WorldWideScience

Sample records for incident beam conditions

  1. Simulation of effects of incident beam condition in p-p elastic scattering

    International Nuclear Information System (INIS)

    Yu Lei; Zhang Gaolong; Le Xiaoyun; Tanihata, I.

    2014-01-01

    The simulation is performed for the monitors of beam direction and beam position for p-p elastic scattering. We set several variables to simulate the monitors of incident beam condition changes: beam positions at the quadrupole magnet and target in beam line polarimeter (BLP2), distance between quadrupole magnet and target, size of plastic scintillators, distance between the target in BLP2 and the centers of plastic scintillators, and beam polarization. Through the rotation of the coordinate system, the distributions of scattered and recoiled protons in the laboratory system were obtained. By analyzing the count yields in plastic scintillators at different beam positions, we found that the beam incident angular change (0.35°) could be detected when the asymmetry of geometries of left and right scintillators in BLP2 was changed by 6%. Therefore, the scattering angle measured in the experiment can be tracked by these monitors. (authors)

  2. Orientation-dependent ion beam sputtering at normal incidence conditions in FeSiAl alloy

    International Nuclear Information System (INIS)

    Batic, Barbara Setina; Jenko, Monika

    2010-01-01

    The authors have performed Ar+ broad ion beam sputtering of a polycrystalline Fe-Si-Al alloy at normal incidence at energies varying from 6 to 10 keV. Sputtering results in the formation of etch pits, which can be classified in three shapes: triangular, rectangular, and square. As each grain of individual orientation exhibits a certain type of pattern, the etch pits were correlated with the crystal orientations by electron backscattered diffraction technique.

  3. Grazing incidence beam expander

    Energy Technology Data Exchange (ETDEWEB)

    Akkapeddi, P.R.; Glenn, P.; Fuschetto, A.; Appert, Q.; Viswanathan, V.K.

    1985-01-01

    A Grazing Incidence Beam Expander (GIBE) telescope is being designed and fabricated to be used as an equivalent end mirror in a long laser resonator cavity. The design requirements for this GIBE flow down from a generic Free Electron Laser (FEL) resonator. The nature of the FEL gain volume (a thin, pencil-like, on-axis region) dictates that the output beam be very small. Such a thin beam with the high power levels characteristic of FELs would have to travel perhaps hundreds of meters or more before expanding enough to allow reflection from cooled mirrors. A GIBE, on the other hand, would allow placing these optics closer to the gain region and thus reduces the cavity lengths substantially. Results are presented relating to optical and mechanical design, alignment sensitivity analysis, radius of curvature analysis, laser cavity stability analysis of a linear stable concentric laser cavity with a GIBE. Fabrication details of the GIBE are also given.

  4. The ATLAS Beam Conditions Monitor

    International Nuclear Information System (INIS)

    Cindro, V; Dolenc, I; Kramberger, G; Macek, B; Mandic, I; Mikuz', M; Zavrtanik, M; Dobos, D; Gorisek, A; Pernegger, H; Weilhammer, P; Frais-Koelbl, H; Griesmayer, E; Niegl, M; Kagan, H; Tardif, D; Trischuk, W

    2008-01-01

    Beam conditions and the potential detector damage resulting from their anomalies have pushed the LHC experiments to build their own beam monitoring devices. The ATLAS Beam Conditions Monitor (BCM) consists of two stations (forward and backward) of detectors each with four modules. The sensors are required to tolerate doses up to 500 kGy and in excess of 10 15 charged particles per cm 2 over the lifetime of the experiment. Each module includes two diamond sensors read out in parallel. The stations are located symmetrically around the interaction point, positioning the diamond sensors at z = ±184 cm and r = 55 mm (a pseudo- rapidity of about 4.2). Equipped with fast electronics (2 ns rise time) these stations measure time-of-flight and pulse height to distinguish events resulting from lost beam particles from those normally occurring in proton-proton interactions. The BCM also provides a measurement of bunch-by-bunch luminosities in ATLAS by counting in-time and out-of-time collisions. Eleven detector modules have been fully assembled and tested. Tests performed range from characterisation of diamond sensors to full module tests with electron sources and in proton testbeams. Testbeam results from the CERN SPS show a module median-signal to noise of 11:1 for minimum ionising particles incident at a 45-degree angle. The best eight modules were installed on the ATLAS pixel support frame that was inserted into ATLAS in the summer of 2007. This paper describes the full BCM detector system along with simulation studies being used to develop the logic in the back-end FPGA coincidence hardware

  5. The ATLAS Beam Conditions Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Cindro, V; Dolenc, I; Kramberger, G; Macek, B; Mandic, I; Mikuz' , M; Zavrtanik, M [Jozef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana (Slovenia); Dobos, D; Gorisek, A; Pernegger, H; Weilhammer, P [CERN, Geneva (Switzerland); Frais-Koelbl, H; Griesmayer, E; Niegl, M [University of Applied Sciences Wiener Neustadt and Fotec, Wiener Neustadt (Austria); Kagan, H [Ohio State University, Columbus (United States); Tardif, D; Trischuk, W [University of Toronto, Toronto (Canada)], E-mail: william@physics.utoronto.ca

    2008-02-15

    Beam conditions and the potential detector damage resulting from their anomalies have pushed the LHC experiments to build their own beam monitoring devices. The ATLAS Beam Conditions Monitor (BCM) consists of two stations (forward and backward) of detectors each with four modules. The sensors are required to tolerate doses up to 500 kGy and in excess of 10{sup 15} charged particles per cm{sup 2} over the lifetime of the experiment. Each module includes two diamond sensors read out in parallel. The stations are located symmetrically around the interaction point, positioning the diamond sensors at z = {+-}184 cm and r = 55 mm (a pseudo- rapidity of about 4.2). Equipped with fast electronics (2 ns rise time) these stations measure time-of-flight and pulse height to distinguish events resulting from lost beam particles from those normally occurring in proton-proton interactions. The BCM also provides a measurement of bunch-by-bunch luminosities in ATLAS by counting in-time and out-of-time collisions. Eleven detector modules have been fully assembled and tested. Tests performed range from characterisation of diamond sensors to full module tests with electron sources and in proton testbeams. Testbeam results from the CERN SPS show a module median-signal to noise of 11:1 for minimum ionising particles incident at a 45-degree angle. The best eight modules were installed on the ATLAS pixel support frame that was inserted into ATLAS in the summer of 2007. This paper describes the full BCM detector system along with simulation studies being used to develop the logic in the back-end FPGA coincidence hardware.

  6. Characteristics of off-waist incident anomalous vortex beams in highly nonlocal media

    Directory of Open Access Journals (Sweden)

    Zhen-Feng Yang

    Full Text Available In this paper, we focus on the effect of the off-waist incident condition on the propagation characteristics of anomalous vortex beams (AVBs in nonlocal media. An expression is derived mathematically in order to describe the propagation dynamics of AVBs in nonlocal media under the off-waist incident condition. Typical propagation characteristics induced by the off-waist incident condition are illustrated numerically. It is found that the propagation characteristics under the off-waist incident condition are much different from those under the on-waist incident condition. Keywords: Off-waist incidence, Anomalous vortex beam, Nonlocal media

  7. ATLAS diamond Beam Condition Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Gorisek, A. [CERN (Switzerland)]. E-mail: andrej.gorisek@cern.ch; Cindro, V. [J. Stefan Institute (Slovenia); Dolenc, I. [J. Stefan Institute (Slovenia); Frais-Koelbl, H. [Fotec (Austria); Griesmayer, E. [Fotec (Austria); Kagan, H. [Ohio State University, OH (United States); Korpar, S. [J. Stefan Institute (Slovenia); Kramberger, G. [J. Stefan Institute (Slovenia); Mandic, I. [J. Stefan Institute (Slovenia); Meyer, M. [CERN (Switzerland); Mikuz, M. [J. Stefan Institute (Slovenia); Pernegger, H. [CERN (Switzerland); Smith, S. [Ohio State University, OH (United States); Trischuk, W. [University of Toronto (Canada); Weilhammer, P. [CERN (Switzerland); Zavrtanik, M. [J. Stefan Institute (Slovenia)

    2007-03-01

    The ATLAS experiment has chosen to use diamond for its Beam Condition Monitor (BCM) given its radiation hardness, low capacitance and short charge collection time. In addition, due to low leakage current diamonds do not require cooling. The ATLAS Beam Condition Monitoring system is based on single beam bunch crossing measurements rather than integrating the accumulated particle flux. Its fast electronics will allow separation of LHC collisions from background events such as beam gas interactions or beam accidents. There will be two stations placed symmetrically about the interaction point along the beam axis at z=+/-183.8cm. Timing of signals from the two stations will provide almost ideal separation of beam-beam interactions and background events. The ATLAS BCM module consists of diamond pad detectors of 1cm{sup 2} area and 500{mu}m thickness coupled to a two-stage RF current amplifier. The production of the final detector modules is almost done. A S/N ratio of 10:1 has been achieved with minimum ionizing particles (MIPs) in the test beam setup at KEK. Results from the test beams and bench measurements are presented.

  8. ATLAS diamond Beam Condition Monitor

    International Nuclear Information System (INIS)

    Gorisek, A.; Cindro, V.; Dolenc, I.; Frais-Koelbl, H.; Griesmayer, E.; Kagan, H.; Korpar, S.; Kramberger, G.; Mandic, I.; Meyer, M.; Mikuz, M.; Pernegger, H.; Smith, S.; Trischuk, W.; Weilhammer, P.; Zavrtanik, M.

    2007-01-01

    The ATLAS experiment has chosen to use diamond for its Beam Condition Monitor (BCM) given its radiation hardness, low capacitance and short charge collection time. In addition, due to low leakage current diamonds do not require cooling. The ATLAS Beam Condition Monitoring system is based on single beam bunch crossing measurements rather than integrating the accumulated particle flux. Its fast electronics will allow separation of LHC collisions from background events such as beam gas interactions or beam accidents. There will be two stations placed symmetrically about the interaction point along the beam axis at z=+/-183.8cm. Timing of signals from the two stations will provide almost ideal separation of beam-beam interactions and background events. The ATLAS BCM module consists of diamond pad detectors of 1cm 2 area and 500μm thickness coupled to a two-stage RF current amplifier. The production of the final detector modules is almost done. A S/N ratio of 10:1 has been achieved with minimum ionizing particles (MIPs) in the test beam setup at KEK. Results from the test beams and bench measurements are presented

  9. Reconstruction of FXR Beam Conditions

    International Nuclear Information System (INIS)

    Nexen, W E; Scarpetti, R D; Zentler, J

    2001-01-01

    Beam-envelope radius, envelope angle, and beam emittance can be derived from measurements of beam radius for at least three different transport conditions. We have used this technique to reconstruct exit parameters from the FXR injector and accelerator. We use a diamagnetic loop (DML) to measure the magnetic moment of the high current beam. With no assumptions about radial profile, we can derive the beam mean squire radius from the moment under certain easily met conditions. Since it is this parameter which is required for the reconstruction, it is evident that the DML is the ideal diagnostic for this technique. The simplest application of this technique requires at least three shots for a reconstruction but in reality requires averaging over many more shots because of shot to shot variation. Since DML measurements do not interfere with the beam, single shot time resolved measurements of the beam parameters appear feasible if one uses an array of at least three DMLs separated by known transport conditions

  10. ATLAS diamond Beam Condition Monitor

    CERN Document Server

    Gorišek, A; Dolenc, I; Frais-Kölbl, H; Griesmayer, E; Kagan, H; Korpar, S; Kramberger, G; Mandic, I; Meyer, M; Mikuz, M; Pernegger, H; Smith, S; Trischuk, W; Weilhammer, P; Zavrtanik, M

    2007-01-01

    The ATLAS experiment has chosen to use diamond for its Beam Condition Monitor (BCM) given its radiation hardness, low capacitance and short charge collection time. In addition, due to low leakage current diamonds do not require cooling. The ATLAS Beam Condition Monitoring system is based on single beam bunch crossing measurements rather than integrating the accumulated particle flux. Its fast electronics will allow separation of LHC collisions from background events such as beam gas interactions or beam accidents. There will be two stations placed symmetrically about the interaction point along the beam axis at . Timing of signals from the two stations will provide almost ideal separation of beam–beam interactions and background events. The ATLAS BCM module consists of diamond pad detectors of area and thickness coupled to a two-stage RF current amplifier. The production of the final detector modules is almost done. A S/N ratio of 10:1 has been achieved with minimum ionizing particles (MIPs) in the test bea...

  11. The ATLAS beam conditions monitor

    CERN Document Server

    Mikuz, M; Dolenc, I; Kagan, H; Kramberger, G; Frais-Kölbl, H; Gorisek, A; Griesmayer, E; Mandic, I; Pernegger, H; Trischuk, W; Weilhammer, P; Zavrtanik, M

    2006-01-01

    The ATLAS beam conditions monitor is being developed as a stand-alone device allowing to separate LHC collisions from background events induced either on beam gas or by beam accidents, for example scraping at the collimators upstream the spectrometer. This separation can be achieved by timing coincidences between two stations placed symmetric around the interaction point. The 25 ns repetition of collisions poses very stringent requirements on the timing resolution. The optimum separation between collision and background events is just 12.5 ns implying a distance of 3.8 m between the two stations. 3 ns wide pulses are required with 1 ns rise time and baseline restoration in 10 ns. Combined with the radiation field of 10/sup 15/ cm/sup -2/ in 10 years of LHC operation only diamond detectors are considered suitable for this task. pCVD diamond pad detectors of 1 cm/sup 2/ and around 500 mum thickness were assembled with a two-stage RF current amplifier and tested in proton beam at MGH, Boston and SPS pion beam at...

  12. An isodose shift technique for obliquely incident electron beams

    International Nuclear Information System (INIS)

    Ulin, K.; Sternick, E.S.

    1989-01-01

    It is well known that when an electron beam is incident obliquely on the surface of a phantom, the depth dose curve measured normal to the surface is shifted toward the surface. Based on geometrical arguments alone, the depth of the nth isodose line for an electron beam incident at an angle θ should be equal to the product of cos θ and the depth of the nth isodose line at normal incidence. This method, however, ignores the effects of scatter and can lead to significant errors in isodose placement for beams at large angles of incidence. A semi-empirical functional relationship and a table of isodose shift factors have been developed with which one may easily calculate the depth of any isodose line for beams at incident angles of 0 degree to 60 degree. The isodose shift factors are tabulated in terms of beam energy (6--22 MeV) and isodose line (10%--90%) and are shown to be relatively independent of beam size and incident angle for angles <60 degree. Extensive measurements have been made on a Varian Clinac 2500 linear accelerator with a parallel-plate chamber and polystyrene phantom. The dependence of the chamber response on beam angulation has been checked, and the scaling factor of the polystyrene phantom has been determined to be equal to 1.00

  13. Asymmetric valley-resolved beam splitting and incident modes in slanted graphene junctions

    International Nuclear Information System (INIS)

    Hsieh, S. H.; Chu, C. S.

    2016-01-01

    Electron injection into a graphene sheet through a slanted armchair graphene nanoribbon (AGNR) is investigated. An incident mode, or subband, in the AGNR is valley-unpolarized. Our attention is on the valley-resolved nature of the injected electron beams and its connection to the incident mode. It is known for a normal injection that an incident mode will split symmetrically into two valley-resolved beams of equal intensity. We show, in contrast, that slanted injections result in asymmetric valley-resolved beam splitting. The most asymmetric beam splitting cases, when one of the valley-resolved beams has basically disappeared, are found and the condition derived. This is shown not due to trigonal warping because it holds even in the low incident energy regime, as long as collimation allows. These most asymmetric beam splitting cases occur at energies within an energy interval near and include the subband edge of an incident mode. The physical picture is best illustrated by a projection of the slanted AGNR subband states onto that of the 2D graphene sheet. It follows that the disappearing of a valley-resolved beam coincides with the situation that the group velocities of the projected states in the corresponding valley are in backward directions

  14. Behavior of obliquely incident vector Bessel beams at planar interfaces

    KAUST Repository

    Salem, Mohamed

    2013-01-01

    We investigate the behavior of full-vector electromagnetic Bessel beams obliquely incident at an interface between two electrically different media. We employ a Fourier transform domain representation of Bessel beams to determine their behavior upon reflection and transmission. This transform, which is geometric in nature, consists of elliptical support curves with complex weighting associated with them. The behavior of the scattered field at an interface is highly complex, owing to its full-vector nature; nevertheless, this behavior has a straightforward representation in the transform domain geometry. The analysis shows that the reflected field forms a different vector Bessel beam, but in general, the transmitted field cannot be represented as a Bessel beam. Nevertheless, using this approach, we demonstrate a method to propagate a Bessel beam in the refractive medium by launching a non- Bessel beam at the interface. Several interesting phenomena related to the behavior of Bessel beams are illustrated, such as polarized reflection at Brewster\\'s angle incidence, and the Goos-Hänchen and Imbert-Federov shifts in the case of total reflection. © 2013 Optical Society of America.

  15. Behavior of obliquely incident vector Bessel beams at planar interfaces

    KAUST Repository

    Salem, Mohamed; Bagci, Hakan

    2013-01-01

    We investigate the behavior of full-vector electromagnetic Bessel beams obliquely incident at an interface between two electrically different media. We employ a Fourier transform domain representation of Bessel beams to determine their behavior upon reflection and transmission. This transform, which is geometric in nature, consists of elliptical support curves with complex weighting associated with them. The behavior of the scattered field at an interface is highly complex, owing to its full-vector nature; nevertheless, this behavior has a straightforward representation in the transform domain geometry. The analysis shows that the reflected field forms a different vector Bessel beam, but in general, the transmitted field cannot be represented as a Bessel beam. Nevertheless, using this approach, we demonstrate a method to propagate a Bessel beam in the refractive medium by launching a non- Bessel beam at the interface. Several interesting phenomena related to the behavior of Bessel beams are illustrated, such as polarized reflection at Brewster's angle incidence, and the Goos-Hänchen and Imbert-Federov shifts in the case of total reflection. © 2013 Optical Society of America.

  16. Trapping mechanisms in scattering of beams at grazing incidence from crystals

    International Nuclear Information System (INIS)

    Smith, R.; O'Connor, D.J.; Felsobuki, E.I. von-Nagy

    1993-01-01

    The trajectories of grazing incidence, 1 keV beams of Si incident on Cu{111} are investigated by means of molecular dynamics (MD) simulations and the conditions under which atoms in the beam can be trapped in the surface binding potential are investigated. The binding potentials for the Cu-Si dimers are calculated using ab initio methods for the neutral, anion and cation. These calculations estimate the binding potential and equilibrium separation for the potential used for the MD calculations. It is found that at 4 o incidence to the Cu{111} face, no trapping occurs for a perfect crystal surface undergoing no thermal vibrations. Trapping can occur for the Si neutral if thermal vibrations are included in the model. Trapping is predicted to occur near steps on the Cu{111} face but these are fairly rare events for the Si - particles. (Author)

  17. Study on laser welding of austenitic stainless steel by varying incident angle of pulsed laser beam

    Science.gov (United States)

    Kumar, Nikhil; Mukherjee, Manidipto; Bandyopadhyay, Asish

    2017-09-01

    In the present work, AISI 304 stainless steel sheets are laser welded in butt joint configuration using a robotic control 600 W pulsed Nd:YAG laser system. The objective of the work is of twofold. Firstly, the study aims to find out the effect of incident angle on the weld pool geometry, microstructure and tensile property of the welded joints. Secondly, a set of experiments are conducted, according to response surface design, to investigate the effects of process parameters, namely, incident angle of laser beam, laser power and welding speed, on ultimate tensile strength by developing a second order polynomial equation. Study with three different incident angle of laser beam 89.7 deg, 85.5 deg and 83 deg has been presented in this work. It is observed that the weld pool geometry has been significantly altered with the deviation in incident angle. The weld pool shape at the top surface has been altered from semispherical or nearly spherical shape to tear drop shape with decrease in incident angle. Simultaneously, planer, fine columnar dendritic and coarse columnar dendritic structures have been observed at 89.7 deg, 85.5 deg and 83 deg incident angle respectively. Weld metals with 85.5 deg incident angle has higher fraction of carbide and δ-ferrite precipitation in the austenitic matrix compared to other weld conditions. Hence, weld metal of 85.5 deg incident angle achieved higher micro-hardness of ∼280 HV and tensile strength of 579.26 MPa followed by 89.7 deg and 83 deg incident angle welds. Furthermore, the predicted maximum value of ultimate tensile strength of 580.50 MPa has been achieved for 85.95 deg incident angle using the developed equation where other two optimum parameter settings have been obtained as laser power of 455.52 W and welding speed of 4.95 mm/s. This observation has been satisfactorily validated by three confirmatory tests.

  18. The Association Between Pitch Conditions and the Incidence of ...

    African Journals Online (AJOL)

    shown to influence incidence of rugby injuries. Harsh weather conditions and detrimental effect on poor Kenyan rugby pitches create a unique environment for injury exposure. We conducted a whole population prospective cohort study to determine the association of pitch conditions with injury incidence and severity.

  19. Effect of incident beam and diffuse radiation on par absorption, photosynthesis and transpiration of sitka spruce - a simulation study

    International Nuclear Information System (INIS)

    Wang, Y.P.; Jarvis, P.G.

    1990-01-01

    A simulation model, Maestro, is used to study the influence of beam fraction in the incident radiation and the radiance distribution of the sky diffuse radiation on PAR absorption, photosynthesis and transpiration of a Sitka spruce (Picea sitchensis (Bong.) Carr) tree crown. It is concluded that inaccurate separation of beam and diffuse radiation leads to significant errors in estimating the amounts of PAR absorbed, photosynthesis and transpiration by a tree in the stand. Much more attention should be paid to adequate descriptions of the radiance distribution of the sky diffuse radiation under different sky conditions. A useful approach is proposed for simulating the incident global radiaiton in a physiological, process-based model

  20. Photoinjector beam quality improvement by shaping the wavefront of a drive laser with oblique incidence

    International Nuclear Information System (INIS)

    He Zhigang; Wang Xiaohui; Jia Qika

    2012-01-01

    To increase the quantum efficiency (QE) of a copper photocathode and reduce the thermal emittance of an electron beam, a drive laser with oblique incidence was adopted in a BNL type photocathode rf gun. The disadvantageous effects on the beam quality caused by oblique incidence were analyzed qualitatively. A simple way to solve the problems through wavefront shaping was introduced and the beam quality was improved. (authors)

  1. Polarization dependence in ELNES: Influence of probe convergence, collector aperture and electron beam incidence angle

    International Nuclear Information System (INIS)

    Le Bosse, J.C.; Epicier, T.; Jouffrey, B.

    2006-01-01

    The differential scattering cross section in electron energy loss near edge spectroscopy (ELNES) generally depends on the orientation of the Q wave vector transferred from the incident electron to an atomic core electron. In the case where the excited atom belongs to a threefold, fourfold or sixfold main rotation axis, the dipole cross section depends on the angle of Q with respect to this axis. In this paper, we restrict to this situation called dichroism. Furthermore, if we take into account the relativistic effects due to the high incident electron velocity, this dipole cross section also depends on the angle of Q with respect to the electron beam axis. It is due to these dependences that the shape of measured electron energy loss spectra varies with the electron beam incidence, the collector aperture, the incident beam convergence and the incident electron energy. The existence of a particular beam incidence angle for which the scattering cross section becomes independent of collection and beam convergence semi-angles is clearly underscored. Conversely, it is shown that EELS spectra do not depend on the beam incidence angle for a set of particular values of collection and convergence semi-angles. Particularly, in the case of a parallel incident beam, there is a collection semi-angle (often called magic angle) for which the cross section becomes independent of the beam orientation. This magic angle depends on the incident beam kinetic energy. If the incident electron velocity V is small compared with the light velocity c, this magic angle is about 3.975θ E (θ E is the scattering angle). It decreases to 0 when V approaches c. These results are illustrated in the case of the K boron edge in the boron nitride

  2. Flow conditioning for improved optical propagation of beams through regions bounded by surfaces of high solidity

    International Nuclear Information System (INIS)

    Robey, H.F.; Albrecht, G.F.; Freitas, B.L.

    1991-01-01

    A flow conditioning system has been designed to maximize the thermal homogeneity in an enclosed region through which a laser beam must propagate. In the present application, such an enclosed region exists between the Nd:glass disks of a high average power solid-state laser amplifier. Experiments have been conducted on a test facility to quantify the magnitude of the beam losses due to thermal scattering. It is shown that the intensity of the incoherent light which is thermally scattered from this region can be reduced to less than 0.1% of the incident-beam intensity under apropriate flow and cooling conditions

  3. X-ray topography using the forward transmitted beam under multiple-beam diffraction conditions

    Energy Technology Data Exchange (ETDEWEB)

    Tsusaka, Y., E-mail: tsusaka@sci.u-hyogo.ac.jp; Takano, H. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Takeda, S. [SPring-8 Service Co., Ltd., 1-20-5, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Yokoyama, K.; Matsui, J. [Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan); Kagoshima, Y. [Graduate School of Material Science, University of Hyogo, 3-2-1, Kouto, Kamigori, Hyogo 678-1297 (Japan); Synchrotron Radiation Nanotechnology Center, University of Hyogo, 1-490-2, Kouto, Shingu, Tatsuno, Hyogo 679-5165 (Japan)

    2016-02-15

    X-ray topographs are taken for a sapphire wafer with the [0001] surface normal, as an example, by forward transmitted synchrotron x-ray beams combined with two-dimensional electronic arrays in the x-ray detector having a spatial resolution of 1 μm. They exhibit no shape deformation and no position shift of the dislocation lines on the topographs. Since the topography is performed under multiple-beam diffraction conditions, the topographic images of a single diffraction (two-wave approximation condition) or plural diffractions (six-wave approximation condition) can be recorded without large specimen position changes. As usual Lang topographs, it is possible to determine the Burgers vector of each dislocation line. Because of high parallelism of the incoming x-rays and linear sensitivity of the electronic arrays to the incident x-rays, the present technique can be used to visualize individual dislocations in single crystals of the dislocation density as high as 1 × 10{sup 5} cm{sup −2}.

  4. Human Q fever incidence is associated to spatiotemporal environmental conditions

    Directory of Open Access Journals (Sweden)

    J.P.G. Van Leuken

    2016-12-01

    We conclude that environmental conditions are correlated to human Q fever incidence rate. Similar research with data from other outbreaks would be needed to more firmly establish our findings. This could lead to better estimations of the public health risk of a C. burnetii outbreak, and to more detailed and accurate hazard maps that could be used for spatial planning of livestock operations.

  5. Beam conditions monitors at CMS and LHC using diamond sensors

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Maria; Lohmann, Wolfgang [Desy-Zeuthen, Platanenallee 6, 15738 Zeuthen (Germany); Brandenburgische Technische Universitaet Cottbus, Konrad-Wachsmann-Allee 1, 03046 Cottbus (Germany); Castro-Carballo, Maria-Elena; Lange, Wolfgang; Novgorodova, Olga [Desy-Zeuthen, Platanenallee 6, 15738 Zeuthen (Germany); Walsh, Roberval [Desy-Hamburg, Notkestrasse 85, 22607 Hamburg (Germany)

    2012-07-01

    The Fast Beam Conditions Monitor (BCM1F) is a particle detector based on diamonds. Eight modules comprising a single crystal diamond, front-end electronics and an optical link are installed on both sides of the interaction point inside the tracker of the CMS detector. The back-end uses ADCs, TDCs and scalers to measure the amplitudes, arrival time and rates of beam-halo particles and collision products. These data are used to protect the inner tracker from adverse beam conditions, perform a fast monitoring of the luminosity and e.g. beam-gas interactions. Recently two additional BCM1F modules have been installed at other positions of the LHC to supplement the beam-loss monitors by a flux measurement with nanosecond time resolution. In the talk essential parameters of the system are presented and examples of beam conditions monitoring are reported.

  6. Simulation calculation for the energy deposition profile and the transmission fraction of intense pulsed electron beam at various incident angles

    International Nuclear Information System (INIS)

    Yang Hailiang; Qiu Aici; Zhang Jiasheng; Huang Jianjun; Sun Jianfeng

    2002-01-01

    The incident angles have a heavy effect on the intense pulsed electron beam energy deposition profile, energy deposition fraction and beam current transmission fraction in material. The author presents electron beam energy deposition profile and energy deposition fraction versus electron energy (0.5-2.0 MeV), at various incident angles for three aluminum targets of various thickness via theoretical calculation. The intense pulsed electron beam current transmission fractions versus electron energy (0.4-1.4 MeV) at various incident angles for three thickness of carbon targets were also theoretically calculated. The calculation results indicate that the deposition energy in unit mass of material surface layer increase with the rise of electron beam incident angle, and electron beam with low incident angle (closer to normal incident angle) penetrates deeper into the target material. The electron beams deposit more energy in unit mass of material surface layer at 60 degree-70 degree incident angle

  7. Unified beam splitter of fused silica grating under the second Bragg incidence.

    Science.gov (United States)

    Sun, Zhumei; Zhou, Changhe; Cao, Hongchao; Wu, Jun

    2015-11-01

    A unified design for a 1×2 beam splitter of dielectric rectangular transmission gratings under the second Bragg incidence is theoretically investigated for TE- and TM-polarized light. The empirical equations of the relative grating parameters (ratio of the absolute one to incidence wavelength) for this design are also obtained with the simplified modal method (SMM). The influences of polarization of incident light and relative grating parameters on the performance of the beam splitter are thoroughly studied based on the SMM and rigorous coupled-wave analysis. Two specific gratings are demonstrated with an even split and high diffraction efficiency (>94% for TE polarization and >97% for the TM counterpart). The unified profiles of the 1×2 beam splitter are independent from the incidence wavelength since the refractive index of fused silica is roughly a constant over a wide range of wavelengths, which should be promising for future applications.

  8. Multiple scattering of a zero-order Bessel beam with arbitrary incidence by an aggregate of uniaxial anisotropic spheres

    International Nuclear Information System (INIS)

    Li, Z.J.; Wu, Z.S.; Qu, T.; Shang, Q.C.; Bai, L.

    2016-01-01

    Based on the generalized multiparticle Mie theory, multiple scattering of an aggregate of uniaxial anisotropic spheres illuminated by a zero-order Bessel beam (ZOBB) with arbitrary propagation direction is investigated. The particle size and configuration are arbitrary. The arbitrary incident Bessel beam is expanded in terms of spherical vector wave functions (SVWFs). Utilizing the vector addition theorem of SVWFs, interactive and total scattering coefficients are derived through the continuous boundary conditions on which the interaction of the particles is considered. The accuracy of the theory and codes are verified by comparing results with those obtained for arbitrary plane wave incidence by CST simulation, and for ZOBB incidence by a numerical method. The effects of angle of incidence, pseudo-polarization angle, half-conical angle, beam center position, and permittivity tensor elements on the radar cross sections (RCSs) of several types of collective uniaxial anisotropic spheres, such as a linear chain, a 4×4×4 cube-shaped array, and other periodical structures consisting of massive spheres, are numerically analyzed. Selected results on the properties of typical particles such as TiO 2 , SiO 2 , or other particle lattices are calculated. This investigation could provide an effective test for further research on the scattering characteristics of an aggregate of anisotropic spheres by a high-order Bessel vortex beam. The results have important application in optical tweezers and particle manipulation. - Highlights: • Scattering of Bessel beam by an aggregate of uniaxial anisotropic spheres is studied. • The zero-order Bessel beam propagates and polarizes along arbitrary direction. • The accuracy of expansion coefficients, the scattering theory and codes is verified. • Effects of various parameters on scattering properties are numerically discussed. • Scattering properties of several type of periodical array are numerically analyzed.

  9. Oblique incidence of electron beams - comparisons between calculated and measured dose distributions

    International Nuclear Information System (INIS)

    Karcher, J.; Paulsen, F.; Christ, G.

    2005-01-01

    Clinical applications of high-energy electron beams, for example for the irradiation of internal mammary lymph nodes, can lead to oblique incidence of the beams. It is well known that oblique incidence of electron beams can alter the depth dose distribution as well as the specific dose per monitor unit. The dose per monitor unit is the absorbed dose in a point of interest of a beam, which is reached with a specific dose monitor value (DIN 6814-8[5]). Dose distribution and dose per monitor unit at oblique incidence were measured with a small-volume thimble chamber in a water phantom, and compared to both normal incidence and calculations of the Helax TMS 6.1 treatment planning system. At 4 MeV and 60 degrees, the maximum measured dose per monitor unit at oblique incidence was decreased up to 11%, whereas at 18MeV and 60 degrees this was increased up to 15% compared to normal incidence. Comparisons of measured and calculated dose distributions showed that the predicted dose at shallow depths is usually higher than the measured one, whereas it is smaller at depths beyond the depth of maximum dose. On the basis of the results of these comparisons, normalization depths and correction factors for the dose monitor value were suggested to correct the calculations of the dose per monitor unit. (orig.)

  10. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.W.; Lager, D.L.

    1985-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  11. Automation of neutral beam source conditioning with artificial intelligence techniques

    International Nuclear Information System (INIS)

    Johnson, R.R.; Canales, T.; Lager, D.

    1986-01-01

    This paper describes a system that automates neutral beam source conditioning. The system achieves this with artificial intelligence techniques. The architecture of the system is presented followed by a description of its performance

  12. Luminosity measurement and beam condition monitoring at CMS

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Jessica Lynn [DESY, Zeuthen (Germany)

    2015-07-01

    The BRIL system of CMS consists of instrumentation to measure the luminosity online and offline, and to monitor the LHC beam conditions inside CMS. An accurate luminosity measurement is essential to the CMS physics program, and measurement of the beam background is necessary to ensure safe operation of CMS. In expectation of higher luminosity and denser proton bunch spacing during LHC Run II, many of the BRIL subsystems are being upgraded and others are being added to complement the existing measurements. The beam condition monitor (BCM) consists of several sets of diamond sensors used to measure online luminosity and beam background with a single-bunch-crossing resolution. The BCM also detects when beam conditions become unfavorable for CMS running and may trigger a beam abort to protect the detector. The beam halo monitor (BHM) uses quartz bars to measure the background of the incoming beams at larger radii. The pixel luminosity telescope (PLT) consists of telescopes of silicon sensors designed to provide a CMS online and offline luminosity measurement. In addition, the forward hadronic calorimeter (HF) will deliver an independent luminosity measurement, making the whole system robust and allowing for cross-checks of the systematics. Data from each of the subsystems will be collected and combined in the BRIL DAQ framework, which will publish it to CMS and LHC. The current status of installation and commissioning results for the BRIL subsystems are given.

  13. Calculated neutron spectrum from 800-MeV protons incident on a copper beam stop

    International Nuclear Information System (INIS)

    Perry, D.G.

    1975-10-01

    A Monte Carlo calculation was performed to obtain the neutron spectrum generated by 800-MeV protons incident on the LAMPF main copper beam stop. The total flux is calculated to be of the order of 10 13 n/cm 2 -sec-mA at full-beam intensity of 1 mA, with flux spectra calculated for angles of 20 0 , 30 0 , 60 0 , 90 0 , 120 0 , and 150 0 . (auth)

  14. Development of Beam Conditions Monitor for the ATLAS experiment

    CERN Document Server

    Dolenc Kittelmann, Irena; Mikuž, M

    2008-01-01

    If there is a failure in an element of the accelerator the resulting beam losses could cause damage to the inner tracking devices of the experiments. This thesis presents the work performed during the development phase of a protection system for the ATLAS experiment at the LHC. The Beam Conditions Monitor (BCM) system is a stand-alone system designed to detect early signs of beam instabilities and trigger a beam abort in case of beam failures. It consists of two detector stations positioned at z=±1.84m from the interaction point. Each station comprises four BCM detector modules installed symmetrically around the beam pipe with sensors located at r=55 mm. This structure will allow distinguishing between anomalous events (beam gas and beam halo interactions, beam instabilities) and normal events due to proton-proton interaction by measuring the time-of-flight as well as the signal pulse amplitude from detector modules on the timescale of nanoseconds. Additionally, the BCM system aims to provide a coarse instan...

  15. Calculation of multi-dimensional dose distribution in medium due to proton beam incidence

    International Nuclear Information System (INIS)

    Kawachi, Kiyomitsu; Inada, Tetsuo

    1978-01-01

    The method of analyzing the multi-dimensional dose distribution in a medium due to proton beam incidence is presented to obtain the reliable and simplified method from clinical viewpoint, especially for the medical treatment of cancer. The heavy ion beam being taken out of an accelerator has to be adjusted to fit cancer location and size, utilizing a modified range modulator, a ridge filter, a bolus and a special scanning apparatus. The precise calculation of multi-dimensional dose distribution of proton beam is needed to fit treatment to a limit part. The analytical formulas consist of those for the fluence distribution in a medium, the divergence of flying range, the energy distribution itself, the dose distribution in side direction and the two-dimensional dose distribution. The fluence distribution in polystyrene in case of the protons with incident energy of 40 and 60 MeV, the energy distribution of protons at the position of a Bragg peak for various values of incident energy, the depth dose distribution in polystyrene in case of the protons with incident energy of 40 and 60 MeV and average energy of 100 MeV, the proton fluence and dose distribution as functions of depth for the incident average energy of 250 MeV, the statistically estimated percentage errors in the proton fluence and dose distribution, the estimated minimum detectable tumor thickness as a function of the number of incident protons for the different incident spectra with average energy of 250 MeV, the isodose distribution in a plane containing the central axis in case of the incident proton beam of 3 mm diameter and 40 MeV and so on are presented as the analytical results, and they are evaluated. (Nakai, Y.)

  16. Commissioning and first operation of the pCVD diamond ATLAS Beam Conditions Monitor

    CERN Document Server

    Dobos, D

    2009-01-01

    The main aim of the ATLAS Beam Conditions Monitor is to protect the ATLAS Inner Detector silicon trackers from high radiation doses caused by LHC beam incidents, e.g. magnet failures. The BCM uses in total 16 1x1 cm2 500 μm thick polycrystalline chemical vapor deposition (pCVD) diamond sensors. They are arranged in 8 positions around the ATLAS LHC interaction point. Time difference measurements with sub nanosecond resolution are performed to distinguish between particles from a collision and spray particles from a beam incident. An abundance of the latter leads the BCM to provoke an abort of the LHC beam. A FPGA based readout system with a sampling rate of 2.56 GHz performs the online data analysis and interfaces the results to ATLAS and the beam abort system. The BCM diamond sensors, the detector modules and their readout system are described. Results of the operation with the first LHC beams are reported and results of commissioning and timing measurements (e.g. with cosmic muons) in preparation for first ...

  17. A Correction of Random Incidence Absorption Coefficients for the Angular Distribution of Acoustic Energy under Measurement Conditions

    DEFF Research Database (Denmark)

    Jeong, Cheol-Ho

    2009-01-01

    Most acoustic measurements are based on an assumption of ideal conditions. One such ideal condition is a diffuse and reverberant field. In practice, a perfectly diffuse sound field cannot be achieved in a reverberation chamber. Uneven incident energy density under measurement conditions can cause...... discrepancies between the measured value and the theoretical random incidence absorption coefficient. Therefore the angular distribution of the incident acoustic energy onto an absorber sample should be taken into account. The angular distribution of the incident energy density was simulated using the beam...... tracing method for various room shapes and source positions. The averaged angular distribution is found to be similar to a Gaussian distribution. As a result, an angle-weighted absorption coefficient was proposed by considering the angular energy distribution to improve the agreement between...

  18. Structured surface reflector design for oblique incidence beam splitter at 610 GHz.

    Science.gov (United States)

    Defrance, F; Casaletti, M; Sarrazin, J; Wiedner, M C; Gibson, H; Gay, G; Lefèvre, R; Delorme, Y

    2016-09-05

    An iterative alternate projection-based algorithm is developed to design structured surface reflectors to operate as beam splitters at GHz and THz frequencies. To validate the method, a surface profile is determined to achieve a reflector at 610 GHz that generates four equal-intensity beams towards desired directions of ±12.6° with respect to the specular reflection axis. A prototype is fabricated and the beam splitter behavior is experimentally demonstrated. Measurements confirm a good agreement (within 1%) with computer simulations using Feko, validating the method. The beam splitter at 610 GHz has a measured efficiency of 78% under oblique incidence illumination that ensures a similar intensity between the four reflected beams (variation of about 1%).

  19. Monte Carlo Investigation of Photon Beam Characteristics and its Variation with Incident Electron Beam Parameters for Indigenous Medical Linear Accelerator.

    Science.gov (United States)

    Mishra, Subhalaxmi; Dixit, P K; Selvam, T Palani; Yavalkar, Sanket S; Deshpande, D D

    2018-01-01

    A Monte Carlo model of a 6 MV medical linear accelerator (linac) unit built indigenously was developed using the BEAMnrc user code of the EGSnrc code system. The model was benchmarked against the measurements. Monte Carlo simulations were carried out for different incident electron beam parameters in the study. Simulation of indigenously developed linac unit has been carried out using the Monte Carlo based BEAMnrc user-code of the EGSnrc code system. Using the model, percentage depth dose (PDD), and lateral dose profiles were studied using the DOSXYZnrc user code. To identify appropriate electron parameters, three different distributions of electron beam intensity were investigated. For each case, the kinetic energy of the incident electron was varied from 6 to 6.5 MeV (0.1 MeV increment). The calculated dose data were compared against the measurements using the PTW, Germany make RFA dosimetric system (water tank MP3-M and 0.125 cm 3 ion chamber). The best fit of incident electron beam parameter was found for the combination of beam energy of 6.2 MeV and circular Gaussian distributed source in X and Y with FWHM of 1.0 mm. PDD and beam profiles (along both X and Y directions) were calculated for the field sizes from 5 cm × 5 cm to 25 cm × 25 cm. The dose difference between the calculated and measured PDD and profile values were under 1%, except for the penumbra region where the maximum deviation was found to be around 2%. A Monte Carlo model of indigenous linac (6 MV) has been developed and benchmarked against the measured data.

  20. The change in color matches with retinal angle of incidence of the colorimeter beams.

    Science.gov (United States)

    Alpern, M; Kitahara, H; Fielder, G H

    1987-01-01

    Differences between W.D.W. chromaticities of monochromatic lights obtained with all colorimeter beams incident on the retina "off-axis" and those found for lights striking the retina normally have been studied throughout the visible spectrum on 4 normal trichromats. The results are inconsistent with: (i) the assumption in Weale's theories of the Stiles-Crawford hue shift that the sets of absorption spectra of the visual pigments catching normally and obliquely incident photons are identical, and (ii) "self-screening" explanations for the change in color with angle of incidence on the retina. The color matching functions of a protanomalous trichromat are inconsistent with the hypothesis that the absorption spectra of the visual pigments catching normally incident photons in his retina are those catching obliquely incident photons in the normal retina.

  1. Conditional predictive inference for online surveillance of spatial disease incidence

    Science.gov (United States)

    Corberán-Vallet, Ana; Lawson, Andrew B.

    2012-01-01

    This paper deals with the development of statistical methodology for timely detection of incident disease clusters in space and time. The increasing availability of data on both the time and the location of events enables the construction of multivariate surveillance techniques, which may enhance the ability to detect localized clusters of disease relative to the surveillance of the overall count of disease cases across the entire study region. We introduce the surveillance conditional predictive ordinate as a general Bayesian model-based surveillance technique that allows us to detect small areas of increased disease incidence when spatial data are available. To address the problem of multiple comparisons, we incorporate a common probability that each small area signals an alarm when no change in the risk pattern of disease takes place into the analysis. We investigate the performance of the proposed surveillance technique within the framework of Bayesian hierarchical Poisson models using a simulation study. Finally, we present a case study of salmonellosis in South Carolina. PMID:21898522

  2. Ionization beam profile monitor for operation under hard environmental conditions

    International Nuclear Information System (INIS)

    Teterev, Yu.G.; Kaminski, G.; Phi Thanh Huong; Kaminski, G.; Kozik, E.

    2010-01-01

    The design and the performance of the Ionization Beam Profile Monitor (IBPM) operating on the residual gas ionization principle are described. The main advantage of the constructed device is the non-contact measuring method. Operating under hard environmental conditions it delivers the information about the primary beam position, profile and intensity in 'on-line' regime. It was found out that the device is capable to operate in vacuum in the range of 10 -6 /10 -3 mbar without the loss of the resolution power at the beam current as low as a few nA. The IBPM is prospective for beam profile monitoring due to long time. Emergency situations do not lead to decrease of its operability.

  3. Optimal condition for employing an axicon-generated Bessel beam to fabricate cylindrical microlens arrays

    Science.gov (United States)

    Luo, Zhi; Yin, Kai; Dong, Xinran; Duan, Ji’an

    2018-05-01

    A numerical algorithm, modelling the transformation from a Gaussian beam to a Bessel beam, is presented for the purpose to study the optimal condition for employing an axicon-generated Bessel beam to fabricate cylindrical microlens arrays (CMLAs). By applying the numerical algorithm to simulate the spatial intensity distribution behind the axicon under different defects of a rotund-apex and different diameter ratios of an incident beam to the axicon, we find that the diffraction effects formed by the axicon edge can be almost eliminated when the diameter ratio is less than 1:2, but the spatial intensity distribution is disturbed dramatically even a few tens of microns deviation of the apex, especially for the front part of the axicon-generated Bessel beam. Fortunately, the lateral intensity profile in the rear part still maintains a desirable Bessel curve. Therefore, the rear part of the Bessel area and the less than 1:2 diameter ratio are the optimal choice for employing an axicon-generated Bessel beam to implement surface microstructures fabrication. Furthermore, by applying the optimal conditions to direct writing microstructures on fused silica with a femtosecond (fs) laser, a large area close-packed CMLA is fabricated. The CMLA presents high quality and uniformity and its optical performance is also demonstrated.

  4. Continuum modeling of ion-beam eroded surfaces under normal incidence: Impact of stochastic fluctuations

    International Nuclear Information System (INIS)

    Dreimann, Karsten; Linz, Stefan J.

    2010-01-01

    Graphical abstract: Deterministic surface pattern (left) and its stochastic counterpart (right) arising in a stochastic damped Kuramoto-Sivashinsky equation that serves as a model equation for ion-beam eroded surfaces and is systematically investigated. - Abstract: Using a recently proposed field equation for the surface evolution of ion-beam eroded semiconductor target materials under normal incidence, we systematically explore the impact of additive stochastic fluctuations that are permanently present during the erosion process. Specifically, we investigate the dependence of the surface roughness, the underlying pattern forming properties and the bifurcation behavior on the strength of the fluctuations.

  5. 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.

  6. Ion beam irradiation of ceramics at fusion relevant conditions

    International Nuclear Information System (INIS)

    Zinkle, S.J.

    1991-01-01

    Ceramic materials are required at a variety of locations in proposed fusion reactors where significant ionizing and displacive fields may be present. Energetic ion beams are a useful tool for probing the effects of irradiation on the structure and electrical properties of ceramics over a wide range of experimental conditions. The advantages and disadvantages of using ion beams to provide information on anticipated ceramic radiation effects in a fusion reactor environment are discussed. In this paper particular emphasis is placed on microstructural changes and how the high helium generation rates associated with DT fusion neutrons affect cavity swelling

  7. Fast beam condition monitor for CMS. Performance and upgrade

    International Nuclear Information System (INIS)

    Leonard, Jessica L.; Bell, Alan; Burtowy, Piotr

    2014-05-01

    The CMS beam and radiation monitoring subsystem BCM1F (Fast Beam Condition Monitor) consists of 8 individual diamond sensors situated around the beam pipe within the pixel detector volume, for the purpose of fast bunch-by-bunch monitoring of beam background and collision products. In addition, effort is ongoing to use BCM1F as an online luminosity monitor. BCM1F will be running whenever there is beam in LHC, and its data acquisition is independent from the data acquisition of the CMS detector, hence it delivers luminosity even when CMS is not taking data. A report is given on the performance of BCM1F during LHC run I, including results of the van der Meer scan and on-line luminosity monitoring done in 2012. In order to match the requirements due to higher luminosity and 25 ns bunch spacing, several changes to the system must be implemented during the upcoming shutdown, including upgraded electronics and precise gain monitoring. First results from Run II preparation are shown.

  8. Fast Beam Condition Monitor for CMS: performance and upgrade

    CERN Document Server

    INSPIRE-00009152; Bell, Alan; Burtowy, Piotr; Dabrowski, Anne; Hempel, Maria; Henschel, Hans; Lange, Wolfgang; Lohmann, Wolfgang; Odell, Nathaniel; Penno, Marek; Pollack, Brian; Przyborowski, Dominik; Ryjov, Vladimir; Stickland, David; Walsh, Roberval; Warzycha, Weronika; Zagozdzinska, Agnieszka

    2014-11-21

    The CMS beam and radiation monitoring subsystem BCM1F (Fast Beam Condition Monitor) consists of 8 individual diamond sensors situated around the beam pipe within the pixel detector volume, for the purpose of fast bunch-by-bunch monitoring of beam background and collision products. In addition, effort is ongoing to use BCM1F as an online luminosity monitor. BCM1F will be running whenever there is beam in LHC, and its data acquisition is independent from the data acquisition of the CMS detector, hence it delivers luminosity even when CMS is not taking data. A report is given on the performance of BCM1F during LHC run I, including results of the van der Meer scan and on-line luminosity monitoring done in 2012. In order to match the requirements due to higher luminosity and 25 ns bunch spacing, several changes to the system must be implemented during the upcoming shutdown, including upgraded electronics and precise gain monitoring. First results from Run II preparation are shown.

  9. Effect of Brazil's conditional cash transfer programme on tuberculosis incidence.

    Science.gov (United States)

    Nery, J S; Rodrigues, L C; Rasella, D; Aquino, R; Barreira, D; Torrens, A W; Boccia, D; Penna, G O; Penna, M L F; Barreto, M L; Pereira, S M

    2017-07-01

    To evaluate the impact of the Brazilian cash transfer programme (Bolsa Família Programme, BFP) on tuberculosis (TB) incidence in Brazil from 2004 to 2012. We studied tuberculosis surveillance data using a combination of an ecological multiple-group and time-trend design covering 2458 Brazilian municipalities. The main independent variable was BFP coverage and the outcome was the TB incidence rate. All study variables were obtained from national databases. We used fixed-effects negative binomial models for panel data adjusted for selected covariates and a variable representing time. After controlling for covariates, TB incidence rates were significantly reduced in municipalities with high BFP coverage compared with those with low and intermediate coverage (in a model with a time variable incidence rate ratio = 0.96, 95%CI 0.93-0.99). This was the first evidence of a statistically significant association between the increase in cash transfer programme coverage and a reduction in TB incidence rate. Our findings provide support for social protection interventions for tackling TB worldwide.

  10. Upgraded Fast Beam Conditions Monitor for CMS online luminosity measurement

    CERN Document Server

    Leonard, Jessica Lynn; Hempel, Maria; Henschel, Hans; Karacheban, Olena; Lange, Wolfgang; Lohmann, Wolfgang; Novgorodova, Olga; Penno, Marek; Walsh, Roberval; Dabrowski, Anne; Guthoff, Moritz; Loos, R; Ryjov, Vladimir; Burtowy, Piotr; Lokhovitskiy, Arkady; Odell, Nathaniel; Przyborowski, Dominik; Stickland, David P; Zagozdzinska, Agnieszka

    2014-01-01

    The CMS beam condition monitoring subsystem BCM1F during LHC Run I consisted of 8 individual diamond sensors situated around the beam pipe within the tracker detector volume, for the purpose of fast monitoring of beam background and collision products. Effort is ongoing to develop the use of BCM1F as an online bunch-by-bunch luminosity monitor. BCM1F will be running whenever there is beam in LHC, and its data acquisition is independent from the data acquisition of the CMS detector, hence it delivers luminosity even when CMS is not taking data. To prepare for the expected increase in the LHC luminosity and the change from 50 ns to 25 ns bunch separation, several changes to the system are required, including a higher number of sensors and upgraded electronics. In particular, a new real-time digitizer with large memory was developed and is being integrated into a multi-subsystem framework for luminosity measurement. Current results from Run II preparation will be discussed, including results from the January 201...

  11. Argon Beam Coagulator in Breast Surgery: Effect on the Incidence of Breast Seroma.

    Science.gov (United States)

    Lefemine, Valentina; Cornish, Julie A; Abou-Samra, Walid

    2011-12-01

    Although Argon Beam Coagulators (ABCs) are widely used in urological and gynecological procedures, there have been only two studies published so far on their use and benefits in breast surgery. This study compares the incidence of breast seroma following mastectomy upon the use of ABC versus standard monopolar diathermy. This is a retrospective cohort study, with data collected from January 2006 to August 2008 for all patients who underwent a simple mastectomy and axillary surgery. Outcomes included incidence of seroma, amount of drainage on day of discharge, and timing of seroma formation. Fifty-six patients were studied, with 30 undergoing simple mastectomy using ABC diathermy and 25 using simple diathermy. The incidence of postoperative breast seroma development was 30% (n = 9) in the former group and 36% (n = 9) in the latter. In the ABC group, a high postoperative drainage at discharge was predictive of developing a seroma; this was not observed in the monopolar group. The search for methods to reduce the incidence of seroma in breast surgery is ongoing worldwide. Despite a previous report, this study failed to show any significant difference between ABC and monopolar diathermy in the incidence of breast seroma formation following simple mastectomy and axillary surgery. ABC diathermy is more costly, and its use needs to be carefully considered in an era of a stretched National Health Service financial budget.

  12. Technical Note: On the impact of the incident electron beam energy on the primary dose component of flattening filter free photon beams.

    Science.gov (United States)

    Kuess, Peter; Georg, Dietmar; Palmans, Hugo; Lechner, Wolfgang

    2016-08-01

    For commercially available linear accelerators (Linacs), the electron energies of flattening filter free (FFF) and flattened (FF) beams are either identical or the electron energy of the FFF beam is increased to match the percentage depth dose curve (PDD) of the FF beam (in reference geometry). This study focuses on the primary dose components of FFF beams for both kinds of settings, studied on the same Linac. The measurements were conducted on a VersaHD Linac (Elekta, Crawley, UK) for both FF and FFF beams with nominal energies of 6 and 10 MV. In the clinical setting of the VersaHD, the energy of FFFM (Matched) beams is set to match the PDDs of the FF beams. In contrast the incident electron beam of the FFFU beam was set to the same energy as for the FF beam. Half value layers (HVLs) and a dual parameter beam quality specifier (DPBQS) were determined. For the 6 MV FFFM beam, HVL and DPBQS values were very similar compared to those of the 6 MV FF beam, while for the 10 MV FFFM and FF beams, only %dd(10)x and HVL values were comparable (differences below 1.5%). This shows that matching the PDD at one depth does not guarantee other beam quality dependent parameters to be matched. For FFFU beams, all investigated beam quality specifiers were significantly different compared to those for FF beams of the same nominal accelerator potential. The DPBQS of the 6 MV FF and FFFM beams was equal within the measurement uncertainty and was comparable to published data of a machine with similar TPR20,10 and %dd(10)x. In contrast to that, the DPBQS's two parameters of the 10 MV FFFM beam were substantially higher compared to those for the 10 MV FF beam. PDD-matched FF and FFF beams of both nominal accelerator potentials were observed to have similar HVL values, indicating similarity of their primary dose components. Using the DPBQS revealed that the mean attenuation coefficient was found to be the same within the uncertainty of 0.8% for 6 MV FF and 6 MV FFFM beams, while for 10 MV

  13. Technical Note: On the impact of the incident electron beam energy on the primary dose component of flattening filter free photon beams

    International Nuclear Information System (INIS)

    Kuess, Peter; Georg, Dietmar; Lechner, Wolfgang; Palmans, Hugo

    2016-01-01

    Purpose: For commercially available linear accelerators (Linacs), the electron energies of flattening filter free (FFF) and flattened (FF) beams are either identical or the electron energy of the FFF beam is increased to match the percentage depth dose curve (PDD) of the FF beam (in reference geometry). This study focuses on the primary dose components of FFF beams for both kinds of settings, studied on the same Linac. Methods: The measurements were conducted on a VersaHD Linac (Elekta, Crawley, UK) for both FF and FFF beams with nominal energies of 6 and 10 MV. In the clinical setting of the VersaHD, the energy of FFF M (Matched) beams is set to match the PDDs of the FF beams. In contrast the incident electron beam of the FFF U beam was set to the same energy as for the FF beam. Half value layers (HVLs) and a dual parameter beam quality specifier (DPBQS) were determined. Results: For the 6 MV FFF M beam, HVL and DPBQS values were very similar compared to those of the 6 MV FF beam, while for the 10 MV FFF M and FF beams, only %dd(10) x and HVL values were comparable (differences below 1.5%). This shows that matching the PDD at one depth does not guarantee other beam quality dependent parameters to be matched. For FFF U beams, all investigated beam quality specifiers were significantly different compared to those for FF beams of the same nominal accelerator potential. The DPBQS of the 6 MV FF and FFF M beams was equal within the measurement uncertainty and was comparable to published data of a machine with similar TPR 20,10 and %dd(10) x . In contrast to that, the DPBQS’s two parameters of the 10 MV FFF M beam were substantially higher compared to those for the 10 MV FF beam. Conclusions: PDD-matched FF and FFF beams of both nominal accelerator potentials were observed to have similar HVL values, indicating similarity of their primary dose components. Using the DPBQS revealed that the mean attenuation coefficient was found to be the same within the uncertainty of

  14. Relating coccidioidomycosis (valley fever) incidence to soil moisture conditions.

    Science.gov (United States)

    Coopersmith, E J; Bell, J E; Benedict, K; Shriber, J; McCotter, O; Cosh, M H

    2017-04-17

    Coccidioidomycosis (also called Valley fever) is caused by a soilborne fungus, Coccidioides spp. , in arid regions of the southwestern United States. Though some who develop infections from this fungus remain asymptomatic, others develop respiratory disease as a consequence. Less commonly, severe illness and death can occur when the infection spreads to other regions of the body. Previous analyses have attempted to connect the incidence of coccidioidomycosis to broadly available climatic measurements, such as precipitation or temperature. However, with the limited availability of long-term, in situ soil moisture data sets, it has not been feasible to perform a direct analysis of the relationships between soil moisture levels and coccidioidomycosis incidence on a larger temporal and spatial scale. Utilizing in situ soil moisture gauges throughout the southwest from the U.S. Climate Reference Network and a model with which to extend those estimates, this work connects periods of higher and lower soil moisture in Arizona and California between 2002 and 2014 to the reported incidence of coccidioidomycosis. The results indicate that in both states, coccidioidomycosis incidence is related to soil moisture levels from previous summers and falls. Stated differently, a higher number of coccidioidomycosis cases are likely to be reported if previous bands of months have been atypically wet or dry, depending on the location.

  15. 77 FR 32006 - Special Conditions: Gulfstream Model GVI Airplane; High Incidence Protection

    Science.gov (United States)

    2012-05-31

    ... Special Conditions No. 25-423-SC] Special Conditions: Gulfstream Model GVI Airplane; High Incidence... pertaining to a high incidence protection system that replaces the stall warning system during normal... the condition existing in the test or performance standard in which V SR is being used. (3) The weight...

  16. Cumulative percent energy deposition of photon beam incident on different targets, simulated by Monte Carlo

    International Nuclear Information System (INIS)

    Kandic, A.; Jevremovic, T.; Boreli, F.

    1989-01-01

    Monte Carlo simulation (without secondary radiation) of the standard photon interactions (Compton scattering, photoelectric absorption and pair protection) for the complex slab's geometry is used in numerical code ACCA. A typical ACCA run will yield: (a) transmission of primary photon radiation differential in energy, (b) the spectrum of energy deposited in the target as a function of position and (c) the cumulative percent energy deposition as a function of position. A cumulative percent energy deposition of photon monoenergetic beam incident on simplest and complexity tissue slab and Fe slab are presented in this paper. (author). 5 refs.; 2 figs

  17. Maximum dose angle for oblique incidence on primary beam protective barriers in the design of medical radiation therapy facilities

    International Nuclear Information System (INIS)

    Fondevila, Damian; Arbiser, Silvio; Sansogne, Rosana; Brunetto, Monica; Dosoretz, Bernardo

    2008-01-01

    Primary barrier determinations for the shielding of medical radiation therapy facilities are generally made assuming normal beam incidence on the barrier, since this is geometrically the most unfavorable condition for that shielding barrier whenever the occupation line is allowed to run along the barrier. However, when the occupation line (for example, the wall of an adjacent building) runs perpendicular to the barrier (especially roof barrier), then two opposing factors come in to play: increasing obliquity angle with respect to the barrier increases the attenuation, while the distance to the calculation point decreases, hence, increasing the dose. As a result, there exists an angle (α max ) for which the equivalent dose results in a maximum, constituting the most unfavorable geometric condition for that shielding barrier. Based on the usual NCRP Report No. 151 model, this article presents a simple formula for obtaining α max , which is a function of the thickness of the barrier (t E ) and the equilibrium tenth-value layer (TVL e ) of the shielding material for the nominal energy of the beam. It can be seen that α max increases for increasing TVL e (hence, beam energy) and decreases for increasing t E , with a range of variation that goes from 13 to 40 deg for concrete barriers thicknesses in the range of 50-300 cm and most commercially available teletherapy machines. This parameter has not been calculated in the existing literature for radiotherapy facilities design and has practical applications, as in calculating the required unoccupied roof shielding for the protection of a nearby building located in the plane of the primary beam rotation

  18. Maximum dose angle for oblique incidence on primary beam protective barriers in the design of medical radiation therapy facilities.

    Science.gov (United States)

    Fondevila, Damián; Arbiser, Silvio; Sansogne, Rosana; Brunetto, Mónica; Dosoretz, Bernardo

    2008-05-01

    Primary barrier determinations for the shielding of medical radiation therapy facilities are generally made assuming normal beam incidence on the barrier, since this is geometrically the most unfavorable condition for that shielding barrier whenever the occupation line is allowed to run along the barrier. However, when the occupation line (for example, the wall of an adjacent building) runs perpendicular to the barrier (especially roof barrier), then two opposing factors come in to play: increasing obliquity angle with respect to the barrier increases the attenuation, while the distance to the calculation point decreases, hence, increasing the dose. As a result, there exists an angle (alpha(max)) for which the equivalent dose results in a maximum, constituting the most unfavorable geometric condition for that shielding barrier. Based on the usual NCRP Report No. 151 model, this article presents a simple formula for obtaining alpha(max), which is a function of the thickness of the barrier (t(E)) and the equilibrium tenth-value layer (TVL(e)) of the shielding material for the nominal energy of the beam. It can be seen that alpha(max) increases for increasing TVL(e) (hence, beam energy) and decreases for increasing t(E), with a range of variation that goes from 13 to 40 deg for concrete barriers thicknesses in the range of 50-300 cm and most commercially available teletherapy machines. This parameter has not been calculated in the existing literature for radiotherapy facilities design and has practical applications, as in calculating the required unoccupied roof shielding for the protection of a nearby building located in the plane of the primary beam rotation.

  19. Correction of experimental photon pencil-beams for the effects of non-uniform and non-parallel measurement conditions

    International Nuclear Information System (INIS)

    Ceberg, Crister P.; Bjaerngard, Bengt E.

    1995-01-01

    An approximate experimental determination of photon pencil-beams can be based on the reciprocity theorem. The scatter part of the pencil-beam is then essentially the derivative with respect to the field radius of measured scatter-to-primary ratios in circular fields. Obtained in this way, however, the pencil-beam implicitly carries the influence from the lateral fluence and beam quality variations of the incident photons, as well as the effects of the divergence of the beam. In this work we show how these effects can be corrected for. The procedure was to calculate scatter-to-primary ratios using an analytical expression for the pencil-beam. By disregarding one by one the effects of the divergence and the fluence and beam quality variations, the influence of these effects were separated and quantified. For instance, for a 6 MV beam of 20x20 cm 2 field size, at 20 cm depth and a source distance of 100 cm, the total effect was 3.9%; 2.0% was due to the non-uniform incident profile, 1.0% due to the non-uniform beam quality, and 0.9% due to the divergence of the beam. At a source distance of 400 cm, all these effects were much lower, adding up to a total of 0.3 %. Using calculated correction factors like these, measured scatter-to-primary ratios were then stripped from the effects of non-uniform and non-parallel measurement conditions, and the scatter part of the pencil-beam was determined using the reciprocity theorem without approximations

  20. 75 FR 80735 - Special Conditions: Gulfstream Model GVI Airplane; High Incidence Protection

    Science.gov (United States)

    2010-12-23

    ... Special Conditions No. 25-10-03-SC] Special Conditions: Gulfstream Model GVI Airplane; High Incidence... airworthiness standards for transport category airplanes associated with the use of high incidence protection... transport airplane with an executive cabin interior. The maximum takeoff weight will be 99,600 pounds, with...

  1. 76 FR 17022 - Special Conditions: Gulfstream Model GVI Airplane; High Incidence Protection

    Science.gov (United States)

    2011-03-28

    ... Special Conditions No. 25-423-SC] Special Conditions: Gulfstream Model GVI Airplane; High Incidence... for transport category airplanes associated with the use of high incidence protection. The applicable... with an executive cabin interior. The maximum takeoff weight will be 99,600 pounds, with a maximum...

  2. Human Q fever incidence is associated to spatiotemporal environmental conditions

    NARCIS (Netherlands)

    Van Leuken, J. P G; Swart, A. N.; Brandsma, J.; Terink, W.; Van de Kassteele, J.; Droogers, P.; Sauter, F.; Havelaar, A. H.|info:eu-repo/dai/nl/072306122; Van der Hoek, W.

    2016-01-01

    Airborne pathogenic transmission from sources to humans is characterised by atmospheric dispersion and influence of environmental conditions on deposition and reaerosolisation. We applied a One Health approach using human, veterinary and environmental data regarding the 2009 epidemic in The

  3. Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

    Energy Technology Data Exchange (ETDEWEB)

    Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

    1987-08-01

    New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs.

  4. Development of highly polished, grazing incidence mirrors for synchrotron radiation beam lines at SSRL

    International Nuclear Information System (INIS)

    Tirsell, K.G.; Berglin, E.J.; Fuchs, B.A.; Holdener, F.R.; Humpal, H.H.; Karpenko, V.P.; Kulkarni, S.; Fantone, S.D.

    1987-08-01

    New platinum-coated grazing incidence mirrors with low surface roughnesses have been developed to focus bending magnet radiation from the SSRL/SLAC SPEAR storage ring on the entrance slits of two Beam Line VIII grating monochromators. The first mirror in the toroidal grating monochromator (TGM) branch is a cooled SiC cylinder capable of absorbing synchrotron radiation power levels of up to 260 watts without excessive distortion. This mirror deflects the beam vertically through a 12/degree/ angle and focuses it sagitally on the TGM entrance slit plane. The second TGM optical element is a fused-silica spherical mirror with a large radius of curvature that deflects the beam vertically through an additional 12/degree/ and focuses it tangentially with 3/1 demagnification. The first mirror in our spherical grating branch is a 5/degree/-vertically deflecting, cooled SiC toroid designed to focus tangentially on the monochromator entrance slits and sagitally in the exit slits. A 4/degree/-deflecting fused silica mirror is used after the exit sites in each beam line to refocus on to the sample. For this application a thin cylinder is bent to approximate an ellipsoid. The mirrors are now installed at SSRL and performance measurements are planned. Qualitatively the focus of the TGM optics at the entrance slit plane appears very good. In this paper we discuss considerations leading to the choice of SiC for each of the two first mirrors. We present highlights of the development of these mirrors with some emphasis on SiC polishing techniques. In addition, the specialized metrology developed to produce the more difficult figure of the toroid will be described. Measured surface roughness and figure results will be presented. 19 refs., 11 figs

  5. Incidence and impact of pain conditions and comorbid illnesses

    Directory of Open Access Journals (Sweden)

    Davis JA

    2011-10-01

    Full Text Available Jessica A Davis, Rebecca L Robinson, Trong Kim Le, Jin XieLilly Research Laboratories, Eli Lilly and Company, Indianapolis, IN, USABackground: Individuals with pain often present with more than one painful condition. The purpose of this study was to characterize the rates of comorbidity, pain medication use, and health care costs for 23 selected pain conditions in a large health plan using administrative claims data from 2005 to 2007.Methods: Eligible patients included 1,211,483 adults with at least one pain condition during the one-year study period. Pain condition cohorts were classified based on the first diagnosis present in the claims during the study period.Results: Musculoskeletal pain conditions were among the most prevalent cohorts including low back pain, osteoarthritis, and fibromyalgia. Cancer pain was the least prevalent cohort. Conditions with the lowest illness severity included migraine and painful bladder syndrome cohorts, while cohorts with diabetic neuropathy, human immunodeficiency virus (HIV-associated pain, and cancer pain were the most severe. Across cohorts, the mean number of comorbid pain conditions ranged from 1.39 (for cancer pain and migraine to 2.65 (for multiple sclerosis pain. High rates of mental health conditions were found in cohorts with HIV-associated pain and multiple sclerosis pain (42.59% and 34.78% and were lowest among cohorts with rheumatoid arthritis and psoriatic arthropathy (12.73% and 13.31%, respectively. Rates of sleep disorders ranged from 5.47% (for painful bladder syndrome to 11.59% (for multiple sclerosis pain. Overall, patients averaged 3.53 unique pain medications during the study period. Considerable annual total health care costs were observed in the cancer pain cohort and the lowest costs were observed in the postherpetic neuropathy, surgically-induced pain, migraine, and irritable bowel syndrome cohorts. Costs attributed to pain were highest among the multiple sclerosis, HIV, and cancer

  6. Atomic spin resonance in a rubidium beam obliquely incident to a transmission magnetic grating

    International Nuclear Information System (INIS)

    Hatakeyama, A; Goto, K

    2016-01-01

    We studied atomic spin resonance induced by atomic motion in a spatially periodic magnetostatic field. A rubidium atomic beam, with a velocity of about 400 m s −1 , was obliquely incident to a transmission magnetic grating that produced a spatially periodic magnetic field. The magnetic grating was formed by a magnetic thin film on a polyimide substrate that had multiple slits at 150 μm intervals. The atoms experienced field oscillation, depending on their velocity and the field period when passing through the grating, and underwent magnetic resonance. Resonance spectra obtained with a perpendicular magnetization film were in clear contrast to ones obtained with an in-plane magnetization film. The former exhibited resonance peaks at odd multiples of the frequency, determined by the velocity over the period, while the latter had dips at the same frequencies. (paper)

  7. Detailed characterisation of the incident neutron beam on the TOSCA spectrometer

    Science.gov (United States)

    Pinna, Roberto S.; Rudić, Svemir; Capstick, Matthew J.; McPhail, David J.; Pooley, Daniel E.; Howells, Gareth D.; Gorini, Giuseppe; Fernandez-Alonso, Felix

    2017-10-01

    We report a detailed characterisation of the incident neutron beam on the TOSCA spectrometer. A bespoke time-of-flight neutron monitor has been designed, constructed and used to perform extensive spatially resolved measurements of the absolute neutron flux and its underlying time structure at the instrument sample position. The obtained data give a quantitative understanding of the current instrument beyond neutronic simulations and provide a baseline in order to assess the performance of the upgraded instrument. At an average proton current-on-target of 153 μA (ISIS Target Station 1; at the time of measurements) we have found that the wavelength-integrated neutron flux (from 0.28 Å to 4.65 Å) at the position of the TOSCA instrument sample (spatially averaged across the 3 × 3cm2 surface centred around (0,0) position) is approximately 1 . 2 × 106 neutrons cm-2s-1, while the whole beam has a homogeneous distribution across the 3 . 0 × 3 . 5cm2 sample surface. The spectra reproduced the well-known shape of the neutrons moderated by the room temperature water moderator and exhibit a neutron flux of 7 . 3 × 105 neutrons cm-2s-1Å-1 at 1 Å.

  8. Statistical analysis and modelling of weather radar beam propagation conditions in the Po Valley (Italy

    Directory of Open Access Journals (Sweden)

    A. Fornasiero

    2006-01-01

    Full Text Available Ground clutter caused by anomalous propagation (anaprop can affect seriously radar rain rate estimates, particularly in fully automatic radar processing systems, and, if not filtered, can produce frequent false alarms. A statistical study of anomalous propagation detected from two operational C-band radars in the northern Italian region of Emilia Romagna is discussed, paying particular attention to its diurnal and seasonal variability. The analysis shows a high incidence of anaprop in summer, mainly in the morning and evening, due to the humid and hot summer climate of the Po Valley, particularly in the coastal zone. Thereafter, a comparison between different techniques and datasets to retrieve the vertical profile of the refractive index gradient in the boundary layer is also presented. In particular, their capability to detect anomalous propagation conditions is compared. Furthermore, beam path trajectories are simulated using a multilayer ray-tracing model and the influence of the propagation conditions on the beam trajectory and shape is examined. High resolution radiosounding data are identified as the best available dataset to reproduce accurately the local propagation conditions, while lower resolution standard TEMP data suffers from interpolation degradation and Numerical Weather Prediction model data (Lokal Model are able to retrieve a tendency to superrefraction but not to detect ducting conditions. Observing the ray tracing of the centre, lower and upper limits of the radar antenna 3-dB half-power main beam lobe it is concluded that ducting layers produce a change in the measured volume and in the power distribution that can lead to an additional error in the reflectivity estimate and, subsequently, in the estimated rainfall rate.

  9. Dynamic grazing incidence fast atom diffraction during molecular beam epitaxial growth of GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Atkinson, P., E-mail: atkinson@insp.jussieu.fr; Eddrief, M. [Sorbonne Universités, UPMC Univ. Paris 06, UMR 7588, INSP, F-75005 Paris (France); CNRS, UMR 7588, Institut des NanoSciences de Paris, 4 place Jussieu, F-75005 Paris (France); Etgens, V. H. [CNRS, UMR 7588, Institut des NanoSciences de Paris, 4 place Jussieu, F-75005 Paris (France); VeDeCom-Université Versailles Saint-Quentin en Yvelines, Versailles (France); Khemliche, H., E-mail: hocine.khemliche@u-psud.fr; Debiossac, M.; Mulier, M.; Lalmi, B.; Roncin, P. [ISMO UMR8214 CNRS-Université Paris-Sud, Orsay F-91400 (France); Momeni, A. [ISMO UMR8214 CNRS-Université Paris-Sud, Orsay F-91400 (France); Univ. Cergy Pontoise, F-95031 Cergy (France)

    2014-07-14

    A Grazing Incidence Fast Atom Diffraction (GIFAD) system has been mounted on a commercial molecular beam epitaxy chamber and used to monitor GaAs growth in real-time. In contrast to the conventionally used Reflection High Energy Electron Diffraction, all the GIFAD diffraction orders oscillate in phase, with the change in intensity related to diffuse scattering at step edges. We show that the scattered intensity integrated over the Laue circle is a robust method to monitor the periodic change in surface roughness during layer-by-layer growth, with oscillation phase and amplitude independent of incidence angle and crystal orientation. When there is a change in surface reconstruction at the start of growth, GIFAD intensity oscillations show that there is a corresponding delay in the onset of layer-by-layer growth. In addition, changes in the relative intensity of different diffraction orders have been observed during growth showing that GIFAD has the potential to provide insight into the preferential adatom attachment sites on the surface reconstruction during growth.

  10. Popular heavy particle beam cancer therapeutic system (3). Development of high efficiency compact incident system-2. Great success of beam test of new APF-IH type DTL

    International Nuclear Information System (INIS)

    Yamamoto, Kazuo; Iwata, Yoshiyuki

    2006-01-01

    High efficiency compact incident system consists of an electron cyclotron resonance (ECR) ion source, a radio frequency quadrupole (RFQ) linear accelerator and an interdigital H-mode (IH) drift tube linear accelerator (DTL). IH type DTL and alternating phase focusing (APF) method is explained. Its special features, production, and beam test are reported. The electric field generation method, outline of the APF method, drift tube, IH type DTL, distribution of electric field and voltage, set up of beam test, ECR ion source and incident line, the inside structure of the RFQ type linear accelerator and the APF-IH type DTL, matching Q lens section, beam, emittance, measurement results of momentum dispersion are illustrated. (S.Y.)

  11. Malfunctions of Implantable Cardiac Devices in Patients Receiving Proton Beam Therapy: Incidence and Predictors

    International Nuclear Information System (INIS)

    Gomez, Daniel R.; Poenisch, Falk; Pinnix, Chelsea C.; Sheu, Tommy; Chang, Joe Y.; Memon, Nada; Mohan, Radhe; Rozner, Marc A.; Dougherty, Anne H.

    2013-01-01

    Purpose: Photon therapy has been reported to induce resets of implanted cardiac devices, but the clinical sequelae of treating patients with such devices with proton beam therapy (PBT) are not well known. We reviewed the incidence of device malfunctions among patients undergoing PBT. Methods and Materials: From March 2009 through July 2012, 42 patients with implanted cardiac implantable electronic devices (CIED; 28 pacemakers and 14 cardioverter-defibrillators) underwent 42 courses of PBT for thoracic (23, 55%), prostate (15, 36%), liver (3, 7%), or base of skull (1, 2%) tumors at a single institution. The median prescribed dose was 74 Gy (relative biological effectiveness; range 46.8-87.5 Gy), and the median distance from the treatment field to the CIED was 10 cm (range 0.8-40 cm). Maximum proton and neutron doses were estimated for each treatment course. All CIEDs were checked before radiation delivery and monitored throughout treatment. Results: Median estimated peak proton and neutron doses to the CIED in all patients were 0.8 Gy (range 0.13-21 Gy) and 346 Sv (range 11-1100 mSv). Six CIED malfunctions occurred in 5 patients (2 pacemakers and 3 defibrillators). Five of these malfunctions were CIED resets, and 1 patient with a defibrillator (in a patient with a liver tumor) had an elective replacement indicator after therapy that was not influenced by radiation. The mean distance from the proton beam to the CIED among devices that reset was 7.0 cm (range 0.9-8 cm), and the mean maximum neutron dose was 655 mSv (range 330-1100 mSv). All resets occurred in patients receiving thoracic PBT and were corrected without clinical incident. The generator for the defibrillator with the elective replacement indicator message was replaced uneventfully after treatment. Conclusions: The incidence of CIED resets was about 20% among patients receiving PBT to the thorax. We recommend that PBT be avoided in pacing-dependent patients and that patients with any type of CIED receiving

  12. Effect of beam condition in variable-shaped electron-beam direct writing for 0.25 μm and below

    International Nuclear Information System (INIS)

    Hirasawa, S.; Nakajima, K.; Tamura, T.; Aizaki, N.

    1993-01-01

    The effect of incident electron-beam conditions, which are acceleration voltage and beam blur of variable-shaped electron-beam direct writing, is investigated using the deposited energy distribution to realize a fine pattern of ≤0.25 μm in trilayer resist process. The deposited energy distribution is calculated using a three-dimensional Monte Carlo method. In a trilayer resist system, a thin bottom resist layer can be used, because the contrast value derived from the Monte Carlo calculation is independent of the bottom layer thickness. The beam blur of 0.05 μm does not degrade 0.25 μm line-and-space (L/S) patterns, but seriously degrades 0.1 μm L/S patterns. Higher acceleration voltage is effective for improving the contrast. At lower acceleration voltage, the slope of the deposited energy profile defined at the resist bottom is mainly influenced by electron scattering. On the other hand, at higher acceleration voltage, the slope of deposited energy profile mainly depends on the beam blur. The 0.1 μm L/S patterns are expected to be resolved at 30 kV when there is less than 0.02 μm beam blur with trilayer resist system. The possibility of using a single layer resist process for 0.1 μm L/S pattern will be barely realized at the conditions of 50 kV and 0.02 μm beam blur

  13. Fast beam conditions monitor BCM1F for the CMS experiment

    International Nuclear Information System (INIS)

    Bell, A.; Castro, E.; Hall-Wilton, R.

    2009-10-01

    The CMS Beam Conditions and Radiation Monitoring System, BRM, will support beam tuning, protect the CMS detector from adverse beam conditions, and measure the accumulated dose close to or inside all sub-detectors. It is composed of different sub-systems measuring either the particle flux near the beam pipe with time resolution between nano- and microseconds or the integrated dose over longer time intervals. This paper presents the Fast Beam Conditions Monitor, BCM1F, which is designed for fast flux monitoring measuring both beam halo and collision products. BCM1F is located inside the CMS pixel detector volume close to the beam-pipe. It uses sCVD diamond sensors and radiation hard front-end electronics, along with an analog optical readout of the signals. The commissioning of the system and its successful operation during the first beams of the LHC are described. (orig.)

  14. Fast beam conditions monitor BCM1F for the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Bell, A. [CERN, Geneva (Switzerland); Geneva Univ. (Switzerland); Castro, E. [DESY Zeuthen (Germany); Hall-Wilton, R. [CERN, Geneva (Switzerland); Wisconsin Univ., Madison, WI (US)] (and others)

    2009-10-15

    The CMS Beam Conditions and Radiation Monitoring System, BRM, will support beam tuning, protect the CMS detector from adverse beam conditions, and measure the accumulated dose close to or inside all sub-detectors. It is composed of different sub-systems measuring either the particle flux near the beam pipe with time resolution between nano- and microseconds or the integrated dose over longer time intervals. This paper presents the Fast Beam Conditions Monitor, BCM1F, which is designed for fast flux monitoring measuring both beam halo and collision products. BCM1F is located inside the CMS pixel detector volume close to the beam-pipe. It uses sCVD diamond sensors and radiation hard front-end electronics, along with an analog optical readout of the signals. The commissioning of the system and its successful operation during the first beams of the LHC are described. (orig.)

  15. The influence of incident beam's angle offset of Fourier transform infrared spectrometer on the spectrum measurement explored with synchrotron radiation

    International Nuclear Information System (INIS)

    Chen Wenhao; Chen Min; Xiao Tiqiao

    2011-01-01

    Effects of the incident angle offset on FT-IR spectra are investigated in this paper. The simulated FT-IR spectra are obtained by Fourier inverse transform. The results show that this frequency shift varies with the angle offset of the incident beam in FT-IR. As an example,the factors that affect the angle of incident IR light at SSRF are analyzed. According to performance specifications of the IR beamline, requirements of the optical component installation precision and position drift of the light source are given. (authors)

  16. Characterisation of the incident beam and current diffraction capabilities on the VESUVIO spectrometer

    Science.gov (United States)

    Romanelli, G.; Krzystyniak, M.; Senesi, R.; Raspino, D.; Boxall, J.; Pooley, D.; Moorby, S.; Schooneveld, E.; Rhodes, N. J.; Andreani, C.; Fernandez-Alonso, F.

    2017-09-01

    The VESUVIO spectrometer at the ISIS pulsed neutron and muon source is a unique instrument amongst those available at neutron facilities. This is the only inverted-geometry neutron spectrometer accessing values of energy and wavevector transfer above tens of eV and {\\mathringA}-1 , respectively, and where deep inelastic neutron scattering experiments are routinely performed. As such, the procedure at the base of the technique has been previously described in an article published by this journal (Mayers and Reiter 2012 Meas. Sci. Technol. 23 045902). The instrument has recently witnessed an upsurge of interest due to a new trend to accommodate, within a single experiment, neutron diffraction and transmission measurements in addition to deep inelastic neutron scattering. This work presents a broader description of the instrument following these recent developments. In particular, we assess the absolute intensity and two-dimensional profile of the incident neutron beam and the capabilities of the backscattering diffraction banks. All results are discussed in the light of recent changes to the moderator viewed by the instrument. We find that VESUVIO has to be considered a high-resolution diffractometer as much as other diffractometers at ISIS, with a resolution as high as 2× 10-3 in backscattering. Also, we describe the extension of the wavelength range of the instrument to include lower neutron energies for diffraction measurements, an upgrade that could be readily applied to other neutron instruments as well.

  17. Dosimetric performance evaluation regarding proton beam incident angles of a lithium-based AB-BNCT design

    International Nuclear Information System (INIS)

    Lee, Pei-Yi; Jiang, Shiang-Huei; Liu, Yuan-Hao

    2014-01-01

    The 7 Li(p,xn) 7 Be nuclear reaction, based on the low-energy protons, could produce soft neutrons for accelerator-based boron neutron capture therapy (AB-BNCT). Based on the fact that the induced neutron field is relatively divergent, the relationship between the incident angle of proton beam and the neutron beam quality was evaluated in this study. To provide an intense epithermal neutron beam, a beam-shaping assembly (BSA) was designed. And a modified Snyder head phantom was used in the calculations for evaluating the dosimetric performance. From the calculated results, the intensity of epithermal neutrons increased with the increase in proton incident angle. Hence, either the irradiation time or the required proton current can be reduced. When the incident angle of 2.5-MeV proton beam is 120 deg., the required proton current is ∼13.3 mA for an irradiation time of half an hour. The results of this study show that the BSA designs can generate neutron beams with good intensity and penetrability. Using a 20-mA, 2.5-MeV proton beam as the source, the required irradiation time, to induce 60 RBE-Gy of maximum tumour dose, is less than half an hour in any proton beam alignments. On the premise that the dosimetric performances are similar, the intensity of epithermal neutrons can be increased by using non-collinear (e.g. 90 deg., 120 deg.) incident protons. Thus, either the irradiation time or the required proton current can be reduced. The use of 120 deg. BSA model shows the possibility to reduce the required proton current to ∼13.3 mA when the goal of irradiation time is 30 min. The decrease of required proton beam current certainly will make the use of lithium target much easier. In June 2013, a 5-MeV, 30-mA radio frequency quadruple (RFQ) accelerator for BNCT was built at INFN-LNL (Legnaro National Laboratories, Italy), which shows a possibility to build a suitable RFQ accelerator for the authors' design. In addition, a 2.5-MeV, 30-mA Tandem accelerator was

  18. New Fast Beam Conditions Monitoring (BCM1F) system for CMS

    Science.gov (United States)

    Zagozdzinska, A. A.; Bell, A. J.; Dabrowski, A. E.; Hempel, M.; Henschel, H. M.; Karacheban, O.; Przyborowski, D.; Leonard, J. L.; Penno, M.; Pozniak, K. T.; Miraglia, M.; Lange, W.; Lohmann, W.; Ryjov, V.; Lokhovitskiy, A.; Stickland, D.; Walsh, R.

    2016-01-01

    The CMS Beam Radiation Instrumentation and Luminosity (BRIL) project is composed of several systems providing the experiment protection from adverse beam conditions while also measuring the online luminosity and beam background. Although the readout bandwidth of the Fast Beam Conditions Monitoring system (BCM1F—one of the faster monitoring systems of the CMS BRIL), was sufficient for the initial LHC conditions, the foreseen enhancement of the beams parameters after the LHC Long Shutdown-1 (LS1) imposed the upgrade of the system. This paper presents the new BCM1F, which is designed to provide real-time fast diagnosis of beam conditions and instantaneous luminosity with readout able to resolve the 25 ns bunch structure.

  19. Influence of body condition on incidence and degree of hepatic lipidosis in cows

    OpenAIRE

    Šamanc Horea; Stojić Velibor; Kirovski Danijela; Jovanović Milijan; Cernescu Horia; Vujanac Ivan; Prodanović Radiša

    2008-01-01

    The aim of this study was to investigate the influence of energy status of cows, estimated by body condition score, on the incidence and the degree of hepatic lipidosis during the early stage of lactation. Cows were divided into four groups: dry, early puerperal, early lactation and late lactation period. Each group consisted of 60 cows. Body condition was scored by the method established in Elaco Animal Health Buletin Al 8478. According to this method, body condition score is represented num...

  20. Short-wavelength soft-x-ray laser pumped in double-pulse single-beam non-normal incidence

    International Nuclear Information System (INIS)

    Zimmer, D.; Ros, D.; Guilbaud, O.; Habib, J.; Kazamias, S.; Zielbauer, B.; Bagnoud, V.; Ecker, B.; Aurand, B.; Kuehl, T.; Hochhaus, D. C.; Neumayer, P.

    2010-01-01

    We demonstrated a 7.36 nm Ni-like samarium soft-x-ray laser, pumped by 36 J of a neodymium:glass chirped-pulse amplification laser. Double-pulse single-beam non-normal-incidence pumping was applied for efficient soft-x-ray laser generation. In this case, the applied technique included a single-optic focusing geometry for large beam diameters, a single-pass grating compressor, traveling-wave tuning capability, and an optimized high-energy laser double pulse. This scheme has the potential for even shorter-wavelength soft-x-ray laser pumping.

  1. Wideband converter of a charge of particle beam incident on a Faraday cylinder into a number of pulses

    International Nuclear Information System (INIS)

    Shchagin, A.V.; Lysenko, V.F.

    1985-01-01

    An electric circuit of a beam positive charge-pulse converter during beam incidence on a Faraday cylinder (conversion of Faraday cylinder current into F frequency, where F=10 10 J, where J - is the Faraday cylinder current) is described. Conversion ratio is 10 10 pulses/KP (10 10 Hz/A). Input current change limits are 10 -10 -10 -4 A. Conversion error is |ΔF| -3 F +0.1 Hz). ''Dead'' time is absent. Input resistance of the converter is close to zero

  2. Reflection and Transmission of a Focused Finite Amplitude Sound Beam Incident on a Curved Interface

    Science.gov (United States)

    Makin, Inder Raj Singh

    Reflection and transmission of a finite amplitude focused sound beam at a weakly curved interface separating two fluid-like media are investigated. The KZK parabolic wave equation, which accounts for thermoviscous absorption, diffraction, and nonlinearity, is used to describe the high intensity focused beam. The first part of the work deals with the quasilinear analysis of a weakly nonlinear beam after its reflection and transmission from a curved interface. A Green's function approach is used to define the field integrals describing the primary and the nonlinearly generated second harmonic beam. Closed-form solutions are obtained for the primary and second harmonic beams when a Gaussian amplitude distribution at the source is assumed. The second part of the research uses a numerical frequency domain solution of the KZK equation for a fully nonlinear analysis of the reflected and transmitted fields. Both piston and Gaussian sources are considered. Harmonic components generated in the medium due to propagation of the focused beam are evaluated, and formation of shocks in the reflected and transmitted beams is investigated. A finite amplitude focused beam is observed to be modified due to reflection and transmission from a curved interface in a manner distinct from that in the case of a small signal beam. Propagation curves, beam patterns, phase plots and time waveforms for various parameters defining the source and media pairs are presented, highlighting the effect of the interface curvature on the reflected and transmitted beams. Relevance of the current work to biomedical applications of ultrasound is discussed.

  3. Upgraded Fast Beam Conditions Monitor for CMS online luminosity measurement

    CERN Document Server

    Leonard, Jessica Lynn

    2014-01-01

    The CMS beam and radiation monitoring subsystem BCM1F during LHC Run I consisted of 8 individual diamond sensors situated around the beam pipe within the tracker detector volume, for the purpose of fast monitoring of beam background and collision products. Effort is ongoing to develop the use of BCM1F as an online bunch-by-bunch luminosity monitor. BCM1F will be running whenever there is beam in LHC, and its data acquisition is independent from the data acquisition of the CMS detector, hence it delivers luminosity even when CMS is not taking data. To prepare for the expected increase in the LHC luminosity and the change from 50 ns to 25 ns bunch separation, several changes to the system are required, including a higher number of sensors and upgraded electronics. In particular, a new real-time digitizer with large memory was developed and is being integrated into a multi-subsystem framework for luminosity measurement. Current results from Run II preparation will be shown, including results from the January 201...

  4. Performance and perspectives of the diamond based Beam Condition Monitor for beam loss monitoring at CMS

    CERN Document Server

    AUTHOR|(CDS)2080862

    2015-01-01

    At CMS, a beam loss monitoring system is operated to protect the silicon detectors from high particle rates, arising from intense beam loss events. As detectors, poly-crystalline CVD diamond sensors are placed around the beam pipe at several locations inside CMS. In case of extremely high detector currents, the LHC beams are automatically extracted from the LHC rings.Diamond is the detector material of choice due to its radiation hardness. Predictions of the detector lifetime were made based on FLUKA monte-carlo simulations and irradiation test results from the RD42 collaboration, which attested no significant radiation damage over several years.During the LHC operational Run1 (2010 â?? 2013), the detector efficiencies were monitored. A signal decrease of about 50 times stronger than expectations was observed in the in-situ radiation environment. Electric field deformations due to charge carriers, trapped in radiation induced lattice defects, are responsible for this signal decrease. This so-called polarizat...

  5. Full data consistency conditions for cone-beam projections with sources on a plane

    International Nuclear Information System (INIS)

    Clackdoyle, Rolf; Desbat, Laurent

    2013-01-01

    Cone-beam consistency conditions (also known as range conditions) are mathematical relationships between different cone-beam projections, and they therefore describe the redundancy or overlap of information between projections. These redundancies have often been exploited for applications in image reconstruction. In this work we describe new consistency conditions for cone-beam projections whose source positions lie on a plane. A further restriction is that the target object must not intersect this plane. The conditions require that moments of the cone-beam projections be polynomial functions of the source positions, with some additional constraints on the coefficients of the polynomials. A precise description of the consistency conditions is that the four parameters of the cone-beam projections (two for the detector, two for the source position) can be expressed with just three variables, using a certain formulation involving homogeneous polynomials. The main contribution of this work is our demonstration that these conditions are not only necessary, but also sufficient. Thus the consistency conditions completely characterize all redundancies, so no other independent conditions are possible and in this sense the conditions are full. The idea of the proof is to use the known consistency conditions for 3D parallel projections, and to then apply a 1996 theorem of Edholm and Danielsson that links parallel to cone-beam projections. The consistency conditions are illustrated with a simulation example. (paper)

  6. Dose-volume based ranking of incident beam direction and its utility in facilitating IMRT beam placement

    International Nuclear Information System (INIS)

    Schreibmann, Eduard; Xing Lei

    2005-01-01

    Purpose: Beam orientation optimization in intensity-modulated radiation therapy (IMRT) is computationally intensive, and various single beam ranking techniques have been proposed to reduce the search space. Up to this point, none of the existing ranking techniques considers the clinically important dose-volume effects of the involved structures, which may lead to clinically irrelevant angular ranking. The purpose of this work is to develop a clinically sensible angular ranking model with incorporation of dose-volume effects and to show its utility for IMRT beam placement. Methods and Materials: The general consideration in constructing this angular ranking function is that a beamlet/beam is preferable if it can deliver a higher dose to the target without exceeding the tolerance of the sensitive structures located on the path of the beamlet/beam. In the previously proposed dose-based approach, the beamlets are treated independently and, to compute the maximally deliverable dose to the target volume, the intensity of each beamlet is pushed to its maximum intensity without considering the values of other beamlets. When volumetric structures are involved, the complication arises from the fact that there are numerous dose distributions corresponding to the same dose-volume tolerance. In this situation, the beamlets are not independent and an optimization algorithm is required to find the intensity profile that delivers the maximum target dose while satisfying the volumetric constraints. In this study, the behavior of a volumetric organ was modeled by using the equivalent uniform dose (EUD). A constrained sequential quadratic programming algorithm (CFSQP) was used to find the beam profile that delivers the maximum dose to the target volume without violating the EUD constraint or constraints. To assess the utility of the proposed technique, we planned a head-and-neck and abdominal case with and without the guidance of the angular ranking information. The qualities of the

  7. Structured surface reflector design for oblique incidence beam splitter at 610 GHz

    OpenAIRE

    Defrance , Fabien; Casaletti , Massimiliano; Sarrazin , Julien; Wiedner , Martina; Gibson , Hugh; Gay , Gregory; Lefevre , Roland; Delorme , Yan

    2016-01-01

    International audience; An iterative alternate projection-based algorithm is developed to design structured surface reflectors to operate as beam splitters at GHz and THz frequencies. To validate the method, a surface profile is determined to achieve a reflector at 610 GHz that generates four equal-intensity beams towards desired directions of ±12.6° with respect to the specular reflection axis. A prototype is fabricated and the beam splitter behavior is experimentally demonstrated. Measureme...

  8. Run II performance of luminosity and beam condition monitors at CMS

    Energy Technology Data Exchange (ETDEWEB)

    Leonard, Jessica Lynn [DESY, Hamburg (Germany)

    2016-07-01

    The BRIL (Beam Radiation Instrumentation and Luminosity) system of CMS consists of instrumentation to measure the luminosity online and offline, and to monitor the LHC beam conditions inside CMS. An accurate luminosity measurement is essential to the CMS physics program, and measurement of the beam background is necessary to ensure safe operation of CMS. Many of the BRIL subsystems have been upgraded and others have been added for LHC Run II to complement the existing measurements. The beam condition monitor (BCM) consists of several sets of diamond sensors used to measure online luminosity and beam background with a single-bunch-crossing resolution. The BCM also detects when beam conditions become unfavorable for CMS running and may trigger a beam abort to protect the detector. The beam halo monitor (BHM) uses quartz bars to measure the background of the incoming beams at larger radii. The pixel luminosity telescope (PLT) consists of telescopes of silicon sensors designed to provide a CMS online and offline luminosity measurement. In addition, the forward hadronic calorimeter (HF) delivers an independent luminosity measurement, making the whole system robust and allowing for cross-checks of the systematics. An overview of the performance during 2015 LHC running for the new/updated BRIL subsystems will be given, including the uncertainties of the luminosity measurements.

  9. Explicit formulation for natural frequencies of double-beam system with arbitrary boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mirzabeigy, Alborz; Madoliat, Reza [Iran University of Science and Technology, Narmak, Tehran (Iran, Islamic Republic of); Dabbagh, Vahid [University of Malaya, Kuala Lumpur (Malaysia)

    2017-02-15

    In this paper, free transverse vibration of two parallel beams connected through Winkler type elastic layer is investigated. Euler- Bernoulli beam hypothesis has been applied and it is assumed that boundary conditions of upper and lower beams are similar while arbitrary without any limitation even for non-ideal boundary conditions. Material properties and cross-section geometry of beams could be different from each other. The motion of the system is described by a homogeneous set of two partial differential equations, which is solved by using the classical Bernoulli-Fourier method. Explicit expressions are derived for the natural frequencies. In order to verify accuracy of results, the problem once again solved using modified Adomian decomposition method. Comparison between results indicates excellent accuracy of proposed formulation for any arbitrary boundary conditions. Derived explicit formulation is simplest method to determine natural frequencies of double-beam systems with high level of accuracy in comparison with other methods in literature.

  10. Beam wandering statistics of twin thin laser beam propagation under generalized atmospheric conditions.

    Science.gov (United States)

    Pérez, Darío G; Funes, Gustavo

    2012-12-03

    Under the Geometrics Optics approximation is possible to estimate the covariance between the displacements of two thin beams after they have propagated through a turbulent medium. Previous works have concentrated in long propagation distances to provide models for the wandering statistics. These models are useful when the separation between beams is smaller than the propagation path-regardless of the characteristics scales of the turbulence. In this work we give a complete model for these covariances, behavior introducing absolute limits to the validity of former approximations. Moreover, these generalizations are established for non-Kolmogorov atmospheric models.

  11. Quantitative approach for optimizing e-beam condition of photoresist inspection and measurement

    Science.gov (United States)

    Lin, Chia-Jen; Teng, Chia-Hao; Cheng, Po-Chung; Sato, Yoshishige; Huang, Shang-Chieh; Chen, Chu-En; Maruyama, Kotaro; Yamazaki, Yuichiro

    2018-03-01

    Severe process margin in advanced technology node of semiconductor device is controlled by e-beam metrology system and e-beam inspection system with scanning electron microscopy (SEM) image. By using SEM, larger area image with higher image quality is required to collect massive amount of data for metrology and to detect defect in a large area for inspection. Although photoresist is the one of the critical process in semiconductor device manufacturing, observing photoresist pattern by SEM image is crucial and troublesome especially in the case of large image. The charging effect by e-beam irradiation on photoresist pattern causes deterioration of image quality, and it affect CD variation on metrology system and causes difficulties to continue defect inspection in a long time for a large area. In this study, we established a quantitative approach for optimizing e-beam condition with "Die to Database" algorithm of NGR3500 on photoresist pattern to minimize charging effect. And we enhanced the performance of measurement and inspection on photoresist pattern by using optimized e-beam condition. NGR3500 is the geometry verification system based on "Die to Database" algorithm which compares SEM image with design data [1]. By comparing SEM image and design data, key performance indicator (KPI) of SEM image such as "Sharpness", "S/N", "Gray level variation in FOV", "Image shift" can be retrieved. These KPIs were analyzed with different e-beam conditions which consist of "Landing Energy", "Probe Current", "Scanning Speed" and "Scanning Method", and the best e-beam condition could be achieved with maximum image quality, maximum scanning speed and minimum image shift. On this quantitative approach of optimizing e-beam condition, we could observe dependency of SEM condition on photoresist charging. By using optimized e-beam condition, measurement could be continued on photoresist pattern over 24 hours stably. KPIs of SEM image proved image quality during measurement and

  12. Nonlocal beam models for buckling of nanobeams using state-space method regarding different boundary conditions

    International Nuclear Information System (INIS)

    Sahmani, S.; Ansari, R.

    2011-01-01

    Buckling analysis of nanobeams is investigated using nonlocal continuum beam models of the different classical beam theories namely as Euler-Bernoulli beam theory (EBT), Timoshenko beam theory (TBT), and Levinson beam theory (LBT). To this end, Eringen's equations of nonlocal elasticity are incorporated into the classical beam theories for buckling of nanobeams with rectangular cross-section. In contrast to the classical theories, the nonlocal elastic beam models developed here have the capability to predict critical buckling loads that allowing for the inclusion of size effects. The values of critical buckling loads corresponding to four commonly used boundary conditions are obtained using state-space method. The results are presented for different geometric parameters, boundary conditions, and values of nonlocal parameter to show the effects of each of them in detail. Then the results are fitted with those of molecular dynamics simulations through a nonlinear least square fitting procedure to find the appropriate values of nonlocal parameter for the buckling analysis of nanobeams relevant to each type of nonlocal beam model and boundary conditions analysis

  13. Nonlocal beam models for buckling of nanobeams using state-space method regarding different boundary conditions

    Energy Technology Data Exchange (ETDEWEB)

    Sahmani, S.; Ansari, R. [University of Guilan, Rasht (Iran, Islamic Republic of)

    2011-09-15

    Buckling analysis of nanobeams is investigated using nonlocal continuum beam models of the different classical beam theories namely as Euler-Bernoulli beam theory (EBT), Timoshenko beam theory (TBT), and Levinson beam theory (LBT). To this end, Eringen's equations of nonlocal elasticity are incorporated into the classical beam theories for buckling of nanobeams with rectangular cross-section. In contrast to the classical theories, the nonlocal elastic beam models developed here have the capability to predict critical buckling loads that allowing for the inclusion of size effects. The values of critical buckling loads corresponding to four commonly used boundary conditions are obtained using state-space method. The results are presented for different geometric parameters, boundary conditions, and values of nonlocal parameter to show the effects of each of them in detail. Then the results are fitted with those of molecular dynamics simulations through a nonlinear least square fitting procedure to find the appropriate values of nonlocal parameter for the buckling analysis of nanobeams relevant to each type of nonlocal beam model and boundary conditions analysis.

  14. Association between the incidence of varicella and meteorological conditions in Jinan, Eastern China, 2012-2014.

    Science.gov (United States)

    Yang, Yunqing; Geng, Xingyi; Liu, Xiaoxue; Wang, Weiru; Zhang, Ji

    2016-04-22

    Varicella remains an important public health issue in China. In this study we explored the effect of weather conditions on the incidence of varicella in the temperate city of Jinan, Eastern China during 2012-2014 to inform public health prevention and control measures. Data on reported cases of varicella were obtained from National Notifiable Disease Report System. Meteorological data for the same time period were obtained from the Jinan Meteorological Bureau. A negative binomial regression model was used to assess the relationships between meteorological variables and the incidence of varicella. Given collinearity between average temperature and atmospheric pressure, separate models were constructed: one including average temperature without atmospheric pressure, the other including atmospheric pressure but without average temperature. Both models included relative humidity, wind velocity, rainfall, sunshine, and year as independent variables. Annual incidence rates of varicella were 44.47, 53.69, and 46.81 per 100,000 for 2012, 2013, and 2014, respectively. Each increase of 100 Pa (hPa) in atmospheric pressure was estimated to be associated with an increase in weekly incidence of 3.35 % (95 % CI = 2.94-3.67 %), while a 1 °C rise in temperature was associated with a decrease of 3.44 % (95 % CI = -3.73-3.15 %) in the weekly incidence of varicella. Similarly, a 1 % rise in relative humidity corresponded to a decrease of 0.50 % or 1.00 %, a 1 h rise in sunshine corresponded to an increase of 1.10 % or 0.50 %, and a 1 mm rise in rainfall corresponded to an increase of 0.20 % or 0.30 %, in the weekly incidence of varicella cases, depending on the variable considered in the model. Our findings show that weather factors have a significant influence on the incidence of varicella. Meteorological conditions should be considered as important predictors of varicella incidence in Jinan, Eastern China.

  15. A code to determine the energy distribution, the incident energy and the flux of a beam of light ions into a stack of foils

    International Nuclear Information System (INIS)

    Sonzogni, A.A.; Romo, A.S.M.A.; Frosch, W.R.; Nassiff, S.J.

    1992-01-01

    The stacked-foil technique is one of the most used methods to obtain excitation functions of nuclear reactions using light ions as projectiles. The purpose of this program is the calculation of the energy of the beam in the stack, as well as to obtain the incident energy and the flux of the beam by using monitor excitation functions. (orig.)

  16. Backscatter dose from metallic materials due to obliquely incident high-energy photon beams

    International Nuclear Information System (INIS)

    Nadrowitz, Roger; Feyerabend, Thomas

    2001-01-01

    If metallic material is exposed to ionizing radiation of sufficient high energy, an increase in dose due to backscatter radiation occurs in front of this material. Our purpose in this study was to quantify these doses at variable distances between scattering materials and the detector at axial beam angles between 0 deg. (zero angle in beams eye view) and 90 deg. . Copper, silver and lead sheets embedded in a phantom of perspex were exposed to 10 MV-bremsstrahlung. The detector we developed is based on the fluorescence property of pyromellitic acid (1,2,4,5 benzenetetracarboxylic acid) after exposure to ionizing radiation. Our results show that the additional doses and the corresponding dose distribution in front of the scattering materials depend quantitatively and qualitatively on the beam angle. The backscatter dose increases with varying beam angle from 0 deg. to 90 deg. up to a maximum at 55 deg. for copper and silver. At angles of 0 deg. and 55 deg. the integral backscatter doses over a tissue-equivalent depth of 2 mm are 11.2% and 21.6% for copper and 24% and 28% for silver, respectively. In contrast, in front of lead there are no obvious differences of the measured backscatter doses at angles between 0 deg. and 55 deg. With a further increase of the beam angle from 55 deg. to 90 deg. the backscatter dose decreases steeply for all three materials. In front of copper a markedly lower penetrating depth of the backscattered electrons was found for an angle of 0 deg. compared to 55 deg. This dependence from the beam angle was less pronounced in front of silver and not detectable in front of lead. In conclusion, the dependence of the backscatter dose from the angle between axial beam and scattering material must be considered, as higher scattering doses have to be considered than previously expected. This may have a clinical impact since the surface of metallic implants is usually curved

  17. Backscatter dose from metallic materials due to obliquely incident high-energy photon beams

    Energy Technology Data Exchange (ETDEWEB)

    Nadrowitz, Roger; Feyerabend, Thomas [Medical University of Luebeck, Germany, Department of Radiotherapy and Nuclear Medicine, Ratzeburger Allee 160, Luebeck, D-23538 (Germany)

    2001-06-01

    If metallic material is exposed to ionizing radiation of sufficient high energy, an increase in dose due to backscatter radiation occurs in front of this material. Our purpose in this study was to quantify these doses at variable distances between scattering materials and the detector at axial beam angles between 0 deg. (zero angle in beams eye view) and 90 deg. . Copper, silver and lead sheets embedded in a phantom of perspex were exposed to 10 MV-bremsstrahlung. The detector we developed is based on the fluorescence property of pyromellitic acid (1,2,4,5 benzenetetracarboxylic acid) after exposure to ionizing radiation. Our results show that the additional doses and the corresponding dose distribution in front of the scattering materials depend quantitatively and qualitatively on the beam angle. The backscatter dose increases with varying beam angle from 0 deg. to 90 deg. up to a maximum at 55 deg. for copper and silver. At angles of 0 deg. and 55 deg. the integral backscatter doses over a tissue-equivalent depth of 2 mm are 11.2% and 21.6% for copper and 24% and 28% for silver, respectively. In contrast, in front of lead there are no obvious differences of the measured backscatter doses at angles between 0 deg. and 55 deg. With a further increase of the beam angle from 55 deg. to 90 deg. the backscatter dose decreases steeply for all three materials. In front of copper a markedly lower penetrating depth of the backscattered electrons was found for an angle of 0 deg. compared to 55 deg. This dependence from the beam angle was less pronounced in front of silver and not detectable in front of lead. In conclusion, the dependence of the backscatter dose from the angle between axial beam and scattering material must be considered, as higher scattering doses have to be considered than previously expected. This may have a clinical impact since the surface of metallic implants is usually curved.

  18. Angular Distributions of Sputtered Atoms from Semiconductor Targets at Grazing Ion Beam Incidence Angles

    International Nuclear Information System (INIS)

    Sekowski, M.; Burenkov, A.; Martinez-Limia, A.; Hernandez-Mangas, J.; Ryssel, H.

    2008-01-01

    Angular distributions of ion sputtered germanium and silicon atoms are investigated within this work. Experiments are performed for the case of grazing ion incidence angles, where the resulting angular distributions are asymmetrical with respect to the polar angle of the sputtered atoms. The performed experiments are compared to Monte-Carlo simulations from different programs. We show here an improved model for the angular distribution, which has an additional dependence of the ion incidence angle.

  19. Causal Factors and Adverse Conditions of Aviation Accidents and Incidents Related to Integrated Resilient Aircraft Control

    Science.gov (United States)

    Reveley, Mary S.; Briggs, Jeffrey L.; Evans, Joni K.; Sandifer, Carl E.; Jones, Sharon Monica

    2010-01-01

    The causal factors of accidents from the National Transportation Safety Board (NTSB) database and incidents from the Federal Aviation Administration (FAA) database associated with loss of control (LOC) were examined for four types of operations (i.e., Federal Aviation Regulation Part 121, Part 135 Scheduled, Part 135 Nonscheduled, and Part 91) for the years 1988 to 2004. In-flight LOC is a serious aviation problem. Well over half of the LOC accidents included at least one fatality (80 percent in Part 121), and roughly half of all aviation fatalities in the studied time period occurred in conjunction with LOC. An adverse events table was updated to provide focus to the technology validation strategy of the Integrated Resilient Aircraft Control (IRAC) Project. The table contains three types of adverse conditions: failure, damage, and upset. Thirteen different adverse condition subtypes were gleaned from the Aviation Safety Reporting System (ASRS), the FAA Accident and Incident database, and the NTSB database. The severity and frequency of the damage conditions, initial test conditions, and milestones references are also provided.

  20. A verification scenario of nuclear plus interference scattering effects using neutron incident angle distribution to the wall in beam-injected deuterium plasmas

    International Nuclear Information System (INIS)

    Sugiyama, Shota; Matsuura, Hideaki; Uchiyama, Daisuke; Sawada, Daisuke; Watanabe, Tsuguhiro; Goto, Takuya; Mitarai, Osamu

    2015-01-01

    A verification scenario of knock-on tail formation in the deuteron distribution function due to nuclear plus interference scattering is presented by observing the incident angle distribution of neutrons in a vacuum vessel. Assuming a knock-on tail created in a "3He-beam-injected deuterium plasma, the incident angle distribution and energy spectra of the neutrons produced by fusion reactions between 1-MeV and thermal deuterons are evaluated. The relation between the neutron incident angle to the vacuum vessel and neutron energy is examined in the case of anisotropic neutron emission due to knock-on tail formation in neutral-beam-injected plasmas. (author)

  1. Double-wall IFR cell for conditioning intense relativistic electron beams

    International Nuclear Information System (INIS)

    Myers, M.C.; Meger, R.A.; Murphy, D.P.; Fernsler, R.F.; Hubbard, R.F.; Slinker, S.P.; Weidman, D.J.

    1994-01-01

    An intense relativistic electron beam (IREB) injected into neutral gas in the high pressure regime characteristically propagates in a self-pinched mode but is susceptible to the resistive hose instability. Typically, beam are conditioned for propagation experiments by reducing the perturbations that may excite resistive hose and by adjusting the emittance profile of the beam such that the convective growth of the instability is decreased. The former has been achieved by applying an anharmonic focusing force as the beam is transported through a conducting tube or cell. The latter has been effectively demonstrated by passing the beam through an ion focus regime (IFR) cell which imposes a head to tail beam emittance variations. However, since the physical parameters of the two types of cells are different, conflicts arise when the cells are coupled sequentially. The double-wall IFR cell described here eliminates these interface difficulties by providing the necessary conditions properties in a single cell. The physics and design of the cell will be introduced and parameter variations explored. The conditioning and propagation measurements will be presented and the results of the experiment will be discussed in relation to theory and simulation

  2. A dynamic plasmonic manipulation technique assisted by phase modulation of an incident optical vortex beam

    International Nuclear Information System (INIS)

    Yuan, G H; Wang, Q; Tan, P S; Lin, J; Yuan, X-C

    2012-01-01

    A novel phase modulation method for dynamic manipulation of surface plasmon polaritons (SPPs) with a phase engineered optical vortex (OV) beam illuminating on nanoslits is experimentally demonstrated. Because of the unique helical phase carried by an OV beam, dynamic control of SPP multiple focusing and standing wave generation is realized by changing the OV beam’s topological charge constituent with the help of a liquid-crystal spatial light modulator. Measurement of SPP distributions with near-field scanning optical microscopy showed an excellent agreement with numerical predictions. The proposed phase modulation technique for manipulating SPPs features has seemingly dynamic and reconfigurable advantages, with profound potential for development of SPP coupling, routing, multiplexing and high-resolution imaging devices on plasmonic chips. (paper)

  3. Virtual-anode formation by an intense pulsed ion beam incident upon a magnetic barrier

    International Nuclear Information System (INIS)

    Robertson, S.; Wessel, F.

    1980-01-01

    An intense, pulsed, initially space-charge-neutral ion beam (100 kV, 1 kA, 600 nsec) has been propagated into a transversely oriented magnetic barrier. When the magnetic field is adjusted so that (rho/sub i/rho/sub e/)/sup 1/2/ very-much-less-than a < rho/sub i/, a virtual anode is formed whose potential oscillates at approx.ω/sub p/i about a value near the ion accelerating potential, where a is the transverse beam dimension, ω/sub tsp/i is the ion plasma frequency, and rho/sub e/ and rho/sub i/ are the electron and ion gyroradii. This behavior is similar to that predicted by Poukey and Rostoker for virtual cathodes

  4. Seasonal variation in the incidence of preeclampsia and eclampsia in tropical climatic conditions

    Directory of Open Access Journals (Sweden)

    Subramaniam Vidya

    2007-10-01

    Full Text Available Abstract Background Observational studies have demonstrated various correlations between hypertensive disorders of pregnancy and different weather parameters. We aim to study if a correlation exists between the incidence of eclampsia and pre-eclampsia and various weather parameters in the tropical coastal city of Mumbai which has the distinction of having relatively uniform meteorological variables all throughout the year, except for the monsoon season. Methods We retrospectively analysed data from a large maternity centre in Mumbai, India over a period of 36 months from March 1993 to February 1996, recording the incidence of preeclampsia and eclampsia. Meteorological data was acquired from the regional meteorological centre recording the monthly average temperature, humidity, barometric pressure and rainfall during the study period. Study period was then divided into two climate conditions: monsoon season (June to August and dry season September to May. The incidence of preeclampsia and eclampsia and the meteorological differences between the two seasons were compared. Results Over a 36-month period, a total of 29562 deliveries were recorded, of which 1238 patients developed preeclampsia (4.18% and 34 developed eclampsia (0.11%. The incidence of preeclampsia did not differ between the monsoon and the dry season (4.3% vs. 4.15%, p = 0.5. The incidence of eclampsia was significantly higher in the monsoon (0.2% vs. 0.08%, p = 0.01. The monsoon was significantly cooler (median maximum temperature 30.7°C vs. 32.3°C, p = 0.01, more humid (median relative humidity 85% vs. 70%, p = 0.0008, and received higher rainfall (median 504.9 mm vs. 0.3 mm, p = 0.0002 than the rest of the year. The median barometric pressure (1005 mb during the monsoon season was significantly lower than the rest of the year (1012 mb, p Conclusion In the tropical climate of Mumbai, the incidence of eclampsia is significantly higher in monsoon, when the weather is cooler and

  5. LIPAc personnel protection system for realizing radiation licensing conditions on injector commissioning with deuteron beam

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hiroki, E-mail: takahashi.hiroki@jaea.go.jp [IFMIF/EVEDA Accelerator Group, Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Narita, Takahiro; Kasugai, Atsushi [IFMIF/EVEDA Accelerator Group, Japan Atomic Energy Agency (JAEA), Rokkasho, Aomori (Japan); Kojima, Toshiyuki [Gitec Co. Ltd., Hachinohe, Aomori (Japan); Marqueta, Alvaro; Nishiyama, Koichi [IFMIF/EVEDA Project Team, Rokkasho, Aomori (Japan); Sakaki, Hironao [Quantum Beam Science Center, JAEA, Kizu, Kyoto (Japan); Gobin, Raphael [Commissariat à l’Energie Atomique et aux Energies Alternatives, CEA/Saclay, DSM/IRFU, Gif/Yvette (France)

    2016-11-01

    Highlights: • Personnel Protection System (PPS) is developed to adapt the radiation licensing. • PPS achieves the target performance to secure the personnel safety. • Pulse Duty Management System (PDMS) is developed to manage the beam-operation-time. • Satisfying performance of PDMS is confirmed by injector operation with H+ beam. • By the result of PPS and PDMS tests, the radiation license was successfully obtained. - Abstract: The performance validation of the Linear IFMIF Prototype Accelerator (LIPAc), up to the energy of 9 MeV deuteron beam with 125 mA continuous wave (CW), is planned in Rokkasho, Japan. There are three main phases of LIPAc performance validation: Injector commissioning, RFQ commissioning and LIPAc commissioning. Injector commissioning was started by H{sup +} and D{sup +} beam. To apply the radiation licensing for the Injector commissioning, the entering/leaving to/from accelerator vault should be under control, and access to the accelerator vault has to be prohibited for any person during the beam operation. The Personnel Protection System (PPS) was developed to adapt the radiation licensing conditions. The licensing requests that PPS must manage the accumulated D{sup +} current. So, to manage the overall D{sup +} beam time during injector operation, Pulse Duty Management System (PDMS) was developed as a configurable subsystem as part of the PPS. The PDMS was tested during H{sup +} beam (as simulated D{sup +}) operation, to confirm that it can handle the beam inhibit from Injector before the beam accumulation is above the threshold value specified in the radiation licensing condition. In this paper, the design and configuration of these systems and the result of the tests are presented.

  6. Structural condition assessment and service load performance of deteriorated prestressed concrete deck beam bridges

    Science.gov (United States)

    Fuentes, Juan Bolivar

    Precast pretensioned deck beam bridges are a generic bridge type widely used by IDOT for new construction through the end of the 1970's and still widely used on county roads throughout Illinois. While these bridges were economical to build, IDOT discontinued their use because reflective cracks developed along the length of the longitudinal joints between beams. Three 30 years old deteriorated beams were removed from an existing bridge over Spoon River in Fulton County, IL and delivered to Newmark Civil Engineering Laboratory. The program consisted of a series of comprehensive, destructive and non-destructive, tests and evaluations of the three beams with emphasis on three major areas; (1) The Condition Assessment of the as-delivered beams. (2) The service load performance of the bridge sub-assemblage constructed from those beams. After a comprehensive inspection of the beams was completed, the beams were integrated together into a bridge subassembly that simulated a bridge lane. (3) Following the service load tests, the three beams were separated and tested individually to failure. The critical signs to be observed in existing structures that will lead the inspectors to conclude that a deck beam is being overloaded were are also studied. Several conclusions were found. Cracking of the longitudinal joint has little effect on the stiffness of the bridge if the transverse rod is snug. The presence of a snug transverse tie rod increases the strength of the longitudinal joint. After a longitudinal joint has fractured, reincorporating a snug transverse rod can significantly reestablish the stiffness of the longitudinal joint and reduce overloading of a deteriorated beam. Participation factors must be based on relative bending moments of one beam with respect to the total amount of bending moment produced by the applied load and not to the amount of total vertical displacement. The participation factors will vary along the span of the bridge deck and will depend on the

  7. Influence of body condition on incidence and degree of hepatic lipidosis in cows

    Directory of Open Access Journals (Sweden)

    Šamanc Horea

    2008-01-01

    Full Text Available The aim of this study was to investigate the influence of energy status of cows, estimated by body condition score, on the incidence and the degree of hepatic lipidosis during the early stage of lactation. Cows were divided into four groups: dry, early puerperal, early lactation and late lactation period. Each group consisted of 60 cows. Body condition was scored by the method established in Elaco Animal Health Buletin Al 8478. According to this method, body condition score is represented numerically from 1 to 5 points. Liver samples for pathohistological analyses were taken by biopsy from early lactation cows (60. day of lactation. Fat content in hepatocytes was determined morphometrically and results were compared with criteria based on total lipid and triglyceride content in liver tissue. On farm A, average body condition scores were in a range from 3.31, at sixty days of lactation, to 3.86 points in the dry period. Nevertheless, the range was wider on farm B, and was from 2.18 points at sixty days of lactation to 4.15 points at the dry period. Besides, differences in average body condition scores were higher than 1 point, and in some cases (between late lactation or dry period to sixty days of lactation were almost 2 points. The incidence and the degree of hepatic lipidosis strongly differ between the two examined farms. On farm A the incidence of hepatic lipidosis was 18.33 percent, while on farm B that percent was much higher (43.32. A significant difference was established in the degree of hepatic lipidosis between those two farms. On farm A diffuse hepatic lipidosis was determined in 5.0 percent of cows, while on farm B that percent was 18.33. According to these results, most of the cows on farm B had uncontrolled lipomobilisation and severe fatty liver during the early lactation period, probably due to the obesity of these cows in late lactation and the dry period.

  8. Role of different weather conditions on the incidence and development of american bollworm

    International Nuclear Information System (INIS)

    Khaliq, A.; Subhani, M.N.; Hassan, S.W.; Murtaza, M.A.

    2008-01-01

    Studies were conducted at Nuclear Institute for Agriculture and biology (NIAB). Faisalabad on ten advance genotypes of cotton Viz,. BH-121, NIAB KRISHMA, DNH-137, VH-142, BH-125. MNH-635, SLH-267, FNH-245, CRIS-467 and CRIS-82, to see the role of different weather condition on the incidence and development of American bollworm (Heliothis armigera) infestation and coefficient of correlation among these factors and American bollworm infestation. Trial were laid out using Randomized Complete Block Design (RCBD) with four replications. Finally data were subject to the statistical analysis and for correlation studies between weather factors and percent American boll temperature infestation. Temperature and relative humidity were correlated positively and rainfall effected negatively to the infestation of American bollworm on squares and for green bolls temperature was positively correlated while relative humidity and rainfall negatively with the percent American bollworm infestation in advance -genotypes of cotton under unsprayed condition. (author)

  9. Diamond pad detector telescope for beam conditions and luminosity monitoring in ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Mikuz, M. [Jozef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana (Slovenia)], E-mail: Marko.Mikuz@ijs.si; Cindro, V.; Dolenc, I. [Jozef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana (Slovenia); Frais-Koelbl, H. [University of Applied Sciences Wiener Neustadt and Fotec, Wiener Neustadt (Austria); Gorisek, A. [CERN, Geneva (Switzerland); Griesmayer, E. [University of Applied Sciences Wiener Neustadt and Fotec, Wiener Neustadt (Austria); Kagan, H. [Ohio State University, Columbus (United States); Kramberger, G.; Mandic, I. [Jozef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana (Slovenia); Niegl, M. [University of Applied Sciences Wiener Neustadt and Fotec, Wiener Neustadt (Austria); Pernegger, H. [CERN, Geneva (Switzerland); Trischuk, W. [University of Toronto, Toronto (Canada); Weilhammer, P. [CERN, Geneva (Switzerland); Zavrtanik, M. [Jozef Stefan Institute and Department of Physics, University of Ljubljana, Ljubljana (Slovenia)

    2007-09-01

    Beam conditions and the potential detector damage resulting from their anomalies have pushed the LHC experiments to plan their own monitoring devices in addition to those provided by the machine. ATLAS decided to build a telescope composed of two stations with four diamond pad detector modules each, placed symmetrically around the interaction point at z={+-}183.8cm and r{approx}55mm ({eta}{approx}4.2). Equipped with fast electronics it allows time-of-flight separation of events resulting from beam anomalies from normally occurring p-p interactions. In addition it will provide a coarse measurement of the LHC luminosity in ATLAS. Ten detector modules have been assembled and subjected to tests, from characterization of bare diamonds to source and beam tests. Preliminary results of beam test in the CERN PS indicate a signal-to-noise ratio of 14{+-}2.

  10. Diamond pad detector telescope for beam conditions and luminosity monitoring in ATLAS

    International Nuclear Information System (INIS)

    Mikuz, M.; Cindro, V.; Dolenc, I.; Frais-Koelbl, H.; Gorisek, A.; Griesmayer, E.; Kagan, H.; Kramberger, G.; Mandic, I.; Niegl, M.; Pernegger, H.; Trischuk, W.; Weilhammer, P.; Zavrtanik, M.

    2007-01-01

    Beam conditions and the potential detector damage resulting from their anomalies have pushed the LHC experiments to plan their own monitoring devices in addition to those provided by the machine. ATLAS decided to build a telescope composed of two stations with four diamond pad detector modules each, placed symmetrically around the interaction point at z=±183.8cm and r∼55mm (η∼4.2). Equipped with fast electronics it allows time-of-flight separation of events resulting from beam anomalies from normally occurring p-p interactions. In addition it will provide a coarse measurement of the LHC luminosity in ATLAS. Ten detector modules have been assembled and subjected to tests, from characterization of bare diamonds to source and beam tests. Preliminary results of beam test in the CERN PS indicate a signal-to-noise ratio of 14±2

  11. Quadrupole beam-transport experiment for heavy ions under extreme space charge conditions

    International Nuclear Information System (INIS)

    Chupp, W.; Faltens, A.; Hartwig, E.C.

    1983-03-01

    A Cs ion-beam-transport experiment is in progress to study beam behavior under extreme space-charge conditions. A five-lens section matches the beam into a periodic electrostatic quadrupole FODO channel and its behavior is found to agree with predictions. With the available parameters (less than or equal to 200 keV, less than or equal to 20 mA, πepsilon/sub n/ greater than or equal to 10 - 7 π rad-m, up to 41 periods) the transverse (betatron) occillation frequency (nu) can be depressed down to one-tenth of its zero current value (nu/sub 0/), where nu/sup 2/ = nu/sub 0//sup 2/ -#betta#/sub p/ 2 /2, and #betta#/sub p/ is the beam plasma frequency. The current can be controlled by adjustment of the gun and the emittance can be controlled independently by means of a set of charged grids

  12. LHC Beam Dump Design Study - Part III : Off-normal operating conditions

    CERN Document Server

    Bruno, L; Ross, M; Sala, P

    2000-01-01

    The LHC beam dump design study has been preliminarily substantiated by energy deposition simulations (Part I) and heat transfer analyses (Part II). The present report is devoted to the abnormal operating conditions induced by a malfunction of the beam diluters. A general approach to the analysis of off-normal operation is presented, which is derived from standard design norms adopted in the nuclear industry. Attention is focused mainly on the carbon core, which is longitudinally split into segments of different density in order to better distribute the deposited energy. The maximum energy density it absorbs decreases by at least 33%, compared to a uniform standard density carbon core. This structure may sustain any partial sweep failure without major damage, up to the ultimate beam intensity and energy. To minimise the risks inherent in a fully unswept beam, a sacrificial graphite mandrel will be placed on the core axis, surrounded by a thick high strength carbon-carbon composite tube. With this arrangement, ...

  13. Thermal radiation heat transfer in participating media by finite volume discretization using collimated beam incidence

    Science.gov (United States)

    Harijishnu, R.; Jayakumar, J. S.

    2017-09-01

    The main objective of this paper is to study the heat transfer rate of thermal radiation in participating media. For that, a generated collimated beam has been passed through a two dimensional slab model of flint glass with a refractive index 2. Both Polar and azimuthal angle have been varied to generate such a beam. The Temperature of the slab and Snells law has been validated by Radiation Transfer Equation (RTE) in OpenFOAM (Open Field Operation and Manipulation), a CFD software which is the major computational tool used in Industry and research applications where the source code is modified in which radiation heat transfer equation is added to the case and different radiation heat transfer models are utilized. This work concentrates on the numerical strategies involving both transparent and participating media. Since Radiation Transfer Equation (RTE) is difficult to solve, the purpose of this paper is to use existing solver buoyantSimlpeFoam to solve radiation model in the participating media by compiling the source code to obtain the heat transfer rate inside the slab by varying the Intensity of radiation. The Finite Volume Method (FVM) is applied to solve the Radiation Transfer Equation (RTE) governing the above said physical phenomena.

  14. [Incidence of vitreoretinal pathologic conditions in myopic eyes after laser in situ keratomileusis].

    Science.gov (United States)

    Lin, Jijian; Xie, Xin; Du, Xinhua; Yang, Yabo; Yao, Ke

    2002-09-01

    To determine the incidence of vitreoretinal pathologic conditions in myopic eyes after laser in situ keratomileusis. Vitreoretinal pathologic conditions of 1981 consecutive eyes (995 patients) having undergone laser-assisted in situ keratomileusis for the correction of myopia were studied. Preoperative and postoperative basic examinations included visual acuity, manifest and cycloplegic refraction, slit-lamp microscope examination, applanation tonometry and a fundus examination after pupil dilatation by indirect ophthalmoscopy and biomicroscopy with spherical lens of + 90 diopters. Before laser in situ keratomileusis, preventive treatment was carried out for predisposing lesion of retinal detachment in 8 eyes: 6 eyes for lattice degeneration and 2 eyes for atrophic holes. Postoperative examinations were conducted at 1, 3 and 12 months and once a year thereafter. All eyes were followed up for >/= 12 months. Eyes were followed for a mean of (18.40 +/- 4.50) months (range 12 - 28) after the surgery. Sixteen eyes of 13 patients (0.81%) developed vitreoretinopathy after LASIK, including 6 eyes with lattice degeneration (0.30%) in which one of them had previous laser treatment, 2 with posterior vitreous detachment (0.10%), 2 with macular hemorrhage (0.10%), 4 with rhegmatogenous retinal detachment (0.20%), and 2 with retinal tear without retinal detachment (0.10%) in which one of them had previous laser treatment for lattice degeneration. Five patients were males (5 eyes involved). Others were females. Mean age of the group with vitreoretinal pathologic conditions was 31.80 +/- 5.85 years (range 22 to 43). The interval between refractive surgery and development of vitreoretinal complication was (10.38 +/- 6.20) months (range 1 to 24). The eyes that developed vitreoretinopathy had myopia -4.75 to -15.00 diopters (mean -9.45 +/- 2.61 D) before LASIK. The comparison of incidences of vitreoretinopathy after LASIK between the group of >/= -6.00 D and lattice degeneration and

  15. Constipation--prevalence and incidence among medical patients acutely admitted to hospital with a medical condition.

    Science.gov (United States)

    Noiesen, Eline; Trosborg, Ingelise; Bager, Louise; Herning, Margrethe; Lyngby, Christel; Konradsen, Hanne

    2014-08-01

    To examine the prevalence and incidence of patient-reported symptoms of constipation in acutely hospitalised medical patients. Constipation is a common medical problem with severe consequences, and most people suffer from constipation at some point in their lives. In the general population, constipation is one of the most common complaints and is a significant personal and public health burden. Alteration in patients' patterns of elimination while in hospital has long been identified as either a potential or an actual problem that requires attention. Knowledge of the prevalence and incidence of constipation during hospitalisation is only sporadic. The study was descriptive and a prospective cohort design was chosen. The Constipation Assessment Scale was translated into Danish and was used for the assessment of patient-reported bowel function. Five nurses made the assessments at admission to the acute medical ward and three days after admission. Three hundred and seventy-three patients participated in this study. Thirty-nine percent of the patients showed symptoms of constipation at admission. Of the patients who did not have the symptoms at admission, 43% developed the symptoms during the first three days of their stay in hospital. Significantly more of the older patients developed symptoms of moderate constipation. The incidence rate was 143 new cases per 1000 patient days. In this study, symptoms of constipation were common among patients acutely admitted to hospital due to different medical conditions. Symptoms of constipation were also developed during the first three days of the stay in hospital. The study highlights the need to develop both clinical guidelines towards treating constipation, and preventive measures to ensure that patients do not become constipated while staying in hospital. © 2013 John Wiley & Sons Ltd.

  16. Energy dependence of angular distributions of sputtered particles by ion-beam bombardment at normal incidence

    International Nuclear Information System (INIS)

    Matsuda, Yoshinobu; Ueda, Yasutoshi; Uchino, Kiichiro; Muraoka, Katsunori; Maeda, Mitsuo; Akazaki, Masanori; Yamamura, Yasunori.

    1986-01-01

    The angular distributions of sputtered Fe-atoms were measured using the laser fluorescence technique during Ar-ion bombardment for energies of 0.6, 1, 2 and 3 keV at normal incidence. The measured cosine distribution at 0.6 keV progressively deviated to an over-cosine distribution at higher energies, and at 3 keV the angular distribution was an overcosine distribution of about 20 %. The experimental results agree qualitatively with calculations by a recent computer simulation code, ACAT. The results are explained by the competition between surface scattering and the effects of primary knock-on atoms, which tend to make the angular distributions over-cosine and under-cosine, respectively. (author)

  17. Novel optics for conditioning neutron beams. II Focussing neutrons with a 'lobster-eye' optic

    International Nuclear Information System (INIS)

    Allman, B.E.; Cimmino, A.; Griffin, S.L.; Klein, A.G.; Nugent, K.A.

    1998-01-01

    Square-channel capillary, or 'Lobster-eye' arrays have been shown to be the optimum geometry for array optics. This configuration leads to a novel class of conditioning devices for X-ray and neutron beams. We present the first results of the focussing of neutrons with a Pb glass square-channel array. (authors)

  18. Diagnosis and incidence risk of clinical canine monocytic ehrlichiosis under field conditions in Southern Europe.

    Science.gov (United States)

    René-Martellet, Magalie; Lebert, Isabelle; Chêne, Jeanne; Massot, Raphaël; Leon, Marta; Leal, Ana; Badavelli, Stefania; Chalvet-Monfray, Karine; Ducrot, Christian; Abrial, David; Chabanne, Luc; Halos, Lénaïg

    2015-01-06

    Canine Monocytic Ehrlichiosis (CME), due to the bacterium Ehrlichia canis and transmitted by the brown dog tick Rhipicephalus sanguineus, is a major tick-borne disease in southern Europe. In this area, infections with other vector-borne pathogens (VBP) are also described and result in similar clinical expression. The aim of the present study was to evaluate the incidence risk of clinical CME in those endemic areas and to assess the potential involvement of other VBP in the occurrence of clinical and/or biological signs evocative of the disease. The study was conducted from April to November 2011 in veterinary clinics across Italy, Spain and Portugal. Sick animals were included when fitting at least three clinical and/or biological criteria compatible with ehrlichiosis. Serological tests (SNAP®4Dx, SNAP®Leish tests, Idexx, USA) and diagnostic PCR for E. canis, Anaplasma platys, Anaplasma phagocytophilum, Babesia spp, Hepatozoon canis and Leishmania infantum detection were performed to identify the etiological agents. Ehrlichiosis was considered when three clinical and/or biological suggestive signs were associated with at least one positive paraclinical test (serology or PCR). The annual incidence risk was calculated and data were geo-referenced for map construction. The probabilities of CME and other vector-borne diseases when facing clinical and/or biological signs suggestive of CME were then evaluated. A total of 366 dogs from 78 veterinary clinics were enrolled in the survey. Among them, 99 (27%) were confirmed CME cases, which allowed an estimation of the average annual incidence risk of CME amongst the investigated dog population to be 0.08%. Maps showed an increasing gradient of CME incidence risk from northern towards southern areas, in particular in Italy. It also suggested the existence of hot-spots of infections by VBP in Portugal. In addition, the detection of other VBP in the samples was common and the study demonstrated that a dog with clinical signs

  19. SU-E-T-403: Evaluation of the Beam Performance of a Varian TrueBeam Linear Accelerator Under External Device-Based Gated Delivery Conditions

    International Nuclear Information System (INIS)

    Kobulnicky, K; Pawlak, D; Purwar, A

    2015-01-01

    Purpose: To examine the beam performance of a Varian TrueBeam linear accelerator under external device-based gated delivery conditions. Methods: Six gating cycles were used to evaluate the gating performance of a standard production TrueBeam system that was not specially tuned in any way. The system was equipped with a factory installed external gating interface (EXGI). An in-house EXGI tester box was used to simulate the input gating signals. The gating cycles were selected based on long beam-on and short beam-off times, short beam-on and long beam-off times, or equal beam on and off times to check linac performance. The beam latencies were measured as the time difference between the logic high gating signal and the first or last target pulses with an oscilloscope. Tissue-Phantom Ratio, beam flatness, and dose distributions from 5 different plans were measured using the 6 different gating durations and the un-gated irradiation. A PTW 729 2-D array was used to compare 5 plans versus the un-gated delivery with a 1%/1mm gamma index passing criteria. Results: The beam latencies of the linac were based off of 20 samples for beam-on and beam-off, for each gating cycle. The average beam-on delays were measured to be between 57 and 66msec, with a maximum of 88 msec. The beam off latencies averaged between 19 and 26msec, with a maximum of 48 msec. TPR20,10 measurements showed beam energy stability within 0.5% of the un-gated delivery. Beam flatness was better than 2.5% for all gated cycles. All but two deliveries, the open field with 4 seconds on, 1 second off, and a five field IMRT plan with 0.5 seconds on, 2.5 seconds off, had >90% passing rate. Conclusion: TrueBeam demonstrates excellent beam stability with minimal beam latencies under external device-based gated operations. Dosimetric measurements show minimal variation in beam energy, flatness, and plan delivery. Authors are employees of Varian Medical Systems, Inc

  20. SU-E-T-403: Evaluation of the Beam Performance of a Varian TrueBeam Linear Accelerator Under External Device-Based Gated Delivery Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Kobulnicky, K; Pawlak, D; Purwar, A [Varian Medical Systems, Inc., Palo Alto, CA (United States)

    2015-06-15

    Purpose: To examine the beam performance of a Varian TrueBeam linear accelerator under external device-based gated delivery conditions. Methods: Six gating cycles were used to evaluate the gating performance of a standard production TrueBeam system that was not specially tuned in any way. The system was equipped with a factory installed external gating interface (EXGI). An in-house EXGI tester box was used to simulate the input gating signals. The gating cycles were selected based on long beam-on and short beam-off times, short beam-on and long beam-off times, or equal beam on and off times to check linac performance. The beam latencies were measured as the time difference between the logic high gating signal and the first or last target pulses with an oscilloscope. Tissue-Phantom Ratio, beam flatness, and dose distributions from 5 different plans were measured using the 6 different gating durations and the un-gated irradiation. A PTW 729 2-D array was used to compare 5 plans versus the un-gated delivery with a 1%/1mm gamma index passing criteria. Results: The beam latencies of the linac were based off of 20 samples for beam-on and beam-off, for each gating cycle. The average beam-on delays were measured to be between 57 and 66msec, with a maximum of 88 msec. The beam off latencies averaged between 19 and 26msec, with a maximum of 48 msec. TPR20,10 measurements showed beam energy stability within 0.5% of the un-gated delivery. Beam flatness was better than 2.5% for all gated cycles. All but two deliveries, the open field with 4 seconds on, 1 second off, and a five field IMRT plan with 0.5 seconds on, 2.5 seconds off, had >90% passing rate. Conclusion: TrueBeam demonstrates excellent beam stability with minimal beam latencies under external device-based gated operations. Dosimetric measurements show minimal variation in beam energy, flatness, and plan delivery. Authors are employees of Varian Medical Systems, Inc.

  1. Measurements of Pair Production Under Channelling Conditions by 70-180 GeV Photons Incident on Single Crystals

    CERN Multimedia

    2002-01-01

    This experiment will use the WA69 set-up to deliver a tagged photon beam in the energy range from 15~GeV to 150~GeV with a total angular spread of about @M~0.5~mrad. The incident photon direction is known to about 35~@mrad through the direction of the emitting electron. The photon beam is incident on an about 1~mm thick Ge single crystal in order to investigate pair production in single crystals. Above a certain energy threshold photons incident along crystal axis will show strongly increased pair production yi - the so-called .us Channelling Pair Production (ChPP). The produced pairs are analyzed in the @W-spectrometer. The large spread in incident photon angles offers an excellent opportunity to investigate in one single experiment the pair production in an angular region around a crystal axes and thereby compare ChPP with coherent (CPP) and incoherent (ICPP) processes. The very abrupt onset of ChPP (around threshold) will be measured and give a crucial test of the theoretical calculations. The differential...

  2. Constipation - prevalence and incidence among medical patients acutely admitted to hospital with a medical condition

    DEFF Research Database (Denmark)

    Noiesen, Eline; Trosborg, Ingelise; Bager, Louise

    2014-01-01

    To examine the prevalence and incidence of patient-reported symptoms of constipation in acutely hospitalised medical patients.......To examine the prevalence and incidence of patient-reported symptoms of constipation in acutely hospitalised medical patients....

  3. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, E. M.; James, H.; Bonora, M.; Yarnold, J. R.; Evans, P. M. [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Sutton SM2 5PT (United Kingdom); Physics Department, Ipswich Hospital NHS Foundation Trust, Ipswich IP4 5PD (United Kingdom); Department of Academic Radiotherapy, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton SM2 5PT, United Kingdom and School of Radiotherapy, University of Milan, Milan 20122 (Italy); Department of Academic Radiotherapy, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton SM2 5PT (United Kingdom); Centre for Vision Speech and Signal Processing, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2012-10-15

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that

  4. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    International Nuclear Information System (INIS)

    Donovan, E. M.; James, H.; Bonora, M.; Yarnold, J. R.; Evans, P. M.

    2012-01-01

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that

  5. Condition of the centers of linkage of serum albumin in cancer gynecological patients at beam therapy

    International Nuclear Information System (INIS)

    Malenchenko, A.F.; Belyakovskij, V.N.; Lukovskaya, N.D.; Prigozhaya, T.I.; Stasenkova, S.V.

    2009-01-01

    With the use of the method of fluorescent probes the condition of the centers of linkage of serum albumin in healthy women and in the cancer patients, passing a course of beam therapy, is analyzed at different modes. It is shown that general concentration of albumin in healthy persons and cancer patients are in the limits of normal values, however parameters of effective concentration of albumin, reserve of albumin linkage and toxicity index of patients statistically, for certain, differ in comparison with those in the control group. Carrying out the beam therapy course both split and not split promotes an increase of values of toxicity index. (authors)

  6. Measurements of the performance of a beam condition monitor prototype in a 5 GeV electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, M., E-mail: maria.hempel@desy.de [Brandenburg University of Technology Cottbus-Senftenberg, Cottbus 03013 (Germany); DESY, Zeuthen 15738 (Germany); Afanaciev, K. [NCPHEP, Minsk 220040 (Belarus); Burtowy, P.; Dabrowski, A. [CERN, Geneva 1211 (Switzerland); Henschel, H. [DESY, Zeuthen 15738 (Germany); Idzik, M. [AGH University of Science and Technology, Cracow 30-059 (Poland); Karacheban, O. [Brandenburg University of Technology Cottbus-Senftenberg, Cottbus 03013 (Germany); Lange, W.; Leonard, J. [DESY, Zeuthen 15738 (Germany); Levy, I. [Tel Aviv University, Tel Aviv 6997801 (Israel); Lohmann, W. [Brandenburg University of Technology Cottbus-Senftenberg, Cottbus 03013 (Germany); DESY, Zeuthen 15738 (Germany); Pollak, B. [Northwestern University, Evanston, IL 60208 (United States); Przyborowski, D. [AGH University of Science and Technology, Cracow 30-059 (Poland); Ryjov, V. [CERN, Geneva 1211 (Switzerland); Schuwalow, S. [DESY, Zeuthen 15738 (Germany); Stickland, D. [Princeton University, Princeton, NJ 08544 (United States); Walsh, R. [DESY, Zeuthen 15738 (Germany); Zagozdzinska, A. [CERN, Geneva 1211 (Switzerland)

    2016-08-01

    The Fast Beam Conditions Monitor, BCM1F, in the Compact Muon Solenoid, CMS, experiment was operated since 2008 and delivered invaluable information on the machine induced background in the inner part of the CMS detector supporting a safe operation of the inner tracker and high quality data. Due to the shortening of the time between two bunch crossings from 50 ns to 25 ns and higher expected luminosity at the Large Hadron Collider, LHC, in 2015, BCM1F needed an upgrade to higher bandwidth. In addition, BCM1F is used as an on-line luminometer operated independently of CMS. To match these requirements, the number of single crystal diamond sensors was enhanced from 8 to 24. Each sensor is subdivided into two pads, leading to 48 readout channels. Dedicated fast front-end ASICs were developed in 130 nm technology, and the back-end electronics is completely upgraded. An assembled prototype BCM1F detector comprising sensors, a fast front-end ASIC and optical analog readout was studied in a 5 GeV electron beam at the DESY-II accelerator. Results on the performance are given.

  7. Performance of New and Upgraded Detectors for Luminosity and Beam Condition Measurement at CMS

    CERN Document Server

    Leonard, Jessica Lynn

    2015-01-01

    The beam monitoring and luminosity systems of the CMS experiment are enhanced by several new and upgraded sub-detectors to match the challenges of the LHC operation and physics program at increased energy and higher luminosity. A dedicated pixelated luminosity telescope is installed for a fast and precise luminosity measurement. This detector measures coincidences between several three-layer telescopes of silicon pixel detectors to arrive at luminosity for each colliding LHC bunch pair. An upgraded fast beam conditions monitor measures the particle flux using single crystalline diamond sensors. It is equipped with a dedicated front-end ASIC produced in 130 nm CMOS technology. The excellent time resolution is used to separate collision products from machine induced background, thus serving as online luminosity measurement. A new beam-halo monitor at larger radius exploits Cerenkov light from fused silica to provide direction sensitivity and excellent time resolution to separate incoming and outgoing particles....

  8. Attractor of Beam Equation with Structural Damping under Nonlinear Boundary Conditions

    Directory of Open Access Journals (Sweden)

    Danxia Wang

    2015-01-01

    Full Text Available Simultaneously, considering the viscous effect of material, damping of medium, and rotational inertia, we study a kind of more general Kirchhoff-type extensible beam equation utt-uxxtt+uxxxx-σ(∫0l‍(ux2dxuxx-ϕ(∫0l‍(ux2dxuxxt=q(x, in  [0,L]×R+ with the structural damping and the rotational inertia term. Little attention is paid to the longtime behavior of the beam equation under nonlinear boundary conditions. In this paper, under nonlinear boundary conditions, we prove not only the existence and uniqueness of global solutions by prior estimates combined with some inequality skills, but also the existence of a global attractor by the existence of an absorbing set and asymptotic compactness of corresponding solution semigroup. In addition, the same results also can be proved under the other nonlinear boundary conditions.

  9. Analytical solution for beam with time-dependent boundary conditions versus response spectrum

    International Nuclear Information System (INIS)

    Gou, P.F.; Panahi, K.K.

    2001-01-01

    This paper studies the responses of a uniform simple beam for which the supports are subjected to time-dependent conditions. Analytical solution in terms of series was presented for two cases: (1) Two supports of a simple beam are subjected to a harmonic motion, and (2) One of the two supports is stationary while the other is subjected to a harmonic motion. The results of the analytical solution were investigated and compared with the results of conventional response spectrum method using the beam finite element model. One of the applications of the results presented in this paper can be used to assess the adequacy and accuracy of the engineering approaches such as response spectra methods. It has been found that, when the excitation frequency equals the fundamental frequency of the beam, the results from response spectrum method are in good agreement with the exact calculation. The effects of initial conditions on the responses are also examined. It seems that the non-zero initial velocity has pronounced effects on the displacement time histories but it has no effect on the maximum accelerations. (author)

  10. Efficacy of Thermally Conditioned Sisal FRP Composite on the Shear Characteristics of Reinforced Concrete Beams

    Directory of Open Access Journals (Sweden)

    Tara Sen

    2013-01-01

    Full Text Available The development of commercially viable composites based on natural resources for a wide range of applications is on the rise. Efforts include new methods of production and the utilization of natural reinforcements to make biodegradable composites with lignocellulosic fibers, for various engineering applications. In this work, thermal conditioning of woven sisal fibre was carried out, followed by the development of woven sisal fibre reinforced polymer composite system, and its tensile and flexural behaviour was characterized. It was observed that thermal conditioning improved the tensile strength and the flexural strength of the woven sisal fibre composites, which were observed to bear superior values than those in the untreated ones. Then, the efficacy of woven sisal fibre reinforced polymer composite for shear strengthening of reinforced concrete beams was evaluated using two types of techniques: full and strip wrapping techniques. Detailed analysis of the load deflection behaviour and fracture study of reinforced concrete beams strengthened with woven sisal under shearing load were carried out, and it was concluded that woven sisal FRP strengthened beams, underwent very ductile nature of failure, without any delamination or debonding of sisal FRP, and also increased the shear strength and the first crack load of the reinforced concrete beams.

  11. Molecular-beam epitaxy growth and structural characterization of semiconductor-ferromagnet heterostructures by grazing incidence X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Satapathy, D.K.

    2005-12-19

    The present work is devoted to the growth of the ferromagnetic metal MnAs on the semiconductor GaAs by molecular-beam epitaxy (MBE). The MnAs thin films are deposited on GaAs by molecular-beam epitaxy (MBE). Grazing incidence diffraction (GID) and reflection high-energy electron diffraction (RHEED) are used in situ to investigate the nucleation, evolution of strain, morphology and interfacial structure during the MBE growth. Four stages of the nucleation process during growth of MnAs on GaAs(001) are revealed by RHEED azimuthal scans. GID shows that further growth of MnAs films proceed via the formation of relaxed islands at a nominal thickness of 2.5 ML which increase in size and finally coalesce to form a continuous film. Early on, an ordered array of misfit dislocations forms at the interface releasing the misfit strain even before complete coalescence occurs. The fascinating complex nucleation process of MnAs on GaAs(0 0 1) contains elements of both Volmer-Weber and Stranski-Krastanov growth. A nonuniform strain amounting to 0.66%, along the [1 -1 0] direction and 0.54%, along the [1 1 0] direction is demonstrated from x-ray line profile analysis. A high correlation between the defects is found along the GaAs[1 1 0] direction. An extremely periodic array of misfit dislocations with a period of 4.95{+-}0.05 nm is formed at the interface along the [1 1 0] direction which releases the 7.5% of misfit. The inhomogeneous strain due to the periodic dislocations is confined at the interface within a layer of 1.6 nm thickness. The misfit along the [1 -1 0] direction is released by the formation of a coincidence site lattice. (orig.)

  12. The completeness condition and source orbits for exact image reconstruction in 3D cone-beam CT

    International Nuclear Information System (INIS)

    Mao Xiping; Kang Kejun

    1997-01-01

    The completeness condition for exact image reconstruction in 3D cone-beam CT are carefully analyzed in theory, and discussions about some source orbits which fulfill the completeness condition are followed

  13. Effect of storage conditions on graft of polypropylene non-woven fabric induced by electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jin Young; Jeun, Joon Pyo; Kang, Phil Hyun [Radiation Research Dvision for Industry and Environment, Korea Atomic Energy Research Institute, Jeongeup(Korea, Republic of)

    2015-05-15

    In this study, we fabricated effect of storage conditions on graft of polypropylene (PP) non-woven fabric induced by electron beam. The electron beam irradiations on PP non-woven fabric were carried out over a range of irradiation doses from 25 to 100 kGy to make free radicals on fabric surface. The radical measurement was established by electron spin resonance (ESR) for confirming the changes of the alkyl radical and peroxy radical according to effect of storage time, storage temperature and atmosphere. It was observed that the free radicals were increased with irradiation dose and decreased with storage time due to the continuous oxidation. However, the radical extinction was significantly delayed due to reduced mobility of radicals at extremely low temperature. The degree of graft based on the analysis of ESR was investigated. The conditions of graft reaction were set at a temperature: 60 degrees Celcius, reaction time: 6 hours and styrene monomer concentration: 20 wt%.

  14. Risk of Incidence of Hock Burn and Pododermatitis in Broilers Reared under Commercial Conditions

    Directory of Open Access Journals (Sweden)

    FG Jacob

    Full Text Available ABSTRACT The most common lesions observed in commercial broiler farms are hock burns and pododermatitis, defined as necrotic lesions on the plantar surface of the footpads and in the hock of growing broilers, causing pain and compromising broiler welfare. The present study aimed at identifying the risks of hock burns and pododermatitis in broilers reared under commercial conditions on new or reused litter. Twenty-four 40-d-old broilers reared in two houses in a commercial broiler farm. The plantar surface of the footpads and the hocks of broiler were recorded using infrared thermal images. The incidence of hock burns in broilers reared on new litter was 0.72 times lower than those on reused litter. Broilers reared on new litter presented lower risk (0.75, RR<1 of presenting pododermatitis when compared to those reared on reused litter. When simulating the risk using a larger sample, the simulated risk of broilers presenting footpad and hock lesions when reared on new litter was 38% higher those reared on reused litter.

  15. Quality of the Critical Incident Technique in practice: Interrater reliability and users' acceptance under real conditions

    Directory of Open Access Journals (Sweden)

    ANNA KOCH

    2009-03-01

    Full Text Available The Critical Incident Technique (CIT is a widely used task analysis method in personnel psychology. While studies on psychometric properties of the CIT so far primarily took into account relevance ratings of task-lists or attributes, and hence, only a smaller or adapted part of the CIT, little is known about the psychometric properties of the complete CIT in its most meaningful and fruitful way. Therefore, the aim of the present study was to assess interrater reliability and the participants’ view of the CIT under real conditions and especially to provide data for the key step of the CIT: the classification of behavior descriptions into requirements. Additionally, the cost-benefit-ratio and practicability were rated from the participants’ views as an important indicator for the acceptance of the task analysis approach in practice. Instructors of German Institutions for Statutory Accidents Insurance and Prevention as well as their supervisors took part in a job analysis with the CIT. Moderate interrater reliability for the relevance rating was found while the classification step yielded unexpectedly low coefficients for interrater reliability. The cost-benefit-ratio and practicability of the complete CIT were rated very positive. The results are discussed in relation to determinants that facilitate or impede the application of task analysis procedures.

  16. Performance of the Fast Beam Conditions Monitor BCM1F of CMS in the first running periods of LHC

    International Nuclear Information System (INIS)

    Schmidt, R S; Hempel, M; Lohmann, W; Bell, A J; Hall-Wilton, R; Mueller, S; Ryjov, V; Stickland, D; Castro, E; Lange, W; Walsh, R

    2011-01-01

    The Beam Conditions and Radiation Monitoring System, BRM, is implemented in CMS to protect the detector and provide an interface to the LHC. Seven sub-systems monitor beam conditions and the radiation level inside the detector on different time scales. They detect adverse beam conditions, facilitate beam tuning close to CMS, and measure the doses accumulated in different detector components. Data are taken and analysed independently of the CMS data acquisition, displayed in the control room, and provide inputs to the trigger system and the LHC operators. In case of beam conditions dangerous to the CMS detector, a beam abort is induced. The Fast Beam Conditions Monitor, BCM1F, is a flux counter close to the beam pipe inside the tracker volume. It uses single-crystal CVD diamond sensors, radiation-hard FE electronics, and optical signal transmission to measure the beam halo as well as collision products bunch by bunch. The system has been operational during the initiatory runs of LHC in September 2008. It works reliably since the restart in 2009 and is invaluable to CMS for everyday LHC operation. A characterisation of the system on the basis of data collected during LHC operation is presented.

  17. Performance of the fast beam conditions monitor BCM1F of CMS in the first running periods of LHC

    International Nuclear Information System (INIS)

    Schmidt, R.S.; Bell, A.J.; Castro, E.

    2010-12-01

    The Beam Conditions and Radiation Monitoring System, BRM, is implemented in CMS to protect the detector and provide an interface to the LHC. Seven sub-systems monitor beam conditions and the radiation level inside the detector on different time scales. They detect adverse beam conditions, facilitate beam tuning close to CMS, and measure the doses accumulated in different detector components. Data are taken and analysed independently of the CMS data acquisition, displayed in the control room, and provide inputs to the trigger system and the LHC operators. In case of beam conditions dangerous to the CMS detector, a beam abort is induced. The Fast Beam Conditions Monitor, BCM1F, is a flux counter close to the beam pipe inside the tracker volume. It uses single-crystal CVD diamond sensors, radiation-hard FE electronics, and optical signal transmission to measure the beam halo as well as collision products bunch by bunch. The system has been operational during the initiatory runs of LHC in September 2008. It works reliably since the restart in 2009 and is invaluable to CMS for everyday LHC operation. A characterisation of the system on the basis of data collected during LHC operation is presented. (orig.)

  18. Patient-reported safety incidents in older patients with long-term conditions: a large cross-sectional study.

    Science.gov (United States)

    Panagioti, Maria; Blakeman, Thomas; Hann, Mark; Bower, Peter

    2017-05-30

    Increasing evidence suggests that patient safety is a serious concern for older patients with long-term conditions. Despite this, there is a lack of research on safety incidents encountered by this patient group. In this study, we sought to examine patient reports of safety incidents and factors associated with reports of safety incidents in older patients with long-term conditions. The baseline cross-sectional data from a longitudinal cohort study were analysed. Older patients (n=3378 aged 65 years and over) with a long-term condition registered in general practices were included in the study. The main outcome was patient-reported safety incidents including availability and appropriateness of medical tests and prescription of wrong types or doses of medication. Binary univariate and multivariate logistic regression analyses were undertaken to examine factors associated with patient-reported safety incidents. Safety incidents were reported by 11% of the patients. Four factors were significantly associated with patient-reported safety incidents in multivariate analyses. The experience of multiple long-term conditions (OR=1.09, 95% CI 1.05 to 1.13), a probable diagnosis of depression (OR=1.36, 95% CI 1.06 to 1.74) and greater relational continuity of care (OR=1.28, 95% CI 1.08 to 1.52) were associated with increased odds for patient-reported safety incidents. Perceived greater support and involvement in self-management was associated with lower odds for patient-reported safety incidents (OR=0.95, 95% CI 0.93 to 0.97). We found that older patients with multimorbidity and depression are more likely to report experiences of patient safety incidents. Improving perceived support and involvement of patients in their care may help prevent patient-reported safety incidents. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Fragmentation and direct transfer reactions for 40Ar incident beam on 27Al target at 1760 MeV

    International Nuclear Information System (INIS)

    Cisse, Ousmane

    1985-01-01

    Peripheral collision studies performed with 40 Ar projectiles at 44 MeV/A and 27 Al target show that both fragmentation and transfer reactions can be discerned in this type of interaction. The experimental observation of fragments with masses charges and velocities close to those of the incident beam are the signature of transfer reactions and a detailed analysis of the energy spectra of such fragments has been carried out and interpreted in terms of a direct diffraction transfer model. On the other hand, for large mass transfer reactions, abrasion is the suitable mechanism. Inclusive fragment measurement together with the appropriate residual nuclei-fragment coincidence results then provides experimental data in good agreement with the theoretical predictions obtained from a participant spectator model. These investigations also indicate that the separation energies of the participant from the spectator nucleus, at least within the framework of the above model, can be interpreted in terms of a friction force which becomes more efficient as the projectile energy decreases. (author) [fr

  20. Health inequities: lower socio-economic conditions and higher incidences of intestinal parasites

    Directory of Open Access Journals (Sweden)

    Limoncu M Emin

    2007-11-01

    Full Text Available Abstract Background Intestinal parasitic infections affect child health and development and slow down growth, while reducing adults' productivity and work capacity. The aim of the present study was to determine and compare the incidences of intestinal parasitic infections and the socio-economic status of two near primary school children in Manisa, a western city of Turkey. Methods A total of 352 children were involved a questionnaire study from a private school (Ülkem Primary School – ÜPS, 116 children and a community-based school (Şehzadeler Primary School – ŞPS, 236 children. Of these, stool samples could be obtained from a total of 294 students; 97 (83.6% from ÜPS, and 197 (83.5% from ŞPS. The wet mount preparations of the stool samples were examined; samples were also fixed in polyvinyl alcohol and examined with modified formalin ethyl acetate sedimentation and trichrome staining techniques. Data were analyzed using SPSS for Windows version 10.0. The chi-squared test was used for the analytic assessment. Results The percentages of the students found to be infected with intestinal parasites, were 78 (39.6% and 13 (13.4% in ŞPS and ÜPS, respectively. Totally 91 (31.0% of the students from both schools were found to be infected with at least one intestinal parasite. Giardia lamblia was found to be the most common pathogenic intestinal parasite and Blastocystis hominis was prevalent independently from the hygienic conditions. The factors which significantly (p Conclusion Intestinal parasitic infections in school children were found to be a public health problem that increased due to lower socio-economic conditions. We conclude that organization of education seminars including the topics such as prevention of the infectious diseases, improving general hygienic conditions, and application of supportive programs for the parents may be suggested not only to reduce intestinal parasitic infections, but also to elevate the socio

  1. Increasing incidence of statin prescribing for the elderly without previous cardiovascular conditions:  A nation wide register study

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Andersen, Morten

    Supported by the growing evidence of the beneficial effects of statins in a range of conditions, statin utilization has increased considerably in most Western countries over the last decade. Objectives To estimate to what extent a widening of indication scope for statins accounts for the increasing...... Danish statin utilization during 1996-2005, applying treatment incidence as a measure of changing prescribing behaviour Methods From three nationwide registers, we retrieved individual records on demographics, dispensed prescription drugs and hospital discharges. Danish inhabitants were followed...... for seven cardiovascular conditions, corresponding to a hierarchy of statin indications. Poisson regression analyses were applied to quantify the incidence growth, according to age and indication.  Results Treatment incidence increased from 4/1000 person years in 2000 to 17/1000 in 2005, the increase being...

  2. Incidence of WHO stage 3 and 4 conditions following initiation of anti-retroviral therapy in resource limited settings.

    Directory of Open Access Journals (Sweden)

    Andrea J Curtis

    Full Text Available OBJECTIVES: To determine the incidence of WHO clinical stage 3 and 4 conditions during early anti-retroviral therapy (ART in resource limited settings (RLS. DESIGN/SETTING: A descriptive analysis of routine program data collected prospectively from 25 Médecins Sans Frontières supported HIV treatment programs in eight countries between 2002 and 2010. SUBJECTS/PARTICIPANTS: 35,349 study participants with median follow-up on ART of 1.33 years (IQR 0.51-2.41. OUTCOME MEASURES: Incidence in 100 person-years of WHO stage 3 or 4 conditions during 5 periods after ART initiation. Diagnoses of conditions were made according to WHO criteria and relied upon clinical assessments supported by basic laboratory investigations. RESULTS: The incidence of any WHO clinical stage 3 or 4 condition over 3 years was 40.02 per 100 person-years (31.77 for stage 3 and 8.25 for stage 4. The incidence of stage 3 and 4 conditions fell by over 97% between months 0-3 and months 25-36 (77.81 to 2.40 for stage 3 and 28.70 to 0.64 for stage 4. During months 0-3 pulmonary tuberculosis was the most common condition diagnosed in adults (incidence 22.24 per 100 person-years and children aged 5-14 years (25.76 and oral candidiasis was the most common in children <5 years (25.79. Overall incidences were higher in Africa compared with Asia (43.98 versus 12.97 for stage 3 and 8.98 versus 7.05 for stage 4 conditions, p<0.001. Pulmonary tuberculosis, weight loss, oral and oesophageal candidiasis, chronic diarrhoea, HIV wasting syndrome and severe bacterial infections were more common in Africa. Extra-pulmonary tuberculosis, non-tuberculous mycobacterial infection, cryptococcosis, penicilliosis and toxoplasmosis were more common in Asia. CONCLUSIONS: The incidence of WHO stage 3 and 4 conditions during the early period after ART initiation in RLS is high, but greatly reduces over time. This is likely due to both the benefits of ART and deaths of the sickest patients occurring shortly

  3. The Effect of the Implementation of the National Program for Hospital Preparedness on the Readiness of Nurses Under Simulated Conditions of Incidents and Disasters

    Directory of Open Access Journals (Sweden)

    Sedighe Yousefi

    2016-10-01

    Conclusion: The results of this study showed that education of national hospital preparedness program under simulated conditions of incidents and disasters increased knowledge, attitude, and performance (preparation of nurses in response to the incidents and disasters.

  4. Long range heliostat target using array of normal incidence pyranometers to evaluate a beam of solar radiation

    Science.gov (United States)

    Ghanbari, Cheryl M; Ho, Clifford K; Kolb, Gregory J

    2014-03-04

    Various technologies described herein pertain to evaluating a beam reflected by a heliostat. A portable target that has an array of sensors mounted thereupon is configured to capture the beam reflected by the heliostat. The sensors in the array output measured values indicative of a characteristic of the beam reflected by the heliostat. Moreover, a computing device can generate and output data corresponding to the beam reflected by the heliostat based on the measured values indicative of the characteristic of the beam received from the sensors in the array.

  5. Characteristics of thin film fullerene coatings formed under different deposition conditions by power ion beams

    International Nuclear Information System (INIS)

    Petrov, A.V.; Ryabchikov, A.I.; Struts, V.K.; Usov, Yu.P.; Renk, T.J.

    2007-01-01

    Carbon allotropic form - C 60 and C 70 can be used in microelectronics, superconductors, solar batteries, logic and memory devices to increase processing tool wear resistance, as magnetic nanocomposite materials for record and storage information, in biology, medicine and pharmacology. In many cases it is necessary to have a thin-film containing C 60 and C 70 fullerene carbon coatings. A possibility in principle of thin carbon films formation with nanocrystalline structure and high content ∼30-95% of C 60 and C 70 fullerene mixture using the method of graphite targets sputtering by a power ion beam has been shown. Formation of thin-film containing C 60 and C 70 fullerene carbon coatings were carried out by means of deposition of ablation plasma on silicon substrates. Ablation plasma was generated as result of interaction of high-power pulsed ion beams (HPPIB) with graphite targets of different densities. It has been demonstrated that formation of fullerenes, their amount and characteristics of thin-film coatings depend on the deposition conditions. The key parameter for such process is the deposition rate, which determines thin film formation conditions and, subsequently, its structure and mechanical properties. Nano-hardness, Young module, adhesion to mono-crystalline silicon substrate, friction coefficient, roughness surface of synthesized coatings at the different deposition conditions were measured. These characteristics are under influence of such main process parameters as energy density of HPPIB, which, in turn, determinates the density and temperature of ablation plasma and deposition speed, which is thickness of film deposited for one pulse of ion current. Nano-hardness and Young module meanings are higher at the increasing of power density of ion beam. Adhesion value is less at the high deposition speed. As rule, friction coefficient depends on vice versa from roughness. (authors)

  6. Sampling conditions of the three dimensional (3D) fan beam X ray transform

    International Nuclear Information System (INIS)

    Desbat, L.; Roux, S.; Grangeat, P.; Koenig, A.

    2003-01-01

    We give the sampling conditions of the 3 D fan beam X ray transform (3.D.F.B.X.R.T.). The motivation of this work lie in the fact that helical tomography with a single detector line is simply a sampling of this transform under the helical constraint. we give a precise description of the geometry of the essential support of Fourier transform of the 3.D.F.B.X.R.T. and we show how to derive efficient sampling. (N.C.)

  7. Finding Multiple Peaks Signal in Fast Beam Conditions Monitor (BCM1F)

    CERN Document Server

    Bin Ab Maalek, Abu Ubaidah Amir; CERN. Geneva. EP Department

    2017-01-01

    Fast Beam Conditions Monitor (BCM1F) is diamond and silicon sensors based luminometer of CMS detector. The methods of finding multiple peaks signal in BCM1F is shown. Multiple peaks signal found at signal with width between 60 ns - 300 ns. Double peaks are counted as single hit in the constant threshold analysis and leads to underestimation in the luminosity. Therefore it should be estimated for different filling schemes and sensor types. The percentage of long width pulse in different sensor for different fill are calculated. About 30 \\% long width pulse found in sCVD sensor, 12 \\% in pCVD and no more than 1 \\% for silicon sensor.

  8. Beam plug replacement and alignment under high radiation conditions for cold neutron facilities at Hanaro

    International Nuclear Information System (INIS)

    Yeong-Garp, Cho; Jin-Won, Shin; Jung-Hee, Lee; Jeong-Soo, Ryu

    2010-01-01

    Full text : The HANARO, an open-tank-in-pool type research reactor of a 30 MWth power in Korea, has been operating for 15 years since its initial criticality in February 1995. The beam port assigned for the cold neutron at HANARO had been used for an 8-m SANS without neutron guides until it was replaced by a cold neutron guide system in 2008. It was developed a cold neutron guide system for the delivery of cold neutrons from the cold neutron source in the reactor to the neutron scattering instruments in the guide hall. Since the HANARO has been operated from 1995, it was a big challenge to replace the existing plug and shutter with the new facilities under high radiation conditions. When the old plug was removed from the beam port in 2008, the radiation level was 230 mSv/hr at the end of beam port. In addition to that, there were more difficult situations such as the poor as-built dimensions of the beam port, limited work space and time constraint due to other constructions in parallel in the reactor hall. Before the removal of the old plug the level of the radiation was measured coming out through a small hole of the plug to estimate the radiation level during the removal of the old plug and installation of a new plug. Based on the measurement and analysis results, special tools and various shielding facilities were developed for the removal of old in-pile plug and the installation of the new in-pile plug assembly safely. In 2008, the old plug and shutter were successfully replaced by the new plug and shutter as shown in this article with a minimum exposure to the workers. A laser tracker system was also one of the main factors in our successful installation and alignment under high radiation conditions and limited work space. The laser tracker was used to measure and align all the mechanical facilities and the neutron guides with a minimum radiation exposure to workers. The alignment of all the guides and accessories were possible during reactor operation because

  9. Effect of pump-beam conditions on dual polarization oscillations in a microchip Nd:GdVO{sub 4} laser

    Energy Technology Data Exchange (ETDEWEB)

    Lin, C-C; Jiang, I-M [Department of Physics, National Sun Yat-Sen University, Kaohsiung 804, Taiwan (China); Ko, J-Y; Tsai, K-T; Cheng, Y-T; Ho, M-C, E-mail: jyko@nknucc.nknu.edu.t [Department of Physics, National Kaohsiung Normal University, Kaohsiung 824, Taiwan (China)

    2009-08-28

    This study investigated the input-output characteristics of a laser-diode-end-pumped microchip Nd:GdVO{sub 4} laser under different pump-beam focusing conditions by varying the magnifications of the microscope objective lenses and pump-beam positions on a chip. Dual-polarization oscillations were generated in the entire pump region using pumping conditions associated with different temperature gradients.

  10. Studies of the Influence of Beam Profile and Cooling Conditions on the Laser Deposition of a Directionally-Solidified Superalloy

    Directory of Open Access Journals (Sweden)

    Shuo Yang

    2018-02-01

    Full Text Available In the laser deposition of single crystal and directionally-solidified superalloys, it is desired to form laser deposits with high volume fractions of columnar grains by suppressing the columnar-to-equiaxed transition efficiently. In this paper, the influence of beam profile (circular and square shapes and cooling conditions (natural cooling and forced cooling on the geometric morphology and microstructure of deposits were experimentally studied in the laser deposition of a directionally-solidified superalloy, IC10, and the mechanisms of influence were revealed through a numerical simulation of the thermal processes during laser deposition. The results show that wider and thinner deposits were obtained with the square laser beam than those with the circular laser beam, regardless of whether natural or forced cooling conditions was used. The heights and contact angles of deposits were notably increased due to the reduced substrate temperatures by the application of forced cooling for both laser beam profiles. Under natural cooling conditions, columnar grains formed epitaxially at both the center and the edges of the deposits with the square laser beam, but only at the center of the deposits with the circular laser beam; under forced cooling conditions, columnar grains formed at both the center and the edges of deposits regardless of the laser beam profile. The high ratios of thermal gradient and solidification velocity in the height direction of the deposits were favorable to forming deposits with higher volume fractions of columnar grains.

  11. Codes of practice and protocols for the dosimetry in reference conditions of proton and ion beams

    International Nuclear Information System (INIS)

    Vatnitsky, S.; Andreo, P.

    2002-01-01

    The advantages of radiotherapy protons and heavier charged-particle beams, the technological feasibility, and the clinical results obtained so far have led to the establishment of about 20 treatment facilities worldwide and plans to open another 20 proton and light-ion therapy centres in the next five years. In order to meet the expanding capabilities of treatment techniques, considerable effort has been devoted during the last fifteen years to the development of the dosimetry and calibration of such beams. This paper reviews these developments and summarizes the present status of Codes of Practice and protocols for the dosimetry in reference conditions of proton and ion beams. The first dosimetry protocol for heavy-particle radiotherapy beams, AAPM TG 20, was based on the use of Faraday cups and calorimeters, whereas ionization chamber dosimetry received little attention. Following the trends in 'nuclear particle' radiotherapy, TG 20 included recommendations for specifying 'dose to tissue'. The lack of availability of a harmonized set of data for the different particles made this protocol to include data for stopping-powers and for the mean energy required to produce and ion pair in air, W air , from multiple authors, without enough attention being paid to their consistency. The increased focus into proton beams was materialized in the publication of the ECHED Code of Practice, dedicated exclusively to protons, where ionization dosimetry received more attention than in TG 20. It was not until the publication of the Supplement to the ECHED recommendations that ionization chambers having a 60 CO calibration factor were recommended as a reference detector for proton dosimetry, and data supplied for chambers with different wall materials. The emphasis on ionization chamber-based proton dosimetry was complemented with a recommendation for using water as dosimetry phantom material and the necessary data on tissue and water to air stopping-power ratios and W air . One of

  12. TLD Postal service for quality audits of beams of Co-60 in reference conditions in Cuba

    International Nuclear Information System (INIS)

    Gutierrez L, S.; Walwyn S, G.; Alonso V, G.

    2006-01-01

    Purpose: To describe the methodology and experience of the Secondary Laboratory of Dosimetric Calibration of Cuba in the establishment of the TLD Postal Service for quality audits of beams of Co-60 in reference conditions. Materials and methods: Through the Coordinated Project of Research (Contract 10794) its was bought 200 solid thermoluminescent detectors of LiF: Mg, Ti (TLD-100) in micro bars form with dimensions of 6 x 1 x 1 mm and of the JR 1152F type manufactured in China. All these detectors were identified individually with a serial number on one of its faces, using a graphite fine sheet. Those detectors for its irradiation are introduced in cylindrical plastic capsules developed and used by the International Atomic Energy Agency (IAEA) in the Audit Postal Service of Dose IAEA/WHO, the capsules have one cavity equal to 3 mm for that is necessary to recover this cavity with a fine plastic tube so that the detectors remain immobile during the irradiation. The method used to determine the individual sensitivity of the thermoluminescent detectors is: to irradiate a detectors group (100 micro bars) 4 times in those same geometric conditions, with the same irradiation history and reading, then it is determine for each detector a sensitivity factor equal to the average of those readings obtained for the 4 irradiation cycles for each i detector among the average of all the reading values obtained during the 4 cycles. The thermoluminescent signal is obtained with a Harshaw 2000C/B reader manual. Results: The satisfactory results obtained in the verification of the calibration of the TLD system, using the reference irradiation service of the Seibersdorf Dosimetry Laboratory of the IAEA in three different years are shown. The results of the audits carried out to the different radiotherapy services of the country in different years are also presented. Conclusions: The experience with the detectors acquired in the project demonstrates that with an appropriate

  13. On the energetics of a damped beam-like equation for different boundary conditions

    International Nuclear Information System (INIS)

    Sandilo, S.H.; Sheikh, A.H.; Soomro, A.R.

    2017-01-01

    In this paper, the energy estimates for a damped linear homogeneous beam-like equation will be considered. The energy estimates will be studied for different BCs (Boundary Conditions) for the axially moving continuum. The problem has physical and engineering application. The applications are mostly occurring in models of conveyor belts and band-saw blades. The research study is focused on the Dirichlet, the Neumann and the Robin type of BCs. From physical point of view, the considered mathematical model expounds the transversal vibrations of a moving belt system or moving band-saw blade. It is assumed that a viscous damping parameter and the horizontal velocity are positive and constant. It will be shown in this paper that change in geometry or the physics of the boundaries can affect the stability properties of the system in general and stability depends on the axial direction of the motion. In all cases of the BCs, it will be shown that there is energy decay due to viscous damping parameter and it will also be shown that in some cases there is no conclusion whether the beam energy decreases or increases. The detailed physical interpretation of all terms and expressions is provided and studied in detail. (author)

  14. On the Energetics of a Damped Beam-Like Equation for Different Boundary Conditions

    Directory of Open Access Journals (Sweden)

    SAJAD HUSSAIN SANDILO

    2017-04-01

    Full Text Available In this paper, the energy estimates for a damped linear homogeneous beam-like equation will be considered. The energy estimates will be studied for different BCs (Boundary Conditions for the axially moving continuum. The problem has physical and engineering application. The applications are mostly occurring in models of conveyor belts and band-saw blades. The research study is focused on the Dirichlet, the Neumann and the Robin type of BCs. From physical point of view, the considered mathematical model expounds the transversal vibrations of a moving belt system or moving band-saw blade. It is assumed that a viscous damping parameter and the horizontal velocity are positive and constant. It will be shown in this paper that change in geometry or the physics of the boundaries can affect the stability properties of the system in general and stability depends on the axial direction of the motion. In all cases of the BCs, it will be shown that there is energy decay due to viscous damping parameter and it will also be shown that in some cases there is no conclusion whether the beam energy decreases or increases. The detailed physical interpretation of all terms and expressions is provided and studied in detail.

  15. The CMS Fast Beams Condition Monitor Backend Electronics based on MicroTCA technology

    CERN Document Server

    Zagozdzinska, Agnieszka Anna

    2016-01-01

    The Fast Beams Condition Monitor (BCM1F), upgraded for LHC Run II, is one sub-system of the Beam Radiation Instrumentation and Luminosity Project of the CMS experiment. It is based on 24 single crystal CVD diamond sensors. Each sensor is metallised with two pads, being read out by a dedicated fast frontend chip produced in 130 nm CMOS technology. Signals for real time monitoring are processed by custom-made back-end electronics to measure separately rates corresponding to LHC collision products, machine induced background and residual activation exploiting different arrival times. The system is built in MicroTCA technology and uses high speed analog-to-digital converters. The data processing module designed for the FPGA allows a distinguishing of collision and machine induced background, both synchronous to the LHC clock, from the residual activation products. In operational modes of high rates, consecutive events, spaced in time by less than 12.5 ns, may partially overlap. Hence, novel signal processing tec...

  16. Designing of the Low Energy Beam Lines with Achromatic Condition in the RAON Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyunchang; Jang, Ji-Ho; Jeon, Dong-O [Institute for Basic Science, Daejeon (Korea, Republic of)

    2017-01-15

    The RAON accelerator has been built to create and accelerate stable heavy-ion beams and rare isotope beams. The stable heavy-ion beams are generated by the superconducting electron cyclotron resonance ion source and accelerated by the low energy superconducting linac SCL1. The beams accelerated by the SCL1 are re-accelerated by the high energy superconducting linac SCL2 for the generation of rare isotope beams by using the in-flight fragmentation system or are put to use in the low energy experimental halls, which include the neutron science facility and the Korea Broad acceptance Recoil spectrometer and Apparatus after having passed through the low energy beam lines which have long deflecting sections. At the end of each beam line in the low energy experimental halls, the beams should meet the targets of the two facilities with the specific requirements satisfied. Namely, if the beam is to be sent safely and accurately to the targets and simultaneously, satisfy the requirements, an achromatic lattice design needs to be applied in each beam line. In this paper, we will present the lattice design of the low energy beam lines and describe the results of the beam dynamics simulations. In addition, the correction of the beam orbit, which is distorted by machine imperfections, will be discussed.

  17. Architecture of the upgraded BCM1F Backend Electronics for Beam Conditions and Luminosity measurement - hardware and firmware

    CERN Document Server

    Zagozdzinska, Agnieszka Anna; Przyborowski, D.; Leonard, J.L.; Pozniak, K.T.; Miraglia, M.; Walsh, R.; Lange, W.; Lohmann, W.; Ryjov, V.

    2015-01-01

    The Beam Radiation Instrumentation and Luminosity Project of the CMS experiment, consists of several beam monitoring systems. One system, the upgraded Fast Beams Condition Monitor, is based on 24 single crystal CVD diamonds with a double-pad sensor metallization and a custom designed readout. Signals for real time monitoring are transmitted to the counting room, where they are received and processed by new back-end electronics designed to extract information on LHC collision, beam induced background and activation products. Data in the form of histograms is transmitted to the DAQ. The system architecture and the signal processing algorithms will be presented.SummaryThe Fast Beam Conditions Monitor (BCM1F) detector is a part of the CMS Beam Radiation Instrumentation and Luminosity Project (BRIL). The increased performance expected of the LHC with energy of up to 14 TeV, higher luminosity and 25 ns bunch spacing is a challenge for the detector systems and increase the importance of real-time beam monitoring at ...

  18. Testbeam results of the upgraded fast beam condition monitor at CMS

    Energy Technology Data Exchange (ETDEWEB)

    Hempel, Maria; Karacheban, Olena; Lohmann, Wolfgang [BTU, Cottbus (Germany); DESY, Zeuthen (Germany); Afanaciev, Konstantin [NCPHEP, Minsk (Belarus); Burtowy, Piotr; Ryjov, Vladimir; Zagozdzinska, Agnieszka [CERN, Geneva (Switzerland); Henschel, Hans; Lange, Wolfgang; Leonard, Jessica Lynn [DESY, Zeuthen (Germany); Levy, Itamar [Tel Aviv University, Tel Aviv (Israel); Przyborowski, Dominik [AGH-UST, Cracow (Poland); Schuwalow, Sergej; Walsh, Roberval [DESY, Hamburg (Germany)

    2016-07-01

    The Fast Beam Condition Monitor BCM1F at CMS is based on single-crystal diamond sensor with nanosecond time resolution. BCM1F delivered luminosity and machine induced background information to the CMS and LHC control room during the first running period of the LHC. A major upgrade to BCM1F was developed and built during the long shutdown of the LHC in 2014. The increased rate and the 25ns spacing should be handled with sensors subdivided by a double pad metallization and a faster new front-end ASIC. A prototype with these new components was investigated in the testbeam at DESY-II. The results are presented and also verified by Superfish simulations.

  19. Complete synchronization condition in a network of piezoelectric micro-beam

    International Nuclear Information System (INIS)

    Taffoti Yolong, V.Y.; Woafo, P.

    2007-10-01

    This work deals with the dynamics of a network of piezoelectric micro-beams. The complete synchronization condition for this class of chaotic nonlinear electromechanical systems devices with nearest-neighbor diffusive coupling is studied. The nonlinearities on the device studied here are both on the electrical component and on the mechanical one. The investigation is made for the case of a large number of discrete piezoelectric disks coupled. The problem of chaos synchronization is described and converted into the analysis of stability of the system via its differential equations. We show that the complete synchronization of N identical coupled nonlinear chaotic systems having the shift invariant coupling schemes can be calculated from the synchronization of two of them coupled in both directions. According to analytical, semi-analytical predictions and numerical calculations, the transition boundaries for chaos synchronization state in the coupled system are determined as a function of the increasing number of oscillators. (author)

  20. Optimal conditions for high current proton irradiations at the university of Wisconsin's ion beam laboratory

    International Nuclear Information System (INIS)

    Wetteland, C. J.; Field, K. G.; Gerczak, T. J.; Eiden, T. J.; Maier, B. R.; Albakri, O.; Sridharan, K.; Allen, T. R.

    2013-01-01

    The National Electrostatics Corporation's (NEC) Toroidal Volume Ion Source (TORVIS) source is known for exceptionally high proton currents with minimal service downtime as compared to traditional sputter sources. It has been possible to obtain over 150μA of proton current from the source, with over 70μA on the target stage. However, beam fluxes above ∼1×10 17 /m2-s may have many undesirable effects, especially for insulators. This may include high temperature gradients at the surface, sputtering, surface discharge, cracking or even disintegration of the sample. A series of experiments were conducted to examine the role of high current fluxes in a suite of ceramics and insulating materials. Results will show the optimal proton irradiation conditions and target mounting strategies needed to minimize unwanted macro-scale damage, while developing a procedure for conducting preliminary radiation experiments.

  1. Using condition and usefulness of dental cone-beam CT in endodontic treatment

    International Nuclear Information System (INIS)

    Kimura, Yuichi; Araki, Kazuyuki; Yamada, Yoshishige; Tagaya, Atsuko; Seki, Kenji; Okano, Tomohiro; Endo, Atsushi

    2009-01-01

    This study evaluated the condition and usefulness of the dental cone-beam CT (3DX) in clinical endodontic treatments. Images from 55 examinations of 49 patients obtained using 3DX during an 11-month period were evaluated retrospectively to identify the usefulness of this modality compared with periapical or panoramic radiographs. The main indication for using of 3DX was diagnosis of root fracture in 65% of the examinations, second was the presence and expansion of periapical lesion in 22%, and third was to detect the canal system or root abnormality in 13%. The 3DX visualizes bony anatomical structures precisely and detects the presence and expansion of periapical lesions and the canal system of each root of mulirooted teeth that cannot easily be observed by intraoral radiography or panoramic radiography. The results of this study suggest that 3DX is a useful and reliable tool for endodontic treatments. (author)

  2. A new luminometer and beam conditions monitor for the CMS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Karacheban, Olena; Hempel, Maria [Brandenburg University of Technology, Cottbus (Germany); DESY, Zeuthen (Germany); Dabrowski, Anne; Ryjov, Vladimir; Stickland, David; Zagozdzinska, Agnieszka [CERN, Geneva (Switzerland); Henschel, Hans; Lange, Wolfgang [DESY, Zeuthen (Germany); Leonard, Jessica; Walsh, Roberval [DESY, Hamburg (Germany); Levy, Itamar [Tel Aviv University, Tel Aviv (Israel); Lohmann, Wolfgang [Brandenburg University of Technology, Cottbus (Germany); RWTH Aachen University, Aachen (Germany); Przyborowski, Dominik [AGH-UST University, Cracow (Poland); Schuwalow, Sergej [DESY, Zeuthen (Germany); DESY, Hamburg (Germany)

    2016-07-01

    The luminosity is a key quantity of any collider, which allows for the determination of the absolute cross sections from the observed rate in a detector. The Fast Beam Conditions Monitor (BCM1F) was upgraded in the last LHC long technical stop (LS1) to 24 diamond sensors read out by a dedicated fast ASIC in 130 nm CMOS technology. The backend comprises a deadtime-less histogramming unit, with a 6.25 ns bin width, in VME standard. A microTCA system with better time resolution is in development. BCM1F is used for luminosity and machine induced background measurements at the CMS experiment. The performance of the detector in the first running period, as well as results on the calibration (Van-der-Meer scan) and the measurements of the luminosity are presented.

  3. TLD postal dose quality audit service for Co-60 beams in reference conditions in Cuba

    International Nuclear Information System (INIS)

    Gutierrez Lores, S.; Walwyn Salas, G.; Alonso Villanueva, G.

    2008-01-01

    This report presents the methodology and experience of the Cuban's Secondary Standard Dosimetry Laboratory for the implementation of postal dose quality audits service for Co-60 beams in reference conditions, using TLDs. Under coordinated research project (Contract 10794) were bought (TLD -100) Tl rods type JR 1152F made in China, with dimensions of 6 mm x 1 mm x 1 mm. All of these rods were identified individually with a consecutive number made over one of its sides, using a fine tip of graphite. The method used to determinate the individual sensibility of the TL detectors was: irradiating a group of them, with the same history of irradiation and readout (100 rods approximately), four serial times in the same geometrical conditions, to read them out and to attribute to each of them a sensitivity factor. This sensitivity factor is equal to average for the 4 cycle of irradiation and readout of the quote between the TL readout from dosimeter i and the mean of all values for each cycle. The TLD signal was read using HARSHAW 2000C/B reader. The results obtained in the external verification of the accuracy of the dose determination by the TLD system were performed in cooperation with IAEA Dosimetry Laboratory at Seibersdorf in different years are shown, the results obtained of the quality audits carried out to the different services of radiotherapy of the country are analysed also. The quality audits are an useful tool for the improvement of the accuracy in the dosimetry of clinical beams of radiotherapy with Co-60, contributing this way to the improvement of the life quality to cancer patients of the Cuban system of health. (author)

  4. Ultracompact and broadband polarization beam splitter based on polarization-dependent critical guiding condition.

    Science.gov (United States)

    Ying, Zhoufeng; Wang, Guanghui; Zhang, Xuping; Ho, Ho-pui; Huang, Ying

    2015-05-01

    An ultracompact and broadband polarization beam splitter (PBS) based on the polarization-dependent critical guiding condition of an asymmetrical directional coupler is proposed. The device consists of a pair of silicon waveguides with different height and width. Due to the different cutoff conditions for the TE and TM polarization modes, it is possible to have the TM mode guided in one waveguide while the TE mode is supported in both. Therefore, only the phase-matching condition for the cross-coupling of the TE mode needs to be considered. This approach not only simplifies the design procedures but also significantly improves device performance with smaller total length and larger bandwidth. Finally, regardless of the contribution of S-bend waveguides, our proposed PBS has a coupling region as short as 0.2 μm, which is the shortest reported until now. The simulation result shows that the extinction ratios for the TE and TM polarization are 13.5 and 16.6 dB at their respective output ports, and their insertion losses are 0.29 and 0.13 dB, respectively. Numerical simulations also show that the device offers a very large bandwidth (∼140  nm) with large extinction ratio (>10  dB) and low insertion loss (<1  dB).

  5. Incident report and estimates of personnel exposure for a staff present in maze corridor of linac room while radiation beam on

    International Nuclear Information System (INIS)

    Ravichandran, R.; Davis, C.A.; Ghamrawy, Kamal El; Arunkumar, L.S.

    2007-01-01

    The radiation safety features of high energy linear accelerator installations include primary and secondary barriers made of concrete (radiation bunkers), provision of maze wall for eliminating first scatter reaching the entrance door, locating room entrance perpendicular to maze corridor to reduce neutron dose. In addition, special motorized doors with lead lining and paraffin blocks, electrically interlocked to beam on-off system is provided for radiation safety. A radiation incident took place involving presence of a staff inside the Clinac 2300 CD room in September 2006 has been described

  6. Suitable exposure conditions for CB Throne? New model cone beam computed tomography unit for dental use

    International Nuclear Information System (INIS)

    Tanabe, Kouji; Nishikawa, Keiichi; Yajima, Aya; Mizuta, Shigeru; Sano, Tsukasa; Yajima, Yasutomo; Nakagawa, Kanichi; Kousuge, Yuuji

    2008-01-01

    The CB Throne is a cone beam computed tomography unit for dental use, and the smaller version of the CB MercuRay developed by Hitachi Medico Co. We investigated which exposure conditions were suitable in the clinical use. Suitable exposure conditions were determined by simple subjective comparisons. The right temporomandibular joint of the head phantom was scanned at all possible combinations of tube voltage (60, 80, 100, 120 kV) and tube current (10, 15 mA). Oblique-sagittal images of the same position were obtained using multiplanar reconstruction (MPR) function. Images obtained at 120 kV and 15 mA, which are the highest exposure conditions and certain to produce images of the best quality, were used to establish the standard. Eight oral radiologists observed each image and standard image on a LCD monitor. They compared subjectively spatial resolution and noise between each image and standard image using a 10 cm scale. Evaluation points were obtained from the check positions on the scales. The Steel method was used to determine significant differences. The images at 60 kV/10 mA and 80 kV/15 mA showed significantly lower evaluation points on spatial resolution. The images at 60 kV/10 mA, 60 kV/15 mA and 80 kV/10 mA showed significantly lower evaluation points on noise. In conclusion, even if exposure conditions are reduced to 100 kV/10 mA, 100 kV/15 mA or 120 kV/10 mA, the CB Throne will produce images of the best quality. (author)

  7. Studies of the Core Conditions of the Earth and Super-Earths Using Intense Ion Beams at FAIR

    Energy Technology Data Exchange (ETDEWEB)

    Tahir, N. A.; Neumayer, P.; Bagnoud, V. [GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, D-64291 Darmstadt (Germany); Lomonosov, I. V.; Shutov, A. [Institute of Problems of Chemical Physics, Russian Academy of Sciences, Institutskii pr. 18, 142432 Chernogolovka (Russian Federation); Borm, B. [Goethe-Universität Frankfurt, D-60438 Frankfurt (Germany); Piriz, A. R.; Piriz, S. A. [E.T.S.I. Industriales, Universidad de Castilla-La Mancha, E-13071 Ciudad Real (Spain)

    2017-09-01

    Using detailed numerical simulations, we present the design of an experiment that will generate samples of iron under extreme conditions of density and pressure believed to exist in the interior of the Earth and interior of extrasolar Earth-like planets. In the proposed experiment design, an intense uranium beam is used to implode a multilayered cylindrical target that consists of a thin Fe cylinder enclosed in a thick massive W shell. Such intense uranium beams will be available at the heavy-ion synchrotron, SIS100, at the Facility for Antiprotons and Ion Research (FAIR), at Darmstadt, which is under construction and will become operational in the next few years. It is expected that the beam intensity will increase gradually over a couple of years to its maximum design value. Therefore, in our studies, we have considered a wide range of beam parameters, from the initial beam intensity (“Day One”) to the maximum specified value. It is also worth noting that two different focal spot geometries have been used. In one case, a circular focal spot with a Gaussian transverse intensity distribution is considered, whereas in the other case, an annular focal spot is used. With these two beam geometries, one can access different parts of the Fe phase diagram. For example, heating the sample with a circular focal spot generates a hot liquid state, while an annular focal spot can produce a highly compressed liquid or a highly compressed solid phase depending on the beam intensity.

  8. Studies of the Core Conditions of the Earth and Super-Earths Using Intense Ion Beams at FAIR

    International Nuclear Information System (INIS)

    Tahir, N. A.; Neumayer, P.; Bagnoud, V.; Lomonosov, I. V.; Shutov, A.; Borm, B.; Piriz, A. R.; Piriz, S. A.

    2017-01-01

    Using detailed numerical simulations, we present the design of an experiment that will generate samples of iron under extreme conditions of density and pressure believed to exist in the interior of the Earth and interior of extrasolar Earth-like planets. In the proposed experiment design, an intense uranium beam is used to implode a multilayered cylindrical target that consists of a thin Fe cylinder enclosed in a thick massive W shell. Such intense uranium beams will be available at the heavy-ion synchrotron, SIS100, at the Facility for Antiprotons and Ion Research (FAIR), at Darmstadt, which is under construction and will become operational in the next few years. It is expected that the beam intensity will increase gradually over a couple of years to its maximum design value. Therefore, in our studies, we have considered a wide range of beam parameters, from the initial beam intensity (“Day One”) to the maximum specified value. It is also worth noting that two different focal spot geometries have been used. In one case, a circular focal spot with a Gaussian transverse intensity distribution is considered, whereas in the other case, an annular focal spot is used. With these two beam geometries, one can access different parts of the Fe phase diagram. For example, heating the sample with a circular focal spot generates a hot liquid state, while an annular focal spot can produce a highly compressed liquid or a highly compressed solid phase depending on the beam intensity.

  9. The Diffusion of Flexibility: Estimating the Incidence of Low-Regulated Working Conditions

    Directory of Open Access Journals (Sweden)

    Michael Allvin

    2013-09-01

    Full Text Available The purpose of this study is to determine the actual occurrences of flexible working conditions and to demonstrate an instrument for their assessment. Flexibility is discussed as a concept and defined in terms of deregulation of work, and a corresponding increase in self-government and ambiguity. Using empirical data from a national survey of the Swedish labor force, the results show that almost half (47% of the jobs on the Swedish labor market can be characterized as low, or even unregulated. This means that almost half of the Swedish work force is subjected to working conditions involving a nonnegligible requirement for self-government.

  10. Risk of Incidence of Hock Burn and Pododermatitis in Broilers Reared under Commercial Conditions

    OpenAIRE

    Jacob, FG; Baracho, MS; Nääs, IA; Lima, NSD; Salgado, DD; Souza, R

    2016-01-01

    ABSTRACT The most common lesions observed in commercial broiler farms are hock burns and pododermatitis, defined as necrotic lesions on the plantar surface of the footpads and in the hock of growing broilers, causing pain and compromising broiler welfare. The present study aimed at identifying the risks of hock burns and pododermatitis in broilers reared under commercial conditions on new or reused litter. Twenty-four 40-d-old broilers reared in two houses in a commercial broiler farm. The pl...

  11. Deployment Related Risk of Incident Mental Health Conditions Among Aeromedical Evacuation Crewmembers

    Science.gov (United States)

    2015-09-01

    everyday life, and decreasing the stigma associated with a diagnosis of a mental health condition. The Holmes-Rehe Stress Scale is commonly used to...being fatigued. A crucial factor to consider with this study is the stigma related to receiving a mental health diagnosis. While the Office of the...Alliance on Mental Illness estimates that up to 33% of qualified individuals are turned down for a job due to a psychiatric label (Williamson & Mulhall

  12. Electron beam effects on VLSI MOS conditions for testing and reconfiguration

    International Nuclear Information System (INIS)

    Girard, P.; Roche, F.M.; Pistoulet, B.

    1986-01-01

    Wafer scale integrated-MOS circuits problems related to test and reconfiguration by electron beams are analyzed. First of all the alterations in characteristics of MOS circuits submitted to an electron beam testing are considered. Then the capabilities of reconfiguration by an electron beam bombardment are discussed. The various phenomena involved are reviewed. Experimental data are reported and discussed on the light of data of the literature. (Auth.)

  13. Incidence of primary hypothyroidism in patients exposed to therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland

    Directory of Open Access Journals (Sweden)

    B A Laway

    2012-01-01

    Full Text Available Introduction: Hypothyroidism is a known consequence of external-beam radiotherapy to the neck encompassing a part or whole of the thyroid gland. In this non-randomized prospective study, we have tried to evaluate the response of the thyroid gland to radiation by assessing thyroid function before irradiation and at regular intervals after irradiation. Aims and Objectives: The aim of this study were to assess in the cancer patients, who were exposed to the therapeutic external beam radiation, where radiation portals include a part or whole of the thyroid gland: the incidence of primary hypothyroidism, the time required to become hypothyroid, any relation between the total dose for the development of hypothyroidism, and whether there are any patient or treatment-related factors that are predictive for the development of hypothyroidism, including the use of concurrent chemotherapy. Materials and Methods: This non-randomized, prospective study was conducted for a period of 2 years in which thyroid function was assessed in 59 patients (cases of head and neck cancer, breast cancer, lymphoma patients and other malignancies, who had received radiotherapy to the neck region. 59 euthyroid healthy patients (controls were also taken, who had not received the neck irradiation. These patients/controls were assessed periodically for 2 years. Results: The incidence of hypothyroidism after external beam radiation therapy (EBRT to neck where radiation portals include part or whole of the thyroid gland was 16.94%, seven cases had subclinical hypothyroidism (11.86% and three cases had clinical hypothyroidism (5.08%. Mean time for development of hypothyroidism was 4.5 months. There was no effect of age, gender, primary tumor site, radiation dose and chemotherapy, whether neoadjuvant or concurrent with the development of hypothyroidism. Conclusion: In summary, we found that thyroid dysfunction is a prevalent, yet easily treatable source of morbidity in patients

  14. Systems approach for condition management design: JET neutral beam system-A fusion case study

    Energy Technology Data Exchange (ETDEWEB)

    Khella, M., E-mail: M.Khella@lboro.ac.uk [Systems Engineering Innovation Centre (SEIC) - BAE Systems, Loughborough University, Holywell Park, Leicestershire LE11 3TU (United Kingdom); Pearson, J. [Systems Engineering Innovation Centre (SEIC) - BAE Systems, Loughborough University, Holywell Park, Leicestershire LE11 3TU (United Kingdom); Dixon, R. [Electronic and Electrical Engineering, Loughborough University, Leicestershire LE11 3TU (United Kingdom); Ciric, D.; Day, I.; King, R.; Milnes, J.; Stafford-Allen, R. [EURATOM/CCFE Fusion Association, Culham Science Centre, Oxfordshire OX14 3DB (United Kingdom)

    2011-10-15

    The maturation of any new technology can be coarsely divided into three stages of a development lifecycle: (1) fundamental research, (2) experimental rig development and testing through to (3) commercialization. With the enhancement of machines like JET, the building of ITER and the initiation of DEMO design activities, the fusion community is moving from stages 1 and 2 towards stage 3. One of the consequences of this transition will be a shift in emphasis from scientific achievement to maximizing machine reliability and availability. The fusion community should therefore be preparing itself for this shift by examining all methods and tools utilized in established engineering sectors that might help to improve these fundamental performance parameters. To this end, the Culham Centre for Fusion Energy (CCFE) has proactively engaged with UK industry to examine whether the development of condition management (CM) systems could help improve such performance parameters. This paper describes an initial CM design case study on the JET neutral beam system. The primary output of this study was the development of a CM design methodology that captures existing experience in fault detection, and classification as well as new methods for fault diagnosis. A summary of the methods used and the potential benefits of data fusion are presented here.

  15. Use of External Beam Radiotherapy Is Associated With Reduced Incidence of Second Primary Head and Neck Cancer: A SEER Database Analysis

    International Nuclear Information System (INIS)

    Rusthoven, Kyle; Chen Changhu; Raben, David; Kavanagh, Brian

    2008-01-01

    Purpose: Patients with head and neck cancer have a significant risk of developing a second primary cancer of the head and neck. We hypothesized that treatment with external beam radiotherapy (RT) might reduce this risk, because RT can eradicate occult foci of second head and neck cancer (HNCA). Methods and Materials: The data of patients with Surveillance, Epidemiology, and End Results Historic Stage A localized squamous cell carcinoma of the oral cavity, larynx, and pharynx were queried using the Surveillance, Epidemiology, and End Results database. For patients treated with or without RT, the incidence of second HNCA was determined and compared using the log-rank method. Cox proportional hazards analysis was performed for each site, evaluating the influence of covariates on the risk of second HNCA. Results: Between 1973 and 1997, 27,985 patients were entered with localized HNCA. Of these patients, 44% had received RT and 56% had not. The 15-year incidence of second HNCA was 7.7% with RT vs. 10.5% without RT (hazard ratio 0.71, p <0.0001). The effect of RT was more profound in patients diagnosed between 1988 and 1997 (hazard ratio 0.53, p <0.0001) and those with pharynx primaries (hazard ratio 0.47, p <0.0001). On multivariate analysis, RT was associated with a reduced risk of second HNCA for pharynx (p <0.0001) and larynx (p = 0.04) tumors. For oral cavity primaries, RT was associated with an increased risk of second HNCA in patients treated before 1988 (p <0.001), but had no influence on patients treated between 1988 and 1997 (p = 0.91). Conclusion: For localized HNCA, RT is associated with a reduced incidence of second HNCA. These observations are consistent with the eradication of microscopic foci of second HNCA with external beam RT

  16. Mechanical behaviour of vacuum chambers and beam screens under quench conditions in dipole and quadrupole fields

    CERN Document Server

    Rathjen, C

    2002-01-01

    A method based on analytical formulas is described to calculate bending moments, stresses, and deformations of vacuum chambers and beam screens in dipole and in quadrupole fields during a magnet quench. Solutions are given for circular and racetrack shaped structures. Without the need of time consuming calculations the solutions enable a quick design and verification of vacuum chambers and beam screens.

  17. Estimation methods of deformational behaviours of RC beams under the unrestrained condition at elevated temperatures

    International Nuclear Information System (INIS)

    Kanezu, Tsutomu; Nakano, Takehiro; Endo, Tatsumi

    1986-01-01

    The estimation methods of free deformations of reinforced concrete (RC) beams at elevated temperatures are investigated based on the concepts of ACI's and CEB/FIP's formulas, which are well used to estimate the flexural deformations of RC beams at normal temperature. Conclusions derived from the study are as follows. 1. Features of free deformations of RC beams. (i) The ratios of the average compressive strains on the top fiber of RC beams to the calculated ones at the cracked section show the inclinations that the ratios once drop after cracking and then remain constant according to temperature rises. (ii) Average compressive strains might be estimated by the average of the calculated strains at the perfect bond section and the cracked section of RC beam. (iii) The ratios of the average tensile strains on the level of reinforcements to the calculated ones at the cracked section are inclined to approach the value of 1.0 monotonically according to temperature rises. The changes of the average tensile strains are caused by the deterioration of bond strength and cracking due to the increase of the differences of expansive strains between reinforcement and concrete. 2. Estimation methods of free deformations of RC beams. (i) In order to estimate the free deformations of RC beams at elevated temperatures, the basic concepts of ACI's and CEB/FIP's formulas are adopted, which are well used to estimate the M-φ relations of RC beams at normal temperature. (ii) It was confirmed that the suggested formulas are able to estimate the free deformations of RC beams, that is, the longitudinal deformation and the curvature, at elevated temperatures. (author)

  18. Incidence of 'Candidatus Liberibacter asiaticus'-Infected Plants Among Citrandarins as Rootstock and Scion Under Field Conditions.

    Science.gov (United States)

    Boava, Leonardo Pires; Sagawa, Cíntia Helena Duarte; Cristofani-Yaly, Mariângela; Machado, Marcos Antonio

    2015-04-01

    Huanglongbing (HLB), caused by the bacterium 'Candidatus Liberibacter' spp., is currently one of the most serious diseases of citrus plants and has caused substantial economic losses. Thus far, there is no source of genetic resistance to HLB in the genus Citrus or its relatives. However, several studies have reported Poncirus trifoliata and some of its hybrids to be more tolerant to the disease. The main objective of this study was to report differences in the incidence of 'Ca. L. asiaticus' infection in citrandarin plants, hybrids from Sunki mandarin (Citrus sunki (Hayata) hort. ex Tanaka), and trifoliate orange Rubidoux (P. trifoliata (L.) Raf.)), after conducting an extensive survey under field conditions. These hybrid plants were established for approximately 7 years in an area with a high incidence of 'Ca. L. asiaticus'-infected plants. We selected two experimental areas (area A and area B), located approximately 10 m apart. Area A consists of Pera sweet orange (C. sinensis (L.) Osb.) grafted onto 56 different citrandarin rootstocks. Area B consists of citrandarin scions grafted onto Rangpur lime (C. limonia Osb.) rootstock. Bacteria in the leaves and roots were detected using real-time quantitative polymerase chain reaction. The incidence of 'Ca. L. asiaticus'-infected plants was 92% in area A and 14% in area B. Because infected plants occurred in both areas, we examined whether the P. trifoliata hybrid rootstock influenced HLB development and also determined the distribution of 'Ca. L. asiaticus' in Citrus tree tissues. Although this survey does not present evidence regarding the resistance of P. trifoliata and its hybrids in relation to bacteria or psyllids, future investigation, mainly using the most promising hybrids for response to 'Ca. L. asiaticus', will help us to understand the probable mechanism of defense or identifying compounds in P. trifoliata and its hybrids that are very important as strategy to combat HLB. Details of these results are

  19. Versatile 0.5 TW electron beam facility for power conditioning studies of large rare-gas/halide lasers

    International Nuclear Information System (INIS)

    Ramirez, J.J.

    1980-01-01

    Rare-gas/halide lasers which are being developed for Inertial Confinement Fusion will require large area, low impedance electron beam drivers. A wide range of electron beam parameters are being considered for future systems in an effort to optimize the overall system design. A number of power conditioning issues must be investigated in order to obtain a better understanding of the various trade-offs involved in making such optimizations. The RAYITO electron beam accelerator is being designed and built at Sandia National Laboratories and will be used for such investigations. It will be capable of operating in either a 2 or 4 ohm configuration at 1 MV, 50 ns or 0.8 MV, 200 ns. Design details for RAYITO are presented in this paper. Experiments planned for this facility are also discussed

  20. STRUCTURAL ANALYSIS OF RAILWAYS BOLSTER-BEAM UNDER COMMERCIAL OPERATION CONDITIONS: OVER-TRACTION AND OVER-BRAKING

    Directory of Open Access Journals (Sweden)

    Ronald M. MARTINOD

    2016-06-01

    Full Text Available The conditions for the operation of railway systems are closely related to the increase of the commercial demand; as a consequence, the performance of the structural elements of railways changes. The present paper focuses on a study of the structural behaviour of bolster-beams under commercial operation conditions of railway systems, specifically in the dynamic conditions generated in events of over-traction and over-braking on the vehicle running. The proposed work is constructed based on the following phases: (i analysis of the kinematics of the vehicle; (ii development of numerical models, a model based on the multibody theory, and a Finite Elements model; (iii development of experimental field tests; and (iv development of simulations for a detailed analysis of the structural behaviour for a study of the strain distribution in the main bolster-beam. This study is applied to a particular case of a railway system that provides commercial service to passengers.

  1. A phase II study of V-BEAM as conditioning regimen before second auto-SCT for multiple myeloma.

    Science.gov (United States)

    Wang, T-F; Fiala, M A; Cashen, A F; Uy, G L; Abboud, C N; Fletcher, T; Wu, N; Westervelt, P; DiPersio, J F; Stockerl-Goldstein, K E; Vij, R

    2014-11-01

    High-dose melphalan has been the standard conditioning regimen for auto-SCT in multiple myeloma (MM) for decades. A more effective conditioning regimen may induce deeper responses and longer remission duration. It is especially needed in the setting of second auto-SCT, which rarely achieves comparable results with the first auto-SCT using the same conditioning regimen. Here we conducted a phase II study to investigate the efficacy and safety of a conditioning regimen V-BEAM (bortezomib-BEAM) before second auto-SCT for multiple myeloma. Ten patients were enrolled from September 2012 to May 2013. The CR rate at day +100 after auto-SCT was 75%; all except for one patient remained in remission after a median follow-up of 6 months. Three patients developed Clostridium difficile infection. Two patients died within the first 30 days of auto-SCT from neutropenic colitis and overwhelming sepsis, respectively. Due to the high rate of morbidity and mortality, the study was terminated after 10 patients. In summary, although the conditioning regimen V-BEAM before second auto-SCT for MM provided promising responses, it was associated with unexpected treatment-related toxicity and should not be investigated further without modifications.

  2. Screening conditions in a magnetized plasma with electron beam, with application to ripple trapped electron losses

    Energy Technology Data Exchange (ETDEWEB)

    Faudot, E.; Heuraux, S. [Nancy-1 Univ. Henri Poincare, LPMIA, UMR CNRS 7040, 54 (France); Colas, L.; Saint-Laurent, F.; Martin, G.; Basiuk, V. [Association Euratom-CEA Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee

    2004-07-01

    In Tore Supra, electrons are accelerated by lower hybrid waves in the direction parallel to the confinement magnetic field, in order to drive non-inductive current. But electrons have also on increase of their perpendicular velocity, then 10% of the most energetic electrons get trapped in the magnetic ripple between 2 adjacent toroidal coils, thus forming a beam. The electron beam follows a banana trajectory, the 20 mm wide protection represented by a cooled copper tube is assumed to protect the VP entrance from this energetic flux. Nevertheless, this beam is able to go beyond the copper tube and creates a hot spot on the steel panel edge able to melt the metal. Heat fluxes deposition on the vertical port (VP) can be understood with a beam+sheath theory including the fact that the sheaths can be obstructed when their length becomes greater than flux tube length. By this way, we identify 4 deposition regimes: 2 free sheath regimes and 2 obstructed sheath regimes. Beam flux deposits either at the entrance of the VP along first 2 cm behind the copper tube or until the end of the VP when beam flux is high and for free sheath. Obstructed sheaths make the repulsive, potential for electrons decrease and so accelerate the flux deposition. (authors)

  3. Clinical management of the induction of labor in intrauterine fetal death: evaluation of incidence of cesarean section and related conditions

    Directory of Open Access Journals (Sweden)

    Maria Isabel do Nascimento

    2014-03-01

    Full Text Available OBJECTIVE: To assess the incidence and conditions associated with cesarean section in a cohort of pregnant women with intrauterine fetal death (IUFD, and clinical management to anticipate the childbirth. METHODS: It was a retrospective cohort study with 163 mothers with IUFD, at the second half of pregnancy, who were managed to anticipate childbirth using pharmacological preparations and/or a mechanical method (Foley catheter in a teaching hospital in Rio de Janeiro State, Brazil. Cox regression was used to evaluate the effect of the clinical methods on the kind of delivery. RESULTS: The Subgroups A (misoprostol or Oxytocin, B (misoprostol and Oxytocin, and C (Foley catheter alone or combined with misoprostol and/or Oxytocin were formed according to the applied methods. Nine out of 163 cases ended with cesarean section. The incidence of cesarean section was 3.5 per 1,000 people-hours, meaning that a pregnant woman with IUFD had a 15.6% risk of cesarean section during the first 48 hours of clinical management to anticipate childbirth. The conditions significantly associated with the mode of delivery were placental abruption (HR: 44.97, having two or more previous cesarean deliveries (HR: 10.03, and mechanical method with Foley catheter (HR: 5.01. CONCLUSION: Cesarean section was an essential conduct in this cohort and followed previous cesarean delivery and placental abruption. The effect of the mechanical method on the abdominal route suggests that the Foley catheter method was used in the most difficult cases and that the surgery was performed to ensure maternal health.

  4. Effective energies and exposure determinations of two different energy X-ray beams incident on a personnel monitor

    International Nuclear Information System (INIS)

    Okuno, E.; Cruz, M.T. da

    1984-01-01

    The effective energy of one X or gamma ray beam can be determined by means of two thermoluminescent (TL) dosemeters mounted between suitable filters. However, it has been observed that personnel monitors exposed to two different energy ionizing radiations provide different effective energies depeding on the type of TL phosphor used. This fact could be a powerful tool for identifying exposures to radiation with quite different effective energies which are very common in practice. Two types of TL dosemeters were used : pellets of cold pressed natural fluoride and NaCl developed in our own laboratory, and LiF, TLD-100 from Harshaw Chemical Co.. Experimental results obtained with these combined dosemeters after irradiation with different sets of exposures and energy values of ionizing radiations are also presented. (Author) [pt

  5. Link State Relationships Under Incident Conditions: Using a CTM-Based Linear Programming Dynamic Traffic Assignment Model

    Science.gov (United States)

    2010-03-01

    Urban transportation networks, consisting of numerous links and nodes, experience traffic incidents such as accidents and road maintenance work. A typical consequence of incidents is congestion which results in long queues and causes high travel time...

  6. Link state relationships under incident conditions : using a CTM-based linear programming dynamic traffic assignment model.

    Science.gov (United States)

    2010-03-01

    Urban transportation networks, consisting of numerous links and nodes, experience traffic incidents such as accidents and road : maintenance work. A typical consequence of incidents is congestion which results in long queues and causes high travel ti...

  7. Instantaneous axial force of a high-order Bessel vortex beam of acoustic waves incident upon a rigid movable sphere.

    Science.gov (United States)

    Mitri, F G; Fellah, Z E A

    2011-08-01

    The present investigation examines the instantaneous force resulting from the interaction of an acoustical high-order Bessel vortex beam (HOBVB) with a rigid sphere. The rigid sphere case is important in fluid dynamics applications because it perfectly simulates the interaction of instantaneous sound waves in a reduced gravity environment with a levitated spherical liquid soft drop in air. Here, a closed-form solution for the instantaneous force involving the total pressure field as well as the Bessel beam parameters is obtained for the case of progressive, stationary and quasi-stationary waves. Instantaneous force examples for progressive waves are computed for both a fixed and a movable rigid sphere. The results show how the instantaneous force per unit cross-sectional surface and unit pressure varies versus the dimensionless frequency ka (k is the wave number in the fluid medium and a is the sphere's radius), the half-cone angle β and the order m of the HOBVB. It is demonstrated here that the instantaneous force is determined only for (m,n) = (0,1) (where n is the partial-wave number), and vanishes for m>0 because of symmetry. In addition, the instantaneous force and normalized amplitude velocity results are computed and compared with those of a rigid immovable (fixed) sphere. It is shown that they differ significantly for ka values below 5. The proposed analysis may be of interest in the analysis of instantaneous forces on spherical particles for particle manipulation, filtering, trapping and drug delivery. The presented solutions may also serve as a method for comparison to other solutions obtained by strictly numerical or asymptotic approaches. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Extension of geometrical-optics approximation to on-axis Gaussian beam scattering. II. By a spheroidal particle with end-on incidence.

    Science.gov (United States)

    Xu, Feng; Ren, Kuan Fang; Cai, Xiaoshu; Shen, Jianqi

    2006-07-10

    On the basis of our previous work on the extension of the geometrical-optics approximation to Gaussian beam scattering by a spherical particle, we present a further extension of the method to the scattering of a transparent or absorbing spheroidal particle with the same symmetric axis as the incident beam. As was done for the spherical particle, the phase shifts of the emerging rays due to focal lines, optical path, and total reflection are carefully considered. The angular position of the geometric rainbow of primary order is theoretically predicted. Compared with our results, the Möbius prediction of the rainbow angle has a discrepancy of less than 0.5 degrees for a spheroidal droplet of aspect radio kappa within 0.95 and 1.05 and less than 2 degrees for kappa within 0.89 and 1.11. The flux ratio index F, which qualitatively indicates the effect of a surface wave, is also studied and found to be dependent on the size, refractive index, and surface curvature of the particle.

  9. Strength and behavior in shear of reinforced concrete deep beams under dynamic loading conditions

    Energy Technology Data Exchange (ETDEWEB)

    Adhikary, Satadru Das [School of Civil and Environmental Engineering, Nanyang Technological University, 639798 (Singapore); Li, Bing, E-mail: cbli@ntu.edu.sg [School of Civil and Environmental Engineering, Nanyang Technological University, 639798 (Singapore); Fujikake, Kazunori [Department of Civil and Environmental Engineering, National Defense Academy, Yokosuka 239 8686 (Japan)

    2013-06-15

    Highlights: ► Effects of wider range of loading rates on dynamic shear behavior of RC deep beams. ► Experimental investigation of RC deep beam with and without shear reinforcements. ► Verification of experimental results with truss model and FE simulation results. ► Empirical equations are proposed to predict the dynamic increase factor of maximum resistance. -- Abstract: Research on reinforced concrete (RC) deep beams has seen considerable headway over the past three decades; however, information on the dynamic shear strength and behavior of RC deep beams under varying rates of loads remains limited. This paper describes the experimental results of 24 RC deep beams with and without shear reinforcements under varying rates of concentrated loading. Results obtained serve as useful data on shear resistance, failure patterns and strain rates corresponding to varying loading rates. An analytical truss model approach proves its efficacy in predicting the dynamic shear resistance under varying loading rates. Furthermore, three-dimensional nonlinear finite element (FE) model is described and the simulation results are verified with the experimental results. A parametric study is then conducted to investigate the influence of longitudinal reinforcement ratio, transverse reinforcement ratio and shear span to effective depth ratio on shear behavior. Subsequently, two empirical equations were proposed by integrating the various parameters to assess the dynamic increase factor (DIF) of maximum resistance under varying rates of concentrated loading.

  10. Heavy-ion induced desorption of a TiZrV coated vacuum chamber bombarded with 5 MeV/u Ar8+ beam at grazing incidence

    International Nuclear Information System (INIS)

    Hedlund, E.; Malyshev, O. B.; Westerberg, L.; Krasnov, A.; Semenov, A. S.; Leandersson, M.; Zajec, B.; Kollmus, H.; Bellachioma, M. C.; Bender, M.; Kraemer, A.; Reich-Sprenger, H.

    2009-01-01

    TiZrV nonevaporable getter (NEG) coated vacuum chambers is a new vacuum technology which is already used in many particle accelerators worldwide. This coating is also of interest for heavy-ion accelerator vacuum chambers. Heavy-ion desorption yields from an activated as well as a CO saturated NEG coated tube have been measured with 5 MeV/u Ar 8+ beam. The sticking probability of the NEG film was obtained by using the partial pressure ratios on two sides of the NEG coated tube. These ratios were compared to results of modeling of the experimental setup with test particle Monte Carlo and angular coefficient methods. The partial pressures inside the saturated NEG coated tube bombarded with heavy ions were up to 20 times larger than those inside the activated one. However, the partial pressure of methane remained the same. The value of the total desorption yield from the activated NEG coated tube is 2600 molecules/ion. The desorption yields after saturation for CH 4 , H 2 , and CO 2 were found to be very close to the yields measured after the activation, while CO increased by up to a factor of 5. The total desorption yield for the saturated tube is up to 7000 molecules/ion. The large value of the desorption yield of the activated NEG coated tube, an order of magnitude higher than the desorption yield from a stainless steel tube at normal incident angle, could be explained by the grazing incident angle

  11. Voltage conditioning and beam performance of the 2OUR Pelletron at JAERI

    International Nuclear Information System (INIS)

    Norton, G.A.; Sundquist, M.L.; Daniel, R.E.; Rathmell, R.D.

    1982-01-01

    The Pelletron Model 2OUR was formally accepted by the Japan Atomic Energy Research Institute in Tokai, Japan, on August 10, 1982. The 2OUR is a 20 MV, folded tandem with a 300 kV injector with four ion sources on the injector deck. The 2OUR is equipped with an internal ion source and nanosecond bunching and pulsing system in the high voltage terminal. This ion source and pulsing system is designed to produce intense peak currents of proton and deuteron beams. The accelerator is also equipped with an external nanosecond bunching and pulsing system for nanosecond pulsed beams in the tandem mode for ions up to mass 240. The formal acceptance of the accelerator was based on operation at 18 MV. However, the 2OUR has operated in a very stable fashion, accelerating an oxygen beam with a terminal potential of 18.5 MV. Mechanical deficiencies outside of the accelerating tube presently limit operation below 20 MV

  12. Measurements of lateral penumbra for uniform scanning proton beams under various beam delivery conditions and comparison to the XiO treatment planning system

    International Nuclear Information System (INIS)

    Rana, Suresh; Zeidan, Omar; Ramirez, Eric; Rains, Michael; Gao, Junfang; Zheng, Yuanshui

    2013-01-01

    Purpose: The main purposes of this study were to (1) investigate the dependency of lateral penumbra (80%–20% distance) of uniform scanning proton beams on various factors such as air gap, proton range, modulation width, compensator thickness, and depth, and (2) compare the lateral penumbra calculated by a treatment planning system (TPS) with measurements.Methods: First, lateral penumbra was measured using solid–water phantom and radiographic films for (a) air gap, ranged from 0 to 35 cm, (b) proton range, ranged from 8 to 30 cm, (c) modulation, ranged from 2 to 10 cm, (d) compensator thickness, ranged from 0 to 20 cm, and (e) depth, ranged from 7 to 15 cm. Second, dose calculations were computed in a virtual water phantom using the XiO TPS with pencil beam algorithm for identical beam conditions and geometrical configurations that were used for the measurements. The calculated lateral penumbra was then compared with the measured one for both the horizontal and vertical scanning magnets of our uniform scanning proton beam delivery system.Results: The results in the current study showed that the lateral penumbra of horizontal scanning magnet was larger (up to 1.4 mm for measurement and up to 1.0 mm for TPS) compared to that of vertical scanning magnet. Both the TPS and measurements showed an almost linear increase in lateral penumbra with increasing air gap as it produced the greatest effect on lateral penumbra. Lateral penumbra was dependent on the depth and proton range. Specifically, the width of lateral penumbra was found to be always lower at shallower depth than at deeper depth within the spread out Bragg peak (SOBP) region. The lateral penumbra results were less sensitive to the variation in the thickness of compensator, whereas lateral penumbra was independent of modulation. Overall, the comparison between the results of TPS with that of measurements indicates a good agreement for lateral penumbra, with TPS predicting higher values compared to

  13. Possibilities and conditions of applying PIXE analysis with external proton beam

    International Nuclear Information System (INIS)

    Potocek, V.

    1989-01-01

    The technical and methodological prerequisites are summed up for the use of the PIXE method with an external proton beam. The method is suitable for the preliminary analysis of unknown samples prior to the choice of the best suited analytical method, for the nondestructive analysis of rare samples such as unique works of art, of small amounts of materials which are difficult to access, etc., as well as for calibration and comparing analyses. As for the operators the application of the PIXE method with external proton beam assumes the availability of accelerator operating time, minimization of the length of exposure of the targets, optimization of parameters of the exciting beam and automation of the whole process. Attention is also devoted to technical provisions and organization of laboratory work. The design is described of an analytical unit using the PIXE method with external proton beam, and it is stated that the Van de Graaff accelerator at the Institute of Nuclear Physics in Rez near Prague could be used for the purpose. (Z.M.). 6 refs

  14. Rhizophagus irregularis MUCL 41833 transitorily reduces tomato bacterial wilt incidence caused by Ralstonia solanacearum under in vitro conditions.

    Science.gov (United States)

    Chave, Marie; Crozilhac, Patrice; Deberdt, Péninna; Plouznikoff, Katia; Declerck, Stéphane

    2017-10-01

    Bacterial wilt caused by Ralstonia solanacearum is one of the world's most important soil-borne plant diseases. In Martinique, French West Indies, a highly virulent new pathogenic variant of this bacterium (phylotype IIB/4NPB) severely impacts tomato production. Here we report on the effect of R. solanacearum CFBP 6783, classified in phytotype IIB/4NPB, on tomato plantlets grown under strict in vitro culture conditions in the presence or absence of the arbuscular mycorrhizal fungus Rhizophagus irregularis MUCL 41833. A mycelium donor plant (i.e. Crotalaria spectabilis) was used for rapid, uniform mycorrhization of tomato plantlets that were subsequently infected by the bacterium. Bacterial wilt was significantly delayed and the incidence of the disease consequently reduced in the mycorrhizal tomato plantlets. Conversely, R. solanacearum did not affect root colonization by the AMF within the 16 days of the experiment. These results suggested that the mycorrhizal fungus was able to reduce bacterial wilt symptoms, probably by eliciting defence mechanisms in the plant.

  15. Neutron-induced damage evolution under Beam Raster Scanner conditions for IFMIF

    International Nuclear Information System (INIS)

    Mota, Fernando; Ortiz, Christophe J.; Ibarra, Angel; Vila, Rafael

    2011-01-01

    The formation and evolution of defects in materials irradiated with a homogeneous neutron source and with the Beam Raster Scanner (BRS) solution was investigated. The intensity neutron source fluctuations inherent to the BRS system were determined using the neutron transport McDeLicious code. Defects generated during irradiation were calculated using the binary collision approximation MARLOWE code, using the primary knock-on atom (PKA) energy spectrum resulting from neutron interactions with the material. In order to predict the evolution of defects during irradiation, a Rate Theory model based on ab initio parameters was developed. Our model accounts for the migration of mobile defects, the formation of clusters and their recombination. As an example, we investigated defect evolution in Fe irradiated at room temperature in both beam configurations. Simulation results clearly indicate that the defect evolution expected in the BRS configuration is nearly the same as the one expected in a homogeneous irradiation system.

  16. Durability of reinforced concrete beams strengthened with fiber reinforced polymers under varying environmental conditions

    International Nuclear Information System (INIS)

    El-Sadani, R.A.M.G

    2008-01-01

    Fiber reinforced polymers (FRP) materials were adopted by the aerospace and marine industries, not only for their lightweight and high strength characteristics but also due to their tough and durable nature . As the engineering community has become more familiar with the performance advantages of these materials, new applications have been investigated and implemented. Researches and design guidelines concluded that externally bonded FRP to concrete elements could efficiently increase the capacity of RC elements. Long-term exposure to harsh environments deteriorates concrete and the need for repair and rehabilitation is evident. In order to accept these FRP materials, they must be evaluated for durability in harsh environments. An experimental program was conducted at the materials laboratory- faculty of engineering-Ain Shams university to study the durability of RC beams strengthened with FRP sheets and to compare them with un strengthened beams.The effect of gamma rays on FRP materials and concrete specimens bonded to FRP sheets were also investigated.

  17. Synthesis of arbitrary Fock states via conditional measurement on beam splitters

    International Nuclear Information System (INIS)

    Escher, B.M.; Baseia, B.; Avelar, A.T.

    2005-01-01

    In a previous work [Opt. Commun. 138, 71 (1997)] a scheme was proposed to create traveling fields in the Fock state |2 J >. Here we show how to extend this result to arbitrary Fock states. The procedure combines one-photon states impinging on a sequence of distinct beam splitters, each one associated with a (zero detection) single-photon photodetector, with optimization of the success probability to get the desired state. Advantages and disadvantages of this scheme are discussed

  18. Relationship of upflowing ion beams and conics around the dayside cusp/cleft region to the interplanetary conditions

    Directory of Open Access Journals (Sweden)

    W. Miyake

    2002-04-01

    Full Text Available The dayside cusp/cleft region is known as a major source of upflowing ionospheric ions to the magnetosphere. Since the ions are supposed to be energized by an input of energy from the dayside magnetospheric boundary region, we examined the possible influence of the interplanetary conditions on dayside ion beams and conics observed by the polar-orbiting Exos-D (Akebono satellite. We found that both the solar wind velocity and density, as well as IMF By and Bz , affect the occurrence frequency of ion conics. The energy of ion conics also depends on the solar wind velocity, IMF By and Bz . The ion beams around the local noon are not significantly controlled by the interplanetary conditions. The results reveal that ion convection, as well as the energy source, is important to understand the production of dayside ion conics while that of ion beams basically reflects the intensity of local field-aligned currents.Key words. Ionosphere (particle acceleration – magnetospheric physics (magnetopause, cusp, and boundary layers; magnetosphere ionosphere interaction

  19. Time-dependent plasma behavior triggered by a pulsed electron gun under conditions of beam-plasma-discharge

    International Nuclear Information System (INIS)

    Szuszczewicz, E.P.; Lin, C.S.

    1982-01-01

    This chapter reports on experiments whose purpose was to simulate spaceborne applications of energetic electron guns while exploring the ''in situ'' diagnostics of time-dependent beam-plasma behavior under pulsed electron gun conditions. Beam-plasma-discharge (BPD), the BPD afterglow that exists after gun-pulse termination, and the plasma decay process are considered. It is concluded that there is a rapid enhancement in plasma density as the gas turns on; that during the pulse-ON time a quasi-steady-state BPD can be maintained with characteristics identical with its dc counterpart; that in the period immediately following gun-pulse termination the plasma loss process is dominated by cross-field radial diffusion; and that the afterglow plasma is within + or -10% of being an isodensity contour

  20. Experimental study and simulation of the extraction conditions of a multicharged ion beam from an electron cyclotron resonance source

    International Nuclear Information System (INIS)

    Mandin, J.

    1996-01-01

    This thesis concerns the beam extraction studies of ECR Ion Sources for the SPIRAL project at GANIL (France). The optical properties (i.e. the emittances) of the radioactive ion beam production source is a crucial point in this project. We performed emittance measurements with a very high transport efficiency and developed a computer code for simulating the extraction and transport conditions. This simulation takes into account all the parameters acting on the extraction process: the characteristics of the ions and electrons emitted by the plasma, their space and energy distributions, the space charge, the magnetic filed of the source and the accelerating electric field. We explained the evolution of the emittances for two different types of ECR Ion Source. The simulation-experiment comparison showed us that the magnetic field and the intrinsic energy of the ions seem to be the most important parameters for explaining the overall emittance behaviour of the ECRIS. We precise their values and comment them. (author)

  1. Residual stress in ion implanted titanium nitride studied by parallel beam glancing incidence x-ray diffraction

    International Nuclear Information System (INIS)

    Geist, D.E.; Perry, A.J.; Treglio, J.R.; Valvoda, V.; Rafaja, D.

    1995-01-01

    Ion implantation is known to increase the lifetime of cutting tools. Current theories are the increase in lifetime is caused by an increase in the residual stress, or by work hardening of the surface associated with the implantation. In this work the effect of ion implantation on the residual stress in titanium nitride coatings made by the standard industrial methods of chemical and physical vapor deposition (CVD and PVD) is studied. It is found in the as-received condition (unimplanted), the residual stress levels are near zero for CVD materials and highly compressive, of the order of 6 GPa, for PVD materials. Ion implantation has no effect on the residual stress in the coatings made by CVD. Nitrogen does increase the compressive residual stress by some 10% in the near surface regions of PVD coatings, while nickel-titanium dual metal ion implantation does not have any effect. It appears that the lifetime increase is not associated with residual stress effects

  2. A spatial ecology study on the effects of field conditions and crop rotation on the incidence of Plectris aliena (Coleoptera: Scarabaeidae) grub damage to sweetpotato roots.

    Science.gov (United States)

    Brill, Nancy L; Osborne, Jason; Abney, Mark R

    2013-10-01

    A farmscape study was conducted in commercial sweetpotato (Ipomoea batatas (L.) Lam) fields in Columbus County, NC, in 2010 and 2011 to investigate the effects of the following field conditions: soil drainage class, soil texture, field size, border habitat, land elevation, and the previous year's crop rotation on the incidence of damage caused by Plectris aliena Chapman (Coleoptera:Scarabaeidae) larval feeding. Soil drainage and crop rotation significantly affected the incidence of damage to roots, with well drained soils having a low estimated incidence of damaged roots (0.004) compared with all other drainage classes (0.009-0.011 incidence of damaged roots). Fields with soybeans [Glycine max (L.) Merr] planted the preceding year had the highest incidence of root damage (0.15) compared with all other crops. The effects of border habitats, which were adjacent to grower fields where roots were sampled, showed that as the location of the roots was closer to borders of soybean (planted the year before) or grass fields, the chance of damage to roots decreased. Results indicate that growers can use crop rotation as a management technique and avoid planting sweetpotatoes the year after soybeans to reduce the incidence of P. aliena larval feeding on sweetpotato roots. Environmental conditions such as fields with poor drainage and certain border habitats may be avoided, or selected, by growers to reduce risk of damage to roots by P. aliena.

  3. Improving x-ray fluorescence signal for benchtop polychromatic cone-beam x-ray fluorescence computed tomography by incident x-ray spectrum optimization: a Monte Carlo study.

    Science.gov (United States)

    Manohar, Nivedh; Jones, Bernard L; Cho, Sang Hyun

    2014-10-01

    To develop an accurate and comprehensive Monte Carlo (MC) model of an experimental benchtop polychromatic cone-beam x-ray fluorescence computed tomography (XFCT) setup and apply this MC model to optimize incident x-ray spectrum for improving production/detection of x-ray fluorescence photons from gold nanoparticles (GNPs). A detailed MC model, based on an experimental XFCT system, was created using the Monte Carlo N-Particle (MCNP) transport code. The model was validated by comparing MC results including x-ray fluorescence (XRF) and scatter photon spectra with measured data obtained under identical conditions using 105 kVp cone-beam x-rays filtered by either 1 mm of lead (Pb) or 0.9 mm of tin (Sn). After validation, the model was used to investigate the effects of additional filtration of the incident beam with Pb and Sn. Supplementary incident x-ray spectra, representing heavier filtration (Pb: 2 and 3 mm; Sn: 1, 2, and 3 mm) were computationally generated and used with the model to obtain XRF/scatter spectra. Quasimonochromatic incident x-ray spectra (81, 85, 90, 95, and 100 keV with 10 keV full width at half maximum) were also investigated to determine the ideal energy for distinguishing gold XRF signal from the scatter background. Fluorescence signal-to-dose ratio (FSDR) and fluorescence-normalized scan time (FNST) were used as metrics to assess results. Calculated XRF/scatter spectra for 1-mm Pb and 0.9-mm Sn filters matched (r ≥ 0.996) experimental measurements. Calculated spectra representing additional filtration for both filter materials showed that the spectral hardening improved the FSDR at the expense of requiring a much longer FNST. In general, using Sn instead of Pb, at a given filter thickness, allowed an increase of up to 20% in FSDR, more prominent gold XRF peaks, and up to an order of magnitude decrease in FNST. Simulations using quasimonochromatic spectra suggested that increasing source x-ray energy, in the investigated range of 81-100 ke

  4. Cell inactivation studies on yeast cells under euoxic and hypoxic condition using electron beam from microtron accelerator

    International Nuclear Information System (INIS)

    Praveen Joseph; Santhosh Acharya; Ganesh Sanjeev; Narayana, Y.; Bhat, N.N.

    2011-01-01

    In the case of sparsely ionizing radiation such as electron, the dose rate and the pattern of energy deposition of the radiation are the important physical factors which can affect the amount of damage in living cells. In the present study, the differences in the cell survival efficiency and dose rate effect in diploid yeast strains Saccharomyces cerevisiae X2180 and Saccharomyces cerevisiae D7 under euoxic and hypoxic condition have been quantified. Irradiation was carried out using 8 MeV pulsed electron beam from Microtron accelerator. The dose per pulse and pulse width of the beam used was 0.6 Gy and 2.3 μs, respectively, which correspond to an instantaneous dose rate of 2.6 x 10 5 Gy s -1 . For survival studies doses were delivered at a rate of 50 pulses per second (an average dose rate of 1,800 Gy s -1 ). Fricke and alanine dosimeters were used to measure the dose delivered to the sample. A significant difference in the dose response has been observed under euoxic and hypoxic condition. Dose rate effect has been studied by changing the pulse repetition rate of the Microtron and the dose rate used was from 180 to 1800 Gy min -1 . A significant dose rate effect was observed under euoxic condition for Saccharomyces cerevisiae X2180 but the same was absent under hypoxic condition. The dose rate effect was absent for Saccharomyces cerevisiae D7 under both irradiation condition. The survival curves are found to be sigmoidal in shape under both condition but with a wider shoulder under hypoxic condition. The D 0 value and the Oxygen Enhancement Ratio (OER) at that point have been derived. (author)

  5. Energies and media nr 27. Conditions for the nuclear sector. Incidents this summer in France, Belgium and Germany

    International Nuclear Information System (INIS)

    2008-10-01

    After some comments on recent events in the nuclear sector (agreement between India and the USA, new programs in different countries, activity of French companies abroad), this issue comments the worrying accumulation of incidents which occurred in several French nuclear installations in France (notably on the Tricastin site). It comments the actions of the French nuclear safety authority (ASN), the incident classification, delays in public information, problems faced on fuel assemblies, the issue of subcontracting. Incidents which occurred in Belgium (leakage of radioactive iodine) and Germany (water in an ancient salt and potash mine) are also commented

  6. Modeling of a VMJ PV array under Gaussian high intensity laser power beam condition

    Science.gov (United States)

    Eom, Jeongsook; Kim, Gunzung; Park, Yongwan

    2018-02-01

    The high intensity laser power beaming (HILPB) system is one of the most promising systems in the long-rang wireless power transfer field. The vertical multi-junction photovoltaic (VMJ PV) array converts the HILPB into electricity to power the load or charges a battery. The output power of a VMJ PV array depends mainly on irradiance values of each VMJ PV cells. For simulating an entire VMJ PV array, the irradiance profile of the Gaussian HILPB and the irradiance level of the VMJ PV cell are mathematically modeled first. The VMJ PV array is modeled as a network with dimension m*n, where m represents the number of VMJ PV cells in a column, and n represents the number of VMJ PV cells in a row. In order to validate the results obtained in modeling and simulation, a laboratory setup was developed using 55 VMJ PV array. By using the output power model of VMJ PV array, we can establish an optimal power transmission path by the receiver based on the received signal strength. When the laser beam from multiple transmitters aimed at a VMJ PV array at the same time, the received power is the sum of all energy at a VMJ PV array. The transmitter sends its power characteristics as optically coded laser pulses and powers as HILPB. Using the attenuated power model and output power model of VMJ PV array, the receiver can estimate the maximum receivable powers from the transmitters and select optimal transmitters.

  7. Energy-loss straggling study of proton and alpha-particle beams incident onto ZrO{sub 2} and Al{sub 2}O{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Behar, M.; Fadanelli, R.C. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Porto Alegre, 91501-970 (Brazil); Abril, I. [Departamento de Fisica Aplicada, Universitat d' Alacant, 03080 Alacant (Spain); Garcia-Molina, R. [Departamento de Fisica, Centro de Investigacion en Optica y Nanofisica, Universidad de Murcia, 30100 Murcia (Spain); Nagamine, L.C.C. [Instituto de Fisica, Universidade de Sao Paulo, C.P.66318, 05315-970 Sao Paulo (Brazil)

    2011-10-15

    The energy-loss straggling of zirconia (ZrO{sub 2}) and alumina (Al{sub 2}O{sub 3}) has been experimentally determined for proton and alpha-particle beams mainly by means of the Rutherford backscattering technique and in some few cases using the transmission method. The incident energies of the projectiles covers a wide range, from 200 keV up to 2000 keV for H{sup +} and from 200 keV up to 4000 keV for He{sup +} in zirconia films. In the case of alumina films the studied energy range was 100 keV - 3000 keV for H{sup +} and 100 keV - 6000 keV for He{sup +}. Our experimental results compare very well with theoretical calculations based on the dielectric formalism and a suitable description of the electronic excitation spectrum of ZrO{sub 2} and Al{sub 2}O{sub 3} films through their energy-loss function. (authors)

  8. Reduction of the divergence angle of an incident beam to enhance the demagnification factor of a two-stage acceleration lens in a gas ion nanobeam system of several tens of keV

    Science.gov (United States)

    Ishii, Yasuyuki; Kojima, Takuji

    2018-04-01

    The demagnification factor of a two-stage acceleration lens in a gas ion nanobeam system that produces ion beams with energies in the order of 10 keV was enhanced in this study so that a hydrogen ion beam with a diameter of 115 nm could be produced. The reduction of the divergence angle of the incident beam into the two-stage acceleration lens is the effective method for enhancing the demagnification factor. The divergence angle has been gradually reduced by firstly introducing the preacceleration electrodes to control the divergence angle, namely divergence-angle-control electrodes, and secondly replacing an anode with a modified anode that possesses a Pierce electrode, both of which were in an ion source directly connected to the lens. In this study, the divergence angle of less than 3.6 × 10-4 rad that was previously used to produce a 160-nm hydrogen ion beam with the energy of 46 keV by the above procedure was numerically determined using an ion beam extraction simulation code. The determined minimum divergence angle of the incident ion beam was calculated to be 2.0 × 10-4 rad, which was about half of the previously obtained divergence angle; this was used to experimentally form a hydrogen beam with a diameter of 115 ± 10 nm and the energy of 47 keV. The demagnification factor was estimated to be 1,739 using the newly formed hydrogen beam, which was similar to the simulation result.

  9. Development of chloride-induced corrosion in pre-cracked RC beams under sustained loading: Effect of load-induced cracks, concrete cover, and exposure conditions

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Linwen [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Université de Sherbrooke, Quebec (Canada); François, Raoul, E-mail: raoul.francois@insa-toulouse.fr [Université de Toulouse, UPS, INSA, LMDC, Toulouse (France); Dang, Vu Hiep [Hanoi Architectural University, Faculty of Civil Engineering, Hanoi (Viet Nam); L' Hostis, Valérie [CEA Saclay, CEA, DEN, DPC, SECR, Laboratoire d' Etude du Comportement des Bétons et des Argiles, Gif-sur-Yvette (France); Gagné, Richard [Université de Sherbrooke, Quebec (Canada)

    2015-01-15

    This paper deals with corrosion initiation and propagation in pre-cracked reinforced concrete beams under sustained loading during exposure to a chloride environment. Specimen beams that were cast in 2010 were compared to specimens cast in 1984. The only differences between the two sets of beams were the casting direction in relation to tensile reinforcement and the exposure conditions in the salt-fog chamber. The cracking maps, corrosion maps, chloride profiles, and cross-sectional loss of one group of two beams cast in 2010 were studied and their calculated corrosion rates were compared to that of beams cast in 1984 in order to investigate the factors influencing the natural corrosion process. Experimental results show that, after rapid initiation of corrosion at the crack tip, the corrosion process practically halted and the time elapsing before corrosion resumed depended on the exposure conditions and cover depth.

  10. Fracture assessment of shallow-flaw cruciform beams tested under uniaxial and biaxial loading conditions

    International Nuclear Information System (INIS)

    Bass, B.R.; McAfee, W.J.; Williams, P.T.; Pennell, W.E.

    1999-01-01

    A technology to determine shallow-flaw fracture toughness of reactor pressure vessel (RPV) steels is being developed for application to the safety assessment of RPVs containing postulated shallow surface flaws. Matrices of cruciform beam tests were developed to investigate and quantify the effects of temperature, biaxial loading, and specimen size on fracture initiation toughness of two-dimensional (constant depth), shallow, surface flaws. The cruciform beam specimens were developed at Oak Ridge National Laboratory (ORNL) to introduce a far-field, out-of-plane biaxial stress component in the test section that approximates the nonlinear stresses resulting from pressurized-thermal-shock or pressure-temperature loading of an RPV. Tests were conducted under biaxial load ratios ranging from uniaxial to equibiaxial. These tests demonstrated that biaxial loading can have a pronounced effect on shallow-flaw fracture toughness in the lower transition temperature region for an RPV material. The cruciform fracture toughness data were used to evaluate fracture methodologies for predicting the observed effects of biaxial loading on shallow-flaw fracture toughness. Initial emphasis was placed on assessment of stress-based methodologies, namely, the J-Q formulation, the Dodds-Anderson toughness scaling model, and the Weibull approach. Applications of these methodologies based on the hydrostatic stress fracture criterion indicated an effect of loading-biaxiality on fracture toughness; the conventional maximum principal stress criterion indicated no effect. A three-parameter Weibull model based on the hydrostatic stress criterion is shown to correlate with the experimentally observed biaxial effect on cleavage fracture toughness by providing a scaling mechanism between uniaxial and biaxial loading states. (orig.)

  11. A quantitative evaluation of the L.B.W. efficiency on AISI 304 bead on plates welded under different focusing and tilted laser beam conditions

    Science.gov (United States)

    Daurelio, Giuseppe; Ludovico, Antonio D.; Lugara, M. P.; De Filippis, L. A. C.; Spera, A. M.; Rocco, S.

    2005-03-01

    The aim of this search is to evaluate the WE (Welding Efficiency) of each beads versus the different positions of the laser beam optical focus (positive or negative or zero values) respect to the work-piece surface and also versus different laser beam incidence angles (80° and 70°) by using two laser power levels (2 and 2.5 KW) and two welding speeds (3 and 6 m/min). The WE values have been reported on two DA.LU. method plots and the relate evaluations regarding the same ones as well as the recorded best parameters have been evidenced.

  12. Mg doping of GaN grown by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions

    International Nuclear Information System (INIS)

    Zhang Meng; Bhattacharya, Pallab; Guo Wei; Banerjee, Animesh

    2010-01-01

    Acceptor doping of GaN with Mg during plasma-assisted molecular beam epitaxy, under N-rich conditions and a relatively high growth temperature of 740 deg. C, was investigated. The p-doping level steadily increases with increasing Mg flux. The highest doping level achieved, determined from Hall measurements, is 2.1x10 18 cm -3 . The corresponding doping efficiency and hole mobility are ∼4.9% and 3.7 cm 2 /V s at room temperature. Cross-sectional transmission electron microscopy and photoluminescence measurements confirm good crystalline and optical quality of the Mg-doped layers. An InGaN/GaN quantum dot light emitting diode (λ peak =529 nm) with p-GaN contact layers grown under N-rich condition exhibits a low series resistance of 9.8 Ω.

  13. Why do organizations not learn from incidents? Bottlenecks, causes and conditions for a failure to effectively learn

    DEFF Research Database (Denmark)

    Drupsteen, Linda; Hasle, Peter

    2014-01-01

    be studied.Difficulties were identified in multiple steps of the learning process, but most difficulties became visiblewhen planning actions, which is the phase that bridges the gap from incident investigation to actions forimprovement. The main causes for learning difficulties, which were identified...... learn. In sevenorganizations focus groups were held to discuss factors that according to employees contributed to thefailure to learn. By use of a model of the learning from incidents process, the steps, where difficulties forlearning arose, became visible, and the causes for these difficulties could...

  14. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions

    International Nuclear Information System (INIS)

    Schmidt, M.; Zschornack, G.; Kentsch, U.; Ritter, E.

    2014-01-01

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100 °C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100 °C did not change the magnetic properties of the setup

  15. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, M., E-mail: mike.schmidt@dreebit.com [DREEBIT GmbH, 01109 Dresden (Germany); Zschornack, G.; Kentsch, U.; Ritter, E. [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)

    2014-02-15

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100 °C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100 °C did not change the magnetic properties of the setup.

  16. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions.

    Science.gov (United States)

    Schmidt, M; Zschornack, G; Kentsch, U; Ritter, E

    2014-02-01

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100 °C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100 °C did not change the magnetic properties of the setup.

  17. Temperature conditions for GaAs nanowire formation by Au-assisted molecular beam epitaxy

    International Nuclear Information System (INIS)

    Tchernycheva, M; Harmand, J C; Patriarche, G; Travers, L; Cirlin, G E

    2006-01-01

    Molecular beam epitaxial growth of GaAs nanowires using Au particles as a catalyst was investigated. Prior to the growth during annealing, Au alloyed with Ga coming from the GaAs substrate, and melted. Phase transitions of the resulting particles were observed in situ by reflection high-energy electron diffraction (RHEED). The temperature domain in which GaAs nanowire growth is possible was determined. The lower limit of this domain (320 deg. C) is close to the observed catalyst solidification temperature. Below this temperature, the catalyst is buried by GaAs growth. Above the higher limit (620 deg. C), the catalyst segregates on the surface with no significant nanowire formation. Inside this domain, the influence of growth temperature on the nanowire morphology and crystalline structure was investigated in detail by scanning electron microscopy and transmission electron microscopy. The correlation of the nanowire morphology with the RHEED patterns observed during the growth was established. Wurtzite GaAs was found to be the dominant crystal structure of the wires

  18. Long-Term Flexural Behaviors of GFRP Reinforced Concrete Beams Exposed to Accelerated Aging Exposure Conditions

    Directory of Open Access Journals (Sweden)

    Yeonho Park

    2014-06-01

    Full Text Available This study investigates the impact of accelerated aging conditions on the long-term flexural behavior and ductility of reinforced concrete (RC members with glass fiber-reinforced polymer (GFRP bars (RC-GFRP specimen and steel bars (RC-steel specimen. A total of thirty six specimens were designed with different amounts of reinforcement with three types of reinforcing bars (i.e., helically wrapped GFRP, sand-coated surface GFRP and steel. Eighteen specimens were subjected to sustained loads and accelerated aging conditions (i.e., 47 °C and 80% relative humidity in a chamber. The flexural behavior of specimens under 300-day exposure was compared to that of the companion specimens without experiencing accelerated aging conditions. Results indicate that the accelerated aging conditions reduced flexural capacity in not only RC-steel, but also RC-GFRP specimens, with different rates of reduction. Different types of GFRP reinforcement exhibited different rates of degradation of the flexural capacity when embedded in concrete under the same exposure conditions. Several existing models were compared with experimental results for predicting the deflection and deformability index for specimens. Bischoff and Gross’s model exhibited an excellent prediction of the time-dependent deflections. Except for the deformability index proposed by Jaeger, there was no general trend related to the aging duration. This study recommends the need for further investigation on the prediction of the deformability index.

  19. Possibility of high efficient beam extraction from the CERN SPS with a bent crystal. Simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Scandale, W. [CERN, European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Laboratoire de l' AccelerateurLineaire (LAL), Universite Paris SudOrsay, Orsay (France); INFN Sezione di Roma, Piazzale Aldo Moro 2, 00185 Rome (Italy); Kovalenko, A.D.; Taratin, A.M. [Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation)

    2017-03-11

    The extraction of the SPS beam of 270 GeV/c protons assisted by a bent crystal was studied by simulation. Two methods for delivering the SPS beam onto a crystal were considered: transverse diffusion and orbit bump of the beam. It was shown that the main condition for high efficient beam extraction with a bent crystal, which is a small divergence of the incident beam, can be fulfilled. Extraction efficiency up to 99% can be reached for both methods of the beam delivering. The irradiation of the electrostatic septum wires during the beam extraction can be considerably reduced.

  20. A comparison of simple and realistic eye models for calculation of fluence to dose conversion coefficients in a broad parallel beam incident of protons

    International Nuclear Information System (INIS)

    Sakhaee, Mahmoud; Vejdani-Noghreiyan, Alireza; Ebrahimi-Khankook, Atiyeh

    2015-01-01

    Radiation induced cataract has been demonstrated among people who are exposed to ionizing radiation. To evaluate the deterministic effects of ionizing radiation on the eye lens, several papers dealing with the eye lens dose have been published. ICRP Publication 103 states that the lens of the eye may be more radiosensitive than previously considered. Detailed investigation of the response of the lens showed that there are strong differences in sensitivity to ionizing radiation exposure with respect to cataract induction among the tissues of the lens of the eye. This motivated several groups to look deeper into issue of the dose to a sensitive cell population within the lens, especially for radiations with low energy penetrability that have steep dose gradients inside the lens. Two sophisticated mathematical models of the eye including the inner structure have been designed for the accurate dose estimation in recent years. This study focuses on the calculations of the absorbed doses of different parts of the eye using the stylized models located in UF-ORNL phantom and comparison with the data calculated with the reference computational phantom in a broad parallel beam incident of protons with energies between 20 MeV and 10 GeV. The obtained results indicate that the total lens absorbed doses of reference phantom has good compliance with those of the more sensitive regions of stylized models. However, total eye absorbed dose of these models greatly differ with each other for lower energies. - Highlights: • The validation of reference data for the eye was studied for proton exposures. • Two real mathematical models of the eye were imported into the UF-ORNL phantom. • Fluence to dose conversion coefficients were calculated for different eye sections. • Obtained Results were compared with that of assessed by ICRP adult male phantom

  1. Tomosynthesis can facilitate accurate measurement of joint space width under the condition of the oblique incidence of X-rays in patients with rheumatoid arthritis.

    Science.gov (United States)

    Ono, Yohei; Kashihara, Rina; Yasojima, Nobutoshi; Kasahara, Hideki; Shimizu, Yuka; Tamura, Kenichi; Tsutsumi, Kaori; Sutherland, Kenneth; Koike, Takao; Kamishima, Tamotsu

    2016-06-01

    Accurate evaluation of joint space width (JSW) is important in the assessment of rheumatoid arthritis (RA). In clinical radiography of bilateral hands, the oblique incidence of X-rays is unavoidable, which may cause perceptional or measurement error of JSW. The objective of this study was to examine whether tomosynthesis, a recently developed modality, can facilitate a more accurate evaluation of JSW than radiography under the condition of oblique incidence of X-rays. We investigated quantitative errors derived from the oblique incidence of X-rays by imaging phantoms simulating various finger joint spaces using radiographs and tomosynthesis images. We then compared the qualitative results of the modified total Sharp score of a total of 320 joints from 20 patients with RA between these modalities. A quantitative error was prominent when the location of the phantom was shifted along the JSW direction. Modified total Sharp scores of tomosynthesis images were significantly higher than those of radiography, that is to say JSW was regarded as narrower in tomosynthesis than in radiography when finger joints were located where the oblique incidence of X-rays is expected in the JSW direction. Tomosynthesis can facilitate accurate evaluation of JSW in finger joints of patients with RA, even with oblique incidence of X-rays. Accurate evaluation of JSW is necessary for the management of patients with RA. Through phantom and clinical studies, we demonstrate that tomosynthesis may achieve more accurate evaluation of JSW.

  2. LHCb: Beam and Background Monitoring and the Development of an Online Condition Analysis Tool for the LHCb Experiment at CERN

    CERN Multimedia

    Alessio, F

    2010-01-01

    The LHCb experiment has been taking data since more than half a year at the LHC, recording events from collisions at the highest energy ever achieved. For its physics purposes in the sector of CP violation, the experiment will record data with the best precision achievable. An online and offline beam and background monitoring became therefore essential to understand the performance of the LHC accelerator at CERN, to monitor and study the behavior of the background around the LHCb experiment and to optimize the experimental conditions. During my second year as a Doctoral Student at CERN, I have been working on the timing and readout control as well as on the online Beam, Background, and Luminosity Monitoring of the LHCb experiment in the frame of the LHCb Online group. The group is responsible for the complete data acquisition of the LHCb experiment, from the Front-End Electronics (FEE) to the storage of the data for offline analysis, including the Timing and Fast Control (TFC) system. The latter controls and...

  3. Efficacy of Thermally Conditioned Sisal FRP Composite on the Shear Characteristics of Reinforced Concrete Beams

    OpenAIRE

    Sen, Tara; Reddy, H. N. Jagannatha

    2013-01-01

    The development of commercially viable composites based on natural resources for a wide range of applications is on the rise. Efforts include new methods of production and the utilization of natural reinforcements to make biodegradable composites with lignocellulosic fibers, for various engineering applications. In this work, thermal conditioning of woven sisal fibre was carried out, followed by the development of woven sisal fibre reinforced polymer composite system, and its tensile and flex...

  4. A Comparison of the Conditioning Regimens BEAM and FEAM for Autologous Hematopoietic Stem Cell Transplantation in Lymphoma: an Observational Study on Patients From Fondazione Italiana Linfomi (Fil).

    Science.gov (United States)

    Olivieri, Jacopo; Mosna, Federico; Pelosini, Matteo; Fama, Angelo; Rattotti, Sara; Giannoccaro, Margherita; Carli, Giuseppe; Tisi, Maria Chiara; Ferrero, Simone; Sgherza, Nicola; Mazzone, Anna Maria; Marino, Dario; Calimeri, Teresa; Loseto, Giacomo; Saraceni, Francesco; Tomei, Gabriella; Sica, Simona; Perali, Giulia; Codeluppi, Katia; Billio, Atto; Olivieri, Attilio; Orciuolo, Enrico; Matera, Rossella; Stefani, Piero Maria; Borghero, Carlo; Ghione, Paola; Cascavilla, Nicola; Lanza, Francesco; Chiusolo, Patrizia; Finotto, Silvia; Federici, Irene; Gherlinzoni, Filippo; Centurioni, Riccardo; Fanin, Renato; Zaja, Francesco

    2018-05-29

    Carmustine (BCNU)-Etoposide-Citarabine-Melphalan (BEAM) chemotherapy is the standard conditioning regimen for autologous stem cell transplantation (ASCT) in lymphomas. Owing to BCNU shortages, many centers switched to Fotemustine-substituted BEAM (FEAM), lacking proof of equivalence. We conducted a retrospective cohort study in 18 Italian centers to compare safety and efficacy of BEAM and FEAM regimens for ASCT in lymphomas performed from 2008 to 2015. We enrolled 1038 patients (BEAM n=607, FEAM n=431), of which 27% had Hodgkin's lymphoma (HL), 14% indolent Non-Hodgkin's lymphoma (iNHL) and 59% aggressive NHL (aNHL). Baseline characteristics including age, sex, stage, B-symptoms, extranodal involvement, previous treatments, response before ASCT, overall conditioning intensity, were well balanced between BEAM and FEAM; notable exceptions were: ASCT year (median: BEAM=2011 vs FEAM=2013, p<0.001), Sorror score (≥3: BEAM=15% vs FEAM=10%, p=0.017), radiotherapy use (BEAM=18% vs FEAM=10%, p<0.001). FEAM conditioning resulted in higher rates of gastrointestinal and infectious toxicities, including severe oral mucositis (grade ≥3: BEAM=31% vs FEAM=44%, p<0.001), and sepsis from Gram-negative bacteria (mean isolates/patient: BEAM=0.1 vs FEAM=0.19, p<0.001). Response status at day 100 post-ASCT (overall response: BEAM=91% vs FEAM=88%, p=0.42), 2-years Overall Survival (83.9%, 95%CI:81.5%-86.1%) and Progression-free Survival (70.3%, 95%CI:67.4%-73.1%) were not different in the two groups. Mortality from infection was higher in the FEAM group (SHR 1.99; 95%CI:1.02-3.88, p=0.04). BEAM and FEAM do not appear different in terms of survival and disease control. However, due to concerns of higher toxicity, Fotemustine substitution in BEAM does not seem justified, if not for easier supply. Copyright © 2018. Published by Elsevier Inc.

  5. Optimal conditions for high current proton irradiations at the university of Wisconsin's ion beam laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Wetteland, C. J.; Field, K. G.; Gerczak, T. J. [Materials Science Program, University of Wisconsin, Madison, WI 53706 (United States); Eiden, T. J.; Maier, B. R.; Albakri, O.; Sridharan, K.; Allen, T. R. [Department of Engineering Physics, University of Wisconsin, Madison, WI 53706 (United States)

    2013-04-19

    The National Electrostatics Corporation's (NEC) Toroidal Volume Ion Source (TORVIS) source is known for exceptionally high proton currents with minimal service downtime as compared to traditional sputter sources. It has been possible to obtain over 150{mu}A of proton current from the source, with over 70{mu}A on the target stage. However, beam fluxes above {approx}1 Multiplication-Sign 10{sup 17}/m2-s may have many undesirable effects, especially for insulators. This may include high temperature gradients at the surface, sputtering, surface discharge, cracking or even disintegration of the sample. A series of experiments were conducted to examine the role of high current fluxes in a suite of ceramics and insulating materials. Results will show the optimal proton irradiation conditions and target mounting strategies needed to minimize unwanted macro-scale damage, while developing a procedure for conducting preliminary radiation experiments.

  6. In vitro H2AX phosphorylation and micronuclei induction in human fibroblasts across the Bragg curve of a 577MeV/nucleon Fe incident beam

    Energy Technology Data Exchange (ETDEWEB)

    Desai, N. [NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX (United States); Sodolak, J. [Prairie View A and M University, Prairie View, TX (United States); Gersey, B. [Prairie View A and M University, Prairie View, TX (United States); Durante, M. [University Federico II, Naples (Italy); Lin, Z.W. [University of Alabama in Huntsville, Huntsville, AL (United States); Rusek, A. [Brookhaven National Laboratory, Upton, NY (United States); Cucinotta, F.A. [NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX (United States); Wu, H. [NASA Johnson Space Center, 2101 NASA Parkway, Houston, TX (United States)]. E-mail: honglu.wu-1@nasa.gov

    2006-10-15

    The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the only major protection to astronauts from harmful exposure. Unlike low-linear energy transfer (LET) {gamma} or X-rays, the presence of shielding does not always reduce the radiation risks for energetic charged particle exposure, since the dose delivered by the charged particle increases sharply as the particle approaches the end of its range, a position known as the Bragg peak. The Bragg curve does not necessarily represent the biological damage along the particle traversal, and the 'biological Bragg curve' is dependent on the energy and the type of the primary particle, and may vary for different biological endpoints. Here we used a unique irradiation geometry to measure the biological response across the Bragg curve in human fibroblasts exposed to 577MeV/nucleon incident Fe ions in vitro. Polyethylene shielding was used to achieve a Bragg curve distribution with the beam geometry parallel to a monolayer of fibroblast cells. Qualitative analyses of {gamma}-H2AX fluorescence, a known marker of DSBs, indicated increased clustering of DNA damage before the Bragg peak, enhanced homogenous distribution at the peak, and provided visual evidence of high-LET particle traversal of cells beyond the Bragg peak in agreement with one-dimensional transport approximations. A quantitative biological response curve generated for micronuclei induction across the Bragg curve did not reveal an increased yield of micronuclei at the location of the Bragg peak. However, the percentage of mononucleated cells, which indicates inhibition in cell progression, increased at the location of the peak. These results confirm the argument that severely damaged cells at the Bragg peak, as observed by increased {gamma}-H2AX formation, are likely to go through reproduction death. Depending on the LET value of the primary particles, the yield of

  7. Condições de saúde, incidência de quedas e nível de atividade física dos idosos Health conditions, incidence of falls and physical activity levels among the elderly

    Directory of Open Access Journals (Sweden)

    GZ Mazo

    2007-12-01

    Full Text Available OBJETIVO: Relacionar o nível de atividade física e a incidência de quedas com as condições de saúde dos idosos de grupos de convivência. MÉTODO: Pesquisa descritiva transversal. Amostra de 256 idosos, 219 do sexo feminino e 37 do masculino, com média de idade de 70,85 anos. Para coleta dos dados foram utilizados um formulário com perguntas sobre as condições de saúde, quedas e o Questionário Internacional de Atividade Física (IPAQ. A análise se deu por meio de estatística descritiva e de teste não-paramétrico (qui-quadrado, adotando-se um nível de significância de 5%. RESULTADOS: 201 idosos (79,13% foram classificados como muito ativos. Desses, apenas 38 idosos haviam sofrido quedas nos últimos três meses. Houve relação estatisticamente significativa entre o nível de atividade física pouco ativo com o número de quedas e com a condição de saúde atual (p= 0,011. A condição de saúde se associou negativamente com a prática de atividade física (p= 0,016 e com a satisfação com a saúde (p= 0,05. Dos idosos pouco ativos que tiveram queda, 50% relataram que sua saúde atual é ruim. Todos os idosos pouco ativos que sofreram quedas disseram que sua condição de saúde atual dificulta a prática de atividade física, e apenas 20% deles estão satisfeitos com sua saúde. CONCLUSÃO: A prática regular de atividade física parece estar associada a uma melhor condição de saúde dos idosos e uma menor incidência de quedas.OBJECTIVE: To relate the physical activity levels and incidence of falls among elderly people in social groups, to their health conditions. METHOD: This was a cross-sectional descriptive study on a sample of 256 elderly people (219 females and 37 males of mean age 70.85 years. A form containing questions about health conditions, falls and the International Physical Activity Questionnaire (IPAQ were used for data collection. The analysis consisted of descriptive statistics and a non-parametric test

  8. Visualization of the influence of the air conditioning system to the high-power laser beam quality with the modulation coherent imaging method.

    Science.gov (United States)

    Tao, Hua; Veetil, Suhas P; Pan, Xingchen; Liu, Cheng; Zhu, Jianqiang

    2015-08-01

    Air conditioning systems can lead to dynamic phase change in the laser beams of high-power laser facilities for the inertial confinement fusion, and this kind of phase change cannot be measured by most of the commonly employed Hartmann wavefront sensor or interferometry due to some uncontrollable factors, such as too large laser beam diameters and the limited space of the facility. It is demonstrated that this problem can be solved using a scheme based on modulation coherent imaging, and thus the influence of the air conditioning system on the performance of the high-power facility can be evaluated directly.

  9. Beam diagnostics on ARGUS

    International Nuclear Information System (INIS)

    MacQuigg, D.R.; Speck, D.R.

    1976-01-01

    Performance of laser fusion targets depends critically on the characteristics of the incident beam. The spatial distribution and temporal behavior of the light incident on the target varies significantly with power, with choice of beam spatial profile and with location of spatial filters. On each ARGUS shot we photograph planes in the incident beams which are equivalent to the target plane. Array cameras record the time integrated energy distributions and streak cameras record the temporal behavior. Computer reduction of the photographic data provides detailed spatial energy distributions, and instantaneous power on target vs. time. Target performance correlates with the observed beam characteristics

  10. Uniformity of the soft-x-ray emissions from gold foils irradiated by OMEGA laser beams determined by a two-mirror normal-incidence microscope with multilayer coatings

    International Nuclear Information System (INIS)

    Seely, John F.; Boehly, Thomas; Pien, Gregory; Bradley, David

    1998-01-01

    A two-mirror normal-incidence microscope with multilayer coatings was used to image the soft-x-ray emissions from planar foils irradiated by OMEGA laser beams. The bandpass of the multilayer coatings was centered at a wavelength of 48.3 Angstrom (257-eV energy) and was 0.5 Angstrom wide. Five overlapping OMEGA beams, without beam smoothing, were typically incident on the gold foils. The total energy was 1500 J, and the focused intensity was 6x10 13 Wcm -2 . The 5.8x magnified images were recorded by a gated framing camera at various times during the 3-ns laser pulse. A pinhole camera imaged the x-ray emission in the energy range of >2 keV. On a spatial scale of 10 μm, it was found that the soft-x-ray images at 257 eV were quite uniform and featureless. In contrast, the hard-x-ray images in the energy range of >2 kev were highly nonuniform with numerous features of size 150 μm. copyright 1998 Optical Society of America

  11. Optics with an Atom Laser Beam

    International Nuclear Information System (INIS)

    Bloch, Immanuel; Koehl, Michael; Greiner, Markus; Haensch, Theodor W.; Esslinger, Tilman

    2001-01-01

    We report on the atom optical manipulation of an atom laser beam. Reflection, focusing, and its storage in a resonator are demonstrated. Precise and versatile mechanical control over an atom laser beam propagating in an inhomogeneous magnetic field is achieved by optically inducing spin flips between atomic ground states with different magnetic moment. The magnetic force acting on the atoms can thereby be effectively switched on and off. The surface of the atom optical element is determined by the resonance condition for the spin flip in the inhomogeneous magnetic field. More than 98% of the incident atom laser beam is reflected specularly

  12. Beam-Beam Effects

    International Nuclear Information System (INIS)

    Herr, W; Pieloni, T

    2014-01-01

    One of the most severe limitations in high-intensity particle colliders is the beam-beam interaction, i.e. the perturbation of the beams as they cross the opposing beams. This introduction to beam-beam effects concentrates on a description of the phenomena that are present in modern colliding beam facilities

  13. Comparison of additional boundary conditions based on thermoreflectance spectra of the Asub(n=1)-exciton in CdS crystals at oblique incidence

    International Nuclear Information System (INIS)

    Stoessel, W.; Wagner, H.J.

    1978-01-01

    Thermoreflectance spectra of the Asub(n=1)-exciton in CdS are measured at 8 K for angles of incidence of the light ranging from 5 0 to 85 0 , using three different spatial arrangements between the c-axis, the E- and k-vector of light. Additional boundary conditions of Pekar, Ting et al. Agarwal et al. are discussed for the first time in terms of optical constants. The refractive indices for these additional boundary conditions are derived, considering special features of CdS, such as optical anisotropy, exciton symmetry, and effective exciton mass anisotropy. Fitting calculations based on the experimental data show that Pekar's additional boundary condition gives the best agreement between theory and experiment. (author)

  14. Increasing incidence of statin treatmentamong the elderly and those withoutprevious cardiovascular conditions. A nationwide register study

    DEFF Research Database (Denmark)

    Kildemoes, Helle Wallach; Andersen, Morten

      Background: Supported by the growing evidence of the beneficial effects of statins in a range of conditions, statin utilization has increased considerably in most Western countries over the last decade. Objectives: To estimate to what extent a widening of indication scope for statins accounts...... with discharge diagnoses and surgical procedures performed during 1977-2005. The disease status for all cohort members was assigned by means of disease markers for seven cardiovascular conditions, corresponding to a hierarchy of broad indications for statin therapy. Using the indication hierarchy, we computed...

  15. Factors affecting the possibility to detect buccal bone condition around dental implants using cone beam computed tomography

    DEFF Research Database (Denmark)

    Liedke, Gabriela S; Spin-Neto, Rubens; da Silveira, Heloisa E D

    2016-01-01

    OBJECTIVES: To evaluate factors with impact on the conspicuity (possibility to detect) of the buccal bone condition around dental implants in cone beam computed tomography (CBCT) imaging. MATERIAL AND METHODS: Titanium (Ti) or zirconia (Zr) implants and abutments were inserted into 40 bone blocks...... in a way to obtain variable buccal bone thicknesses. Three combinations regarding the implant-abutment metal (TiTi, TiZr, or ZrZr) and the number of implants (one, two, or three) were assessed. Two CBCT units (Scanora 3D - Sc and Cranex 3D - Cr) and two voxel resolutions (0.2 and 0.13 mm) were used...... variable. Odds ratio (OR) were calculated separately for each CBCT unit. RESULTS: Implant-abutment combination (ZrZr) (OR Sc = 19.18, OR Cr = 11.89) and number of implants (3) (OR Sc = 12.10, OR Cr = 4.25) had major impact on buccal bone conspicuity. The thinner the buccal bone, the higher the risk...

  16. Scattering of H(D) from LiF(1 0 0) under fast grazing incidence conditions: To what extent is classical dynamics a useful tool?

    Energy Technology Data Exchange (ETDEWEB)

    Muzas, A.S. [Departamento de Química Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Martín, F. [Departamento de Química Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid (Spain); Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-nanociencia), Cantoblanco, 28049 Madrid (Spain); Díaz, C., E-mail: cristina.diaz@uam.es [Departamento de Química Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid (Spain)

    2015-07-01

    Diffraction experiments of atoms and molecules under fast grazing incidence conditions have opened a new field in surface science. This experimental effort calls for complementary theoretical studies, which would allow a detailed analysis of experimental data. Here, we have analyzed the ability of classical dynamics simulations to reproduce experimental results. To perform this study, a DFT (density functional theory) based potential energy surface, describing the interaction between a H atom and a LiF(1 0 0) surface, has been computed. Diffraction probabilities have been simulated by means of a classical binning method. Our results have been found to be in qualitative good agreement with recent experimental measurements.

  17. ANALYSIS OF THE INCIDENCE AND STRUCTURE OF THE CARDIOVASCULAR SYSTEM DISEASES IN THE FAR NORTH MIGRANTS OVER THE PERIOD OF READAPTATION TO THE NEW CLIMATIC CONDITIONS

    Directory of Open Access Journals (Sweden)

    Roman Anatolyevich Yaskevich

    2017-12-01

    Full Text Available The purpose of the study. To study the frequency and structure of cardiovascular diseases of the Far North migrants within the period of readaptation to the new climatic conditions. Materials and methods. 145 migrants with stages II–III of arterial hypertension (AH coming from the Far North arrived in the southern regions of central Siberia for permanent residence. The survey included questionnaires, clinical, instrumental, and functional and laboratory research methods. Results. After moving to central Siberia, the hypertensive crisis is more common in people who lived in the Far North for 30 years or more. An increase in the hypertensive crisis frequency was observed in men, rather than women, whereas the stroke incidence in female migrants gets higher, but remains unchanged in male migrants. An increase in the incidence of diseases that complicate the hypertension progression was detected in the migrants during the period following the migration. An increase in the incidence of angina attacks and strokes as well as a trend towards an increase in the incidence of myocardial infarction and heart failure after moving to central Siberia is caused by an increase in the level of neurotic disorders associated with social and economic factors. Conclusion. The identified patterns should be taken into account in the construction of prevention and rehabilitation programs for the Far North migrants along with an obligatory assessment of the adaptive and readaptive capabilities of the organism. Both the follow-up plan and the list of the required measures should be made individually, while taking into account the identified cardiovascular diseases, concomitant pathology and risk factors. Should the migrant be diagnosed with any cardiovascular diseases, they need to consult a cardiologist with the purpose of correcting both medicated and medication-free therapy for the readaptation period.

  18. Effect of laser beam conditioning on fabrication of clean micro-channel on stainless steel 316L using second harmonic of Q-switched Nd:YAG laser

    Science.gov (United States)

    Singh, Sanasam Sunderlal; Baruah, Prahlad Kr; Khare, Alika; Joshi, Shrikrishna N.

    2018-02-01

    Laser micromachining of metals for fabrication of micro-channels generate ridge formation along the edges accompanied by ripples along the channel bed. The ridge formation is due to the formation of interference pattern formed by back reflections from the beam splitter and other optical components involved before focusing on the work piece. This problem can be curtailed by using a suitable aperture or Iris diaphragm so as to cut the unwanted portion of the laser beam before illuminating the sample. This paper reports an experimental investigation on minimizing this problem by conditioning the laser beam using an Iris diaphragm and using optimum process parameters. In this work, systematic experiments have been carried out using the second harmonic of a Q-switched Nd:YAG laser to fabricate micro-channels. Initial experiments revealed that formation of ridges along the sides of micro-channel can easily be minimized with the help of Iris diaphragm. Further it is noted that a clean micro-channel of depth 43.39 μm, width up to 64.49 μm and of good surface quality with average surface roughness (Ra) value of 370 nm can be machined on stainless steel (SS) 316L by employing optimum process condition: laser beam energy of 30 mJ/pulse, 11 number of laser scans and scan speed of 169.54 μm/s with an opening of 4 mm diameter of Iris diaphragm in the path of the laser beam.

  19. Effects of deposition and post-annealing conditions on electrical properties and thermal stability of TiAlN films by ion beam sputter deposition

    International Nuclear Information System (INIS)

    Lee, S.-Y.; Wang, S.-C.; Chen, J.-S.; Huang, J.-L.

    2006-01-01

    TiAlN films were deposited by ion beam sputter deposition (IBSD) using a Ti-Al (90/10) alloy target in a nitrogen atmosphere on thermal oxidized Si wafers. Effects of ion beam voltage, substrate temperature (T s ) and post-annealing conditions on electrical properties and oxidation resistance of TiAlN films were studied. According to the experimental results, the proper kinetic energy provided good crystallinity and a dense structure of the films. Because of their better crystallinity and predomination of (200) planes, TiAlN films deposited with 900 V at low T s (50 deg. C) have shown lower resistivity than those at high T s (250 deg. C). They also showed better oxidation resistance. If the beam voltage was too high, it caused some damage to the film surfaces, which caused poor oxidation resistance of films. When sufficient kinetic energy was provided by the beam voltage, the mobility of adatoms was too high due to their extra thermal energy, thus reducing the crystallinity and structure density of the films. A beam voltage of 900 V and a substrate temperature of 50 deg. C were the optimum deposition conditions used in this research. They provided good oxidation resistance and low electrical resistivity for IBSD TiAlN films

  20. Extension of filament propagation in water with Bessel-Gaussian beams

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, G.; Sayrac, M.; Boran, Y.; Kolomenskii, A. A. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); Kaya, N.; Schuessler, H. A. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); Science and Petroleum, Texas A& M University at Qatar, Doha 23874 (Qatar); Strohaber, J. [Department of Physics, Texas A& M University, College Station, Texas 77843 (United States); Department of Physics, Florida A& M University, Tallahassee, Florida 32307 (United States); Amani, M. [Science and Petroleum, Texas A& M University at Qatar, Doha 23874 (Qatar)

    2016-03-15

    We experimentally studied intense femtosecond pulse filamentation and propagation in water for Bessel-Gaussian beams with different numbers of radial modal lobes. The transverse modes of the incident Bessel-Gaussian beam were created from a Gaussian beam of a Ti:sapphire laser system by using computer generated hologram techniques. We found that filament propagation length increased with increasing number of lobes under the conditions of the same peak intensity, pulse duration, and the size of the central peak of the incident beam, suggesting that the radial modal lobes may serve as an energy reservoir for the filaments formed by the central intensity peak.

  1. Extension of filament propagation in water with Bessel-Gaussian beams

    Directory of Open Access Journals (Sweden)

    G. Kaya

    2016-03-01

    Full Text Available We experimentally studied intense femtosecond pulse filamentation and propagation in water for Bessel-Gaussian beams with different numbers of radial modal lobes. The transverse modes of the incident Bessel-Gaussian beam were created from a Gaussian beam of a Ti:sapphire laser system by using computer generated hologram techniques. We found that filament propagation length increased with increasing number of lobes under the conditions of the same peak intensity, pulse duration, and the size of the central peak of the incident beam, suggesting that the radial modal lobes may serve as an energy reservoir for the filaments formed by the central intensity peak.

  2. Charged corpuscular beam detector

    Energy Technology Data Exchange (ETDEWEB)

    Hikawa, H; Nishikawa, Y

    1970-09-29

    The present invention relates to a charged particle beam detector which prevents transient phenomena disturbing the path and focusing of a charged particle beam travelling through a mounted axle. The present invention provides a charged particle beam detector capable of decreasing its reaction to the charge in energy of the charged particle beam even if the relative angle between the mounted axle and the scanner is unstable. The detector is characterized by mounting electrically conductive metal pieces of high melting point onto the face of a stepped, heat-resistant electric insulating material such that the pieces partially overlap each other and individually provide electric signals, whereby the detector is no longer affected by the beam. The thickness of the metal piece is selected so that an eddy current is not induced therein by an incident beam, thus the incident beam is not affected. The detector is capable of detecting a misaligned beam since the metal pieces partially overlap each other.

  3. Ageing, exposure to pollution, and interactions between climate change and local seasons as oxidant conditions predicting incident hematologic malignancy at KINSHASA University clinics, Democratic Republic of CONGO (DRC).

    Science.gov (United States)

    Nkanga, Mireille Solange Nganga; Longo-Mbenza, Benjamin; Adeniyi, Oladele Vincent; Ngwidiwo, Jacques Bikaula; Katawandja, Antoine Lufimbo; Kazadi, Paul Roger Beia; Nzonzila, Alain Nganga

    2017-08-23

    The global burden of hematologic malignancy (HM) is rapidly rising with aging, exposure to polluted environments, and global and local climate variability all being well-established conditions of oxidative stress. However, there is currently no information on the extent and predictors of HM at Kinshasa University Clinics (KUC), DR Congo (DRC). This study evaluated the impact of bio-clinical factors, exposure to polluted environments, and interactions between global climate changes (EL Nino and La Nina) and local climate (dry and rainy seasons) on the incidence of HM. This hospital-based prospective cohort study was conducted at Kinshasa University Clinics in DR Congo. A total of 105 black African adult patients with anaemia between 2009 and 2016 were included. HM was confirmed by morphological typing according to the French-American-British (FAB) Classification System. Gender, age, exposure to traffic pollution and garages/stations, global climate variability (El Nino and La Nina), and local climate (dry and rainy seasons) were potential independent variables to predict incident HM using Cox regression analysis and Kaplan Meier curves. Out of the total 105 patients, 63 experienced incident HM, with an incidence rate of 60%. After adjusting for gender, HIV/AIDS, and other bio-clinical factors, the most significant independent predictors of HM were age ≥ 55 years (HR = 2.4; 95% CI 1.4-4.3; P = 0.003), exposure to pollution and garages or stations (HR = 4.9; 95% CI 2-12.1; P pollution, combined local dry season + La Nina and combined local dry season + El Nino were the most significant predictors of incident hematologic malignancy. These findings highlight the importance of aging, pollution, the dry season, El Nino and La Nina as related to global warming as determinants of hematologic malignancies among African patients from Kinshasa, DR Congo. Cancer registries in DRC and other African countries will provide more robust database for future researches on

  4. Behaviour of high purity UO2/H2O interfaces under helium beam irradiation in deaerated conditions

    International Nuclear Information System (INIS)

    Mendes, E.

    2005-11-01

    A question put within the framework of the nuclear fuel storage worn in geological site is what become to them in the presence of water. The aim of a fundamental program, of PRECCI project (ECA), is to highlight the behaviour of interfaces which can be used as models for the interfaces nuclear spent fuel/water if the fuel is uranium UO 2 dioxide. This doctorate is interested in the effect of the alpha activity which is the only one that exist in the spent fuel after long periods. The aim is to identify the mechanisms of alteration and of leaching of surfaces under alpha irradiation. A method is developed to irradiate UO 2 /H 2 O interfaces in deaerated conditions with the beam of He 2+ produced by a cyclotron. The He 2+ ions cross an UO 2 disc and emerge in water with an energy of 5 MeV. Leachings under irradiation are carried with a large range of particles flux. The post-irradiation characterization of the surface of the discs realised by micro-Raman spectroscopy allowed to identify the alteration layer. It is made up of studtite UO 2 (O 2 ),4H 2 O, and of schoepite UO 3 ,xH 2 O. The analysis of the solutions shows that the uranium release strongly increases. The electrochemical properties of the interfaces under irradiation strongly differ from those before irradiation. This work allows to propose that the radiolytic species seen by the interface are it during the heterogeneous phase of evolution of the traces and are species of short lives. Modeling show that the radiolytic radicals species can migrate toward the interface and react with the UO 2 surface. (author)

  5. Unequal Exposure or Unequal Vulnerability? Contributions of Neighborhood Conditions and Cardiovascular Risk Factors to Socioeconomic Inequality in Incident Cardiovascular Disease in the Multi-Ethnic Study of Atherosclerosis.

    Science.gov (United States)

    Hussein, Mustafa; Diez Roux, Ana V; Mujahid, Mahasin S; Hastert, Theresa A; Kershaw, Kiarri N; Bertoni, Alain G; Baylin, Ana

    2017-11-23

    Risk factors can drive socioeconomic inequalities in cardiovascular disease (CVD) through differential exposure and differential vulnerability. We show how econometric decomposition directly enables simultaneous, policy-oriented assessment of these two mechanisms. We specifically estimated contributions via these mechanisms of neighborhood environment and proximal risk factors to socioeconomic inequality in CVD incidence. We followed 5,608 participants in the Multi-Ethnic Study of Atherosclerosis (2000-2012) until the first CVD event (median follow-up 12.2 years). We used a summary measure of baseline socioeconomic position (SEP). Covariates included baseline demographics, neighborhood, psychosocial, behavioral, and biomedical risk factors. Using Poisson models, we decomposed the difference (inequality) in incidence rates between low- and high-SEP groups into contributions of 1) differences in covariate means (differential exposure), and 2) differences in CVD risk associated with covariates (differential vulnerability). Notwithstanding large uncertainty in neighborhood estimates, our analysis suggests that differential exposure to poorer neighborhood socioeconomic conditions, adverse social environment, diabetes, and hypertension accounts for most of inequality. Psychosocial and behavioral contributions were negligible. Further, neighborhood SEP, female gender, and White race were more strongly associated with CVD among low-SEP (vs. high-SEP) participants. These differentials in vulnerability also accounted for nontrivial portions of the inequality, and could have important implications for intervention. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Comparing the risk associated with psychosocial work conditions and health behaviours on incident hypertension over a nine-year period in Ontario, Canada.

    Science.gov (United States)

    Smith, Peter M; Mustard, Cameron A; Lu, Hong; Glazier, Richard H

    2013-01-07

    Hypertension is an increasingly important health concern in Canada. This paper examines the risks associated with psychosocial working conditions compared to health behaviours on the risk of hypertension over a 9-year period in Ontario, Canada. We used data from Ontario respondents to the 2000-01 Canadian Community Health Survey linked to the Ontario Health Information Plan database covering physician services and the Canadian Institute for Health Information database for hospital admissions. We focused on labour market participants aged 35 to 60, who had not been previously diagnosed with hypertension, were not self-employed, and were working more than 10 hours per week, more than 20 weeks in the previous 12 months (N = 6,611). Subjects were followed for a nine-year period to ascertain incidence of hypertension. Low job control was associated with an increased risk of hypertension among men, but not among women. The population attributable fraction associated with low job control among males was 11.8% in our fully adjusted model. There was no consistent pattern of increased risk of hypertension across different levels of health behaviours. Primary prevention efforts to reduce the incidence of hypertension predominantly target modifiable health behaviours. Evidence from this longitudinal cohort suggests that modifiable characteristics of the work environment should also be considered in the design of cardiovascular disease prevention programs, in particular for male labour market participants.

  7. Incidence of the phenomena El Nino and The Nina, on the climatic conditions in the valley of the River Cauca. Part I - climatological Analysis

    International Nuclear Information System (INIS)

    Pena Quinones Andres Javier; Cortes Betancourt, Enrique; Montealegre Leon, Fernando

    2001-01-01

    The influence of the phenomena known as El Nino and La Nina on the climatic conditions in the Cauca Valley (South-western Colombia) was studied by means of the analysis of climatic variability caused by these phenomena. Data were analysed from three weather stations located in the sugarcane area of influence, recorded during the 1972-1998 period. It was found that when these events are present in the Tropical Pacific Ocean, the behaviour of some climatic variables in the Cauca Valley is altered. These anomalies, which are of different magnitude for the different climatic variables, tend to be opposite in nature. The incidence of these phenomena on the Cauca Valley climate is noticeable in certain seasons and months

  8. Time-resolved Shielded-Pickup Measurements and Modeling of Beam Conditioning Effects on Electron Cloud Buildup at CesrTA

    CERN Document Server

    Crittenden, J A; Liu, X; Palmer, M A; Santos, S; Sikora, J P; Kato, S; Calatroni, S; Rumolo, G

    2012-01-01

    The Cornell Electron Storage Ring Test Accelerator program includes investigations into electron cloud buildup in vacuum chambers with various coatings. Two 1.1-mlong sections located symmetrically in the east and west arc regions are equipped with BPM-like pickup detectors shielded against the direct beam-induced signal. They detect cloud electrons migrating through an 18-mm-diameter pattern of 0.76 mm-diameter holes in the top of the chamber. A digitizing oscilloscope is used to record the signals, providing time-resolved information on cloud development. We present new measurements of the effect of beam conditioning on a newly-installed amorphous carbon coated chamber, as well as on an extensively conditioned chamber with a diamond-like carbon coating. The ECLOUD modeling code is used to quantify the sensitivity of these measurements to model parameters, differentiating between photoelectron and secondary-electron production processes.

  9. Incidence and Pattern of Graft-versus-Host Disease in Patients Undergoing Allogeneic Transplantation after Nonmyeloablative Conditioning with Total Lymphoid Irradiation and Antithymocyte Globulin

    Directory of Open Access Journals (Sweden)

    Lauren Veltri

    2013-01-01

    Full Text Available Nonmyeloablative (NMA conditioning with total lymphoid irradiation and antithymocyte globulin (TLI/ATG has been shown to protect against acute graft-versus-host disease (GVHD. We report here our institutional experience with allogeneic transplantation following NMA conditioning with TLI/ATG (. GVHD prophylaxis consisted of a combination of a calcineurin inhibitor and mycophenolate mofetil. Median patient age was 59 years. The median followup of surviving patients is 545 days. One patient experienced primary graft rejection. The median time to neutrophil engraftment was 18 days and platelet engraftment was 9.5 days. The cumulative incidence (CI of grade II–IV acute GVHD at day +100 was 28.6% and 38.1% at day +180. The CI for grade III-IV acute GVHD was 28.6% at day +180. CI of chronic GVHD was 45.2% at 1 year. The CI of disease relapse was 9.5% at 1 year. The rate of nonrelapse mortality (NRM was 0% at day +100 and only 9.5% at 1 year. The overall and progression free survival at 1 year was 81% and 80.4%, respectively. Our limited, retrospective data show encouraging relapse and NRM rates with TLI/ATG-based NMA conditioning, but with higher than previously reported rates of acute and chronic GVHD, underscoring the need for novel strategies designed to effectively prevent GVHD.

  10. External audits of therapeutic photon beams in non-reference conditions. Mailed dosimetry checks with the EC multipurpose phantom

    International Nuclear Information System (INIS)

    Gomola, I.; Huyskens, D.; Dutreix, A.

    2001-01-01

    In this paper various methods for dosimetric calculation using the multipurpose solid phantom are presented. The present study indicates that the mailed multipurpose solid phantom is a useful tool to check the dose calculation of treatment planning systems, because a large number of dosimetric parameters per beam can be checked. (authors)

  11. On the threshold conditions for electron beam damage of asbestos amosite fibers in the transmission electron microscope (TEM).

    Science.gov (United States)

    Martin, Joannie; Beauparlant, Martin; Sauvé, Sébastien; L'Espérance, Gilles

    2016-12-01

    Asbestos amosite fibers were investigated to evaluate the damage caused by a transmission electron microscope (TEM) electron beam. Since elemental x-ray intensity ratios obtained by energy dispersive x-ray spectroscopy (EDS) are commonly used for asbestos identification, the impact of beam damage on these ratios was evaluated. It was determined that the magnesium/silicon ratio best represented the damage caused to the fiber. Various tests showed that most fibers have a current density threshold above which the chemical composition of the fiber is modified. The value of this threshold current density varied depending on the fiber, regardless of fiber diameter, and in some cases could not be determined. The existence of a threshold electron dose was also demonstrated. This value was dependent on the current density used and can be increased by providing a recovery period between exposures to the electron beam. This study also established that the electron beam current is directly related to the damage rate above a current density of 165 A/cm 2 . The large number of different results obtained suggest, that in order to ensure that the amosite fibers are not damaged, analysis should be conducted below a current density of 100 A/cm 2 .

  12. A method of combining STEM image with parallel beam diffraction and electron-optical conditions for diffractive imaging

    International Nuclear Information System (INIS)

    He Haifeng; Nelson, Chris

    2007-01-01

    We describe a method of combining STEM imaging functionalities with nanoarea parallel beam electron diffraction on a modern TEM. This facilitates the search for individual particles whose diffraction patterns are needed for diffractive imaging or structural studies of nanoparticles. This also lays out a base for 3D diffraction data collection

  13. Condition assessment and methods of abatement of prestressed concrete box-beam deterioration, phase II : volume 1.

    Science.gov (United States)

    2009-04-13

    Side-by-side box-beam bridge constitutes approximately 17 percent of bridges built or replaced annually on : public roads and there is a renewed thrust to use this bridge type for rapid construction under the Highway for : LIFE program. Further, fail...

  14. Condition assessment and methods of abatement of prestressed concrete box-beam deterioration, phase II : volume 2.

    Science.gov (United States)

    2009-04-13

    Side-by-side box-beam bridge constitutes approximately 17 percent of bridges built or replaced annually on public roads and there is a renewed thrust to use this bridge type for rapid construction under the Highway for LIFE program. Further, failure ...

  15. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    CERN Document Server

    Guthoff, Moritz; Dabrowski, Anne; De Boer, Wim; Stickland, David; Lange, Wolfgang; Lohmann, Wolfgang

    2013-01-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector ef fi ciency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, becaus...

  16. Production of muon pairs in the continuum region by 39.5 GeV/c π+-, K+-, p and anti p beams incident on a copper target

    International Nuclear Information System (INIS)

    Corden, M.J.; Dowell, J.D.; Eastwood, D.; Garvey, J.; Homer, R.J.; Jobes, M.; Kenyon, I.R.; McMahon, T.J.; Vallance, R.J.; Watkins, P.M.; Wilson, J.A.; Gago, J.; Jung, M.; Sonderegger, P.; Treille, D.; Woodworth, P.L.; Eckardt, V.; Fent, J.; Pretzl, K.; Seyboth, P.; Seyerlein, J.; Perrin, D.; Sumorok, K.C.T.O.

    1978-01-01

    General features of the inclusive hadroproduction of muon pairs of mass greater than 1.5 GeV/c 2 are shown. For incident π - , the data extend up to M = 5.7 GeV/c 2 (i.e. M 2 /s approximately 0.4). The scaling cross section M 3 dsigma/dM for π - N reaction is much flatter than that for pN reactions and exceeds the latter by two to three orders of magnitude at large M 2 /s. (Auth.)

  17. Estimation of fracture conditions of ceramics by thermal shock with laser beams based on the maximum compressive stress criterion

    International Nuclear Information System (INIS)

    Akiyama, Shigeru; Amada, Shigeyasu.

    1992-01-01

    Structural ceramics are attracting attention in the development of space planes, aircraft and nuclear fusion reactors because they have excellent wear-resistant and heat-resistant characteristics. However, in some applications it is anticipated that they will be exposed to very-high-temperature environments of the order of thousands of degrees. Therefore, it is very important to investigate their thermal shock characteristics. In this report, the distributions of temperatures and thermal stresses of cylindrically shaped ceramics under irradiation by laser beams are discussed using the finite-element computer code (MARC) with arbitrary quadrilateral axisymmetric ring elements. The relationships between spot diameters of laser beams and maximum values of compressive thermal stresses are derived for various power densities. From these relationships, a critical fracture curve is obtained, and it is compared with the experimental results. (author)

  18. A program for monitor unit calculation for high energy photon beams in isocentric condition based on measured data

    International Nuclear Information System (INIS)

    Gesheva-Atanasova, N.

    2008-01-01

    The aim of this study is: 1) to propose a procedure and a program for monitor unit calculation for radiation therapy with high energy photon beams, based on data measured by author; 2) to compare this data with published one and 3) to evaluate the precision of the monitor unit calculation program. From this study it could be concluded that, we reproduced with a good agreement the published data, except the TPR values for dept up to 5 cm. The measured relative weight of upper and lower jaws - parameter A was dramatically different from the published data, but perfectly described the collimator exchange effect for our treatment machine. No difference was found between the head scatter ratios, measured in a mini phantom and those measured with a proper brass buildup cap. Our monitor unit calculation program was found to be reliable and it can be applied for check up of the patient's plans for irradiation with high energy photon beams and for some fast calculations. Because of the identity in the construction, design and characteristics of the Siemens accelerators, and the agreement with the published data for the same beam qualities, we hope that most of our experimental data and this program can be used after verification in other hospitals

  19. Fungos associados às sementes (Cariopses de cana-de-açúcar: métodos para detecção, incidência e relação entre incidência fúngica e ambiente de produção das sementes Sugarcane seedborne (Caryopses fungi: detection methods, incidence and relation between fungical incidence and seed production conditions

    Directory of Open Access Journals (Sweden)

    Thais Dias Martins

    2009-09-01

    freqüentemente encontrados foram: Bipolaris sacchari; Bipolaris spp.; Cladosporium spp.; Curvularia spp.; Fusarium verticillioides; Fusarium semitectum e Phoma herbarum. Quando se comparou a porcentagem de incidência dos diversos fungos com o ambiente de produção das sementes, observou-se que não houve relação de temperatura e umidade relativa com incidência fúngica. Supõe-se que as variações de incidência possam estar relacionadas com diferentes fontes de inóculo nos locais de cruzamento ou características genéticas das sementes.This study had as objectives: to determine the most adequate method for detection and identification of sugarcane seedborne fungi; to characterize the associated fungi; to verify the incidences and to relate the fungical incidence in these seeds with the conditions where they were produced. To know the most adequate method of detection, two substrates were compared in Petri dishes: filter paper on agar-water culture medium and only filter paper. Glass and plastic Petri plates were utilized, to verify the recipient influence. It was also compared two light regimens (12h alternating cycles of light and darkness and continuous darkness. The seeds were kept during seven days under constant temperature of 28 ± 2ºC, when the evaluations were proceeded. The requirements for comparison of the methods were sensitivity, economicity and practicity. After the determination of the most adequate method, were done health tests of 29 crosses of the years 2002, 2003 and 2004, to characterize the seedborne fungi and verify their incidences. Later, these incidences were compared to the conditions of temperature and relative humidity from where the seeds were produced at the breeding program. The method considered most appropriated, in agreement with the analyzed parameters, was the filter paper in plastic Petri plate and the incubation under light regimen (12h alternating cycles of light and darkness. The detected fungi were: Alternaria

  20. Modelling spatial relationship between climatic conditions and annual parasite incidence of malaria in southern part of Sistan&Balouchistan Province of Iran using spatial statistic models

    Directory of Open Access Journals (Sweden)

    Mansour Halimi

    2014-02-01

    Full Text Available Objective: To model spatial relationship between climatic conditions and annual parasite incidence (API of malaria in southern part of Sistan&Balouchistan Province of Iran using spatial statistic models . Methods: A geographical weighted regression model was applied for predicting API by 3 climatic factors in order to model the spatial API of malaria in Sistan&Baluchistan Province of Iran. Results: The results indicated that most important climatic factor for explaining API in Sistan&Baluchistan was annual rainfall being of more importance in southern part of study area such as Chabahar, and Nikshar. The temperature and relative humidity are of the second and third priority respectively. The importance of these two climatic factors is higher in northern part of the studied region. The spatial autocorrelation (Moran ’s I for standard residual of applied geographical weighted regression model is -0.022 which indicated no spatial patterns. Conclusions: This model explained only 0.51 of API spatial variation (R2=0.51. Thus, the nonclimatic factors such as socioeconomic, lifestyle and the neighborhood position of this province with Afghanistan, and Pakistan also should be considered in epidemiological survey of malaria in Sistan&Baluchistan.

  1. Experimental and Computational Study of the Flow past a Simplified Geometry of an Engine/Pylon/Wing Installation at low velocity/moderate incidence flight conditions

    Science.gov (United States)

    Bury, Yannick; Lucas, Matthieu; Bonnaud, Cyril; Joly, Laurent; ISAE Team; Airbus Team

    2014-11-01

    We study numerically and experimentally the vortices that develop past a model geometry of a wing equipped with pylon-mounted engine at low speed/moderate incidence flight conditions. For such configuration, the presence of the powerplant installation under the wing initiates a complex, unsteady vortical flow field at the nacelle/pylon/wing junctions. Its interaction with the upper wing boundary layer causes a drop of aircraft performances. In order to decipher the underlying physics, this study is initially conducted on a simplified geometry at a Reynolds number of 200000, based on the chord wing and on the freestream velocity. Two configurations of angle of attack and side-slip angle are investigated. This work relies on unsteady Reynolds Averaged Navier Stokes computations, oil flow visualizations and stereoscopic Particle Image Velocimetry measurements. The vortex dynamics thus produced is described in terms of vortex core position, intensity, size and turbulent intensity thanks to a vortex tracking approach. In addition, the analysis of the velocity flow fields obtained from PIV highlights the influence of the longitudinal vortex initiated at the pylon/wing junction on the separation process of the boundary layer near the upper wing leading-edge.

  2. Step-flow anisotropy of the m-plane GaN (1100) grown under nitrogen-rich conditions by plasma-assisted molecular beam epitaxy

    International Nuclear Information System (INIS)

    Sawicka, Marta; Siekacz, Marcin; Skierbiszewski, Czeslaw; Turski, Henryk; Krysko, Marcin; DziePcielewski, Igor; Grzegory, Izabella; Smalc-Koziorowska, Julita

    2011-01-01

    The homoepitaxial growth of m-plane (1100) GaN was investigated by plasma-assisted molecular beam epitaxy under nitrogen-rich conditions. The surface morphologies as a function of sample miscut were studied, providing evidence for a strong growth anisotropy that is a consequence of the anisotropy of Ga adatom diffusion barriers on the m-plane surface recently calculated ab initio[Lymperakis and Neugebauer, Phys. Rev. B 79, 241308(R) (2009)]. We found that substrate miscut toward [0001] implies a step flow toward while substrate miscut toward [0001] causes formation of atomic steps either perpendicular or parallel to the [0001] direction, under N-rich conditions at 730 deg C. We describe the growth conditions for achieving atomically flat m-plane GaN layers with parallel atomic steps.

  3. Backscatter spectra measurements of the two beams on the same cone on Shenguang-III laser facility

    Science.gov (United States)

    Zha, Weiyi; Yang, Dong; Xu, Tao; Liu, Yonggang; Wang, Feng; Peng, Xiaoshi; Li, Yulong; Wei, Huiyue; Liu, Xiangming; Mei, Yu; Yan, Yadong; He, Junhua; Li, Zhichao; Li, Sanwei; Jiang, Xiaohua; Guo, Liang; Xie, Xufei; Pan, Kaiqiang; Liu, Shenye; Jiang, Shaoen; Zhang, Baohan; Ding, Yongkun

    2018-01-01

    In laser driven hohlraums, laser beams on the same incident cone may have different beam and plasma conditions, causing beam-to-beam backscatter difference and subsequent azimuthal variations in the x-ray drive on the capsule. To elucidate the large variation of backscatter proportion from beam to beam in some gas-filled hohlraum shots on Shenguang-III, two 28.5° beams have been measured with the Stimulated Raman Scattering (SRS) time-resolved spectra. A bifurcated fiber is used to sample two beams and then coupled to a spectrometer and streak camera combination to reduce the cost. The SRS spectra, characterized by a broad wavelength, were further corrected considering the temporal distortion and intensity modulation caused by components along the light path. This measurement will improve the understanding of the beam propagation inside the hohlraum and related laser plasma instabilities.

  4. Effects of temperature, packaging and electron beam irradiation processing conditions on the property behaviour of Poly (ether-block-amide) blends

    International Nuclear Information System (INIS)

    Murray, Kieran A.; Kennedy, James E.; McEvoy, Brian; Vrain, Olivier; Ryan, Damien; Cowman, Richard; Higginbotham, Clement L.

    2014-01-01

    The radiation stability of Poly (ether-block-amide) (PEBA) blended with a multifunctional phenolic antioxidant and a hindered amide light stabiliser was examined under various temperatures, packaging and electron beam processing conditions. FTIR revealed that there were slight alterations to the PEBA before irradiation; however, these became more pronounced following irradiation. The effect of varying the temperature, packaging and processing conditions on the resultant PEBA properties was apparent. For example, rheology demonstrated that the structural properties could be enhanced by manipulating the aforementioned criteria. Mechanical testing exhibited less radiation resistance when the PEBA samples were vacuum packed and exposed to irradiation. MFI and AFM confirmed that the melting strength and surface topography could be reduced/increased depending on the conditions employed. From this study it was concluded that virgin PEBA submerged in dry ice with non-vacuum packaging during the irradiation process, provided excellent radiation resistance (20.9% improvement) in contrast to the traditional method. - Highlights: • PEBA was melt blended with Irganox 565 and Tinuvin 783. • All virgin and blended PEBA samples were exposed to electron beam irradiation. • Virgin and blended PEBA was exposed to different temperatures during irradiation. • Non-vacuum and vacuum packed PEBA samples were compared following irradiation. • Virgin PEBA with non-vacuum packaging in dry ice improved the radiation resistance

  5. Effects of temperature, packaging and electron beam irradiation processing conditions on the property behaviour of Poly (ether-block-amide) blends

    Energy Technology Data Exchange (ETDEWEB)

    Murray, Kieran A., E-mail: kmurray@research.ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Road, Athlone, Co. Westmeath (Ireland); Kennedy, James E., E-mail: jkennedy@ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Road, Athlone, Co. Westmeath (Ireland); McEvoy, Brian, E-mail: Brian.Mcevoy@synergyhealthplc.com [Synergy Health, IDA Business and Technology Park, Sragh, Tullamore, Co. Offaly (Ireland); Vrain, Olivier, E-mail: Olivier.Vrain@synergyhealthplc.com [Synergy Health, IDA Business and Technology Park, Sragh, Tullamore, Co. Offaly (Ireland); Ryan, Damien, E-mail: Damien.Ryan@synergyhealthplc.com [Synergy Health, IDA Business and Technology Park, Sragh, Tullamore, Co. Offaly (Ireland); Cowman, Richard, E-mail: Richard.Cowman@synergyhealthplc.com [Synergy Health, IDA Business and Technology Park, Sragh, Tullamore, Co. Offaly (Ireland); Higginbotham, Clement L., E-mail: chigginbotham@ait.ie [Materials Research Institute, Athlone Institute of Technology, Dublin Road, Athlone, Co. Westmeath (Ireland)

    2014-06-01

    The radiation stability of Poly (ether-block-amide) (PEBA) blended with a multifunctional phenolic antioxidant and a hindered amide light stabiliser was examined under various temperatures, packaging and electron beam processing conditions. FTIR revealed that there were slight alterations to the PEBA before irradiation; however, these became more pronounced following irradiation. The effect of varying the temperature, packaging and processing conditions on the resultant PEBA properties was apparent. For example, rheology demonstrated that the structural properties could be enhanced by manipulating the aforementioned criteria. Mechanical testing exhibited less radiation resistance when the PEBA samples were vacuum packed and exposed to irradiation. MFI and AFM confirmed that the melting strength and surface topography could be reduced/increased depending on the conditions employed. From this study it was concluded that virgin PEBA submerged in dry ice with non-vacuum packaging during the irradiation process, provided excellent radiation resistance (20.9% improvement) in contrast to the traditional method. - Highlights: • PEBA was melt blended with Irganox 565 and Tinuvin 783. • All virgin and blended PEBA samples were exposed to electron beam irradiation. • Virgin and blended PEBA was exposed to different temperatures during irradiation. • Non-vacuum and vacuum packed PEBA samples were compared following irradiation. • Virgin PEBA with non-vacuum packaging in dry ice improved the radiation resistance.

  6. Analyser of sweeping electron beam

    International Nuclear Information System (INIS)

    Strasser, A.

    1993-01-01

    The electron beam analyser has an array of conductors that can be positioned in the field of the sweeping beam, an electronic signal treatment system for the analysis of the signals generated in the conductors by the incident electrons and a display for the different characteristics of the electron beam

  7. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    Science.gov (United States)

    Guthoff, Moritz; Afanaciev, Konstantin; Dabrowski, Anne; de Boer, Wim; Lange, Wolfgang; Lohmann, Wolfgang; Stickland, David

    2013-12-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector efficiency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, because of the high number of low energy neutrons in these regions. The signal decrease was stronger than expected from the number of simulated defects. Here polarization from trapped charge carriers in the defects is a likely candidate for explaining the difference, as suggested by Transient Current Technique (TCT) measurements. A single-crystalline (sCVD) diamond sensor shows a faster relative signal decrease than a pCVD sensor mounted at the same location. This is expected, since the relative increase in the number of defects is larger in sCVD than in pCVD sensors.

  8. Analysis of the incidence of postintubation injuries in patients intubated in the prehospital or early hospital conditions of the hospital emergency department and the intensive care unit

    Directory of Open Access Journals (Sweden)

    Cierniak M

    2015-10-01

    Full Text Available Marcin Cierniak,1 Dariusz Timler,1 Renata Sobczak,1 Andrzej Wieczorek,2 Przemyslaw Sekalski,3 Natalia Borkowska,2 Tomasz Gaszynski1 1Department of Emergency Medicine and Disaster Medicine, Barlicki University Hospital, 2Department of Anesthesiology and Intensive Therapy, Medical University of Lodz, 3Department of Microelectronics and Computer Science, IT Centre, Lodz University of Technology, Lodz, Poland Background: Intubation is still one of the best methods to secure the airway. In the case of prehospital or early hospital conditions when factors such as urgency, stress, or inaccuracy of the undertaken activities are involved, the risk of causing complications, for instance, edema or postintubation injuries, increases, especially while dealing with a difficult intubation. The risk of improper inflation of the endotracheal tube cuff also increases, which is considered in this study.Objective: The aim of this study was to evaluate the prevalence of postintubation complications, such as postintubation injuries or edema, in a research sample, and to examine whether such complications occur more often, for example, while using a guidewire. In this study, we also evaluated the injuries associated with the inflation of the endotracheal tube cuff.Materials and methods: This study was performed on a group of 153 patients intubated in prehospital conditions. The tests were carried out in three clinical sites that received patients from prehospital care. Postintubation injuries were revealed and photographed using videolaryngoscope, such as the C-MAC and the McGrath series 5. The endotracheal tube cuff pressure was measured using a pressure gage manual (VBM Medizintechnik GmbH. The quantitative analyses of differences between incidence of variables were assessed using χ2 test for P<0.05. Analyses have been carried out using the Statistica software.Results: In the group of 153 patients, postintubation injuries occurred in 17% of cases. The dependency

  9. X-ray and pressure conditions on the first wall of a particle beam inertial confinement reactor

    International Nuclear Information System (INIS)

    Magelssen, G.R.

    1979-01-01

    Because of the presence of a chamber gas in a particle beam reactor cavity, nonneutron target debris created from thermonuclear burn will be modified or stopped before it reaches the first reactor wall. The resulting modified spectra and pulse lengths of the debris need to be calculated to determine first wall effects. Further, the cavity overpressure created by the momentum and energy exchange between the debris and gas must also be calculated to determine its effect. The purpose of this paper is to present results of the debris-background gas problem obtained with a one fluid, two temperature plasma hydrodynamic computer code model which includes multifrequency radiation transport. Spherical symmetry, ideal gas equation of state, and LTE for each radiation frequency group were assumed. The transport of debris ions was not included and all the debris energy was assumed to be in radiation. The calculated x-ray spectra and pulse lengths and the background overpressure are presented

  10. Effects of oxygen gas flow rate and ion beam plasma conditions on the opto-electronic properties of indium molybdenum oxide films fabricated by ion beam-assisted evaporation

    International Nuclear Information System (INIS)

    Kuo, C.C.; Liu, C.C.; Lin, C.C.; Liou, Y.Y.; He, J.L.; Chen, F.S.

    2008-01-01

    The purpose of the present work is to experimentally study the effects of the oxygen gas flow rate and ion beam plasma conditions on the properties of indium molybdenum oxide (IMO) films deposited onto the polyethersulfone (PES) substrate. Crystal structure, surface morphology, and optoelectronic properties of IMO films are examined as a function of oxygen gas flow rate and ion beam discharge voltage. Experimental results show that the IMO films consist of a cubic bixbyite B-In 2 O 3 single phase with its crystal preferred orientation alone B(222). Mo 6+ ions are therefore considered to partially substitute In 3+ sites in the deposit. Under-controlled ion bombardment during deposition enhances the reaction among those arriving oxygen and metal ion species to condense into IMO film and facilitates a decreased surface roughness of IMO film. The film with ultimate crystallinity and the lowest surface roughness is obtained when the oxygen flow rate of 3 sccm and the discharge voltage of 110 V are employed. This results in the lowest electrical resistivity due mainly to the increased Hall mobility and irrelevant to carrier concentration. The lowest electrical resistivity of 8.63 x 10 -4 ohm-cm with a 84.63% transmittance at a wavelength of 550 nm can be obtained, which satisfies the requirement of a flexible transparent conductive polymer substrate

  11. Impact of growth and annealing conditions on the parameters of Ge/Si(001) relaxed layers grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Yurasov, D. V., E-mail: Inquisitor@ipm.sci-nnov.ru [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Bobrov, A. I. [Lobachevsky State University of Nizhny Novgorod (Russian Federation); Daniltsev, V. M.; Novikov, A. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Pavlov, D. A. [Lobachevsky State University of Nizhny Novgorod (Russian Federation); Skorokhodov, E. V.; Shaleev, M. V.; Yunin, P. A. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

    2015-11-15

    Influence of the Ge layer thickness and annealing conditions on the parameters of relaxed Ge/Si(001) layers grown by molecular beam epitaxy via two-stage growth is investigated. The dependences of the threading dislocation density and surface roughness on the Ge layer thickness, annealing temperature and time, and the presence of a hydrogen atmosphere are obtained. As a result of optimization of the growth and annealing conditions, relaxed Ge/Si(001) layers which are thinner than 1 μm with a low threading dislocation density on the order of 10{sup 7} cm{sup –2} and a root mean square roughness of less than 1 nm are obtained.

  12. Wheelchair incidents

    NARCIS (Netherlands)

    Drongelen AW van; Roszek B; Hilbers-Modderman ESM; Kallewaard M; Wassenaar C; LGM

    2002-01-01

    This RIVM study was performed to gain insight into wheelchair-related incidents with powered and manual wheelchairs reported to the USA FDA, the British MDA and the Dutch Center for Quality and Usability Research of Technical Aids (KBOH). The data in the databases do not indicate that incidents with

  13. Effective beam method for element concentrations

    International Nuclear Information System (INIS)

    Tolhurst, Thomas; Barbi, Mauricio; Tokaryk, Tim

    2015-01-01

    A method to evaluate chemical element concentrations in samples by generating an effective polychromatic beam using as initial input real monochromatic beam data is presented. There is a great diversity of research being conducted at synchrotron facilities around the world and a diverse set of beamlines to accommodate this research. Time is a precious commodity at synchrotron facilities; therefore, methods that can maximize the time spent collecting data are of value. At the same time the incident radiation spectrum, necessary for some research, may not be known on a given beamline. A preliminary presentation of a method applicable to X-ray fluorescence spectrocopic analyses that overcomes the lack of information about the incident beam spectrum that addresses both of these concerns is given here. The method is equally applicable for other X-ray sources so long as local conditions are considered. It relies on replacing the polychromatic spectrum in a standard fundamental parameters analysis with a set of effective monochromatic photon beams. A beam is associated with each element and can be described by an analytical function allowing extension to elements not included in the necessary calibration measurement(s)

  14. Anatomy-based inverse optimization in high-dose-rate brachytherapy combined with hypofractionated external beam radiotherapy for localized prostate cancer: Comparison of incidence of acute genitourinary toxicity between anatomy-based inverse optimization and geometric optimization

    International Nuclear Information System (INIS)

    Akimoto, Tetsuo; Katoh, Hiroyuki; Kitamoto, Yoshizumi; Shirai, Katsuyuki; Shioya, Mariko; Nakano, Takashi

    2006-01-01

    Purpose: To evaluate the advantages of anatomy-based inverse optimization (IO) in planning high-dose-rate (HDR) brachytherapy. Methods and Materials: A total of 114 patients who received HDR brachytherapy (9 Gy in two fractions) combined with hypofractionated external beam radiotherapy (EBRT) were analyzed. The dose distributions of HDR brachytherapy were optimized using geometric optimization (GO) in 70 patients and by anatomy-based IO in the remaining 44 patients. The correlation between the dose-volume histogram parameters, including the urethral dose and the incidence of acute genitourinary (GU) toxicity, was evaluated. Results: The averaged values of the percentage of volume receiving 80-150% of the prescribed minimal peripheral dose (V 8 -V 15 ) of the urethra generated by anatomy-based IO were significantly lower than the corresponding values generated by GO. Similarly, the averaged values of the minimal dose received by 5-50% of the target volume (D 5 -D 5 ) obtained using anatomy-based IO were significantly lower than those obtained using GO. Regarding acute toxicity, Grade 2 or worse acute GU toxicity developed in 23% of all patients, but was significantly lower in patients for whom anatomy-based IO (16%) was used than in those for whom GO was used (37%), consistent with the reduced urethral dose (p <0.01). Conclusion: The results of this study suggest that anatomy-based IO is superior to GO for dose optimization in HDR brachytherapy for prostate cancer

  15. Non-equilibrium surface conditions and microstructural changes following pulsed laser irradiation and ion beam mixing of Ni overlayers on sintered alpha-SiC

    International Nuclear Information System (INIS)

    More, K.L.; Davis, R.F.

    1986-01-01

    Pulsed laser irradiation and ion beam mixing of thin Ni overlayers on sintered alpha-SiC have been investigated as potential surface modification techniques for the enhancement of the mechanical properties of the SiC. Each of these surface processing methods are nonequilibrium techniques; materials interactions can be induced at the specimen surface which are not possible with conventional thermal techniques. As a result of the surface modification, the physical properties of the ceramic can be altered under the correct processing conditions. Following laser irradiation using a pulsed ruby or krypton fluoride (KrF) excimer laser, the fracture strength of the SiC was increased by approximately 50 percent and 20 percent, respectively. However, ion-beam mixing of Ni on SiC resulted in no change in fracture strength. Cross-sectional transmission electron microscopy, scanning electron microscopy, secondary ion mass spectroscopy, and Rutherford backscattering techniques, have been used to characterize the extent of mixing between the Ni and SiC as a result of the surface modification and to determine the reason(s) for the observed changes in fracture strength. 19 references

  16. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Guthoff, Moritz, E-mail: moritz.guthoff@cern.ch [CERN, 1211 Genève 23 (Switzerland); Institut für Experimentelle Kernphysik, Karlsruhe Institute of Technology, Campus Süd, P.O. Box 6980, 76128 Karlsruhe (Germany); Afanaciev, Konstantin [DESY, Platanenallee 6, 15738 Zeuthen (Germany); NC PHEP BSU, Minsk (Belarus); Dabrowski, Anne [CERN, 1211 Genève 23 (Switzerland); Boer, Wim de [Institut für Experimentelle Kernphysik, Karlsruhe Institute of Technology, Campus Süd, P.O. Box 6980, 76128 Karlsruhe (Germany); Lange, Wolfgang [DESY, Platanenallee 6, 15738 Zeuthen (Germany); Lohmann, Wolfgang [DESY, Platanenallee 6, 15738 Zeuthen (Germany); Brandenburgische Technische Universität, Postfach 101344, 03013 Cottbus (Germany); Stickland, David [Princeton University, Princeton, NJ 08544-0708 (United States)

    2013-12-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector efficiency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, because of the high number of low energy neutrons in these regions. The signal decrease was stronger than expected from the number of simulated defects. Here polarization from trapped charge carriers in the defects is a likely candidate for explaining the difference, as suggested by Transient Current Technique (TCT) measurements. A single-crystalline (sCVD) diamond sensor shows a faster relative signal decrease than a pCVD sensor mounted at the same location. This is expected, since the relative increase in the number of defects is larger in sCVD than in pCVD sensors. -- Highlights: •The BCM system and its diamond detectors at the CMS experiment of the LHC are presented. •Detectors show a decreased signal strength with increasing integrated luminosity. •CCD measurements using constant HV and alternating HV to prevent polarization are compared. •TCT measurements show a decreasing signal when polarization builds up. •Polarization effects are a likely

  17. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    International Nuclear Information System (INIS)

    Guthoff, Moritz; Afanaciev, Konstantin; Dabrowski, Anne; Boer, Wim de; Lange, Wolfgang; Lohmann, Wolfgang; Stickland, David

    2013-01-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector efficiency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, because of the high number of low energy neutrons in these regions. The signal decrease was stronger than expected from the number of simulated defects. Here polarization from trapped charge carriers in the defects is a likely candidate for explaining the difference, as suggested by Transient Current Technique (TCT) measurements. A single-crystalline (sCVD) diamond sensor shows a faster relative signal decrease than a pCVD sensor mounted at the same location. This is expected, since the relative increase in the number of defects is larger in sCVD than in pCVD sensors. -- Highlights: •The BCM system and its diamond detectors at the CMS experiment of the LHC are presented. •Detectors show a decreased signal strength with increasing integrated luminosity. •CCD measurements using constant HV and alternating HV to prevent polarization are compared. •TCT measurements show a decreasing signal when polarization builds up. •Polarization effects are a likely

  18. Controlling Second Harmonic Efficiency of Laser Beam Interactions

    Science.gov (United States)

    Barnes, Norman P. (Inventor); Walsh, Brian M. (Inventor); Reichle, Donald J. (Inventor)

    2011-01-01

    A method is provided for controlling second harmonic efficiency of laser beam interactions. A laser system generates two laser beams (e.g., a laser beam with two polarizations) for incidence on a nonlinear crystal having a preferred direction of propagation. Prior to incidence on the crystal, the beams are optically processed based on the crystal's beam separation characteristics to thereby control a position in the crystal along the preferred direction of propagation at which the beams interact.

  19. Geometrical conditions at the quantitative neutronographic texture analysis

    International Nuclear Information System (INIS)

    Tobisch, J.; Kleinstueck, K.

    1975-10-01

    The beam geometry for measuring quantitative pole figures by a neutronographic texture diffractometer is explained for transmission and reflection arrangement of spherical samples and sheets. For given dimensions of counter aperture the maximum possible cross sections of the incident beam are calculated as a function of sample dimensions and the Bragg angle theta. Methods for the calculation of absorption factors and volume correction are given. Under special conditions advantages result in the transmission case for sample motion into the direction +α. (author)

  20. Effects of temperature, packaging and electron beam irradiation processing conditions on the property behaviour of Poly (ether-block-amide) blends.

    Science.gov (United States)

    Murray, Kieran A; Kennedy, James E; McEvoy, Brian; Vrain, Olivier; Ryan, Damien; Cowman, Richard; Higginbotham, Clement L

    2014-06-01

    The radiation stability of Poly (ether-block-amide) (PEBA) blended with a multifunctional phenolic antioxidant and a hindered amide light stabiliser was examined under various temperatures, packaging and electron beam processing conditions. FTIR revealed that there were slight alterations to the PEBA before irradiation; however, these became more pronounced following irradiation. The effect of varying the temperature, packaging and processing conditions on the resultant PEBA properties was apparent. For example, rheology demonstrated that the structural properties could be enhanced by manipulating the aforementioned criteria. Mechanical testing exhibited less radiation resistance when the PEBA samples were vacuum packed and exposed to irradiation. MFI and AFM confirmed that the melting strength and surface topography could be reduced/increased depending on the conditions employed. From this study it was concluded that virgin PEBA submerged in dry ice with non-vacuum packaging during the irradiation process, provided excellent radiation resistance (20.9% improvement) in contrast to the traditional method. Copyright © 2014. Published by Elsevier B.V.

  1. Performance evaluation of a drag-disc turbine transducer and three-beam gamma densitometer under transient two-phase flow conditions

    International Nuclear Information System (INIS)

    Nalezny, C.L.; Chen, L.L.; Solbrig, C.W.

    1979-01-01

    One of the primary variables measured in the Loss-of-Fluid Test (LOFT) Program is mass flow rate. LOFT uses drag-disc turbine tranducers (DTT) and a three-beam gamma densitometer to measure parameters from which mass flow may be computed. The transducer combination was performance tested under transient conditions in the blowdown loop at the LOFT Test Support Facility (LTSF). The performance tests consisted of three partial blowdowns of different durations starting from the same initial conditions. The reference mean mass flow rate was determined by measuring the amount of water required to reestablish initial conditions after each partial blowdown. The average mass flow rates computed from the output of the drag disc, turbine, and gamma densitometer were compared to the reference mean mass flow rates over three blowdown intervals. The tests indicated that the equal phase velocity mass measurement model provided excellent results through the use of the turbine and densitometer, and drag disc and densitometer when the phase velocities were nearly equal

  2. Incidents analysis

    International Nuclear Information System (INIS)

    Francois, P.

    1996-01-01

    We undertook a study programme at the end of 1991. To start with, we performed some exploratory studies aimed at learning some preliminary lessons on this type of analysis: Assessment of the interest of probabilistic incident analysis; possibility of using PSA scenarios; skills and resources required. At the same time, EPN created a working group whose assignment was to define a new approach for analysis of incidents on NPPs. This working group gave thought to both aspects of Operating Feedback that EPN wished to improve: Analysis of significant incidents; analysis of potential consequences. We took part in the work of this group, and for the second aspects, we proposed a method based on an adaptation of the event-tree method in order to establish a link between existing PSA models and actual incidents. Since PSA provides an exhaustive database of accident scenarios applicable to the two most common types of units in France, they are obviously of interest for this sort of analysis. With this method we performed some incident analyses, and at the same time explores some methods employed abroad, particularly ASP (Accident Sequence Precursor, a method used by the NRC). Early in 1994 EDF began a systematic analysis programme. The first, transient phase will set up methods and an organizational structure. 7 figs

  3. Incidents analysis

    Energy Technology Data Exchange (ETDEWEB)

    Francois, P

    1997-12-31

    We undertook a study programme at the end of 1991. To start with, we performed some exploratory studies aimed at learning some preliminary lessons on this type of analysis: Assessment of the interest of probabilistic incident analysis; possibility of using PSA scenarios; skills and resources required. At the same time, EPN created a working group whose assignment was to define a new approach for analysis of incidents on NPPs. This working group gave thought to both aspects of Operating Feedback that EPN wished to improve: Analysis of significant incidents; analysis of potential consequences. We took part in the work of this group, and for the second aspects, we proposed a method based on an adaptation of the event-tree method in order to establish a link between existing PSA models and actual incidents. Since PSA provides an exhaustive database of accident scenarios applicable to the two most common types of units in France, they are obviously of interest for this sort of analysis. With this method we performed some incident analyses, and at the same time explores some methods employed abroad, particularly ASP (Accident Sequence Precursor, a method used by the NRC). Early in 1994 EDF began a systematic analysis programme. The first, transient phase will set up methods and an organizational structure. 7 figs.

  4. Is environmental radon gas associated with the incidence of neurodegenerative conditions? A retrospective study of multiple sclerosis in radon affected areas in England and Wales

    International Nuclear Information System (INIS)

    Groves-Kirkby, Christopher J.; Denman, Antony R.; Campbell, Jackie; Crockett, Robin G.M.; Phillips, Paul S.; Rogers, Stephen

    2016-01-01

    To test whether an association exists between radon gas concentration in the home and increased multiple sclerosis (MS) incidence, a retrospective study was undertaken of MS incidence in known areas of raised domestic radon concentration in England and Wales, using The Health Improvement Network (THIN) clinical research database. The study population comprised 20,140,498 person-years of clinical monitoring (males: 10,056,628: 49.93%; females: 10,083,870: 50.07%), representing a mean annual population of 2.5 million individuals. To allow for the possible latency of MS initiation following exposure, data extraction was limited to patients with at least five years registration history with the same GP practice before first diagnosis. Patient records were allocated to one of nine radon concentration bands depending on the average radon level in their postcode sector. MS incidence was analysed by searching for patients with first MS diagnosis over the eight calendar years 2005–2012 inclusive. 1512 new MS cases were diagnosed, 1070 females, 442 males, equivalent to raw incidence rates of 7.51, 10.61 and 4.40 per 10 5 person-years respectively, comparable to previously reported results. Of these new cases, 115 could be allocated to one of the radon bands representing high radon areas. Standardising to the UK 2010 population, excess relative risk (ERR) figures for MS were calculated for each radon band. Linear regression of ERR against mean band radon concentration shows a positive gradient of 0.22 per 100 Bq·m −3 (R 2  = 0.25, p = 0.0961) when forced through the origin to represent a linear-no-threshold response. The null hypothesis falls inside the 95% confidence interval for the linear fit and therefore this fit is not statistically significant. We conclude that, despite THIN sampling around 5% of the population, insufficient data was available to confirm or refute the hypothesised association between MS incidence and radon concentration. - Highlights:

  5. Beam-beam phenomenology

    International Nuclear Information System (INIS)

    Teng, L.C.

    1980-01-01

    In colliding beam storage rings the beam collision regions are generally so short that the beam-beam interaction can be considered as a series of evenly spaced non-linear kicks superimposed on otherwise stable linear oscillations. Most of the numerical studies on computers were carried out in just this manner. But for some reason this model has not been extensively employed in analytical studies. This is perhaps because all analytical work has so far been done by mathematicians pursuing general transcendental features of non-linear mechanics for whom this specific model of the specific system of colliding beams is too parochial and too repugnantly physical. Be that as it may, this model is of direct interest to accelerator physicists and is amenable to (1) further simplification, (2) physical approximation, and (3) solution by analogy to known phenomena

  6. Experimental study on vortex-induced motions of a semi-submersible with square columns and pontoons at different draft conditions and current incidences

    Directory of Open Access Journals (Sweden)

    Mingyue Liu

    2017-05-01

    Full Text Available The Vortex-induced Motions (VIM phenomenon of semi-submersibles is relevant for the fatigue life of moorings and risers. Model tests regarding the VIM behavior of a semi-submersible with four square columns were conducted in order to investigate the effects of the current incidence and the aspect ratio of the immerged column. The experimental results show that the largest transverse amplitudes are around 70% of the column width at 30° and 45° incidences in a range of reduced velocities from 5 to 8 when the aspect ratio of the immerged column is 1.90. The largest yaw motion occurs at 0° incidence with the peak value around 4.5°. Similar characteristics of the VIM response are observed for the semi-submersible with aspect ratios of 1.90 and 1.73. When the aspect ratio decreases 50% to 0.87, 30% decrease in the peak transverse amplitudes can be seen.

  7. Antimicrobial drug use and risk factors associated with treatment incidence and mortality in Swiss veal calves reared under improved welfare conditions.

    Science.gov (United States)

    Lava, M; Schüpbach-Regula, G; Steiner, A; Meylan, M

    2016-04-01

    Ninety-one Swiss veal farms producing under a label with improved welfare standards were visited between August and December 2014 to investigate risk factors related to antimicrobial drug use and mortality. All herds consisted of own and purchased calves, with a median of 77.4% of purchased calves. The calves' mean age was 29±15days at purchasing and the fattening period lasted at average 120±28 days. The mean carcass weight was 125±12kg. A mean of 58±33 calves were fattened per farm and year, and purchased calves were bought from a mean of 20±17 farms of origin. Antimicrobial drug treatment incidence was calculated with the defined daily dose methodology. The mean treatment incidence (TIADD) was 21±15 daily doses per calf and year. The mean mortality risk was 4.1%, calves died at a mean age of 94±50 days, and the main causes of death were bovine respiratory disease (BRD, 50%) and gastro-intestinal disease (33%). Two multivariable models were constructed, for antimicrobial drug treatment incidence (53 farms) and mortality (91 farms). No quarantine, shared air space for several groups of calves, and no clinical examination upon arrival at the farm were associated with increased antimicrobial treatment incidence. Maximum group size and weight differences >100kg within a group were associated with increased mortality risk, while vaccination and beef breed were associated with decreased mortality risk. The majority of antimicrobial treatments (84.6%) were given as group treatments with oral powder fed through an automatic milk feeding system. Combination products containing chlortetracycline with tylosin and sulfadimidine or with spiramycin were used for 54.9%, and amoxicillin for 43.7% of the oral group treatments. The main indication for individual treatment was BRD (73%). The mean age at the time of treatment was 51 days, corresponding to an estimated weight of 80-100kg. Individual treatments were mainly applied through injections (88.5%), and included

  8. The Influence of As-Built Surface Conditions on Mechanical Properties of Ti-6Al-4V Additively Manufactured by Selective Electron Beam Melting

    Science.gov (United States)

    Sun, Y. Y.; Gulizia, S.; Oh, C. H.; Fraser, D.; Leary, M.; Yang, Y. F.; Qian, M.

    2016-03-01

    Achieving a high surface finish is a major challenge for most current metal additive manufacturing processes. We report the first quantitative study of the influence of as-built surface conditions on the tensile properties of Ti-6Al-4V produced by selective electron beam melting (SEBM) in order to better understand the SEBM process. Tensile ductility was doubled along with noticeable improvements in tensile strengths after surface modification of the SEBM-fabricated Ti-6Al-4V by chemical etching. The fracture surfaces of tensile specimens with different surface conditions were characterised and correlated with the tensile properties obtained. The removal of a 650- μm-thick surface layer by chemical etching was shown to be necessary to eliminate the detrimental influence of surface defects on mechanical properties. The experimental results and analyses underline the necessity to modify the surfaces of SEBM-fabricated components for structural applications, particularly for those components which contain complex internal concave and convex surfaces and channels.

  9. Wire Scanner Beam Profile Measurements: LANSCE Facility Beam Development

    International Nuclear Information System (INIS)

    Gilpatrick, John D.; Batygin, Yuri K.; Gonzales, Fermin; Gruchalla, Michael E.; Kutac, Vincent G.; Martinez, Derwin; Sedillo, James Daniel; Pillai, Chandra; Rodriguez Esparza, Sergio; Smith, Brian G.

    2012-01-01

    The Los Alamos Neutron Science Center (LANSCE) is replacing Wire Scanner (WS) beam profile measurement systems. Three beam development tests have taken place to test the new wire scanners under beam conditions. These beam development tests have integrated the WS actuator, cable plant, electronics processors and associated software and have used H - beams of different beam energy and current conditions. In addition, the WS measurement-system beam tests verified actuator control systems for minimum profile bin repeatability and speed, checked for actuator backlash and positional stability, tested the replacement of simple broadband potentiometers with narrow band resolvers, and tested resolver use with National Instruments Compact Reconfigurable Input and Output (cRIO) Virtual Instrumentation. These beam tests also have verified how trans-impedance amplifiers react with various types of beam line background noise and how noise currents were not generated. This paper will describe these beam development tests and show some resulting data.

  10. Wire Scanner Beam Profile Measurements: LANSCE Facility Beam Development

    Energy Technology Data Exchange (ETDEWEB)

    Gilpatrick, John D. [Los Alamos National Laboratory; Batygin, Yuri K. [Los Alamos National Laboratory; Gonzales, Fermin [Los Alamos National Laboratory; Gruchalla, Michael E. [Los Alamos National Laboratory; Kutac, Vincent G. [Los Alamos National Laboratory; Martinez, Derwin [Los Alamos National Laboratory; Sedillo, James Daniel [Los Alamos National Laboratory; Pillai, Chandra [Los Alamos National Laboratory; Rodriguez Esparza, Sergio [Los Alamos National Laboratory; Smith, Brian G. [Los Alamos National Laboratory

    2012-05-15

    The Los Alamos Neutron Science Center (LANSCE) is replacing Wire Scanner (WS) beam profile measurement systems. Three beam development tests have taken place to test the new wire scanners under beam conditions. These beam development tests have integrated the WS actuator, cable plant, electronics processors and associated software and have used H{sup -} beams of different beam energy and current conditions. In addition, the WS measurement-system beam tests verified actuator control systems for minimum profile bin repeatability and speed, checked for actuator backlash and positional stability, tested the replacement of simple broadband potentiometers with narrow band resolvers, and tested resolver use with National Instruments Compact Reconfigurable Input and Output (cRIO) Virtual Instrumentation. These beam tests also have verified how trans-impedance amplifiers react with various types of beam line background noise and how noise currents were not generated. This paper will describe these beam development tests and show some resulting data.

  11. Provider-initiated HIV testing & counselling in incident tuberculosis cases under National TB Programme conditions at a tertiary care teaching hospital in Tirupati, south India

    Directory of Open Access Journals (Sweden)

    Alladi Mohan

    2017-01-01

    >Interpretation & conclusions: The findings of this study showed that a higher proportion of TB patients underwent HIV testing (75% compared to the national figure of 63 per cent in 2013-2014. HIV seropositivity (4.6% in TB patients who underwent HIV testing was similar to the five per cent figure observed at national level during 2013-2014. The HIV status of 25 per cent of patients with incident TB still remained unknown, suggesting a need for better integration and co-ordination for effective management of HIV-TB co-infection.

  12. Response of Solid and Liquid Targets to High Power Proton Beams for Neutrino Factories

    CERN Document Server

    Sievers, P

    2000-01-01

    The response of solid and liquid targets to rapid heating by the incident proton beam is assessed in a classical way, among other things by solving the wave equation under linear conditions and in cylindrical symmetry. This study provides bench mark values and allows to identify critical issues and limiting factors which can help to guide further investigations with more sophisticated means.

  13. On nonlinear development of beam instability

    International Nuclear Information System (INIS)

    Popel', S.I.; Tsytovich, V.N.

    1990-01-01

    Radiation-resonance interactions are taken into account in the problem of dynamics of an electron beam inb plasma. The beam characteristics to be taken into account are determined. Stabilization conditions for beam instability are established

  14. The effect of oblique angle of sound incidence, realistic edge conditions, curvature and in-plane panel stresses on the noise reduction characteristics of general aviation type panels

    Science.gov (United States)

    Grosveld, F.; Lameris, J.; Dunn, D.

    1979-01-01

    Experiments and a theoretical analysis were conducted to predict the noise reduction of inclined and curved panels. These predictions are compared to the experimental results with reasonable agreement between theory and experiment for panels under an oblique angle of sound incidence. Theoretical as well as experimental results indicate a big increase in noise reduction when a flat test panel is curved. Further curving the panel slightly decreases the noise reduction. Riveted flat panels are shown to give a higher noise reduction in the stiffness-controlled frequency region, while bonded panels are superior in this region when the test panel is curved. Experimentally measured noise reduction characteristics of flat aluminum panels with uniaxial in-plane stresses are presented and discussed. These test results indicate an important improvement in the noise reduction of these panels in the frequency range below the fundamental panel/cavity frequency.

  15. Influence of growth conditions and surface reaction byproducts on GaN grown via metal organic molecular beam epitaxy: Toward an understanding of surface reaction chemistry

    Science.gov (United States)

    Pritchett, David; Henderson, Walter; Burnham, Shawn D.; Doolittle, W. Alan

    2006-04-01

    The surface reaction byproducts during the growth of GaN films via metal organic molecular beam epitaxy (MOMBE) were investigated as a means to optimize material properties. Ethylene and ethane were identified as the dominant surface reaction hydrocarbon byproducts, averaging 27.63% and 7.15% of the total gas content present during growth. Intense ultraviolet (UV) photoexcitation during growth was found to significantly increase the abundance of ethylene and ethane while reducing the presence of H2 and N2. At 920°C, UV excitation was shown to enhance growth rate and crystalline quality while reducing carbon incorporation. Over a limited growth condition range, a 4.5×1019-3.4×1020 cm-3 variation in carbon incorporation was achieved at constant high vacuum. Coupled with growth rate gains, UV excitation yielded films with ˜58% less integrated carbon content. Structural material property variations are reported for various ammonia flows and growth temperatures. The results suggest that high carbon incorporation can be achieved and regulated during MOMBE growth and that in-situ optimization through hydrocarbon analysis may provide further enhancement in the allowable carbon concentration range.

  16. Neutral beam monitoring

    International Nuclear Information System (INIS)

    Fink, J.H.

    1979-01-01

    A neutral beam generated by passing accelerated ions through a walled cell containing a low energy neutral gas, such that charge exchange partially neutralizes the high energy beam, is monitored by detecting the current flowing through the cell wall produced by low energy ions which drift to the wall after the charge exchange. By segmenting the wall into radial and longitudinal segments various beam conditions are identified. (U.K.)

  17. Highly ordered nanopatterns on Ge and Si surfaces by ion beam sputtering

    International Nuclear Information System (INIS)

    Ziberi, B; Cornejo, M; Frost, F; Rauschenbach, B

    2009-01-01

    The bombardment of surfaces with low-energy ion beams leads to material erosion and can be accompanied by changes in the topography. Under certain conditions this surface erosion can result in well-ordered nanostructures. Here an overview of the pattern formation on Si and Ge surfaces under low-energy ion beam erosion at room temperature will be given. In particular, the formation of ripple and dot patterns, and the influence of different process parameters on their formation, ordering, shape and type will be discussed. Furthermore, the internal ion beam parameters inherent to broad beam ion sources are considered as an additional degree of freedom for controlling the pattern formation process. In this context: (i) formation of ripples at near-normal ion incidence, (ii) formation of dots at oblique ion incidence without sample rotation, (iii) transition between patterns, (iv) formation of ripples with different orientations and (v) long range ordered dot patterns will be presented and discussed.

  18. Modulation of controlled-not gate using light beams carrying orbital angular momentum in a nonlinear atomic vapor

    Science.gov (United States)

    Zhang, Yan; Li, YuanYuan; Zhang, YunZhe

    2018-03-01

    We propose and experimentally demonstrate a controlled-not gate with light beams carrying orbital angular momentum (OAM) through a degenerate four-wave mixing process via a photonic band gap structure satisfying the phase-matching condition. By employing the different topological charges of a Laguerre-Gaussian beam as a qubit in this nonlinear process, the controlled-not gate with OAM can be realized. Moreover, we investigate the evolution of the controlled-not gate, which can be modulated by the frequency and the power of the incident beam, i.e., under electromagnetically induced transparency conditions. The study results are useful for applications in quantum communication and information storage.

  19. Circadian rhythms in the incidence of apoptotic cells and number of clonogenic cells in intestinal crypts after radiation using normal and reversed light conditions

    International Nuclear Information System (INIS)

    Ijiri, K.; Potten, C.S.

    1988-01-01

    Variations in the number of radiation-induced morphologically dead or dying cells (apoptotic cells) in the crypts in the small intestine of the mouse have been studied throughout a 24-h period under a normal light regimen. A clear circadian rhythm was displayed in the apoptotic incidence 3 or 6 h after irradiation for each gamma-ray dose studied (range 0.14-9.0 Gy). The most prominent circadian rhythm was obtained after 0.5 Gy. Peak time of day for inducing apoptosis was 06.00-09.00 h, and the trough occurred at 18.00-21.00 h. Some mice were also transferred to a reversed light cycle, and irradiated on different days after transfer. Apoptosis induced by 0.5 Gy or 9.0 Gy, or number of surviving crypts (microcolonies) after 11.0 Gy or 13.0 Gy was examined. The transition point for reversal of circadian rhythm in apoptosis (after 0.5 Gy) occurred 7 days after transfer and the rhythm was reversed by 14 days. The rhythm for crypt survival (i.e. for clonogenic cell radiosensitivity) was disturbed on 1 day and transition point for reversal occurred 3 days after transfer. The rhythm became reversed by 7 days. (author)

  20. Improvement of Galilean refractive beam shaping system for accurately generating near-diffraction-limited flattop beam with arbitrary beam size.

    Science.gov (United States)

    Ma, Haotong; Liu, Zejin; Jiang, Pengzhi; Xu, Xiaojun; Du, Shaojun

    2011-07-04

    We propose and demonstrate the improvement of conventional Galilean refractive beam shaping system for accurately generating near-diffraction-limited flattop beam with arbitrary beam size. Based on the detailed study of the refractive beam shaping system, we found that the conventional Galilean beam shaper can only work well for the magnifying beam shaping. Taking the transformation of input beam with Gaussian irradiance distribution into target beam with high order Fermi-Dirac flattop profile as an example, the shaper can only work well at the condition that the size of input and target beam meets R(0) ≥ 1.3 w(0). For the improvement, the shaper is regarded as the combination of magnifying and demagnifying beam shaping system. The surface and phase distributions of the improved Galilean beam shaping system are derived based on Geometric and Fourier Optics. By using the improved Galilean beam shaper, the accurate transformation of input beam with Gaussian irradiance distribution into target beam with flattop irradiance distribution is realized. The irradiance distribution of the output beam is coincident with that of the target beam and the corresponding phase distribution is maintained. The propagation performance of the output beam is greatly improved. Studies of the influences of beam size and beam order on the improved Galilean beam shaping system show that restriction of beam size has been greatly reduced. This improvement can also be used to redistribute the input beam with complicated irradiance distribution into output beam with complicated irradiance distribution.

  1. Coherent beam-beam effects

    International Nuclear Information System (INIS)

    Chao, A.W.

    1992-01-01

    There are two physical pictures that describe the beam-beam interaction in a storage ring collider: The weak-strong and the strong-strong pictures. Both pictures play a role in determining the beam-beam behavior. This review addresses only the strong-strong picture. The corresponding beam dynamical effects are referred to as the coherent beam-beam effects. Some basic knowledge of the weak-strong picture is assumed. To be specific, two beams of opposite charges are considered. (orig.)

  2. Longitudinal beam dynamics

    International Nuclear Information System (INIS)

    Tecker, F

    2014-01-01

    The course gives a summary of longitudinal beam dynamics for both linear and circular accelerators. After discussing different types of acceleration methods and synchronism conditions, it focuses on the particle motion in synchrotrons

  3. Radioactive beam production at the Bevalac

    International Nuclear Information System (INIS)

    Alonso, J.R.; Feinberg, B.; Kalnins, J.G.; Krebs, G.F.; McMahan, M.A.; Tanihata, I.

    1989-10-01

    At the Bevalac radioactive beams are routinely produced by the fragmentation process. The effectiveness of this process with respect to the secondary beam's emittance, intensity and energy spread depends critically on the nuclear reaction kinematics and the magnitude of the incident beam energy. When this beam energy significantly exceeds the energies of the nuclear reaction process, many of the qualities of the incident beam can be passed on to the secondary beam. Factors affecting secondary beam quality are discussed along with techniques for isolating and purifying a specific reaction product. The on-going radioactive beam program at the Bevalac is used as an example with applications, present performance and plans for the future. 6 refs., 6 figs., 1 tab

  4. Supersonic molecular beam experiments on surface chemical reactions.

    Science.gov (United States)

    Okada, Michio

    2014-10-01

    The interaction of a molecule and a surface is important in various fields, and in particular in complex systems like biomaterials and their related chemistry. However, the detailed understanding of the elementary steps in the surface chemistry, for example, stereodynamics, is still insufficient even for simple model systems. In this Personal Account, I review our recent studies of chemical reactions on single-crystalline Cu and Si surfaces induced by hyperthermal oxygen molecular beams and by oriented molecular beams, respectively. Studies of oxide formation on Cu induced by hyperthermal molecular beams demonstrate a significant role of the translational energy of the incident molecules. The use of hyperthermal molecular beams enables us to open up new chemical reaction paths specific for the hyperthermal energy region, and to develop new methods for the fabrication of thin films. On the other hand, oriented molecular beams also demonstrate the possibility of understanding surface chemical reactions in detail by varying the orientation of the incident molecules. The steric effects found on Si surfaces hint at new ways of material fabrication on Si surfaces. Controlling the initial conditions of incoming molecules is a powerful tool for finely monitoring the elementary step of the surface chemical reactions and creating new materials on surfaces. Copyright © 2014 The Chemical Society of Japan and Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. A Resistive Wideband Space Beam Splitter

    OpenAIRE

    Mahesh, Nivedita; Subrahmanyan, Ravi; Shankar, N. Udaya; Raghunathan, Agaram

    2014-01-01

    We present the design, construction and measurements of the electromagnetic performance of a wideband space beam splitter. The beam splitter is designed to power divide the incident radiation into reflected and transmitted components for interferometer measurement of spectral features in the mean cosmic radio background. Analysis of a 2-element interferometer configuration with a vertical beam splitter between a pair of antennas leads to the requirement that the beam splitter be a resistive s...

  6. Formation of grown-in defects in molecular beam epitaxial Ga(In)NP: Effects of growth conditions and postgrowth treatments

    International Nuclear Information System (INIS)

    Dagnelund, D.; Buyanova, I. A.; Wang, X. J.; Chen, W. M.; Utsumi, A.; Furukawa, Y.; Wakahara, A.; Yonezu, H.

    2008-01-01

    Effects of growth conditions and post-growth treatments, such as presence of N ions, N 2 flow, growth temperature, In alloying, and postgrowth rapid thermal annealing (RTA), on formation of grown-in defects in Ga(In)NP prepared by molecular beam epitaxy are studied in detail by the optically detected magnetic resonance (ODMR) technique. Several common residual defects, such as two Ga-interstitial defects (i.e., Ga i -A and Ga i -B) and two unidentified defects with a g factor around 2 (denoted by S1 and S2), are closely monitored. Bombardment of impinging N ions on grown sample surface is found to facilitate formation of these defects. Higher N 2 flow is shown to have an even more profound effect than a higher number of ions in introducing these defects. Incorporation of a small amount of In (e.g., 5.1%) in GaNP seems to play a minor role in the formation of the defects. In GaInNP with 45% of In; however, the defects were found to be abundant. Effect of RTA on the defects is found to depend on initial configurations of Ga i -related defects formed during the growth. In the alloys where the Ga i -A and Ga i -B defects are absent in the as-grown samples (i.e., GaNP grown at a low temperature of 460 deg. C), the concentrations of the two Ga i defects are found to increase after postgrowth RTA. This indicates that the defects originally introduced in the as-grown alloys have been transformed into the more thermally stable Ga i -A and Ga i -B during RTA. On the other hand, when the Ga i -A and Ga i -B are readily abundant (e.g., at higher growth temperatures (≥500 deg. C), RTA leads to a slight reduction of the Ga i -A and Ga i -B ODMR signals. The S2 defect is also shown to be thermally stable upon the RTA treatment

  7. Acoustic manipulation: Bessel beams and active carriers

    Science.gov (United States)

    Rajabi, Majid; Mojahed, Alireza

    2017-10-01

    In this paper, we address the interaction of zero-order acoustic Bessel beams as an acoustic manipulation tool, with an active spherical shell, as a carrier in drug, agent, or material delivery systems, in order to investigate the controllability of exerted acoustic radiation force as the driver. The active body is comprised of a spherical elastic shell stimulated in its monopole mode of vibrations with the same frequency as the incident wave field via an internally bonded and spatially uniformly excited piezoelectric actuator. The main aim of this work is to examine the performance of a nondiffracting and self-reconstructing zero-order Bessel beam to obtain the full manipulability condition of active carriers in comparison with the case of a plane wave field. The results unveil some unique potentials of the Bessel beams in the company of active carriers, with emphasis on the consumed power of the actuation system. This paper will widen the path toward the single-beam robust acoustic manipulation techniques and may lead to the prospect of combined tweezers and fields, with applications in delivery systems, microswimmers, and trapper designs.

  8. Buildup of electrons with hot electron beam injection into a homogeneous magnetic field

    International Nuclear Information System (INIS)

    Bashko, V.A.; Krivoruchko, A.M.; Tarasov, I.K.

    1989-01-01

    The injection of the monoenergetic beam of electrons into the vacuum drift channel under the conditions when the beam current exceeds a certain threshold value involves a virtual cathode creation. The process of virtual cathode creation leads to an exchange of one-fluid movement of beam particles to three-fluid one corresponding to incident, reflected and passed through anticathode beam particles. For the monoenergetic beam case when the velocity spread Δv dr (v dr is the beam drift velocity), the beam instability was predicted in theory and was observed in experiment. Meanwhile, the injection in the drift space of the 'hot' beam having finite spread in velocities may be accompanied not only by the reflection of particles if their velocity v 1/2 (where φ is the electrostatic potential dip value, e and m are the electron charge and mass, respectively), but also the mutual Coulomb scattering of incident and reflected electrons. The scattering process leads in its turn to appearance of viscosity forces and to trapping of a part of beam electrons into the effective potential well formed by electrostatic potential dip and the viscous force potential. The interaction of travelling and trapped particles may occur even at the stage preceding the virtual electrode formation and it may influence the process of its appearance and also the current flow through the drift space. In this report there are described the experimental results on accumulation of electrons when electron beam propagates in vacuum and has a large spread in particle velocities Δv dr in the homogeneous longitudinal magnetic field when ω pe He where ω pe is the electron Langmuir frequency of beam electrons, ω He is the electron cyclotron frequency. (author) 6 refs., 2 figs

  9. Optical pulling force on a magneto-dielectric Rayleigh sphere in Bessel tractor polarized beams

    International Nuclear Information System (INIS)

    Mitri, F.G.; Li, R.X.; Yang, R.P.; Guo, L.X.; Ding, C.Y.

    2016-01-01

    The optical radiation force induced by Bessel (vortex) beams on a magneto-dielectric subwavelength sphere is investigated with particular emphasis on the beam polarization and order l (or topological charge). The analysis is focused on identifying the regions and some of the conditions to achieve retrograde motion of the sphere centered on the axis of wave propagation of the incident beam, or shifted off-axially. Exact non-paraxial analytical solutions are established, and computations for linear, circular, radial, azimuthal and mixed polarizations of the individual plane wave components forming the Bessel (vortex) beams by means of the angular spectrum decomposition method (ASDM) illustrate the theory with particular emphasis on the tractor (i.e. reversal) behavior of the force. This effect results in the pulling of the magneto-dielectric sphere against the forward linear momentum density flux associated with the incoming waves. Should some conditions related to the choice of the beam parameters as well as the permittivity and permeability of the sphere be met, the optical force vanishes and reverses sign. Moreover, the beam polarization is shown to affect differently the axial negative pulling force for either the zeroth- or the first-order Bessel beam. When the sphere is centered on the beam′s axis, the axial force component is always negative for the zeroth-order Bessel beam except for the radial and azimuthal polarization configurations. Nonetheless, for the first-order Bessel beam, the axial force is negative for the radial polarization case only. Additional tractor beam effects arise when the sphere departs from the center of the beam. It is also demonstrated that the tractor beam effect arises from the force component originating from the cross-interaction between the electric and magnetic dipoles. Potential applications are in particle manipulation, optical levitation, tractor beam tweezers, and other emergent technologies using polarized Bessel beams on

  10. Angularly symmetric splitting of a light beam upon reflection and refraction at an air-dielectric plane boundary.

    Science.gov (United States)

    Azzam, R M A

    2015-12-01

    Conditions for achieving equal and opposite angular deflections of a light beam by reflection and refraction at an air-dielectric boundary are determined. Such angularly symmetric beam splitting (ASBS) is possible only if the angle of incidence is >60° by exactly one third of the angle of refraction. This simple law, plus Snell's law, leads to several analytical results that clarify all aspects of this phenomenon. In particular, it is shown that the intensities of the two symmetrically deflected beams can be equalized by proper choice of the prism refractive index and the azimuth of incident linearly polarized light. ASBS enables a geometrically attractive layout of optical systems that employ multiple prism beam splitters.

  11. Photon beam position monitor

    Science.gov (United States)

    Kuzay, Tuncer M.; Shu, Deming

    1995-01-01

    A photon beam position monitor for use in the front end of a beamline of a high heat flux and high energy photon source such as a synchrotron radiation storage ring detects and measures the position and, when a pair of such monitors are used in tandem, the slope of a photon beam emanating from an insertion device such as a wiggler or an undulator inserted in the straight sections of the ring. The photon beam position monitor includes a plurality of spaced blades for precisely locating the photon beam, with each blade comprised of chemical vapor deposition (CVD) diamond with an outer metal coating of a photon sensitive metal such as tungsten, molybdenum, etc., which combination emits electrons when a high energy photon beam is incident upon the blade. Two such monitors are contemplated for use in the front end of the beamline, with the two monitors having vertically and horizontally offset detector blades to avoid blade "shadowing". Provision is made for aligning the detector blades with the photon beam and limiting detector blade temperature during operation.

  12. Beam loading

    OpenAIRE

    Boussard, Daniel

    1987-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superco...

  13. Molecular beams

    International Nuclear Information System (INIS)

    Pendelbury, J.M.; Smith, K.F.

    1987-01-01

    Studies with directed collision-free beams of particles continue to play an important role in the development of modern physics and chemistry. The deflections suffered by such beams as they pass through electric and magnetic fields or laser radiation provide some of the most direct information about the individual constituents of the beam; the scattering observed when two beams intersect yields important data about the intermolecular forces responsible for the scattering. (author)

  14. New optical scheme for differential measurements of diffraction reflection intensity on X-radiation sliding incidence

    International Nuclear Information System (INIS)

    Golovin, A.L.; Mas', E.T.

    1989-01-01

    An X-ray optical scheme for differential measurements of X-ray diffraction under sliding incidence conditions is proposed and an attachment design realizng this scheme, using standard equipment, is described. The main feature of the scheme is the following: collimation according to the Bragg angle is carried out for the reflected beam rather than the incident one. Goniometers can be used from DRON, TRS, GS-5 and other spectrometers. The goniometer head carrying the sample is standard, it is a part of the DRON, TRS and DTS. The crystal analyzer is fixed on the attachment. The angular position of the crystal monochromator is controlled by an inductive sensor. The experimental differential curves of X-ray diffraction under conditions of sliding incidence, taken for a silicon crystal having the 111 orientation, are given as well

  15. Maximum Credible Incidents

    CERN Document Server

    Strait, J

    2009-01-01

    Following the incident in sector 34, considerable effort has been made to improve the systems for detecting similar faults and to improve the safety systems to limit the damage if a similar incident should occur. Nevertheless, even after the consolidation and repairs are completed, other faults may still occur in the superconducting magnet systems, which could result in damage to the LHC. Such faults include both direct failures of a particular component or system, or an incorrect response to a “normal” upset condition, for example a quench. I will review a range of faults which could be reasonably expected to occur in the superconducting magnet systems, and which could result in substantial damage and down-time to the LHC. I will evaluate the probability and the consequences of such faults, and suggest what mitigations, if any, are possible to protect against each.

  16. VIVITRON beam transport

    International Nuclear Information System (INIS)

    Nadji, A.

    1989-07-01

    The VIVITRON is a new 35 MV particle accelerator which presents a great number of innovations. One of the major problem is the beam transport in this electrostatic machine of 50 m length for ions with masses between 1 and 200. Our work consisted in the study of various experimental and theoretical aspects of the beam transport in Tandem accelerators from the ion source to the analysing magnet. Calculations of the beam optics were performed with a Strasbourg version of the computer code Transport. They allowed us to optimize the beam transport parameters of the VIVITRON elements. Special attention has been focused on the design of the charge state selector to be installed in the terminal of the new machine. Beam transmission measurements were carried out in the Strasbourg MP 10 Tandem accelerator for ions beams of masses between 1 and 127 and for terminal voltages from 9 to 15 MV. Partial and total transmissions were obtained and explanations of the beam losses were proposed in terms of the vacuum pressure and/or the optics of the beam accelerator system. The results have been extrapolated to the VIVITRON for which the best working conditions are now clearly defined [fr

  17. Dual-beam focused ion beam/electron microscopy processing and metrology of redeposition during ion-surface 3D interactions, from micromachining to self-organized picostructures.

    Science.gov (United States)

    Moberlychan, Warren J

    2009-06-03

    Focused ion beam (FIB) tools have become a mainstay for processing and metrology of small structures. In order to expand the understanding of an ion impinging a surface (Sigmund sputtering theory) to our processing of small structures, the significance of 3D boundary conditions must be realized. We consider ion erosion for patterning/lithography, and optimize yields using the angle of incidence and chemical enhancement, but we find that the critical 3D parameters are aspect ratio and redeposition. We consider focused ion beam sputtering for micromachining small holes through membranes, but we find that the critical 3D considerations are implantation and redeposition. We consider ion beam self-assembly of nanostructures, but we find that control of the redeposition by ion and/or electron beams enables the growth of nanostructures and picostructures.

  18. Development of a highway incident management operational and training guide for incident responders in Illinois.

    Science.gov (United States)

    2011-08-01

    Each year highway traffic incidents, such as crashes, place responders on and beside roadways with : dangerous high-speed traffic. The unexpected conditions of an incident scene have the potential to surprise : unsuspecting or inattentive drivers, po...

  19. Beam diagnostics

    International Nuclear Information System (INIS)

    Bogaty, J.; Clifft, B.E.; Zinkann, G.P.; Pardo, R.C.

    1995-01-01

    The ECR-PII injector beam line is operated at a fixed ion velocity. The platform high voltage is chosen so that all ions have a velocity of 0.0085c at the PII entrance. If a previous tune configuration for the linac is to be used, the beam arrival time must be matched to the previous tune as well. A nondestructive beam-phase pickup detector was developed and installed at the entrance to the PII linac. This device provides continuous phase and beam current information and allows quick optimization of the beam injected into PII. Bunches traverse a short tubular electrode thereby inducing displacement currents. These currents are brought outside the vacuum interface where a lumped inductance resonates electrode capacitance at one of the bunching harmonic frequencies. This configuration yields a basic sensitivity of a few hundred millivolts signal per microampere of beam current. Beam-induced radiofrequency signals are summed against an offset frequency generated by our master oscillator. The resulting kilohertz difference frequency conveys beam intensity and bunch phase information which is sent to separate processing channels. One channel utilizes a phase locked loop which stabilizes phase readings if beam is unstable. The other channel uses a linear full wave active rectifier circuit which converts kilohertz sine wave signal amplitude to a D.C. voltage representing beam current. A prototype set of electronics is now in use with the detector and we began to use the system in operation to set the arrival beam phase. A permanent version of the electronics system for the phase detector is now under construction. Additional nondestructive beam intensity and phase monitors at the open-quotes Boosterclose quotes and open-quotes ATLASclose quotes linac sections are planned as well as on some of the high-energy beam lines. Such a monitor will be particularly useful for FMA experiments where the primary beam hits one of the electric deflector plates

  20. PARTICLE BEAMS: Frontier course

    International Nuclear Information System (INIS)

    Anon.

    1987-01-01

    Driven by the quest for higher energies and optimal physics conditions, the behaviour of particle beams in accelerators and storage rings is the subject of increasing attention. Thus the second course organized jointly by the US and CERN Accelerator Schools looked towards the frontiers of particle beam knowledge. The programme held at South Padre Island, Texas, from 23-29 October attracted 125 participants including some 35 from Europe

  1. PARTICLE BEAMS: Frontier course

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1987-01-15

    Driven by the quest for higher energies and optimal physics conditions, the behaviour of particle beams in accelerators and storage rings is the subject of increasing attention. Thus the second course organized jointly by the US and CERN Accelerator Schools looked towards the frontiers of particle beam knowledge. The programme held at South Padre Island, Texas, from 23-29 October attracted 125 participants including some 35 from Europe.

  2. Study on the conditions of proton beam shaping in the ion source of the AN USSR IYaI meson factory

    International Nuclear Information System (INIS)

    Esin, S.K.; Yakushev, V.P.; Frolov, O.T.; Polulyakh, V.P.

    1981-01-01

    The results of measuring proton beam emittance in ion source- duaplasmatron with tungsten-barium direct-heated cathode intended for 750 keV injector of the linear accelerator are presented. The system of ion extraction comprises an expander and extraction grid. Peculiarities of primary beam formation at different configurations of the expander: a) expander in the form of a cylinder, b) comical expander, c) the same conical expander but with a splitter installed behind the anode window and permitting to cut off the central part of plasma flux; ''sectional'' expander made of 5 separated from one another similar metal rings of 16 mm height fixed in the cylinder made of insulator, are studied. The diameter of the duaplasmatron window equals 0.8 mm. It is shown that beam formation with the help of cylindrical and conical with a splitter expanders meet the requirements of the proton injector and well satisfy the aperture of the channel of the accelerating tube of 54 mm diameter [ru

  3. The effect of metal-rich growth conditions on the microstructure of Sc{sub x}Ga{sub 1-x}N films grown using molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Tsui, H.C.L.; Moram, M.A. [Department of Materials, Imperial College London (United Kingdom); Goff, L.E. [Department of Materials, Imperial College London (United Kingdom); Department of Physics, University of Cambridge (United Kingdom); Barradas, N.P. [CTN - Centro de Ciencias e Tecnologias Nucleares, Instituto Superior Tecnico, Universidade de Lisboa, Bobadela LRS (Portugal); Alves, E. [IPFN - Instituto de Plasmas e Fusao Nuclear, Lisboa (Portugal); Laboratorio de Aceleradores e Tecnologias de Radiacao, Instituto Superior Tecnico, Universidade de Lisboa, Bobadela LRS (Portugal); Pereira, S. [CICECO and Department of Physics, Universidade de Aveiro (Portugal); Beere, H.E.; Farrer, I.; Nicoll, C.A.; Ritchie, D.A. [Department of Physics, University of Cambridge (United Kingdom)

    2015-12-15

    Epitaxial Sc{sub x}Ga{sub 1-x}N films with 0 ≤ x ≤ 0.50 were grown using molecular beam epitaxy under metal-rich conditions. The Sc{sub x}Ga{sub 1-x}N growth rate increased with increasing Sc flux despite the use of metal-rich growth conditions, which is attributed to the catalytic decomposition of N{sub 2} induced by the presence of Sc. Microstructural analysis showed that phase-pure wurtzite Sc{sub x}Ga{sub 1-x}N was achieved up to x = 0.26, which is significantly higher than that previously reported for nitrogen-rich conditions, indicating that the use of metal-rich conditions can help to stabilise wurtzite phase Sc{sub x}Ga{sub 1-x}N. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. SPS Machine Protection Incident in 2009

    CERN Document Server

    Wenninger, J

    2009-01-01

    During the 008 SPS run a single machine operation incident happened on June 27th when a high intensity CNGS beam was lost in a dipole of sextant 1 following a time system ‘freeze’. The vacuum chamber was punctured over a length of over 10 cm, and the vacuum in the affected sector rose to atmospheric pressure. The dipole was exchanged June 30th. This note describes the incident in detail and presents the measures taken to avoid a similar incident in the future.

  5. TPX/TFTR Neutral Beam energy absorbers

    International Nuclear Information System (INIS)

    Dahlgren, F.; Wright, K.; Kamperschroer, J.; Grisham, L.; Lontai, L.; Peters, C.; VonHalle, A.

    1993-01-01

    The present beam energy absorbing surfaces on the TFTR Neutral Beams such as Ion Dumps, Calorimeters, beam defining apertures, and scrapers, are simple water cooled copper plates which wee designed to absorb (via their thermal inertia) the incident beam power for two seconds with a five minute coal down interval between pulses. These components are not capable of absorbing the anticipated beam power loading for 1000 second TPX pulses and will have to be replaced with an actively cooled design. While several actively cooled energy absorbing designs were considered,, the hypervapotron elements currently being used on the JET beamlines were chosen due to their lower cooling water demands and reliable performance on JET

  6. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  7. Beam loading

    International Nuclear Information System (INIS)

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed. (author)

  8. Ion-source dependence of the distributions of internuclear separations in 2-MeV HeH+ beams

    International Nuclear Information System (INIS)

    Kanter, E.P.; Gemmell, D.S.; Plesser, I.; Vager, Z.

    1981-01-01

    Experiments involving the use of MeV molecular-ion beams have yielded new information on atomic collisions in solids. A central part of the analyses of such experiments is a knowledge of the distribution of internuclear separations contained in the incident beam. In an attempt to determine how these distributions depend on ion-source gas conditions, we have studied foil-induced dissociations of H 2+ , H 3+ , HeH + , and OH 2+ ions. Although changes of ion-source gas compositions and pressure were found to have no measurable influence on the vibrational state populations of the beams reaching our target, for HeH + we found that beams produced in our rf source were vibrationally hotter than beams produced in a duoplasmatron. This was also seen in studies of neutral fragments and transmitted molecules

  9. Novel neutralized-beam intense neutron source for fusion technology development

    International Nuclear Information System (INIS)

    Osher, J.E.; Perkins, L.J.

    1983-01-01

    We describe a neutralized-beam intense neutron source (NBINS) as a relevant application of fusion technology for the type of high-current ion sources and neutral beamlines now being developed for heating and fueling of magnetic-fusion-energy confinement systems. This near-term application would support parallel development of highly reliable steady-state higher-voltage neutral D 0 and T 0 beams and provide a relatively inexpensive source of fusion neutrons for materials testing at up to reactor-like wall conditions. Beam-target examples described incude a 50-A mixed D-T total (ions plus neutrals) space-charge-neutralized beam at 120 keV incident on a liquid Li drive-in target, or a 50-A T 0 + T + space-charge-neutralized beam incident on either a LiD or gas D 2 target with calculated 14-MeV neutron yields of 2 x 10 15 /s, 7 x 10 15 /s, or 1.6 x 10 16 /s, respectively. The severe local heat loading on the target surface is expected to limit the allowed beam focus and minimum target size to greater than or equal to 25 cm 2

  10. Analysis of Surface Dose Refer to Distance between Beam Spoiler and Patient in Total Body Irradiation

    International Nuclear Information System (INIS)

    Choi, Jong Hwan; Kim, Jong Sik; Choi, Ji Min; Shin, Eun Hyuk; Song, Ki Won; Park, Young Hwan

    2007-01-01

    Total body irradiation is used to kill the total malignant cell and for immunosuppression component of preparatory regimens for bone-marrow restitution of patients. Beam spoiler is used to increase the dose to the superficial tissues. This paper finds the property of the distance between beam spoiler and patient. Set-up conditions are 6 MV-Xray, 300 MU, SAD = 400 cm, field size = 40 x 40 cm 2 . The parallel plate chamber located in surface, midpoint and exit of solid water phantom. The surface dose is measured while the distance between beam spoiler and patient is altered. Because it should be found proper distance. The solid water phantom is fixer and beam spoiler is moving. Central dose of phantom is 10.7 cGy and exit dose is 6.7 cGy. In case of distance of 50 cm to 60 cm between beam spoiler and solid water phantom, incidence dose is 14.58-14.92 cGy. Therefore, The surface dose was measured 99.4-101% with got near most to the prescription dose. In clinical case, distance between beam spoiler and patient affect surface dose. If once 50-60 cm of distance between beam spoiler and patient, surface dose of patient got near prescription dose. It would be taken distance between beam spoiler and patient into account in clinical therapy.

  11. A pioneer experience in Malaysia on In-house Radio-labelling of (131)I-rituximab in the treatment of Non-Hodgkin's Lymphoma and a case report of high dose (131)I-rituximab-BEAM conditioning autologous transplant.

    Science.gov (United States)

    Kuan, Jew Win; Law, Chiong Soon; Wong, Xiang Qi; Ko, Ching Tiong; Awang, Zool Hilmi; Chew, Lee Ping; Chang, Kian Meng

    2016-10-01

    Radioimmunotherapy is an established treatment modality in Non-Hodgkin's lymphoma. The only two commercially available radioimmunotherapies - (90)Y-ibritumomab tiuxetan is expensive and (131)I-tositumomab has been discontinued from commercial production. In resource limited environment, self-labelling (131)I-rituximab might be the only viable practical option. We reported our pioneer experience in Malaysia on self-labelling (131)I-rituximab, substituting autologous haematopoietic stem cell transplantation (HSCT) and a patient, the first reported case, received high dose (131)I-rituximab (6000MBq/163mCi) combined with BEAM conditioning for autologous HSCT. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Superresolution beams

    CSIR Research Space (South Africa)

    Ngcobo, S

    2011-11-01

    Full Text Available The transformation of a Gaussian beam (GB) into a symmetrical higher order TEMp0 Laguerre Gaussian beam (LGB) intensity distribution of which is further rectified and transformed into a Gaussian intensity distribution in the plane of a converging...

  13. Nonpolarizing beam splitter designed by frustrated total internal reflection inside a glass cube.

    Science.gov (United States)

    Xu, Xueke; Shao, Jianda; Fan, Zhengxiu

    2006-06-20

    A method for the design of an all-dielectric nonpolarizing prism beam splitter utilizing the principle of frustrated total internal reflection is reported. The nonpolarizing condition for a prism beam splitter is discussed, and some single layer design examples are elaborated. The concept can be applied to a wide range of wavelengths and arbitrary transmittance values, and with the help of a computer design program examples of 400-700 nm, T(p)=T(s)=0.5+/-0.01, with incident angles of 45 degrees and 62 degrees are given. In addition, the sensitivity and application of the design are also discussed.

  14. Surface nanostructuring of TiO2 thin films by ion beam irradiation

    International Nuclear Information System (INIS)

    Romero-Gomez, P.; Palmero, A.; Yubero, F.; Vinnichenko, M.; Kolitsch, A.; Gonzalez-Elipe, A.R.

    2009-01-01

    This work reports a procedure to modify the surface nanostructure of TiO 2 anatase thin films through ion beam irradiation with energies in the keV range. Irradiation with N + ions leads to the formation of a layer with voids at a depth similar to the ion-projected range. By setting the ion-projected range a few tens of nanometers below the surface of the film, well-ordered nanorods appear aligned with the angle of incidence of the ion beam. Slightly different results were obtained by using heavier (S + ) and lighter (B + ) ions under similar conditions

  15. Dependence of extinction cross-section on incident polarization state and particle orientation

    International Nuclear Information System (INIS)

    Yang Ping; Wendisch, Manfred; Bi Lei; Kattawar, George; Mishchenko, Michael; Hu, Yongxiang

    2011-01-01

    This note reports on the effects of the polarization state of an incident quasi-monochromatic parallel beam of radiation and the orientation of a hexagonal ice particle with respect to the incident direction on the extinction process. When the incident beam is aligned with the six-fold rotational symmetry axis, the extinction is independent of the polarization state of the incident light. For other orientations, the extinction cross-section for linearly polarized light can be either larger or smaller than its counterpart for an unpolarized incident beam. Therefore, the attenuation of a quasi-monochromatic radiation beam by an ice cloud depends on the polarization state of the beam if ice crystals within the cloud are not randomly oriented. Furthermore, a case study of the extinction of light by a quartz particle is also presented to illustrate the dependence of the extinction cross-section on the polarization state of the incident light.

  16. Coherent beam-beam effect

    International Nuclear Information System (INIS)

    Chao, A.W.; Keil, E.

    1979-06-01

    The stability of the coherent beam-beam effect between rigid bunches is studied analytically and numerically for a linear force by evaluating eigenvalues. For a realistic force, the stability is investigated by following the bunches for many revolutions. 4 refs., 13 figs., 2 tabs

  17. Crystalline beams: The vertical zigzag

    International Nuclear Information System (INIS)

    Haffmans, A.F.; Maletic, D.; Ruggiero, A.G.

    1994-01-01

    This note is the continuation of our comprehensive investigation of Crystalline Beams. After having determined the equations of motion and the conditions for the formation of the simplest configuration, i.e. the string, we study the possibility of storing an intense beam of charged particles in a storage ring where they form a vertical zigzag. We define the equilibrium configuration, and examine the confinement conditions. Subsequently, we derive the transfer matrix for motion through various elements of the storage ring. Finally we investigate the stability conditions for such a beam

  18. A map for the thick beam-beam interaction

    International Nuclear Information System (INIS)

    Irwin, J.; Chen, T.

    1995-01-01

    The authors give a closed-form expression for the thick beam-beam interaction for a small disruption parameter, as typical in electron-positron storage rings. The dependence on transverse angle and position of the particle trajectory as well as the longitudinal position of collision and the waist-modified shape of the beam distribution are included. Large incident angles, as are present for beam-halo particles or for large crossing-angle geometry, are accurately represented. The closed-form expression is well approximated by polynomials times the complex error function. Comparisons with multi-slice representations show even the first order terms are more accurate than a five slice representation, saving a factor of 5 in computation time

  19. Electron beams and applications

    International Nuclear Information System (INIS)

    Haouat, G.; Couillaud, C.

    1998-01-01

    Studies of the physical properties of the ELSA-linac electron beam are presented. They include measurements of the characteristic beam parameter and analyzes of the beam transport using simulation codes. The aim of these studies is to determine the best conditions for production of intense and very short electron bunches and to optimize the transport of space-charge dominated beams. Precise knowledge of the transport dynamics allows to produce beams with the required characteristics for light production in Free-Electron Laser (FEL), and to give a good description of energy-transfer phenomena between electrons and photons in the wriggler. The particular features of ELSA authorize studies of high-intensity, high-brightness beam properties, especially the halo surrounding the dense core of the electron bunches, which is formed by the space charge effects. It is also shown that the ELSA facility is well suited for the fabrication of very short γ and X-rays sources for applied research in nuclear and plasma physics, or for time response studies of fast detectors. (author)

  20. Beam tests of ATLAS SCT silicon strip detector modules

    CERN Document Server

    Campabadal, F; Key, M; Lozano, M; Martínez, C; Pellegrini, G; Rafí, J M; Ullán, M; Johansen, L; Pommeresche, B; Stugu, B; Ciocio, A; Fadeev, V; Gilchriese, M G D; Haber, C; Siegrist, J; Spieler, H; Vu, C; Bell, P J; Charlton, D G; Dowell, John D; Gallop, B J; Homer, R J; Jovanovic, P; Mahout, G; McMahon, T J; Wilson, J A; Barr, A J; Carter, J R; Fromant, B P; Goodrick, M J; Hill, J C; Lester, C G; Palmer, M J; Parker, M A; Robinson, D; Sabetfakhri, A; Shaw, R J; Anghinolfi, F; Chesi, Enrico Guido; Chouridou, S; Fortin, R; Grosse-Knetter, J; Gruwé, M; Ferrari, P; Jarron, P; Kaplon, J; MacPherson, A; Niinikoski, T O; Pernegger, H; Roe, S; Rudge, A; Ruggiero, G; Wallny, R; Weilhammer, P; Bialas, W; Dabrowski, W; Grybos, P; Koperny, S; Blocki, J; Brückman, P; Gadomski, S; Godlewski, J; Górnicki, E; Malecki, P; Moszczynski, A; Stanecka, E; Stodulski, M; Szczygiel, R; Turala, M; Wolter, M; Ahmad, A; Benes, J; Carpentieri, C; Feld, L; Ketterer, C; Ludwig, J; Meinhardt, J; Runge, K; Mikulec, B; Mangin-Brinet, M; D'Onofrio, M; Donega, M; Moêd, S; Sfyrla, A; Ferrère, D; Clark, A G; Perrin, E; Weber, M; Bates, R L; Cheplakov, A P; Saxon, D H; O'Shea, V; Smith, K M; Iwata, Y; Ohsugi, T; Kohriki, T; Kondo, T; Terada, S; Ujiie, N; Ikegami, Y; Unno, Y; Takashima, R; Brodbeck, T; Chilingarov, A G; Hughes, G; Ratoff, P; Sloan, T; Allport, P P; Casse, G L; Greenall, A; Jackson, J N; Jones, T J; King, B T; Maxfield, S J; Smith, N A; Sutcliffe, P; Vossebeld, Joost Herman; Beck, G A; Carter, A A; Lloyd, S L; Martin, A J; Morris, J; Morin, J; Nagai, K; Pritchard, T W; Anderson, B E; Butterworth, J M; Fraser, T J; Jones, T W; Lane, J B; Postranecky, M; Warren, M R M; Cindro, V; Kramberger, G; Mandic, I; Mikuz, M; Duerdoth, I P; Freestone, J; Foster, J M; Ibbotson, M; Loebinger, F K; Pater, J; Snow, S W; Thompson, R J; Atkinson, T M; Bright, G; Kazi, S; Lindsay, S; Moorhead, G F; Taylor, G N; Bachindgagyan, G; Baranova, N; Karmanov, D; Merkine, M; Andricek, L; Bethke, Siegfried; Kudlaty, J; Lutz, Gerhard; Moser, H G; Nisius, R; Richter, R; Schieck, J; Cornelissen, T; Gorfine, G W; Hartjes, F G; Hessey, N P; de Jong, P; Muijs, A J M; Peeters, S J M; Tomeda, Y; Tanaka, R; Nakano, I; Dorholt, O; Danielsen, K M; Huse, T; Sandaker, H; Stapnes, S; Bargassa, Pedrame; Reichold, A; Huffman, T; Nickerson, R B; Weidberg, A; Doucas, G; Hawes, B; Lau, W; Howell, D; Kundu, N; Wastie, R; Böhm, J; Mikestikova, M; Stastny, J; Broklová, Z; Broz, J; Dolezal, Z; Kodys, P; Kubík, P; Reznicek, P; Vorobel, V; Wilhelm, I; Chren, D; Horazdovsky, T; Linhart, V; Pospísil, S; Sinor, M; Solar, M; Sopko, B; Stekl, I; Ardashev, E N; Golovnya, S N; Gorokhov, S A; Kholodenko, A G; Rudenko, R E; Ryadovikov, V N; Vorobev, A P; Adkin, P J; Apsimon, R J; Batchelor, L E; Bizzell, J P; Booker, P; Davis, V R; Easton, J M; Fowler, C; Gibson, M D; Haywood, S J; MacWaters, C; Matheson, J P; Matson, R M; McMahon, S J; Morris, F S; Morrissey, M; Murray, W J; Phillips, P W; Tyndel, M; Villani, E G; Dorfan, D E; Grillo, A A; Rosenbaum, F; Sadrozinski, H F W; Seiden, A; Spencer, E; Wilder, M; Booth, P; Buttar, C M; Dawson, I; Dervan, P; Grigson, C; Harper, R; Moraes, A; Peak, L S; Varvell, K E; Chu Ming Lee; Hou Li Shing; Lee Shih Chang; Teng Ping Kun; Wan Chang Chun; Hara, K; Kato, Y; Kuwano, T; Minagawa, M; Sengoku, H; Bingefors, N; Brenner, R; Ekelöf, T J C; Eklund, L; Bernabeu, J; Civera, J V; Costa, M J; Fuster, J; García, C; García, J E; González-Sevilla, S; Lacasta, C; Llosa, G; Martí i García, S; Modesto, P; Sánchez, J; Sospedra, L; Vos, M; Fasching, D; González, S; Jared, R C; Charles, E

    2005-01-01

    The design and technology of the silicon strip detector modules for the Semiconductor Tracker (SCT) of the ATLAS experiment have been finalised in the last several years. Integral to this process has been the measurement and verification of the tracking performance of the different module types in test beams at the CERN SPS and the KEK PS. Tests have been performed to explore the module performance under various operating conditions including detector bias voltage, magnetic field, incidence angle, and state of irradiation up to 3 multiplied by 1014 protons per square centimetre. A particular emphasis has been the understanding of the operational consequences of the binary readout scheme.

  1. Doppler-shifted neutral beam line shape and beam transmission

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kokatnur, N.; Lagin, L.J.; Newman, R.A.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A.

    1994-04-01

    Analysis of Doppler-shifted Balmer-α line emission from the TFTR neutral beam injection systems has revealed that the line shape is well approximated by the sum of two Gaussians, or, alternatively, by a Lorentzian. For the sum of two Gaussians, the broad portion of the distribution contains 40% of the beam power and has a divergence five times that of the narrow part. Assuming a narrow 1/e- divergence of 1.3 degrees (based on fits to the beam shape on the calorimeter), the broad part has a divergence of 6.9 degrees. The entire line shape is also well approximated by a Lorentzian with a half-maximum divergence of 0.9 degrees. Up to now, fusion neutral beam modelers have assumed a single Gaussian velocity distribution, at the extraction plane, in each direction perpendicular to beam propagation. This predicts a beam transmission efficiency from the ion source to the calorimeter of 97%. Waterflow calorimetry data, however, yield a transmission efficiency of ∼75%, a value in rough agreement with predictions of the Gaussian or Lorentzian models presented here. The broad wing of the two Gaussian distribution also accurately predicts the loss in the neutralizer. An average angle of incidence for beam loss at the exit of the neutralizer is 2.2 degrees, rather than the 4.95 degrees subtended by the center of the ion source. This average angle of incidence, which is used in computing power densities on collimators, is shown to be a function of beam divergence

  2. Continuous Reinforced Concrete Beams

    DEFF Research Database (Denmark)

    Hoang, Cao Linh; Nielsen, Mogens Peter

    1996-01-01

    This report deals with stress and stiffness estimates of continuous reinforced concrete beams with different stiffnesses for negative and positive moments e.g. corresponding to different reinforcement areas in top and bottom. Such conditions are often met in practice.The moment distribution...

  3. Particle reflection and TFTR neutral beam diagnostics

    International Nuclear Information System (INIS)

    Kamperschroer, J.H.; Grisham, L.R.; Kugel, H.W.; O'Connor, T.E.; Newman, R.A.; Stevenson, T.N.; von Halle, A.; Williams, M.D.

    1992-04-01

    Determination of two critical neutral beam parameters, power and divergence, are affected by the reflection of a fraction of the incident energy from the surface of the measuring calorimeter. On the TFTR Neutral Beam Test Stand, greater than 30% of the incident power directed at the target chamber calorimeter was unaccounted for. Most of this loss is believed due to reflection from the surface of the flat calorimeter, which was struck at a near grazing incidence (12 degrees). Beamline calorimeters, of a ''V''-shape design, while retaining the beam power, also suffer from reflection effects. Reflection, in this latter case, artificially peaks the power toward the apex of the ''V'', complicating the fitting technique, and increasing the power density on axis by 10 to 20%; an effect of import to future beamline designers. Agreement is found between measured and expected divergence values, even with 24% of the incident energy reflected

  4. Spatially-Resolved Ion Trajectory Measurements During Cl2 Reactive Ion Beam Etching and Ar Ion Beam Etching

    International Nuclear Information System (INIS)

    Vawter, G. Allen; Woodworth, Joseph R.; Zubrzycki, Walter J.

    1999-01-01

    The angle of ion incidence at the etched wafer location during RIBE and IBE using Cl 2 , Ar and O 2 ion beams has been characterized using an ion energy and angle analyzer. Effects of beam current and accelerator grid bias on beam divergence and the spatial uniformity of the spread of incident angles are measured. It is observed that increased total beam current can lead to reduced current density at the sample stage due to enhanced beam divergence at high currents. Results are related to preferred etch system design for uniform high-aspect-ratio etching across semiconductor wafers

  5. A pencil beam algorithm for helium ion beam therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fuchs, Hermann; Stroebele, Julia; Schreiner, Thomas; Hirtl, Albert; Georg, Dietmar [Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria); PEG MedAustron, 2700 Wiener Neustadt (Austria); Department of Nuclear Medicine, Medical University of Vienna, 1090 Vienna (Austria); Christian Doppler Laboratory for Medical Radiation Research for Radiation Oncology, Medical University of Vienna, 1090 Vienna (Austria); Department of Radiation Oncology, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria) and Comprehensive Cancer Center, Medical University of Vienna/AKH Vienna, 1090 Vienna (Austria)

    2012-11-15

    Purpose: To develop a flexible pencil beam algorithm for helium ion beam therapy. Dose distributions were calculated using the newly developed pencil beam algorithm and validated using Monte Carlo (MC) methods. Methods: The algorithm was based on the established theory of fluence weighted elemental pencil beam (PB) kernels. Using a new real-time splitting approach, a minimization routine selects the optimal shape for each sub-beam. Dose depositions along the beam path were determined using a look-up table (LUT). Data for LUT generation were derived from MC simulations in water using GATE 6.1. For materials other than water, dose depositions were calculated by the algorithm using water-equivalent depth scaling. Lateral beam spreading caused by multiple scattering has been accounted for by implementing a non-local scattering formula developed by Gottschalk. A new nuclear correction was modelled using a Voigt function and implemented by a LUT approach. Validation simulations have been performed using a phantom filled with homogeneous materials or heterogeneous slabs of up to 3 cm. The beams were incident perpendicular to the phantoms surface with initial particle energies ranging from 50 to 250 MeV/A with a total number of 10{sup 7} ions per beam. For comparison a special evaluation software was developed calculating the gamma indices for dose distributions. Results: In homogeneous phantoms, maximum range deviations between PB and MC of less than 1.1% and differences in the width of the distal energy falloff of the Bragg-Peak from 80% to 20% of less than 0.1 mm were found. Heterogeneous phantoms using layered slabs satisfied a {gamma}-index criterion of 2%/2mm of the local value except for some single voxels. For more complex phantoms using laterally arranged bone-air slabs, the {gamma}-index criterion was exceeded in some areas giving a maximum {gamma}-index of 1.75 and 4.9% of the voxels showed {gamma}-index values larger than one. The calculation precision of the

  6. A better beam quality

    CERN Multimedia

    CERN Bulletin

    2010-01-01

    Progress has been made on two fronts, providing physics data and preparing for higher intensities. Over the Whitsun weekend of May 22 to 24, 5 fills for physics provided almost 30 hours of stable colliding beams, all with bunch intensities around 2x1010 protons and at a β* of 2m. The first three of these fills were with 6 bunches per beam, giving 3 pairs of collisions in all experiments. For the other two fills, the number of bunches per beam was increased to 13, giving 8 pairs of colliding bunches, and for the first time luminosities were pushed above 1029 cm-2s-1, 2 orders of magnitude higher than first collisions in March. In between and after these physics fills, nominal bunches of 1011 protons were successfully ramped and brought into collision in ATLAS and CMS for the first time (not in stable beam conditions and without squeeze). Event rates seen by the experiments were in the expected range for these conditions. In the middle of this work, a short fill with beams of 7 nominal bunches was ...

  7. Status of ACCULINNA beam line

    CERN Document Server

    Rodin, A M; Bogdanov, D D; Golovkov, M S; Fomichev, A S; Sidorchuk, S I; Slepnev, R S; Wolski, R; Ter-Akopian, G M; Oganessian, Yu T; Yukhimchuk, A A; Perevozchikov, V V; Vinogradov, Yu I; Grishenchkin, S K; Demin, A M; Zlatoustovskii, S V; Kuryakin, A V; Filchagin, S V; Ilkaev, R I

    2003-01-01

    The separator ACCULINNA was upgraded to achieve new experimental requirements. The beam line was extended by new ion-optical elements beyond the cyclotron hall. The new arrangements yield much better background conditions. The intensities of sup 6 He and sup 8 He radioactive beams produced in fragmentation of 35 A MeV sup 1 sup 1 B ions were increased up to a factor of 10. The upgraded beam line was used in experiments to study the sup 5 H resonance states populated in the t+t reaction. A cryogenic liquid tritium target was designed and installed at the separator beam line.

  8. Beam transport

    International Nuclear Information System (INIS)

    1988-01-01

    Considerable experience has now been gained with the various beam transport lines, and a number of minor changes have been made to improve the ease of operation. These include: replacement of certain little-used slits by profile monitors (harps or scanners); relocation of steering magnets, closer to diagnostic harps or profile scanners; installation of a scanner inside the isocentric neutron therapy system; and conversion of a 2-doublet quadrupole telescope (on the neutron therapy beamline) to a 2-triplet telescope. The beam-swinger project has been delayed by very late delivery of the magnet iron to the manufacturer, but is now progressing smoothly. The K=600 spectrometer magnets have now been delivered and are being assembled for field mapping. The x,y-table with its associated mapping equipment is complete, together with the driver software. One of the experimental areas has been dedicated to the production of collimated neutron beams and has been equipped with a bending magnet and beam dump, together with steel collimators fixed at 4 degrees intervals from 0 degrees to 16 degrees. Changes to the target cooling and shielding system for isotope production have led to a request for much smaller beam spot sizes on target, and preparations have been made for rearrangement of the isotope beamline to permit installation of quadrupole triplets on the three beamlines after the switching magnet. A practical system of quadrupoles for matching beam properties to the spectrometer has been designed. 6 figs

  9. Muon Beam Studies in the H4 beam line and the Gamma Irradiation Facility (GIF++)

    CERN Document Server

    Margraf, Rachel; CERN. Geneva. ATS Department

    2018-01-01

    In this note, we present detailed simulation results for the trajectory of a muon beam, traversing beam zones PPE-134 and PPE-154, produced by a 150 GeV positive hadron beam incident on collimators 9 & 10 in the H4 beam line when these collimators are placed off-beam axis to stop all hadrons and electrons. Using G4Beamline, a GEANT-4 based Monte-Carlo program, the trajectory of the muon beam has been studied for several field strengths of the GOLIATH magnet, as well as for different polarities. The position of the beam at the Gamma Irradiation Facility (GIF++), located downstream the PPE-144 area, is also presented. In addition, two configurations of the two XTDV’s present in the line (XTDV.022.520 and XTDV.022.610) have been studied, with the purpose to simulate the pion contamination of the beam both in PPE134 and GIF++.

  10. Incidência e caraterísticas sociodemográficas de pacientes internados com coronariopatia Incidencia y características sociodemográficas de pacientes internados con coronariopatía Incidence and sociodemographic characteristics of patients with coronary conditions

    Directory of Open Access Journals (Sweden)

    Maria Aparecida Baggio

    2011-12-01

    pacientes atendidos durante el periodo de 2005 a 2009. De ellos, 1.755 son expedientes médicos de hospitalización por infarto de miocardio, 5.977 de procedimientos de angiografía coronaria, 2264 de angioplastia coronaria y 1004 de cirugías de revascularización miocárdica. En función de las variables del estudio, los datos fueron agrupados en tablas y analizados de forma descriptiva. Los enfermos con coronariopatía del sexo masculino (68,55% son más numerosos que los del sexo femenino (31,5%. De los pacientes revascularizados, la mayoría era de raza blanca, baja escolaridad, se encontraba en el grupo etario de los 51 a los 70 años, estaban jubilados y eran originarios de los municipios de São José y Florianópolis. Los datos de incidencia posibilita a los profesionales de enfermería y de la salud planear acciones de cuidado, de promoción y de educación para la salud, y el conocimiento de las características sociodemográficas permite a aquellos profesionales que actúan en la Unidad de Cuidados Intensivos cardiovasculares planear el cuidado del paciente revascularizado.Cardiovascular diseases are the principal cause of death in Brazil. For this reason, the objective of this study is to verify the incidence of the population of inpatients at the Cardiological Institute of Santa Catarina (Instituto de Cardiologia de Santa Catarina for clinical and surgical treatment for coronary conditions and to characterize the socio-demographic characteristics of patients having myocardial revascularization. This is a descriptive, retrospective, cross-sectional study of 11000 records of patients who were attended from 2005 to 2009. Of these, 1755 represent inpatient records for myocardial infarction, 5977 for coronary angiography procedures, 2264 for coronry angioplasty, and 1004 for myocardial revascularization surgery. Depending on the variables of this study, the data were grouped in tables and analyzed descriptively. Male patients with coronary conditions (68

  11. LANSCE Beam Current Limiter (XL)

    International Nuclear Information System (INIS)

    Gallegos, F.R.; Hall, M.J.

    1997-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) is an engineered safety system that provides personnel protection from prompt radiation due to accelerated proton beams. The Beam Current Limiter (XL), as an active component of the RSS, limits the maximum average current in a beamline, thus the current available for a beam spill accident. Exceeding the pre-set limit initiates action by the RSS to mitigate the hazard (insertion of beam stoppers in the low energy beam transport). The beam limiter is an electrically isolated, toroidal transformer and associated electronics. The device was designed to continuously monitor beamline currents independent of any external timing. Fail-safe operation was a prime consideration in its development. Fail-safe operation is defined as functioning as intended (due to redundant circuitry), functioning with a more sensitive fault threshold, or generating a fault condition. This report describes the design philosophy, hardware, implementation, operation, and limitations of the device

  12. Beam dancer fusion device

    International Nuclear Information System (INIS)

    Maier, H.B.

    1984-01-01

    To accomplish fusion of two or more fusion fuel elements numerous minute spots of energy or laser light are directed to a micro target area, there to be moved or danced about by a precision mechanical controlling apparatus at the source of the laser light or electromagnetic energy beams, so that merging and coinciding patterns of light or energy beams can occur around the area of the fuel atoms or ions. The projecting of these merging patterns may be considered as target searching techniques to locate responsive clusters of fuel elements and to compress such elements into a condition in which fusion may occur. Computerized programming may be used

  13. IDENTIFIKASI PROFIL DASAR LAUT MENGGUNAKAN INSTRUMEN SIDE SCAN SONAR DENGAN METODE BEAM PATTERN DISCRETE-EQUI-SPACED UNSHADED LINE ARRAY

    Directory of Open Access Journals (Sweden)

    Muhammad Zainuddin Lubis

    2017-05-01

    which was a sea of Riau Island in Indonesia. Side scan sonar (SSS is an instrument based on sonar system wich capable of showing the image of two-dimensional surface of the seabed with contour conditions, topography, and the underwater target simultaneously. Beam Pattern Discrete-equispaced unshaded Line Array Method is used to compute the two-dimensional beam pattern which depends on the angle of the incoming sound waves from the axis of the array are acceptable depending on the angle at which the sound beam array. This research was conducted in December 2016 in the sea Punggur, Batam, Riau Islands-Indonesia, with coordinate system  104 ° 08,7102 E and 1° 03,2448 N until 1 ° 03.3977N and 104 ° 08,8133 E,  using Side Scan Sonar Tow C-Max CM2 fish instruments with a frequency of 325 kHz. The Results obtained from the recording there are 7 targets, and Beam pattern of Discrete-Beam method Equi-Spaced unshaded Line Array in targets 4 have the highest value in the Pattern is 21:08 dB directivity. The results of the model's beam pattern have anaxis value at the incidence angle (o of the directivity pattern (dB are not on the value 0 or the central beam pattern generated on the target 6 with incident angle -1.5 o and 1.5o have declined by -40 dB. Characteristics of bottom sediment in the sea waters Punggur found more sand.Discrete-method result Beam Equi-Spaced unshaded Line Array discovered the sunken wreck. Keywords: Side Scan Sonar, Beam Pattern Discrete-Equi-Spaced Unshaded Line Array, Incidence angle, Directivity pattern

  14. TLD Postal service for quality audits of beams of Co-60 in reference conditions in Cuba; Servicio Postal TLD para auditorias de calidad de haces de Co-60 en condiciones de referencia en Cuba

    Energy Technology Data Exchange (ETDEWEB)

    Gutierrez L, S.; Walwyn S, G.; Alonso V, G. [CPHR, Calle 20 No. 4113 e/41 y 47, Playa, C.P. 11300, C. Habana (Cuba)]. e-mail: stefan@cphr.edu.cu

    2006-07-01

    Purpose: To describe the methodology and experience of the Secondary Laboratory of Dosimetric Calibration of Cuba in the establishment of the TLD Postal Service for quality audits of beams of Co-60 in reference conditions. Materials and methods: Through the Coordinated Project of Research (Contract 10794) its was bought 200 solid thermoluminescent detectors of LiF: Mg, Ti (TLD-100) in micro bars form with dimensions of 6 x 1 x 1 mm and of the JR 1152F type manufactured in China. All these detectors were identified individually with a serial number on one of its faces, using a graphite fine sheet. Those detectors for its irradiation are introduced in cylindrical plastic capsules developed and used by the International Atomic Energy Agency (IAEA) in the Audit Postal Service of Dose IAEA/WHO, the capsules have one cavity equal to 3 mm for that is necessary to recover this cavity with a fine plastic tube so that the detectors remain immobile during the irradiation. The method used to determine the individual sensitivity of the thermoluminescent detectors is: to irradiate a detectors group (100 micro bars) 4 times in those same geometric conditions, with the same irradiation history and reading, then it is determine for each detector a sensitivity factor equal to the average of those readings obtained for the 4 irradiation cycles for each i detector among the average of all the reading values obtained during the 4 cycles. The thermoluminescent signal is obtained with a Harshaw 2000C/B reader manual. Results: The satisfactory results obtained in the verification of the calibration of the TLD system, using the reference irradiation service of the Seibersdorf Dosimetry Laboratory of the IAEA in three different years are shown. The results of the audits carried out to the different radiotherapy services of the country in different years are also presented. Conclusions: The experience with the detectors acquired in the project demonstrates that with an appropriate

  15. Incident Information Management Tool

    CERN Document Server

    Pejovic, Vladimir

    2015-01-01

    Flaws of\tcurrent incident information management at CMS and CERN\tare discussed. A new data\tmodel for future incident database is\tproposed and briefly described. Recently developed draft version of GIS-­‐based tool for incident tracking is presented.

  16. Beam brilliance investigation of high current ion beams at GSI heavy ion accelerator facility.

    Science.gov (United States)

    Adonin, A A; Hollinger, R

    2014-02-01

    In this work the emittance measurements of high current Ta-beam provided by VARIS (Vacuum Arc Ion Source) ion source are presented. Beam brilliance as a function of beam aperture at various extraction conditions is investigated. Influence of electrostatic ion beam compression in post acceleration gap on the beam quality is discussed. Use of different extraction systems (single aperture, 7 holes, and 13 holes) in order to achieve more peaked beam core is considered. The possible ways to increase the beam brilliance are discussed.

  17. Risk - hazardous incident - communication 1

    International Nuclear Information System (INIS)

    Gerling, R.; Obermeier, O.P.

    1994-01-01

    Terms such as 'risk', 'hazardous incident', and 'communication' have become major catchwords in discussions about present-day problems, and may be reduced to a common denominator: disaster. Such an association, however, is inappropriate, as the concept indicated by the term 'risk' for instance covers a wide scale of possible danger. Even the term 'hazardous incident' describes events or conditions that are very different in terms of possible danger, let alone disastrous effects. The discrepancy to be observed between the facts and the public perception usually is due to the fact that people have little insight into the complex of problems involved, and to insufficient communication between the world of experts and the general public. The contributions to this publication present information and discuss a variety of solution sets to improve the communication problems in the context of the problem area of 'risk - hazardous incident - communication'. (orig./CB) [de

  18. Quantum beams

    International Nuclear Information System (INIS)

    Uesaka, Mitsuru

    2003-01-01

    Present state and future prospect are described on quantum beams for medical use. Efforts for compactness of linac for advanced cancer therapy have brought about the production of machines like Accuray's CyberKnife and TOMOTHERAPY (Tomo Therapy Inc.) where the acceleration frequency of X-band (9-11 GHz) is used. For cervical vein angiography by the X-band linac, a compact hard X-ray source is developed which is based on the (reverse) Compton scattering through laser-electron collision. More intense beam and laser are necessary at present. A compact machine generating the particle beam of 10 MeV-1 GeV (laser-plasma accelerator) for cancer therapy is also developed using the recent compression technique (chirped-pulse amplification) to generate laser of >10 TW. Tokyo University is studying for the electron beam with energy of GeV order, for the laser-based synchrotron X-ray, and for imaging by the short pulse ion beam. Development of advanced compact accelerators is globally attempted. In Japan, a virtual laboratory by National Institute of Radiological Sciences (NIRS), a working group of universities and research facilities through the Ministry of Education, Culture, Sports, Science and Technology, started in 2001 for practical manufacturing of the above-mentioned machines for cancer therapy and for angiography. Virtual Factory (Inc.), a business venture, is to be stood in future. (N.I.)

  19. Beam Angular Divergence Effects in Ion Implantation

    International Nuclear Information System (INIS)

    Horsky, T. N.; Hahto, S. K.; Bilbrough, D. G.; Jacobson, D. C.; Krull, W. A.; Goldberg, R. D.; Current, M. I.; Hamamoto, N.; Umisedo, S.

    2008-01-01

    An important difference between monomer ion beams and heavy molecular beams is a significant reduction in beam angular divergence and increased on-wafer angular accuracy for molecular beams. This advantage in beam quality stems from a reduction in space-charge effects within the beam. Such improved angular accuracy has been shown to have a significant impact on the quality and yield of transistor devices [1,12]. In this study, B 18 H x + beam current and angular divergence data collected on a hybrid scanned beam line that magnetically scans the beam across the wafer is presented. Angular divergence is kept below 0.5 deg from an effective boron energy of 200 eV to 3000 eV. Under these conditions, the beam current is shown analytically to be limited by space charge below about 1 keV, but by the matching of the beam emittance to the acceptance of the beam line above 1 keV. In addition, results of a beam transport model which includes variable space charge compensation are presented, in which a drift mode B 18 H x + beam is compared to an otherwise identical boron beam after deceleration. Deceleration is shown to introduce significant space-charge blow up resulting in a large on-wafer angular divergence. The divergence effects introduced by wafer charging are also discussed.

  20. Finite element modelling of composite castellated beam

    Directory of Open Access Journals (Sweden)

    Frans Richard

    2017-01-01

    Full Text Available Nowadays, castellated beam becomes popular in building structural as beam members. This is due to several advantages of castellated beam such as increased depth without any additional mass, passing the underfloor service ducts without changing of story elevation. However, the presence of holes can develop various local effects such as local buckling, lateral torsional buckling caused by compression force at the flange section of the steel beam. Many studies have investigated the failure mechanism of castellated beam and one technique which can prevent the beam fall into local failure is the use of reinforced concrete slab as lateral support on castellated beam, so called composite castellated beam. Besides of preventing the local failure of castellated beam, the concrete slab can increase the plasticity moment of the composite castellated beam section which can deliver into increasing the ultimate load of the beam. The aim of this numerical studies of composite castellated beam on certain loading condition (monotonic quasi-static loading. ABAQUS was used for finite element modelling purpose and compared with the experimental test for checking the reliability of the model. The result shows that the ultimate load of the composite castellated beam reached 6.24 times than the ultimate load of the solid I beam and 1.2 times compared the composite beam.

  1. Importance of beam-beam tune spread to collective beam-beam instability in hadron colliders

    International Nuclear Information System (INIS)

    Jin Lihui; Shi Jicong

    2004-01-01

    In hadron colliders, electron-beam compensation of beam-beam tune spread has been explored for a reduction of beam-beam effects. In this paper, effects of the tune-spread compensation on beam-beam instabilities were studied with a self-consistent beam-beam simulation in model lattices of Tevatron and Large Hodron Collider. It was found that the reduction of the tune spread with the electron-beam compensation could induce a coherent beam-beam instability. The merit of the compensation with different degrees of tune-spread reduction was evaluated based on beam-size growth. When two beams have a same betatron tune, the compensation could do more harm than good to the beams when only beam-beam effects are considered. If a tune split between two beams is large enough, the compensation with a small reduction of the tune spread could benefit beams as Landau damping suppresses the coherent beam-beam instability. The result indicates that nonlinear (nonintegrable) beam-beam effects could dominate beam dynamics and a reduction of beam-beam tune spread by introducing additional beam-beam interactions and reducing Landau damping may not improve the stability of beams

  2. Beam dynamics

    International Nuclear Information System (INIS)

    Abell, D; Adelmann, A; Amundson, J; Dragt, A; Mottershead, C; Neri, F; Pogorelov, I; Qiang, J; Ryne, R; Shalf, J; Siegerist, C; Spentzouris, P; Stern, E; Venturini, M; Walstrom, P

    2006-01-01

    We describe some of the accomplishments of the Beam Dynamics portion of the SciDAC Accelerator Science and Technology project. During the course of the project, our beam dynamics software has evolved from the era of different codes for each physical effect to the era of hybrid codes combining start-of-the-art implementations for multiple physical effects to the beginning of the era of true multi-physics frameworks. We describe some of the infrastructure that has been developed over the course of the project and advanced features of the most recent developments, the interplay betwen beam studies and simulations and applications to current machines at Fermilab. Finally we discuss current and future plans for simulations of the International Linear Collider

  3. Angular beam width of a slit-diffracted wave with noncollinear group and phase velocities

    International Nuclear Information System (INIS)

    Lock, Edwin H

    2012-01-01

    Taking magnetostatic surface wave diffraction as an example, this paper theoretically investigates the 2D diffraction pattern arising in the far-field region of a ferrite slab in the case of a plane wave with noncollinear group and phase velocities incident on a wide, arbitrarily oriented slit in an opaque screen. A universal analytical formula for the angular width of a diffracted beam is derived, which is valid for magnetostatic and other types of waves in anisotropic media and structures (including metamaterials) in 2D geometries. It is shown that the angular width of a diffracted beam in an anisotropic medium can not only take values greater or less than λ 0 /D (where λ 0 is the incident wavelength, and D is the slit width), but can also be zero under certain conditions. (methodological notes)

  4. Radiation and shielding around beam absorbers

    International Nuclear Information System (INIS)

    Hurkmans, A.; Maas, R.

    1978-12-01

    During operational conditions it is anticipated that a fair amount of the total available beam power is dumped in either the slit system on one of the beam dumps. Thses beam absorbers therefore become strong radioactive sources. The radiation level due to the absorption of a 100 kW electron beam is estimated and the problem of residual activity is treated. Proposed shielding materials are discussed. (C.F.)

  5. Electron beam-cured coating

    International Nuclear Information System (INIS)

    Kishi, Naoyuki

    1976-01-01

    The method for hardening coatings by the irradiation with electron beams is reviewed. The report is divided into seven parts, namely 1) general description and characteristics of electron beam-cured coating, 2) radiation sources of curing, 3) hardening conditions and reaction behaviour, 4) uses and advantages, 5) latest trends of the industry, 6) practice in the field of construction materials, and 7) economy. The primary characteristics of the electron beam hardening is that graft reaction takes place between base resin and coating to produce strong adhesive coating without any pretreatment. A variety of base resins are developed. High class esters of acrylic acid monomers and methacrylic acid monomers are mainly used as dilutants recently. At present, scanning type accelerators are used, but the practical application of the system producing electron beam of curtain type is expected. The dose rate dependence, the repetitive irradiation and the irradiation atmosphere are briefly described. The filed patent applications on the electron beam hardening were analyzed by the officer of Japan Patent Agency. The production lines for coatings by the electron beam hardening in the world are listed. In the electron beam-cured coating, fifty percent of given energy is consumed effectively for the electron beam hardening, and the solvents discharged from ovens and polluting atmosphere are not used, because the paints of high solid type is used. The running costs of the electron beam process are one sixth of the thermal oven process. (Iwakiri, K.)

  6. High-energy acceleration of an intense negative ion beam

    International Nuclear Information System (INIS)

    Takeiri, Y.; Ando, A.; Kaneko, O.

    1995-02-01

    A high-current H - ion beam has been accelerated with the two-stage acceleration. A large negative hydrogen ion source with an external magnetic filter produces more than 10 A of the H - ions from the grid area of 25cm x 50cm with the arc efficiency of 0.1 A/kW by seeding a small amount of cesium. The H - ion current increases according to the 3/2-power of the total beam energy. A 13.6 A of H - ion beam has been accelerated to 125 keV at the operational gas pressure of 3.4 mTorr. The optimum beam acceleration is achieved with nearly the same electric fields in the first and the second acceleration gaps on condition that the ratio of the first acceleration to the extraction electric fields is adjusted for an aspect ratio of the extraction gap. The ratio of the acceleration drain current to the H - ion current is more than 1.7. That is mainly due to the secondary electron generated by the incident H - ions on the extraction grid and the electron suppression grid. The neutralization efficiency was measured and agrees with the theoretical calculation result. (author)

  7. Ultra low-K shrinkage behavior when under electron beam in a scanning electron microscope

    Energy Technology Data Exchange (ETDEWEB)

    Lorut, F.; Imbert, G. [ST Microelectronics, 850 rue Jean Monnet, 38926 Crolles Cedex (France); Roggero, A. [Centre National d' Etudes Spatiales, 18 Avenue Edouard Belin, 31400 Toulouse (France)

    2013-08-28

    In this paper, we investigate the tendency of porous low-K dielectrics (also named Ultra Low-K, ULK) behavior to shrink when exposed to the electron beam of a scanning electron microscope. Various experimental electron beam conditions have been used for irradiating ULK thin films, and the resulting shrinkage has been measured through use of an atomic force microscope tool. We report the shrinkage to be a fast, cumulative, and dose dependent effect. Correlation of the shrinkage with incident electron beam energy loss has also been evidenced. The chemical modification of the ULK films within the interaction volume has been demonstrated, with a densification of the layer and a loss of carbon and hydrogen elements being observed.

  8. Incident spectrum determination for time-of-flight neutron powder diffraction data analysis

    International Nuclear Information System (INIS)

    Hodges, J. P.

    1998-01-01

    Accurate characterization of the incident neutron spectrum is an important requirement for precise Rietveld analysis of time-of-flight powder neutron diffraction data. Without an accurate incident spectrum the calculated model for the measured relative intensities of individual Bragg reflections will possess systematic errors. We describe a method for obtaining an accurate numerical incident spectrum using data from a transmitted beam monitor

  9. Laser Incident Lessons Learned and Action List

    Energy Technology Data Exchange (ETDEWEB)

    Yarotski, Dmitry Anatolievitch [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-02-29

    On Thursday November 19, 2015, LANL postdoc received an eye injury from a reflected, nonvisible laser beam (Class 4, pulsed, wavelength 800 nanometer). The setup is configured to split the laser output into two work areas in which qualified operators conduct research experiments. During this incident, the laser output beam was being projected to both experimental work areas, although only one experimental area was actively being used. The second laser beam directed to the second work area was blocked by an inappropriate device (Plexiglas, reflective, non-normal incidence) that reflected substantial portion of the beam toward the first setup. In preparation for the measurements, worker stepped on the stepstool and decided to remove the laser goggles to better see the micrometer readings which were difficult to see due to insufficient lighting. Immediately, he noticed a flash of light in his eye. The operator quickly replaced the laser eye-wear and then, using an infrared viewer, located a stray laser beam being reflected from the plexiglas beam block. The operator did not think he had sustained any injury and continued working. Later that day, however, he noticed a blurry spot in the vision of his left eye. He notified his supervisor on Friday morning, November 20, 2015, and was taken by CINT management to Sandia National Laboratories (SNL) medical facility for evaluation. SNL Medical did not find any abnormalities, but referred the operator to a local ophthalmologist for further evaluation. Further evaluations by the ophthalmologist on November 21 and November 23 identified a small spot of inflammation near the fovea on the retina in his left eye. The ophthalmologist stated that this spot would most likely heal on its own and that the blurry spot on the operator's vision would go away. A follow-up visit was scheduled. The employee was released back to work without restrictions.

  10. An introduction to beam physics

    CERN Document Server

    Berz, Martin; Wan, Weishi

    2015-01-01

    The field of beam physics touches many areas of physics, engineering, and the sciences. In general terms, beams describe ensembles of particles with initial conditions similar enough to be treated together as a group so that the motion is a weakly nonlinear perturbation of a chosen reference particle. Particle beams are used in a variety of areas, ranging from electron microscopes, particle spectrometers, medical radiation facilities, powerful light sources, and astrophysics to large synchrotrons and storage rings such as the LHC at CERN. An Introduction to Beam Physics is based on lectures given at Michigan State University’s Department of Physics and Astronomy, the online VUBeam program, the U.S. Particle Accelerator School, the CERN Academic Training Programme, and various other venues. It is accessible to beginning graduate and upper-division undergraduate students in physics, mathematics, and engineering. The book begins with a historical overview of methods for generating and accelerating beams, high...

  11. X-ray section topographs under various coherence properties of the primary beam

    International Nuclear Information System (INIS)

    Borowski, J.; Gronkowski, J.

    2001-01-01

    The aim of this work is to study to what extent a typical section-topography setup can supply information about the degree of coherence of the incident x-ray beam. In real experiments, the incident beam is partially coherent, with the degree of coherence described by the shape of the correlation function. In this paper the correlation functions for the outgoing beam are calculated by solving the Takagi-Taupin equations, assuming a truncated Gauss correlation function for the incident beam with the correlation length determined by the van Cittert-Zernike theorem. Its influence on the measured intensity of the diffracted beam in section topography is investigated. (author)

  12. Angularly symmetric splitting of a light beam upon reflection and refraction at an air-dielectric plane boundary: comment.

    Science.gov (United States)

    Andersen, Torben B

    2016-05-01

    In a recent paper, conditions for achieving equal and opposite angular deflections of a light beam by reflection and refraction at an interface between air and a dielectric were determined [J. Opt. Soc. Am. A32, 2436 (2015)JOAOD60740-323210.1364/JOSAA.32.002436]. The paper gives plots of angles of incidence and refraction as a function of the prism refractive index as well as plots of reflectances and incident linear-polarization azimuth angles as functions of the refractive index. We show here that it is possible to express these quantities as simple algebraic functions of the refractive index.

  13. Thermal self-focusing at oblique incidence

    International Nuclear Information System (INIS)

    Craxton, R.S.; McCrory, R.L.

    1984-03-01

    Thermal self-focusing at oblique incidence has been investigated in two-dimensional line-focus geometry using the Eulerian hydrodynamics simulation code SAGE. The laser beam interacts with a long-scale-length preformed plasma with an expontial density profiele. Questions to be addressed include: (1) What happens when a self-focusing channel reaches the turning point of the incident rays, and (2) Does the unabsorbed light return in the specular direction or back along the channel. A comparison is also made between thermal self-focusing at normal incidence in cylindrical and line-focus geometries: in cylindrical geometry the self-focusing mechanism is enhanced by the relative ease with which plasma may be expelled from a small cylindrical channel

  14. Influence of total beam current on HRTEM image resolution in differentially pumped ETEM with nitrogen gas

    International Nuclear Information System (INIS)

    Bright, A.N.; Yoshida, K.; Tanaka, N.

    2013-01-01

    Environmental transmission electron microscopy (ETEM) enables the study of catalytic and other reaction processes as they occur with Angstrom-level resolution. The microscope used is a dedicated ETEM (Titan ETEM, FEI Company) with a differential pumping vacuum system and apertures, allowing aberration corrected high-resolution transmission electron microscopy (HRTEM) imaging to be performed with gas pressures up to 20 mbar in the sample area and with significant advantages over membrane-type E-cell holders. The effect on image resolution of varying the nitrogen gas pressure, electron beam current density and total beam current were measured using information limit (Young's fringes) on a standard cross grating sample and from silicon crystal lattice imaging. As expected, increasing gas pressure causes a decrease in HRTEM image resolution. However, the total electron beam current also causes big changes in the image resolution (lower beam current giving better resolution), whereas varying the beam current density has almost no effect on resolution, a result that has not been reported previously. This behavior is seen even with zero-loss filtered imaging, which we believe shows that the drop in resolution is caused by elastic scattering at gas ions created by the incident electron beam. Suitable conditions for acquiring high resolution images in a gas environment are discussed. Lattice images at nitrogen pressures up to 16 mbar are shown, with 0.12 nm information transfer at 4 mbar. -- Highlights: ► ETEM images with point resolution of 0.12 nm in 4 mbar of nitrogen gas. ► Clear Si lattice imaging with 16 mbar of nitrogen gas. ► ETEM image resolution in gas can be much improved by decreasing total beam current. ► Beam current density (beam convergence) has no effect on the image resolution.

  15. Influence of total beam current on HRTEM image resolution in differentially pumped ETEM with nitrogen gas.

    Science.gov (United States)

    Bright, A N; Yoshida, K; Tanaka, N

    2013-01-01

    Environmental transmission electron microscopy (ETEM) enables the study of catalytic and other reaction processes as they occur with Angstrom-level resolution. The microscope used is a dedicated ETEM (Titan ETEM, FEI Company) with a differential pumping vacuum system and apertures, allowing aberration corrected high-resolution transmission electron microscopy (HRTEM) imaging to be performed with gas pressures up to 20 mbar in the sample area and with significant advantages over membrane-type E-cell holders. The effect on image resolution of varying the nitrogen gas pressure, electron beam current density and total beam current were measured using information limit (Young's fringes) on a standard cross grating sample and from silicon crystal lattice imaging. As expected, increasing gas pressure causes a decrease in HRTEM image resolution. However, the total electron beam current also causes big changes in the image resolution (lower beam current giving better resolution), whereas varying the beam current density has almost no effect on resolution, a result that has not been reported previously. This behavior is seen even with zero-loss filtered imaging, which we believe shows that the drop in resolution is caused by elastic scattering at gas ions created by the incident electron beam. Suitable conditions for acquiring high resolution images in a gas environment are discussed. Lattice images at nitrogen pressures up to 16 mbar are shown, with 0.12 nm information transfer at 4 mbar. Copyright © 2012 Elsevier B.V. All rights reserved.

  16. Beam transport

    International Nuclear Information System (INIS)

    1988-01-01

    The beam diagnostic components for both the transfer and the high-energy beamlines perform well except for some of the scanners whose noise pick-up has become a problem, especially at low beam intensities. This noise pick-up is primarily due to deterioration of the bearings in the scanner. At some locations in the high-energy beamlines, scanners were replaced by harps as the scanners proved to be practically useless for the low-intensity beams required in the experimental areas. The slits in the low-energy beamline, which are not water-cooled, have to be repaired at regular intervals because of vacuum leaks. Overheating causes the ceramic feedthroughs to deteriorate resulting in the vacuum leaks. Water-cooled slits have been ordered to replace the existing slits which will later be used in the beamlines associated with the second injector cyclotron SPC2. The current-measurement system will be slightly modified and should then be much more reliable. 3 figs

  17. Cancer incidence among waiters

    DEFF Research Database (Denmark)

    Reijula, Jere; Kjaerheim, Kristina; Lynge, Elsebeth

    2015-01-01

    AIMS: To study cancer risk patterns among waiters in the Nordic countries. METHODS: We identified a cohort of 16,134 male and 81,838 female waiters from Denmark, Finland, Iceland, Norway and Sweden. During the follow-up period from 1961 to 2005, we found that 19,388 incident cancer cases were...... diagnosed. Standardised incidence ratio (SIR) was defined as the observed number of cancer cases divided by the expected number, based on national age, time period and gender-specific cancer incidence rates in the general population. RESULTS: The SIR of all cancers in waiters, in the five countries combined...... INCIDENCE IN SOME CANCER SITES CAN LIKELY BE EXPLAINED BY HIGHER ALCOHOL CONSUMPTION, THE PREVALENCE OF SMOKING AND OCCUPATIONAL EXPOSURE TO TOBACCO SMOKE HOPEFULLY, THE INCIDENCE OF CANCER AMONG WAITERS WILL DECREASE IN THE FUTURE, DUE TO THE BANNING OF TOBACCO SMOKING IN RESTAURANTS AND BARS IN THE NORDIC...

  18. Experimental validation of the DPM Monte Carlo code using minimally scattered electron beams in heterogeneous media

    International Nuclear Information System (INIS)

    Chetty, Indrin J.; Moran, Jean M.; Nurushev, Teamor S.; McShan, Daniel L.; Fraass, Benedick A.; Wilderman, Scott J.; Bielajew, Alex F.

    2002-01-01

    A comprehensive set of measurements and calculations has been conducted to investigate the accuracy of the Dose Planning Method (DPM) Monte Carlo code for electron beam dose calculations in heterogeneous media. Measurements were made using 10 MeV and 50 MeV minimally scattered, uncollimated electron beams from a racetrack microtron. Source distributions for the Monte Carlo calculations were reconstructed from in-air ion chamber scans and then benchmarked against measurements in a homogeneous water phantom. The in-air spatial distributions were found to have FWHM of 4.7 cm and 1.3 cm, at 100 cm from the source, for the 10 MeV and 50 MeV beams respectively. Energy spectra for the electron beams were determined by simulating the components of the microtron treatment head using the code MCNP4B. Profile measurements were made using an ion chamber in a water phantom with slabs of lung or bone-equivalent materials submerged at various depths. DPM calculations are, on average, within 2% agreement with measurement for all geometries except for the 50 MeV incident on a 6 cm lung-equivalent slab. Measurements using approximately monoenergetic, 50 MeV, 'pencil-beam'-type electrons in heterogeneous media provide conditions for maximum electronic disequilibrium and hence present a stringent test of the code's electron transport physics; the agreement noted between calculation and measurement illustrates that the DPM code is capable of accurate dose calculation even under such conditions. (author)

  19. Radiological incidents in radiotherapy

    International Nuclear Information System (INIS)

    Hobzova, L.; Novotny, J.

    2008-01-01

    In many countries a reporting system of radiological incidents to national regulatory body exists and providers of radiotherapy treatment are obliged to report all major and/or in some countries all incidents occurring in institution. State Office for Nuclear Safety (SONS) is providing a systematic guidance for radiotherapy departments from 1997 by requiring inclusion of radiation safety problems into Quality assurance manual, which is the basic document for obtaining a license of SONS for handling with sources of ionizing radiation. For that purpose SONS also issued the recommendation 'Introduction of QA system for important sources in radiotherapy-radiological incidents' in which the radiological incidents are defined and the basic guidance for their classification (category A, B, C, D), investigation and reporting are given. At regular periods the SONS in co-operation with radiotherapy centers is making a survey of all radiological incidents occurring in institutions and it is presenting obtained information in synoptic communication (2003 Motolske dny, 2005 Novy Jicin). This presentation is another summary report of radiological incidents that occurred in our radiotherapy institutions during last 3 years. Emphasis is given not only to survey and statistics, but also to analysis of reasons of the radiological incidents and to their detection and prevention. Analyses of incidents in radiotherapy have led to a much broader understanding of incident causation. Information about the error should be shared as early as possible during or after investigation by all radiotherapy centers. Learning from incidents, errors and near misses should be a part of improvement of the QA system in institutions. Generally, it is recommended that all radiotherapy facilities should participate in the reporting, analyzing and learning system to facilitate the dissemination of knowledge throughout the whole country to prevent errors in radiotherapy.(authors)

  20. Atomic and molecular beams production and collimation

    CERN Document Server

    Lucas, Cyril Bernard

    2013-01-01

    Atomic and molecular beams are employed in physics and chemistry experiments and, to a lesser extent, in the biological sciences. These beams enable atoms to be studied under collision-free conditions and allow the study of their interaction with other atoms, charged particles, radiation, and surfaces. Atomic and Molecular Beams: Production and Collimation explores the latest techniques for producing a beam from any substance as well as from the dissociation of hydrogen, oxygen, nitrogen, and the halogens.The book not only provides the basic expressions essential to beam design but also offers

  1. Beam divergence scaling in neutral beam injectors

    International Nuclear Information System (INIS)

    Holmes, A.J.T.

    1976-01-01

    One of the main considerations in the design of neutral beam injectors is to monimize the divergence of the primary ion beam and hence maximize the beam transport and minimize the input of thermal gas. Experimental measurements of the divergence of a cylindrical ion beam are presented and these measurements are used to analyze the major components of ion beam divergence, namely: space charge expansion, gas-ion scattering, emittance and optical aberrations. The implication of these divergence components in the design of a neutral beam injector system is discussed and a method of maximizing the beam current is described for a given area of source plasma

  2. Exact suppression of depolarisation by beam-beam interaction in an electron ring

    International Nuclear Information System (INIS)

    Buon, J.

    1983-03-01

    It is shown that depolarisation due to beam-beam interaction can be exactly suppressed in an electron storage ring. The necessary ''spin matching'' conditions to be fulfilled are derived for a planar ring. They depend on the ring optics, assumed linear, but not on the features of the beam-beam force, like intensity and non-linearity. Extension to a ring equipped with 90 0 spin rotators is straightorward

  3. Thermal self-focusing with multiple beams

    International Nuclear Information System (INIS)

    Craxton, R.S.; McCrory, R.L.

    1986-07-01

    Self-focusing in underdense plasmas in the presence of overlapping beams is of interest for multibeam laser-irradiation systems. The hydrodynamics/ray-tracing simulation code SAGE is used to model thermal self-focusing in two-dimensional line-focus geometry with beams incident obliquely at different angles. The conjecture that multiple overlapping beams may suppress self-focusing is investigated for parameters appropriate to reactor-sized targets; in particular, the dependence upon intensity, scale length and pulse width is examined. While the full problem is three-dimensional, insight may be gained from two-dimensional simulations

  4. Dynamical chaos and beam-beam models

    International Nuclear Information System (INIS)

    Izrailev, F.M.

    1990-01-01

    Some aspects of the nonlinear dynamics of beam-beam interaction for simple one-dimensional and two-dimensional models of round and flat beams are discussed. The main attention is paid to the stochasticity threshold due to the overlapping of nonlinear resonances. The peculiarities of a round beam are investigated in view of using the round beams in storage rings to get high luminosity. 16 refs.; 7 figs

  5. High energy beam manufacturing technologies

    International Nuclear Information System (INIS)

    Geskin, E.S.; Leu, M.C.

    1989-01-01

    Technological progress continues to enable us to utilize ever widening ranges of physical and chemical conditions for material processing. The increasing cost of energy, raw materials and environmental control make implementation of advanced technologies inevitable. One of the principal avenues in the development of material processing is the increase of the intensity, accuracy, flexibility and stability of energy flow to the processing site. The use of different forms of energy beams is an effective way to meet these sometimes incompatible requirements. The first important technological applications of high energy beams were welding and flame cutting. Subsequently a number of different kinds of beams have been used to solve different problems of part geometry control and improvement of surface characteristics. Properties and applications of different specific beams were subjects of a number of fundamental studies. It is important now to develop a generic theory of beam based manufacturing. The creation of a theory dealing with general principles of beam generation and beam-material interaction will enhance manufacturing science as well as practice. For example, such a theory will provide a format approach for selection and integration of different kinds of beams for a particular application. And obviously, this theory will enable us to integrate the knowledge bases of different manufacturing technologies. The War of the Worlds by H. G. Wells, as well as a number of more technical, although less exciting, publications demonstrate both the feasibility and effectiveness of the generic approach to the description of beam oriented technology. Without any attempt to compete with Wells, we still hope that this volume will contribute to the creation of the theory of beam oriented manufacturing

  6. Neutron Beam Filters

    International Nuclear Information System (INIS)

    Adib, M.

    2011-01-01

    The purpose of filters is to transmit neutrons with selected energy, while remove unwanted ones from the incident neutron beam. This reduces the background, and the number of spurious. The types of commonly used now-a-day neutron filters and their properties are discussed in the present work. There are three major types of neutron filters. The first type is filter of selective thermal neutron. It transmits the main reflected neutrons from a crystal monochromate, while reject the higher order contaminations accompanying the main one. Beams coming from the moderator always contain unwanted radiation like fast neutrons and gamma-rays which contribute to experimental background and to the biological hazard potential. Such filter type is called filter of whole thermal neutron spectrum. The third filter type is it transmits neutrons with energies in the resonance energy range (En . 1 KeV). The main idea of such neutron filter technique is the use of large quantities of a certain material which have the deep interference minima in its total neutron cross-section. By transmitting reactor neutrons through bulk layer of such material, one can obtain the quasimonochromatic neutron lines instead of white reactor spectrum.

  7. Beam Measurements of a CLOUD (Cosmics Leaving OUtdoor Droplets) Chamber

    CERN Document Server

    Kirkby, Jasper

    2001-01-01

    A striking correlation has recently been observed between global cloud cover and the flux of incident cosmic rays. The effect of natural variations in the cosmic ray flux is large, causing estimated changes in the Earth's energy radiation balance that are comparable to those attributed to greenhouse gases from the burning of fossil fuels since the Industrial Revolution. However a direct link between cosmic rays and cloud formation has not been unambiguously established. We therefore propose to experimentally measure cloud (water droplet) formation under controlled conditions in a test beam at CERN with a CLOUD chamber, duplicating the conditions prevailing in the troposphere. These data, which have never been previously obtained, will allow a detailed understanding of the possible effects of cosmic rays on clouds and confirm, or otherwise, a direct link between cosmic rays, global cloud cover and the Earth's climate. The measurements will, in turn, allow more reliable calculations to be made of the residual e...

  8. The influence of beam divergence on ion-beam induced surface patterns

    International Nuclear Information System (INIS)

    Kree, R.; Yasseri, T.; Hartmann, A.K.

    2009-01-01

    We present a continuum theory and a Monte Carlo model of self-organized surface pattern formation by ion-beam sputtering including effects of beam profiles. Recently, it has turned out that such secondary ion-beam parameters may have a strong influence on the types of emerging patterns. We first discuss several cases, for which beam profiles lead to random parameters in the theory of pattern formation. Subsequently we study the evolution of the averaged height profile in continuum theory and find that the typical Bradley-Harper scenario of dependence of ripple patterns on the angle of incidence can be changed qualitatively. Beam profiles are implemented in Monte Carlo simulations, where we find generic effects on pattern formation. Finally, we demonstrate that realistic beam profiles, taken from experiments, may lead to qualitative changes of surface patterns.

  9. Effects of Process Conditions on the Mechanical Behavior of Aluminium Wrought Alloy EN AW-2219 (AlCu6Mn Additively Manufactured by Laser Beam Melting in Powder Bed

    Directory of Open Access Journals (Sweden)

    Michael Cornelius Hermann Karg

    2017-01-01

    Full Text Available Additive manufacturing is especially suitable for complex-shaped 3D parts with integrated and optimized functionality realized by filigree geometries. Such designs benefit from low safety factors in mechanical layout. This demands ductile materials that reduce stress peaks by predictable plastic deformation instead of failure. Al–Cu wrought alloys are established materials meeting this requirement. Additionally, they provide high specific strengths. As the designation “Wrought Alloys” implies, they are intended for manufacturing by hot or cold working. When cast or welded, they are prone to solidification cracks. Al–Si fillers can alleviate this, but impair ductility. Being closely related to welding, Laser Beam Melting in Powder Bed (LBM of Al–Cu wrought alloys like EN AW-2219 can be considered challenging. In LBM of aluminium alloys, only easily-weldable Al–Si casting alloys have succeeded commercially today. This article discusses the influences of boundary conditions during LBM of EN AW-2219 on sample porosity and tensile test results, supported by metallographic microsections and fractography. Load direction was varied relative to LBM build-up direction. T6 heat treatment was applied to half of the samples. Pronounced anisotropy was observed. Remarkably, elongation at break of T6 specimens loaded along the build-up direction exceeded the values from literature for conventionally manufactured EN AW-2219 by a factor of two.

  10. Beam propagation

    International Nuclear Information System (INIS)

    Hermansson, B.R.

    1989-01-01

    The main part of this thesis consists of 15 published papers, in which the numerical Beam Propagating Method (BPM) is investigated, verified and used in a number of applications. In the introduction a derivation of the nonlinear Schroedinger equation is presented to connect the beginning of the soliton papers with Maxwell's equations including a nonlinear polarization. This thesis focuses on the wide use of the BPM for numerical simulations of propagating light and particle beams through different types of structures such as waveguides, fibers, tapers, Y-junctions, laser arrays and crystalline solids. We verify the BPM in the above listed problems against other numerical methods for example the Finite-element Method, perturbation methods and Runge-Kutta integration. Further, the BPM is shown to be a simple and effective way to numerically set up the Green's function in matrix form for periodic structures. The Green's function matrix can then be diagonalized with matrix methods yielding the eigensolutions of the structure. The BPM inherent transverse periodicity can be untied, if desired, by for example including an absorptive refractive index at the computational window edges. The interaction of two first-order soliton pulses is strongly dependent on the phase relationship between the individual solitons. When optical phase shift keying is used in coherent one-carrier wavelength communication, the fiber attenuation will suppress or delay the nonlinear instability. (orig.)

  11. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  12. Detection systems for radioactive ion beams

    International Nuclear Information System (INIS)

    Savajols, H.

    2002-01-01

    Two main methods are used to produce radioactive ion beams: -) the ISOL method (isotope separation on-line) in which the stable beam interacts with a thick target, the reaction products diffuse outside the target and are transferred to a source where they are ionized, a mass separator and a post-accelerator drive the selected radioactive ions to the right energy; -) the in-flight fragmentation method in which the stable beam interacts with a thin target, the reaction products are emitted from the target with a restricted angular distribution and a velocity close to that of the incident beam, the experimenter has to take advantage from the reaction kinetics to get the right particle beam. Characteristic time is far longer with the ISOL method but the beam intensity is much better because of the use of a post-accelerator. In both cases, the beam intensity is lower by several orders of magnitude than in the case of a stable beam. This article presents all the constraints imposed by radioactive beams to the detection systems of the reaction products and gives new technical solutions according to the type of nuclear reaction studied. (A.C.)

  13. Police Incident Blotter (Archive)

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — The Police Blotter Archive contains crime incident data after it has been validated and processed to meet Uniform Crime Reporting (UCR) standards, published on a...

  14. 2011 Japanese Nuclear Incident

    Science.gov (United States)

    EPA’s RadNet system monitored the environmental radiation levels in the United States and parts of the Pacific following the Japanese Nuclear Incident. Learn about EPA’s response and view historical laboratory data and news releases.

  15. Prediction of Safety Incidents

    Data.gov (United States)

    National Aeronautics and Space Administration — Safety incidents, including injuries, property damage and mission failures, cost NASA and contractors thousands of dollars in direct and indirect costs. This project...

  16. Marine Animal Incident Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Large whale stranding, death, ship strike and entanglement incidents are all recorded to monitor the health of each population and track anthropogenic factors that...

  17. Acute incidents during anaesthesia

    African Journals Online (AJOL)

    management of acute incidents and the prevention of ... High or total (complete) spinal blocks in obstetric .... Pain and opioid analgesics lead to delayed ... Step up postoperative care and use ... recognise suprasternal and supraclavicular.

  18. Ga+ implantation in a PZT film during focused ion beam micro-machining

    International Nuclear Information System (INIS)

    Wollschlaeger, Nicole; Oesterle, Werner; Haeusler, Ines; Stewart, Mark

    2015-01-01

    The objective of the present work was to study the impact of Focused Ion Beam (FIB) machining parameters on the thickness of the damaged layer within a thin film PZT. Therefore, different Ga + - ion doses and ion energies were applied to a standard PZT film (80/20 lead zirconium titanate) under two beam incidence angles (90 and 1 ). The thicknesses of the corresponding Ga + -implanted layers were then determined by cross-sectional TEM in combination with energy dispersive spectroscopic (EDS) line-scans and correlated with polarisation hysteresis loops. The results show a decrease of Ga + -implanted layer thickness with decreasing inclination angle, whereas ion energy and ion dose could be correlated with gallium concentration in the implanted layers. Under the most unfavorable conditions the depth of the affected zone was 26 nm, it was only 2 nm for the most favorable conditions. (copyright 2015 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. Implosion of multilayered cylindrical targets driven by intense heavy ion beams.

    Science.gov (United States)

    Piriz, A R; Portugues, R F; Tahir, N A; Hoffmann, D H H

    2002-11-01

    An analytical model for the implosion of a multilayered cylindrical target driven by an intense heavy ion beam has been developed. The target is composed of a cylinder of frozen hydrogen or deuterium, which is enclosed in a thick shell of solid lead. This target has been designed for future high-energy-density matter experiments to be carried out at the Gesellschaft für Schwerionenforschung, Darmstadt. The model describes the implosion dynamics including the motion of the incident shock and the first reflected shock and allows for calculation of the physical conditions of the hydrogen at stagnation. The model predicts that the conditions of the compressed hydrogen are not sensitive to significant variations in target and beam parameters. These predictions are confirmed by one-dimensional numerical simulations and thus allow for a robust target design.

  20. Clinical implementation of MOSFET detectors for dosimetry in electron beams

    International Nuclear Information System (INIS)

    Bloemen-van Gurp, Esther J.; Minken, Andre W.H.; Mijnheer, Ben J.; Dehing-Oberye, Cary J.G.; Lambin, Philippe

    2006-01-01

    Background and purpose: To determine the factors converting the reading of a MOSFET detector placed on the patient's skin without additional build-up to the dose at the depth of dose maximum (D max ) and investigate their feasibility for in vivo dose measurements in electron beams. Materials and methods: Factors were determined to relate the reading of a MOSFET detector to D max for 4-15 MeV electron beams in reference conditions. The influence of variation in field size, SSD, angle and field shape on the MOSFET reading, obtained without additional build-up, was evaluated using 4, 8 and 15 MeV beams and compared to ionisation chamber data at the depth of dose maximum (z max ). Patient entrance in vivo measurements included 40 patients, mostly treated for breast tumours. The MOSFET reading, converted to D max , was compared to the dose prescribed at this depth. Results: The factors to convert MOSFET reading to D max vary between 1.33 and 1.20 for the 4 and 15 MeV beams, respectively. The SSD correction factor is approximately 8% for a change in SSD from 95 to 100 cm, and 2% for each 5-cm increment above 100 cm SSD. A correction for fields having sides smaller than 6 cm and for irregular field shape is also recommended. For fields up to 20 x 20 cm 2 and for oblique incidence up to 45 deg., a correction is not necessary. Patient measurements demonstrated deviations from the prescribed dose with a mean difference of -0.7% and a standard deviation of 2.9%. Conclusion: Performing dose measurements with MOSFET detectors placed on the patient's skin without additional build-up is a well suited technique for routine dose verification in electron beams, when applying the appropriate conversion and correction factors

  1. Production of ion beam by conical pinched electron beam diode

    International Nuclear Information System (INIS)

    Matsukawa, Y.; Nakagawa, Y.

    1982-01-01

    Some properties of the ion beam produced by pinched electron beam diode having conical shape electrodes and organic insulator anode was studied. Ion energy is about 200keV and the peak diode current is about 30 kA. At 11cm from the diode apex, not the geometrical focus point, concentrated ion beam was obtained. Its density is more than 500A/cm 2 . The mean ion current density within the radius of 1.6cm around the axis from conical diode is two or three times that from an usual pinched electron beam diode with flat parallel electrodes of same dimension and impedance under the same conditions. (author)

  2. The incidence of urea cycle disorders

    OpenAIRE

    Summar, Marshall L.; Koelker, Stefan; Freedenberg, Debra; Le Mons, Cynthia; Haberle, Johannes; Lee, Hye-Seung; Kirmse, Brian

    2013-01-01

    A key question for urea cycle disorders is their incidence. In the United States two UCDs argininosuccinic synthetase and lyase deficiency are currently detected by newborn screening. We used newborn screening data on over 6. million births and data from the large US and European longitudinal registries to determine how common these conditions are. The incidence for the United States is predicted to be 1 urea cycle disorder patient for every 35000 births presenting about 113 new patients per ...

  3. Development of disease animal models using proton beam

    International Nuclear Information System (INIS)

    Nam, K. H.; Kim, E. K.; Kim, H. R.; Seo, Y. W.

    2010-03-01

    To identify proper proton beam dose for mutant mouse development, total 7 times of proton beam were performed. There are too low incidence of mutation in pup mouse which were derived embryos radiated by 1Gy proton beam. Some mutation could be identified in pup mice which were derived embryos radiated by 1.5-2.5Gy proton beam. Mouse embryos irradiated with 1-10Gy of proton beam were inhibited in their in vitro development to 2 cell stage. There was no pups born from embryos which were irradiated with proton beam over 3 Gy. Early mouse development were greatly inhibited by proton beam irradiation of over 10Gy when cultured in vitro. In conclusion, it is efficient to irradiate mouse embryo with 1.5-2.5Gy of proton beam for development of mutant mice

  4. Study of the Hollow Waveguides Physical Parameters Determined the Beam Shape Conservation of the Delivered Radiation

    International Nuclear Information System (INIS)

    Ben-David, M.; Inberg, A.; Katzir, A.; Croitoru, N.

    1999-01-01

    The modification of the laser source beam quality is one of the important factors effect the delivery of laser radiation by a waveguide. In this paper the results of input radiation coupling, radius of bending, length, cross section diameter, waveguide internal wall roughness and coupling lens focal length influence on the beam shape delivered from the flexible hollow waveguides are presented. The conditions for which the beam shape is near to that of the source were found. A theoretical model for the radiation propagation gives quantitative representation of relation between attenuation, beam profile, divergence and above indicated parameters was developed. In this model was supposed that the guiding is produced by multiple incidences on a metal (silver) layer and a dielectric (silver iodine) over layer, by refraction and reflection. The propagation of the rays was calculated using the physical laws of the geometrical optics. For the scattering calculations a random distribution of roughness centers on dielectric layer surface was considered. It was also supposed that the value of the cross section internal diameter (ID=d) was much larger than the transmitted wavelength. The experimental results have shown that losses due to absorption of the propagated radiation in the guiding layers, mainly (AgI), generate satellites of the laser source delivered fundamental Gaussian beam. Increasing of the hollow waveguide internal diameter decreases the attenuation and increases the deviation of beam shape from Gaussian. Off center coupling produce decreasing of the fundamental mode height and generation of the coupled Gaussian beam satellites. The waveguide internal wall roughness produce losses of the coupled radiation and beam profile deviations from that of the laser source. A good correspondence between the theoretical and experimental results obtained

  5. Studies on laser beam propagation and stimulated scattering in multiple beam experiments

    International Nuclear Information System (INIS)

    Labaune, C.; Lewis, K.; Bandulet, H.; Lewis, K.; Depierreux, S.; Huller, S.; Masson-Laborde, P.E.; Pesme, D.; Riazuelo, G.

    2006-01-01

    The propagation and stimulated scattering of intense laser beams interacting with underdense plasmas are two important issues for inertial confinement fusion (ICF). The purpose of this work was to perform experiments under well-controlled interaction conditions and confront them with numerical simulations to test the physics included in the codes. Experimental diagnostics include time and space resolved images of incident and SBS light and of SBS-ion acoustic activity. New numerical diagnostics, including similar constraints as the experimental ones and the treatment of the propagation of the light between the emitting area and the detectors, have been developed. Particular care was put to include realistic plasma density and velocity profiles, as well as laser pulse shape in the simulations. In the experiments presented in this paper, the interaction beam was used with a random phase plate (RPP) to produce a statistical distribution of speckles in the focal volume. Stimulated Brillouin Scattering (SBS) was described using a decomposition of the spatial scales which provides a predictive modeling of SBS in an expanding mm-scale plasma. Spatial and temporal behavior of the SBS-ion acoustic waves was found to be in good agreement with the experimental ones for two laser intensities. (authors)

  6. A Refined Zigzag Beam Theory for Composite and Sandwich Beams

    Science.gov (United States)

    Tessler, Alexander; Sciuva, Marco Di; Gherlone, Marco

    2009-01-01

    A new refined theory for laminated composite and sandwich beams that contains the kinematics of the Timoshenko Beam Theory as a proper baseline subset is presented. This variationally consistent theory is derived from the virtual work principle and employs a novel piecewise linear zigzag function that provides a more realistic representation of the deformation states of transverse-shear flexible beams than other similar theories. This new zigzag function is unique in that it vanishes at the top and bottom bounding surfaces of a beam. The formulation does not enforce continuity of the transverse shear stress across the beam s cross-section, yet is robust. Two major shortcomings that are inherent in the previous zigzag theories, shear-force inconsistency and difficulties in simulating clamped boundary conditions, and that have greatly limited the utility of these previous theories are discussed in detail. An approach that has successfully resolved these shortcomings is presented herein. Exact solutions for simply supported and cantilevered beams subjected to static loads are derived and the improved modelling capability of the new zigzag beam theory is demonstrated. In particular, extensive results for thick beams with highly heterogeneous material lay-ups are discussed and compared with corresponding results obtained from elasticity solutions, two other zigzag theories, and high-fidelity finite element analyses. Comparisons with the baseline Timoshenko Beam Theory are also presented. The comparisons clearly show the improved accuracy of the new, refined zigzag theory presented herein over similar existing theories. This new theory can be readily extended to plate and shell structures, and should be useful for obtaining relatively low-cost, accurate estimates of structural response needed to design an important class of high-performance aerospace structures.

  7. Improvements in or relating to electron beam deflection arrangements

    International Nuclear Information System (INIS)

    Bull, E.W.

    1979-01-01

    This relates to the deflection of ribbon-like electron beams in X-ray tubes particularly in radiographic equipment. The X-ray tubes includes a source of a ribbon-shaped beam of electrons relatively narrow in a direction orthogonal to the direction of the beam and relatively wide in a second orthogonal direction. An elongated target projects X-rays about a chosen direction in response to the incident beam. There is a means (toroidal former, deflection coils or plates) for deflecting the electron beam to scan the region of incidence along the target and correction means for changing the shape of the electron beam depending on the deflection so that the region of incidence of the deflected beam remains a linear region substantially parallel to the region of incidence of the undeflected beam. The apparatus for this, and variations, are described. A medical radiography unit (computerise axial tomography) including the X-ray tube described is also detailed. (U.K.)

  8. Sea Kayaking Incidents in Norway 2000-2014: An Issue of Bad Weather or Poor Judgement?

    Science.gov (United States)

    Aadland, Eivind; Noer, Gunnar; Vikene, Odd Lennart

    2016-01-01

    The aims of this study were to analyse recreational sea kayaking and touring incidents in Norway with a specific focus on wind conditions and to elaborate on practical implications for the prevention of future incidents. We included 49 incidents reported by the media between 2000 and 2014. Incidents occurred in various wind conditions, but most…

  9. Using prepulsing: a useful way for increasing absorption efficiency of high intensity laser beam

    International Nuclear Information System (INIS)

    Peng Huimin; Zhang Guoping; Sheng Jiatian

    1990-01-01

    Using prepulse to irradiate target for increasing absorption efficiency of high intensity incident laser beam is considered and some theoretical simulations have been done. 1-D non-LTE radiative hydrodynamic code is used to simulate the interactions of laser beam with matter. A gaussian laser prepulse of wavelength 1.06 μm, FWHM 600 ps and peak intensity 1.5 x 10 12 W/cm 2 was used to irradiate 20 μm thick Au plate target, after 3ns a main gaussian pulse with wavelength 1.06 μm, FWHM 600 ps and peak intensity 3.0 x 10 14 W/cm 2 irradiated the expanding Au plasma. The responces of laser-produced plasma conditions are shown. By comparing with without prepulsing, under the condition of same main incident laser pulse, the absorption efficiency is increased from 0.36 to 0.60 and the laser-x-ray conversion efficiency is increased from 0.16 to 0.25. The electron temperature of hot plasma is also higher than without prepulsing, and the x-ray spectrum which is emitted from laser-produced hot plasma is harder and more intense than without prepulsing. The responces of laser-produced plasma for Fe target with prepulsing are shown as well. The conclusion is that using prepulsing is a useful way for getting high absorption laser beam

  10. Simple beam profile monitor

    Energy Technology Data Exchange (ETDEWEB)

    Gelbart, W.; Johnson, R. R.; Abeysekera, B. [ASD Inc. Garden Bay, BC (Canada); Best Theratronics Ltd Ottawa Ontario (Canada); PharmaSpect Ltd., Burnaby BC (Canada)

    2012-12-19

    An inexpensive beam profile monitor is based on the well proven rotating wire method. The monitor can display beam position and shape in real time for particle beams of most energies and beam currents up to 200{mu}A. Beam shape, position cross-section and other parameters are displayed on a computer screen.

  11. Crystalline beams

    International Nuclear Information System (INIS)

    Schiffer, J.P.

    1989-01-01

    Ions in a storage ring are confined to a mean orbit by focusing elements. To a first approximation these may be described by a constant harmonic restoring force: F = -Kr. If the particles in the frame moving along with the beam have small random thermal energies, then they will occupy a cylindrical volume around the mean orbit and the focusing force will be balanced by that from the mutual repulsion of the particles. Inside the cylinder only residual two-particle interactions will play a significant role and some form of ordering might be expected to take place. The results of some of the first MD calculations showed a surprising result: not only were the particles arranged in the form of a tube, but they formed well-defined layers: concentric shells, with the particles in each shell arranged in a hexagonal lattice that is characteristic of two-dimensional Coulomb systems. This paper discusses the condense layer structure

  12. Semi-analytical solution to arbitrarily shaped beam scattering

    Science.gov (United States)

    Wang, Wenjie; Zhang, Huayong; Sun, Yufa

    2017-07-01

    Based on the field expansions in terms of appropriate spherical vector wave functions and the method of moments scheme, an exact semi-analytical solution to the scattering of an arbitrarily shaped beam is given. For incidence of a Gaussian beam, zero-order Bessel beam and Hertzian electric dipole radiation, numerical results of the normalized differential scattering cross section are presented to a spheroid and a circular cylinder of finite length, and the scattering properties are analyzed concisely.

  13. Impact of beam angle choice on pencil beam scanning breath-hold proton therapy for lung lesions

    DEFF Research Database (Denmark)

    Gorgisyan, Jenny; Perrin, Rosalind; Lomax, Antony J

    2017-01-01

    INTRODUCTION: The breath-hold technique inter alia has been suggested to mitigate the detrimental effect of motion on pencil beam scanned (PBS) proton therapy dose distributions. The aim of this study was to evaluate the robustness of incident proton beam angles to day-to-day anatomical variation...

  14. Grazing Incidence Neutron Optics

    Science.gov (United States)

    Gubarev, Mikhail V. (Inventor); Ramsey, Brian D. (Inventor); Engelhaupt, Darell E. (Inventor)

    2013-01-01

    Neutron optics based on the two-reflection geometries are capable of controlling beams of long wavelength neutrons with low angular divergence. The preferred mirror fabrication technique is a replication process with electroform nickel replication process being preferable. In the preliminary demonstration test an electroform nickel optics gave the neutron current density gain at the focal spot of the mirror at least 8 for neutron wavelengths in the range from 6 to 20.ANG.. The replication techniques can be also be used to fabricate neutron beam controlling guides.

  15. Optical tractor Bessel polarized beams

    Science.gov (United States)

    Mitri, F. G.; Li, R. X.; Guo, L. X.; Ding, C. Y.

    2017-01-01

    Axial and transverse radiation force cross-sections of optical tractor Bessel polarized beams are theoretically investigated for a dielectric sphere with particular emphasis on the beam topological charge (or order), half-cone angle and polarization. The angular spectrum decomposition method (ASDM) is used to derive the non-paraxial electromagnetic (EM) field components of the Bessel beams. The multipole expansion method using vector spherical harmonics is utilized and appropriate beam-shape coefficients are derived in order to compute the radiation force cross-sections. The analysis has no limitation to a particular range of frequencies such that the Rayleigh, Mie or geometrical optics regimes can all be considered effectively using the present rigorous formalism. The focus of this investigation is to identify some of the tractor beam conditions so as to achieve retrograde motion of a dielectric sphere located arbitrarily in space. Numerical computations for the axial and transverse radiation force cross-sections are presented for linear, right-circular, radial, azimuthal and mixed polarizations of the individual plane waves forming the Bessel beams of zeroth- and first-order (with positive or negative helicity), respectively. As the sphere shifts off the beam's axis, the axial pulling (tractor) force is weakened. Moreover, the transverse radiation force cross-section field changes with the sphere's size factor ka (where k is the wavenumber and a is the sphere radius). Both stable and unstable equilibrium regions around the beam's axis are found, depending on the choice of ka and the half-cone angle α0. These results are particularly important in the development of emergent technologies for the photophoretic assembly of optically-engineered (meta)materials with designed properties using optical tractor (vortex) beams, particle manipulation, levitation and positioning, and other applications.

  16. Static and transient beam loading of a synchrotron

    International Nuclear Information System (INIS)

    Zhang, S.Y.; Weng, W.T.

    1992-01-01

    In a synchrotron, when the beam induced current is comparable to the driver current, the RF cavity is subjected to beam loading perturbation and corrective steps have to be implemented to regain beam stability. In this paper, the static and transient beam loading will be studied. We first discuss the static beam loading, which includes the cavity detuning condition, the stability condition, and the generator power dissipation. The beam current induced beam phase deviation is used as criterion to study the transient beam loading. The upgraded and the old AGS RF system parameters are used as an example to demonstrate how to choose cavity and generator parameters to satisfy the stability requirements under the beam loading. The dynamic models for the beam loading with beam control, and the beam loading with fast power amplifier feedback are presented and analyzed. It is shown that the beam phase and radial feedbacks alone are insufficient for the transient beam loading compensation, but the fast power amplifier feedback can provide effective correction on the beam loading. The limitation of the fast feedback and the beam loading with tuning and AVC loops are also discussed

  17. Beam-Beam Interaction Studies at LHC

    CERN Document Server

    Schaumann, Michaela; Alemany Fernandez, R

    2011-01-01

    The beam-beam force is one of the most important limiting factors in the performance of a collider, mainly in the delivered luminosity. Therefore, it is essential to measure the effects in LHC. Moreover, adequate understanding of LHC beam-beam interaction is of crucial importance in the design phases of the LHC luminosity upgrade. Due to the complexity of this topic the work presented in this thesis concentrates on the beam-beam tune shift and orbit effects. The study of the Linear Coherent Beam-Beam Parameter at the LHC has been determined with head-on collisions with small number of bunches at injection energy (450 GeV). For high bunch intensities the beam-beam force is strong enough to expect orbit effects if the two beams do not collide head-on but with a crossing angle or with a given offset. As a consequence the closed orbit changes. The closed orbit of an unperturbed machine with respect to a machine where the beam-beam force becomes more and more important has been studied and the results are as well ...

  18. Dissipative effects in the beam-beam interaction of intersecting storage rings

    International Nuclear Information System (INIS)

    Ford, J.; Vivaldi, F.

    1982-01-01

    This proposal seeks continuing support for an ongoing research investigation of various dynamical instabilities which arise in high energy intersecting storage rings due to the beam-beam interaction. Although the dissipative effect of radiation in beam-beam machines is anticipated to be a dominant feature affecting stability in the dynamics of colliding beams of heavy particles, almost nothing is known regarding the stability problem in many-dimensional dissipative systems. The work proposed here will extend the earlier computations on weak instabilities in many-dimensional beam-beam models to include the effect of dissipation. The object of this research is to obtain conditions for global beam stability over long time scales as a function of the machine parameters

  19. Design of the digitizing beam position limit detector

    International Nuclear Information System (INIS)

    Merl, R.

    1998-01-01

    The Digitizing Beam Position Limit Detector (DBPLD) is designed to identify and react to beam missteering conditions in the Advanced Photon Source (APS) storage ring. The high power of the insertion devices requires these missteering conditions to result in a beam abort in less than 2 milliseconds. Commercially available beam position monitors provide a voltage proportional to beam position immediately upstream and downstream of insertion devices. The DBPLD is a custom VME board that digitizes these voltages and interrupts the heartbeat of the APS machine protection system when the beam position exceeds its trip limits

  20. Method for controlling low-energy high current density electron beams

    International Nuclear Information System (INIS)

    Lee, J.N.; Oswald, R.B. Jr.

    1977-01-01

    A method and an apparatus for controlling the angle of incidence of low-energy, high current density electron beams are disclosed. The apparatus includes a current generating diode arrangement with a mesh anode for producing a drifting electron beam. An auxiliary grounded screen electrode is placed between the anode and a target for controlling the average angle of incidence of electrons in the drifting electron beam. According to the method of the present invention, movement of the auxiliary screen electrode relative to the target and the anode permits reliable and reproducible adjustment of the average angle of incidence of the electrons in low energy, high current density relativistic electron beams

  1. Proton beam monitor chamber calibration

    International Nuclear Information System (INIS)

    Gomà, C; Meer, D; Safai, S; Lorentini, S

    2014-01-01

    The first goal of this paper is to clarify the reference conditions for the reference dosimetry of clinical proton beams. A clear distinction is made between proton beam delivery systems which should be calibrated with a spread-out Bragg peak field and those that should be calibrated with a (pseudo-)monoenergetic proton beam. For the latter, this paper also compares two independent dosimetry techniques to calibrate the beam monitor chambers: absolute dosimetry (of the number of protons exiting the nozzle) with a Faraday cup and reference dosimetry (i.e. determination of the absorbed dose to water under IAEA TRS-398 reference conditions) with an ionization chamber. To compare the two techniques, Monte Carlo simulations were performed to convert dose-to-water to proton fluence. A good agreement was found between the Faraday cup technique and the reference dosimetry with a plane-parallel ionization chamber. The differences—of the order of 3%—were found to be within the uncertainty of the comparison. For cylindrical ionization chambers, however, the agreement was only possible when positioning the effective point of measurement of the chamber at the reference measurement depth—i.e. not complying with IAEA TRS-398 recommendations. In conclusion, for cylindrical ionization chambers, IAEA TRS-398 reference conditions for monoenergetic proton beams led to a systematic error in the determination of the absorbed dose to water, especially relevant for low-energy proton beams. To overcome this problem, the effective point of measurement of cylindrical ionization chambers should be taken into account when positioning the reference point of the chamber. Within the current IAEA TRS-398 recommendations, it seems advisable to use plane-parallel ionization chambers—rather than cylindrical chambers—for the reference dosimetry of pseudo-monoenergetic proton beams. (paper)

  2. The beam transport system

    International Nuclear Information System (INIS)

    1986-01-01

    The first proton beams have been transported along the transfer beamline and the diagnostic components have thus been used and tested under real operating conditions. The various electronic systems have been linked to the control system and the equipment can now be operated from the control console. The performance of the diagnostic system for the transfer beamline is satisfactory. The beam diagnostic components for the high-energy beamlines up to the isotope production and neutron therapy vaults and the first experimental target rooms have been installed. The high-energy slits have been delivered. The scanner and harp electronics have been installed and linked to their respective components in the beamlines. The pneumatic acuator control electronics has been manufactured, installed and is operational; provision has been made for special control features of the equipment in the therapy beamline. The high-voltage bias supply for the Faraday cups has been implemented. The installation of the beam current measurement system is nearing completion although part of it is already operational. A coaxial relay multiplexer for the capacitive phase probe signals has been manufactured and installed. The diagnostic equipment for the beamlines to isotope production and neutron therapy is thus ready for operation. 4 figs

  3. Beam halo in high-intensity beams

    International Nuclear Information System (INIS)

    Wangler, T.P.

    1993-01-01

    In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which in projection to the 2-D phase spaces results in a 2-component beam consisting of an inner core and a diffuse outer halo. The beam-halo is of concern for a next generation of cw, high-power proton linacs that could be applied to intense neutron generators for nuclear materials processing. The author describes what has been learned about beam halo and the evolution of space-charge dominated beams using numerical simulations of initial laminar beams in uniform linear focusing channels. Initial results are presented from a study of beam entropy for an intense space-charge dominated beam

  4. Beam-beam issues in asymmetric colliders

    International Nuclear Information System (INIS)

    Furman, M.A.

    1992-07-01

    We discuss generic beam-beam issues for proposed asymmetric e + - e - colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II)

  5. Thrust generation experiments on microwave rocket with a beam concentrator for long distance wireless power feeding

    Science.gov (United States)

    Fukunari, Masafumi; Yamaguchi, Toshikazu; Nakamura, Yusuke; Komurasaki, Kimiya; Oda, Yasuhisa; Kajiwara, Ken; Takahashi, Koji; Sakamoto, Keishi

    2018-04-01

    Experiments using a 1 MW-class gyrotron were conducted to examine a beamed energy propulsion rocket, a microwave rocket with a beam concentrator for long-distance wireless power feeding. The incident beam is transmitted from a beam transmission mirror system. The beam transmission mirror system expands the incident beam diameter to 240 mm to extend the Rayleigh length. The beam concentrator receives the beam and guides it into a 56-mm-diameter cylindrical thruster tube. Plasma ignition and ionization front propagation in the thruster were observed through an acrylic window using a fast-framing camera. Atmospheric air was used as a propellant. Thrust generation was achieved with the beam concentrator. The maximum thrust impulse was estimated as 71 mN s/pulse from a pressure history at the thrust wall at the input energy of 638 J/pulse. The corresponding momentum coupling coefficient, Cm was inferred as 204 N/MW.

  6. Studies on normal incidence backscattering in nodule areas using the multibeam-hydrosweep system

    Digital Repository Service at National Institute of Oceanography (India)

    Pathak, D.; Chakraborty, B.

    The acoustic response from areas of varying nodule abundance and number densities in the Central Indian Ocean has been studied by using the echo peak amplitudes of the normal incidence beam in the Multibeam Hydrosweep system. It is observed...

  7. Proton Beam Writing

    International Nuclear Information System (INIS)

    Rajta, I.; Szilasi, S.Z.; Csige, I.; Baradacs, E.

    2005-01-01

    flow channel, which were also implanted at the same irradiation. During the porous Si formation we developed the sample 6-8 μm deeper than the implanting ion range damaged the crystal. Due to the isotropic nature of the porous Si etching, the thick sidewall blocks are still connected to the crystal while the thin membranes detached from the bottom, and they are only connected to one of the sidewalls. The other construction utilized the goniometer facility mounted on the microbeam chamber, we implanted the samples at 40 degrees tilt, and developed the samples not as deep as the ion range. This way both the sidewalls and the membranes are attached to the bottom of the sample. The SEM images of the samples showed that both of these types of valves can be actively working, however, the thickness of the moving membrane requires extremely large force according to the fluidic tests. In order to achieve a successful demonstration of the functionality, the membrane rigidity should be reduced by decreasing the wall thickness. Reduction of optimal fluence by CO 2 treatment after exposure and vacuum effects in proton beam micromachining of CR-39 CR-39 has been shown to be a suitable material as a thick resist for Proton Beam Writing [5]. These samples are normally used to detect single alpha particles in normal air conditions. However, to use this material as proton or alpha micromachinable resists, we need to irradiate the samples in vacuum. In this work, we investigated the effects of vacuum on the micromachinable properties of CR-39. Our investigations proved that there were no drawbacks of the vacuum storage of the samples, so we concluded that CR-39 is a suitable material as a PBM resist in this respect, too. Another part of the current work concentrated on the effect of post-irradiaton CO 2 treatment of the samples. Such a treatment increased the radiation sensitivity of CR-39, i.e. decreased the necessary optimal ion fluence. We have found that approximately 60% of fluence

  8. Hazmat Yearly Incident Summary Reports

    Data.gov (United States)

    Department of Transportation — Series of Incident data and summary statistics reports produced which provide statistical information on incidents by type, year, geographical location, and others....

  9. Radiation incidents in dentistry

    International Nuclear Information System (INIS)

    Lovelock, D.J.

    1996-01-01

    Most dental practitioners act as their own radiographer and radiologist, unlike their medical colleagues. Virtually all dental surgeons have a dental X-ray machine for intraoral radiography available to them and 40% of dental practices have equipment for dental panoramic tomography. Because of the low energy of X-ray equipment used in dentistry, radiation incidents tend to be less serious than those associated with other aspects of patient care. Details of 47 known incidents are given. The advent of the 1985 and 1988 Ionising Radiation Regulations has made dental surgeons more aware of the hazards of radiation. These regulations, and general health and safety legislation, have led to a few dental surgeons facing legal action. Because of the publicity associated with these court cases, it is expected that there will be a decrease in radiation incidents arising from the practice of dentistry. (author)

  10. Physics with polarized electron beams

    International Nuclear Information System (INIS)

    Swartz, M.L.

    1988-01-01

    As a distinct field, elementary particle physics is now approximately forty years old. In all that time, only a few of the thousands of experiments that have been performed have made use of spin polarized particle beams (with apologies to those who have studied neutrino interactions, polarized beam are defined to refer to the case in which the experimenter has control over the polarization direction). If the discussion is restricted to spin polarized electron beams, the number of experiments becomes countable with the fingers of one hand (with several to spare). There are two reasons for this lack of interest. The first is that spin polarized beams are difficult to produce, accelerate, and transport. The second reason is that any physical process that can occur during the collision of a polarized particle with another (polarized or not) can also occur during the collision of unpolarized particles. One might ask then, why has any effort been expended on the subject. The answer, at least in the case of polarized electron beams, is that electron accelerators and storage rings have in recent years achieved sufficient energy to begin to probe the weak interaction directly. The weak interaction distinguishes between left- and right-handed fermionic currents. Left-handed particles interact in a fundamentally different way than their right-handed counterparts. If the experimenter wishes to explore or exploit this difference, he (or she) must either prepare the spin state of the incident particles or analyze the spin state of outgoing particles. For reasons of genearlity and improved statistical precision, the former is usually preferable to the latter. The first of these lectures will review some of the techniques necessary for the production, transport, and monitoring of polarized electron (or positron) beams. The second lecture will survey some of the physics possibilities of polarized electron-positron collisions

  11. Monitor tables for electron beams in radiotherapy

    International Nuclear Information System (INIS)

    Christ, G.; Dohm, O.S.

    2007-01-01

    The application of electron beams in radiotherapy is still based on tables of monitor units, although 3-D treatment planning systems for electron beams are available. This have several reasons: The need for 3-D treatment planning is not recognized; there is no confidence in the calculation algorithm; Monte-Carlo algorithms are too time-consuming; and the effort necessary to measure basic beam data for 3-D planning is considered disproportionate. However, the increasing clinical need for higher dosimetric precision and for more conformal electron beams leads to the requirement for more sophisticated tables of monitor units. The present paper summarizes and discusses the main aspects concerning the preparation of tables of monitor units for electron beams. The measurement equipment and procedures for measuring basic beam data needed for tables of monitor units for electron beams are described for a standard radiation therapy linac. The design of tables of monitor units for standard electron applicators is presented; this design can be extended for individual electron inserts, to variable applicator surface distances, to oblique beam incidence, and the use of bolus material. Typical data of an Elekta linac are presented in various tables. (orig.)

  12. Beam test of CSES silicon strip detector module

    Science.gov (United States)

    Zhang, Da-Li; Lu, Hong; Wang, Huan-Yu; Li, Xin-Qiao; Xu, Yan-Bing; An, Zheng-Hua; Yu, Xiao-xia; Wang, Hui; Shi, Feng; Wang, Ping; Zhao, Xiao-Yun

    2017-05-01

    The silicon-strip tracker of the China Seismo-Electromagnetic Satellite (CSES) consists of two double-sided silicon strip detectors (DSSDs) which provide incident particle tracking information. A low-noise analog ASIC VA140 was used in this study for DSSD signal readout. A beam test on the DSSD module was performed at the Beijing Test Beam Facility of the Beijing Electron Positron Collider (BEPC) using a 400-800 MeV/c proton beam. The pedestal analysis results, RMSE noise, gain correction, and intensity distribution of incident particles of the DSSD module are presented. Supported by the XXX Civil Space Programme

  13. Underling modification in ion beam induced Si wafers

    International Nuclear Information System (INIS)

    Hazra, S.; Chini, T.K.; Sanyal, M.K.; Grenzer, J.; Pietsch, U.

    2005-01-01

    Subsurface (amorphous-crystalline interface) structure of keV ion beam modified Si(001) wafers was studied for the first time using non-destructive technique and compared with that of the top one. Ion-beam modifications of the Si samples were done using state-of-art high-current ion implanter facility at Saha Institute of Nuclear Physics by changing energy, dose and angle of incidence of the Ar + ion beam. To bring out the underlying modification depth-resolved x-ray grazing incidence diffraction has been carried out using synchrotron radiation facility, while the structure of the top surface was studied through atomic force microscopy

  14. Radiation produced by electrons incident on molecules

    International Nuclear Information System (INIS)

    Moehlman, G.R.

    1977-01-01

    The work described in this thesis deals with light intensity measurements of emission spectra (1850-9000 A) produced by a continuous or pulsed beam of monoenergetic electrons (0 - 2000 eV) incident on a variety of molecular gases like H 2 , D 2 , H 2 O, HCl, NH 3 and several hydrocarbons. The emission spectra are dominated by fluorescence from excited fragments produced via dissociative excitation, besides fluorescence from excited parent molecules themselves. The experimental results thus obtained are expressed in terms of emission cross sections and lifetimes

  15. Consideration of fluctuation in secondary beam intensity of heavy ion beam probe measurements

    Energy Technology Data Exchange (ETDEWEB)

    Fujisawa, A.; Iguchi, H.; Lee, S.; Hamada, Y.

    1997-01-01

    Heavy ion beam probes have capability to detect local electron density fluctuation in the interior of plasmas through the detected beam intensity fluctuation. However, the intensity fluctuation should suffer a certain degree of distortion from electron density and temperature fluctuations on the beam orbits, and as a result the signal can be quite different from the local density fluctuation. This paper will present a condition that the intensity fluctuation can be regarded as being purely local electron density fluctuation, together with discussion about the contamination of the fluctuation along the beam orbits to the beam intensity fluctuation. (author)

  16. Acoustic beam splitting in a sonic crystal around a directional band gap

    International Nuclear Information System (INIS)

    Cicek Ahmet; Kaya Olgun Adem; Ulug Bulent

    2013-01-01

    Beam splitting upon refraction in a triangular sonic crystal composed of aluminum cylinders in air is experimentally and numerically demonstrated to occur due to finite source size, which facilitates circumvention of a directional band gap. Experiments reveal that two distinct beams emerge at crystal output, in agreement with the numerical results obtained through the finite-element method. Beam splitting occurs at sufficiently-small source sizes comparable to lattice periodicity determined by the spatial gap width in reciprocal space. Split beams propagate in equal amplitude, whereas beam splitting is destructed for oblique incidence above a critical incidence angle

  17. Neutral beam data systems at ORNL

    International Nuclear Information System (INIS)

    Stewart, C.R.

    1982-01-01

    A control system for neutral injection beam lines has been designed, implemented, and used with much success. Despite the problems with very high power levels this system is very successful in relieving the operators burdens of slow conditioning, data recording, and mode switching. The use of computer control with multiple beam lines now appears very promising

  18. Properties of the accelerator-produced beam

    International Nuclear Information System (INIS)

    Caporaso, G.J.; Chambers, F.W.; Cole, A.G.; Fawley, W.M.; Struve, K.W.

    1985-01-01

    Obtaining detailed knowledge of the condition of the electron beam delivered to the experimental tank is of prime importance in the attempt to correlate the propagation data with theory. There are many interesting and unique features of the beam delivered by Advanced Test Accelerator (ATA) to the experimental tank

  19. Lightning incidents in Mongolia

    Directory of Open Access Journals (Sweden)

    Myagmar Doljinsuren

    2015-11-01

    Full Text Available This is one of the first studies that has been conducted in Mongolia on the distribution of lightning incidents. The study covers a 10-year period from 2004 to 2013. The country records a human death rate of 15.4 deaths per 10 million people per year, which is much higher than that of many countries with similar isokeraunic level. The reason may be the low-grown vegetation observed in most rural areas of Mongolia, a surface topography, typical to steppe climate. We suggest modifications to Gomes–Kadir equation for such countries, as it predicts a much lower annual death rate for Mongolia. The lightning incidents spread over the period from May to August with the peak of the number of incidents occurring in July. The worst lightning affected region in the country is the central part. Compared with impacts of other convective disasters such as squalls, thunderstorms and hail, lightning stands as the second highest in the number of incidents, human deaths and animal deaths. Economic losses due to lightning is only about 1% of the total losses due to the four extreme weather phenomena. However, unless precautionary measures are not promoted among the public, this figure of losses may significantly increase with time as the country is undergoing rapid industrialization at present.

  20. Incident users of antipsychotics

    DEFF Research Database (Denmark)

    Baandrup, Lone; Kruse, Marie

    2016-01-01

    PURPOSE: In Denmark, as well as in many other countries, consumption of antipsychotics is on the rise, partly due to increasing off-label use. The aim of this study was to analyze and quantify the extent of off-label use and polypharmacy in incident users of antipsychotic medication, and to examine...

  1. Response of the 'patient dose calibrator' chamber for incident positions and sizes of X-ray fields

    International Nuclear Information System (INIS)

    Oliveira, Cassio M.; Abrantes, Marcos Eugenio S.; Ferreira, Flavia C. Bastos; Lacerda, Marco A. de Souza; Alonso, Thessa C.; Silva, Teogenes A. da; Oliveira, Paulo Marcio C.

    2009-01-01

    The evaluation of patient doses is an important tool for optimizing radiodiagnostic medical procedures with conventional X-ray equipment and for improving the quality of the radiographic image. The Patient Dose Calibrator (PDC) chamber is a dosimetric instrument that is used in the evaluation of the air kerma-area product (P KA ) quantity aiming the reduction of patient doses. The objective this work was to study the P KA variation caused by different field incident positions and sizes of the X-ray beam on the PDC chamber. Results showed that the PDC chamber has repeatability lower than 0.6%, beam position dependence of 3% and linearity response within ± 6%; these characteristics are to be taken into account during evaluation of the radiological protection conditions of conventional x-ray equipment. (author)

  2. A symplectic coherent beam-beam model

    International Nuclear Information System (INIS)

    Furman, M.A.

    1989-05-01

    We consider a simple one-dimensional model to study the effects of the beam-beam force on the coherent dynamics of colliding beams. The key ingredient is a linearized beam-beam kick. We study only the quadrupole modes, with the dynamical variables being the 2nd-order moments of the canonical variables q, p. Our model is self-consistent in the sense that no higher order moments are generated by the linearized beam-beam kicks, and that the only source of violation of symplecticity is the radiation. We discuss the round beam case only, in which vertical and horizontal quantities are assumed to be equal (though they may be different in the two beams). Depending on the values of the tune and beam intensity, we observe steady states in which otherwise identical bunches have sizes that are equal, or unequal, or periodic, or behave chaotically from turn to turn. Possible implications of luminosity saturation with increasing beam intensity are discussed. Finally, we present some preliminary applications to an asymmetric collider. 8 refs., 8 figs

  3. Antihydrogen Beams

    Science.gov (United States)

    Yamazaki, Yasunori; Doser, Michael; Pérez, Patrice

    2018-03-01

    Why does our universe consist purely of matter, even though the same amount of antimatter and matter should have been produced at the moment of the Big Bang 13.8 billion years ago? One of the most potentially fruitful approaches to address the mystery is to study the properties of antihydrogen and antiprotons. Because they are both stable, we can in principle make measurement precision as high as we need to see differences between these antimatter systems and their matter counterparts, i.e. hydrogen and protons. This is the goal of cold antihydrogen research. To study a fundamental symmetry-charge, parity, and time reversal (CPT) symmetry-which should lead to identical spectra in hydrogen and antihydrogen, as well as the weak equivalence principle (WEP), cold antihydrogen research seeks any discrepancies between matter and antimatter, which might also offer clues to the missing antimatter mystery. Precision tests of CPT have already been carried out in other systems, but antihydrogen spectroscopy offers the hope of reaching even higher sensitivity to violations of CPT. Meanwhile, utilizing the Earth and antihydrogen atoms as an experimental system, the WEP predicts a gravitational interaction between matter and antimatter that is identical to that between any two matter objects. The WEP has been tested to very high precision for a range of material compositions, but no such precision test using antimatter has yet been carried out, offering hope of a telltale inconsistency between matter and antimatter. In this Discovery book, we invite you to visit the frontiers of cold antimatter research, focusing on new technologies to form beams of antihydrogen atoms and antihydrogen ions, and new ways of interrogating the properties of antimatter.

  4. Beam Techniques - Beam Control and Manipulation

    International Nuclear Information System (INIS)

    Minty, Michiko G

    2003-01-01

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization

  5. Beam Techniques - Beam Control and Manipulation

    Energy Technology Data Exchange (ETDEWEB)

    Minty, Michiko G

    2003-04-24

    We describe commonly used strategies for the control of charged particle beams and the manipulation of their properties. Emphasis is placed on relativistic beams in linear accelerators and storage rings. After a brief review of linear optics, we discuss basic and advanced beam control techniques, such as transverse and longitudinal lattice diagnostics, matching, orbit correction and steering, beam-based alignment, and linac emittance preservation. A variety of methods for the manipulation of particle beam properties are also presented, for instance, bunch length and energy compression, bunch rotation, changes to the damping partition number, and beam collimation. The different procedures are illustrated by examples from various accelerators. Special topics include injection and extraction methods, beam cooling, spin transport and polarization.

  6. Literature in Focus Beta Beams: Neutrino Beams

    CERN Document Server

    2009-01-01

    By Mats Lindroos (CERN) and Mauro Mezzetto (INFN Padova, Italy) Imperial Press, 2009 The beta-beam concept for the generation of electron neutrino beams was first proposed by Piero Zucchelli in 2002. The idea created quite a stir, challenging the idea that intense neutrino beams only could be produced from the decay of pions or muons in classical neutrino beams facilities or in future neutrino factories. The concept initially struggled to make an impact but the hard work by many machine physicists, phenomenologists and theoreticians over the last five years has won the beta-beam a well-earned position as one of the frontrunners for a possible future world laboratory for high intensity neutrino oscillation physics. This is the first complete monograph on the beta-beam concept. The book describes both technical aspects and experimental aspects of the beta-beam, providing students and scientists with an insight into the possibilities o...

  7. Diverse topics in crystalline beams

    International Nuclear Information System (INIS)

    Wei, Jie; Draeseke, A.; Sessler, A.M.; Li, Xiao-Ping

    1995-01-01

    Equations of motion are presented, appropriate to interacting charged particles of diverse charge and mass, subject to the external forces produced by various kinds of magnetic fields and radio-frequency (rf) electric fields in storage rings. These equations are employed in the molecular dynamics simulations to study the properties of crystalline beams. The two necessary conditions for the formation and maintenance of crystalline beams are summarized. The transition from ID to 2D, and from 2D to 3D is explored, and the scaling behavior of the heating rates is discussed especially in the high temperature limit. The effectiveness of various cooling techniques in achieving crystalline states has been investigated. Crystalline beams made of two different species of ions via sympathetic cooling are presented, as well as circulating ''crystal balls'' bunched in all directions by magnetic focusing and rf field. By numerically reconstructing the original experimental conditions of the NAP-M ring, it is found that only at extremely low beam intensities, outside of the range of the original measurement, proton particles can form occasionally-passing disks. The proposed New ASTRID ring is shown to be suitable for the formation and maintenance of crystalline beams of all dimensions

  8. Soviet exoatmospheric neutral particle beam research

    International Nuclear Information System (INIS)

    Leiss, J.E.; Abrams, R.H.; Ehlers, K.W.; Farrell, J.A.; Gillespie, G.H.; Jameson, R.A.; Keefe, D.; Parker, R.K.

    1988-02-01

    This technical assessment was performed by a panel of eight U.S. scientists and engineers who are familiar with Soviet research through their own research experience, their knowledge of the published scientific literature and conference proceedings, and personal contacts with Soviet scientists and other foreign colleagues. Most of the technical components of a neutral particle beam generating system including the ion source, the accelerator, the accelerator radio frequency power supply, the beam conditioning and aiming system, and the beam neutralizer system are addressed. It does not address a number of other areas important to an exoatmospheric neutral beam system

  9. Neutral helium beam probe

    Science.gov (United States)

    Karim, Rezwanul

    1999-10-01

    This article discusses the development of a code where diagnostic neutral helium beam can be used as a probe. The code solves numerically the evolution of the population densities of helium atoms at their several different energy levels as the beam propagates through the plasma. The collisional radiative model has been utilized in this numerical calculation. The spatial dependence of the metastable states of neutral helium atom, as obtained in this numerical analysis, offers a possible diagnostic tool for tokamak plasma. The spatial evolution for several hypothetical plasma conditions was tested. Simulation routines were also run with the plasma parameters (density and temperature profiles) similar to a shot in the Princeton beta experiment modified (PBX-M) tokamak and a shot in Tokamak Fusion Test Reactor tokamak. A comparison between the simulation result and the experimentally obtained data (for each of these two shots) is presented. A good correlation in such comparisons for a number of such shots can establish the accurateness and usefulness of this probe. The result can possibly be extended for other plasma machines and for various plasma conditions in those machines.

  10. Incidents with hazardous radiation sources

    International Nuclear Information System (INIS)

    Schoenhacker, Stefan

    2016-01-01

    Incidents with hazardous radiation sources can occur in any country, even those without nuclear facilities. Preparedness for such incidents is supposed to fulfill globally agreed minimum standards. Incidents are categorized in incidents with licensed handling of radiation sources as for material testing, transport accidents of hazardous radiation sources, incidents with radionuclide batteries, incidents with satellites containing radioactive inventory, incidents wit not licensed handling of illegally acquired hazardous radiation sources. The emergency planning in Austria includes a differentiation according to the consequences: incidents with release of radioactive materials resulting in restricted contamination, incidents with release of radioactive materials resulting in local contamination, and incidents with the hazard of e@nhanced exposure due to the radiation source.

  11. Mapping of the seasonal dynamic properties of building walls in actual periodic conditions and effects produced by solar radiation incident on the outer and inner surfaces of the wall

    International Nuclear Information System (INIS)

    Mazzeo, D.; Oliveti, G.; Arcuri, N.

    2016-01-01

    Highlights: • Dynamic thermal behaviour of building walls subjected to actual periodic loadings. • Dynamic parameters of wall in terms of energy and of heat flux are defined. • Different solar absorption coefficients and orientations of wall are considered. • On the internal surface is present or absent a shortwave radiant field. • Seasonal thermal characteristics for different plant operating regime are provided. - Abstract: In this work, the dynamic characteristics of the external walls of air-conditioned buildings subject to the joint action of periodic non-sinusoidal external and internal loadings are determined. The dynamic parameters used are the energy decrement factor, which is evaluated by means of the fluctuating heat flux in a semi-period exiting and entering the wall, the decrement factor of the maximum peak and minimum peak of the heat flux in a period and the relative time lags. The fluctuating heat flux in the wall in steady periodic regime conditions is determined with an analytical model obtained by resolving the equivalent electrical circuit. The preceding parameters are used for a study of the influence of solar radiation on the dynamic characteristics of the walls in summer and winter air-conditioning. Solar radiation is considered as operating on the external surface and on the internal surface due to the presence in the indoor environments of a shortwave radiant field. The absorbed solar heat flux by the external surface varies, modifying the solar absorption coefficient and wall orientation. Indoors, we considered a continuous operating regime of the plant and a regime with nocturnal attenuation. The results obtained, relating to 1152 different boundary conditions, were used for the construction of maps of dynamic characteristics, different on variation of the plant functioning regime and of the shortwave radiant load on the internal surface. The maps show the dependence of the decrement factors and of the time lags on variation of

  12. Optical tractor Bessel polarized beams

    International Nuclear Information System (INIS)

    Mitri, F.G.; Li, R.X.; Guo, L.X.; Ding, C.Y.

    2017-01-01

    Axial and transverse radiation force cross-sections of optical tractor Bessel polarized beams are theoretically investigated for a dielectric sphere with particular emphasis on the beam topological charge (or order), half-cone angle and polarization. The angular spectrum decomposition method (ASDM) is used to derive the non-paraxial electromagnetic (EM) field components of the Bessel beams. The multipole expansion method using vector spherical harmonics is utilized and appropriate beam-shape coefficients are derived in order to compute the radiation force cross-sections. The analysis has no limitation to a particular range of frequencies such that the Rayleigh, Mie or geometrical optics regimes can all be considered effectively using the present rigorous formalism. The focus of this investigation is to identify some of the tractor beam conditions so as to achieve retrograde motion of a dielectric sphere located arbitrarily in space. Numerical computations for the axial and transverse radiation force cross-sections are presented for linear, right-circular, radial, azimuthal and mixed polarizations of the individual plane waves forming the Bessel beams of zeroth- and first-order (with positive or negative helicity), respectively. As the sphere shifts off the beam's axis, the axial pulling (tractor) force is weakened. Moreover, the transverse radiation force cross-section field changes with the sphere's size factor ka (where k is the wavenumber and a is the sphere radius). Both stable and unstable equilibrium regions around the beam's axis are found, depending on the choice of ka and the half-cone angle α_0. These results are particularly important in the development of emergent technologies for the photophoretic assembly of optically-engineered (meta)materials with designed properties using optical tractor (vortex) beams, particle manipulation, levitation and positioning, and other applications. - Highlights: • Optical tractor Bessel polarized beams are

  13. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  14. Telecommunication using muon beams

    International Nuclear Information System (INIS)

    Arnold, R.C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location

  15. Comparative Incidence of Conformational, Neurodegenerative Disorders.

    Directory of Open Access Journals (Sweden)

    Jesús de Pedro-Cuesta

    Full Text Available The purpose of this study was to identify incidence and survival patterns in conformational neurodegenerative disorders (CNDDs.We identified 2563 reports on the incidence of eight conditions representing sporadic, acquired and genetic, protein-associated, i.e., conformational, NDD groups and age-related macular degeneration (AMD. We selected 245 papers for full-text examination and application of quality criteria. Additionally, data-collection was completed with detailed information from British, Swedish, and Spanish registries on Creutzfeldt-Jakob disease (CJD forms, amyotrophic lateral sclerosis (ALS, and sporadic rapidly progressing neurodegenerative dementia (sRPNDd. For each condition, age-specific incidence curves, age-adjusted figures, and reported or calculated median survival were plotted and examined.Based on 51 valid reported and seven new incidence data sets, nine out of eleven conditions shared specific features. Age-adjusted incidence per million person-years increased from ≤1.5 for sRPNDd, different CJD forms and Huntington's disease (HD, to 1589 and 2589 for AMD and Alzheimer's disease (AD respectively. Age-specific profiles varied from (a symmetrical, inverted V-shaped curves for low incidences to (b those increasing with age for late-life sporadic CNDDs and for sRPNDd, with (c a suggested, intermediate, non-symmetrical inverted V-shape for fronto-temporal dementia and Parkinson's disease. Frequently, peak age-specific incidences from 20-24 to ≥90 years increased with age at onset and survival. Distinct patterns were seen: for HD, with a low incidence, levelling off at middle age, and long median survival, 20 years; and for sRPNDd which displayed the lowest incidence, increasing with age, and a short median disease duration.These results call for a unified population view of NDDs, with an age-at-onset-related pattern for acquired and sporadic CNDDs. The pattern linking age at onset to incidence magnitude and survival might

  16. Comparative Incidence of Conformational, Neurodegenerative Disorders

    Science.gov (United States)

    de Pedro-Cuesta, Jesús; Rábano, Alberto; Martínez-Martín, Pablo; Ruiz-Tovar, María; Alcalde-Cabero, Enrique; Almazán-Isla, Javier; Avellanal, Fuencisla; Calero, Miguel

    2015-01-01

    Background The purpose of this study was to identify incidence and survival patterns in conformational neurodegenerative disorders (CNDDs). Methods We identified 2563 reports on the incidence of eight conditions representing sporadic, acquired and genetic, protein-associated, i.e., conformational, NDD groups and age-related macular degeneration (AMD). We selected 245 papers for full-text examination and application of quality criteria. Additionally, data-collection was completed with detailed information from British, Swedish, and Spanish registries on Creutzfeldt-Jakob disease (CJD) forms, amyotrophic lateral sclerosis (ALS), and sporadic rapidly progressing neurodegenerative dementia (sRPNDd). For each condition, age-specific incidence curves, age-adjusted figures, and reported or calculated median survival were plotted and examined. Findings Based on 51 valid reported and seven new incidence data sets, nine out of eleven conditions shared specific features. Age-adjusted incidence per million person-years increased from ≤1.5 for sRPNDd, different CJD forms and Huntington's disease (HD), to 1589 and 2589 for AMD and Alzheimer's disease (AD) respectively. Age-specific profiles varied from (a) symmetrical, inverted V-shaped curves for low incidences to (b) those increasing with age for late-life sporadic CNDDs and for sRPNDd, with (c) a suggested, intermediate, non-symmetrical inverted V-shape for fronto-temporal dementia and Parkinson's disease. Frequently, peak age-specific incidences from 20–24 to ≥90 years increased with age at onset and survival. Distinct patterns were seen: for HD, with a low incidence, levelling off at middle age, and long median survival, 20 years; and for sRPNDd which displayed the lowest incidence, increasing with age, and a short median disease duration. Interpretation These results call for a unified population view of NDDs, with an age-at-onset-related pattern for acquired and sporadic CNDDs. The pattern linking age at onset to

  17. Statics and rotational dynamics of composite beams

    CERN Document Server

    Ghorashi, Mehrdaad

    2016-01-01

    This book presents a comprehensive study of the nonlinear statics and dynamics of composite beams and consists of solutions with and without active elements embedded in the beams. The static solution provides the initial conditions for the dynamic analysis. The dynamic problems considered include the analyses of clamped (hingeless) and articulated (hinged) accelerating rotating beams. Two independent numerical solutions for the steady state and the transient responses are presented. The author illustrates that the transient solution of the nonlinear formulation of accelerating rotating beam converges to the steady state solution obtained by the shooting method. Other key areas considered include calculation of the effect of perturbing the steady state solution, coupled nonlinear flap-lag dynamics of a rotating articulated beam with hinge offset and aerodynamic damping, and static and dynamic responses of nonlinear composite beams with embedded anisotropic piezo-composite actuators. The book is intended as a t...

  18. Equilibrium state of colliding electron beams

    Directory of Open Access Journals (Sweden)

    R. L. Warnock

    2003-10-01

    Full Text Available We study a nonlinear integral equation that is a necessary condition on the equilibrium phase-space distribution function of stored, colliding electron beams. It is analogous to the Haïssinski equation, being derived from Vlasov-Fokker-Planck theory, but is quite different in form. The equation is analyzed for the case of the Chao-Ruth model of the beam-beam interaction in 1 degree of freedom, a so-called strong-strong model with nonlinear beam-beam force. We prove the existence of a unique solution, for sufficiently small beam current, by an application of the implicit function theorem. We have not yet proved that this solution is positive, as would be required to establish existence of an equilibrium. There is, however, numerical evidence of a positive solution. We expect that our analysis can be extended to more realistic models.

  19. Cold Leak Tests of LHC Beam Screens

    CERN Document Server

    Collomb-Patton, C; Jenninger, B; Kos, N

    2009-01-01

    In order to guide the high energy proton beams inside its two 27 km long vacuum rings, the Large Hadron Collider (LHC) at CERN, Geneva, makes use of superconducting technology to create the required magnetic fields. More than 4000 beam screens, cooled at 7 20 K, are inserted inside the 1.9 K beam vacuum tubes to intercept beam induced heat loads and to provide dynamic vacuum stability. As extremely high helium leak tightness is required, all beam screens have been leak tested under cold conditions in a dedicated test stand prior to their installation. After describing the beam screen design and its functions, this report focuses on the cold leak test sequence and discusses the results.

  20. Safe LHC beam commissioning

    International Nuclear Information System (INIS)

    Uythoven, J.; Schmidt, R.

    2007-01-01

    Due to the large amount of energy stored in magnets and beams, safety operation of the LHC is essential. The commissioning of the LHC machine protection system will be an integral part of the general LHC commissioning program. A brief overview of the LHC Machine Protection System will be given, identifying the main components: the Beam Interlock System, the Beam Dumping System, the Collimation System, the Beam Loss Monitoring System and the Quench Protection System. An outline is given of the commissioning strategy of these systems during the different commissioning phases of the LHC: without beam, injection and the different phases with stored beam depending on beam intensity and energy. (author)

  1. LANSCE beam current limiter

    International Nuclear Information System (INIS)

    Gallegos, F.R.

    1996-01-01

    The Radiation Security System (RSS) at the Los Alamos Neutron Science Center (LANSCE) provides personnel protection from prompt radiation due to accelerated beam. Active instrumentation, such as the Beam Current Limiter, is a component of the RSS. The current limiter is designed to limit the average current in a beam line below a specific level, thus minimizing the maximum current available for a beam spill accident. The beam current limiter is a self-contained, electrically isolated toroidal beam transformer which continuously monitors beam current. It is designed as fail-safe instrumentation. The design philosophy, hardware design, operation, and limitations of the device are described

  2. High power neutral beam injection in LHD

    International Nuclear Information System (INIS)

    Tsumori, K.; Takeiri, Y.; Nagaoka, K.

    2005-01-01

    The results of high power injection with a neutral beam injection (NBI) system for the large helical device (LHD) are reported. The system consists of three beam-lines, and two hydrogen negative ion (H - ion) sources are installed in each beam-line. In order to improve the injection power, the new beam accelerator with multi-slot grounded grid (MSGG) has been developed and applied to one of the beam-lines. Using the accelerator, the maximum powers of 5.7 MW were achieved in 2003 and 2004, and the energy of 189 keV reached at maximum. The power and energy exceeded the design values of the individual beam-line for LHD. The other beam-lines also increased their injection power up to about 4 MW, and the total injection power of 13.1 MW was achieved with three beam-lines in 2003. Although the accelerator had an advantage in high power beam injection, it involved a demerit in the beam focal condition. The disadvantage was resolved by modifying the aperture shapes of the steering grid. (author)

  3. Cerenkov light generated in optical fibres and other light pipes irradiated by electron beams

    International Nuclear Information System (INIS)

    Beddar, A.S.; Mackie, T.R.; Attix, F.H.

    1992-01-01

    The use of a small plastic scintillator coupled to an optical fibre bundle light pipe for the dosimetry of radiotherapy x-ray or electron beams in a phantom has been studied. Under such conditions, some light is generated by the direct action of the radiation on the optical fibres themselves, and this 'background' signal must be correctly accounted for. Electron beams were incident on fused silica optical fibres and other light pipes made of polymethylmethacrylate (PMMA), polystyrene and water. The observed light signal generated in all cases was found to depend strongly on the angle between the electron direction and the light pipe axis, and to correlate well with the angular characteristics uniquely associated with Cerenkov radiation. The use of a parallel fibre bundle light pipe, identical to the one that carries light from the scintillator, offers a suitable means of generating a similar background Cerenkov light signal that can be subtracted to obtain output from the scintillation dosimeter alone. (author)

  4. Beam splash effects on ATLAS silicon microstrip detectors evaluated using 1-w Nd YAG laser

    CERN Document Server

    Hara, K; Kohriki, T; Kuwano, T; Moorhead, G F; Terada, S; Unno, Y

    2005-01-01

    On an incident of accelerator beam loss, the tracking detector located close to the beam line is subjected to receive intensive radiation in a short period. We used a 1-W focused Nd: YAG laser and simulated the effects on the ATLAS microstrip detector. The laser corresponds to intensity of up to 1 multiplied by 109mips/pulse with a pulse width of about 10 ns. We observed breaks on Al strips on extreme conditions, depending on the laser intensity and bias voltage applied to the silicon sensor. The break can be interpreted as the oxide breakdown due to a large voltage locally created across the oxide by the intensive signal charges. The robustness of the Semiconductor Tracker (SCT) module including readout ASICs is also evaluated.

  5. Measurement of the broadening and depolarization of a Gaussian beam to transmit in fog water

    International Nuclear Information System (INIS)

    Serrano, G.; Reynoso, E; Davila, J. A.

    2012-01-01

    In this paper, we develop a controlled experimental environment in the laboratory, a waterproof camera where it will introduce artificial fog and become a beam of linearly polarized Gaussian laser light, creating sprawl, broadening and depolarization is studied with a system capable of measuring such phenomena. Most studies on dispersion have focused on the lobes of backscattering, however the correct conditions with the incident light beam a substantial fraction of light is scattered in the forward direction forming a widened light lobe. With this light lobe formed could be studied with extreme precision many factors such as the existence of single or multiple scattering and the amount by which this is carried out. This is of great importance in the estimation of lidar returns because these foundations can learn important information such as extinction and backscatter coefficients, particulate pollutants in the atmosphere and thus understand the operation model of nature. (Author)

  6. Application of electron beam irradiation, (1). Development and application of electron beam processors

    International Nuclear Information System (INIS)

    Katsumura, Yosuke

    1994-01-01

    This paper deals with characteristics, equipment (principle and kinds), present conditions, and future issues in the application of electron beam irradiation. Characteristics of electron beams are described in terms of the following: chemical and biological effects of radiation; energy and penetrating power of electron beams; and principle and kinds of electron beam accelerator. Industrial application of electron beam irradiation has advantages of high speed procedure and producibility, less energy, avoidance of poisonous gas, and extreme reduction of organic solvents to be used. The present application of electron beam irradiation cen be divided into the following: (1) hardening of resin or coated membrane; (2) improvement of macromolecular materials; (3) environmental protection; (4) sterilization; (5) food sterilization. The present equipment for electron beam irradiation is introduced according to low energy, medium energy, and high energy equipment. Finally, future issues focuses on (1) the improvement of traceability system and development of electron dosimetric techniques and (2) food sterilization. (N.K.)

  7. The beam dump tunnels

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    In these images workers are digging the tunnels that will be used to dump the counter-circulating beams. Travelling just a fraction under the speed of light, the beams at the LHC will each carry the energy of an aircraft carrier travelling at 12 knots. In order to dispose of these beams safely, a beam dump is used to extract the beam and diffuse it before it collides with a radiation shielded graphite target.

  8. Ion beam diagnosis

    International Nuclear Information System (INIS)

    Strehl, P.

    1994-04-01

    This report is an introduction to ion beam diagnosis. After a short description of the most important ion beam parameters measurements of the beam current by means of Faraday cups, calorimetry, and beam current transformers and measurements of the beam profile by means of viewing screens, profile grids and scanning devices, and residual gas ionization monitors are described. Finally measurements in the transverse and longitudinal phase space are considered. (HSI)

  9. Multipass autogenous electron beam welding

    International Nuclear Information System (INIS)

    Murphy, J.L.; Mustaleski, T.M. Jr.; Watson, L.C.

    1986-01-01

    A multipass, autogenous welding procedure was developed for 7.6 mm (0.3 in.) wall thickness Type 304L stainless steel cylinders. The joint geometry has a 1.5 mm (0.06 in.) root-face width and a rectangular stepped groove that is 0.762 mm (0.03 in.) wide at the top of the root face and extends 1.5 mm in height, terminating into a groove width of 1.27 mm which extends to the outside of the 1.27 mm high weld-boss. One weld pass is made on the root, three passes on the 0.762 mm wide groove and three passes to complete the weld. Multipass, autogenous, electron beam welds maintain the characteristic high depth-to-width ratios and low heat input of single-pass, electron beam welds. The increased part distortion (which is still much less than from arc processes) in multipass weldments is corrected by a preweld machined compensation. Mechanical properties of multipass welds compare well with single-pass welds. The yield strength of welds in aluminum alloy 5083 is approximately the same for single-pass or multipass electron beam and gas, metal-arc welds. The incidence and size of porosity is less in multipass electron beam welding of aluminum as compared to gas, metal-arc welds. The multipass, autogenous, electron beam welding method has proven to be a reliable way to make some difficult welds in multilayer parts or in an instance where inside part temperature or weld underbead must be controlled and weld discontinuities must be minimized

  10. Secondary electron emission of sapphire tungsten molybdenum and titanium for Maxwellian incident electrons

    International Nuclear Information System (INIS)

    Saussez-Hublet, M.-C.; Harbour, P.J.

    1980-06-01

    The second electron emission coefficient of various materials, namely titanium, molybdenum, tungsten and sapphire, has been calculated for a Maxwellian energy distribution from data for a normally incident monoenergetic beam of primary electrons. The most significant difference from the monoenergetic case occurs at low energies. In addition the influence of the incident angle of the electrons is discussed. (author)

  11. Contaminated Mexican steel incident

    International Nuclear Information System (INIS)

    1985-01-01

    This report documents the circumstances contributing to the inadvertent melting of cobalt 60 (Co-60) contaminated scrap metal in two Mexican steel foundries and the subsequent distribution of contaminated steel products into the United States. The report addresses mainly those actions taken by US Federal and state agencies to protect the US population from radiation risks associated with the incident. Mexico had much more serious radiation exposure and contamination problems to manage. The United States Government maintained a standing offer to provide technical and medical assistance to the Mexican Government. The report covers the tracing of the source to its origin, response actions to recover radioactive steel in the United States, and return of the contaminated materials to Mexico. The incident resulted in significant radiation exposures within Mexico, but no known significant exposure within the United States. Response to the incident required the combined efforts of the Nuclear Regulatory Commission (NRC), Department of Energy, Department of Transportation, Department of State, and US Customs Service (Department of Treasury) personnel at the Federal level and representatives of all 50 State Radiation Control Programs and, in some instances, local and county government personnel. The response also required a diplomatic interface with the Mexican Government and cooperation of numerous commercial establishments and members of the general public. The report describes the factual information associated with the event and may serve as information for subsequent recommendations and actions by the NRC. 8 figures

  12. Estimating cardiovascular disease incidence from prevalence: a spreadsheet based model

    Directory of Open Access Journals (Sweden)

    Xue Feng Hu

    2017-01-01

    Full Text Available Abstract Background Disease incidence and prevalence are both core indicators of population health. Incidence is generally not as readily accessible as prevalence. Cohort studies and electronic health record systems are two major way to estimate disease incidence. The former is time-consuming and expensive; the latter is not available in most developing countries. Alternatively, mathematical models could be used to estimate disease incidence from prevalence. Methods We proposed and validated a method to estimate the age-standardized incidence of cardiovascular disease (CVD, with prevalence data from successive surveys and mortality data from empirical studies. Hallett’s method designed for estimating HIV infections in Africa was modified to estimate the incidence of myocardial infarction (MI in the U.S. population and incidence of heart disease in the Canadian population. Results Model-derived estimates were in close agreement with observed incidence from cohort studies and population surveillance systems. This method correctly captured the trend in incidence given sufficient waves of cross-sectional surveys. The estimated MI declining rate in the U.S. population was in accordance with the literature. This method was superior to closed cohort, in terms of the estimating trend of population cardiovascular disease incidence. Conclusion It is possible to estimate CVD incidence accurately at the population level from cross-sectional prevalence data. This method has the potential to be used for age- and sex- specific incidence estimates, or to be expanded to other chronic conditions.

  13. Asymmetric-cut variable-incident-angle monochromator.

    Science.gov (United States)

    Smither, R K; Graber, T J; Fernandez, P B; Mills, D M

    2012-03-01

    A novel asymmetric-cut variable-incident-angle monochromator was constructed and tested in 1997 at the Advanced Photon Source of Argonne National Laboratory. The monochromator was originally designed as a high heat load monochromator capable of handling 5-10 kW beams from a wiggler source. This was accomplished by spreading the x-ray beam out on the surface an asymmetric-cut crystal and by using liquid metal cooling of the first crystal. The monochromator turned out to be a highly versatile monochromator that could perform many different types of experiments. The monochromator consisted of two 18° asymmetrically cut Si crystals that could be rotated about 3 independent axes. The first stage (Φ) rotates the crystal around an axis perpendicular to the diffraction plane. This rotation changes the angle of the incident beam with the surface of the crystal without changing the Bragg angle. The second rotation (Ψ) is perpendicular to the first and is used to control the shape of the beam footprint on the crystal. The third rotation (Θ) controls the Bragg angle. Besides the high heat load application, the use of asymmetrically cut crystals allows one to increase or decrease the acceptance angle for crystal diffraction of a monochromatic x-ray beam and allows one to increase or decrease the wavelength bandwidth of the diffraction of a continuum source like a bending-magnet beam or a normal x-ray-tube source. When the monochromator is used in the doubly expanding mode, it is possible to expand the vertical size of the double-diffracted beam by a factor of 10-15. When this was combined with a bending magnet source, it was possible to generate an 8 keV area beam, 16 mm wide by 26 mm high with a uniform intensity and parallel to 1.2 arc sec that could be applied in imaging experiments.

  14. Beam test performance of the SKIROC2 ASIC

    CERN Document Server

    Frisson, T; Anduze, M; Augustin, J.E; Bonis, J; Boudry, V; Bourgeois, C; Brient, J.C; Callier, S; Cerutti, M; Chen, S; Cornat, R; Cornebise, P; Cuisy, D; David, J; De la Taille, C; Dulucq, F; Frotin, M; Gastaldi, F; Ghislain, P; Giraud, J; Gonnin, A; Grondin, D; Guliyev, E; Hostachy, J.Y; Jeans, D; Kamiya, Y; Kawagoe, K; Kozakai, C; Lacour, D; Lavergne, L; Lee, S.H; Magniette, F; Ono, H; Poeschl, R; Rouëné, J; Seguin-Moreau, N; Song, H.S; Sudo, Y; Thiebault, A; Tran, H; Ueno, H; Van der Kolk, N; Yoshioka, T

    2015-01-01

    Beam tests of the first layers of CALICE silicon tungsten ECAL technological prototype were performed in April and July 2012 using 1–6 GeV electron beam at DESY. This paper presents an analysis of the SKIROC2 readout ASIC performance under test beam conditions.

  15. A pioneer experience in Malaysia on In-house Radio-labelling of "1"3"1I-rituximab in the treatment of Non-Hodgkin's Lymphoma and a case report of high dose "1"3"1I-rituximab-BEAM conditioning autologous transplant

    International Nuclear Information System (INIS)

    Kuan, Jew Win; Law, Chiong Soon; Wong, Xiang Qi; Ko, Ching Tiong; Awang, Zool Hilmi; Chew, Lee Ping; Chang, Kian Meng

    2016-01-01

    Radioimmunotherapy is an established treatment modality in Non-Hodgkin's lymphoma. The only two commercially available radioimmunotherapies – "9"0Y-ibritumomab tiuxetan is expensive and "1"3"1I-tositumomab has been discontinued from commercial production. In resource limited environment, self-labelling "1"3"1I-rituximab might be the only viable practical option. We reported our pioneer experience in Malaysia on self-labelling "1"3"1I-rituximab, substituting autologous haematopoietic stem cell transplantation (HSCT) and a patient, the first reported case, received high dose "1"3"1I-rituximab (6000 MBq/163 mCi) combined with BEAM conditioning for autologous HSCT. - Highlights: • Usual dose: Day 0 (dosimetry) – 5 mCi, Day 7 (therapeutic) 0.75 Gy to whole body. • High dose: 6000 MBq (163 mCi) on Day − 18, BEAM conditioning starts on Day − 8. • Self-labelled "1"3"1I-rituximab is a viable treatment in resource limited environment. • "1"3"1I-rituximab may substitute autologous transplant. • High dose "1"3"1I-rituximab-BEAM is a feasible conditioning regime.

  16. Beam diagnostics for low energy beams

    Directory of Open Access Journals (Sweden)

    J. Harasimowicz

    2012-12-01

    Full Text Available Low-energetic ion and antimatter beams are very attractive for a number of fundamental studies. The diagnostics of such beams, however, is a challenge due to low currents down to only a few thousands of particles per second and significant fraction of energy loss in matter at keV beam energies. A modular set of particle detectors has been developed to suit the particular beam diagnostic needs of the ultralow-energy storage ring (USR at the future facility for low-energy antiproton and ion research, accommodating very low beam intensities at energies down to 20 keV. The detectors include beam-profile monitors based on scintillating screens and secondary electron emission, sensitive Faraday cups for absolute intensity measurements, and capacitive pickups for beam position monitoring. In this paper, the design of all detectors is presented in detail and results from beam measurements are shown. The resolution limits of all detectors are described and options for further improvement summarized. Whilst initially developed for the USR, the instrumentation described in this paper is also well suited for use in other low-intensity, low-energy accelerators, storage rings, and beam lines.

  17. Medication incidents reported to an online incident reporting system.

    LENUS (Irish Health Repository)

    Alrwisan, Adel

    2011-01-15

    AIMS: Approximately 20% of deaths from adverse events are related to medication incidents, costing the NHS an additional £500 million annually. Less than 5% of adverse events are reported. This study aims to assess the reporting rate of medication incidents in NHS facilities in the north east of Scotland, and to describe the types and outcomes of reported incidents among different services. Furthermore, we wished to quantify the proportion of reported incidents according to the reporters\\' profession. METHODS: A retrospective description was made of medication incidents reported to an online reporting system (DATIX) over a 46-month-period (July 2005 to April 2009). Reports originated from acute and community hospitals, mental health, and primary care facilities. RESULTS: Over the study period there were 2,666 incidents reported with a mean monthly reporting rate of 78.2\\/month (SD±16.9). 6.1% of all incidents resulted in harm, with insulin being the most commonly implicated medication. Nearly three-quarters (74.2%, n=1,978) of total incidents originated from acute hospitals. Administration incidents were implicated in the majority of the reported medication incidents (59%), followed by prescribing (10.8%) and dispensing (9.9%), while the nondescript "other medication incidents" accounted for 20.3% of total incidents. The majority of reports were made by nursing and midwifery staff (80%), with medical and dental professionals reporting the lowest number of incidents (n=56, 2%). CONCLUSIONS: The majority of medication incidents in this study were reported by nursing and midwifery staff, and were due to administration incidents. There is a clear need to elucidate the reasons for the limited contribution of the medical and dental professionals to reporting medication incidents.

  18. Influence of laser beam profiles on received power fluctuation

    Science.gov (United States)

    Dordova, Lucie; Diblik, Jan

    2011-09-01

    Gaussian beam is very often used for the transmission of information in optical wireless links. The usage of this optical beam has its advantages and, of course, disadvantages. This work focuses on possibilities of using laser beams with different distribution of optical intensity - Top Hat beam. Creation of the optical beam with selected optical intensity profile will be briefly described. Optical beams will propagate through the "clear" and stationary atmosphere in the experimental part of this work. These results will be compared with the data obtained after a laser beam is passed through the turbulent and attenuated atmosphere. We will use an ultrasound fog generator for laser beam attenuation testing. To create the turbulence, infra radiators will be applied. Particular results obtained from different atmospheric conditions will be compared and using different types of optical beams will be assessed.

  19. LHC beam dumping system Extraction channel layout and acceptance

    CERN Document Server

    Goddard, B; Uythoven, J; Veness, R; Weterings, W

    2003-01-01

    The LHC beam dumping system must safely abort the LHC beams under all conditions, including those resulting from abnormal behaviour of machine elements or subsystems of the beam dumping system itself. The extraction channels must provide sufficient aperture both for the circulating and extracted beams, over the whole energy range and under various beam parameters. These requirements impose tight constraints on the tolerances of various extraction channel components, and also on the allowed range of beam positions in the region of these components. Operation of the beam dumping system under various fault states has been considered, and the resulting apertures calculated. After describing briefly the beam dumping system and the extraction channel geometry, the various assumptions made in the analysis are presented, before deriving tolerance limits for the relevant equipment and beam parameters.

  20. Stability Analysis of Nonuniform Rectangular Beams Using Homotopy Perturbation Method

    Directory of Open Access Journals (Sweden)

    Seval Pinarbasi

    2012-01-01

    Full Text Available The design of slender beams, that is, beams with large laterally unsupported lengths, is commonly controlled by stability limit states. Beam buckling, also called “lateral torsional buckling,” is different from column buckling in that a beam not only displaces laterally but also twists about its axis during buckling. The coupling between twist and lateral displacement makes stability analysis of beams more complex than that of columns. For this reason, most of the analytical studies in the literature on beam stability are concentrated on simple cases: uniform beams with ideal boundary conditions and simple loadings. This paper shows that complex beam stability problems, such as lateral torsional buckling of rectangular beams with variable cross-sections, can successfully be solved using homotopy perturbation method (HPM.

  1. Optimizing beam transport in rapidly compressing beams on the neutralized drift compression experiment – II

    Directory of Open Access Journals (Sweden)

    Anton D. Stepanov

    2018-03-01

    Full Text Available The Neutralized Drift Compression Experiment-II (NDCX-II is an induction linac that generates intense pulses of 1.2 MeV helium ions for heating matter to extreme conditions. Here, we present recent results on optimizing beam transport. The NDCX-II beamline includes a 1-m-long drift section downstream of the last transport solenoid, which is filled with charge-neutralizing plasma that enables rapid longitudinal compression of an intense ion beam against space-charge forces. The transport section on NDCX-II consists of 28 solenoids. Finding optimal field settings for a group of solenoids requires knowledge of the envelope parameters of the beam. Imaging the beam on the scintillator gives the radius of the beam, but the envelope angle is not measured directly. We demonstrate how the parameters of the beam envelope (radius, envelop angle, and emittance can be reconstructed from a series of images taken by varying the B-field strengths of a solenoid upstream of the scintillator. We use this technique to evaluate emittance at several points in the NDCX-II beamline and for optimizing the trajectory of the beam at the entry of the plasma-filled drift section. Keywords: Charged-particle beams, Induction accelerators, Beam dynamics, Beam emittance, Ion beam diagnostics, PACS Codes: 41.75.-i, 41.85.Ja, 52.59.Sa, 52.59.Wd, 29.27.Eg

  2. Ion-beam nanopatterning: experimental results with chemically-assisted beam

    Science.gov (United States)

    Pochon, Sebastien C. R.

    2018-03-01

    The need for forming gratings (for example used in VR headsets) in materials such as SiO2 has seen a recent surge in the use of Ion beam etching techniques. However, when using an argon-only beam, the selectivity is limited as it is a physical process. Typically, gases such as CHF3, SF6, O2 and Cl2 can be added to argon in order to increase selectivity; depending on where the gas is injected, the process is known as Reactive Ion Beam Etching (RIBE) or Chemically Assisted Ion Beam Etching (CAIBE). The substrate holder can rotate in order to provide an axisymmetric etch rate profile. It can also be tilted over a range of angles to the beam direction. This enables control over the sidewall profile as well as radial uniformity optimisation. Ion beam directionality in conjunction with variable incident beam angle via platen angle setting enables profile control and feature shaping during nanopatterning. These hardware features unique to the Ion Beam etching methods can be used to create angled etch features. The CAIBE technique is also well suited to laser diode facet etch (for optoelectronic devices); these typically use III-V materials like InP. Here, we report on materials such as SiO2 etched without rotation and at a fixed platen angle allowing the formation of gratings and InP etched at a fixed angle with rotation allowing the formation of nanopillars and laser facets.

  3. Studies of the beam-beam interaction for the LHC

    International Nuclear Information System (INIS)

    Krishnagopal, S.; Furman, M.A.; Turner, W.C.

    1999-01-01

    The authors have used the beam-beam simulation code CBI to study the beam-beam interaction for the LHC. We find that for nominal LHC parameters, and assuming only one bunch per beam, there are no collective (coherent) beam-beam instabilities. We have investigated the effect of sweeping one of the beams around the other (a procedure that could be used as a diagnostic for head-on beam-beam collisions). We find that this does not cause any problems at the nominal current, though at higher currents there can be beam blow-up and collective beam motion. consequence of quadrupole collective effects

  4. The incidence of urea cycle disorders.

    Science.gov (United States)

    Summar, Marshall L; Koelker, Stefan; Freedenberg, Debra; Le Mons, Cynthia; Haberle, Johannes; Lee, Hye-Seung; Kirmse, Brian

    2013-01-01

    A key question for urea cycle disorders is their incidence. In the United States two UCDs, argininosuccinic synthetase and lyase deficiency, are currently detected by newborn screening. We used newborn screening data on over 6million births and data from the large US and European longitudinal registries to determine how common these conditions are. The incidence for the United States is predicted to be 1 urea cycle disorder patient for every 35,000 births presenting about 113 new patients per year across all age groups. © 2013.

  5. ORNL 150 keV neutral beam test facility

    International Nuclear Information System (INIS)

    Gardner, W.L.; Kim, J.; Menon, M.M.; Schilling, G.

    1977-01-01

    The 150 keV neutral beam test facility provides for the testing and development of neutral beam injectors and beam systems of the class that will be needed for the Tokamak Fusion Test Reactor (TFTR) and The Next Step (TNS). The test facility can simulate a complete beam line injection system and can provide a wide range of experimental operating conditions. Herein is offered a general description of the facility's capabilities and a discussion of present system performance

  6. Electron beam cladding of titanium on stainless steel plate

    International Nuclear Information System (INIS)

    Tomie, Michio; Abe, Nobuyuki; Yamada, Masanori; Noguchi, Shuichi.

    1990-01-01

    Fundamental characteristics of electron beam cladding was investigated. Titanium foil of 0.2mm thickness was cladded on stainless steel plate of 3mm thickness by scanning electron beam. Surface roughness and cladded layer were analyzed by surface roughness tester, microscope, scanning electron microscope and electron probe micro analyzer. Electron beam conditions were discussed for these fundamental characteristics. It is found that the energy density of the electron beam is one of the most important factor for cladding. (author)

  7. Prevalence Incidence Mixture Models

    Science.gov (United States)

    The R package and webtool fits Prevalence Incidence Mixture models to left-censored and irregularly interval-censored time to event data that is commonly found in screening cohorts assembled from electronic health records. Absolute and relative risk can be estimated for simple random sampling, and stratified sampling (the two approaches of superpopulation and a finite population are supported for target populations). Non-parametric (absolute risks only), semi-parametric, weakly-parametric (using B-splines), and some fully parametric (such as the logistic-Weibull) models are supported.

  8. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A; Laird, J S; Bardos, R A; Legge, G J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T; Sekiguchi, H [Electrotechnical Laboratory, Tsukuba (Japan).

    1994-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  9. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A.; Laird, J.S.; Bardos, R.A.; Legge, G.J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T.; Sekiguchi, H. [Electrotechnical Laboratory, Tsukuba (Japan).

    1993-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  10. Scattering of a high-order Bessel beam by a spheroidal particle

    Science.gov (United States)

    Han, Lu

    2018-05-01

    Within the framework of generalized Lorenz-Mie theory (GLMT), scattering from a homogeneous spheroidal particle illuminated by a high-order Bessel beam is formulated analytically. The high-order Bessel beam is expanded in terms of spheroidal vector wave functions, where the spheroidal beam shape coefficients (BSCs) are computed conveniently using an intrinsic method. Numerical results concerning scattered field in the far zone are displayed for various parameters of the incident Bessel beam and of the scatter. These results are expected to provide useful insights into the scattering of a Bessel beam by nonspherical particles and particle manipulation applications using Bessel beams.

  11. Incorporating prior knowledge into beam orientation optimization in IMRT

    International Nuclear Information System (INIS)

    Pugachev, Andrei M.S.; Lei Xing

    2002-01-01

    Purpose: Selection of beam configuration in currently available intensity-modulated radiotherapy (IMRT) treatment planning systems is still based on trial-and-error search. Computer beam orientation optimization has the potential to improve the situation, but its practical implementation is hindered by the excessive computing time associated with the calculation. The purpose of this work is to provide an effective means to speed up the beam orientation optimization by incorporating a priori geometric and dosimetric knowledge of the system and to demonstrate the utility of the new algorithm for beam placement in IMRT. Methods and Materials: Beam orientation optimization was performed in two steps. First, the quality of each possible beam orientation was evaluated using beam's-eye-view dosimetrics (BEVD) developed in our previous study. A simulated annealing algorithm was then employed to search for the optimal set of beam orientations, taking into account the BEVD scores of different incident beam directions. During the calculation, sampling of gantry angles was weighted according to the BEVD score computed before the optimization. A beam direction with a higher BEVD score had a higher probability of being included in the trial configuration, and vice versa. The inclusion of the BEVD weighting in the stochastic beam angle sampling process made it possible to avoid spending valuable computing time unnecessarily at 'bad' beam angles. An iterative inverse treatment planning algorithm was used for beam intensity profile optimization during the optimization process. The BEVD-guided beam orientation optimization was applied to an IMRT treatment of paraspinal tumor. The advantage of the new optimization algorithm was demonstrated by comparing the calculation with the conventional scheme without the BEVD weighting in the beam sampling. Results: The BEVD tool provided useful guidance for the selection of the potentially good directions for the beams to incident and was used

  12. Improving freight crash incident management.

    Science.gov (United States)

    2015-06-01

    The objective of this study was to determine the most effective way to mitigate the effect of freight : crash incidents on Louisiana freeways. Candidate incident management strategies were reviewed from : practice in other states and from those publi...

  13. A beam monitor using silicon pixel sensors for hadron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhen, E-mail: zwang@mails.ccnu.edu.cn; Zou, Shuguang; Fan, Yan; Liu, Jun; Sun, Xiangming, E-mail: sphy2007@126.com; Wang, Dong; Kang, Huili; Sun, Daming; Yang, Ping; Pei, Hua; Huang, Guangming; Xu, Nu; Gao, Chaosong; Xiao, Le

    2017-03-21

    We report the design and test results of a beam monitor developed for online monitoring in hadron therapy. The beam monitor uses eight silicon pixel sensors, Topmetal-II{sup -}, as the anode array. Topmetal-II{sup -} is a charge sensor designed in a CMOS 0.35 µm technology. Each Topmetal-II{sup -} sensor has 72×72 pixels and the pixel size is 83×83 µm{sup 2}. In our design, the beam passes through the beam monitor without hitting the electrodes, making the beam monitor especially suitable for monitoring heavy ion beams. This design also reduces radiation damage to the beam monitor itself. The beam monitor is tested with a carbon ion beam at the Heavy Ion Research Facility in Lanzhou (HIRFL). Results indicate that the beam monitor can measure position, incidence angle and intensity of the beam with a position resolution better than 20 µm, angular resolution about 0.5° and intensity statistical accuracy better than 2%.

  14. Increasing incidence of pyogenic spondylodiscitis

    DEFF Research Database (Denmark)

    Kehrer, Michala; Pedersen, Court; Jensen, Thøger G

    2014-01-01

    Smaller studies indicate that the incidence of pyogenic spondylodiscitis is increasing, possible related to a growing elderly population. Data supporting this is sparse, and we therefore studied patient characteristics and changes in spondylodiscitis incidence 1995-2008.......Smaller studies indicate that the incidence of pyogenic spondylodiscitis is increasing, possible related to a growing elderly population. Data supporting this is sparse, and we therefore studied patient characteristics and changes in spondylodiscitis incidence 1995-2008....

  15. The generation of absorbed dose profiles of proton beam in water using Geant4 code

    International Nuclear Information System (INIS)

    Christovao, Marilia T.; Campos, Tarcisio Passos R. de

    2007-01-01

    The present article approaches simulations on the proton beam radiation therapy, using an application based on the code GEANT4, with Open GL as a visualization drive and JAS3 (Java Analysis Studio) analysis data tools systems, implementing the AIDA interfaces. The proton radiotherapy is adapted to treat cancer or other benign tumors that are close to sensitive structures, since it allows precise irradiation of the target with high doses, while the health tissues adjacent to vital organs and tissues are preserved, due to physical property of dose profile. GEANT4 is a toolkit for simulating the transport of particles through matter, in complex geometries. Taking advantage of the object-oriented project features, the user can adapt or extend the tool in all domain, due to the flexibility of the code, providing a subroutine's group for materials definition, geometries and particles properties in agreement with the user's needs to generate the Monte Carlo simulation. In this paper, the parameters of beam line used in the simulation possess adjustment elements, such as: the range shifter, composition and dimension; the beam line, energy, intensity, length, according with physic processes applied. The simulation result is the depth dose profiles on water, dependent on the various incident beam energy. Starting from those profiles, one can define appropriate conditions for proton radiotherapy in ocular region. (author)

  16. Beam Dynamics and Beam Losses - Circular Machines

    CERN Document Server

    Kain, V

    2016-01-01

    A basic introduction to transverse and longitudinal beam dynamics as well as the most relevant beam loss mechanisms in circular machines will be presented in this lecture. This lecture is intended for physicists and engineers with little or no knowledge of this subject.

  17. Electron beam instabilities in gyrotron beam tunnels

    International Nuclear Information System (INIS)

    Pedrozzi, M.; Alberti, S.; Hogge, J.P.; Tran, M.Q.; Tran, T.M.

    1997-10-01

    Electron beam instabilities occurring in a gyrotron electron beam can induce an energy spread which might significantly deteriorate the gyrotron efficiency. Three types of instabilities are considered to explain the important discrepancy found between the theoretical and experimental efficiency in the case of quasi-optical gyrotrons (QOG): the electron cyclotron maser instability, the Bernstein instability and the Langmuir instability. The low magnetic field gradient in drift tubes of QOG makes that the electron cyclotron maser instability can develop in the drift tube at very low electron beam currents. Experimental measurements show that with a proper choice of absorbing structures in the beam tunnel, this instability can be suppressed. At high beam currents, the electrostatic Bernstein instability can induce a significant energy spread at the entrance of the interaction region. The induced energy spread scales approximately linearly with the electron beam density and for QOG one observes that the beam density is significantly higher than the beam density of an equivalent cylindrical cavity gyrotron. (author) figs., tabs., refs

  18. Incident Management: Process into Practice

    Science.gov (United States)

    Isaac, Gayle; Moore, Brian

    2011-01-01

    Tornados, shootings, fires--these are emergencies that require fast action by school district personnel, but they are not the only incidents that require risk management. The authors have introduced the National Incident Management System (NIMS) and the Incident Command System (ICS) and assured that these systems can help educators plan for and…

  19. Successful Beam-Beam Tuneshift Compensation

    Energy Technology Data Exchange (ETDEWEB)

    Bishofberger, Kip Aaron [Univ. of California, Los Angeles, CA (United States)

    2005-01-01

    The performance of synchrotron colliders has been limited by the beam-beam limit, a maximum tuneshift that colliding bunches could sustain. Due to bunch-to-bunch tune variation and intra-bunch tune spread, larger tuneshifts produce severe emittance growth. Breaking through this constraint has been viewed as impossible for several decades. This dissertation introduces the physics of ultra-relativistic synchrotrons and low-energy electron beams, with emphasis placed on the limits of the Tevatron and the needs of a tuneshift-compensation device. A detailed analysis of the Tevatron Electron Lens (TEL) is given, comparing theoretical models to experimental data whenever possible. Finally, results of Tevatron operations with inclusion of the TEL are presented and analyzed. It is shown that the TEL provides a way to shatter the previously inescapable beam-beam limit.

  20. BEAMS3D Neutral Beam Injection Model

    Energy Technology Data Exchange (ETDEWEB)

    Lazerson, Samuel

    2014-04-14

    With the advent of applied 3D fi elds in Tokamaks and modern high performance stellarators, a need has arisen to address non-axisymmetric effects on neutral beam heating and fueling. We report on the development of a fully 3D neutral beam injection (NBI) model, BEAMS3D, which addresses this need by coupling 3D equilibria to a guiding center code capable of modeling neutral and charged particle trajectories across the separatrix and into the plasma core. Ionization, neutralization, charge-exchange, viscous velocity reduction, and pitch angle scattering are modeled with the ADAS atomic physics database [1]. Benchmark calculations are presented to validate the collisionless particle orbits, neutral beam injection model, frictional drag, and pitch angle scattering effects. A calculation of neutral beam heating in the NCSX device is performed, highlighting the capability of the code to handle 3D magnetic fields.