallel plate ionization chambers with variable microgaps.

    Science.gov (United States)

    Brivio, Davide; Sajo, Erno; Zygmanski, Piotr

    2017-12-01

    We developed a method for measuring signal enhancement produced by high-Z nanofilm electrodes in parallel plate ionization chambers with variable thickness microgaps. We used a laboratory-made variable gap parallel plate ionization chamber with nanofilm electrodes made of aluminum-aluminum (Al-Al) and aluminum-tantalum (Al-Ta). The electrodes were evaporated on 1 mm thick glass substrates. The interelectrode air gap was varied from 3 μm to 1 cm. The gap size was measured using a digital micrometer and it was confirmed by capacitance measurements. The electric field in the chamber was kept between 0.1 kV/cm and 1 kV/cm for all the gap sizes by applying appropriate compensating voltages. The chamber was exposed to 120 kVp X-rays. The current was measured using a commercial data acquisition system with temporal resolution of 600 Hz. In addition, radiation transport simulations were carried out to characterize the dose, D(x), high-energy electron current, J(x), and deposited charge, Q(x), as a function of distance, x, from the electrodes. A deterministic method was selected over Monte Carlo due to its ability to produce results with 10 nm spatial resolution without stochastic uncertainties. Experimental signal enhancement ratio, SER(G) which we defined as the ratio of signal for Al-air-Ta to signal for Al-air-Al for each gap size, was compared to computations. The individual contributions of dose, electron current, and charge deposition to the signal enhancement were determined. Experimental signals matched computed data for all gap sizes after accounting for several contributions to the signal: (a) charge carrier generated via ionization due to the energy deposited in the air gap, D(x); (b) high-energy electron current, J(x), leaking from high-Z electrode (Ta) toward low-Z electrode (Al); (c) deposited charge in the air gap, Q(x); and (d) the decreased collection efficiency for large gaps (>~500 μm). Q(x) accounts for the electrons below 100 eV, which are

  18. Laser stand for irradiation of targets by laser pulses from the Iskra-5 facility at a repetition rate of 100 MHz

    International Nuclear Information System (INIS)

    Annenkov, V I; Garanin, Sergey G; Eroshenko, V A; Zhidkov, N V; Zubkov, A V; Kalipanov, S V; Kalmykov, N A; Kovalenko, V P; Krotov, V A; Lapin, S G; Martynenko, S P; Pankratov, V I; Faizullin, V S; Khrustalev, V A; Khudikov, N M; Chebotar, V S

    2009-01-01

    A train of a few tens of high-power subnanosecond laser pulses with a repetition period of 10 ns is generated in the Iskra-5 facility. The laser pulse train has an energy of up to 300 J and contains up to 40 pulses (by the 0.15 intensity level), the single pulse duration in the train being ∼0.5 ns. The results of experiments on conversion of a train of laser pulses to a train of X-ray pulses are presented. Upon irradiation of a tungsten target, a train of X-ray pulses is generated with the shape of an envelope in the spectral band from 0.18 to 0.28 keV similar to that of the envelope of the laser pulse train. The duration of a single X-ray pulse in the train is equal to that of a single laser pulse. (lasers)

  19. Note: Proton irradiation at kilowatt-power and neutron production from a free-surface liquid-lithium target

    Energy Technology Data Exchange (ETDEWEB)

    Halfon, S.; Feinberg, G. [Soreq NRC, Yavne 81800 (Israel); Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel); Arenshtam, A.; Kijel, D.; Weissman, L.; Aviv, O.; Berkovits, D.; Dudovitch, O.; Eisen, Y.; Eliyahu, I.; Haquin, G.; Hazenshprung, N.; Kreisel, A.; Mardor, I.; Shimel, G.; Shor, A.; Silverman, I.; Yungrais, Z. [Soreq NRC, Yavne 81800 (Israel); Paul, M., E-mail: paul@vms.huji.ac.il; Tessler, M. [Racah Institute of Physics, Hebrew University, Jerusalem 91904 (Israel)

    2014-05-15

    The free-surface Liquid-Lithium Target, recently developed at Soreq Applied Research Accelerator Facility (SARAF), was successfully used with a 1.9 MeV, 1.2 mA (2.3 kW) continuous-wave proton beam. Neutrons (∼2 × 10{sup 10} n/s having a peak energy of ∼27 keV) from the {sup 7}Li(p,n){sup 7}Be reaction were detected with a fission-chamber detector and by gold activation targets positioned in the forward direction. The setup is being used for nuclear astrophysics experiments to study neutron-induced reactions at stellar energies and to demonstrate the feasibility of accelerator-based boron neutron capture therapy.

  20. Volatile elements production rates in a 1.4 Gev proton-irradiated molten lead-bismuth target

    CERN Document Server

    Zanini, L; Everaerts, P; Fallot, M; Franberg, H; Gröschel, F; Jost, C; Kirchner, T; Kojima, Y; Köster, U; Lebenhaft, J; Manfrina, E; Pitcher, E J; Ravn, H L; Tall, Y; Wagner, W; Wohlmuther, M

    2005-01-01

    Production rates of volatile elements following spallation reaction of 1.4 GeV protons on a liquid Pb/Bi target have been measured. The experiment was performed at the ISOLDE facility at CERN. These data are of interest for the developments of targets for accelerator driven systems such as MEGAPIE. Additional data have been taken on a liquid Pb target. Calculations were performed using the FLUKA and MCNPX Monte Carlo codes coupled with the evolution codes ORIHET3 and FISPACT using different options for the intra-nuclear cascades and evaporation models. Preliminary results from the data analysis show good comparison with calculations for Hg and for noble gases. For other elements such as I it is apparent that only a fraction of the produced isotopes is released. The agreement with the experimental data varies depending on the model combination used. The best results are obtained using MCNPX with the INCL4/ABLA models and with FLUKA. Discrepancies are found for some isotopes produced by fission using the MCNPX ...

  1. Measurement of L3 subshell absorption jump ratios and jump factors for high Z elements using EDXRF technique

    International Nuclear Information System (INIS)

    Kaçal, M.R.

    2014-01-01

    Energy dispersive X-ray fluorescence technique (EDXRF) has been employed for measuring L 3 -subshell absorption jump ratios, r L 3 and jump factors, J L 3 for high Z elements. Jump factors and jump ratios for these elements have been determined by measuring L 3 subshell fluorescence parameters such as L 3 subshell X-ray production cross section σ L 3 , L 3 subshell fluorescence yield, ω L 3 , total L 3 subshell and higher subshells photoionization cross section σ L T . Measurements were performed using a Cd-109 radioactive point source and an Si(Li) detector in direct excitation experimental geometry. Measured values for jump factors and jump ratios have been compared with theoretically calculated and other experimental values. - Highlights: • This paper regards L 3 subshell absorption jump ratios and jump factors using the EDXRF method. • These parameters were measured using a new method. • This method is more useful than other methods which require much effort. • Results are in good agreement with theoretical and experimental values

  2. Non-LTE modeling of the radiative properties of high-Z plasma using linear response methodology

    Science.gov (United States)

    Foord, Mark; Harte, Judy; Scott, Howard

    2017-10-01

    Non-local thermodynamic equilibrium (NLTE) atomic processes play a key role in the radiation flow and energetics in highly ionized high temperature plasma encountered in inertial confinement fusion (ICF) and astrophysical applications. Modeling complex high-Z atomic systems, such as gold used in ICF hohlraums, is particularly challenging given the complexity and intractable number of atomic states involved. Practical considerations, i.e. speed and memory, in large radiation-hydrodynamic simulations further limit model complexity. We present here a methodology for utilizing tabulated NLTE radiative and EOS properties for use in our radiation-hydrodynamic codes. This approach uses tabulated data, previously calculated with complex atomic models, modified to include a general non-Planckian radiation field using a linear response methodology. This approach extends near-LTE response method to conditions far from LTE. Comparisons of this tabular method with in-line NLTE simulations of a laser heated 1-D hohlraum will be presented, which show good agreement in the time-evolution of the plasma conditions. This work was performed under the auspices of the U.S. Dept. of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  3. Charge exchange (p,n) reactions to the isobaric analog states of high Z nuclei: 73< or =Z< or =92

    International Nuclear Information System (INIS)

    Hansen, L.F.; Grimes, S.M.; Poppe, C.H.; Wong, C.

    1983-01-01

    Differential cross sections have been measured for the (p,n) reaction to the isobaric analog states of 181 Ta, 197 Au, 209 Bi, 232 Th, and 238 U at an incident energy of 27 MeV. Because of the importance of collective effects in this mass region, coupled-channel calculations have been carried out in the analysis of the data. Optical potentials obtained from the Lane model for the charge exchange reaction have been used in the simultaneous analysis of coupled proton and neutron channels. The sensitivity of the calculations to the different couplings between the levels and to the magnitude of the isovector potentials, V 1 and W 1 , is discussed. The good agreement obtained between the measured and calculated (p,n) angular distributions to the analog state confirms the validity of the Lane formalism for high-Z nuclei (Z> or =50). Elastic neutron differential cross sections inferred from the coupled-channel analysis are compared with measurements available in the literature in the energy range 7--8 MeV. The results of these calculations agree with the measured values as well as the results of calculations made using global neutron optical potential parameters optimized to fit neutron data

  4. THE ORIGIN OF COLOR GRADIENTS IN EARLY-TYPE SYSTEMS AND THEIR COMPACTNESS AT HIGH-z

    International Nuclear Information System (INIS)

    La Barbera, F.; De Carvalho, R. R.

    2009-01-01

    In this Letter, we present mean optical+NIR color gradient estimates for 5080 early-type galaxies (ETGs) in the grizY JHK wavebands of the Sloan Digital Sky Survey plus the UKIRT Infrared Deep Sky Survey. The color gradient is estimated as the logarithmic slope of the radial color profile in ETGs. With such a large sample size, we study the variation of the mean color gradient as a function of waveband with unprecedented accuracy. We find that (1) color gradients are mainly due, on average, to a metallicity variation of about -0.4 dex per decade in galaxy radius; and (2) a small, but significant, positive age gradient is present, on average, in ETGs, with the inner stellar population being slightly younger, by ∼0.1 dex per radial decade, than the outer one. Also, we show that the presence of a positive mean age gradient in ETGs, as found in the present study, implies their effective radius to be smaller at high-z, consistent with observations.

  5. Identification of High-Z Materials With Photoneutrons Driven by a Low-Energy Electron Linear Accelerator

    Science.gov (United States)

    Yang, Yigang; Zhang, Zhi; Chen, Huaibi; Li, Yulan; Li, Yuanjing

    2017-07-01

    Contraband-detection systems can use X-rays and photoneutrons delivered from the same 7-MeV electron linear accelerator (e-LINAC) to stimulate and extract information from inspected materials. The X-ray attenuation information is used to measure the mass thickness, which is combined with the photoneutron attenuation information to categorize inspected materials as common organic materials, metals, and heavy metals. Once a heavy metal is found, the beta-delayed neutrons stimulated by the (γ,fission) reaction are measured by a polyethylene-moderated 3He counter to clarify if the material is fissile. The presence of neutron events 2000 μs after the X-ray pulse confirms the existence of the fissile material. The isotopes in the material are then identified using the time-of-flight method to analyze the resonant attenuation of the fissile material to the 10-1-102 eV photoneutrons emitted from and thermalized by the D2O photonto-neutron convertor, which converts X-rays to photoneutrons. Eight high-Z simulants are tested to confirm the feasibility of identifying the isotopes from the photoneutron resonance. The underlying principles and experimental results are discussed.

  6. SU-F-J-74: High Z Geometric Integrity and Beam Hardening Artifact Assessment Using a Retrospective Metal Artifact Reduction (MAR) Reconstruction Algorithm

    International Nuclear Information System (INIS)

    Woods, K; DiCostanzo, D; Gupta, N

    2016-01-01

    Purpose: To test the efficacy of a retrospective metal artifact reduction (MAR) reconstruction algorithm for a commercial computed tomography (CT) scanner for radiation therapy purposes. Methods: High Z geometric integrity and artifact reduction analysis was performed with three phantoms using General Electric’s (GE) Discovery CT. The three phantoms included: a Computerized Imaging Reference Systems (CIRS) electron density phantom (Model 062) with a 6.5 mm diameter titanium rod insert, a custom spine phantom using Synthes Spine hardware submerged in water, and a dental phantom with various high Z fillings submerged in water. Each phantom was reconstructed using MAR and compared against the original scan. Furthermore, each scenario was tested using standard and extended Hounsfield Unit (HU) ranges. High Z geometric integrity was performed using the CIRS phantom, while the artifact reduction was performed using all three phantoms. Results: Geometric integrity of the 6.5 mm diameter rod was slightly overestimated for non-MAR scans for both standard and extended HU. With MAR reconstruction, the rod was underestimated for both standard and extended HU. For artifact reduction, the mean and standard deviation was compared in a volume of interest (VOI) in the surrounding material (water and water equivalent material, ∼0HU). Overall, the mean value of the VOI was closer to 0 HU for the MAR reconstruction compared to the non-MAR scan for most phantoms. Additionally, the standard deviations for all phantoms were greatly reduced using MAR reconstruction. Conclusion: GE’s MAR reconstruction algorithm improves image quality with the presence of high Z material with minimal degradation of its geometric integrity. High Z delineation can be carried out with proper contouring techniques. The effects of beam hardening artifacts are greatly reduced with MAR reconstruction. Tissue corrections due to these artifacts can be eliminated for simple high Z geometries and greatly

  7. SU-F-J-74: High Z Geometric Integrity and Beam Hardening Artifact Assessment Using a Retrospective Metal Artifact Reduction (MAR) Reconstruction Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Woods, K; DiCostanzo, D; Gupta, N [Ohio State University Columbus, OH (United States)

    2016-06-15

    Purpose: To test the efficacy of a retrospective metal artifact reduction (MAR) reconstruction algorithm for a commercial computed tomography (CT) scanner for radiation therapy purposes. Methods: High Z geometric integrity and artifact reduction analysis was performed with three phantoms using General Electric’s (GE) Discovery CT. The three phantoms included: a Computerized Imaging Reference Systems (CIRS) electron density phantom (Model 062) with a 6.5 mm diameter titanium rod insert, a custom spine phantom using Synthes Spine hardware submerged in water, and a dental phantom with various high Z fillings submerged in water. Each phantom was reconstructed using MAR and compared against the original scan. Furthermore, each scenario was tested using standard and extended Hounsfield Unit (HU) ranges. High Z geometric integrity was performed using the CIRS phantom, while the artifact reduction was performed using all three phantoms. Results: Geometric integrity of the 6.5 mm diameter rod was slightly overestimated for non-MAR scans for both standard and extended HU. With MAR reconstruction, the rod was underestimated for both standard and extended HU. For artifact reduction, the mean and standard deviation was compared in a volume of interest (VOI) in the surrounding material (water and water equivalent material, ∼0HU). Overall, the mean value of the VOI was closer to 0 HU for the MAR reconstruction compared to the non-MAR scan for most phantoms. Additionally, the standard deviations for all phantoms were greatly reduced using MAR reconstruction. Conclusion: GE’s MAR reconstruction algorithm improves image quality with the presence of high Z material with minimal degradation of its geometric integrity. High Z delineation can be carried out with proper contouring techniques. The effects of beam hardening artifacts are greatly reduced with MAR reconstruction. Tissue corrections due to these artifacts can be eliminated for simple high Z geometries and greatly

  8. TU-H-CAMPUS-TeP1-03: Magnetically Focused Proton Irradiation of Small Volume Radiosurgery Targets

    Energy Technology Data Exchange (ETDEWEB)

    McAuley, GA; Slater, JM [Loma Linda University, Loma Linda, CA (United States); Wroe, AJ [Loma Linda University, Loma Linda, CA (United States); Loma Linda University Medical Center, Loma Linda, CA (United States)

    2016-06-15

    Purpose: To investigate the use of magnetic focusing for small volume proton radiosurgery targets using a triplet combination of quadrupole rare earth permanent magnet Halbach cylinder assemblies Methods: Fourteen quadrupole magnets consisting of 24 segments of radiation hard samarium-cobalt adhered into k=3 Halbach cylinders with various field gradients (100 to 250 T/m) were designed and manufactured. Triplet combinations of the magnets were placed on a positioning track on our Gantry 1 treatment table. Unmodulated 127 MeV proton beams with initial diameters of 3 to 20 mm were delivered to a water tank using single-stage scattering. Depth and transverse dose distributions were measured using a PTW PR60020 diode detector and EBT3 film, respectively. This data was compared with unfocused passively collimated beams. Monte Carlo simulations were also performed - both for comparison with experimental data and to further investigate the potential of triplet magnetic focusing. Results: Experimental results using 150 T/m gradient magnets and 15 to 20 mm initial diameter beams show peak to entrance dose ratios that are ∼ 43 to 48 % larger compared with spot size matched 8 mm collimated beams (ie, transverse profile full-widths at 90% maximum dose match within 0.5 mm of focused beams). In addition, the focusing beams were ∼ 3 to 4.4 times more efficient per MU in dose to target delivery. Additional results using different magnet combinations will also be presented. Conclusion: Our results suggest that triplet magnetic focusing could reduce entrance dose and beam number while delivering dose to small (∼≤ 10 mm diameter) radiosurgery targets in less time compared to unfocused beams. Immediate clinical applications include those associated with proton radiosurgery and functional radiosurgery of the brain and spine, however other treatment sites can be also envisioned. This project was sponsored with funding from the Department of Defense (DOD# W81XWH-BAA-10-1).

  9. Spallation Neutron Spectrum on a Massive Lead/Paraffin Target Irradiated with 1 GeV Protons

    CERN Document Server

    Adam, J; Barashenkov, V S; Brandt, R; Golovatiouk, V M; Kalinnikov, V G; Katovsky, K; Krivopustov, M I; Kumar, V; Kumawat, H; Odoj, R; Pronskikh, V S; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Westmeier, W

    2004-01-01

    The spectra of gamma-ray emitted by decaying residual nuclei, produced by spallation neutrons with (n, xn), (n,xnyp), (n,p), (n,gamma) reactions in activation threshold detectors - namely, ^{209}Bi, ^{197}Au, ^{59}Co, ^{115}In, ^{232}Th, were measured in the Laboratory of Nuclear Problems (LNP), JINR, Dubna, Russia. Spallation neutrons were generated by bombarding a 20 cm long cylindrical lead target, 8 cm in diameter, surrounded by a 6 cm thick layer of paraffin moderator, with a 1 GeV proton beam from the Nuclotron accelerator. Reaction rates and spallation neutron spectrum were measured and compared with CASCADE code calculations.

  10. Monte Carlo simulations and experimental results on neutron production in the spallation target QUINTA irradiated with 660 MeV protons

    International Nuclear Information System (INIS)

    Khushvaktov, J.H.; Yuldashev, B.S.; Adam, J.; Vrzalova, J.; Baldin, A.A.; Furman, W.I.; Gustov, S.A.; Kish, Yu.V.; Solnyshkin, A.A.; Stegailov, V.I.; Tichy, P.; Tsoupko-Sitnikov, V.M.; Tyutyunnikov, S.I.; Zavorka, L.; Svoboda, J.; Zeman, M.; Vespalec, R.; Wagner, V.

    2017-01-01

    The activation experiment was performed using the accelerated beam of the Phasotron accelerator at the Joint Institute for Nuclear Research (JINR). The natural uranium spallation target QUINTA was irradiated with protons of energy 660 MeV. Monte Carlo simulations were performed using the FLUKA and Geant4 codes. The number of leakage neutrons from the sections of the uranium target surrounded by the lead shielding and the number of leakage neutrons from the lead shield were determined. The total number of fissions in the setup QUINTA were determined. Experimental values of reaction rates for the produced nuclei in the "1"2"7I sample were obtained, and several values of the reaction rates were compared with the results of simulations by the FLUKA and Geant4 codes. The experimentally determined fluence of neutrons in the energy range of 10-200 MeV using the (n, xn) reactions in the "1"2"7I(NaI) sample was compared with the results of simulations. Possibility of transmutation of the long-lived radionuclide "1"2"9I in the QUINTA setup was estimated. [ru

  11. A molecular dynamics computer simulation of the time dependence of surface damage production in ion irradiated metal targets

    International Nuclear Information System (INIS)

    Webb, R.P.; Harrison, D.E.

    1984-01-01

    Molecular dynamics computer simulations have been used to study the development of ion-induced cascades in the surface region of an initially perfect single crystal metal target. A 16 mm movie has been produced to show the temporal progress of individual cascades. The cascades can then be seen to be formed from a few high energy primary knock-on initiated replacement collision sequences which overlap to form the more usual interpretation of a mature collision cascade. However, it is before the collision cascade has matured, and while the replacement sequences are spreading, that the majority of atoms (> 80%) are ejected. These qualitative observations are also upheld more quantatively in a global average, over many cascades, of the ejection time of each atom. This gives rise to the appearance of a statistical ejection front which propagates radially outwards, from the impact point on the crystal surface, with a well defined velocity. (author)

  12. Target for production of X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Korenev, S.A. E-mail: sergey_korenev@steris.com

    2004-10-01

    The patented new type of X-ray target is considered in this report. The main concept of the target consists in developing a sandwich structure depositing a coating of materials with high Z on the substrate with low Z, high thermal conductivity and high thermal stability. The target presents multiple layers system. The thermal conditions for X-ray target are discussed. The experimental results for Ta target on the Al and Cu substrates are presented.

  13. Target for production of X-rays

    International Nuclear Information System (INIS)

    Korenev, S.A.

    2004-01-01

    The patented new type of X-ray target is considered in this report. The main concept of the target consists in developing a sandwich structure depositing a coating of materials with high Z on the substrate with low Z, high thermal conductivity and high thermal stability. The target presents multiple layers system. The thermal conditions for X-ray target are discussed. The experimental results for Ta target on the Al and Cu substrates are presented

  14. Target for production of X-rays

    Science.gov (United States)

    Korenev, S. A.

    2004-09-01

    The patented new type of X-ray target is considered in this report. The main concept of the target consists in developing a sandwich structure depositing a coating of materials with high Z on the substrate with low Z, high thermal conductivity and high thermal stability. The target presents multiple layers system. The thermal conditions for X-ray target are discussed. The experimental results for Ta target on the Al and Cu substrates are presented.

  15. SU-F-T-645: To Test Spatial Anddosimetric Accuracy of Small Cranial Target Irradiation Based On 1.5 T MRIscans Using Static Arcs with MLCDefined Fields

    International Nuclear Information System (INIS)

    Brezovich, I; Wu, X; Popple, R; Shen, S; Cardan, R; Bolding, M; Fiveash, J; Kraus, J; Spencer, S

    2016-01-01

    Purpose: To test spatial and dosimetric accuracy of small cranial target irradiation based on 1.5 T MRI scans using static arcs with MLC-defined fields Methods: A plastic (PMMA) phantom simulating a small brain lesion was mounted on a GammaKnife headframe equipped with MRI localizer. The lesion was a 3 mm long, 3.175 mm diameter cylindrical cavity filled with MRI contrast. Radiochromic film passing through the cavity was marked with pin pricks at the cavity center. The cavity was contoured on an MRI image and fused with CT to simulate treatment of a lesion not visible on CT. The transfer of the target to CT involved registering the MRI contrast cannels of the localizer that were visible on both modalities. Treatments were planned to deliver 800 cGy to the cavity center using multiple static arcs with 5.0×2.4 mm MLC-defined fields. The phantom was aligned on a STx accelerator by registering the conebeam CT with the planning CT. Films from coronal and sagittal planes were scanned and evaluated using ImageJ software Results: Geographic errors in treatment based on 1.5 T scans agreed within 0.33, −0.27 and 1.21 mm in the vertical, lateral and longitudinal dimensions, respectively. The doses delivered to the cavity center were 7.2% higher than planned. The dose distributions were similar to those of a GammaKnife. Conclusion: Radiation can be delivered with an accelerator at mm accuracy to small cranial targets based on 1.5 MRI scans fused to CTs using a standard GammaKnife headframe and MRI localizer. MLC-defined static arcs produce isodose lines very similar to the GammaKnife.

  16. Modulation of the Rho/ROCK pathway in heart and lung after thorax irradiation reveals targets to improve normal tissue toxicity.

    Science.gov (United States)

    Monceau, Virginie; Pasinetti, Nadia; Schupp, Charlotte; Pouzoulet, Fred; Opolon, Paule; Vozenin, Marie-Catherine

    2010-11-01

    The medical options available to prevent or treat radiation-induced injury are scarce and developing effective countermeasures is still an open research field. In addition, more than half of cancer patients are treated with radiation therapy, which displays a high antitumor efficacy but can cause, albeit rarely, disabling long-term toxicities including radiation fibrosis. Progress has been made in the definition of molecular pathways associated with normal tissue toxicity that suggest potentially effective therapeutic targets. Targeting the Rho/ROCK pathway seems a promising anti-fibrotic approach, at least in the gut; the current study was performed to assess whether this target was relevant to the prevention and/or treatment of injury to the main thoracic organs, namely heart and lungs. First, we showed activation of two important fibrogenic pathways (Smad and Rho/ROCK) in response to radiation-exposure to adult cardiomyocytes; we extended these observations in vivo to the heart and lungs of mice, 15 and 30 weeks post-irradiation. We correlated this fibrogenic molecular imprint with alteration of heart physiology and long-term remodelling of pulmonary and cardiac histological structures. Lastly, cardiac and pulmonary radiation injury and bleomycin-induced pulmonary fibrosis were successfully modulated using Rho/ROCK inhibitors (statins and Y-27632) and this was associated with a normalization of fibrogenic markers. In conclusion, the present paper shows for the first time, activation of Rho/ROCK and Smad pathways in pulmonary and cardiac radiation-induced delayed injury. Our findings thereby reveal a safe and efficient therapeutic opportunity for the abrogation of late thoracic radiation injury, potentially usable either before or after radiation exposure; this approach is especially attractive in (1) the radiation oncology setting, as it does not interfere with prior anti-cancer treatment and in (2) radioprotection, as applicable to the treatment of established

  17. Modulation of the ρ/rock pathway in heart and lung after thorax irradiation reveals targets to improve normal tissue toxicity

    International Nuclear Information System (INIS)

    Monceau, V.; Pasinetti, N.; Schupp, C.; Pouzoulet, F.; Opolon, P.; Vozenin, M.C.

    2010-01-01

    The medical options available to prevent or treat radiation-induced injury are scarce and developing effective countermeasures is still an open research field. In addition, more than half of cancer patients are treated with radiation therapy, which displays a high antitumor efficacy but can cause, albeit rarely, disabling long-term toxicities including radiation fibrosis. Progress has been made in the definition of molecular pathways associated with normal tissue toxicity that suggest potentially effective therapeutic targets. Targeting the Rho/ROCK pathway seems a promising anti-fibrotic approach, at least in the gut; the current study was performed to assess whether this target was relevant to the prevention and/or treatment of injury to the main thoracic organs, namely heart and lungs. First, we showed activation of two important fibro-genic pathways (Smad and Rho/ROCK) in response to radiation-exposure to adult cardio-myocytes; we extended these observations in vivo to the heart and lungs of mice, 15 and 30 weeks post-irradiation. We correlated this fibro-genic molecular imprint with alteration of heart physiology and long-term remodelling of pulmonary and cardiac histological structures. Lastly, cardiac and pulmonary radiation injury and bleomycin-induced pulmonary fibrosis were successfully modulated using Rho/ROCK inhibitors (statins and Y-27632) and this was associated with a normalization of fibro-genic markers. In conclusion, the present paper shows for the first time, activation of Rho/ROCK and Smad pathways in pulmonary and cardiac radiation-induced delayed injury. Our findings thereby reveal a safe and efficient therapeutic opportunity for the abrogation of late thoracic radiation injury, potentially usable either before or after radiation exposure; this approach is especially attractive in (1) the radiation oncology setting, as it does not interfere with prior anti-cancer treatment and in (2) radioprotection, as applicable to the treatment of

  18. Radiosensitization of high-Z compounds by medium-energy 160 kV vs. high-energy 6 MV X-rays for radiation therapy: Theoretical, in vitro and in vivo studies of platinum compounds activating glioma F98 cancer cells

    Science.gov (United States)

    Lim, S.; Pradhan, A.; Nahar, S.; Montenegro, M.; Barth, R.; Nakkula, R.; Turro, C.

    2013-03-01

    Energy dependence of X-ray irradiation of high-Z compounds for enhanced radiosensitization is explored thoeretically and via in vitro and in vivo experiments. The cell killing ability of medium-energy X-rays from 160 kV source are found to be more effective than 6 MV X-rays in activating high-Z contrast agents. Results are presented for a newly synthesized Pt compound, Pyridine Terpyridine Pt(II) Nitrate ([Pt(typ)(py)]) and carboplatin in treating F98 rat glioma. In-vitro results show considerable reduction in cell viability for radiosensitized cells irradiated with a 160 kV irradiator. Cells treated with 6 MV LINAC radiation find little variation with radiation dose. Maximum dose enhancement factors (DEFs) and minimum cancer cell survival fractions correspond to 50-200 keV range, and fall rapidly at higher energies. Theoretical calculations of photoelectric absorption vis-a-vis total scattering demonstrates this energy dependence. However, in vivo studies of rats treated with [Pt(tpy)(py)] had a severe negative neurotoxic response, confirmed by histopathological analysis. But subsequent in vivo studies using carboplatin showed very positive results in the treatment of F98 glioma bearing rats and potential clinical radiation therapy.

  19. Mapping of nodal disease in locally advanced prostate cancer: Rethinking the clinical target volume for pelvic nodal irradiation based on vascular rather than bony anatomy

    International Nuclear Information System (INIS)

    Shih, Helen A.; Harisinghani, Mukesh; Zietman, Anthony L.; Wolfgang, John A.; Saksena, Mansi; Weissleder, Ralph

    2005-01-01

    Purpose: Toxicity from pelvic irradiation could be reduced if fields were limited to likely areas of nodal involvement rather than using the standard 'four-field box.' We employed a novel magnetic resonance lymphangiographic technique to highlight the likely sites of occult nodal metastasis from prostate cancer. Methods and Materials: Eighteen prostate cancer patients with pathologically confirmed node-positive disease had a total of 69 pathologic nodes identifiable by lymphotropic nanoparticle-enhanced MRI and semiquantitative nodal analysis. Fourteen of these nodes were in the para-aortic region, and 55 were in the pelvis. The position of each of these malignant nodes was mapped to a common template based on its relation to skeletal or vascular anatomy. Results: Relative to skeletal anatomy, nodes covered a diffuse volume from the mid lumbar spine to the superior pubic ramus and along the sacrum and pelvic side walls. In contrast, the nodal metastases mapped much more tightly relative to the large pelvic vessels. A proposed pelvic clinical target volume to encompass the region at greatest risk of containing occult nodal metastases would include a 2.0-cm radial expansion volume around the distal common iliac and proximal external and internal iliac vessels that would encompass 94.5% of the pelvic nodes at risk as defined by our node-positive prostate cancer patient cohort. Conclusions: Nodal metastases from prostate cancer are largely localized along the major pelvic vasculature. Defining nodal radiation treatment portals based on vascular rather than bony anatomy may allow for a significant decrease in normal pelvic tissue irradiation and its associated toxicities

  20. Human cytotoxic T-lymphocyte membrane-camouflaged nanoparticles combined with low-dose irradiation: a new approach to enhance drug targeting in gastric cancer

    Directory of Open Access Journals (Sweden)

    Zhang L

    2017-03-01

    Full Text Available Lianru Zhang, Rutian Li, Hong Chen, Jia Wei, Hanqing Qian, Shu Su, Jie Shao, Lifeng Wang, Xiaoping Qian, Baorui Liu The Comprehensive Cancer Centre of Drum Tower Hospital, Medical School of Nanjing University and Clinical Cancer Institute of Nanjing University, Nanjing, People’s Republic of China Abstract: Cell membrane-derived nanoparticles are becoming more attractive because of their ability to mimic many features of their source cells. This study reports on a biomimetic delivery platform based on human cytotoxic T-lymphocyte membranes. In this system, the surface of poly-lactic-co-glycolic acid nanoparticles was camouflaged using T-lymphocyte membranes, and local low-dose irradiation (LDI was used as a chemoattractant for nanoparticle targeting. The T-lymphocyte membrane coating was verified using dynamic light scattering, transmission electron microscopy, and confocal laser scanning microscopy. This new platform reduced nanoparticle phagocytosis by macrophages to 23.99% (P=0.002. Systemic administration of paclitaxel-loaded T-lymphocyte membrane-coated nanoparticles inhibited the growth of human gastric cancer by 56.68% in Balb/c nude mice. Application of LDI at the tumor site significantly increased the tumor growth inhibition rate to 88.50%, and two mice achieved complete remission. Furthermore, LDI could upregulate the expression of adhesion molecules in tumor vessels, which is important in the process of leukocyte adhesion and might contribute to the localization of T-lymphocyte membrane-encapsulated nanoparticles in tumors. Therefore, this new drug-delivery platform retained both the long circulation time and tumor site accumulation ability of human cytotoxic T lymphocytes, while local LDI could significantly enhance tumor localization. Keywords: cell membrane, drug delivery system, gastric cancer, low-dose irradiation, nanoparticles

  1. Fiscal year 1976T (add-on quarter) DT fusion neutron irradiations and dosimetry at the LLL rotating target neutron source

    International Nuclear Information System (INIS)

    MacLean, S.C.

    1977-01-01

    The DT fusion neutron irradiation of more than 90 samples during seven irradiation periods (beam-on time of more than 430.9 hours) is described. Experiments from 15 individuals representing six institutions are summarized. The numbers of UCID dosimetry reports detailing each of the irradiations is given

  2. Production and separation of no-carrier-added 73As and 75Se from 7Li irradiated germanium oxide target

    International Nuclear Information System (INIS)

    Mandal, A.; Lahiri, S.

    2012-01-01

    This work reports for the first time 7 Li-induced accelerator based production of 71,72,73,74 As, 75,76,77 Br and 73,75 Se radionuclides in their no-carrier-added (nca) state. After the decay of all short-lived radionuclides 75 Se and 73 As were only existing radionuclides in germanium oxide target, which were subsequently separated by liquid-liquid extraction (LLX) using trioctylamine (TOA) dissolved in cyclohexane as liquid ion exchanger. The presence of stable germanium in various fractions was examined by Inductively Coupled Plasma Optical Spectrometry (ICP-OES). At 0.1 M TOA and 10 M HCl concentration, 75 Se and stable Ge were extracted into the organic phase leaving 73 As in the aqueous phase. The bulk Ge was stripped back to the aqueous phase by 1 M NaOH, keeping 75 Se in the organic phase. Therefore complete separation between 73 As, 75 Se and bulk Ge was achieved. (orig.)

  3. Application of on-line HPLC-ICP-MS for the determination of the nuclide abundances of lanthanides produced via spallation reactions in an irradiated tantalum target of a spallation neutron source

    International Nuclear Information System (INIS)

    Kerl, W.; Becker, J.S.; Dietze, H.J.

    1998-01-01

    An analytical procedure has been developed for the determination of spallation nuclides in an irradiated tantalum target using HPLC coupled on-line to ICP-MS after dissolution and separation of the tantalum matrix. Pieces of tantalum were taken from different locations of the irradiated tantalum target which had been used as the target material in a spallation neutron source. Tantalum was dissolved in a HNO 3 /HF mixture and the tantalum matrix was separated by liquid-liquid extraction so that only the spallation nuclides were left in the sample solutions. The major fraction of the spallation nuclides in the tantalum target are lanthanide metals in the μg g -1 concentration range determined in the present study. Additional reaction products are formed by the irradiation of trace impurities in the original tantalum target. The nuclide abundances of the lanthanide metals measured in the tantalum target differ significantly from the natural isotopic composition so that a lot of isobaric interferences of long-lived radionuclides and stable isotopes in the mass spectrum are to be expected. Therefore, all the lanthanide metals had to be separated chemically prior to their mass spectrometric determination. The separation of all rare earth elements was performed by ion chromatography on-line to ICP-MS. The nuclide abundances of each lanthanide were determined using a sensitive double-focusing sector field inductively coupled plasma mass spectrometer. The nuclide abundances of the lanthanides in the irradiated tantalum target calculated theoretically and the experimental results obtained by on-line HPLC-ICP-MS proved to be in good agreement. (orig.)

  4. Parallel transport studies of high-Z impurities in the core of Alcator C-Mod plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Reinke, M. L.; Hutchinson, I. H.; Rice, J. E.; Greenwald, M.; Howard, N. T.; Hubbard, A.; Hughes, J. W.; Terry, J. L.; Wolfe, S. M. [MIT-Plasma Science and Fusion Center Cambridge, Massachusetts 02139 (United States)

    2013-05-15

    Measurements of poloidal variation, ñ{sub z}/, in high-Z impurity density have been made using photodiode arrays sensitive to vacuum ultraviolet and soft x-ray emission in Alcator C-Mod plasmas. In/out asymmetries in the range of −0.2<0.3 are observed for r/a<0.8, and accumulation on both the high-field side, n{sub z,cos}<0, and low-field side, n{sub z,cos}>0, of a flux surface is found to be well described by a combination of centrifugal, poloidal electric field, and ion-impurity friction effects. Up/down asymmetries, −0.05<0.10, are observed over 0.50 corresponding to accumulation opposite the ion ∇B drift direction. Measurements of the up/down asymmetry of molybdenum are found to disagree with predictions from recent neoclassical theory in the trace limit, n{sub z}Z{sup 2}/n{sub i}≪1. Non-trace levels of impurities are expected to modify the main-ion poloidal flow and thus change friction-driven impurity density asymmetries and impurity poloidal rotation, v{sub θ,z}. Artificially modifying main-ion flow in parallel transport simulations is shown to impact both ñ{sub z}/ and v{sub θ,z}, but simultaneous agreement between measured and predicted up/down and in/out asymmetry as well as impurity poloidal rotation is not possible for these C-Mod data. This link between poloidal flow and poloidal impurity density variation outlines a more stringent test for parallel neoclassical transport theory than has previously been performed. Measurement and computational techniques specific to the study of poloidal impurity asymmetry physics are discussed as well.

  5. Ionization Processes in the Atmosphere of Titan (Research Note). III. Ionization by High-Z Nuclei Cosmic Rays

    Science.gov (United States)

    Gronoff, G.; Mertens, C.; Lilensten, J.; Desorgher, L.; Fluckiger, E.; Velinov, P.

    2011-01-01

    Context. The Cassini-Huygens mission has revealed the importance of particle precipitation in the atmosphere of Titan thanks to in-situ measurements. These ionizing particles (electrons, protons, and cosmic rays) have a strong impact on the chemistry, hence must be modeled. Aims. We revisit our computation of ionization in the atmosphere of Titan by cosmic rays. The high-energy high-mass ions are taken into account to improve the precision of the calculation of the ion production profile. Methods. The Badhwahr and O Neill model for cosmic ray spectrum was adapted for the Titan model. We used the TransTitan model coupled with the Planetocosmics model to compute the ion production by cosmic rays. We compared the results with the NAIRAS/HZETRN ionization model used for the first time for a body that differs from the Earth. Results. The cosmic ray ionization is computed for five groups of cosmic rays, depending on their charge and mass: protons, alpha, Z = 8 (oxygen), Z = 14 (silicon), and Z = 26 (iron) nucleus. Protons and alpha particles ionize mainly at 65 km altitude, while the higher mass nucleons ionize at higher altitudes. Nevertheless, the ionization at higher altitude is insufficient to obscure the impact of Saturn s magnetosphere protons at a 500 km altitude. The ionization rate at the peak (altitude: 65 km, for all the different conditions) lies between 30 and 40/cu cm/s. Conclusions. These new computations show for the first time the importance of high Z cosmic rays on the ionization of the Titan atmosphere. The updated full ionization profile shape does not differ significantly from that found in our previous calculations (Paper I: Gronoff et al. 2009, 506, 955) but undergoes a strong increase in intensity below an altitude of 400 km, especially between 200 and 400 km altitude where alpha and heavier particles (in the cosmic ray spectrum) are responsible for 40% of the ionization. The comparison of several models of ionization and cosmic ray spectra (in

  6. The Extremely Luminous Quasar Survey (ELQS) in SDSS and the high-z bright-end Quasar Luminosity Function

    Science.gov (United States)

    Schindler, Jan-Torge; Fan, Xiaohui; McGreer, Ian

    2018-01-01

    Studies of the most luminous quasars at high redshift directly probe the evolution of the most massive black holes in the early Universe and their connection to massive galaxy formation. Unfortunately, extremely luminous quasars at high redshift are very rare objects. Only wide area surveys have a chance to constrain their population. The Sloan Digital Sky Survey (SDSS) nd the Baryon Oscillation Spectroscopic Survey (BOSS) have so far provided the most widely adopted measurements of the type I quasar luminosity function (QLF) at z>3. However, a careful re-examination of the SDSS quasar sample revealed that the SDSS quasar selection is in fact missing a significant fraction of $z~3$ quasars at the brightest end.We have identified the purely optical color selection of SDSS, where quasars at these redshifts are strongly contaminated by late-type dwarfs, and the spectroscopic incompleteness of the SDSS footprint as the main reasons. Therefore we have designed the Extremely Luminous Quasar Survey (ELQS), based on a novel near-infrared JKW2 color cut using WISE AllWISE and 2MASS all-sky photometry, to yield high completeness for very bright (i < 18.0) quasars in the redshift range of 2.8<= z<=5.0. It effectively uses Random Forest machine-learning algorithms on SDSS and WISE photometry for quasar-star classification and photometric redshift estimation.The ELQS is spectroscopically following up ~230 new quasar candidates in an area of ~12000 deg2 in the SDSS footprint, to obtain a well-defined and complete quasar sample for an accurate measurement of the bright-end quasar luminosity function (QLF) at 2.8<= z<=5.0. So far the ELQS has identified 75 bright new quasars in this redshift range and observations of the fall sky will continue until the end of the year. At the AAS winter meeting we will present the full spectroscopic results of the survey, including a re-estimation and extension of the high-z QLF toward higher luminosities.

  7. Clinical target volume localization using conventional methods (anatomy and palpation) and ultrasonography in early breast cancer post-operative external irradiation

    International Nuclear Information System (INIS)

    Valdagni, Riccardo; Italia, Corrado; Montanaro, Paolo; Ciocca, Mario; Morandi, Giovanni; Salvadori, Bruno

    1997-01-01

    Purpose: To evaluate the accuracy of three methods, anatomy (A), palpation (P) and ultrasounds (US) in localizing the clinical target volume (CTV) in patients (pts) with early breast cancer (EBC) undergoing breast external irradiation as part of conservation therapy. Material and methods: One hundred consecutive pts with EBC (T is 1%, T 1 78%, T 2 21%, N- 68%, N+ 32%), treated with conservation surgery and breast irradiation with opposed tangential portals, were prospectively analyzed. Anatomically, palpatory or ultrasound defined field borders for CTV localizations were determined in the same position thanks to the utilization of a vacuum-formed cellulose acetate immobilization cast, removed during CTV definitions. Results: P and US CTV localizations have been found to coincide on the four margins (superior, inferior, medial, lateral) in only(1(100)) pts, while no pt showed identical A and US CTV localizations. Only (31(397)) (8%) field measurements with A, and(98(395)) (25%) with P corresponded to US border definition. If mean and median values of each field border were considered, the CTV was generally over-estimated with P appearing more accurate than A in a gross definition of the target (P < 0.01). However, a geographical miss of at least one field border of CTV occurred in 55% of pts with A and in 36% of pts with P. The most critical margin to be defined with conventional methods was the superior one: an underestimation of the cranial border of CTV with A was observed in 51% and with P in 22% of pts (22% and 8%, respectively, when an underestimation by more than 1.5 cm was considered). When pre-menopausal and peri/post-menopausal groups of pts were separately analyzed, conventional methods were highly inaccurate to define the superior border in younger pts, in which a geographical miss was noted with A in 62% and with P in 35% of cases (P < 0.05). When an underestimation of more than 1.5 cm was evaluated, these values were reduced to 33% and 12

  8. Cardiac and pulmonary dose reduction for tangentially irradiated breast cancer, utilizing deep inspiration breath-hold with audio-visual guidance, without compromising target coverage

    International Nuclear Information System (INIS)

    Vikstroem, Johan; Hjelstuen, Mari H.B.; Mjaaland, Ingvil; Dybvik, Kjell Ivar

    2011-01-01

    Background and purpose. Cardiac disease and pulmonary complications are documented risk factors in tangential breast irradiation. Respiratory gating radiotherapy provides a possibility to substantially reduce cardiopulmonary doses. This CT planning study quantifies the reduction of radiation doses to the heart and lung, using deep inspiration breath-hold (DIBH). Patients and methods. Seventeen patients with early breast cancer, referred for adjuvant radiotherapy, were included. For each patient two CT scans were acquired; the first during free breathing (FB) and the second during DIBH. The scans were monitored by the Varian RPM respiratory gating system. Audio coaching and visual feedback (audio-visual guidance) were used. The treatment planning of the two CT studies was performed with conformal tangential fields, focusing on good coverage (V95>98%) of the planning target volume (PTV). Dose-volume histograms were calculated and compared. Doses to the heart, left anterior descending (LAD) coronary artery, ipsilateral lung and the contralateral breast were assessed. Results. Compared to FB, the DIBH-plans obtained lower cardiac and pulmonary doses, with equal coverage of PTV. The average mean heart dose was reduced from 3.7 to 1.7 Gy and the number of patients with >5% heart volume receiving 25 Gy or more was reduced from four to one of the 17 patients. With DIBH the heart was completely out of the beam portals for ten patients, with FB this could not be achieved for any of the 17 patients. The average mean dose to the LAD coronary artery was reduced from 18.1 to 6.4 Gy. The average ipsilateral lung volume receiving more than 20 Gy was reduced from 12.2 to 10.0%. Conclusion. Respiratory gating with DIBH, utilizing audio-visual guidance, reduces cardiac and pulmonary doses for tangentially treated left sided breast cancer patients without compromising the target coverage

  9. Cardiac and pulmonary dose reduction for tangentially irradiated breast cancer, utilizing deep inspiration breath-hold with audio-visual guidance, without compromising target coverage

    Energy Technology Data Exchange (ETDEWEB)

    Vikstroem, Johan; Hjelstuen, Mari H.B.; Mjaaland, Ingvil; Dybvik, Kjell Ivar (Dept. of Radiotherapy, Stavanger Univ. Hospital, Stavanger (Norway)), e-mail: vijo@sus.no

    2011-01-15

    Background and purpose. Cardiac disease and pulmonary complications are documented risk factors in tangential breast irradiation. Respiratory gating radiotherapy provides a possibility to substantially reduce cardiopulmonary doses. This CT planning study quantifies the reduction of radiation doses to the heart and lung, using deep inspiration breath-hold (DIBH). Patients and methods. Seventeen patients with early breast cancer, referred for adjuvant radiotherapy, were included. For each patient two CT scans were acquired; the first during free breathing (FB) and the second during DIBH. The scans were monitored by the Varian RPM respiratory gating system. Audio coaching and visual feedback (audio-visual guidance) were used. The treatment planning of the two CT studies was performed with conformal tangential fields, focusing on good coverage (V95>98%) of the planning target volume (PTV). Dose-volume histograms were calculated and compared. Doses to the heart, left anterior descending (LAD) coronary artery, ipsilateral lung and the contralateral breast were assessed. Results. Compared to FB, the DIBH-plans obtained lower cardiac and pulmonary doses, with equal coverage of PTV. The average mean heart dose was reduced from 3.7 to 1.7 Gy and the number of patients with >5% heart volume receiving 25 Gy or more was reduced from four to one of the 17 patients. With DIBH the heart was completely out of the beam portals for ten patients, with FB this could not be achieved for any of the 17 patients. The average mean dose to the LAD coronary artery was reduced from 18.1 to 6.4 Gy. The average ipsilateral lung volume receiving more than 20 Gy was reduced from 12.2 to 10.0%. Conclusion. Respiratory gating with DIBH, utilizing audio-visual guidance, reduces cardiac and pulmonary doses for tangentially treated left sided breast cancer patients without compromising the target coverage

  10. Postirradiation evaluations of capsules HANS-1 and HANS-2 irradiated in the HFIR target region in support of fuel development for the advanced neutron source

    International Nuclear Information System (INIS)

    Hofman, G.L.; Snelgrove, J.L.; Copeland, G.L.

    1995-08-01

    This report describes the design, fabrication, irradiation, and evaluation of two capsule tests containing U 3 Si 2 fuel particles in contact with aluminum. The tests were in support of fuel qualification for the Advanced Neutron Source (ANS) reactor, a high-powered research reactor that was planned for the Oak Ridge National Laboratory. At the time of these tests, the fuel consisted of U 3 Si 2 , containing highly enriched uranium dispersed in aluminum at a volume fraction of ∼0.15. The extremely high thermal flux in the target region of the High Flux Isotope Reactor provided up to 90% burnup in one 23-d cycle. Temperatures up to 450 degrees C were maintained by gamma heating. Passive SiC temperature monitors were employed. The very small specimen size allowed only microstructural examination of the fuel particles but also allowed many specimens to be tested at a range of temperatures. The determination of fission gas bubble morphology by microstructural examination has been beneficial in developing a fuel performance model that allows prediction of fuel performance under these extreme conditions. The results indicate that performance of the reference fuel would be satisfactory under the ANS conditions. In addition to U 3 Si 2 , particles of U 3 Si, UAl 2 , UAl x , and U 3 O 8 were tested

  11. Experimental and theoretical study of the residual nuclide production in 40-2600 MeV proton-irradiated thin targets of ads structure materials

    International Nuclear Information System (INIS)

    Titarenko, Yu.E.; Batyaev, V.F.; Belonozhenko, A.A.; Borovlev, S.P.; Butko, M.A.; Florya, S.N.; Pavlov, K.V.; Rogov, V.I.; Tikhonov, R.S.; Titarenko, A.Yu.; Zhivun, V.M.

    2011-10-01

    The Project is aimed at experimental and theoretical studying the independent and cumulative yields of residual radioactive nuclei produced in high-energy proton-irradiated structure materials intended for constructing the high-power Accelerator-Driven Systems (ADS) with a high-current proton accelerator. The Project is an extension of the researches carried out earlier under the ISTC Projects #017, #839, and #2002 which provided more 10000 residual nuclide production cross sections mainly in materials intended to use as target materials of the ADS. This Project includes 57 measurement runs carried out using the 97 targets made only of the ADS structural materials of both monoisotopic ( 56 Fe, 93 Nb, 181 Ta) and natural ( nat Cr, nat Ni, nat W) compositions within minutely fractionated proton energy range, namely, at 0.04, 0.07, 0.1, 0.15, 0.25, 0.4, 0.6, 0.8, 1.2, 1.6 and 2.6GeV. All the targets were irradiated using the ITEP U-10 proton synchrotron. The experimental nuclide yields are determined by the direct γ-spectrometry and α-spectrometry methods. As a result, 3839 cumulative and independent yields of residual β-radioactive product nuclei with lifetimes range from 6 minutes to 10 years as well as 12 cumulative yields of α- radioactive 148 Gd whose lifetime is 74.6 years have been measured. Besides, the cross sections for the 27 Al(p,x) 22 Na , 27 Al(p,x) 24 Na and 27 Al(p,x) 7 Be monitor reactions have been measured at the same proton energies with the use of the current transformer technique. The γ-spectrometer resolution is 1.8 keV in the 1332 keV 60 Co γ-line. The experimental γ-spectra were processed by the GENIE2000 code. The γ-lines were identified, and the cross sections calculated, by the ITEP-developed SIGMA code using the PCNUDAT database. The proton fluence was monitored by the 27 Al(p,x) 22 Na reaction. Measurement data have been compared with the calculation results of the BERTINI and ISABEL models of MCNPX code, CEM03.02, INCL 4.2, INCL4

  12. WE-G-BRE-09: Targeted Radiotherapy Enhancement During Accelerated Partial Breast Irradiation (ABPI) Using Controlled Release of Gold Nanoparticles (GNPs)

    International Nuclear Information System (INIS)

    Cifter, G; Ngwa, W; Chin, J; Cifter, F; Sajo, E; Sinha, N; Bellon, J

    2014-01-01

    Purpose: Several studies have demonstrated low rates of local recurrence with brachytherapy-based accelerated partial breast irradiation (APBI). However, long-term outcomes on toxicity (e.g. telangiectasia), and cosmesis remain a major concern. The purpose of this study is to investigate the dosimetric feasibility of using targeted non-toxic radiosensitizing gold nanoparticles (GNPs) for localized dose enhancement to the planning target volume (PTV) during APBI while reducing dose to normal tissue. Methods: Two approaches for administering the GNPs were considered. In one approach, GNPs are assumed to be incorporated in a micrometer-thick polymer film on the surface of routinely used mammosite balloon applicators, for sustained controlled in-situ release, and subsequent treatment using 50-kVp Xoft devices. In case two, GNPs are administered directly into the lumpectomy cavity e.g. via injection or using fiducials coated with the GNP-loaded polymer film. Recent studies have validated the use of fiducials for reducing the PTV margin during APBI with 6 MV beams. An experimentally determined diffusion coefficient was used to determine space-time customizable distribution of GNPs for feasible in-vivo concentrations of 43 mg/g. An analytic calculational approach from previously published work was employed to estimate the dose enhancement due to GNPs (2 and 10 nm) as a function of distance up to 1 cm from lumpectomy cavity. Results: Dose enhancement due to GNP was found to be about 130% for 50-kVp x-rays, and 110% for 6-MV external beam radiotherapy, 1 cm away from the lumpectomy cavity wall. Higher customizable dose enhancement could be achieved at other distances as a function of nanoparticle size. Conclusion: Our preliminary results suggest that significant dose enhancement can be achieved to residual tumor cells targeted with GNPs during APBI with electronic brachytherapy or external beam therapy. The findings provide a useful basis for developing nanoparticle

  13. Reducing the effects of X-ray pre-heat in double shell NIF capsules by over-coating the high Z shell

    Science.gov (United States)

    Wilson, Douglas; Milovich, J. L.; Daughton, W. S.; Loomis, E. N.; Sauppe, J. P.; Dodd, E. S.; Merritt, E. C.; Montgomery, D. S.; Renner, D. B.; Haines, B. M.; Cardenas, T.; Desjardins, T.; Palaniyappan, S.; Batha, S. H.

    2017-10-01

    Hohlraum generated X-rays will penetrate the ablator of a double shell capsule and be absorbed in the outer surface of the inner capsule. The ablative pressure this generates drives a shock into the central fuel, and a reflected shock that reaches the inner high-Z shell surface before the main shock even enters the fuel. With a beryllium over-coat preheat X-rays deposit just inside the beryllium/high z interface. The beryllium tamps the preheat expansion, eliminating ablation, and dramatically reducing pressure. The slow shock or pressure wave it generates is then overtaken by the main shock, avoiding an early shock in the fuel and increasing capsule yield.

  14. Niobium–niobium oxide multilayered coatings for corrosion protection of proton-irradiated liquid water targets for ["1"8F] production

    International Nuclear Information System (INIS)

    Skliarova, Hanna; Renzelli, Marco; Azzolini, Oscar; Felicis, Daniele de; Bemporad, Edoardo; Johnson, Richard R.; Palmieri, Vincenzo

    2015-01-01

    Chemically inert coatings on Havar"® entrance foils of the targets for ["1"8F] production via proton irradiation of enriched water at pressurized conditions are needed to decrease the amount of ionic contaminants released from Havar"®. During current investigation, magnetron sputtered niobium and niobium oxide were chosen as the candidates for protective coatings because of their superior chemical resistance. Aluminated quartz substrates allowed us to verify the protection efficiency of the desirable coatings as diffusion barriers. Two modeling corrosion tests based on the extreme susceptibility of aluminum to liquid gallium and acid corrosion were applied. As far as niobium coatings obtained by magnetron sputtering are columnar, the grain boundaries provide a fast diffusion path for active species of corrosive media to penetrate and to corrode the substrate. Amorphous niobium oxide films obtained by reactive magnetron sputtering showed superior barrier properties according to the corrosion tests performed. In order to prevent degrading of brittle niobium oxide at high pressures, multilayers combining high ductility of niobium with superior diffusion barrier efficiency of niobium oxide were proposed. The intercalation of niobium oxide interlayers was proved to interrupt the columnar grain growth of niobium during sputtering, resulting in improved diffusion barrier efficiency of obtained multilayers. The thin layer multilayer coating architecture with 70 nm bi-layer thickness was found preferential because of higher thermal stability. - Highlights: • Diffusion barrier efficiency of niobium, niobium oxide and their multilayers was studied. • The intercalation of niobium oxide layers interrupted the columnar grain growth of niobium. • The bilayer architectures influenced the stability of the multilayer coatings. • The thin layer multilayer coating with 70 nm double-layer was found superior.

  15. Niobium–niobium oxide multilayered coatings for corrosion protection of proton-irradiated liquid water targets for [{sup 18}F] production

    Energy Technology Data Exchange (ETDEWEB)

    Skliarova, Hanna, E-mail: Hanna.Skliarova@lnl.infn.it [National Institute of Nuclear Physics, Legnaro National Laboratories, Viale dell' Università, 2, 35020 Legnaro, Padua (Italy); University of Ferrara, Ferrara (Italy); Renzelli, Marco, E-mail: marco.renzelli@uniroma3.it [University of Rome “Roma TRE”, Via della Vasca Navale, 79, 00146 Rome (Italy); Azzolini, Oscar, E-mail: Oscar.Azzolini@lnl.infn.it [National Institute of Nuclear Physics, Legnaro National Laboratories, Viale dell' Università, 2, 35020 Legnaro, Padua (Italy); Felicis, Daniele de, E-mail: daniele.defelicis@uniroma3.it [University of Rome “Roma TRE”, Via della Vasca Navale, 79, 00146 Rome (Italy); Bemporad, Edoardo, E-mail: edoardo.bemporad@uniroma3.it [University of Rome “Roma TRE”, Via della Vasca Navale, 79, 00146 Rome (Italy); Johnson, Richard R., E-mail: richard.johnson@teambest.com [BEST Cyclotron Systems Inc., 8765 Ash Street Unit 7, Vancouver BC V6P 6T3 (Canada); Palmieri, Vincenzo, E-mail: Vincenzo.Palmieri@lnl.infn.it [National Institute of Nuclear Physics, Legnaro National Laboratories, Viale dell' Università, 2, 35020 Legnaro, Padua (Italy); University of Padua, Padua (Italy)

    2015-09-30

    Chemically inert coatings on Havar{sup ®} entrance foils of the targets for [{sup 18}F] production via proton irradiation of enriched water at pressurized conditions are needed to decrease the amount of ionic contaminants released from Havar{sup ®}. During current investigation, magnetron sputtered niobium and niobium oxide were chosen as the candidates for protective coatings because of their superior chemical resistance. Aluminated quartz substrates allowed us to verify the protection efficiency of the desirable coatings as diffusion barriers. Two modeling corrosion tests based on the extreme susceptibility of aluminum to liquid gallium and acid corrosion were applied. As far as niobium coatings obtained by magnetron sputtering are columnar, the grain boundaries provide a fast diffusion path for active species of corrosive media to penetrate and to corrode the substrate. Amorphous niobium oxide films obtained by reactive magnetron sputtering showed superior barrier properties according to the corrosion tests performed. In order to prevent degrading of brittle niobium oxide at high pressures, multilayers combining high ductility of niobium with superior diffusion barrier efficiency of niobium oxide were proposed. The intercalation of niobium oxide interlayers was proved to interrupt the columnar grain growth of niobium during sputtering, resulting in improved diffusion barrier efficiency of obtained multilayers. The thin layer multilayer coating architecture with 70 nm bi-layer thickness was found preferential because of higher thermal stability. - Highlights: • Diffusion barrier efficiency of niobium, niobium oxide and their multilayers was studied. • The intercalation of niobium oxide layers interrupted the columnar grain growth of niobium. • The bilayer architectures influenced the stability of the multilayer coatings. • The thin layer multilayer coating with 70 nm double-layer was found superior.

  16. Measurements of gas and volatile element production rates from an irradiated molten lead and lead-bismuth spallation target with proton beams of 1 and 1.4 GeV

    International Nuclear Information System (INIS)

    Tall, Y.

    2008-03-01

    The integrated project EUROTRANS (European Research Programme for the Transmutation of High Level Nuclear Waste in an Accelerator Driven System) of the 6. EURATOM Framework Programme aims to demonstrate the transmutation of radioactive waste in ADS (Accelerator Driven Sub-critical system). It will carry out a first advanced design of an experimental facility to demonstrate the technical feasibility of transmutation, and will produce a conceptual design of an industrial facility dedicated to transmutation. An ADS consists of three fundamental elements: the accelerator of protons, the sub-critical core and the spallation target. SUBATECH (physique Sub-Atomique et des Technologies associees) laboratory is involved to the study of the chosen liquid lead-bismuth as a spallation ADS target. The irradiation of liquid lead-bismuth target with energetic proton beam generates in addition to neutrons, volatile and radioactive residues. In order to determine experimentally the production rates of gas and volatile elements following a spallation reaction in a lead-bismuth target, the experiment IS419 was performed at the ISOLDE facility at CERN (Centre Europeen de la Recherche Nucleaire). This experiment constitutes the frame of the thesis whose main objective is to assess and study the production and release rates of many gas and volatile element from the irradiated lead-bismuth target with an energetic proton beam. The obtained data are compared to Monte Carlo simulation code (MCNPX) results in order to test the intranuclear cascade model of Bertini and of Cugnon, and the evaporation options of Dresner and Schmidt. (author)

  17. Decreased repopulation as well as increased reoxygenation contribute to the improvement in local control after targeting of the EGFR by C225 during fractionated irradiation.

    NARCIS (Netherlands)

    Krause, M.; Ostermann, G.; Petersen, C.; Yaromina, A.; Hessel, F.; Harstrick, A.; Kogel, A.J. van der; Thames, H.D.; Baumann, M.

    2005-01-01

    BACKGROUND AND PURPOSE: Inhibition of repopulation and enhanced reoxygenation has been suggested to contribute to improvement of local tumour control after fractionated irradiation combined with inhibitors of the epidermal growth factor receptor (EGFR). The present study addresses this hypothesis in

  18. The effect of carbon impurities on molybdenum surface morphology evolution under high-flux low-energy helium ion irradiation

    International Nuclear Information System (INIS)

    Tripathi, J.K.; Novakowski, T.J.; Gonderman, S.; Bharadwaj, N.; Hassanein, A.

    2016-01-01

    We report on the role of carbon (C) impurities, in molybdenum (Mo) fuzz evolutions on Mo surface during 100 eV He + ion irradiations. In this study we considered 0.01, 0.05, and 0.5% C + ion impurities in He + ion irradiations. For introducing such tiny C + ion impurities, gas mixtures of He and CH 4 have been chosen in following ratios; 99.95: 0.05, 99.75: 0.25, and 97.5: 2.5. Apart from these three cases, two additional cases, 100% He + ion (for Mo fuzz growth due to only He + ions) and 100% H + ion (for confirming the significance of tiny 0.04–2.0% H + ions in terms of Mo fuzz evolutions on Mo surface, if any), have also been considered. Ion energy (100 eV), ion fluence (2.6 × 10 24  ions m −2 ), and target temperature (923 K) were kept constant for each experiment and their selections were based on our previous studies [1,2]. Our study shows homogeneously populated and highly dense Mo fuzz evolutions on entire Mo surface for 100% He + ion irradiation case. Enhancement of C + ion impurities in He + ions causes a sequential reduction in Mo fuzz evolutions, leading to almost complete prevention of Mo fuzz evolutions for 0.5% C + ion impurity concentrations. Additionally, no fuzz formation for 100% H + ion irradiation at all, were seen (apart from some tiny nano-structuring, in very limited regions). This indicates that there is no significant role of H + ions in Mo fuzz evolutions (at least for such tiny amount, 0.04–2.0% H + ions). The study is significant to understand the behavior of potential high-Z plasma facing components (PFCs), in the, presence of tiny amount of C impurities, for nuclear fusion relevant applications. - Highlights: • Mo Fuzz evolutions due to low-energy high-flux 100% He + ion irradiation. • Sequential reduction in Mo fuzz evolutions with increasing C + ion impurities in He + ions. • Almost complete prevention of Mo fuzz evolutions for 0.5% C + ion impurity in He + ions. • No Mo fuzz formation for 100% H + ion

  19. A prospective three-dimensional analysis about the impact of differences in the clinical target volume in prostate cancer irradiation on normal-tissue exposure. A potential for increasing the benefit/risk ratio

    International Nuclear Information System (INIS)

    Hille, A.; Toews, N.; Schmidberger, H.; Hess, C.F.

    2005-01-01

    Background and purpose: rectal toxicity following external-beam irradiation of prostate cancer correlates with the exposed percentage of rectal volume. Recently, it has been recommended to reduce the volume of the seminal vesicles that should be included in the clinical target volume (CTV). The purpose of this study was to quantitatively assess the impact of this CTV reduction on the expected rectal and bladder dose sparing. Patients and methods: 14 patients with localized prostate cancer undergoing external-beam radiotherapy were investigated. The prostate, the prostate + entire seminal vesicles, or the prostate + proximal seminal vesicles were delineated as CTV. Treatment plans were generated and compared concerning rectum and bladder dose-volume histograms (DVHs). Results: the exposure of rectum and bladder volume was significantly lower in case of irradiation of the prostate only compared to inclusion of the proximal or entire seminal vesicles into the CTV. The reduction of the CTV from prostate + entire seminal vesicles to prostate + proximal seminal vesicles led to a significant reduction of the rectal and bladder dose exposure. Conclusion: reduction of the CTV to the prostate only, or to the prostate + proximal seminal vesicles led to significant rectal and bladder dose sparing compared to irradiation of the prostate + entire seminal vesicles. In patients with a higher risk for seminal vesicles involvement, irradiation of the prostate + proximal seminal vesicles should be preferred. In case of a need for irradiation of the entire seminal vesicles, patients should be informed about a higher risk for chronic rectal toxicity and, possibly, for bladder complications. (orig.)

  20. The impact of pulsed irradiation upon neutron activation calculations for inertial and magnetic fusion energy power plants

    International Nuclear Information System (INIS)

    Latkowski, J.F.; Sanz, J.; Vujic, J.L.

    1996-01-01

    Inertial fusion energy (IFE) and magnetic fusion energy (MFE) power plants will probably operate in a pulsed mode. The two different schemes, however, will have quite different time periods. Typical repetition rates for IFE power plants will be 1-5 Hz. MFE power plants will ramp up in current for about 1 hour, shut down for several minutes, and repeat the process. Traditionally, activation calculations for IFE and MFE power plants have assumed continuous operation and used either the ''steady state'' (SS) or ''equivalent steady state'' (ESS) approximations. It has been suggested recently that the SS and ESS methods may not yield accurate results for all radionuclides of interest. The present work expands that of Sisolak, et al. by applying their formulae to conditions which might be experienced in typical IFE and MFE power plants. In addition, complicated, multi-step reaction/decay chains are analyzed using an upgraded version of the ACAB radionuclide generation/depletion code. Our results indicate that the SS method is suitable for application to MFE power plant conditions. We also find that the ESS method generates acceptable results for radionuclides with half-lives more than a factor of three greater than the time between pulses. For components that are subject to 0.05 Hz (or more frequent) irradiation (such as coolant), use of the ESS method is recommended. For components or materials that are subject to less frequent irradiation (such as high-Z target materials), pulsed irradiation calculations should be used

  1. Food irradiation

    International Nuclear Information System (INIS)

    Soothill, R.

    1987-01-01

    The issue of food irradiation has become important in Australia and overseas. This article discusses the results of the Australian Consumers' Association's (ACA) Inquiry into food irradiation, commissioned by the Federal Government. Issues discussed include: what is food irradiation; why irradiate food; how much food is consumer rights; and national regulations

  2. Food irradiation

    International Nuclear Information System (INIS)

    Lindqvist, H.

    1996-01-01

    This paper is a review of food irradiation and lists plants for food irradiation in the world. Possible applications for irradiation are discussed, and changes induced in food from radiation, nutritional as well as organoleptic, are reviewed. Possible toxicological risks with irradiated food and risks from alternative methods for treatment are also brought up. Ways to analyze weather food has been irradiated or not are presented. 8 refs

  3. Studies of the effect of irradiation in a nuclear reactor, of targets containing Mo used for the preparation of 99Mo gel, material that constitutes the 99Mo - 99mTc generators

    International Nuclear Information System (INIS)

    Nieto, Renata Correa

    2004-01-01

    The most used radioisotope in Nuclear Medicine is 99m Tc, obtained in the 99 Mo - 99m Tc generator form. 99 Mo can be produced by several nuclear reactions in Cyclotron and Reactor. The production in Cyclotron is not technically and commercially feasible. The production in Nuclear Reactor can be made in two ways: 235 U fission and 99 Mo (n,γ) 99 Mo reaction. A project aiming the production of 99 Mo by activation of Mo is under way at IPEN, producing a gel type MoZr generator. There are two ways of preparing the gel and the generators: by irradiating MoO 3 and preparing the gel or by the preparation of the gel and further irradiation. This work consists in the study of the irradiation effects in several targets containing Mo for the production of 99 Mo by the 98 Mo (n,γ) 99 Mo reaction and further preparation of the gel for use as a gel type 99 Mo - 99m Tc generator. Three rinds of gel were studied: zirconium, titanium and cerium molybdate, and their morphology, infrared structure and elution yield of 99m Tc were analysed. The best results were achieved with the generators prepared with MoZr post formed gel, with amorphous structure and better elution yields. The pre formed gel induced crystallinity and worst performance of the generators. (author)

  4. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Gruenewald, T

    1985-01-01

    Food irradiation has become a matter of topical interest also in the Federal Republic of Germany following applications for exemptions concerning irradiation tests of spices. After risks to human health by irradiation doses up to a level sufficient for product pasteurization were excluded, irradiation now offers a method suitable primarily for the disinfestation of fruit and decontamination of frozen and dried food. Codex Alimentarius standards which refer also to supervision and dosimetry have been established; they should be adopted as national law. However, in the majority of cases where individual countries including EC member-countries so far permitted food irradiation, these standards were not yet used. Approved irradiation technique for industrial use is available. Several industrial food irradiation plants, partly working also on a contractual basis, are already in operation in various countries. Consumer response still is largely unknown; since irradiated food is labelled, consumption of irradiated food will be decided upon by consumers.

  5. Simulation Study of Using High-Z EMA to Suppress Recoil Protons Crosstalk in Scintillating Fiber Array for 14.1 MeV Neutron Imaging

    Science.gov (United States)

    Jia, Qinggang; Hu, Huasi; Zhang, Fengna; Zhang, Tiankui; Lv, Wei; Zhan, Yuanpin; Liu, Zhihua

    2013-12-01

    This paper studies the effect of a high-Z extra mural absorber (EMA) to improve the spatial resolution of a plastic (polystyrene) scintillating fiber array for 14.1 MeV fusion neutron imaging. Crosstalk induced by recoil protons was studied, and platinum (Pt) was selected as EMA material, because of its excellent ability to suppress the recoil protons penetrating the fibers. Three common fiber arrays (cylindrical scintillating fibers in square and hexagonal packing arrangements and square scintillating fibers) were simulated using the Monte Carlo method for evaluating the effect of Pt-EMA in improving spatial resolution. It is found that the resolution of the 100 μm square fiber array can be improved from 1.7 to 3.4 lp/mm by using 10- μm-thick Pt-EMA; comparatively, using an array with thinner square fibers (50 μm) only obtains a resolution of 2.1 lp/mm. The packing fraction decreases with the increase of EMA thickness. Our results recommend the use of 10 μm Pt-EMA for the square and the cylindrical (hexagonal packing) scintillating fiber arrays with fibers of 50-200 μm in the cross-sectional dimension. Besides, the dead-zone material should be replaced by high-Z material for the hexagonal packing cylindrical fiber array with fibers of 50-200 μm in diameter. Tungsten (W) and gold (Au) are also used as EMA in the three fiber arrays as a comparison. The simulation results show that W can be used at a lower cost, and Au does not have any advantages in cost and resolution improvement.

  6. Investigation of the compression of high-aspect targets irradiated with a laser pulse of the second harmonic of the Iskra-4 iodine laser

    International Nuclear Information System (INIS)

    Bel'kov, S.A.; Bessarab, A.V.; Voronich, I.N.; Garanin, S.G.; Dolgoleva, G.V.; Zaretskii, A.I.; Izgorodin, V.M.; Ilyushechkin, B.N.; Kochemasov, G.G.; Kunin, A.V.; Martynenko, S.P.; Merkulov, S.G.; Rukavishnikov, N.N.; Ryadov, A.V.; Suslov, N.A.; Sukharev, S.A.

    1992-01-01

    Theoretical modeling of experiments on the compression of targets under exploding pusher shell conditions, carried out at the Iskra-4 facility with the iodine laser pulsed at its fundamental frequency (λ= 1.315 μm) showed a correlation between the increase in the discrepancy between the calculated and experimental neutron yields and increase of the aspect ratio of the shell of the target used in the experiment. After conversion of the Iskra-4 facility to generate the second harmonic and improving the beam uniformity in the region of the target, a series of experiments was carried out on the compression of high-aspect targets A s > 300. In this series a record neutron yield for this installation, N = 6 x 10 7 , was obtained in experiments with glass-shell targets

  7. Graphite targets at LAMPF

    International Nuclear Information System (INIS)

    Brown, R.D.; Grisham, D.L.

    1983-01-01

    Rotating polycrystalline and stationary pyrolytic graphite target designs for the LAMPF experimental area are described. Examples of finite element calculations of temperatures and stresses are presented. Some results of a metallographic investigation of irradiated pyrolytic graphite target plates are included, together with a brief description of high temperature bearings for the rotating targets

  8. Experimental and theoretical study of radionuclide production on the electronuclear plant target and construction materials irradiated by 1.5 GeV and 130 MeV protons

    International Nuclear Information System (INIS)

    Titarenko, Yu.E.; Karpikhin, E.I.; Smolyakov, A.F.; Igumnov, M.M.; Stepanov, N.V.; Kazaritsky, V.D.; Batyaev, V.F.; Shvedov, O.V.; Mashnik, S.G.; Gabriel, T.A.

    1997-01-01

    Experimental and calculated results are presented for the yields of residual nuclei in 63 Cu, 65 Cu, 206 Pb, 207 Pb, 208 Pb, and 209 Bi targets irradiated to 1.5 GeV and 130 MeV protons and in 59 Co target irradiated to 1.2 GeV protons extracted from the ITEP accelerator. The nuclide yields were found by gamma-spectrometry with a GC-2518 Ge detector, a 1510 module, and a S-100 plate that, as an integral part of IBM PC, emulates a multichannel analyzer. The gamma-spectrometry 60 Co 1332.5 keV line energy resolution was 1.8 keV. The gamma-spectra were processed by the ASPRO code. The SIGMA code with the GDISP radionuclide database was used to identify the gamma-lines and to calculate the respective cross sections. The monitor reactions was 27 Al(p,3pn) 24 Na. The experimental generation cross sections of end products are compared with the respective values calculated by the HETC, INUCL, and CEM95 codes that simulate hadron-nucleus interactions. 12 refs., 3 figs., 7 tabs

  9. Neutronic and thermal-hydraulic analysis of devices for irradiation of LEU targets type of UALx-Al and U-Ni to production of 99Mo in reactor IEA-R1 and RMB

    International Nuclear Information System (INIS)

    Domingos, Douglas Borges

    2014-01-01

    In this work neutronic and thermal-hydraulic analyses were made to compare three types of targets (UAl 2 -Al, U-Ni cylindrical and U-Ni plate) used for the production of 99 Mo by fission of 235 U. Some experiments were conducted to validate the neutronic and thermal-hydraulics methodologies used in this work. For the neutronic calculations the computational programs NJOY99.0, AMPX-II and HAMMERTECHNION were used to generate the cross sections. SCALE 6.0 and CITATION computational programs were used for three-dimensional calculations of the reactor cores, fuel burning and the production of 99 Mo. The computational programs MTRCR-IEAR1 and ANSYS CFX were used to calculate the thermal and hydraulic parameters of the irradiation devices and for comparing them to limits and design criteria. First were performed neutronic and thermal-hydraulic analyzes for the reactor IEA-R1 with the targets of UAl 2 -Al (10 mini plates). Analyses have shown that the total activity obtained for 99 Mo on the mini plates does not meet the demand of Brazilian hospitals (450 Ci/week) and that no limit of thermo-hydraulic design is overtaken. Next, the same calculations were performed for the three target types in Multipurpose Brazilian Reactor (MBR). The neutronic analyzes demonstrated that the three targets meet the demand of Brazilian hospitals. The thermal hydraulic analysis shows that a minimum speed of 7 m/s for the target UAl 2 -Al, 8 m/s for the cylindrical target U-Ni and 9 m/s for the target U-Ni plate will be necessary in the irradiation device to not exceed the design limits. Were performed experiments using a test bench for validate the methodologies for the thermal-hydraulic calculation. The experiments performed to validate the neutronic calculations were made in the reactor IPEN/MB-01. All experiments were simulated with the methodologies described above and the results compared. The simulations results showed good agreement with experimental results. (author)

  10. 18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer

    International Nuclear Information System (INIS)

    Wang Hui; Vees, Hansjoerg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

    2009-01-01

    Background and purpose: We evaluate the contribution of 18 F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Materials and methods: Seventeen patients with local-only recurrent prostate cancer (median = 5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of 18 F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the 18 F-choline-based GTVs. These included manual delineation of contours (GTV man ) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV 40% and GTV 50% ), signal-to-background ratio-based adaptive thresholding (GTV SBR ), and a region growing (GTV RG ) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Results: Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p = 0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Conclusions: Semi-automated segmentation techniques for 18 F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

  11. 18F-fluorocholine PET-guided target volume delineation techniques for partial prostate re-irradiation in local recurrent prostate cancer.

    Science.gov (United States)

    Wang, Hui; Vees, Hansjörg; Miralbell, Raymond; Wissmeyer, Michael; Steiner, Charles; Ratib, Osman; Senthamizhchelvan, Srinivasan; Zaidi, Habib

    2009-11-01

    We evaluate the contribution of (18)F-choline PET/CT in the delineation of gross tumour volume (GTV) in local recurrent prostate cancer after initial irradiation using various PET image segmentation techniques. Seventeen patients with local-only recurrent prostate cancer (median=5.7 years) after initial irradiation were included in the study. Rebiopsies were performed in 10 patients that confirmed the local recurrence. Following injection of 300 MBq of (18)F-fluorocholine, dynamic PET frames (3 min each) were reconstructed from the list-mode acquisition. Five PET image segmentation techniques were used to delineate the (18)F-choline-based GTVs. These included manual delineation of contours (GTV(man)) by two teams consisting of a radiation oncologist and a nuclear medicine physician each, a fixed threshold of 40% and 50% of the maximum signal intensity (GTV(40%) and GTV(50%)), signal-to-background ratio-based adaptive thresholding (GTV(SBR)), and a region growing (GTV(RG)) algorithm. Geographic mismatches between the GTVs were also assessed using overlap analysis. Inter-observer variability for manual delineation of GTVs was high but not statistically significant (p=0.459). In addition, the volumes and shapes of GTVs delineated using semi-automated techniques were significantly higher than those of GTVs defined manually. Semi-automated segmentation techniques for (18)F-choline PET-guided GTV delineation resulted in substantially higher GTVs compared to manual delineation and might replace the latter for determination of recurrent prostate cancer for partial prostate re-irradiation. The selection of the most appropriate segmentation algorithm still needs to be determined.

  12. Food irradiation

    International Nuclear Information System (INIS)

    Sato, Tomotaro; Aoki, Shohei

    1976-01-01

    Definition and significance of food irradiation were described. The details of its development and present state were also described. The effect of the irradiation on Irish potatoes, onions, wiener sausages, kamaboko (boiled fish-paste), and mandarin oranges was evaluated; and healthiness of food irradiation was discussed. Studies of the irradiation equipment for Irish potatoes in a large-sized container, and the silo-typed irradiation equipment for rice and wheat were mentioned. Shihoro RI center in Hokkaido which was put to practical use for the irradiation of Irish potatoes was introduced. The state of permission of food irradiation in foreign countries in 1975 was introduced. As a view of the food irradiation in the future, its utilization for the prevention of epidemics due to imported foods was mentioned. (Serizawa, K.)

  13. Growing central axons deprived of normal target neurones by neonatal X-ray irradiation still terminate in a precisely laminated fashion

    International Nuclear Information System (INIS)

    Laurberg, S.; Hjorth-Simonsen, A.

    1977-01-01

    Some studies are described on rat pups. The object was to study the fate of axons that normally terminate in a highly selective laminar fashion in the molecular layer of the medial limb of the dentate gyrus of the mammalian cerebral cortex when this is removed by neonatal X-ray irradiation. The rats were shielded with Pb, except for a field above the hippocampus and the dentate gyrus, and exposed to X-rays from a 250 kV source at a distance of 34 cm. (U.K.)

  14. Gamma irradiator

    International Nuclear Information System (INIS)

    Simonet, G.

    1986-09-01

    Fiability of devices set around reactors depends on material resistance under irradiation noticeably joints, insulators, which belongs to composition of technical, safety or physical incasurement devices. The irradiated fuel elements, during their desactivation in a pool, are an interesting gamma irradiation device to simulate damages created in a nuclear environment. The existing facility at Osiris allows to generate an homogeneous rate dose in an important volume. The control of the element distances to irradiation box allows to control this dose rate [fr

  15. Food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    The article explains what radiation does to food to preserve it. Food irradiation is of economic importance to Canada because Atomic Energy of Canada Limited is the leading world supplier of industrial irradiators. Progress is being made towards changing regulations which have restricted the irradiation of food in the United States and Canada. Examples are given of applications in other countries. Opposition to food irradiation by antinuclear groups is addressed

  16. Test and implementation of position sensors on load and unload [18O]H2O control valve of the target used in 18F - production by proton irradiation

    International Nuclear Information System (INIS)

    Costa, Osvaldo L. da; Sciani, Valdir

    2009-01-01

    The radionuclide 18 F used to produce the radiopharmaceutical [ 18 F]FDG has 109.7 min of half-life, becoming your productive chain so peculiar, because since the beginning of [ 18 O]H 2 O irradiation until the PET-CT exam there is a period about six hours, and any procedure fail in the productive chain will result in a delay to the PET CT exam. The absence of the position signs from [ 18 O]H 2 O load and unload valve of the target may result in 18 F production loss and even area contamination around the target. In this paper, three types of position sensors, into cyclotron radionuclides production environment in Cyclotron Accelerator Center from IPEN-CNEN/SP were tested. The tests were an indicative to discover the fitter sensor to the [ 18 O]H 2 O load and unload valve from target used in [ 18 F]fluoride production. After finding the fitter sensor, it was implemented in 18 F- target, supplying the correct position from [ 18 O]H 2 O load and unload valve to programmable logic controller, that had the software modified, respecting in this way the valve position. By this way, it was possible to reduce the incidence of fails, increasing the reliability in [ 18 F]FDG productive chain. (author)

  17. Food irradiation

    International Nuclear Information System (INIS)

    Beyers, M.

    1977-01-01

    The objectives of food irradiation are outlined. The interaction of irradiation with matter is then discussed with special reference to the major constituents of foods. The application of chemical analysis in the evaluation of the wholesomeness of irradiated foods is summarized [af

  18. Neutron capture therapy (NCT) and in-hospital neutron irradiator (IHNI) a new technology on binary targeting radiation therapy of cancer

    International Nuclear Information System (INIS)

    Zhou Yongmao

    2009-01-01

    BNCT is finally becoming 'a new option against cancer'. The difficulties for its development progress of that firstly is to improve the performance of boron compounds,secondly, it is the requirements of quantification and accuracy upon radiation dosimetry evaluation in clinical trials. Furthermore, that is long anticipation on hospital base neutron sources. It includes dedicated new NCT reactor, accelerator based neutron sources, and isotope source facilities. In addition to reactors, so far, the technology of other types of sources for clinical trials is not yet completely proven. The In-Hospital Neutron Irradiator specially designed for NCT, based on the MNSR successfully developed by China, can be installed inside or near the hospital and operated directly by doctors. The Irradiator has two neutron beams for respective treatment of the shallow and deep tumors. It is expected to initiate operation in the end of this year. It would provide a safe, low cost, and effective treatment tool for the NCT routine application in near future. (authors)

  19. Irradiation-Induced Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Birtcher, R.C.; Ewing, R.C.; Matzke, Hj.; Meldrum, A.; Newcomer, P.P.; Wang, L.M.; Wang, S.X.; Weber, W.J.

    1999-08-09

    This paper summarizes the results of the studies of the irradiation-induced formation of nanostructures, where the injected interstitials from the source of irradiation are not major components of the nanophase. This phenomena has been observed by in situ transmission electron microscopy (TEM) in a number of intermetallic compounds and ceramics during high-energy electron or ion irradiations when the ions completely penetrate through the specimen. Beginning with single crystals, electron or ion irradiation in a certain temperature range may result in nanostructures composed of amorphous domains and nanocrystals with either the original composition and crystal structure or new nanophases formed by decomposition of the target material. The phenomenon has also been observed in natural materials which have suffered irradiation from the decay of constituent radioactive elements and in nuclear reactor fuels which have been irradiated by fission neutrons and other fission products. The mechanisms involved in the process of this nanophase formation are discussed in terms of the evolution of displacement cascades, radiation-induced defect accumulation, radiation-induced segregation and phase decomposition, as well as the competition between irradiation-induced amorphization and recrystallization.

  20. Food irradiation

    International Nuclear Information System (INIS)

    Macklin, M.

    1987-01-01

    The Queensland Government has given its support the establishment of a food irradiation plant in Queensland. The decision to press ahead with a food irradiation plant is astonishing given that there are two independent inquiries being carried out into food irradiation - a Parliamentary Committee inquiry and an inquiry by the Australian Consumers Association, both of which have still to table their Reports. It is fair to assume from the Queensland Government's response to date, therefore, that the Government will proceed with its food irradiation proposals regardless of the outcomes of the various federal inquiries. The reasons for the Australian Democrats' opposition to food irradiation which are also those of concerned citizens are outlined

  1. Food irradiation

    International Nuclear Information System (INIS)

    Duchacek, V.

    1989-01-01

    The ranges of doses used for food irradiation and their effect on the processed foods are outlined. The wholesomeness of irradiated foods is discussed. The present food irradiation technology development in the world is described. A review of the irradiated foods permitted for public consumption, the purposes of food irradiaton, the doses used and a review of the commercial-scale food irradiators are tabulated. The history and the present state of food processing in Czechoslovakia are described. (author). 1 fig., 3 tabs., 13 refs

  2. Irradiated foods

    International Nuclear Information System (INIS)

    Darrington, Hugh

    1988-06-01

    This special edition of 'Food Manufacture' presents papers on the following aspects of the use of irradiation in the food industry:- 1) an outline view of current technology and its potential. 2) Safety and wholesomeness of irradiated and non-irradiated foods. 3) A review of the known effects of irradiation on packaging. 4) The problems of regulating the use of irradiation and consumer protection against abuse. 5) The detection problem - current procedures. 6) Description of the Gammaster BV plant in Holland. 7) World outline review. 8) Current and future commercial activities in Europe. (U.K.)

  3. A new three-dimensional conformal radiotherapy (3DCRT) technique for large breast and/or high body mass index patients: evaluation of a novel fields assessment aimed to reduce extra–target-tissue irradiation

    Science.gov (United States)

    Stimato, Gerardina; Ippolito, Edy; Silipigni, Sonia; Venanzio, Cristina Di; Gaudino, Diego; Fiore, Michele; Trodella, Lucio; D'Angelillo, Rolando Maria; Ramella, Sara

    2016-01-01

    Objective: To develop an alternative three-dimensional treatment plan with standardized fields class solution for whole-breast radiotherapy in patients with large/pendulous breast and/or high body mass index (BMI). Methods: Two treatment plans [tangential fields and standardized five-fields technique (S5F)] for a total dose of 50 Gy/25 fractions were generated for patients with large breasts [planning target volume (PTV) >1000 cm3 and/or BMI >25 kg m−2], supine positioned. S5F plans consist of two wedged tangential beams, anteroposterior: 20° for the right breast and 340° for the left breast, and posteroanterior: 181° for the right breast and 179° for the left breast. A field in field in medial–lateral beam and additional fields were added to reduce hot spot areas and extra–target-tissue irradiation and to improve dose distribution. The percentage of PTV receiving 95% of the prescribed dose (PTV V95%), percentage of PTV receiving 105% of the prescribed dose (PTV V105%), maximal dose to PTV (PTV Dmax), homogeneity index (HI) and conformity index were recorded. V10%, V20%, V105% and V107% of a “proper” normal tissue structure (body-PTV healthy tissue) were recorded. Statistical analyses were performed using SYSTAT v.12.0 (SPSS, Chicago, IL). Results: In 38 patients included, S5F improved HI (8.4 vs 10.1; p ≤ 0.001) and significantly reduced PTV Dmax and PTV V105%. The extra–target-tissue irradiation was significantly reduced using S5F for V105% (cm3) and V107% (cm3) with a very high difference in tissue irradiation (46.6 vs 3.0 cm3, p ≤ 0.001 for V105% and 12.2 vs 0.0 cm3, p ≤ 0.001 for V107% for tangential field and S5F plans, respectively). Only a slight increase in low-dose extra–target-tissue irradiation (V10%) was observed (2.2719 vs 1.8261 cm3, p = 0.002). Conclusion: The S5F technique in patients with large breast or high BMI increases HI and decreases hot spots in extra-target-tissues and can therefore be

  4. TARGET STUDIES WITH BNL E951 AT THE AGS

    International Nuclear Information System (INIS)

    KIRK, H.; BROWN, K.; FERNOW, R.; FINFROCK, C.; GASSNER, D.; GREENE, G.; KAHN, S.; KING, B.; PRIGL, R.; SAMULYAK, R.; SCADUTO, J.; SIMOS, N.; THIEBERGER, P.; TSANG, T.; WANG, H.; WEGGEL, R.

    2001-01-01

    We report initial results of exposing low-Z solid and high-Z liquid targets to 150-ns, 4 x 10 12 proton pulses with spot sizes on the order of 1 to 2 mm. The energy deposition density approached 100 J/g. Diagnostics included fiberoptic strain sensors on the solid target and high-speed photography of the liquid targets. This work is part of the R and D program of the Neutrino Factory and Muon Collider Collaboration

  5. Cosmic Microwave Background as a Thermal Gas of SU(2 Photons: Implications for the High-z Cosmological Model and the Value of H0

    Directory of Open Access Journals (Sweden)

    Steffen Hahn

    2017-01-01

    Full Text Available Presently, we are facing a 3σ tension in the most basic cosmological parameter, the Hubble constant H0. This tension arises when fitting the Lambda-cold-dark-matter model (ΛCDM to the high-precision temperature-temperature (TT power spectrum of the Cosmic Microwave Background (CMB and to local cosmological observations. We propose a resolution of this problem by postulating that the thermal photon gas of the CMB obeys an SU(2 rather than U(1 gauge principle, suggesting a high-z cosmological model which is void of dark-matter. Observationally, we rely on precise low-frequency intensity measurements in the CMB spectrum and on a recent model independent (low-z extraction of the relation between the comoving sound horizon rs at the end of the baryon drag epoch and H0 (rsH0=const. We point out that the commonly employed condition for baryon-velocity freeze-out is imprecise, judged by a careful inspection of the formal solution to the associated Euler equation. As a consequence, the above-mentioned 3σ tension actually transforms into a 5σ discrepancy. To make contact with successful low-z  ΛCDM cosmology we propose an interpolation based on percolated/depercolated vortices of a Planck-scale axion condensate. For a first consistency test of such an all-z model we compute the angular scale of the sound horizon at photon decoupling.

  6. Equation of state of dense plasmas: Orbital-free molecular dynamics as the limit of quantum molecular dynamics for high-Z elements

    Energy Technology Data Exchange (ETDEWEB)

    Danel, J.-F.; Blottiau, P.; Kazandjian, L.; Piron, R.; Torrent, M. [CEA, DAM, DIF, 91297 Arpajon (France)

    2014-10-15

    The applicability of quantum molecular dynamics to the calculation of the equation of state of a dense plasma is limited at high temperature by computational cost. Orbital-free molecular dynamics, based on a semiclassical approximation and possibly on a gradient correction, is a simulation method available at high temperature. For a high-Z element such as lutetium, we examine how orbital-free molecular dynamics applied to the equation of state of a dense plasma can be regarded as the limit of quantum molecular dynamics at high temperature. For the normal mass density and twice the normal mass density, we show that the pressures calculated with the quantum approach converge monotonically towards those calculated with the orbital-free approach; we observe a faster convergence when the orbital-free approach includes the gradient correction. We propose a method to obtain an equation of state reproducing quantum molecular dynamics results up to high temperatures where this approach cannot be directly implemented. With the results already obtained for low-Z plasmas, the present study opens the way for reproducing the quantum molecular dynamics pressure for all elements up to high temperatures.

  7. Influence of the reactive atmosphere on the formation of nanoparticles in the plasma plume induced by nanosecond pulsed laser irradiation of metallic targets at atmospheric pressure and high repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Girault, M. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Le Garrec, J.-L.; Mitchell, J.B.A. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Jouvard, J.-M. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Carvou, E. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Menneveux, J.; Yu, J. [Institut Lumière Matière, UMR5306 Université Lyon 1-CNRS, Université de Lyon, 69622 Villeurbanne Cedex (France); Ouf, F.-X. [Institut de Radioprotection et de Sureté Nucléaire IRSN/PSN-RES/SCA/LPMA BP 68, 91192 Gif-Sur-Yvette (France); Carles, S. [Institut de Physique de Rennes, UMR 6251 CNRS-Université de Rennes 1, 35042 Rennes Cedex (France); Potin, V.; Pillon, G.; Bourgeois, S. [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); Perez, J. [Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex (France); Marco de Lucas, M.C., E-mail: delucas@u-bourgogne.fr [Laboratoire Interdisciplinaire Carnot de Bourgogne, UMR 6303 CNRS-Univ. Bourgogne Franche-Comté, 9 Av. A. Savary, BP 47 870, F-21078 Dijon Cedex (France); and others

    2016-06-30

    Highlights: • NPs formed in a plasma-plume during laser irradiation of metals (Al, Ti, Ag) were studied. • In situ SAXS and ex situ TEM, XRD and Raman spectra were measured. • NPs size decreased when increasing the O{sub 2} fraction in a controlled O{sub 2}+N{sub 2} atmosphere. • The oxidation of metal NPs in the plasma restricts the increase of the size of the NPs. - Abstract: The influence of a reactive atmosphere on the formation of nanoparticles (NPs) in the plasma plume generated by nanosecond pulsed laser irradiation of metal targets (Ti, Al, Ag) was probed in situ using Small Angle X-ray Scattering (SAXS). Air and different O{sub 2}–N{sub 2} gas mixtures were used as reactive gas within atmospheric pressure. SAXS results showed the formation of NPs in the plasma-plume with a mean radius varying in the 2–5 nm range. A decrease of the NPs size with increasing the O{sub 2} percentage in the O{sub 2}–N{sub 2} gas mixture was also showed. Ex situ observations by transmission electron microscopy and structural characterizations by X-ray diffraction and Raman spectroscopy were also performed for powders collected in experiments done using air as ambient gas. The stability of the different metal oxides is discussed as being a key parameter influencing the formation of NPs in the plasma-plume.

  8. Characterization of a multi-keV x-ray source produced by nanosecond laser irradiation of a solid target: The influence of laser focus spot and target thickness

    International Nuclear Information System (INIS)

    Hu Guangyue; Zheng Jian; Shen Baifei; Lei Anle; Xu Zhizhan; Liu Shenye; Zhang Jiyan; Yang Jiamin; Ding Yongkun; Hu Xin; Huang Yixiang; Du Huabing; Yi Rongqing

    2008-01-01

    The influence of focus spot and target thickness on multi-keV x-ray sources generated by 2 ns duration laser heated solid targets are investigated on the Shenguang II laser facility. In the case of thick-foil targets, the experimental data and theoretical analysis show that the emission volume of the x-ray sources is sensitive to the laser focus spot and proportional to the 3 power of the focus spot size. The steady x-ray flux is proportional to the 5/3 power of the focus spot size of the given laser beam in our experimental condition. In the case of thin-foil targets, experimental data show that there is an optimal foil thickness corresponding to the given laser parameters. With the given laser beam, the optimal thin-foil thickness is proportional to the -2/3 power of the focus spot size, and the optimal x-ray energy of thin foil is independent of focus spot size

  9. Synthesis of surface molecular imprinted TiO{sub 2}/graphene photocatalyst and its highly efficient photocatalytic degradation of target pollutant under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Cui, E-mail: laicui@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Wang, Man-Man [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Zeng, Guang-Ming, E-mail: zgming@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China); Liu, Yun-Guo; Huang, Dan-Lian; Zhang, Chen; Wang, Rong-Zhong; Xu, Piao; Cheng, Min; Huang, Chao; Wu, Hai-Peng; Qin, Lei [College of Environmental Science and Engineering, Hunan University, Changsha 410082, Hunan (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082, Hunan (China)

    2016-12-30

    Highlights: • The surface molecular imprinting technique was successfully combined with photocatalyst. • Molecularly imprinted photocatalyst exhibits recognition ability to the target molecules. • MIP-TiO{sub 2}/GR shows higher adsorption capacity and selectivity than NIP-TiO{sub 2}/GR. • The photocatalytic activity of MIP-TiO{sub 2}/GR is enhanced for target molecules. - Abstract: The molecular imprinted TiO{sub 2}/graphene photocatalyst (MIP-TiO{sub 2}/GR) was successfully prepared with bisphenol A (BPA) as the template molecule (target pollutant) and o-phenylenediamine (OPDA) as functional monomers by the surface molecular imprinting method. The combination between BPA and OPDA led to the formation of the precursor, and the subsequent polymerization of OPDA initiated by ultraviolet radiation can ensure the realization of MIP-TiO{sub 2}/GR. The samples were characterized by SEM, EDS, XRD, BET, UV–vis DRS and Zeta potential. In addition, adsorption capacities, adsorption selectivity and visible light photocatalytic performances of MIP-TiO{sub 2}/GR and non-imprinted TiO{sub 2}/graphene (NIP-TiO{sub 2}/GR) were evaluated. Moreover, the effects of pH and initial BPA concentration on removal efficiency of BPA were also investigated. The results showed that MIP-TiO{sub 2}/GR exhibited better adsorption capacity and adsorption selectivity towards the template molecule compared to NIP-TiO{sub 2}/GR due to the imprinted cavities on the surface of MIP-TiO{sub 2}/GR. Moreover, the photocatalytic activity of MIP-TiO{sub 2}/GR toward the target molecules was stronger than that of NIP-TiO{sub 2}/GR as a result of large adsorption capacity to target molecules and narrow band gap energy on MIP-TiO{sub 2}/GR. Therefore, modifying the photocatalyst by the surface molecular imprinting is a promising method to improve the molecule recognition and photocatalytic efficiency of photocatalyst for target pollutant.

  10. Foodstuff irradiation

    International Nuclear Information System (INIS)

    1982-01-01

    Report written on behalf of the Danish Food Institute summarizes national and international rules and developments within food irradiation technology, chemical changes in irradiated foodstuffs, microbiological and health-related aspects of irradiation and finally technological prospects of this conservation form. Food irradiatin has not been hitherto applied in Denmark. Radiation sources and secondary radiation doses in processed food are characterized. Chemical changes due to irradiation are compared to those due to p.ex. food heating. Toxicological and microbiological tests and their results give no unequivocal answer to the problem whether a foodstuff has been irradiated. The most likely application fields in Denmark are for low radiation dosis inhibition of germination, riping delay and insecticide. Medium dosis (1-10 kGy) can reduce bacteria number while high dosis (10-50 kGy) will enable total elimination of microorganisms and viruses. Food irradiation can be acceptable as technological possibility with reservation, that further studies follow. (EG)

  11. FY 2013 Summary Report: Post-Irradiation Examination of Zircaloy-4 Samples in Target Capsules and Initiation of Bending Fatigue Testing for Used Nuclear Fuel Vibration Integrity Investigations

    Energy Technology Data Exchange (ETDEWEB)

    Howard, Richard H [ORNL; Yan, Yong [ORNL; Wang, Jy-An John [ORNL; Ott, Larry J [ORNL; Howard, Rob L [ORNL

    2013-10-01

    This report documents ongoing work performed at Oak Ridge National Laboratory (ORNL) for the Department of Energy, Office of Fuel Cycle Technology Used Fuel Disposition Campaign (UFDC), and satisfies the deliverable for milestone M2FT-13OR0805041, “Data Report on Hydrogen Doping and Irradiation in HFIR.” This work is conducted under WBS 1.02.08.05, Work Package FT-13OR080504 ST “Storage and Transportation-Experiments – ORNL.” The objectives of work packages that make up the S&T Experiments Control Account are to conduct the separate effects tests (SET) and small-scale tests that have been identified in the Used Nuclear Fuel Storage and Transportation Data Gap Prioritization (FCRD-USED-2012-000109). In FY 2013, the R&D focused on cladding and container issues and small-scale tests as identified in Sections A-2.9 and A-2.12 of the prioritization report.

  12. Dose distribution of non-coplanar irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Fukui, Toshiharu; Wada, Yoichi; Takenaka, Eiichi

    1987-02-01

    Non-coplanar irradiations were applied to the treatment of brain tumor. The dose distribution around the target area due to non-coplanar irradiation was half less than the dose when coplanar irradiation used. Integral volume dose due to this irradiation was not always less than that due to conventional opposing or rotational irradiation. This irradiation has the better application to the following;as a boost therapy, glioblastoma multiforme;as a radical therapy, recurrent brain tumor, well differentiated brain tumor such as craniopharyngioma, hypophyseal tumor etc and AV-malformation.

  13. Hemibody irradiation

    International Nuclear Information System (INIS)

    Schen, B.C.; Mella, O.; Dahl, O.

    1992-01-01

    In a large number of cancer patients, extensive skeletal metastases or myelomatosis induce vast suffering, such as intolerable pain and local complications of neoplastic bone destruction. Analgetic drugs frequently do not yield sufficient palliation. Irradiation of local fields often has to be repeated, because of tumour growth outside previously irradiated volumes. Wide field irradiation of the lower or upper half of the body causes significant relief of pain in most patients. Adequate pretreatment handling of patients, method of irradiation, and follow-up are of importance to reduce side effects, and are described as they are carried out at the Department of Oncology, Haukeland Hospital, Norway. 16 refs., 2 figs

  14. Experimental and theoretical studies of the yields of residual product nuclei produced in thin Pb and Bi targets irradiated by 40 - 2600 MeV protons

    International Nuclear Information System (INIS)

    Titarenko, Yu. E.; Batyaev, V.F.; Karpikhin, E.I.; Zhivun, V.M.; Ignatyuk, A.V.; Lunev, V.P.; Titarenko, N.N.; Shubin, Yu.N.; Barashenkov, V.S.

    2009-10-01

    The Project is aimed at experimental determining and computer-aided theoretical simulating the independent and cumulative yields of residual radioactive product nuclei in high-energy protonirradiated thin targets made of high-isotopic and natural lead ( 206 Pb, 207 Pb, 208 PB, natPb) and bismuth ( 209 Bi) that are the most probable choice to be the target materials in the acceleratordriven (hybrid) systems (ADS) coupled to a high-current proton accelerator. The yields of residual product nuclei are of great importance when estimating such basic radiation-technology characteristics of the hybrid facility targets as the total target activity, the target 'poisoning', the buildup of long-lived nuclides, the α-activity, the content of low-pressure evaporated nuclides (Hg), the content of the chemically-active nuclides that drastically spoil the corrosion resistance of the facility structure materials, etc. In view of the above, the radioactive product nuclide yields from targets materials were experimentally determined using the ITEP U-10 proton accelerator in 55 measurement runs using the monoisotopic and natural lead ( 206 Pb, 207 Pb, 208 PB, natPb) and bismuth ( 209 Bi) targets within the proton energy range fractionated minutely, namely at 0.04, 0.07, 0.10, 0.8, 1.2, 1.4, 1.6, and 2.6 GeV to cover the entire range of the internuclear hadron cascading. As a result, 5972 cumulative and independent yields of residual radioactive product nuclei, whose lifetimes range from 8 minutes to 32 years, have been measured. Besides, the cross sections for the 27 Al(p,x) 24 Na and 27 Al(p,x)7Be monitor reactions have been measured at the same proton energies together with the 27 Al(n,p) 27 Mg reaction rate that characterizes the neutron background contributions in each experiment. The experimental nuclide yields are determined by the direct γ-spectrometry method. The γ-spectrometer resolution is 1.8 keV in the 1332 keV 60 Co γ-line. The experimental γ-spectra are processed by

  15. High-Frequency Jet Ventilation for Complete Target Immobilization and Reduction of Planning Target Volume in Stereotactic High Single-Dose Irradiation of Stage I Non-Small Cell Lung Cancer and Lung Metastases

    International Nuclear Information System (INIS)

    Fritz, Peter; Kraus, Hans-Joerg; Muehlnickel, Werner; Sassmann, Volker; Hering, Werner; Strauch, Konstantin

    2010-01-01

    Purpose: To demonstrate the feasibility of complete target immobilization by means of high-frequency jet ventilation (HFJV); and to show that the saving of planning target volume (PTV) on the stereotactic body radiation therapy (SBRT) under HFJV, compared with SBRT with respiratory motion, can be predicted with reliable accuracy by computed tomography (CT) scans at peak inspiration phase. Methods and Materials: A comparison regarding different methods for defining the PTV was carried out in 22 patients with tumors that clearly moved with respiration. A movement span of the gross tumor volume (GTV) was defined by fusing respiration-correlated CT scans. The PTV enclosed the GTV positions with a safety margin throughout the breathing cycle. To create a PTV from CT scans acquired under HFJV, the same margins were drawn around the immobilized target. In addition, peak inspiration phase CT images (PIP-CTs) were used to approximate a target immobilized by HFJV. Results: The resulting HFJV-PTVs were between 11.6% and 45.4% smaller than the baseline values calculated as respiration-correlated CT-PTVs (median volume reduction, 25.4%). Tentative planning by means of PIP-CT PTVs predicted that in 19 of 22 patients, use of HFJV would lead to a reduction in volume of ≥20%. Using this threshold yielded a positive predictive value of 0.89, as well as a sensitivity of 0.94 and a specificity of 0.5. Conclusions: In all patients, SBRT under HFJV provided a reliable immobilization of the GTVs and achieved a reduction in PTVs, regardless of patient compliance. Tentative planning facilitated the selection of patients who could better undergo radiation in respiratory standstill, both with greater accuracy and lung protection.

  16. Dosimetry and irradiation methods for the ANSTO gamma technology research irradiator (GATRI)

    International Nuclear Information System (INIS)

    Izard, M.E.

    1988-07-01

    The Australian Nuclear Science and Technology Organisation's gamma technology research irradiator (GATRI) at Lucas Heights, New South Wales, has been modified for use as a research and small-scale commercial irradiation facility to be available to government agencies and private industry for the technical and economic evaluation of irradiation processing. The new source rack was designed around existing mechanical components to optimise the limited space available within the irradiation cell. Irradiation parameters investigated during commissioning included the effect of source-to-target distance on relative dose rates within targets of the same density; effect of density on dose-rate distribution within targets irradiated at the same distance from the source; and the contribution of transit dose to low absorbed doses as the source is raised and lowered. The efficiency of the irradiator was determined for various target densities and overdose ratios

  17. BAND-9 ALMA OBSERVATIONS OF THE [N II] 122 μm LINE AND FIR CONTINUUM IN TWO HIGH-z GALAXIES

    Energy Technology Data Exchange (ETDEWEB)

    Ferkinhoff, Carl [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Brisbin, Drew; Stacey, Gordon J. [Department of Astronomy, Cornell University, Ithaca, NY 14853 (United States); Nikola, Thomas [Center for Radiophysics and Space Research, Cornell University, Ithaca, NY 14853 (United States); Sheth, Kartik [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States); Hailey-Dunsheath, Steve [California Institute of Technology, Mail Code 301-17, 1200 E. California Blvd., Pasadena, CA 91125 (United States); Falgarone, Edith, E-mail: ferkinhoff@mpia.de [LERMA, CNRS, Observatoire de Paris and ENS (France)

    2015-06-20

    We present Atacama Large Millimeter Array (ALMA) observations of two high-redshift systems (SMMJ02399-0136 at z{sub 1} ∼ 2.8 and the Cloverleaf QSO at z{sub 1} ∼ 2.5) in their rest-frame 122 μm continuum (ν{sub sky} ∼ 650 GHz, λ{sub sky} ∼ 450 μm) and [N ii] 122 μm line emission. The continuum observations with a synthesized beam of ∼0.″ 25 resolve both sources and recover the expected flux. The Cloverleaf is resolved into a partial Einstein ring, while SMMJ02399-0136 is unambiguously separated into two components: a point source associated with an active galactic nucleus and an extended region at the location of a previously identified dusty starburst. We detect the [N ii] line in both systems, though significantly weaker than our previous detections made with the first generation z (Redshift) and Early Universe Spectrometer. We show that this discrepancy is mostly explained if the line flux is resolved out due to significantly more extended emission and longer ALMA baselines than expected. Based on the ALMA observations we determine that ≥75% of the total [N ii] line flux in each source is produced via star formation. We use the [N ii] line flux that is recovered by ALMA to constrain the N/H abundance, ionized gas mass, hydrogen- ionizing photon rate, and star formation rate. In SMMJ02399-0136 we discover it contains a significant amount (∼1000 M{sub ⊙} yr{sup −1}) of unobscured star formation in addition to its dusty starburst and argue that SMMJ02399-0136 may be similar to the Antennae Galaxies (Arp 244) locally. In total these observations provide a new look at two well-studied systems while demonstrating the power and challenges of Band-9 ALMA observations of high-z systems.

  18. Band-9 ALMA Observations of the [N II] 122 μm Line and FIR Continuum in Two High-z galaxies.

    Science.gov (United States)

    Ferkinhoff, Carl; Brisbin, Drew; Nikola, Thomas; Stacey, Gordon J.; Sheth, Kartik; Hailey-Dunsheath, Steve; Falgarone, Edith

    2015-06-01

    We present Atacama Large Millimeter Array (ALMA) observations of two high-redshift systems (SMMJ02399-0136 at z 1 ˜ 2.8 and the Cloverleaf QSO at z 1 ˜ 2.5) in their rest-frame 122 μm continuum (ν sky ˜ 650 GHz, λ sky ˜ 450 μm) and [N ii] 122 μm line emission. The continuum observations with a synthesized beam of ˜0.″ 25 resolve both sources and recover the expected flux. The Cloverleaf is resolved into a partial Einstein ring, while SMMJ02399-0136 is unambiguously separated into two components: a point source associated with an active galactic nucleus and an extended region at the location of a previously identified dusty starburst. We detect the [N ii] line in both systems, though significantly weaker than our previous detections made with the first generation z (Redshift) and Early Universe Spectrometer. We show that this discrepancy is mostly explained if the line flux is resolved out due to significantly more extended emission and longer ALMA baselines than expected. Based on the ALMA observations we determine that ≥75% of the total [N ii] line flux in each source is produced via star formation. We use the [N ii] line flux that is recovered by ALMA to constrain the N/H abundance, ionized gas mass, hydrogen- ionizing photon rate, and star formation rate. In SMMJ02399-0136 we discover it contains a significant amount (˜1000 M ⊙ yr-1) of unobscured star formation in addition to its dusty starburst and argue that SMMJ02399-0136 may be similar to the Antennae Galaxies (Arp 244) locally. In total these observations provide a new look at two well-studied systems while demonstrating the power and challenges of Band-9 ALMA observations of high-z systems.

  19. Materials irradiation research in neutron science

    Energy Technology Data Exchange (ETDEWEB)

    Noda, Kenji; Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-11-01

    Materials irradiation researches are planned in Neutron Science Research Program. A materials irradiation facility has been conceived as one of facilities in the concept of Neutron Science Research Center at JAERI. The neutron irradiation field of the facility is characterized by high flux of spallation neutrons with very wide energy range up to several hundred MeV, good accessibility to the irradiation field, good controllability of irradiation conditions, etc. Extensive use of such a materials irradiation facility is expected for fundamental materials irradiation researches and R and D of nuclear energy systems such as accelerator-driven incineration plant for long-lifetime nuclear waste. In this paper, outline concept of the materials irradiation facility, characteristics of the irradiation field, preliminary technical evaluation of target to generate spallation neutrons, and materials researches expected for Neutron Science Research program are described. (author)

  20. Monte Carlo calculated microdosimetric spread for cell nucleus-sized targets exposed to brachytherapy 125I and 192Ir sources and 60Co cell irradiation.

    Science.gov (United States)

    Villegas, Fernanda; Tilly, Nina; Ahnesjö, Anders

    2013-09-07

    The stochastic nature of ionizing radiation interactions causes a microdosimetric spread in energy depositions for cell or cell nucleus-sized volumes. The magnitude of the spread may be a confounding factor in dose response analysis. The aim of this work is to give values for the microdosimetric spread for a range of doses imparted by (125)I and (192)Ir brachytherapy radionuclides, and for a (60)Co source. An upgraded version of the Monte Carlo code PENELOPE was used to obtain frequency distributions of specific energy for each of these radiation qualities and for four different cell nucleus-sized volumes. The results demonstrate that the magnitude of the microdosimetric spread increases when the target size decreases or when the energy of the radiation quality is reduced. Frequency distributions calculated according to the formalism of Kellerer and Chmelevsky using full convolution of the Monte Carlo calculated single track frequency distributions confirm that at doses exceeding 0.08 Gy for (125)I, 0.1 Gy for (192)Ir, and 0.2 Gy for (60)Co, the resulting distribution can be accurately approximated with a normal distribution. A parameterization of the width of the distribution as a function of dose and target volume of interest is presented as a convenient form for the use in response modelling or similar contexts.

  1. Food irradiation

    International Nuclear Information System (INIS)

    Mercader, J.P.; Emily Leong

    1985-01-01

    The paper discusses the need for effective and efficient technologies in improving the food handling system. It defines the basic premises for the development of food handling. The application of food irradiation technology is briefly discussed. The paper points out key considerations for the adoption of food irradiation technology in the ASEAN region (author)

  2. Food irradiation

    International Nuclear Information System (INIS)

    Matsuyama, Akira

    1990-01-01

    This paper reviews researches, commentaries, and conference and public records of food irradiation, published mainly during the period 1987-1989, focusing on the current conditions of food irradiation that may pose not only scientific or technologic problems but also political issues or consumerism. Approximately 50 kinds of food, although not enough to fill economic benefit, are now permitted for food irradiation in the world. Consumerism is pointed out as the major factor that precludes the feasibility of food irradiation in the world. In the United States, irradiation is feasible only for spices. Food irradiation has already been feasible in France, Hollands, Belgium, and the Soviet Union; has under consideration in the Great Britain, and has been rejected in the West Germany. Although the feasibility of food irradiation is projected to increase gradually in the future, commercial success or failure depends on the final selection of consumers. In this respect, the role of education and public information are stressed. Meat radicidation and recent progress in the method for detecting irradiated food are referred to. (N.K.) 128 refs

  3. Irradiation proctitis

    International Nuclear Information System (INIS)

    Minami, Akira

    1977-01-01

    Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures. (Kanao, N.)

  4. Irradiation proctitis

    Energy Technology Data Exchange (ETDEWEB)

    Minami, A [Osaka Kita Tsishin Hospital (Japan)

    1977-06-01

    Literatures on late rectal injuries are discussed, referring to two patients with uterine cervical cancer in whom irradiation proctitis occurred after telecobalt irradiation following uterine extirpation. To one patients, a total of 5000 rads was irradiated, dividing into 250 rads at one time, and after 3 months, irradiation with a total of 2000 rads, dividing into 200 rads at one time, was further given. In another one patient, two parallel opposing portal irradiation with a total of 6000 rads was given. About a year after the irradiation, rectal injuries and cystitis, accompanying with hemorrhage, were found in both of the patients. Rectal amputation and proctotoreusis were performed. Cystitis was treated by cystic irradiation in the urological department. Pathohistological studies of the rectal specimen revealed atrophic mucosa, and dilatation of the blood vessels and edema in the colonic submucosa. Incidence of this disease, term when the disease occurs, irradiation dose, type of the disease, treatment and prevention are described on the basis of the literatures.

  5. Food irradiation

    International Nuclear Information System (INIS)

    Kobayashi, Yasuhiko; Kikuchi, Masahiro

    2009-01-01

    Food irradiation can have a number of beneficial effects, including prevention of sprouting; control of insects, parasites, pathogenic and spoilage bacteria, moulds and yeasts; and sterilization, which enables commodities to be stored for long periods. It is most unlikely that all these potential applications will prove commercially acceptable; the extend to which such acceptance is eventually achieved will be determined by practical and economic considerations. A review of the available scientific literature indicates that food irradiation is a thoroughly tested food technology. Safety studies have so far shown no deleterious effects. Irradiation will help to ensure a safer and more plentiful food supply by extending shelf-life and by inactivating pests and pathogens. As long as requirement for good manufacturing practice are implemented, food irradiation is safe and effective. Possible risks of food irradiation are not basically different from those resulting from misuse of other processing methods, such as canning, freezing and pasteurization. (author)

  6. Irradiation damage

    Energy Technology Data Exchange (ETDEWEB)

    Howe, L.M

    2000-07-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization.

  7. Irradiation damage

    International Nuclear Information System (INIS)

    Howe, L.M.

    2000-01-01

    There is considerable interest in irradiation effects in intermetallic compounds from both the applied and fundamental aspects. Initially, this interest was associated mainly with nuclear reactor programs but it now extends to the fields of ion-beam modification of metals, behaviour of amorphous materials, ion-beam processing of electronic materials, and ion-beam simulations of various kinds. The field of irradiation damage in intermetallic compounds is rapidly expanding, and no attempt will be made in this chapter to cover all of the various aspects. Instead, attention will be focused on some specific areas and, hopefully, through these, some insight will be given into the physical processes involved, the present state of our knowledge, and the challenge of obtaining more comprehensive understanding in the future. The specific areas that will be covered are: point defects in intermetallic compounds; irradiation-enhanced ordering and irradiation-induced disordering of ordered alloys; irradiation-induced amorphization

  8. Radiochemical Study on the Separation of Chromium-51 from the Irradiated Target by Using Commercial and/or Synthesized Ion Exchanger

    International Nuclear Information System (INIS)

    Aydia, M.I.M.M.

    2012-01-01

    This work involves the following steps:1- Preparation of Triton X-100 Cerium(IV) Phosphate (TX-100CeP) as a surface active ion exchanger or organometallic molecules. 2- Characterization of the TX-100CeP by different methods (i.e. IR, TGA/DTA X-ray diffraction, X-ray fluorescence and elemental analysis). 3- Development a method for separation and quantification of Cr(III) and Cr(VI) by using high pressure liquid chromatography (HPLC). 4- Separation of 51 Cr(III) from Cr(VI) in the target of K 2 CrO 4 on TX-100CeP and Permutit as a commercial ion exchanger. 5- Quality control on the separated 51 Cr(III).

  9. Device for irradiation of a target surface by a variable electron beam, especially electron beam generator, in order to produce semiconductor components

    International Nuclear Information System (INIS)

    Wolfe, J.E.

    1978-01-01

    For the lithographic device there is used a field emission source for thermal ions with a tungsten cathode and a zirconium top as an electron gain. For production of IC chips the electron beam of 1000 A/cm 2 can be focused on a mask template, mounted on a x/Y table, by means of a system of lenses. The electromagnetic focusing device with a small aberration coefficient is designed in such a way that there is obtained a large focal length on the image side as compared to the focal length on the object side. Thereby a small angular deflection of the beam in the focusing device causes a large deflection at the target. The control is performed by a processor. (RW) [de

  10. Ionic Liquid-salt based aqueous biphasic system for quick separation of no-carrier-added 203Pb from proton irradiated natTl2CO3 target

    International Nuclear Information System (INIS)

    Choudhury, Dibyasree; Ghosh, Kaustab; Lahiri, Susanta; Sarkar, Kangkana; Naskar, Nabanita

    2016-01-01

    In the present study, no-carrier-added (NCA) 203 Pb was radiochemically separated from bulk Tl target applying the ABS composing of 4 M K 2 HPO 4 and 0.1 mL of different strengths of IL (bmim)Cl ranging from 40% to 80% (w/v). Bulk Tl was spiked with 200Tl (T 1/2 = 26.1 h). A separation condition was achieved with 70% IL concentration and with 10 min shaking and 10 min settling time, where ∼84% of NCA 203 Pb was extracted into the IL rich phase with ∼10% contamination from bulk Tl. Therefore, further studies, i.e. variation in shaking and settling time were carried out keeping the concentration of IL fixed at 70%

  11. Gas generation during waste treatment of acidic solutions from the dissolution of irradiated LEU targets for 99Mo production

    Energy Technology Data Exchange (ETDEWEB)

    Bakel, Allen J. [Argonne National Lab. (ANL), Argonne, IL (United States); Conner, Cliff [Argonne National Lab. (ANL), Argonne, IL (United States); Quigley, Kevin [Argonne National Lab. (ANL), Argonne, IL (United States); Vandegrift, George F. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-01-01

    The goal of the Reduced Enrichment for Research and Test Reactors Program is to limit the use of high-enriched uranium (HEU) in research and test reactors by substituting low-enriched uranium (LEU) wherever possible. The work reported here documents our work to develop the calcining technologies and processes that will be needed for 99Mo production using LEU foil targets and the Modified Cintichem Process. The primary concern with the conversion to LEU from HEU targets is that it would result in a five- to six-fold increase in the total uranium. This increase results in more liquid waste from the process. We have been working to minimize the increase in liquid waste and to minimize the impact of any change in liquid waste. Direct calcination of uranium-rich nitric acid solutions generates NO2 gas and UO3 solid. We have proposed two processes for treating the liquid waste from a Modified Cintichem Process with a LEU foil. One is an optimized direct calcination process that is similar to the process currently in use. The other is a uranyl oxalate precipitation process. The specific goal of the work reported here was to characterize and compare the chemical reactions that occur during these two processes. In particular, the amounts and compositions of the gaseous and solid products were of interest. A series of experiments was carried out to show the effects of temperature and the redox potential of the reaction atmosphere. The primary products of the direct calcination process were mixtures of U3O8 and UO3 solids and NO2 gas. The primary products of the oxalate precipitation process were mixtures of U3O8 and UO2 solid and CO2 gas. Higher temperature and a reducing atmosphere tended to favor quadrivalent over hexavalent uranium in the solid product. These data will help producers to decide between the two processes. In addition, the data can be used

  12. The ISOLDE target robots

    CERN Multimedia

    Maximilein Brice

    2002-01-01

    ISOLDE targets need to be changed frequently, around 80 times per year. The high radiation levels do not permit this to be done by human hands and the target changes are effected by 2 industrial robots (picture _01). On the left, in the distance, the front-end of the GPS (General Purpose Separator) is seen, while the HRS (High Resolution Separator) is at the right. Also seen are the doors to the irradiated-target storage.

  13. About Influence of Ionic Beams of Metals of IVB-VIB Groups on Structure and Properties of a Target at Various Modes of Irradiation

    Science.gov (United States)

    Kurbatova, E. I.; Klimanov, V. A.; Ksenofontov, A. I.; Fridlyander, I. N.

    2006-08-01

    A complex of special properties of materials and a threshold of their working temperatures which is frequently limited 500-550°C define the level of modern technological development and, first of all, for nuclear-industrial plants. The alloys on the basis of iron are the most widespread kind of constructional materials, and therefore an increase of their special properties (high-temperature strength, corrosion stability, durability and other characteristics) is of great value. The ionic beams with a low energy (300-1,500 eV) which can change the structure and the properties of a target, in particular iron and its alloys were used for the solution of these problems in the present work. In this work theoretical and experimental results of the research of the process of impact interaction of the ionic beams with iron are also given. The properties of a iron surface with the help of modern methods of physical and chemical analyse are investigated. The opportunities to produce new surface properties of iron using the ionic beams are shown. On the basis of the results obtained the supplementary work directions are analyzed.

  14. Food irradiation

    International Nuclear Information System (INIS)

    Hetherington, M.

    1989-01-01

    This popular-level article emphasizes that the ultimate health effects of irradiated food products are unknown. They may include vitamin loss, contamination of food by botulism bacteria, mutations in bacteria, increased production of aflatoxins, changes in food, carcinogenesis from unknown causes, presence of miscellaneous harmful chemicals, and the lack of a way of for a consumer to detect irradiated food. It is claimed that the nuclear industry is applying pressure on the Canadian government to relax labeling requirements on packages of irradiated food in order to find a market for its otherwise unnecessary products

  15. Food irradiation

    International Nuclear Information System (INIS)

    Luecher, O.

    1979-01-01

    Limitations of existing preserving methods and possibilities of improved food preservation by application of nuclear energy are explained. The latest state-of-the-art in irradiation technology in individual countries is described and corresponding recommendations of FAO, WHO and IAEA specialists are presented. The Sulzer irradiation equipment for potato sprout blocking is described, the same equipment being suitable also for the treatment of onions, garlic, rice, maize and other cereals. Systems with a higher power degree are needed for fodder preserving irradiation. (author)

  16. Development of the 2nd generation z(Redshift) and early universe spectrometer & the study of far-IR fine structure emission in high-z galaxies

    Science.gov (United States)

    Ferkinhoff, Carl

    The 2nd generation z (Redshift) and Early Universe Spectrometer (ZEUS-2), is a long-slit echelle-grating spectrometer (R~1000) for observations at submillimeter wavelengths from 200 to 850 microm. Its design is optimized for the detection of redshifted far-infrared spectral lines from galaxies in the early universe. Combining exquisite sensitivity, broad wavelength coverage, and large (˜2.5%) instantaneous bandwidth, ZEUS-2 is uniquely suited for studying galaxies between z˜0.2 and 5---spanning the peaks in both the star formation rate and number of AGN in the universe. ZEUS-2 saw first light at the Caltech Submillimeter Observatory (CSO) in the Spring of 2012 and was commissioned on the Atacama Pathfinder Experiment (APEX) in November 2012. Here we detail the design and performance of ZEUS-2, first however we discuss important science results that are examples of the science enabled by ZEUS-2. Using the first generation z (Redshift) and Early Universe Spectrometer (ZEUS-1) we made the first high-z detections of the [NII] 122 microm and [OIII] 88 microm lines. We detect these lines from starburst galaxies between z ˜2.5 and 4 demonstrating the utility of these lines for characterizing the properties of early galaxies. Specifically we are able to determine the most massive star still on the main sequence, the number of those stars and a lower limit on the mass of ionized gas in the source. Next we present ZEUS-2's first science result. Using ZEUS-2 on APEX we have detected the [CII] 158 microm line from the z = 1.78 galaxy H-ATLAS J091043.1-000322 with a line flux of (6.44 +/- 0.42) ˜ 10-18 W m-2. Combined with its far-infrared luminosity and a new Herschel-PACS detection of the [OI] 63 microm line we are able to conclude that H-ATLAS J091043.1-000322 is a high redshift analogue of a local ultra-luminous infrared galaxy, i.e. it is likely the site of a compact starburst due to a major merger. This detection, combined with the ZEUS-1 observations of the [NII

  17. Improvement of high T{sub c} superconductor by near-optimum pinning centers created by high Z, high-energy ions

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Roy, E-mail: Weinstein@uh.edu [Texas Center for Superconductivity, Physics Department, 632 Science and Research Bldg. 1, University of Houston, Houston, TX 77204-5005 (United States); Sawh, Ravi-Persad; Parks, Drew; Mayes, Billy [Texas Center for Superconductivity, Physics Department, 632 Science and Research Bldg. 1, University of Houston, Houston, TX 77204-5005 (United States)

    2012-02-01

    Damage tracks left by high Z, high-energy ions in high temperature superconductor (HTS) can serve the need to pin in place the magnetic field quanta. Such pinning centers (PCs) can serve to dramatically increase the critical current density, J{sub c}. Specific energy loss, S{sub e}, which is effective in the YBCO superconductor (YBa{sub 2}Cu{sub 3}O{sub 7-{delta}}) lies in the range 0.7 Less-Than-Or-Slanted-Equal-To S{sub e} Less-Than-Or-Slanted-Equal-To 3.5 keV/A. At 77 K, a sharp peak in J{sub c} occurs at S{sub e} {approx} 2.1 keV/A, for fluences of 10{sup 12} ions/cm{sup 2}, where record in-field J{sub c} is achieved in large-grain YBCO. For example, J{sub c} = 340 kA/cm{sup 2} at 77 K, applied field of 1 T. At closely similar conditions record in-field J{sub c} is achieved in thick coated conductor, e.g., J{sub c} = 543 kA/cm{sup 2} at 77 K, 1 T. When corrected to the optimum S{sub e}, this J{sub c} increases to 770 kA/cm{sup 2}. These near-optimum PCs have very small diameter of damage (d{sub d} {approx} 6.6 nm) close to the value, predicted theoretically. However, they are very discontinuous, whereas theory predicts that continuous columnar PCs are the best to obtain high J{sub c}. We find that the advantages of discontinuous PCs at S{sub e} = 2.1 keV/A, are (a) a factor of 12 less damage to the HTS (resulting in improved percolation and T{sub c}) and (b) entanglement of fluxoids (even for parallel PCs). This results in five times higher J{sub c} than can be achieved with continuous columnar PCs. In large-grain HTS, these pinning centers increase J{sub c} by a factor of 17, indicating that the dominant reduction of J{sub c} in large-grain HTS is due not to weak links, voids, non-optimum oxygenation, etc., but to a dearth of pinning centers.

  18. Food irradiation

    International Nuclear Information System (INIS)

    Paganini, M.C.

    1991-06-01

    Food treatment by means of ionizing energy, or irradiation, is an innovative method for its preservation. In order to treat important volumes of food, it is necessary to have industrial irradiation installations. The effect of radiations on food is analyzed in the present special work and a calculus scheme for an Irradiation Plant is proposed, discussing different aspects related to its project and design: ionizing radiation sources, adequate civil work, security and auxiliary systems to the installations, dosimetric methods and financing evaluation methods of the project. Finally, the conceptual design and calculus of an irradiation industrial plant of tubercles is made, based on the actual needs of a specific agricultural zone of our country. (Author) [es

  19. Food irradiation

    International Nuclear Information System (INIS)

    Anon.

    1984-01-01

    Food preservation by irradiation is one part of Eisenhower's Atoms for Peace program that is enjoying renewed interest. Classified as a food additive by the Food, Drug, and Cosmetic Act of 1958 instead of a processing technique, irradiation lost public acceptance. Experiments have not been done to prove that there are no health hazards from gamma radiation, but there are new pressures to get Food and Drug Administration approval for testing in order to make commercial use of some radioactive wastes. Irradiation causes chemical reactions and nutritional changes, including the destruction of several vitamins, as well as the production of radiolytic products not normally found in food that could have adverse effects. The author concludes that, lacking epidemiological evidence, willing buyers should be able to purchase irradiated food as long as it is properly labeled

  20. Fruit irradiation

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Food spoilage is a common problem when marketing agricultural products. Promising results have already been obtained on a number of food irradiating applications. A process is described in this paper where irradiation of sub-tropical fruits, especially mangoes and papayas, combined with conventional heat treatment results in effective insect and fungal control, delays ripening and greatly improves the quality of fruit at both export and internal markets

  1. Tissue irradiator

    International Nuclear Information System (INIS)

    Hungate, F.P.; Riemath, W.F.; Bunnell, L.R.

    1975-01-01

    A tissue irradiator is provided for the in-vivo irradiation of body tissue. The irradiator comprises a radiation source material contained and completely encapsulated within vitreous carbon. An embodiment for use as an in-vivo blood irradiator comprises a cylindrical body having an axial bore therethrough. A radioisotope is contained within a first portion of vitreous carbon cylindrically surrounding the axial bore, and a containment portion of vitreous carbon surrounds the radioisotope containing portion, the two portions of vitreous carbon being integrally formed as a single unit. Connecting means are provided at each end of the cylindrical body to permit connections to blood-carrying vessels and to provide for passage of blood through the bore. In a preferred embodiment, the radioisotope is thulium-170 which is present in the irradiator in the form of thulium oxide. A method of producing the preferred blood irradiator is also provided, whereby nonradioactive thulium-169 is dispersed within a polyfurfuryl alcohol resin which is carbonized and fired to form the integral vitreous carbon body and the device is activated by neutron bombardment of the thulium-169 to produce the beta-emitting thulium-170

  2. Blood irradiation

    International Nuclear Information System (INIS)

    Chandy, Mammen

    1998-01-01

    Viable lymphocytes are present in blood and cellular blood components used for transfusion. If the patient who receives a blood transfusion is immunocompetent these lymphocytes are destroyed immediately. However if the patient is immunodefficient or immunosuppressed the transfused lymphocytes survive, recognize the recipient as foreign and react producing a devastating and most often fatal syndrome of transfusion graft versus host disease [T-GVHD]. Even immunocompetent individuals can develop T-GVHD if the donor is a first degree relative since like the Trojan horse the transfused lymphocytes escape detection by the recipient's immune system, multiply and attack recipient tissues. T-GVHD can be prevented by irradiating the blood and different centers use doses ranging from 1.5 to 4.5 Gy. All transfusions where the donor is a first degree relative and transfusions to neonates, immunosuppressed patients and bone marrow transplant recipients need to be irradiated. Commercial irradiators specifically designed for irradiation of blood and cellular blood components are available: however they are expensive. India needs to have blood irradiation facilities available in all large tertiary institutions where immunosuppressed patients are treated. The Atomic Energy Commission of India needs to develop a blood irradiator which meets international standards for use in tertiary medical institutions in the country. (author)

  3. Food irradiation

    International Nuclear Information System (INIS)

    Migdal, W.

    1995-01-01

    A worldwide standard on food irradiation was adopted in 1983 by codex Alimentarius Commission of the Joint Food Standard Programme of the Food and Agriculture Organization (FAO) of the United Nations and The World Health Organization (WHO). As a result, 41 countries have approved the use of irradiation for treating one or more food items and the number is increasing. Generally, irradiation is used to: food loses, food spoilage, disinfestation, safety and hygiene. The number of countries which use irradiation for processing food for commercial purposes has been increasing steadily from 19 in 1987 to 33 today. In the frames of the national programme on the application of irradiation for food preservation and hygienization an experimental plant for electron beam processing has been established in Inst. of Nuclear Chemistry and Technology. The plant is equipped with a small research accelerator Pilot (19 MeV, 1 kW) and industrial unit Electronika (10 MeV, 10 kW). On the basis of the research there were performed at different scientific institutions in Poland, health authorities have issued permissions for irradiation for; spices, garlic, onions, mushrooms, potatoes, dry mushrooms and vegetables. (author)

  4. Food irradiation

    International Nuclear Information System (INIS)

    1991-01-01

    Processing of food with low levels of radiation has the potential to contribute to reducing both spoilage of food during storage - a particular problem in developing countries - and the high incidence of food-borne disease currently seen in all countries. Approval has been granted for the treatment of more than 30 products with radiation in over 30 countries but, in general, governments have been slow to authorize the use of this new technique. One reason for this slowness is a lack of understanding of what food irradiation entails. This book aims to increase understanding by providing information on the process of food irradiation in simple, non-technical language. It describes the effects that irradiation has on food, and the plant and equipment that are necessary to carry it out safely. The legislation and control mechanisms required to ensure the safety of food irradiation facilities are also discussed. Education is seen as the key to gaining the confidence of the consumers in the safety of irradiated food, and to promoting understanding of the benefits that irradiation can provide. (orig.) With 4 figs., 1 tab [de

  5. Measurement of the high-energy neutron flux on the surface of the natural uranium target assembly QUINTA irradiated by deuterons of 4- and 8-GeV energy

    International Nuclear Information System (INIS)

    Adam, J.; Baldin, A.A.; Chilap, V.

    2014-01-01

    Experiments with a natural uranium target assembly QUINTA exposed to 4- and 8 GeV deuteron beams of the Nuclotron accelerator at the Joint Institute for Nuclear Research (Dubna) are analyzed. The 129 I, 232 Th, 233 U, 235 U, nat U, 237 Np, 238 Pu, 239 Pu and 241 Am radioactive samples were installed on the surface of the QUINTA set-up and irradiated with secondary neutrons. The neutron flux through the RA samples was monitored by Al foils. The reaction rates of 27 Al(n, y 1 ) 24 Na, 27 Al(n, y 2 ) 22 Na and 27 Al(n, y 3 ) 7 Be reactions with the effective threshold energies of 5, 27 and 119 MeV were measured at both 4- and 8-GeV deuteron beam energies. The average neutron fluxes between the effective threshold energies and the effective ends of the neutron spectra (which are 800 or 1000 MeV for energy of 4- or 8-GeV deuterons) were determined. The evidence for the intensity shift of the neutron spectra to higher neutron energies with the increase of the deuteron energy from 4 to 8 GeV was found from the ratios of the average neutron fluxes. The reaction rates and the average neutron fluxes were calculated with MCNPX2.7 and MARS15 codes.

  6. Targets for heavy ion fusion

    International Nuclear Information System (INIS)

    Clauser, M.J.

    1978-01-01

    This paper describes some of the basic principles of fusion target implosions, using some simple targets designed for irradiation by ion beams. Present estimates are that ion beams with 1-5 MJ, and 100-500 TW will be required to ignite high gain targets. (orig.) [de

  7. Nuclear prehistory influence on irradiated metallic iron phase composition

    International Nuclear Information System (INIS)

    Alekseev, I.E.

    2007-01-01

    With application of different Moessbauer spectroscopy applications the phase composition of metallic iron after irradiation by both neutrons and charged particles were studied. Irradiation conditions, method of targets examination and phase composition of samples after irradiation were presented in tabular form. It is shown, that phase composition of irradiated metal is defined by nuclear prehistory. So, in a number of cases abnormals (stabilization of high- and low-temperature structural phases of iron at room temperature after irradiation end) were revealed

  8. Irradiation device

    International Nuclear Information System (INIS)

    Suzuki, Toshimitsu.

    1989-01-01

    In an irradiation device for irradiating radiation rays such as electron beams to pharmaceuticals, etc., since the distribution of scanned electron rays was not monitored, the electron beam intensity could be determined only indirectly and irradiation reliability was not satisfactory. In view of the above, a plurality of monitor wires emitting secondary electrons are disposed in the scanning direction near a beam take-out window of a scanning duct, signals from the monitor wires are inputted into a display device such as a cathode ray tube, as well as signals from the monitor wires at the central portion are inputted into counting rate meters to measure the radiation dose as well. Since secondary electrons are emitted when electron beams pass through the monitor wires and the intensity thereof is in proportion with the intensity of incident electron beams, the distribution of the radiation dose can be monitored by measuring the intensity of the emitted secondary electrons. Further, uneven irradiation, etc. can also be monitored to make the radiation of irradiation rays reliable. (N.H.)

  9. Food irradiation

    International Nuclear Information System (INIS)

    Beishon, J.

    1991-01-01

    Food irradiation has been the subject of concern and controversy for many years. The advantages of food irradiation include the reduction or elimination of dangerous bacterial organisms, the control of pests and insects which destroy certain foods, the extension of the shelf-life of many products, for example fruit, and its ability to treat products such as seafood which may be eaten raw. It can also replace existing methods of treatment which are believed to have hazardous side-effects. However, after examining the evidence produced by the proponents of food irradiation, the author questions whether it has any major contribution to make to the problems of foodborne diseases or world food shortages. More acceptable solutions, he suggests, may be found in educating food handlers to ensure that hygienic conditions prevail in the production, storage and serving of food. (author)

  10. Vinca irradiator

    International Nuclear Information System (INIS)

    Eymery, R.

    1976-10-01

    The development programme of the VINCA radiosterilisation centre involves plans for an irradiator capable of working in several ways. Discontinuous operation. The irradiator is loaded for a certain period then runs automatically until the moment of unloading. This method is suitable as long as the treatment capacity is relatively small. Continuous operation with permanent batch loading and unloading carried out either manually or automatically (by means of equipment to be installed later). Otherwise the design of the apparatus is highly conventional. The source is a vertical panel submersible in a pool. The conveyor is of the 'bucket' type, with 4 tiers to each bucket. The batches pass successively through all possible irradiation positions. Transfert into and out of the cell take place through a maze, which also provides access to the cell when the sources are in storage at the bottom of the pool [fr

  11. Irradiance gradients

    International Nuclear Information System (INIS)

    Ward, G.J.; Heckbert, P.S.; Technische Hogeschool Delft

    1992-04-01

    A new method for improving the accuracy of a diffuse interreflection calculation is introduced in a ray tracing context. The information from a hemispherical sampling of the luminous environment is interpreted in a new way to predict the change in irradiance as a function of position and surface orientation. The additional computation involved is modest and the benefit is substantial. An improved interpolation of irradiance resulting from the gradient calculation produces smoother, more accurate renderings. This result is achieved through better utilization of ray samples rather than additional samples or alternate sampling strategies. Thus, the technique is applicable to a variety of global illumination algorithms that use hemicubes or Monte Carlo sampling techniques

  12. Performance of Shiva as a laser fusion irradiation facility

    International Nuclear Information System (INIS)

    Speck, D.R.; Bliss, E.S.; Glaze, J.A.; Johnson, B.C.; Manes, K.R.; Ozarski, R.G.; Rupert, P.R.; Simmons, W.W.; Swift, C.D.; Thompson, C.E.

    1979-01-01

    Shiva is a 20 beam Nd:Glass Laser and Target Irradiation Facility at the Lawrence Livermore Laboratory. The laser system and integrated target facility evolved during the last year from a large, untested, experimental laser system to a target irradiation facility which has provided significant laser driven inertial confinement fusion data. The operation of the facility is discussed

  13. Investigation of in vivo PIXE effect within superficial tumor model of high-Z metalnanoplatform for PIXE-based proton therapy

    International Nuclear Information System (INIS)

    Kim, Jong Ki; Seo, Seung Jun; Lee, Ju Hong

    2010-04-01

    Metallic nanoparticles (MNP) are able to release localized X-ray when activated with high energy proton beam by particle induced X-ray emissions (PIXE) effect. The exploitation of this phenomenon in the therapeutic irradiation of tumors has been investigated. PIXE-based X-ray emission directed at CT-26 tumor cells in vitro, when administered with either gold (average diameter, 2 nm and 13 nm) or iron (average diameter, 14 nm) nanoparticles, increased with MNP solution concentration over the range of 0.1-2 mg/mL. With irradiation by 45-MeV proton therapy (PT) beam, higher concentrations had a decreased cell survival fraction. An in vivo study with tumor regression assay demonstrated significant tumor dose enhancement, thought to be result of the PIXE effect when compared to conventional PT without MNP using a 45 MeV proton beam (p<0.01). These effects were observed for gold and iron MNP, injected in doses of 100-300mg/kg body weight into CT-26 mouse tumor models via tail vein. A therapeutic effective MNP concentration range, in vivo,was estimated at 30-79 μg/g tissue for both gold and iron nanoparticles. The tumor dose enhancement may compensate for an increase in entrance dose associated with conventional PT when treating large, solid tumors with a spread out Bragg peak (SOBP) technique. The use of combined high energy Bragg peak PT with PIXE generated by MNP, or PIXE alone may result in new treatment options for infiltrative metastatic tumors and other diffuse inflammatory diseases

  14. Genomic instability following irradiation

    International Nuclear Information System (INIS)

    Hacker-Klom, U.B.; Goehde, W.

    2001-01-01

    Ionising irradiation may induce genomic instability. The broad spectrum of stress reactions in eukaryontic cells to irradiation complicates the discovery of cellular targets and pathways inducing genomic instability. Irradiation may initiate genomic instability by deletion of genes controlling stability, by induction of genes stimulating instability and/or by activating endogeneous cellular viruses. Alternatively or additionally it is discussed that the initiation of genomic instability may be a consequence of radiation or other agents independently of DNA damage implying non nuclear targets, e.g. signal cascades. As a further mechanism possibly involved our own results may suggest radiation-induced changes in chromatin structure. Once initiated the process of genomic instability probably is perpetuated by endogeneous processes necessary for proliferation. Genomic instability may be a cause or a consequence of the neoplastic phenotype. As a conclusion from the data available up to now a new interpretation of low level radiation effects for radiation protection and in radiotherapy appears useful. The detection of the molecular mechanisms of genomic instability will be important in this context and may contribute to a better understanding of phenomenons occurring at low doses <10 cSv which are not well understood up to now. (orig.)

  15. Studies on the separation of {sup 89}Sr(II) from irradiated yttria target using 4, 4{sup '}(5{sup '}) di-tert-butyl-cyclohexano-18-crown-6 (DtBuCH18C6) by solvent extraction technique

    Energy Technology Data Exchange (ETDEWEB)

    Saha, Debasish; Vithya, Jayagopal; Kumar, Ramalingam; Venkata Subramani, Canchipuram Ramamoorthy; Vasudeva Rao, Polur Ranga [Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam (India). Chemistry Group

    2016-07-01

    The radioisotope {sup 89}Sr as {sup 89}SrCl{sub 2} is medically useful for bone pain palliation and is produced in fast reactors using the {sup 89}Y(n, p){sup 89}Sr reaction. A procedure for isolation of the radionuclide {sup 89}Sr by chemical processing of the irradiated Y{sub 2}O{sub 3} target has been standardised and trial runs have been carried out at the Fast Breeder Test Reactor (FBTR), Kalpakkam. The chemical processing of the irradiated Y{sub 2}O{sub 3} target involves (i) the removal of target Y(III) by TBP extraction and (ii) further purification of the separated {sup 89}Sr fraction by cationic exchange chromatography. However a selective isolation of {sup 89}Sr by the Sr-specific crown ether makes the above chemical processing faster and relatively simple. This work presents a study on the selective removal of Sr from the irradiated target dissolver solution using the Sr-specific crown ether 4,4{sup '}(5{sup '}) di-tert-butyl-cyclohexano-18-crown-6 (DtBuCH18C6) in octanol medium. The separation behaviour of the other impurities such as Ce(IV), Y(III), Tb(III), Eu(III), Zn(II), Mn(II) and Rb(I) present along with Sr(II) in the irradiated sample was also investigated. The method of separation by using the crown ether DtBuCH18C6 is proved to be a potential tool for the purification of {sup 89}Sr(II) source produced from yttria target in fast reactors.

  16. Irradiation as Quarantine Treatment of Rambutan

    International Nuclear Information System (INIS)

    Pransopon, Prapon; Kongratarpon, Titima; Vongchili, Satit; Segsarnviriya, Suchada; Limohpasmanee, Wanith; Eamsiri, Jarurat; Sajjabut, Surasak

    2006-01-01

    Eggs and larvae of Bactrocera dorsalis and Bactrocera correcta were investigated for their tolerant dose of irradiation. Artificially in feasted rambutans were irradiated at target doses of 0, 10, 20, 30, 40, 50 and 60 Gy. The results showed that the lowest dose that could inhibit adult emergence was 102.89 Gy for B. dorsalis and 97.61 Gy for B. correcta (P=0.999968, Probit 9). Larvae of B. dorsalis were irradiated at the dose

  17. ion irradiation

    Indian Academy of Sciences (India)

    Swift heavy ions interact predominantly through inelastic scattering while traversing any polymer medium and produce excited/ionized atoms. Here samples of the polycarbonate Makrofol of approximate thickness 20 m, spin coated on GaAs substrate were irradiated with 50 MeV Li ion (+3 charge state). Build-in ...

  18. Simulations of tungsten, tungsten-coated and tungsten-doped targets at low KrF laser intensities

    Science.gov (United States)

    Colombant, D.; Klapisch, M.; Lehecka, T.; Seely, J.; Schmitt, A.; Obenschain, S.

    1998-11-01

    High-Z coatings can be used to create X-rays to preheat the ablator, thus reducing the laser imprint and the R-T instability. Targets with tungsten coated on the surface or mixed with CH have recently been irradiated using Nike at intensities of a few 10^12W/cm^2, typical of the foot of a laser fusion pulse. The present simulations in 1D have been carried out to provide an interpretation of these experiments and to validate the code for radiation-preheated target designs(S. E. Bodner et al., Phys. Plasmas, 5, 1901 (1998).). All computations were performed in non-LTE(M. Busquet, Phys. Fluids B, 5, 4191 (1993); M. Klapisch, A. Bar-Shalom, J. Oreg and D. Colombant, Phys. Plasmas, 5, 1919 (1998).). Low resolution X-ray spectra obtained from on-line computations are compared to time-integrated experimental spectra between 100 eV and 500 eV. Agreements and differences between computations and experiments will be discussed.

  19. The effect of carbon impurities on molybdenum surface morphology evolution under high-flux low-energy helium ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, J.K., E-mail: jtripat@purdue.edu; Novakowski, T.J.; Gonderman, S.; Bharadwaj, N.; Hassanein, A.

    2016-09-15

    We report on the role of carbon (C) impurities, in molybdenum (Mo) fuzz evolutions on Mo surface during 100 eV He{sup +} ion irradiations. In this study we considered 0.01, 0.05, and 0.5% C{sup +} ion impurities in He{sup +} ion irradiations. For introducing such tiny C{sup +} ion impurities, gas mixtures of He and CH{sub 4} have been chosen in following ratios; 99.95: 0.05, 99.75: 0.25, and 97.5: 2.5. Apart from these three cases, two additional cases, 100% He{sup +} ion (for Mo fuzz growth due to only He{sup +} ions) and 100% H{sup +} ion (for confirming the significance of tiny 0.04–2.0% H{sup +} ions in terms of Mo fuzz evolutions on Mo surface, if any), have also been considered. Ion energy (100 eV), ion fluence (2.6 × 10{sup 24} ions m{sup −2}), and target temperature (923 K) were kept constant for each experiment and their selections were based on our previous studies [1,2]. Our study shows homogeneously populated and highly dense Mo fuzz evolutions on entire Mo surface for 100% He{sup +} ion irradiation case. Enhancement of C{sup +} ion impurities in He{sup +} ions causes a sequential reduction in Mo fuzz evolutions, leading to almost complete prevention of Mo fuzz evolutions for 0.5% C{sup +} ion impurity concentrations. Additionally, no fuzz formation for 100% H{sup +} ion irradiation at all, were seen (apart from some tiny nano-structuring, in very limited regions). This indicates that there is no significant role of H{sup +} ions in Mo fuzz evolutions (at least for such tiny amount, 0.04–2.0% H{sup +} ions). The study is significant to understand the behavior of potential high-Z plasma facing components (PFCs), in the, presence of tiny amount of C impurities, for nuclear fusion relevant applications. - Highlights: • Mo Fuzz evolutions due to low-energy high-flux 100% He{sup +} ion irradiation. • Sequential reduction in Mo fuzz evolutions with increasing C{sup +} ion impurities in He{sup +} ions. • Almost complete prevention of Mo

  20. Fish irradiation

    International Nuclear Information System (INIS)

    Kovacs, J.; Tengumnuay, C.; Juangbhanich, C.

    1970-01-01

    Chub-mackerel was chosen for the study because they are the most common fish in Thailand. Preliminary investigations were conducted to determine the maximum radiation dose of gamma-rays by organoleptic tests. The samples were subjected to radiation at various doses up to 4 Mrad. Many experiments were conducted using other kinds of fish. The results showed that 1 Mrad would be the maximum acceptable dose for fish. Later, the influence of the radiation dose from 0.1-1 Mrad was studied in order to find the optimum acceptable dose for preservation of fish without off-flavour. For this purpose, the Hedonic scale was used. It was found that 0.2 and 0.5 Mrad gave the best result on Chub mackerel. The determinations of optimum dose, organoleptic, microbiological and trimethylamine content changes were done. The results showed that Chub mackerel irradiated at 0.2, 0.5 and 1 Mrad stored at 3 0 C for 71 days were still acceptable, on the contrary the untreated samples were found unacceptable at 14 days. The trimethylamine increment was significantly higher in the untreated samples. At 15 days storage, trimethylamine in the non-irradiated Chub-mackerel was about 10 times higher than the irradiated ones. At 51 and 79 days storage, about 13 times higher in the control samples than the irradiated samples except 0.1 Mrad. Only 2 times higher was found for the 0.1 Mrad. The microbiological results showed that the irradiation above 0.2 Mrad gave favorable extension of shelf-life of fish

  1. Chapter 2: Irradiators

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2018-04-01

    The chapter 2 presents the subjects: 1) gamma irradiators which includes: Category-I gamma irradiators (self-contained); Category-II gamma irradiators (panoramic and dry storage); Category-III gamma irradiators (self-contained in water); Category-IV gamma irradiators (panoramic and wet storage); source rack for Category-IV gamma irradiators; product transport system for Category-IV gamma irradiators; radiation shield for gamma irradiators; 2) accelerators which includes: Category-I Accelerators (shielded irradiator); Category-II Accelerators (irradiator inside a shielded room); Irradiation application examples.

  2. Coherent structures in ablatively compressed ICF targets and Rayleigh-Taylor instability

    International Nuclear Information System (INIS)

    Pant, H.C.; Desai, T.

    1996-01-01

    One of the major issues in laser induced inertial confinement fusion (ICF) is a stable ablative compression of spherical fusion pellets. The main impediment in achievement of this objective is Rayleigh-Taylor instability at the pellet's ablation front. Under sufficiently high acceleration this instability can grow out of noise. However, it can also arise either due to non-uniform laser intensity distribution over the pellet surface or due to pellet wall areal mass irregularity. Coherent structures in the dense target behind the ablation front can be effectively utilised for stabilisation of the Rayleigh-Taylor phenomenon. Such coherent structures in the form of a super lattice can be created by doping the pellet pusher with high atomic number (Z) micro particles. A compressed-cool pusher under laser irradiation behaves like a strongly correlated non ideal plasma when compressed to sufficiently high density such that the non ideality parameter exceeds unity. Moreover, the nonideality parameter for high Z microinclusions may exceed a critical value of 180 and as a consequence they remain in the form of intact clusters, maintaining the superlattice intact during ablative acceleration. Micro-hetrogeneity and its superlattice plays an important role in stabilization of Rayleigh-Taylor instability, through a variety of mechanisms. (orig.)

  3. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy.

    Science.gov (United States)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-09

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR (192)Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR (192)Ir brachytherapy.

  4. Intensity Modulated Radiotherapy Improves Target Coverage and Parotid Gland Sparing When Delivering Total Mucosal Irradiation in Patients With Squamous Cell Carcinoma of Head and Neck of Unknown Primary Site

    International Nuclear Information System (INIS)

    Bhide, Shreerang; Clark, Catherine; Harrington, Kevin; Nutting, Christopher M.

    2007-01-01

    Head and neck squamous cell carcinoma with occult primary site represents a controversial clinical problem. Conventional total mucosal irradiation (TMI) maximizes local control, but at the expense of xerostomia. IMRT has been shown to spare salivary tissue in head and cancer patients. This study has been performed to investigate the potential of IMRT to perform nodal and TMI and also allow parotid gland sparing in this patient group. Conventional radiotherapy (CRT) and IMRT plans were produced for six patients to treat the ipsilateral (involved) post-operative neck (PTV1) and the un-operated contralateral neck and mucosal axis (PTV2). Plans were produced with and without the inclusion of nasopharynx in the PTV2. The potential to improve target coverage and spare the parotid glands was investigated for the IMRT plans. There was no significant difference in the mean doses to the PTV1 using CRT and IMRT (59.7 and 60.0 respectively, p = 0.5). The maximum doses to PTV1 and PTV2 were lower for the IMRT technique as compared to CRT (P = 0.008 and P < 0.0001), respectively, and the minimum doses to PTV1 and PTV2 were significantly higher for IMRT as compared to CRT (P = 0.001 and P = 0.001), respectively, illustrating better dose homogeneity with IMRT. The mean dose to the parotid gland contralateral to PTV1 was significantly lower for IMRT (23.21 ± 0.7) as compared to CRT (50.5 ± 5.8) (P < 0.0001). There was a significant difference in parotid dose between plans with and without the inclusion of the nasopharynx. IMRT offers improved dose homogeneity in PTV1 and PTV2 and allows for parotid sparing

  5. Attenuation measurements show that the presence of a TachoSil surgical patch will not compromise target irradiation in intra-operative electron radiation therapy or high-dose-rate brachytherapy

    International Nuclear Information System (INIS)

    Sarmento, Sandra; Costa, Filipa; Pereira, Alexandre; Lencart, Joana; Dias, Anabela; Cunha, Luís; Sousa, Olga; Silva, José Pedro; Santos, Lúcio

    2015-01-01

    Surgery of locally advanced and/or recurrent rectal cancer can be complemented with intra-operative electron radiation therapy (IOERT) to deliver a single dose of radiation directly to the unresectable margins, while sparing nearby sensitive organs/structures. Haemorrhages may occur and can affect the dose distribution, leading to an incorrect target irradiation. The TachoSil (TS) surgical patch, when activated, creates a fibrin clot at the surgical site to achieve haemostasis. The aim of this work was to determine the effect of TS on the dose distribution, and ascertain whether it could be used in combination with IOERT. This characterization was extended to include high dose rate (HDR) intraoperative brachytherapy, which is sometimes used at other institutions instead of IOERT. CT images of the TS patch were acquired for initial characterization. Dosimetric measurements were performed in a water tank phantom, using a conventional LINAC with a hard-docking system of cylindrical applicators. Percentage Depth Dose (PDD) curves were obtained, and measurements made at the depth of dose maximum for the three clinically used electron energies (6, 9 and 12MeV), first without any attenuator and then with the activated patch of TS completely covering the tip of the IOERT applicator. For HDR brachytherapy, a measurement setup was improvised using a solid water phantom and a Farmer ionization chamber. Our measurements show that the attenuation of a TachoSil patch is negligible, both for high energy electron beams (6 to 12MeV), and for a HDR 192 Ir brachytherapy source. Our results cannot be extrapolated to lower beam energies such as 50 kVp X-rays, which are sometimes used for breast IORT. The TachoSil surgical patch can be used in IORT procedures using 6MeV electron energies or higher, or HDR 192 Ir brachytherapy

  6. Heavy ion irradiation induces autophagy in irradiated C2C12 myoblasts and their bystander cells

    International Nuclear Information System (INIS)

    Hino, Mizuki; Tajika, Yuki; Hamada, Nobuyuki

    2010-01-01

    Autophagy is one of the major processes involved in the degradation of intracellular materials. Here, we examined the potential impact of heavy ion irradiation on the induction of autophagy in irradiated C2C12 mouse myoblasts and their non-targeted bystander cells. In irradiated cells, ultrastructural analysis revealed the accumulation of autophagic structures at various stages of autophagy (id est (i.e.) phagophores, autophagosomes and autolysosomes) within 20 min after irradiation. Multivesicular bodies (MVBs) and autolysosomes containing MVBs (amphisomes) were also observed. Heavy ion irradiation increased the staining of microtubule-associated protein 1 light chain 3 and LysoTracker Red (LTR). Such enhanced staining was suppressed by an autophagy inhibitor 3-methyladenine. In addition to irradiated cells, bystander cells were also positive with LTR staining. Altogether, these results suggest that heavy ion irradiation induces autophagy not only in irradiated myoblasts but also in their bystander cells. (author)

  7. Phytosanitary irradiation - Development and application

    Science.gov (United States)

    Hallman, Guy J.; Loaharanu, Paisan

    2016-12-01

    Phytosanitary irradiation, the use of ionizing radiation to disinfest traded agricultural commodities of regulated pests, is a growing use of food irradiation that has great continued potential for increase in commercial application. In 2015 approximately 25,000 t of fresh fruits and vegetables were irradiated globally for phytosanitary purposes. Phytosanitary irradiation has resulted in a paradigm shift in phytosanitation in that the final burden of proof of efficacy of the treatment has shifted from no live pests upon inspection at a port of entry (as for all previous phytosanitary treatments) to total dependence on certification that the treatment for target pests is based on adequate science and is commercially conducted and protected from post-treatment infestation. In this regard phytosanitary irradiation is managed more like a hazard analysis and critical control point (HACCP) approach more consistent with food safety than phytosanitation. Thus, phytosanitary irradiation offers a more complete and rigorous methodology for safeguarding than other phytosanitary measures. The role of different organizations in achieving commercial application of phytosanitary irradiation is discussed as well as future issues and applications, including new generic doses.

  8. Food irradiation technology

    International Nuclear Information System (INIS)

    Cetinkaya, N.

    1999-01-01

    Trade in food and agricultural products is important to all countries, the economies of many developing countries would be significantly improved if they were able to export more food and agricultural products. Unfortunately, many products can not be traded because they are infested with, or hosts to, harmful pests, contaminated with microorganisms, or spoil quickly. Foods contaminated with microorganisms cause economic losses, widespread illness and death. Several technologies and products have been developed to resolve problems in trading food and to improve food safety, but none can provide all the solutions. Irradiation is an effective technology to resolve technical problems in trade of many food and agricultural products, either as a stand- alone technology or in combination with others. As a disinfestation treatment it allows different levels of quarantine security to be targeted and it is one of few methods to control internal pests. The ability of irradiation virtually to eliminate key pathogenic organisms from meat, poultry, and spices is an important public health advantage. In addition to controlling pests and eliminating harmful bacteria, irradiation also extends the storage life of many foods. In the laboratories of Turkish Atomic Energy Authority, many research projects were completed on the effects of gamma irradiation to the storage life of chicken meat, anchovy, Turkish fermented sausage, dried and fresh fruits and vegetables and also research projects were conducted on the effects of gamma irradiation on microorganisms (Salmonella, Campylo-bacteria, E.coli and S.aureus in white and red meat) and parasites (food-borne, trichostrongylus spp. and Nematodes spp.)

  9. Food irradiation: An update

    International Nuclear Information System (INIS)

    Morrison, Rosanna M.

    1984-01-01

    Recent regulatory and commercial activity regarding food irradiation is highlighted. The effects of irradiation, used to kill insects and microorganisms which cause food spoilage, are discussed. Special attention is given to the current regulatory status of food irradiation in the USA; proposed FDA regulation regarding the use of irradiation; pending irradiation legislation in the US Congress; and industrial applications of irradiation

  10. Industrial irradiation

    International Nuclear Information System (INIS)

    Stirling, Andrew

    1995-01-01

    Production lines for rubber gloves would not appear to have much in common with particle physics laboratories, but they both use accelerators. Electron beam irradiation is often used in industry to improve the quality of manufactured goods or to reduce production cost. Products range from computer disks, shrink packaging, tyres, cables, and plastics to hot water pipes. Some products, such as medical goods, cosmetics and certain foodstuffs, are sterilized in this way. In electron beam irradiation, electrons penetrate materials creating showers of low energy electrons. After many collisions these electrons have the correct energy to create chemically active sites. They may either break molecular bonds or activate a site which promotes a new chemical linkage. This industrial irradiation can be exploited in three ways: breaking down a biological molecule usually renders it useless and kills the organism; breaking an organic molecule can change its toxicity or function; and crosslinking a polymer can strengthen it. In addition to traditional gamma irradiation using isotopes, industrial irradiation uses three accelerator configurations, each type defining an energy range, and consequently the electron penetration depth. For energies up to 750 kV, the accelerator consists of a DC potential applied to a simple wire anode and the electrons extracted through a slot in a coaxially mounted cylindrical cathode. In the 1-5 MeV range, the Cockcroft-Walton or Dynamitron( R ) accelerators are normally used. To achieve the high potentials in these DC accelerators, insulating SF6 gas and large dimension vessels separate the anode and cathode; proprietary techniques distinguish the various commercial models available. Above 5 MeV, the size of DC accelerators render them impractical, and more compact radiofrequency-driven linear accelerators are used. Irradiation electron beams are actually 'sprayed' over the product using a magnetic deflection system. Lower energy beams of

  11. Solid Polarized Targets and Applications

    International Nuclear Information System (INIS)

    Crabb, D. G.

    2008-01-01

    Examples are given of dynamically polarized targets in use today and how the subsystems have changed to meet the needs of todays experiments. Particular emphasis is placed on target materials such as ammonia and lithium deuteride. Recent polarization studies of irradiated materials such as butanol, deuterated butanol, polyethylene, and deuterated polyethylene are presented. The operation of two non-DNP target systems as well as applications of traditional DNP targets are briefly discussed

  12. Nonimaging solar concentrator with uniform irradiance

    Science.gov (United States)

    Winston, Roland; O'Gallagher, Joseph J.; Gee, Randy C.

    2004-09-01

    We report results of a study our group has undertaken under NREL/DOE auspices to design a solar concentrator with uniform irradiance on a planar target. This attribute is especially important for photovoltaic concentrators.

  13. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Beerens, H [Lille-1 Univ., 59 - Villeneuve-d' Ascq (France); Saint-Lebe, L

    1979-01-01

    Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment.

  14. Irradiation device

    International Nuclear Information System (INIS)

    Ransohoff, J.A.

    1984-01-01

    Carriers, after being loaded with product to be irradiated, are transported by an input-output conveyor system into an irradiation chamber where they are received in a horizontal arrangement on racks which may support different sizes and numbers of carriers. The racks are moved by a chamber conveyor system in an endless rectangular path about a radiation source. Packers shift the carriers on the racks to maintain nearest proximity to the radiation source. The carriers are shifted in position on each rack during successive rack cycles to produce even radiation exposure. The carriers may be loaded singly onto successive racks during a first cycle of movement thereof about the source, with loading of additional carriers, and/or unloading of carriers, onto each rack occurring on subsequent rack cycles of movement

  15. Food irradiation

    International Nuclear Information System (INIS)

    Roberts, P.B.

    1997-01-01

    Food can be provided with extra beneficial properties by physical processing. These benefits include a reduced possibility of food poisoning, or an increased life of the food. We are familiar with pasteurisation of milk, drying of vegetables, and canning of fruit. These physical processes work because the food absorbs energy during treatment which brings about the changes needed. The energy absorbed in these examples is heat energy. Food irradiation is a less familiar process. It produces similar benefits to other processes and it can sometimes be applied with additional advantages over conventional processing. For example, because irradiation causes little heating, foods may look and taste more natural. Also, treatment can take place with the food in its final plastic wrappers, reducing the risk of re-contamination. (author). 1 ref., 4 figs., 1 tab

  16. Food irradiation

    International Nuclear Information System (INIS)

    Beerens, H.; Saint-Lebe, L.

    1979-01-01

    Various aspects of food treatment by cobalt 60 or caesium 137 gamma radiation are reviewed. One of the main applications of irradiation on foodstuffs lies in its ability to kill micro-organisms, lethal doses being all the lower as the organism concerned is more complex. The effect on parasites is also spectacular. Doses of 200 to 300 krad are recommended to destroy all parasites with no survival period and no resistance phenomenon has ever been observed. The action of gamma radiation on macromolecules was also investigated, the bactericide treatment giving rise to side effects by transformation of food components. Three examples were studied: starch, nucleic acids and a whole food, the egg. The organoleptic aspect of irradiation was examined for different treated foods, then the physical transformations of unpasteurized, heat-pasteurized and radio-pasteurized eggs were compared. The report ends with a brief analysis of the toxicity and conditions of application of the treatment [fr

  17. Endolymphatic irradiation

    International Nuclear Information System (INIS)

    Galvao, M.M.; Ianhez, L.E.; Sabbaga, E.

    1982-01-01

    The authors analysed the clinical evolution and the result of renal transplantation some years after irradiation in 24 patients (group I) who received endolymphatic 131 I as a pre-transplantation immunesuppresive measure. The control group (group II) consisted of 24 non-irradiated patients comparable to group I in age, sex, primary disease, type of donor and immunesuppressive therapy. Significant differences were observed between the two groups regarding such factors a incidence and reversibility of rejection crises in the first 60 post-transplantation days, loss of kidney due to rejection, and dosage of azathioprine. The authors conclude that this method, besides being harmless, has prolonged immunesuppressive action, its administration being advised for receptores of cadaver kidneys, mainly those who show positive cross-match against HLA antigens for painel. (Author) [pt

  18. Neutron irradiation therapy machine

    International Nuclear Information System (INIS)

    1980-01-01

    Conventional neutron irradiation therapy machines, based on the use of cyclotrons for producing neutron beams, use a superconducting magnet for the cyclotron's magnetic field. This necessitates complex liquid He equipment and presents problems in general hospital use. If conventional magnets are used, the weight of the magnet poles considerably complicates the design of the rotating gantry. Such a therapy machine, gantry and target facilities are described in detail. The use of protons and deuterons to produce the neutron beams is compared and contrasted. (U.K.)

  19. Evaluation of hardening by ion irradiation in molybdenum using nanoindentation techniques

    International Nuclear Information System (INIS)

    Iwakiri, Hirotomi; Watanabe, Hideo; Yoshida, Naoaki

    1997-01-01

    As a part of fundamental research on interaction of plasma and wall, some model experiments on loading of particles such as He, H and so forth suffered by plasma facing material were conducted for Mo in high Z material. As an evaluation method for it, nanoindentation technique was proposed. By this method, the hardness evaluation in surface neighboring damage range was conducted. As a result, in the helium irradiated materials, sufficient hardening was observed even at low dpa range impossible to recognize hardening on heavy ion and deuterium irradiated materials, and extreme hardening was established by formation of helium bubble at high dpa region. Furthermore, in the helium irradiated materials, recovery of hardening could not be observed even for annealed materials at 1173 K for 1 hr after irradiation. From such results, hardening promotion work due to helium and extreme thermal stability of the formed defects were elucidated. (B.K.)

  20. A measuring method of photo-electric cross section. Application to high-Z elements between 40 keV and 220 keV. Measurement of K absorption edge energy of Au, Th, U, Pu

    International Nuclear Information System (INIS)

    Chartier, J.-L.

    1977-09-01

    This study first describes a bent crystal monochromator developed for the production of monochromatic beams in a continuous energy range from 30 to 250 keV; it is completed by a metrological application of the device (determination of K absorption edge energy of Au, Th, U, Pu). A method and the associated experimental procedure were developed to measure the photo-electric cross section for high-Z elements; the results are presented with a relative uncertainty ranging between 3 and 6%. Finally, the experimental values are compared with values calculated from theories using self-consistent potential models [fr

  1. Glycoalkaloids and phenolic compounds in gamma irradiated potatoes

    International Nuclear Information System (INIS)

    Bergers, W.W.A.

    1980-01-01

    Potatoes were used to study the metabolic stress effects in irradiated vegetable products. The changes of the contents of specific target compounds (glycoalkaloids, phenolic acids and coumarins) in alcoholic extracts of gamma irradiated potatoes were studied for metabolic irradiation stress. Doses of up to 3 kGy were applied to potatoes of several varieties. (Auth.)

  2. Converter target chemistry - A new challenge to radioanalytical chemistry.

    Science.gov (United States)

    Choudhury, Dibyasree; Lahiri, Susanta

    2018-07-01

    The 1-2 GeV proton induced spallation reaction on the high Z materials like Hg, or lead bismuth eutectic (LBE), popularly known as converter targets, will produce strong flux of fast neutrons which would further react with fissile materials to produce intense radioactive ion beam (RIB). LBE offers suitability for use as converters over Hg but it suffers from the demerit of radiotoxic polonium production. These targets may be viewed as a store house of clinically important and other exotic radionuclides. For application of those radionuclides, radiochemical separation from bulk target material is of utmost importance. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. The effects of microstructure on propagation of laser-driven radiative heat waves in under-dense high-Z plasma

    Science.gov (United States)

    Colvin, J. D.; Matsukuma, H.; Brown, K. C.; Davis, J. F.; Kemp, G. E.; Koga, K.; Tanaka, N.; Yogo, A.; Zhang, Z.; Nishimura, H.; Fournier, K. B.

    2018-03-01

    This work was motivated by previous findings that the measured laser-driven heat front propagation velocity in under-dense TiO2/SiO2 foams is slower than the simulated one [Pérez et al., Phys. Plasmas 21, 023102 (2014)]. In attempting to test the hypothesis that these differences result from effects of the foam microstructure, we designed and conducted an experiment on the GEKKO laser using an x-ray streak camera to compare the heat front propagation velocity in "equivalent" gas and foam targets, that is, targets that have the same initial density, atomic weight, and average ionization state. We first discuss the design and the results of this comparison experiment. To supplement the x-ray streak camera data, we designed and conducted an experiment on the Trident laser using a new high-resolution, time-integrated, spatially resolved crystal spectrometer to image the Ti K-shell spectrum along the laser-propagation axis in an under-dense TiO2/SiO2 foam cylinder. We discuss the details of the design of this experiment, and present the measured Ti K-shell spectra compared to the spectra simulated with a detailed superconfiguration non-LTE atomic model for Ti incorporated into a 2D radiation hydrodynamic code. We show that there is indeed a microstructure effect on heat front propagation in under-dense foams, and that the measured heat front velocities in the TiO2/SiO2 foams are consistent with the analytical model of Gus'kov et al. [Phys. Plasmas 18, 103114 (2011)].

  4. Electron beam fusion targets

    International Nuclear Information System (INIS)

    Clauser, M.J.; Sweeney, M.A.

    1975-01-01

    R The behavior of the DT filled gold shells when irradiated by a variety of pulse shapes was studied. In these pulses the power (and beam current) was varied, but the voltage was kept constant at 1 MeV. In general the performance of the target, for a given peak power, was not significantly affected by the pulse shape. Pulses with rise times of up to half the implosion time do not significantly degrade the target performance. The use of the ''optimal pulse'' of laser fusion with a fixed peak power does not appear to improve the performance of these targets. The main function of the ''optimal pulse'' is to produce a large rho r of the target during the thermonuclear burn. In e-beam targets a total rho r of 5--10 g/cm 2 can be obtained without pulse shaping; the problem here is one of achieving high enough temperatures to ignite the DT. (U.S.)

  5. Argus target chamber

    International Nuclear Information System (INIS)

    Rienecker, F. Jr.; Glaros, S.S.; Kobierecki, M.

    1975-01-01

    A target chamber for application in the laser fusion program must satisfy some very basic requirements. (1) Provide a vacuum on the order of 10 -6 torr. (2) Support a microscopically small target in a fixed point in space and verify its location within 5 micrometers. (3) Contain an adjustable beam focusing system capable of delivering a number of laser beams onto the target simultaneously, both in time and space. (4) Provide access for diagnostics to evaluate the results of target irradiation. (5) Have flexibility to allow changes in targets, focusing optics and number of beams. The ARGUS laser which is now under construction at LLL will have a target chamber which meets these requirements in a simple economic manner. The chamber and auxiliary equipment are described, with reference to two double beam focusing systems; namely, lenses and ellipsoidal mirrors. Provision is made for future operation with four beams, using ellipsoidal mirrors for two-sided illumination and lens systems for tetragonal and tetrahedral irradiation

  6. Subaru High-z Exploration of Low-Luminosity Quasars (SHELLQs). III. Star formation properties of the host galaxies at z ≳ 6 studied with ALMA

    Science.gov (United States)

    Izumi, Takuma; Onoue, Masafusa; Shirakata, Hikari; Nagao, Tohru; Kohno, Kotaro; Matsuoka, Yoshiki; Imanishi, Masatoshi; Strauss, Michael A.; Kashikawa, Nobunari; Schulze, Andreas; Silverman, John D.; Fujimoto, Seiji; Harikane, Yuichi; Toba, Yoshiki; Umehata, Hideki; Nakanishi, Kouichiro; Greene, Jenny E.; Tamura, Yoichi; Taniguchi, Akio; Yamaguchi, Yuki; Goto, Tomotsugu; Hashimoto, Yasuhiro; Ikarashi, Soh; Iono, Daisuke; Iwasawa, Kazushi; Lee, Chien-Hsiu; Makiya, Ryu; Minezaki, Takeo; Tang, Ji-Jia

    2018-04-01

    We present our ALMA Cycle 4 measurements of the [C II] emission line and the underlying far-infrared (FIR) continuum emission from four optically low-luminosity (M1450 > -25) quasars at z ≳ 6 discovered by the Subaru Hyper Suprime Cam (HSC) survey. The [C II] line and FIR continuum luminosities lie in the ranges L_[C II] = (3.8-10.2)× 108 L_{⊙} and LFIR = (1.2-2.0) × 1011 L_{⊙}, which are at least one order of magnitude smaller than those of optically-luminous quasars at z ≳ 6. We estimate the star formation rates (SFRs) of our targets as ≃ 23-40 M_{⊙} yr-1. Their line and continuum-emitting regions are marginally resolved, and found to be comparable in size to those of optically-luminous quasars, indicating that their SFR or likely gas mass surface densities (key controlling parameter of mass accretion) are accordingly different. The L_[C II]/L_FIR ratios of the hosts, ≃ (2.2-8.7) × 10-3, are fully consistent with local star-forming galaxies. Using the [C II] dynamics, we derived their dynamical masses within a radius of 1.5-2.5 kpc as ≃ (1.4-8.2) × 1010 M_{⊙}. By interpreting these masses as stellar ones, we suggest that these faint quasar hosts are on or even below the star-forming main sequence at z ˜ 6, i.e., they appear to be transforming into quiescent galaxies. This is in contrast to the optically-luminous quasars at those redshifts, which show starburst-like properties. Finally, we find that the ratios of black hole mass to host galaxy dynamical mass of most of the low-luminosity quasars, including the HSC ones, are consistent with the local value. The mass ratios of the HSC quasars can be reproduced by a semi-analytical model that assumes merger-induced black hole host galaxy evolution.

  7. WE-F-16A-04: Micro-Irradiator Treatment Verification with High-Resolution 3D-Printed Rodent-Morphic Dosimeters

    International Nuclear Information System (INIS)

    Bache, S; Belley, M; Benning, R; Adamovics, J; Stanton, I; Therien, M; Yoshizumi, T; Oldham, M

    2014-01-01

    Purpose: Pre-clinical micro-radiation therapy studies often utilize very small beams (∼0.5-5mm), and require accurate dose delivery in order to effectively investigate treatment efficacy. Here we present a novel high-resolution absolute 3D dosimetry procedure, capable of ∼100-micron isotopic dosimetry in anatomically accurate rodent-morphic phantoms Methods: Anatomically accurate rat-shaped 3D dosimeters were made using 3D printing techniques from outer body contours and spinal contours outlined on CT. The dosimeters were made from a radiochromic plastic material PRESAGE, and incorporated high-Z PRESASGE inserts mimicking the spine. A simulated 180-degree spinal arc treatment was delivered through a 2 step process: (i) cone-beam-CT image-guided positioning was performed to precisely position the rat-dosimeter for treatment on the XRad225 small animal irradiator, then (ii) treatment was delivered with a simulated spine-treatment with a 180-degree arc with 20mm x 10mm cone at 225 kVp. Dose distribution was determined from the optical density change using a high-resolution in-house optical-CT system. Absolute dosimetry was enabled through calibration against a novel nano-particle scintillation detector positioned in a channel in the center of the distribution. Results: Sufficient contrast between regular PRESAGE (tissue equivalent) and high-Z PRESAGE (spinal insert) was observed to enable highly accurate image-guided alignment and targeting. The PRESAGE was found to have linear optical density (OD) change sensitivity with respect to dose (R 2 = 0.9993). Absolute dose for 360-second irradiation at isocenter was found to be 9.21Gy when measured with OD change, and 9.4Gy with nano-particle detector- an agreement within 2%. The 3D dose distribution was measured at 500-micron resolution Conclusion: This work demonstrates for the first time, the feasibility of accurate absolute 3D dose measurement in anatomically accurate rat phantoms containing variable density PRESAGE

  8. Biology of food irradiation

    International Nuclear Information System (INIS)

    Murray, D.R.

    1990-01-01

    The author presents his arguments for food scientists and biologists that the hazards of food irradiation outweigh the benefits. The subject is discussed in the following sections: introduction (units, mutagenesis, seed viability), history of food irradiation, effects of irradiation on organoleptic qualities of staple foods, radiolytic products and selective destruction of nutrients, production of microbial toxins in stored irradiated foods and loss of quality in wheat, deleterious consequences of eating irradiated foods, misrepresentation of the facts about food irradiation. (author)

  9. Fabrication of inert matrices for heterogeneous transmutation. EFTTRA-T2 (RAS 2) irradiation programme

    International Nuclear Information System (INIS)

    Boshoven, J.G.; Hein, H.; Konings, R.J.M.

    1996-07-01

    This report describes the fabrication of targets containing inert matrices for the heterogeneous transmutation of plutonium and minor actinides. These targets will be irradiated in the EFTTRA-T2 (RAS-2) irradiation programme. The selection, preparation and characterization of the inert matrices and fabrication and loading of the irradiation capsules are discussed. (orig.)

  10. Graphite target for the spiral project

    International Nuclear Information System (INIS)

    Putaux, J.C.; Ducourtieux, M.; Ferro, A.; Foury, P.; Kotfila, L.; Mueller, A.C.; Obert, J.; Pauwels, N.; Potier, J.C.; Proust, J.; Loiselet, M.

    1996-01-01

    A study of the thermal and physical properties of graphite targets for the SPIRAL project is presented. The main objective is to develop an optimized set-up both mechanically and thermally resistant, presenting good release properties (hot targets with thin slices). The results of irradiation tests concerning the mechanical and thermal resistance of the first prototype of SPIRAL target with conical geometry are presented. The micro-structural properties of the graphite target is also studied, in order to check that the release properties are not deteriorated by the irradiation. Finally, the results concerning the latest pilot target internally heated by an electrical current are shown. (author)

  11. Irradiation Facilities at CERN

    CERN Document Server

    Gkotse, Blerina; Carbonez, Pierre; Danzeca, Salvatore; Fabich, Adrian; Garcia, Alia, Ruben; Glaser, Maurice; Gorine, Georgi; Jaekel, Martin, Richard; Mateu,Suau, Isidre; Pezzullo, Giuseppe; Pozzi, Fabio; Ravotti, Federico; Silari, Marco; Tali, Maris

    2017-01-01

    CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

  12. Perspective on food irradiation

    International Nuclear Information System (INIS)

    Newsome, R.L.

    1987-01-01

    A brief review summarizes current scientific information on the safety and efficacy of irradiation processing of foods. Attention is focused on: specifics of the irradiation process and its effectiveness in food preservation; the historical development of food irradiation technology in the US; the response of the Institute of Food Technologists to proposed FDA guidelines for food irradiation; the potential uses of irradiation in the US food industry; and the findings of the absence of toxins and of unaltered nutrient density (except possibly for fats) in irradiated foods. The misconceptions of consumers concerning perceived hazards associated with food irradiation, as related to consumer acceptance, also are addressed

  13. Tailoring molybdenum nanostructure evolution by low-energy He{sup +} ion irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Tripathi, J.K., E-mail: jtripat@purdue.edu; Novakowski, T.J.; Hassanein, A.

    2015-10-30

    flux of 1.2 × 10{sup 21} ions m{sup −2} s{sup −1}) is quite similar to those for 2.6 × 10{sup 24} ions m{sup −2} fluence, the nanostructure wall width extends up to ∼45 nm more and has a quite different nanostructured surface. Ex-situ X-ray photoelectron spectroscopy studies show a sequential reduction in at.% of Mo 3d doublets with fluence, leading to the complete depletion of 2.6 × 10{sup 24} ions m{sup −2} at 973 K. For 2.6 × 10{sup 24} ions m{sup −2} fluence irradiation at 973 K, only MoO{sub 3} 3d doublets were observed. However, the Mo 3d doublets reappear at 1273 K irradiation, where a variety of nanostructures were observed with relatively much lower density than that of Mo fuzz. As in the microscopy studies, the reflectivity measurements also show a sequential reduction with ion fluence, leading to almost zero reflectivity value for fully grown fuzzy structures. The study is significant in the understanding of fuzz formation on high-Z refractory metals for fusion applications; in addition, the observed MoO{sub 3} fuzz has potential application in solar power concentration technology and in water splitting for hydrogen production.

  14. Tailoring molybdenum nanostructure evolution by low-energy He+ ion irradiation

    International Nuclear Information System (INIS)

    Tripathi, J.K.; Novakowski, T.J.; Hassanein, A.

    2015-01-01

    fluence, the nanostructure wall width extends up to ∼45 nm more and has a quite different nanostructured surface. Ex-situ X-ray photoelectron spectroscopy studies show a sequential reduction in at.% of Mo 3d doublets with fluence, leading to the complete depletion of 2.6 × 10 24 ions m −2 at 973 K. For 2.6 × 10 24 ions m −2 fluence irradiation at 973 K, only MoO 3 3d doublets were observed. However, the Mo 3d doublets reappear at 1273 K irradiation, where a variety of nanostructures were observed with relatively much lower density than that of Mo fuzz. As in the microscopy studies, the reflectivity measurements also show a sequential reduction with ion fluence, leading to almost zero reflectivity value for fully grown fuzzy structures. The study is significant in the understanding of fuzz formation on high-Z refractory metals for fusion applications; in addition, the observed MoO 3 fuzz has potential application in solar power concentration technology and in water splitting for hydrogen production.

  15. Tailoring molybdenum nanostructure evolution by low-energy He+ ion irradiation

    Science.gov (United States)

    Tripathi, J. K.; Novakowski, T. J.; Hassanein, A.

    2015-10-01

    nm more and has a quite different nanostructured surface. Ex-situ X-ray photoelectron spectroscopy studies show a sequential reduction in at.% of Mo 3d doublets with fluence, leading to the complete depletion of 2.6 × 1024 ions m-2 at 973 K. For 2.6 × 1024 ions m-2 fluence irradiation at 973 K, only MoO3 3d doublets were observed. However, the Mo 3d doublets reappear at 1273 K irradiation, where a variety of nanostructures were observed with relatively much lower density than that of Mo fuzz. As in the microscopy studies, the reflectivity measurements also show a sequential reduction with ion fluence, leading to almost zero reflectivity value for fully grown fuzzy structures. The study is significant in the understanding of fuzz formation on high-Z refractory metals for fusion applications; in addition, the observed MoO3 fuzz has potential application in solar power concentration technology and in water splitting for hydrogen production.

  16. Neutronic and thermal-hydraulic analysis of a device for irradiation of LEU UAl{sub x}-Al targets for {sup 99}Mo production in the IEA-R1 reactor; Analises neutronica e termo-hidraulica de um dispositivo para irradiacao de alvos tipo LEU de UAl{sub x}-Al para producao de {sup 99}MO no reator IEA-R1

    Energy Technology Data Exchange (ETDEWEB)

    Nishiyama, Pedro Julio Batista de Oliveira

    2012-07-01

    Technetium-99m ({sup 99m}Tc), the product of radioactive decay of molybdenum-99 ( Mo), is one of the most widely used radioisotope in nuclear medicine, covering approximately 80% of all radiodiagnosis procedures in the world. Nowadays, Brazil requires an amount of about 450 Ci of {sup 99}Mo per week. Due to the crisis and the shortage of {sup 99}Mo supply chain that has been observed on the world since 2008, IPEN/CNEN-SP decided to develop a project to produce {sup 99}Mo through fission of uranium-235. The objective of this dissertation was the development of neutronic and thermal-hydraulic calculations to evaluate the operational safety of a device for {sup 99}Mo production to be irradiated in the IEA-Rl reactor core at 5 MW. In this device will be placed ten targets of UAl{sub x}-Al dispersion fuel with low enriched uranium (LEU) and density of 2.889 gU/cm{sup 3}. For the neutronic calculations were utilized the computer codes HAMMER-TECHNION and CITATION and the maximum temperatures reached in the targets were calculated with the code MTRCR-IEA-R1. The analysis demonstrated that the device irradiation will occur without adverse consequences to the operation of the reactor. The total amount of {sup 99}Mo was calculated with the program SCALE and considering that the time needed for the chemical processing and recovering of the {sup 99}Mo will be five days after the irradiation, we have that the {sup 99}Mo activity available for distribution will be 176 Ci for 3 days of irradiation, 236 Ci for 5 days of irradiation and 272 Ci for 7 days of targets irradiation. (author)'.

  17. Isotopic anomalies in high Z elements: Uranium?

    International Nuclear Information System (INIS)

    Jovanovic, S.; Reed, G.W. Jr.; Essling, A.M.; Rauh, E.G.; Graczyk, D.G.

    1989-03-01

    Uranium in terrestrial volcanic ejecta from mantle-related sources has been analyzed mass spectrometrically. The objective was to seek supporting evidence for or refutation isotopic variations reported by Fried et al. (1985) for some such samples. The possibility that terrestrial U is not of constant isotopic composition is extraordinary. If true, mechanisms for creating the variation must be sought and the lack of homogenization within the earth addressed. Samples of 100 grams or more were processed in order to minimize reagent and environmental (laboratory) blank interference and to permit isolation of large amounts (several to tens of μg) of U for the mass spectrometer (MS) measurements, which utilizes aliquots of /approximately/1 μg. Aliquants from four volcanic samples gave data which indicate enrichments of 235 U ranging from 0.2% to 5.9% in the 235/238 ratio relative normal uranium ratios. These relative enrichments are consistent with, and in some cases, higher than the 0.18% enrichment reported by Fried et al. (1985) for two volcanic lava samples. However, we were not able to reproduce their results on the Kilauea lava for which they report 0.18% 235 U enrichment. The relative error in our MS ratios is 0.05% -- 0.07%. 1 tab

  18. Electron beam irradiating device

    Energy Technology Data Exchange (ETDEWEB)

    Shinohara, K

    1969-12-20

    The efficiency of an electron beam irradiating device is heightened by improving the irradiation atmosphere and the method of cooling the irradiation window. An irradiation chamber one side of which incorporates the irradiation windows provided at the lower end of the scanner is surrounded by a suitable cooling system such as a coolant piping network so as to cool the interior of the chamber which is provided with circulating means at each corner to circulate and thus cool an inert gas charged therewithin. The inert gas, chosen from a group of such gases which will not deleteriously react with the irradiating equipment, forms a flowing stream across the irradiation window to effect its cooling and does not contaminate the vacuum exhaust system or oxidize the filament when penetrating the equipment through any holes which the foil at the irradiation window may incur during the irradiating procedure.

  19. Suppression of the Rayleigh-Taylor instability due to self-radiation in a multiablation target

    International Nuclear Information System (INIS)

    Fujioka, Shinsuke; Sunahara, Atsushi; Nishihara, Katsunobu; Johzaki, Tomoyuki; Shiraga, Hiroyuki; Shigemori, Keisuke; Nakai, Mitsuo; Ikegawa, Tadashi; Murakami, Masakatsu; Nagai, Keiji; Norimatsu, Takayoshi; Azechi, Hiroshi; Yamanaka, Tatsuhiko; Ohnishi, Naofumi

    2004-01-01

    A scheme to suppress the Rayleigh-Taylor instability has been investigated for a direct-drive inertial fusion target. In a high-Z doped-plastic target, two ablation surfaces are formed separately--one driven by thermal radiation and the other driven by electron conduction. The growth of the Rayleigh-Taylor instability is significantly suppressed on the radiation-driven ablation surface inside the target due to the large ablation velocity and long density scale length. A significant reduction of the growth rate was observed in simulations and experiments using a brominated plastic target. A new direct-drive pellet was designed using this scheme

  20. Irradiation of goods

    International Nuclear Information System (INIS)

    Huebner, G.

    1992-01-01

    The necessary dose and the dosage limits to be observed depend on the kind of product and the purpose of irradiation. Product density and density distribution, product dimensions, but also packaging, transport and storage conditions are specific parameters influencing the conditions of irradiation. The kind of irradiation plant - electron accelerator or gamma plant - , its capacity, transport system and geometric arrangement of the radiation field are factors influencing the irradiation conditions as well. This is exemplified by the irradiation of 3 different products, onions, deep-frozen chicken and high-protein feed. Feasibilities and limits of the irradiation technology are demonstrated. (orig.) [de