WorldWideScience

Sample records for beam energy measurement

  1. MEV Energy Electrostatic Accelerator Ion Beam Emittance Measurement

    OpenAIRE

    I.G. Ignat’ev; M.I. Zakharets; S.V. Kolinko; D.P. Shulha

    2014-01-01

    The testing equipment was designed, manufactured and tried out permitting measurements of total current, current profile and emittance of an ion beam extracted from the ion beam. MeV energy electrostatic accelerator ion H + beam emittance measurement results are presented.

  2. Compact Measurement Station for Low Energy Proton Beams

    CERN Document Server

    Yildiz, H.

    2017-02-24

    A compact, remote controlled, cost efficient diagnostic station has been developed to measure the charge, the profile and the emittance for low energy proton beams. It has been installed and tested in the proton beam line of the Project Prometheus at SANAEM of the Turkish Atomic Energy Authority.

  3. Measuring the electron beam energy in a magnetic bunch compressor

    International Nuclear Information System (INIS)

    Hacker, Kirsten

    2010-09-01

    Within this thesis, work was carried out in and around the first bunch compressor chicane of the FLASH (Free-electron LASer in Hamburg) linear accelerator in which two distinct systems were developed for the measurement of an electron beams' position with sub-5 μm precision over a 10 cm range. One of these two systems utilized RF techniques to measure the difference between the arrival-times of two broadband electrical pulses generated by the passage of the electron beam adjacent to a pickup antenna. The other system measured the arrival-times of the pulses from the pickup with an optical technique dependent on the delivery of laser pulses which are synchronized to the RF reference of the machine. The relative advantages and disadvantages of these two techniques are explored and compared to other available approaches to measure the same beam property, including a time-of-flight measurement with two beam arrival-time monitors and a synchrotron light monitor with two photomultiplier tubes. The electron beam position measurement is required as part of a measurement of the electron beam energy and could be used in an intra-bunch-train beam-based feedback system that would stabilize the amplitude of the accelerating field. By stabilizing the accelerating field amplitude, the arrival-time of the electron beam can be made more stable. By stabilizing the electron beam arrival-time relative to a stable reference, diagnostic, seeding, and beam-manipulation lasers can be synchronized to the beam. (orig.)

  4. A beam energy measurement system at NIRS-930 cyclotron

    International Nuclear Information System (INIS)

    Hojo, S.; Honma, T.; Sakamoto, Y.; Miyahara, N.; Okada, T.; Komatsu, K.; Tsuji, N.; Yamada, S.

    2005-01-01

    A beam energy measurement system employing a set of capacitive probes has been developed at NIRS-930 cyclotron. Principle of the measurement is applying a modified-TOF method, so that the two proves are installed at one of the straight section in the beam transport line. Usually they are separated about 5.8 m, which is equivalent to the almost final path length of the beam extracted in the cyclotron. In the measurement, two beam signals are superimposed by adjusting a position of the downstream-probe along the beam direction with watching an oscilloscope screen roughly. In order to determine the beam energy accurately the signals are processed by MCA with suitable electric module. (author)

  5. Linac4 Low Energy Beam Measurements with Negative Hydrogen

    CERN Document Server

    Scrivens, R; Crettiez, O; Dimov, V; Gerard, D; Granemann Souza, E; Guida, R; Hansen, J; Lallement, J B; Lettry, J; Lombardi, A; Midttun, O; Pasquino, C; Raich, U; Riffaud, B; Roncarolo, F; Valerio-Lizarraga, C A; Wallner, J; Yarmohammadi Satri, M; Zickler, T

    2014-01-01

    Linac4, a 160 MeV normal-conducting H- linear accelerator, is the first step in the upgrade of the beam intensity available from the LHC proton injectors at CERN. The Linac4 Low Energy Beam Transport (LEBT) line from the pulsed 2 MHz RF driven ion source, to the 352 MHz RFQ has been built and installed at a test stand, and has been used to transport and match to the RFQ a pulsed 14 mA H- beam at 45 keV. A temporary slit-and-grid emittance measurement system has been put in place to characterize the beam delivered to the RFQ. In this paper a description of the LEBT and its beam diagnostics is given, and the results of beam emittance measurements and beam transmission measurements through the RFQ are compared with the expectation from simulations.

  6. Faraday Cup - it is used to measure beam intensities at low energy beams.

    CERN Multimedia

    Maximilien Brice

    2005-01-01

    A Faraday Cup is used to measure beam intensities at low energy beams. An electrically isolated metallic electrode intercepts the beam and captures all its charges. These charges are integrated using an current sensitive amplifier. When the beam impinges onto the electrode surface low energy electrons are liberated. In order to prevent these electrons from escaping the cup and thus falsifying the measurement, a repeller electrode with negative potential pushes the electrons back onto the electrode.

  7. Precision measurements of the SLC [Stanford Linear Collider] beam energy

    International Nuclear Information System (INIS)

    Kent, J.; King, M.; Von Zanthier, C.

    1989-03-01

    A method of precisely determining the beam energy in high energy linear colliders has been developed using dipole spectrometers and synchrotron radiation detectors. Beam lines implementing this method have been installed on the Stanford Linear Collider. An absolute energy measurement with an accuracy of better than δE/E = 5 /times/ 10/sup /minus/4/ can be achieved on a pulse-to-pulse basis. The operation of this system will be described. 4 refs., 3 figs., 1 tab

  8. Measurement of beam energy spread in a space-charge dominated electron beam

    Directory of Open Access Journals (Sweden)

    Y. Cui

    2004-07-01

    Full Text Available Characterization of beam energy spread in a space-charge dominated beam is very important to understanding the physics of intense beams. It is believed that coupling between the transverse and longitudinal directions via Coulomb collisions will cause an increase of the beam longitudinal energy spread. At the University of Maryland, experiments have been carried out to study the energy evolution in such intense beams with a high-resolution retarding field energy analyzer. The temporal beam energy profile along the beam pulse has been characterized at the distance of 25 cm from the anode of a gridded thermionic electron gun. The mean energy of the pulsed beams including the head and tail is reported here. The measured rms energy spread is in good agreement with the predictions of the intrabeam scattering theory. As an application of the beam energy measurement, the input impedance between the cathode and the grid due to beam loading can be calculated and the impedance number is found to be a constant in the operation region of the gun.

  9. Measuring the electron beam energy in a magnetic bunch compressor

    Energy Technology Data Exchange (ETDEWEB)

    Hacker, Kirsten

    2010-09-15

    Within this thesis, work was carried out in and around the first bunch compressor chicane of the FLASH (Free-electron LASer in Hamburg) linear accelerator in which two distinct systems were developed for the measurement of an electron beams' position with sub-5 {mu}m precision over a 10 cm range. One of these two systems utilized RF techniques to measure the difference between the arrival-times of two broadband electrical pulses generated by the passage of the electron beam adjacent to a pickup antenna. The other system measured the arrival-times of the pulses from the pickup with an optical technique dependent on the delivery of laser pulses which are synchronized to the RF reference of the machine. The relative advantages and disadvantages of these two techniques are explored and compared to other available approaches to measure the same beam property, including a time-of-flight measurement with two beam arrival-time monitors and a synchrotron light monitor with two photomultiplier tubes. The electron beam position measurement is required as part of a measurement of the electron beam energy and could be used in an intra-bunch-train beam-based feedback system that would stabilize the amplitude of the accelerating field. By stabilizing the accelerating field amplitude, the arrival-time of the electron beam can be made more stable. By stabilizing the electron beam arrival-time relative to a stable reference, diagnostic, seeding, and beam-manipulation lasers can be synchronized to the beam. (orig.)

  10. ILC beam energy measurement by means of laser Compton backscattering

    Energy Technology Data Exchange (ETDEWEB)

    Muchnoi, N. [Budker Inst. for Nuclear Physics, Novosibirsk (Russian Federation); Schreiber, H.J.; Viti, M. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

    2008-10-15

    A novel, non-invasive method of measuring the beam energy at the International Linear Collider is proposed. Laser light collides head-on with beam particles and either the energy of the Compton scattered electrons near the kinematic end-point is measured or the positions of the Compton backscattered {gamma}-rays, the edge electrons and the unscattered beam particles are recorded. A compact layout for the Compton spectrometer is suggested. It consists of a bending magnet and position sensitive detectors operating in a large radiation environment. Several options for high spatial resolution detectors are discussed. Simulation studies support the use of an infrared or green laser and quartz fiber detectors to monitor the backscattered photons and edge electrons. Employing a cavity monitor, the beam particle position downstream of the magnet can be recorded with submicrometer precision. Such a scheme provides a feasible and promising method to access the incident beam energy with precisions of 10{sup -4} or better on a bunch-to-bunch basis while the electron and positron beams are in collision. (orig.)

  11. Measurement of beam energy spectrum and impurity content in high-power neutral beam injectors

    International Nuclear Information System (INIS)

    Langley, R.A.; Ryan, P.M.; Tsai, C.C.; Menon, M.M.; Botnick, E.M.; Magee, C.W.

    1985-01-01

    The energy spectrum and impurity content of a high-power neutral beam are measured by implanting the beam into high-purity silicon crystals. The depth distribution of the beam particles is then measured by secondary ion mass spectrometry (SIMS); the penetration depth is a function of the incident particle energy. This is one of the few measurement techniques that can determine neutral beam energy components directly. From the results, percentages of atomic and molecular ions in the source plasma can be inferred. Use of deuterium as the source gas provides insight into the role of residual hydrogen in the ion source and accelerating grids and in the SIMS analysis. The principal impurities are carbon and oxygen. Preliminary data indicate that carbon can originate from both methane and carbon monoxide, while oxygen can come from molecular oxygen, carbon monoxide, and water. Results are given and future plans are discussed

  12. Noninterceptive beam energy measurements in line D of the Los Alamos Meson Physics Facility

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.; Carter, H.; Plum, M.; Power, J.F.; Rose, C.R.; Shurter, R.B.

    1995-01-01

    Several members of the Accelerator and Operations Technology (AOT) division beam-diagnostics team performed time-of-flight (TOF) beam-energy measurements in line D of the Los Alamos Meson Physics Facility (LAMPF) using developmental beam time. These measurements provided information for a final design of an on-line beam energy measurement. The following paper discusses these measurements and how they apply to the final beam energy measurement design

  13. Measurement of ultra-low ion energy of decelerated ion beam using a deflecting electric field

    Energy Technology Data Exchange (ETDEWEB)

    Thopan, P.; Suwannakachorn, D.; Tippawan, U. [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, L.D., E-mail: yuld@thep-center.org [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2015-12-15

    In investigation on ultra-low-energy ion bombardment effect on DNA, an ion beam deceleration lens was developed for high-quality ultra-low-energy ion beam. Measurement of the ion energy after deceleration was necessary to confirm the ion beam really decelerated as theoretically predicted. In contrast to conventional methods, this work used a simple deflecting electrostatic field after the deceleration lens to bend the ion beam. The beam bending distance depended on the ion energy and was described and simulated. A system for the measurement of the ion beam energy was constructed. It consisted of a pair of parallel electrode plates to generate the deflecting electrical field, a copper rod measurement piece to detect ion beam current, a vernier caliper to mark the beam position, a stepping motor to translate the measurement rod, and a webcam-camera to read the beam bending distance. The entire system was installed after the ion-beam deceleration lens inside the large chamber of the bioengineering vertical ion beam line. Moving the measurement rod across the decelerated ion beam enabled to obtain beam profiles, from which the beam bending distance could be known and the ion beam energy could be calculated. The measurement results were in good agreement with theoretical and simulated results.

  14. A system for measuring the energy spread of an accelerated beam

    International Nuclear Information System (INIS)

    Wilkerson, J.F.; Ludwig, E.J.; Clegg, T.B.; Anderson, R.E.

    1987-01-01

    A system has been implemented to monitor directly the energy spread of analyzed beams from a tandem electrostatic accelerator. The dispersion of a deflection magnet in the beam handling system is used to transform the energy distribution into a spatial distribution, which then is measured by electrostatically sweeping the spatially extended beam across a narrow slit. (orig.)

  15. Fast and Precise Beam Energy Measurement using Compton Backscattering at e+e- Colliders

    CERN Document Server

    Kaminskiy, V V; Muchnoi, N Yu; Zhilich, V N

    2017-01-01

    The report describes a method for a fast and precise beam energy measurement in the beam energy range 0.5-2 GeV and its application at various e+e- colliders. Low-energy laser photons interact head-on with the electron or positron beam and produce Compton backscattered photons whose energy is precisely measured by HPGe detector. The method allows measuring the beam energy with relative accuracy of ∼2-5.10-5. The method was successfully applied at VEPP-4M, VEPP-3, VEPP-2000 (BINP, Russia) and BEPC-II (IHEP, China).

  16. Measurements of effective total macroscopic cross sections and effective energy of continuum beam

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Hisao [Rikkyo Univ., Yokosuka, Kanagawa (Japan). Inst. for Atomic Energy

    1998-03-01

    Two practically useful quantities are introduced in this study to characterize a continuum neutron beam and to describe transmission phenomena of the beam in field of quantitative neutron radiography: an effective energy instead of a peak energy or a mean energy of the spectrum and an effective total macroscopic (ETM) cross section instead of a total macroscopic (TM) cross section defined at the monochromatic energy. The effective energy was evaluated by means of energy dependence of ETM cross section. To realize the method a beam quality indicator (BQI) has been proposed recently. Several effective energies were measured for non-filtered, filtered neutron beams, and outputs of neutron guide tubes in world by the BQI. A thermal neutron beam and three beams modulated by Pb filters with different thicknesses are studied to measure ETM cross sections for various materials and summarized in a table. Validity of the effective energy determined by the BQI is discussed relating with ETM cross sections of materials. (author)

  17. DC proton beam measurements in a single-solenoid low-energy beam transport system

    International Nuclear Information System (INIS)

    Stevens, R.R. Jr.; Schafstall, P.; Schneider, J.D.; Sherman, J.; Zaugg, T.; Taylor, T.

    1994-01-01

    High current, CW proton accelerators are being considered for a number of applications including disposition of nuclear wastes, reduction of fissionable nuclear material inventories, safe production of critical nuclear materials, and energy production. All these applications require the development of high current, reliable, hydrogen ion injectors. In 1986, a program using CW RFQ technology was undertaken at CRL in collaboration with LANL and was continued there until 1993. During this time, an accelerator was built which produced 600 keV, 75 mA and 1,250 keV, 55 mA CW proton beams. The present program at Los Alamos using this accelerator is aimed at continuing the CRL work to demonstrate long-term reliability. In the present work, the authors are seeking to determine the optimal match to and the current limit of the 1,250-keV RFQ. This paper discusses the characterization of the 50 keV beams at the exit of the single-solenoid LEBT and presents both the experimental measurements and the beam simulations done to model this system

  18. Scintillation screen materials for beam profile measurements of high energy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Krishnakumar, Renuka

    2016-06-22

    For the application as a transverse ion beam diagnostics device, various scintillation screen materials were analysed. The properties of the materials such as light output, image reproduction and radiation stability were investigated with the ion beams extracted from heavy ion synchrotron SIS-18. The ion species (C, Ne, Ar, Ta and U) were chosen to cover the large range of elements in the periodic table. The ions were accelerated to the kinetic energies of 200 MeV/u and 300 MeV/u extracted with 300 ms pulse duration and applied to the screens. The particle intensity of the ion beam was varied from 10{sup 4} to 10{sup 9} particles per pulse. The screens were irradiated with typically 40 beam pulses and the scintillation light was captured using a CCD camera followed by characterization of the beam spot. The radiation hardness of the screens was estimated with high intensity Uranium ion irradiation. In the study, a linear light output for 5 orders of magnitude of particle intensities was observed from sensitive scintillators and ceramic screens such as Al{sub 2}O{sub 3}:Cr and Al{sub 2}O{sub 3}. The highest light output was recorded by CsI:Tl and the lowest one by Herasil. At higher beam intensity saturation of light output was noticed from Y and Mg doped ZrO{sub 2} screens. The light output from the screen depends not only on the particle intensity but also on the ion species used for irradiation. The light yield (i.e. the light intensity normalised to the energy deposition in the material by the ion) is calculated from the experimental data for each ion beam setting. It is shown that the light yield for light ions is about a factor 2 larger than the one of heavy ions. The image widths recorded exhibit a dependence on the screens material and differences up to 50 % were registered. On radiation stability analysis with high particle intensity of Uranium ions of about 6 x 10{sup 8} ppp, a stable performance in light output and image reproduction was documented from Al

  19. Beam Energy Measurement by Resonant Depolarization Method at VEPP-4M

    CERN Document Server

    Blinov, V E; Kaminskiy, V V; Kudryavtsev, V N; Nikitin, S A; Nikolaev, I B; Shekhtman, L I

    2017-01-01

    Experiments on high precision mass measurement of particles require precise beam energy calibration. The most accurate method of beam energy measurement is the resonant depolarization technique. This article describes the beam energy measurement at the VEPP-4M storage ring using this method together with a Touschek polarimeter. The accuracy achieved is about 10−6. More than thousand energy calibrations were used in the KEDR detector for the precise experiments on the measurement of J/ψ, ψ(2S), ψ(3770), D+, D0 meson and τ lepton masses.

  20. A calorimeter-Faraday cup to measure energy content of ion beams

    International Nuclear Information System (INIS)

    Luzzi, G.

    1984-01-01

    A calorimeter-Faraday cup to measure energy content of ion beams is described. It uses an HP quartz thermometer having a 10 -40 C sensitivity; contact potential problems, arising when working with thermocouples, are so avoided. Calibration has been performed with a resistive filament and with an electron beam. The apparatus is profitable if the measured ion beams are constant in time. The measured sensitivity was 10 -40 C/10 -5 W. (author)

  1. Test-beam programs for devices to measure luminosity and energy ...

    Indian Academy of Sciences (India)

    tem studies for luminosity and energy measurements and beam diagnostics for luminosity optimization. Keywords. ... tional information is obtained from a calorimeter measuring e+e− pairs produced by beamstrahlung ... (left); A diamond sensor of 10 × 10 mm2 size and 300 µm thickness assembled for the test-beam (right).

  2. Energy Deposition Simulations and Measurements in an LHC Collimator and Beam Loss Monitors

    CERN Document Server

    Böhlen, Till; Bracco, C; Dehning, B; Redaelli, S; Weiler, T; Zamantzas, C

    2010-01-01

    The LHC collimators are protected against beam-caused damages by measuring the secondary particle showers with beam loss monitors. Downstream of every collimator an ionisation chamber and a secondary emission monitor are installed to determine the energy deposition in the collimator. The relation between the energy deposition in the beam loss monitor and the collimator jaw is based on secondary shower simulations. To verify the FLUKA simulations, the prototype LHC collimator installed in the SPS was equipped with beam loss monitors. The results of the measurements of the direct impact of a 26 GeV proton beam injected in the SPS onto the collimator are compared with the predictions by FLUKA simulations. In addition, simulation results from parameter scans for mean and peak energy deposition with its dependencies are shown.

  3. Measurements of absorbed energy distributions in water from pulsed electron beams

    International Nuclear Information System (INIS)

    Devanney, J.A.

    1974-01-01

    An evaluation of the use of a holographic interferometer to measure the energy deposition as a function of depth in water from pulsed electron beams, together with a brief description of the interferometer and the technique of generating a hologram are presented. The holographic interferometer is used to measure the energy deposition as a function of depth in water from various pulsed beams of monoenergetic electrons in the energy range from 1.0 to 2.5 MeV. These results are compared to those computed by using a Monte Carlo radiation transport code, ETRAN-15, for the same electron energies. After the discrepancies between the measured and computed results are evaluated, reasonable agreement is found between the measured and computed absorbed energy distributions as a function of depth in water. An evalutation of the response of the interferometer as a function of electron intensities is performed. A comparison among four energy deposition curves that result from the irradiation of water with pulsed electron beams from a Febetron accelerator, model 705, is presented. These pulsed beams were produced by the same vacuum diode with the same charging voltage. The results indicate that the energy distribution of the electrons in the pulsed beam is not always constant. A comparison of the energy deposition curves that result from the irradiation of water with electron pulses from different vacuum diodes but the same charging voltage is presented. These results indicate again that the energy distribution of the electrons in the pulsed beam may vary between vacuum diodes. These differences would not be realized by using a totally absorbing metal calorimeter and Faraday Cup

  4. Measurement and Analysis of Rotational Energy of Nitrogen Molecular Beam by REMPI

    International Nuclear Information System (INIS)

    Mori, H.; Yamaguchi, H.; Kataoka, K.; Sugiyama, N.; Ide, K.; Niimi, T.

    2008-01-01

    Molecular beams are powerful tools for diagnoses of solid surfaces and gas-surface interaction tests. Unfortunately, there are very few reports about experimental analysis of internal energy distribution (e.g. rotational energy) of molecular beams of diatomic or polyatomic molecules, because measurement of internal energy distribution is very difficult. Spectroscopic measurement techniques based on resonantly enhanced multiphoton ionization (REMPI) is very powerful for measurement in highly rarefied gas flows. In this study, the REMPI method is applied to measurement of rotational energy distribution of nitrogen molecular beams. The REMPI spectrum of the molecular beam indicates the rotational temperature higher than the translational temperature of 7.2 K estimated by assuming isentropic flows. The O and P branches of the REMPI spectrum correspond to the rotational temperature of 30 K, but the S branch of the spectrum deviates from that at 30 K. It seems to be because the non-equilibrium rotational energy distribution of the molecular beam deviates from the Boltzmann distribution.

  5. Measurement of the BESSY II electron beam energy by Compton-backscattering of laser photons

    CERN Document Server

    Klein, R; Thornagel, R; Brandt, G; Görgen, R; Ulm, G

    2002-01-01

    Accurate knowledge of all storage ring parameters is essential for the Physikalisch-Technische Bundesanstalt (PTB) to operate the electron storage ring BESSY II as a primary source standard. One parameter entering the Schwinger equation for the calculation of the spectral photon flux of bending magnet radiation is the electron beam energy. So at BESSY II the electron beam energy is measured by two independent techniques one of which is described in this paper: the photons from a CO sub 2 -laser are scattered in a head-on collision with the stored electrons. From the spectrum of the backscattered photons that are detected by an energy-calibrated HPGe detector the electron beam energy can be determined. The experimental set-up at the BESSY II electron storage ring as well as the current experimental status are described for operation of the storage ring at the energies of 900 and 1700 MeV.

  6. Beam Diagnostics for Measurements of Antiproton Annihilation Cross Sections at Ultra-low Energy

    Directory of Open Access Journals (Sweden)

    Todoroki K.

    2014-03-01

    Full Text Available The ASACUSA (Atomic Spectroscopy And Collisions Using Slow Antiprotons collaboration of CERN is currently attempting to measure the antiproton-nucleus in-flight annihilation cross sections on thin target foils of C, Pd, and Pt at 130 keV of kinetic energy. The low-energy antiprotons were supplied by the Antiproton Decelerator (AD and a radio-frequency quadrupole decelerator. For this measurement, a beam profile monitor based on secondary electron emission was developed. Data from this monitor was used to ensure that antiprotons were precisely tuned to the position of an 80-mm-diameter experimental target, by measuring the spatial profile of 200-ns-long beam pulses containing 105 − 106 antiprotons with an active area of 40 mm × 40 mm and a spatial resolution of 4 mm. By using this monitor, we succeeded in finely tuning antiproton beams on the target, and observed some annihilation events originating from the target.

  7. Measurement of the beam energy of a cyclotron using a copper-foils technique

    International Nuclear Information System (INIS)

    Asad, A. H.; Price, Roger I.; Fleming, Adam; Burrage, John W.; Cryer, David; Chan, Sun; Deans, Tom; Saddiqui, Salim A.

    2009-01-01

    Full text: The 1 8 M eV cyclotron at SCGH (Perth) daily produces PET radioisotopes. An external beam line, incorporating an in-house designed target-holder, has been utilised to explore (p,x) solid targetry in the proton energy-range 7 -18 M eY. Some solid targetry techniques require a degrader for reducing beam energy. We investigated a technique to measure the proton-beam energy, with or without a degrader. Stacks of natural-copper (Cu) foils (31 % Cu-65, 69% Cu-63), purity >99.98% and thicknesses (l00, 75, 50 or 25/lm) were proton-bombarded in separate runs. In separate determinations for each run, activities of Zn-63, Zn-65 and (depending on beam energy) Zn-62 in each foil were then measured by HPGe -spectroscopy, and together with stopping-power and reaction-specific cross section data were used to calculate incident beam energy. Materials for a degrader were aluminium and graphite with calculated thicknesses of 0.920 and 1.128 m m, respectively, designed to reduce the energy from 1 8 M eV to I I A MeV, specifically to optimise the reaction Ni-64(p,n)Cu-64, currently under study in our laboratory. Beam energies thus derived from Zn-63 or Zn-65 had (eg; for thickness= I OO / lm) precision (+ 95%CI) of 7 -18 M eV, embracing production of a range of biomedically relevant isotopes such as 1-124, Zr-89 and Cu-64.

  8. Synchronous phase and energy measurement system for a 6.7-MeV H- beam

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.; Meyer, R.E.; Wells, F.D.; Power, J.F.; Shafer, R.E.

    1988-01-01

    A noninterceptive measurement system has been built to measure the energy and synchronous phase of a 6.7-MeV proton beam drifting from the ramped-gradient, drift-tube linac (RGDTL) in the accelerator test stand (ATS) facility. Axially-symmetric, capacitive probes used in these measurements produce signals that are proportional to the beam image current on their inner rings. Signals from two of these probes separated by 92.6 cm are down-converted from 425 to 20 MHz. The phase difference between these 20-MHz signals is then detected with an electronic, phase-comparator circuit. The phase-comparator signal output is a voltage that is related to momentum of the beam. A phase comparison is also provided between the 425-MHz fundamental rf field inside the RGDTL and the capacitive probe located nearest the RGDTL output. The total estimated error for the absolute and relative energy measurement is less than +- 12.2 and +- 3.1 keV, respectively. The total estimated error for the relative synchronous phase measurement is less than +-1/degree/. Beam energy versus synchronous phase experimental data agree with computer simulations. 3 refs., 3 figs., 1 tab

  9. 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.

  10. Beam emittance measurements in improving the energy resolution using an achromatic/dispersive system

    CERN Document Server

    Mohammadzadeh, A H; Afarideh, H; Haji-Saeid, S M; Aslani, G; 10.1016/S1350-4487(01)00270-0

    2002-01-01

    An achromatic/dispersive dual-purpose system is designed to transport the C-30 Cyclotron proton beam achromatically while it is capable of improving its energy resolution from 2*10/sup -2/ ( Delta E=600 keV) to about 10/sup -3/ ( Delta E=30 keV) at the Cyclotron Department, Nuclear Research Center for Agriculture and Medicine (NRCAM). A wire scanner was installed on the beam line to measure the proton beam profiles in both the transverse and longitudinal phase spaces. The beam matrix and its emittance were consequently deduced and used to find a satisfactory first-order solution to the problem using TRANSPORT code (Transport Appendix. Fermilab and CERN, Geneva, Switzerland, 1977). The necessary corrections to the second-order geometric and chromatic aberrations were incorporated by introducing sextupole components into the designed system as well as using TRANSPORT VARY CODE iteration method for further reduction of the induced aberrations. (8 refs).

  11. Summary of physics from measurements with longitudinally polarized beams and targets at ZGS energies

    Energy Technology Data Exchange (ETDEWEB)

    Yokosawa, A.

    1980-09-01

    An extensive amount of data were obtained from measurements of proton-proton elastic scattering from 1 to 12 GeV/c using longitudinally polarized beams and targets. Physics learned from these data as well as other related experimental results is summarized. The topics include structures observed in nucleon-nucleon scattering at lower energies and dinucleon resonances, pp scattering-amplitude measurements at 6 GeV/c, and lerge p/sub perpendicular/ results in pp elastic scattering.

  12. A new analysis technique to measure fusion excitation functions with large beam energy dispersions

    Science.gov (United States)

    Figuera, P.; Di Pietro, A.; Fisichella, M.; Lattuada, M.; Shotter, A. C.; Ruiz, C.; Zadro, M.

    2018-01-01

    Peculiar nuclear structures of two colliding nuclei such has clustering, neutron halo/skin or very low breakup thresholds can affect the reaction dynamics below the Coulomb barrier and this may also have astrophysical consequences. In order to have a better understanding of this topic, in the last decade, several experiments were performed. A typical experimental challenge of such studies is the need to measure excitation functions below the Coulomb barrier, having a strong energy dependence, with rather large beam energy dispersions inside the target. This may easily lead to ambiguities in associating the measured cross section with a proper beam energy. In this paper a discussion on this topic is reported and a new technique to deal with the above problem will be proposed.

  13. Measurement of residual radioactivity in cooper exposed to high energy heavy ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eunjoo; Nakamura, Takashi [Tohoku Univ., Sendai (Japan). Cyclotron and Radioisotope Center; Uwamino, Yoshitomo; Ito, Sachiko; Fukumura, Akifumi

    1999-03-01

    The residual radioactivities produced by high energy heavy ions have been measured using the heavy ion beams of the Heavy Ion Medical Accelerator (HIMAC) at National Institute of Radiological Sciences. The spatial distribution of residual radioactivities in 3.5 cm, 5.5 cm and 10 cm thick copper targets of 10 cm x 10 cm size bombarded by 290 MeV/u, 400 MeV/u-{sup 12}C ion beams and 400 MeV/u-{sup 20}Ne ion beam, respectively, were obtained by measuring the gamma-ray activities of 0.5 mm thick copper foil inserted in the target with a high purity Ge detector after about 1 hour to 6 hours irradiation. (author)

  14. Accelerator beam test of the kinematic lightweight energy meter detector prototype for very high energy cosmic ray measurements in space

    CERN Document Server

    Bashindzhagian, G L

    2004-01-01

    The idea of the KLEM (Kinematic Lightweight Energy Meter) detector is to directly measure the elemental energy spectra of very high-energy cosmic rays in space by determining the angular distribution of secondary particles produced in a target. The first test of the simple KLEM prototype was performed at the CERN SPS test-beam with 180 GeV pions. The results of the first test analysis confirm that, using the KLEM method, the energy of 180 GeV pions can be measured with a relative error of about 67%, which is very close to the results of the simulation (65 %).

  15. Instrumentation for EXELFS measurements using convergent beam diffraction coupling to the electron energy loss spectrometer

    International Nuclear Information System (INIS)

    Yuan Zou Wei; Csillag, S.; Tafreshi, M.A.

    1993-08-01

    Convergent beam diffraction coupling between a JEOL-100C scanning transmission microscope and an electron energy loss spectrometer is realised for the purpose of Extended Energy Loss Fine Structure (EXELFS) measurements. The working principle, the instrumentation for this coupling mode and some specific details, such as condenser system, shadow image, focusing conditions and measurement of convergent angles are described and discussed. The combination of a quadrupole and cylindrical lens for magnifying the image and increasing the dispersion of spectrum, together with a new type of compensation circuit for stray magnetic fields and the arrangement of the parallel recording system are also reported

  16. Measurement of breast tissue composition with dual energy cone-beam computed tomography: A postmortem study

    Energy Technology Data Exchange (ETDEWEB)

    Ding Huanjun; Ducote, Justin L.; Molloi, Sabee [Department of Radiological Sciences, University of California, Irvine, California 92697 (United States)

    2013-06-15

    Purpose: To investigate the feasibility of a three-material compositional measurement of water, lipid, and protein content of breast tissue with dual kVp cone-beam computed tomography (CT) for diagnostic purposes. Methods: Simulations were performed on a flat panel-based computed tomography system with a dual kVp technique in order to guide the selection of experimental acquisition parameters. The expected errors induced by using the proposed calibration materials were also estimated by simulation. Twenty pairs of postmortem breast samples were imaged with a flat-panel based dual kVp cone-beam CT system, followed by image-based material decomposition using calibration data obtained from a three-material phantom consisting of water, vegetable oil, and polyoxymethylene plastic. The tissue samples were then chemically decomposed into their respective water, lipid, and protein contents after imaging to allow direct comparison with data from dual energy decomposition. Results: Guided by results from simulation, the beam energies for the dual kVp cone-beam CT system were selected to be 50 and 120 kVp with the mean glandular dose divided equally between each exposure. The simulation also suggested that the use of polyoxymethylene as the calibration material for the measurement of pure protein may introduce an error of -11.0%. However, the tissue decomposition experiments, which employed a calibration phantom made out of water, oil, and polyoxymethylene, exhibited strong correlation with data from the chemical analysis. The average root-mean-square percentage error for water, lipid, and protein contents was 3.58% as compared with chemical analysis. Conclusions: The results of this study suggest that the water, lipid, and protein contents can be accurately measured using dual kVp cone-beam CT. The tissue compositional information may improve the sensitivity and specificity for breast cancer diagnosis.

  17. How to measure energy of LEReC electron beam with magnetic spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, S. [Brookhaven National Laboratory (BNL), Upton, NY (United States)

    2016-04-11

    For successful cooling the energies of RHIC ion beam and LEReC electron beam must be matched with 10-4 accuracy. While the energy of ions will be known with required accuracy, e-beam energy can have as large initial offset as 5%. The final setting of e-beam energy will be performed by observing either Schottky spectrum or recombination signal from debunched ions co-traveling with the e-beam. Yet, to start observing such signals one has to set absolute energy of electron beam with accuracy better than 10-2, preferably better than 5∙10-3. The aim of this exercise is to determine whether and how such accuracy can be reached by utilizing LEReC 180° bend as a spectrometer.

  18. Inverse Compton Scattering as a Diagnostic Tool for the Measurement of Electron Beam Energies in Diodes

    Science.gov (United States)

    Critchley, A. D. J.

    2003-10-01

    The main emphasis of the diode research project at the Atomic Weapons Establishment (AWE) UK is to produce small diameter radiographic spot sizes at high dose to improve the resolution of the transmission radiographs taken during hydrodynamic experiments. Experimental measurements of conditions within the diodes of Pulsed Power driven flash x-ray machines are vital to provide a benchmark for electromagnetic PIC codes such as LSP which are used to develop new diode designs. The potential use of inverse Compton scattering (ICS) as a diagnostic technique in the determination of electron energies within the diode has been investigated. The interaction of a laser beam with a beam of high-energy electrons will create an ICS spectrum of photons. Theoretically, one should be able to glean information on the energies and positions of the electrons from the energy spectrum and differential cross section of the scattered photons. The feasibility of fielding this technique on various diode designs has been explored, and an experimental setup with the greatest likelihood of success is proposed.

  19. A measurement of long-term energy stability of proton beam produced by Pelletron accelerator

    International Nuclear Information System (INIS)

    Takeda, Naoto; Hasegawa, Masataka; Kudo, Katsuhisa; Shimada, Makoto

    1997-01-01

    A 4 MV single-ended Van de Graaff ion accelerator (4UH-HC Pelletron from National Electrostatics Corp., USA) installed in 1982 has been used for various research fields of monoenergetic neutron fluence standards, creation and modification of new materials and material structure diagnostics by using ion beams. The accelerator was equipped with tank liner voltages stabilizer in 1993 in order to improve the terminal voltage stability to 0.01% for the ripple at 3 MV terminal voltage. Recently the power supply for an analyzing magnet located between the accelerator and a neutron producing target was replaced to obtain the better energy stability of 10 -6 . In this study, a long-term stability of proton energy, which is mainly affected by the drift of terminal voltage and the change of proton beam track from the ion source to the target, has been evaluated by measuring the change of neutron yield on the steeply changing lower energy portion of the resonance peak at 2.961 MeV from the Sc(p,n)Ti reaction. The result shows the energy spread (FWHM) to be less than 1.7 keV over 3 hour operation. (author)

  20. Ambient and Wake Turbulence Measurements at Marine Energy Sites from a Five Beam AD2CP

    Science.gov (United States)

    Guerra, M. A.; Thomson, J. M.

    2016-02-01

    Ambient turbulence at hydrokinetic energy sites is a key input for turbine design and for their performance determination. Added turbulence from rotating blades to the flow affects the environment surrounding the turbine and has an impact in turbine array distribution. We present two approaches of turbulence measurements: stationary and drifting. Stationary measurements allow for time and frequency analysis of turbulent velocities, while drifting measurements give a spatial characterization of turbulence. For both approaches we used the new five beam Nortek Signature AD2CP. This instrument captures turbulent flow along the water column at high sampling rates (8 Hz) with low Doppler noise level; the use of five beams also makes it possible to fully calculate the Reynolds Stresses. Both sets of measurements require Doppler noise removal for consistent results. Stationary measurements of ambient turbulence were carried out in Admiralty Inlet, WA, in May 2015. The Signature was deployed up looking on a sea spider tripod in a 50 m depth tidal channel during two tidal cycles. This data set allowed us to characterize the turbulence in terms of spectra and Reynolds Stresses in order to evaluate the turbulent kinetic energy balance along the water column and to compare results to other tidal energy sites with similar characteristics where turbulence measurements were taken as well. Drifting measurements of ambient and wake turbulence were conducted in the vicinity of the ORPC RivGen® turbine deployed on the Kvichak River in Alaska in July 2015. The Signature was mounted down looking onboard an anchor buoy equipped with two GPS data receivers for georefference. The cross-sectional river span was covered by releasing the drifter at different positions across the river. More than 300 drifts were performed to spatially characterize turbulence before and after turbine's deployment and grid connection. Results indicate an increased turbulent wake extending up to 75 m downstream

  1. Space Charge Correction on Emittance Measurement of Low Energy Electron Beams

    Energy Technology Data Exchange (ETDEWEB)

    Treado, Colleen J.; /Massachusetts U., Amherst

    2012-09-07

    The goal of any particle accelerator is to optimize the transport of a charged particle beam along a set path by confining the beam to a small region close to the design trajectory and directing it accurately along the beamline. To do so in the simplest fashion, accelerators use a system of magnets that exert approximately linear electromagnetic forces on the charged beam. These electromagnets bend the beam along the desired path, in the case of bending magnets, and constrain the beam to the desired area through alternating focusing and defocusing effects, in the case of quadrupole magnets. We can model the transport of such a beam through transfer matrices representing the actions of the various beamline elements. However, space charge effects, produced from self electric fields within the beam, defocus the beam and must be accounted for in the calculation of beam emittance. We present below the preliminary results of a MATLAB code built to model the transport of a charged particle beam through an accelerator and measure the emittance under the influence of space charge effects. We demonstrate the method of correctly calculating the emittance of a beam under space charge effects using a least square fit to determine the initial properties of the beam given the beam size measured at a specific point after transport.

  2. Asymmetry measurements in nucleon--nucleon scattering with polarized beams and targets at ZGS to Fermilab energies

    International Nuclear Information System (INIS)

    Yakosawa, A.

    1977-01-01

    Results of various asymmetry measurements in nucleon-nucleon scattering with polarized beams and targets at ZGS energies are presented. A possible direct-channel resonance in the pp system is discussed. Most of the discussion above ZGS energies are aimed at future measurements

  3. Metallic wedge degraders for rapid energy measurement of Bevalac heavy ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Wada, R.; Alonso, J.R.

    1981-03-01

    An ever-present need in an accelerator-based research program is knowing the energy of the beam delivered to the experimenter. Knowledge of accelerator parameters is generally good enough to predict the beam energy to within a few percent as it leaves the machine, but after passage through a complex switchyard, with air gaps, and non-destructive monitors, substantial changes in the energy can occur. Knowledge of the material in the beam path allows for calculations of expected energy loss, but this knowledge is not always complete, and the unforeseen often plays tricks on the unwary experimenter; for example, a section of beam-pipe inadvertently let up to air, or a monitor left in the beam-line from the previous run. Although such occurrences are rare, to say they do not happen would be grossly inaccurate. The only defense of the experimenter, then, is to have an accurate technique for determining the beam energy at his target location, a technique which requires little beam time and which is non-disruptive of his experimental setup. The device described meets all of these criteria, and is now used extensively in the Nuclear Science and Biomedical programs at the Bevalac.

  4. Metallic wedge degraders for rapid energy measurement of Bevalac heavy ion beams

    International Nuclear Information System (INIS)

    Wada, R.; Alonso, J.R.

    1981-03-01

    An ever-present need in an accelerator-based research program is knowing the energy of the beam delivered to the experimenter. Knowledge of accelerator parameters is generally good enough to predict the beam energy to within a few percent as it leaves the machine, but after passage through a complex switchyard, with air gaps, and non-destructive monitors, substantial changes in the energy can occur. Knowledge of the material in the beam path allows for calculations of expected energy loss, but this knowledge is not always complete, and the unforeseen often plays tricks on the unwary experimenter; for example, a section of beam-pipe inadvertently let up to air, or a monitor left in the beam-line from the previous run. Although such occurrences are rare, to say they do not happen would be grossly inaccurate. The only defense of the experimenter, then, is to have an accurate technique for determining the beam energy at his target location, a technique which requires little beam time and which is non-disruptive of his experimental setup. The device described meets all of these criteria, and is now used extensively in the Nuclear Science and Biomedical programs at the Bevalac

  5. A Computer Program to Measure the Energy Spread of Multi-turn Beam in the Fermilab Booster at Injection

    Science.gov (United States)

    Nelson, Jovan; Bhat, Chandrashekhara; Hendricks, Brian

    2016-03-01

    We have developed a computer program interfaced with the ACNET environment for Fermilab accelerators in order to measure the energy spread of the injected proton beam from the LINAC, at the energy of 400 MeV. This program allows the user to configure a digitizing oscilloscope and timing devices to optimize data acquisition from a resistive wall current monitor. When the program is launched, it secures control of the oscilloscope and then generates a ``one-shot'' timeline which initiates injection into the Booster. Once this is complete, a kicker is set to create a notch in the beam and the line charge distribution data is collected by the oscilloscope. The program then analyzes this data in order to obtain notch width, beam revolution period, and beam energy spread. This allows the program to be a possible useful diagnostic tool for the beginning of the acceleration cycle for the proton beam. Thank you to the SIST program at Fermilab.

  6. Application of a Low-Energy Electron Beam as a Tool for ultrashort bunch length measurement in circular machines

    CERN Document Server

    Nikiforov, D A; Malyutin, D; Matveenko, A; Rusinov, K; Starostenko, A A

    2017-01-01

    A new diagnostic device designed for non-destructive ultrashort bunch length measurement is described. The operating principle of the device and the measuring technique are described. The possible scheme of arrangement of the device elements are described. The results of simulations of EBP application for different beams under investigation are presented. The quality requirements of the low energy testing beam are considered and resolving detector ability is determined.

  7. Measurement of water decomposition products after the irradiation with high-energy heavy-ion beams

    International Nuclear Information System (INIS)

    Katsumura, Y.; Yamashita, S.; Muroya, Y.; Lin, M.; Miyazaki, T.; Kudo, H.; Murakami, T.

    2005-01-01

    We measured the G-values of water decomposition products produced by high-energy heavy-ion beams. It was found that the evaluated yields are consistent with reported ones. In other words, with the increase of LET, the radical yields decrease, and the molecular yields increase and tend to level off. But the evaluated yields are slightly higher than reported values. So we have started two trials. One is to check the values with experiment again, and the other is to explain the difference between the yields by using the spur diffusion model. In order to explain the values quantitatively, the spur diffusion model has been applied and track structure has been investigated. (author)

  8. Effects of energy chirp on bunch length measurement in linear accelerator beams

    Science.gov (United States)

    Sabato, L.; Arpaia, P.; Giribono, A.; Liccardo, A.; Mostacci, A.; Palumbo, L.; Vaccarezza, C.; Variola, A.

    2017-08-01

    The effects of assumptions about bunch properties on the accuracy of the measurement method of the bunch length based on radio frequency deflectors (RFDs) in electron linear accelerators (LINACs) are investigated. In particular, when the electron bunch at the RFD has a non-negligible energy chirp (i.e. a correlation between the longitudinal positions and energies of the particle), the measurement is affected by a deterministic intrinsic error, which is directly related to the RFD phase offset. A case study on this effect in the electron LINAC of a gamma beam source at the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) is reported. The relative error is estimated by using an electron generation and tracking (ELEGANT) code to define the reference measurements of the bunch length. The relative error is proved to increase linearly with the RFD phase offset. In particular, for an offset of {{7}\\circ} , corresponding to a vertical centroid offset at a screen of about 1 mm, the relative error is 4.5%.

  9. Simulation and measurement of the electrostatic beam kicker in the low-energy undulator test line

    International Nuclear Information System (INIS)

    Waldschmidt, G. J.

    1998-01-01

    An electrostatic kicker has been constructed for use in the Low-Energy Undulator Test Line (LEUTL) at the Advanced Photon Source (APS). The function of the kicker is to limit the amount of beam current to be accelerated by the APS linac. Two electrodes within the kicker create an electric field that adjusts the trajectory of the beam. This paper will explore the static fields that are set up between the offset electrode plates and determine the reaction of the beam to this field. The kicker was numerically simulated using the electromagnetic solver package MAFIA [1

  10. Online Measurement of the Energy Spread of Multi-Turn Beam in the Fermilab Booster at Injection

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, J. [Brown U.; Bhat, C. M. [Fermilab; Hendricks, B. S. [Fermilab

    2017-07-01

    We have developed a computer program interfaced with the ACNET environment of Fermilab accelerators to measure energy spread of the proton beam from the LINAC at an injection into the Booster. It uses a digitizing oscilloscope and provides users an ability to configure the scope settings for optimal data acquisition from a resistive wall current monitor. When the program is launched, a) a one shot timeline is generated to initiate beam injection into the Booster, b) a gap of about 40 ns is produced in the injected beam using a set of fast kickers, c) collects line charge distribution data from the wall current monitor for the first 200 μs from the injection and d) performs complete data analysis to extract full beam energy spread of the beam. The program also gives the option to store the data for offline analyses. We illustrate a case with an example. We also present results on beam energy spread as a function of beam intensity from recent measurements.

  11. Diamond detector in absorbed dose measurements in high-energy linear accelerator photon and electron beams.

    Science.gov (United States)

    Ravichandran, Ramamoorthy; Binukumar, John Pichy; Al Amri, Iqbal; Davis, Cheriyathmanjiyil Antony

    2016-03-08

    Diamond detectors (DD) are preferred in small field dosimetry of radiation beams because of small dose profile penumbras, better spatial resolution, and tissue-equivalent properties. We investigated a commercially available 'microdiamond' detector in realizing absorbed dose from first principles. A microdiamond detector, type TM 60019 with tandem electrometer is used to measure absorbed doses in water, nylon, and PMMA phantoms. With sensitive volume 0.004 mm3, radius 1.1mm, thickness 1 x10(-3) mm, the nominal response is 1 nC/Gy. It is assumed that the diamond detector could collect total electric charge (nC) developed during irradiation at 0 V bias. We found that dose rate effect is less than 0.7% for changing dose rate by 500 MU/min. The reproducibility in obtaining readings with diamond detector is found to be ± 0.17% (1 SD) (n = 11). The measured absorbed doses for 6 MV and 15 MV photons arrived at using mass energy absorption coefficients and stop-ping power ratios compared well with Nd, water calibrated ion chamber measured absorbed doses within 3% in water, PMMA, and nylon media. The calibration factor obtained for diamond detector confirmed response variation is due to sensitivity due to difference in manufacturing process. For electron beams, we had to apply ratio of electron densities of water to carbon. Our results qualify diamond dosimeter as a transfer standard, based on long-term stability and reproducibility. Based on micro-dimensions, we recommend these detectors for pretreatment dose verifications in small field irradiations like stereotactic treatments with image guidance.

  12. Measurement of the primary and scatter dose in high energy photon beams

    Energy Technology Data Exchange (ETDEWEB)

    Van der Linden, P.M. [Catharina Ziekenhuis, Eindhoven (Netherlands). Radiotherapy Dept.; Tiourina, T.B.; Dries, W.

    1995-12-01

    A method is presented to measure the primary and scatter components separately in a water tank using a small cylindrical absorber. Results from this experiment are compared with Monte Carlo calculations. The measurement setup consists of a small cylindrical absorber placed on a central axis of the beam a few centimetres above the radiation detector. Both absorber and detector move along the central axis while absorbed dose is registered. As the primary radiation is fully blocked, only scatter component is measured when a cylindrical absorber is used. Measurements in open fields result in the total absorbed dose being the sum of primary and scatter components. The primary dose component can be derived by substraction. Absorbers with different diameters are used. With decreasing dimensions the relative contribution of the dose due to scatter radiation increases. A steep increase is observed when the range of laterally scattered electrons becomes comparable with the radius of the absorber. Two different Monte Carlo simulations have been performed: with and without secondary electron transport. The data obtained for the former case perfectly agrees with the experiment. The situation where the secondary electron is assumed zero (i.e. local energy deposition) simulates the Cunningham model. Our results show that the Cunningham model predicts lower scatter component under the block edge which can be important for these applications.

  13. Precise and fast beam energy measurement at the international linear collider

    International Nuclear Information System (INIS)

    Viti, Michele

    2010-02-01

    The international Linear Collider (ILC) is an electron-positron collider with a center-of-mass energy between 200 and 500 GeV and a peak luminosity of 2 . 10 34 cm -2 s -1 . For the physics program at this machine, an excellent bunch-by-bunch control of the beam energy is mandatory. Several techniques are foreseen to be implemented at the ILC in order to achieve this request. Energy spectrometers upstream and downstream of the electron/positron interaction point were proposed and the present default option for the upstream spectrometer is a beam position monitor based (BPM-based) spectrometer. In 2006/2007, a prototype of such a device was commissioned at the End Station A beam line at the Stanford Linear Accelerator Center (SLAC) in order to study performance and reliability. In addition, a novel method based on laser Compton backscattering has been proposed, since as proved at the Large Electron-Positron Collider (LEP) and the Stanford Linear Collider (SLC), complementary methods are necessary to cross-check the results of the BPM-based spectrometer. In this thesis, an overview of the experiment at End Station A is given, with emphasis on the performance of the magnets in the chicane and first energy resolution estimations. Also, the novel Compton backscattering method is discussed in details and found to be very promising. It has the potential to bring the beam energy resolution well below the requirement of ΔE b /E b =10 -4 . (orig.)

  14. PIP-II Injector Test’s Low Energy Beam Transport: Commissioning and Selected Measurements

    Energy Technology Data Exchange (ETDEWEB)

    Shemyakin, A. [Fermilab; Alvarez, M. [Fermilab; Andrews, R. [Fermilab; Carneiro, J.-P. [Fermilab; Chen, A. [Fermilab; Hanna, B. [Fermilab; Prost, L. [Fermilab; Scarpine, V. [Fermilab; D' Arcy, R. [University Coll. London; Wiesner, C. [Goethe U., Frankfurt (main)

    2016-09-16

    The PIP2IT test accelerator is under construction at Fermilab. Its ion source and Low Energy Beam Transport (LEBT) in its initial (straight) configuration have been commissioned to full specification parameters. This paper introduces the LEBT design and summarizes the outcome of the commissioning activities.

  15. Precise and fast beam energy measurement at the international linear collider

    Energy Technology Data Exchange (ETDEWEB)

    Viti, Michele

    2010-02-15

    The international Linear Collider (ILC) is an electron-positron collider with a center-of-mass energy between 200 and 500 GeV and a peak luminosity of 2 . 10{sup 34} cm{sup -2}s{sup -1}. For the physics program at this machine, an excellent bunch-by-bunch control of the beam energy is mandatory. Several techniques are foreseen to be implemented at the ILC in order to achieve this request. Energy spectrometers upstream and downstream of the electron/positron interaction point were proposed and the present default option for the upstream spectrometer is a beam position monitor based (BPM-based) spectrometer. In 2006/2007, a prototype of such a device was commissioned at the End Station A beam line at the Stanford Linear Accelerator Center (SLAC) in order to study performance and reliability. In addition, a novel method based on laser Compton backscattering has been proposed, since as proved at the Large Electron-Positron Collider (LEP) and the Stanford Linear Collider (SLC), complementary methods are necessary to cross-check the results of the BPM-based spectrometer. In this thesis, an overview of the experiment at End Station A is given, with emphasis on the performance of the magnets in the chicane and first energy resolution estimations. Also, the novel Compton backscattering method is discussed in details and found to be very promising. It has the potential to bring the beam energy resolution well below the requirement of {delta}E{sub b}/E{sub b}=10{sup -4}. (orig.)

  16. Measurement profiles of nano-scale ion beam for optimized radiation energy losses

    International Nuclear Information System (INIS)

    Woo, T.H.; Cho, H.S.

    2011-01-01

    The behavior of charged particles is investigated for nano-scale ion beam therapy using a medical accelerator. Computational work is performed for the Bragg-peak simulation, which is focused on human organ material of pancreas and thyroid. The Results show that the trends of the dose have several different kinds of distributions. Before constructing a heavy ion collider, this study can give us the reliability of the therapeutic effect. Realistic treatment using human organs is calculated in a simple and cost effective manner using the computational code, the Stopping and Range of Ions in Matter 2008 (SRIM 2008). Considering the safety of the therapy, it is suggested to give a patient orient planning of the cancer therapy. The energy losses in ionization and phonon are analyzed, which are the behaviors in the molecular level nano-scopic investigation. The different fluctuations are shown at 150 MeV, where the lowest temperature is found in proton and pancreas case. Finally, the protocol for the radiation therapy is constructed by the simulation in which the procedure for a better therapy is selected. An experimental measurement incorporated with the simulations could be programmed by this protocol.

  17. The deflector-pickup system: A novel approach to measure online the energy spread of DC ion beams

    International Nuclear Information System (INIS)

    Bongardt, K.; Mitra, A.K.; Sauer, M.; Stockhorst, H.

    1990-01-01

    A new quite flexible system is proposed for measuring the energy spread of low velocity dc ion beams. The online detection can be done for different charge/mass ratios and variable particle energies. The ion current can be as low as 500 nA. All hardware components pertaining to the proposed measurement system do not interfere with the normal beam line operations. The major components of the system are a rf deflecting cavity and two rf pickups. By deflecting most of the beam to a limiting aperture a periodic pulse signal is created. With the pickups the voltage signal is measured at two different positions. The difference of the voltages which corresponds to a change of the pulse form is caused by the energy spread. The rms energy spread can be determined by reconstruction techniques from amplitude measurements of the Fourier components. The analysis is independent of the actual pulse shape and of pickup details. For a beam with β=3% or E=420 keV/N a detailed description of the complete system is presented. A prototype 20 MHz deflection cavity was built, where 25 W average power gave rise to 5 kV peak deflecting voltage sufficient for He + . With commercially available pickups, positioned 2 m apart, a rms energy spread of ±3x10 -3 can be detected. Two more ambitious designs are finally presented. One detects a rms energy spread of ±1x10 -3 . The other one is able to measure an energy spread of ±3x10 -3 for particle velocities varying from 3% to 6%. (orig.)

  18. Measurements of kQ beam quality correction factors for the NE2611A chamber in high-energy photon beams using the NMi water calorimeter

    International Nuclear Information System (INIS)

    Pieksma, M.; Prez, L.A. de; Dijk, E. van; Aalbers, A.H.L.

    2002-01-01

    electrometers) encountered in the Dutch and Belgian clinical practice. These k Q factors will be measured at selected institutes, covering representative beam qualities (and energies) and types of accelerator machines, using the portable NMi water calorimeter. The measurement program will involve the calibration of several sets of ionization chambers of types most commonly used in the radiotherapy institutes. These ionization chambers will first be calibrated in the NMi 60 Co beam directly against the water calorimeter, and then in situ in the selected radiotherapy beams, again directly against the water calorimeter. k Q factors are obtained as the ratios of calibration factors in high-energy beams to those in 60 Co. As a first test of the NMi water calorimeter in high-energy photon beams, measurements of absorbed dose-to-water rates were performed at the BNM-LNHB with a Saturne 43 accelerator for photon beam energies 6, 12, and 20 MeV. A set of 5 NE2611A chambers was calibrated against the water calorimeter at all three energies. This was done by calibrating the ionization chambers directly inside the water calorimeter phantom (obviously, with the glass sealed-water cell removed). Correction factors were measured for the attenuation by the glass cell, yielding 1.0020 at 6 MeV, 1.0012 at 12 MeV, and 1.0004 at 20 MeV. In addition, correction factors for polarity and recombination were determined at the three accelerator energies. k Q factors were derived from these calibration data in the high-energy beams and the absorbed-dose-to-water calibration factors of the NE2611A chambers in the NMi 60 Co beam, that had already been established. These k Q factors have to be considered as preliminary, since the experiment suffered from pick-up of noise on the thermistor probe cables, most likely induced by the HF-generator of the Saturne 43 accelerator. This experiment will therefore be repeated to establish a set of accurate reference k Q factors for the NE2611A chambers. A detailed

  19. Measurement of the spectrum of neutrons produced in pd collisions at an angle of θ = 0° at a proton-beam energy of 1 GeV

    Science.gov (United States)

    Medvedev, V. I.; Vasiliev, A. A.; Ermakov, K. N.; Koptev, V. P.; Kochenda, L. M.; Poromov, V. I.; Rogachevsky, O. V.; Sarantsev, V. V.; Trofimov, V. A.; Sherman, S. G.

    2009-09-01

    The energy spectrum of a neutron beam produced in a thin-wall liquid-deuterium target by a proton beam of energy 1 GeV was measured in a hydrogen bubble chamber by detecting events of the reaction np → ppπ -.

  20. Beam position monitor for energy recovered linac beams

    Energy Technology Data Exchange (ETDEWEB)

    Powers, Thomas; Evtushenko, Pavel

    2017-06-06

    A method of determining the beam position in an energy recovered linac (ERL). The method makes use of in phase and quadrature (I/Q) demodulation techniques to separate the pickup signal generated by the electromagnetic fields generated by the first and second pass beam in the energy recovered linac. The method includes using analog or digital based I/Q demodulation techniques in order to measure the relative amplitude of the signals from a position sensitive beam pickup such as a button, strip line or microstripline beam position monitor.

  1. Test-beam programs for devices to measure luminosity and energy ...

    Indian Academy of Sciences (India)

    addition, to tune the beams to highest luminosity within a bunch train a fast feedback system based on highly precise ... The average beam momentum will be determined by the deflection in a magnetic field. A magnet chicane consisting of four dipole magnets, as shown in figure 2a, will be used. The position of the beam is ...

  2. In-phantom measurement of absorbed dose to water in medium energy x-ray beams

    International Nuclear Information System (INIS)

    Hohlfeld, K.

    1996-01-01

    Absorbed dose values in a water phantom derived by the formalism of the IAEA Code of Practice of Absorbed Dose Determination in Photon and Electron Beams are a few per cent higher than those based on the procedure following e.g. ICRU Report 23. The maximum deviation exceeds 10% at 100 kV tube potential. The correction factor needed to take into account the differences at the calibration in terms of air kerma free in air and at the measurement in the water phantom can be determined in different ways: In comparing the result of the absorbed dose measurement by means of the ionization chambers with an other, preferably fundamental method of measurement of absorbed dose in the water phantom or by evaluating all component parts of the correction factor separately. The values of the perturbation correction factor in the IAEA Code were determined in the former way by comparing against a graphite extrapolation chamber. A review is given on a recent re-evaluation using former values of the extrapolation chamber measurements and on new determinations using an absorbed dose water calorimeter, a method based on calculated and measured air kerma values and a method of combining the component factors to the overall correction factor. Recent results achieved by the different methods are compared and a change of the data of the IAEA Code is recommended. (author). 31 refs, 14 figs, 3 tabs

  3. A Bench Measurement of the Energy Loss of a Stored Beam to a Cavity

    Energy Technology Data Exchange (ETDEWEB)

    Sands, M; Rees, J.; /SLAC

    2016-12-19

    A rather simple electronic bench experiment is proposed for obtaining a measure of the impulse energy loss of a stored particle bunch to an rf cavity or other vacuum-chamber structure--the so-called "cavity radiation". The proposed method is analyzed in some detail.

  4. Beam-energy and laser beam-profile monitor at the BNL LINAC

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, R.; Briscoe, B.; Degen, C.; DeSanto, L.; Meng, W.; Minty, M.; Nayak, S.; Raparia, D.; Russo, T.

    2010-05-02

    We are developing a non-interceptive beam profile and energy monitor for H{sup -} beams in the high energy beam transport (HEBT) line at the Brookhaven National Lab linac. Electrons that are removed from the beam ions either by laser photodetachment or stripping by background gas are deflected into a Faraday cup. The beam profile is measured by stepping a narrow laser beam across the ion beam and measuring the electron charge vs. transverse laser position. There is a grid in front of the collector that can be biased up to 125kV. The beam energy spectrum is determined by measuring the electron charge vs. grid voltage. Beam electrons have the same velocity as the beam and so have an energy of 1/1836 of the beam protons. A 200MeV H{sup -} beam yields 109keV electrons. Energy measurements can be made with either laser-stripped or gas-stripped electrons.

  5. H- beam neutralization measurements in a solenoidal beam transport system

    International Nuclear Information System (INIS)

    Sherman, J.; Pitcher, E.; Stevens, R.; Allison, P.

    1992-01-01

    H minus beam space-charge neutralization is measured for 65-mA, 35-keV beams extracted from a circular-aperture Penning surface-plasma source, the small-angle source. The H minus beam is transported to a RFQ matchpoint by a two-solenoid magnet system. Beam noise is typically ±4%. A four-grid analyzer is located in a magnetic-field-free region between the two solenoid magnets. H minus potentials are deduced from kinetic energy measurements of particles (electrons and positive ions) ejected radially from the beam channel by using a griddled energy analyzer. Background neutral gas density is increased by the introduction of additional Xe and Ar gases, enabling the H minus beam to become overneutralized

  6. Current and turbulence measurements at the FINO1 offshore wind energy site: analysis using 5-beam ADCPs

    Science.gov (United States)

    Bakhoday-Paskyabi, Mostafa; Fer, Ilker; Reuder, Joachim

    2018-01-01

    We report concurrent measurements of ocean currents and turbulence at two sites in the North Sea, one site at upwind of the FINO1 platform and the other 200-m downwind of the Alpha Ventus wind farm. At each site, mean currents, Reynolds stresses, turbulence intensity and production of turbulent kinetic energy are obtained from two bottom-mounted 5-beam Nortek Signature1000s, high-frequency Doppler current profiler, at a water depth of approximately 30 m. Measurements from the two sites are compared to statistically identify the effects of wind farm and waves on ocean current variability and the turbulent structure in the water column. Profiles of Reynolds stresses are found to be sensible to both environmental forcing and the wind farm wake-induced distortions in both boundary layers near the surface and the seabed. Production of turbulent kinetic energy and turbulence intensity exhibit approximately similar, but less pronounced, patterns in the presence of farm wake effects.

  7. Comparison of film measurements and Monte Carlo simulations of dose delivered with very high-energy electron beams in a polystyrene phantom.

    Science.gov (United States)

    Bazalova-Carter, Magdalena; Liu, Michael; Palma, Bianey; Dunning, Michael; McCormick, Doug; Hemsing, Erik; Nelson, Janice; Jobe, Keith; Colby, Eric; Koong, Albert C; Tantawi, Sami; Dolgashev, Valery; Maxim, Peter G; Loo, Billy W

    2015-04-01

    To measure radiation dose in a water-equivalent medium from very high-energy electron (VHEE) beams and make comparisons to Monte Carlo (MC) simulation results. Dose in a polystyrene phantom delivered by an experimental VHEE beam line was measured with Gafchromic films for three 50 MeV and two 70 MeV Gaussian beams of 4.0-6.9 mm FWHM and compared to corresponding MC-simulated dose distributions. MC dose in the polystyrene phantom was calculated with the EGSnrc/BEAMnrc and DOSXYZnrc codes based on the experimental setup. Additionally, the effect of 2% beam energy measurement uncertainty and possible non-zero beam angular spread on MC dose distributions was evaluated. MC simulated percentage depth dose (PDD) curves agreed with measurements within 4% for all beam sizes at both 50 and 70 MeV VHEE beams. Central axis PDD at 8 cm depth ranged from 14% to 19% for the 5.4-6.9 mm 50 MeV beams and it ranged from 14% to 18% for the 4.0-4.5 mm 70 MeV beams. MC simulated relative beam profiles of regularly shaped Gaussian beams evaluated at depths of 0.64 to 7.46 cm agreed with measurements to within 5%. A 2% beam energy uncertainty and 0.286° beam angular spread corresponded to a maximum 3.0% and 3.8% difference in depth dose curves of the 50 and 70 MeV electron beams, respectively. Absolute dose differences between MC simulations and film measurements of regularly shaped Gaussian beams were between 10% and 42%. The authors demonstrate that relative dose distributions for VHEE beams of 50-70 MeV can be measured with Gafchromic films and modeled with Monte Carlo simulations to an accuracy of 5%. The reported absolute dose differences likely caused by imperfect beam steering and subsequent charge loss revealed the importance of accurate VHEE beam control and diagnostics.

  8. Measuring Dirac CP-violating phase with intermediate energy beta beam facility

    Science.gov (United States)

    Bakhti, P.; Farzan, Y.

    2014-02-01

    Taking the established nonzero value of , we study the possibility of extracting the Dirac CP-violating phase by a beta beam facility with a boost factor . We compare the performance of different setups with different baselines, boost factors, and detector technologies. We find that an antineutrino beam from He decay with a baseline of km has a very promising CP-discovery potential using a 500 kton water Cherenkov detector. Fortunately this baseline corresponds to the distance between FermiLAB to Sanford underground research facility in South Dakota.

  9. Neutron beam measurement dosimetry

    International Nuclear Information System (INIS)

    Amaro, C.R.

    1995-01-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR

  10. First results from the microwave air yield beam experiment (MAYBE): Measurement of GHz radiation for ultra-high energy cosmic ray detection

    Energy Technology Data Exchange (ETDEWEB)

    Williams, C. [Chicago U., KICP; Bohacova, M. [Prague, Inst. Phys.; Bonifazi, C. [Rio de Janeiro Federal U.; Cataldi, G. [INFN, Lecce; Chemerisov, S. [Argonne (main); De Mello Neto, J. R.T. [INFN, Lecce; Facal San Luis, P. [Chicago U., KICP; Fox, B. [Hawaii U.; Gorham, P. W. [Hawaii U.; Hojvat, C. [Fermilab; Hollon, N. [Chicago U., KICP; Meyhandan, R. [Hawaii U.; Monasor, M. [Chicago U., KICP; D' Orfeuil, B. Rouille [Chicago U., KICP; Santos, E. M. [Rio de Janeiro Federal U.; Pochez, J. [Chicago U., KICP; Privitera, P. [Chicago U., KICP; Spinka, H. [Argonne (main); Verzi, V. [Rome U., Tor Vergata; Zhou, J. [Chicago U., KICP

    2013-01-01

    We present measurements of microwave emission from an electron-beam induced air plasma performed at the 3 MeV electron Van de Graaff facility of the Argonne National Laboratory. Results include the emission spectrum between 1 and 15 GHz, the polarization of the microwave radiation and the scaling of the emitted power with respect to beam intensity. MAYBE measurements provide further insight on microwave emission from extensive air showers as a novel detection technique for Ultra-High Energy Cosmic Rays.

  11. Measurements of the Influence of Thermoplastic Mask in High Energy Photon Beams: Gel Dosimeter or Ionizing Chamber?

    Science.gov (United States)

    Moreira, M. V.; Petchevist, C. D.; de Almeida, A.

    2009-12-01

    The influence of the immobilization mask material on the absorbed dose distribution in patients exposed to radiotherapy treatment with photon beams has been investigated for photons from a 60Co source and a 6 MV Linac. Absorbed dose values have been inferred at different depths and in the build-up region. Dose measurements were obtained using Fricke Xylenol Gel dosimeter and the cylindrical PTW Freiburg TM 31016-0.016 cc ionizing micro chamber; their discrepancies are discussed. The affinities of FXG and PTW ICMicro for measurements with high energy photons and the difference in the effective atomic numbers due to their compositions are most likely the most important factors that contribute to the measured dose in the build-up region. The measured values show that the use of the mask material contributes to increase the absorbed doses near the surface of the tissue. The result also shows that the build-up effect for 60Co is significantly smaller than that for 6 MV photons; however, the variations noted in the final doses of the radiotherapic treatments with photons of high energy do not represent alterations in the total doses received by the patients submitted to the radiotherapy.

  12. Measurements of thermal- and slow-neutron dose distributions in ordinary concrete shield using a reactor neutron beam of different energy ranges

    Energy Technology Data Exchange (ETDEWEB)

    Megahid, R.M.; Makarious, A.S.; El-Kolaly, M.A.; Afifi, Y.A.

    1980-01-01

    Experimental studies on the distribution and attenuation of thermal and slow neutron doses in ordinary concrete shield have been carried-out. A collimated beam of reactor neutrons emitted from one of the horizontal channels of the ET-RR-1 reactor was used. Measurements were performed using, a direct beam, cadmium filtered beam and boron carbide filtered beam. The neutron doses were measured using thermolumin-escent Li/sub 2/B/sub 4/O/sub 7/ detectors. The measured data have been analyzed and a group of attenuation curves were given for beams of reactor neutrons of different energy. These curves show that cadmium and boron carbide filters tend to decrease the neutron doses specially at the beginning of penetration. The data were transformed to that which would be obtained using neutron sources of different geometries.

  13. A method for measuring coherent elastic neutrino-nucleus scattering at a far off-axis high-energy neutrino beam target

    Energy Technology Data Exchange (ETDEWEB)

    Brice, S. J. [Fermilab; Cooper, R. L. [Indiana U.; DeJongh, F. [Fermilab; Empl, A. [Houston U.; Garrison, L. M. [Indiana U.; Hime, A. [Los Alamos; Hungerford, E. [Houston U.; Kobilarcik, T. [Fermilab; Loer, B. [Fermilab; Mariani, C. [Virginia Tech.; Mocko, M. [Los Alamos; Muhrer, G. [Los Alamos; Pattie, R. [North Carolina State U.; Pavlovic, Z. [Los Alamos; Ramberg, E. [Fermilab; Scholberg, K. [Duke U.; Tayloe, R. [Indiana U.; Thornton, R. T. [Indiana U.; Yoo, J. [Fermilab; Young, A. [North Carolina State U.

    2014-04-03

    We present an experimental method for measuring the process of coherent elastic neutrino-nucleus scattering (CENNS). This method uses a detector situated transverse to a high-energy neutrino beam production target. This detector would be sensitive to the low-energy neutrinos arising from decay-at-rest pions in the target. We discuss the physics motivation for making this measurement and outline the predicted backgrounds and sensitivities using this approach. We report a measurement of neutron backgrounds as found in an off-axis surface location of the Fermilab Booster Neutrino Beam (BNB) target. The results indicate that the Fermilab BNB target is a favorable location for a CENNS experiment.

  14. Energy spectrum control for modulated proton beams

    International Nuclear Information System (INIS)

    Hsi, Wen C.; Moyers, Michael F.; Nichiporov, Dmitri; Anferov, Vladimir; Wolanski, Mark; Allgower, Chris E.; Farr, Jonathan B.; Mascia, Anthony E.; Schreuder, Andries N.

    2009-01-01

    In proton therapy delivered with range modulated beams, the energy spectrum of protons entering the delivery nozzle can affect the dose uniformity within the target region and the dose gradient around its periphery. For a cyclotron with a fixed extraction energy, a rangeshifter is used to change the energy but this produces increasing energy spreads for decreasing energies. This study investigated the magnitude of the effects of different energy spreads on dose uniformity and distal edge dose gradient and determined the limits for controlling the incident spectrum. A multilayer Faraday cup (MLFC) was calibrated against depth dose curves measured in water for nonmodulated beams with various incident spectra. Depth dose curves were measured in a water phantom and in a multilayer ionization chamber detector for modulated beams using different incident energy spreads. Some nozzle entrance energy spectra can produce unacceptable dose nonuniformities of up to ±21% over the modulated region. For modulated beams and small beam ranges, the width of the distal penumbra can vary by a factor of 2.5. When the energy spread was controlled within the defined limits, the dose nonuniformity was less than ±3%. To facilitate understanding of the results, the data were compared to the measured and Monte Carlo calculated data from a variable extraction energy synchrotron which has a narrow spectrum for all energies. Dose uniformity is only maintained within prescription limits when the energy spread is controlled. At low energies, a large spread can be beneficial for extending the energy range at which a single range modulator device can be used. An MLFC can be used as part of a feedback to provide specified energy spreads for different energies.

  15. An introduction to cross-sections and asymmetries measurable using polarised beams in high-energy e+e- colliders

    International Nuclear Information System (INIS)

    Clarke, P.

    1990-08-01

    The implementation of polarised beams at SLC, and hopefully LEP, is an important development. This will allow access to a range of precision measurements which exploit the parity violating nature of the Z boson. This report gives an introduction to the basic quantities which may be measured with polarised beams. These are the left-right asymmetry (A LR ), forward-backward asymmetries with and without polarisation (A R FB , A L FB , A FB ) and the ''improved'' polarised forward-backward asymmetry (A pol FB ). The final state polarisation measurement is also discussed. (author)

  16. High-energy in-beam neutron measurements of metal-based shielding for accelerator-driven spallation neutron sources

    Science.gov (United States)

    DiJulio, D. D.; Cooper-Jensen, C. P.; Björgvinsdóttir, H.; Kokai, Z.; Bentley, P. M.

    2016-05-01

    Metal-based shielding plays an important role in the attenuation of harmful and unwanted radiation at an accelerator-driven spallation neutron source. At the European Spallation Source, currently under construction in Lund, Sweden, metal-based materials are planned to be used extensively as neutron guide substrates in addition to other shielding structures around neutron guides. The usage of metal-based materials in the vicinity of neutron guides however requires careful consideration in order to minimize potential background effects in a neutron instrument at the facility. Therefore, we have carried out a combined study involving high-energy neutron measurements and Monte Carlo simulations of metal-based shielding, both to validate the simulation methodology and also to investigate the benefits and drawbacks of different metal-based solutions. The measurements were carried out at The Svedberg Laboratory in Uppsala, Sweden, using a 174.1 MeV neutron beam and various thicknesses of aluminum-, iron-, and copper-based shielding blocks. The results were compared to geant4 simulations and revealed excellent agreement. Our combined study highlights the particular situations where one type of metal-based solution may be preferred over another.

  17. Overview of LHC Beam Loss Measurements

    CERN Document Server

    Dehning, B; Effinger, E; Emery, J; Fadakis, E; Holzer, E B; Jackson, S; Kruk, G; Kurfuerst, C; Marsili, A; Misiowiec, M; Nebot Del Busto, E; Nordt, A; Priebe, A; Roderick, C; Sapinski, M; Zamantzas, C; Grishin, V; Griesmayer, E

    2011-01-01

    The LHC beam loss monitoring system provides measurements with an update rate of 1 Hz and high time resolution data by event triggering. These informations are used for the initiation of beam aborts, fixed displays and the off line analysis. The analysis of fast and localized loss events resulted in the determination of its rate, duration, peak amplitudes, its scaling with intensity, number of bunches and beam energy. The calibration of the secondary shower beam loss signal in respect to the needed beam energy deposition to quench the magnet coil is addressed at 450GeV and 3.5T eV . The adjustment of collimators is checked my measuring the loss pattern and its variation in the collimation regions of the LHC. Loss pattern changes during a fill allow the observation of non typical fill parameters.

  18. Medium-Term Stability of the Photon Beam Energy of An Elekta CompactTM Linear Accelerator Based on Daily Measurements of Beam Quality Factor

    Directory of Open Access Journals (Sweden)

    Mohammad Amin Mosleh-Shirazi

    2016-04-01

    Full Text Available Introduction In this study, we aimed to assess the medium-term energy stability of a 6MV Elekta CompactTM linear accelerator. To the best of our knowledge, this is the first published article to evaluate this linear accelerator in terms of energy stability. As well as investigating the stability of the linear accelerator energy over a period of several weeks, the results will be useful for estimation of the required tolerance values for the beam quality factor (BQF of the PTW QUICKCHECK weblineTM (QCW daily checking device. Materials and Methods Over a 13 week period of routine clinical service, 52 daily readings of BQF were taken and then analyzed for a 10×10 cm2 field. Results No decreasing or increasing trend in BQF was observed over the study period. The mean BQF value was estimated at 5.4483 with a standard deviation (SD of 0.0459 (0.8%. The mean value was only 0.1% different from the baseline value. Conclusion The results of this medium-term stability study of the Elekta Compact linear accelerator energy showed that 96.2% of the observed BQF values were within ±1.3% of the baseline value. This can be considered to be within the recommended tolerance for linear accelerator photon beam energy. If an approach of applying ±3 SD is taken, the tolerance level for BQF may be suggested to be set at ±2.5%. However, further research is required to establish a relationship between BQF value and the actual changes in beam energy and penetrative quality.

  19. Beam lifetime measurement and analysis in Indus-2 electron ...

    Indian Academy of Sciences (India)

    In this paper, the beam lifetime measurement and its theoretical analysis are presented using measured vacuum pressure and applied radio frequency (RF) cavity voltage in Indus-2 electron storage ring at 2 GeV beam energy. Experimental studies of the effect of RF cavity voltage and bunched beam filling pattern on beam ...

  20. Performance evaluation of one-dimensional fiber-optic radiation sensor for measuring high energy electron beam using a charge-coupled device

    International Nuclear Information System (INIS)

    Cho, Dong Hyun; Jang, Kyoung Won; Yoo, Wook Jae; Chung, Soon Cheol; Tack, Gye Rae; Eom, Gwang Moon; Lee, Bongsoo; Cho, Hyosung; Kim, Sin

    2008-01-01

    In this study, we have fabricated one-dimensional fiber-optic radiation sensor array for high energy electron beam therapy dosimetry. Fiber-optic radiation sensor comprises an organic scintillator as a sensing volume, optical fiber as a light guider and photo-detector as a light measuring device. Usually, photomultiplier tube or photodiode is used as a photo-detector however we have tried to use a charge-coupled device as a scintillating light measuring system for one-dimensional fiber-optic radiation sensor array. This system can take an image of the proximal ends of one-dimensional fiber-optic sensor array and can measure light intensities of individual image of optical fibers simultaneously using simple imaging software. Charge-coupled device as a light measuring detector has many advantages which are easy in multi-dimensional measurements, high spatial resolution and relatively low cost. We have measured one-dimensional electron beam distributions in a PMMA phantom with different energies and field sizes of electron beam using a fiber-optic sensor and a charge-coupled device. Also, the percentage depth dose curves for high energy electron beams are obtained. (author)

  1. Quality indexes based on water measurements for low and medium energy x-ray beams: A theoretical study with PENELOPE

    Energy Technology Data Exchange (ETDEWEB)

    Chica, U. [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada, Spain and FISRAD S.A.S Carrera 64 a No 22-41, Bogotá D.C. (Colombia); Anguiano, M.; Lallena, A. M., E-mail: lallena@ugr.es [Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, E-18071 Granada (Spain); Vilches, M. [Servicio de Radiofísica, Hospital Universitario “San Cecilio”, Avda. Dr. Olóriz, 16, E-18012 Granada (Spain)

    2014-01-15

    Purpose : To study the use of quality indexes based on ratios of absorbed doses in water at two different depths to characterize x-ray beams of low and medium energies. Methods : A total of 55 x-ray beam spectra were generated with the codes XCOMP5R and SPEKCALC and used as input of a series of Monte Carlo simulations performed with PENELOPE, in which the percentage depth doses in water and thek{sub Q,Q{sub 0}} factors, defined in the TRS-398 protocol, were determined for each beam. Some of these calculations were performed by simulating the ionization chamber PTW 30010. Results : The authors found that the relation betweenk{sub Q,Q{sub 0}} and the ratios of absorbed doses at two depths is almost linear. A set of ratios statistically compatible with that showing the best fit has been determined. Conclusions : The results of this study point out which of these ratios of absorbed doses in water could be used to better characterize x-ray beams of low and medium energies.

  2. Transverse beam shape measurements of intense proton beams using optical transition radiation

    Energy Technology Data Exchange (ETDEWEB)

    Scarpine, Victor E.; /Fermilab

    2012-03-01

    A number of particle physics experiments are being proposed as part of the Department of Energy HEP Intensity Frontier. Many of these experiments will utilize megawatt level proton beams onto targets to form secondary beams of muons, kaons and neutrinos. These experiments require transverse size measurements of the incident proton beam onto target for each beam spill. Because of the high power levels, most beam intercepting profiling techniques will not work at full beam intensity. The possibility of utilizing optical transition radiation (OTR) for high intensity proton beam profiling is discussed. In addition, previous measurements of OTR beam profiles from the NuMI beamline are presented.

  3. Noninterceptive transverse-beam measurements

    International Nuclear Information System (INIS)

    Chamberlin, D.D.; Minerbo, G.N.; Mottershead, C.T.

    1981-01-01

    Totally noninterceptive techniques for accurate measurement of transverse beam distributions are required for high-current continuous wave (cw) linacs, such as the Fusion Materials Irradiation Test (FMIT) accelerator. Sensors responding to visible radiation from beam interactions with residual gas and computer algorithms reconstructing spatial and phase space distributions have been implemented. This paper reports on early measurements of the beam from the injector of the prototype FMIT facility at Los Alamos. The first section indicates hardware setup and performance whereas the second section describes the data-processing software. The third section outlines the resultant measurements and further developments are discussed in the fourth section

  4. Impact of beam-beam effects on precision luminosity measurements at the ILC

    CERN Document Server

    Rimbault, C; Mönig, K; Schulte, D

    2007-01-01

    In this paper, the impact of beam-beam effects on the precision luminosity measurement at the International Linear Collider is investigated quantitatively for the first time. GUINEA-PIG, a beam-beam interaction simulation tool, is adapted to treat the space charge effects affecting the Bhabha events used in this measurement. The biases due to the resulting changes in kinematics are evaluated for different center-of-mass energies and beam parameters.

  5. Beam emittance measurements on multicusp ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Sarstedt, M.; Lee, Y.; Leung, K.N. [and others

    1995-08-01

    Multicusp ion sources are used for various applications. Presently, the implementation of this type of ion source planned for the development of an ion beam lithography machine, which will be used for the projection of sub-0.2 {mu}m patterns onto a wafer substrate. Since, for this application, a very good beam quality and a small ion energy spread are required, emittance measurements have been performed on a multicusp ion source for various source conditions. It is shown that the installation of proper capacitors between the extraction electrodes is necessary to avoid rf-pickup, which otherwise leads to a distortion of the beam emittance. The influence of the magnetic filter field on the beam emittance has been investigated, and the beam emittance of a dc filament-discharge plasma has also been compared to that of an rf-generated plasma.

  6. Beam emittance measurements on multicusp ion sources

    International Nuclear Information System (INIS)

    Sarstedt, M.; Lee, Y.; Leung, K.N.

    1995-08-01

    Multicusp ion sources are used for various applications. Presently, the implementation of this type of ion source planned for the development of an ion beam lithography machine, which will be used for the projection of sub-0.2 μm patterns onto a wafer substrate. Since, for this application, a very good beam quality and a small ion energy spread are required, emittance measurements have been performed on a multicusp ion source for various source conditions. It is shown that the installation of proper capacitors between the extraction electrodes is necessary to avoid rf-pickup, which otherwise leads to a distortion of the beam emittance. The influence of the magnetic filter field on the beam emittance has been investigated, and the beam emittance of a dc filament-discharge plasma has also been compared to that of an rf-generated plasma

  7. Specialized beam diagnostic measurements for an ADTT accelerator funnel

    International Nuclear Information System (INIS)

    Gilpatrick, John Douglas

    1995-01-01

    Los Alamos National Laboratory has proposed several CW-proton-beam facilities for accelerator-driven transmutation technologies (ADTT) with beam-current densities greater than 5 mA/mm 2 . The primary beam-diagnostics-instrumentation requirement for these facilities is to provide sufficient beam information to understand and minimize beam-loss. To accomplish this task, the beam diagnostics instrumentation must measure beam parameters such as the projected centroids and profiles, total integrated current, and particle loss. Because of the high specific energy loss in materials at beam energies less than 20 MeV, interceptive measurements such as wire scanners or fluors cannot be used to determine beam profiles or centroids. Therefore, noninterceptive techniques must be used for on-line diagnosis of high-intensity CW beam at low energies. The beam funnel area of these proposed accelerator facilities provide a particular interesting beam measurement challenge. In this area of the accelerator, beam measurements must also sense how well the two funnel input-beams are matched to each other in phase space. This paper will discuss some of the measurement requirements for these proposed accelerator facilities and the various noninterceptive techniques to measure dual-beam funnel operation

  8. Specialized beam diagnostic measurements for an ADTT accelerator funnel

    International Nuclear Information System (INIS)

    Gilpatrick, J.D.

    1995-01-01

    Los Alamos National Laboratory has proposed several CW-proton-beam facilities for accelerator-driven transmutation technologies (ADTT) with beam-current densities greater than 5 mA/mm 2 . The primary beam-diagnostics-instrumentation requirement for these facilities is to provide sufficient beam information to understand and minimize beam-loss. To accomplish this task, the beam diagnostics instrumentation must measure beam parameters such as the projected centroids and profiles, total integrated current, and particle loss. Because of the high specific energy loss in materials at beam energies less than 20 MeV, interceptive measurements such as wire scanners or fluors cannot be used to determine beam profiles or centroids. Therefore, noninterceptive techniques must be used for on-line diagnosis of high-intensity CW beam at low energies. The beam funnel area of these proposed accelerator facilities provide a particular interesting beam measurement challenge. In this area of the accelerator, beam measurements must also sense how well the two funnel-input-beams are matched to each other in phase space. This paper will discuss some of the measurement requirements for these proposed accelerator facilities and the various noninterceptive techniques to measure dual-beam funnel operation

  9. Specialized beam diagnostic measurements for an ADTT accelerator funnel

    Energy Technology Data Exchange (ETDEWEB)

    Gilpatrick, J.D.

    1995-10-01

    Los Alamos National Laboratory has proposed several CW-proton-beam facilities for accelerator-driven transmutation technologies (ADTT) with beam-current densities greater than 5 mA/mm{sup 2}. The primary beam-diagnostics-instrumentation requirement for these facilities is to provide sufficient beam information to understand and minimize beam-loss. To accomplish this task, the beam diagnostics instrumentation must measure beam parameters such as the projected centroids and profiles, total integrated current, and particle loss. Because of the high specific energy loss in materials at beam energies less than 20 MeV, interceptive measurements such as wire scanners or fluors cannot be used to determine beam profiles or centroids. Therefore, noninterceptive techniques must be used for on-line diagnosis of high-intensity CW beam at low energies. The beam funnel area of these proposed accelerator facilities provide a particular interesting beam measurement challenge. In this area of the accelerator, beam measurements must also sense how well the two funnel-input-beams are matched to each other in phase space. This paper will discuss some of the measurement requirements for these proposed accelerator facilities and the various noninterceptive techniques to measure dual-beam funnel operation.

  10. Absolute and relative dose measurements with Gafchromic trade mark sign EBT film for high energy electron beams with different doses per pulse

    International Nuclear Information System (INIS)

    Fiandra, Christian; Ragona, Riccardo; Ricardi, Umberto; Anglesio, Silvia; Giglioli, Francesca Romana

    2008-01-01

    The authors have evaluated the accuracy, in absolute and relative dose measurements, of the Gafchromic trade mark sign EBT film in pulsed high-energy electron beams. Typically, the electron beams used in radiotherapy have a dose-per-pulse value of less than 0.1 mGy/pulse. However, very high dose-per-pulse electron beams are employed in certain linear accelerators dedicated to intraoperatory radiation therapy (IORT). In this study, the absorbed dose measurements with Gafchromic trade mark sign EBT in both low (less than 0.3 mGy per pulse) and high (30 and 70 mGy per pulse) dose-per-pulse electron beams were compared with ferrous sulfate chemical Fricke dosimetry (operated by the Italian Primary Standard Dosimetry Laboratory), a method independent of the dose per pulse. A summary of Gafchromic trade mark sign EBT in relative and absolute beam output determination is reported. This study demonstrates the independence of Gafchromic trade mark sign EBT absorption as a function of dose per pulse at different dose levels. A good agreement (within 3%) was found with Fricke dosimeters for plane-base IORT applicators. Comparison with a diode detector is presented for relative dose measurements, showing acceptable agreement both in the steep dose falloff zone and in the homogeneous dose region. This work also provides experimental values for recombination correction factor (K sat ) of a Roos (plane parallel) ionization chamber calculated on the basis of theoretical models for charge recombination.

  11. Energy recovery in high energy neutral beam injectors

    International Nuclear Information System (INIS)

    Laffite, S.

    1991-07-01

    One way to heat the plasma of thermonuclear fusion experiments, is to inject high energy (50 to 100 KeV per nucleon), neutral particles (hydrogen or deuterium). Neutral beam elaboration consists in ion production and acceleration, neutralisation by charge exchange on gas target, disposal of unneutralized ions. But, in the case of positive ion based neutral beam injection, the neutralisation efficiency is limited to 50% at 100 KeV, and decreases rapidly with energy. The energy recovery is a new method for disposing of the unneutralized ions: these are electrostatically decelerated and collected on electrodes which are polarized at low voltage, close to the ion source potential. An energy recovery system was studied and experimented with positive ion beams of 50 and 100 KeV. In the framework of a french-japanese collaboration, we measured a relative power reduction of about 20%, with 100 KeV, 1,5 MW deuterium beams. We have also studied theoretically an energy recovery system for negative ion beams, which will be utilized at high energy (1 MeV). A relative power reduction of 20% can be expected in the best conditions [fr

  12. Pin-photodiode array for the measurement of fan-beam energy and air kerma distributions of X-ray CT scanners.

    Science.gov (United States)

    Haba, Tomonobu; Koyama, Shuji; Aoyama, Takahiko; Kinomura, Yutaka; Ida, Yoshihiro; Kobayashi, Masanao; Kameyama, Hiroshi; Tsutsumi, Yoshinori

    2016-07-01

    Patient dose estimation in X-ray computed tomography (CT) is generally performed by Monte Carlo simulation of photon interactions within anthropomorphic or cylindrical phantoms. An accurate Monte Carlo simulation requires an understanding of the effects of the bow-tie filter equipped in a CT scanner, i.e. the change of X-ray energy and air kerma along the fan-beam arc of the CT scanner. To measure the effective energy and air kerma distributions, we devised a pin-photodiode array utilizing eight channels of X-ray sensors arranged at regular intervals along the fan-beam arc of the CT scanner. Each X-ray sensor consisted of two plate type of pin silicon photodiodes in tandem - front and rear photodiodes - and of a lead collimator, which only allowed X-rays to impinge vertically to the silicon surface of the photodiodes. The effective energy of the X-rays was calculated from the ratio of the output voltages of the photodiodes and the dose was calculated from the output voltage of the front photodiode using the energy and dose calibration curves respectively. The pin-photodiode array allowed the calculation of X-ray effective energies and relative doses, at eight points simultaneously along the fan-beam arc of a CT scanner during a single rotation of the scanner. The fan-beam energy and air kerma distributions of CT scanners can be effectively measured using this pin-photodiode array. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  13. Beam-energy-dependent two-pion interferometry and the freeze-out eccentricity of pions measured in heavy ion collisions at the STAR detector

    Science.gov (United States)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

    2015-07-01

    We present results of analyses of two-pion interferometry in Au +Au collisions at √{sNN}=7.7 , 11.5, 19.6, 27, 39, 62.4, and 200 GeV measured in the STAR detector as part of the BNL Relativistic Heavy Ion Collider Beam Energy Scan program. The extracted correlation lengths (Hanbury-Brown-Twiss radii) are studied as a function of beam energy, azimuthal angle relative to the reaction plane, centrality, and transverse mass (mT) of the particles. The azimuthal analysis allows extraction of the eccentricity of the entire fireball at kinetic freeze-out. The energy dependence of this observable is expected to be sensitive to changes in the equation of state. A new global fit method is studied as an alternate method to directly measure the parameters in the azimuthal analysis. The eccentricity shows a monotonic decrease with beam energy that is qualitatively consistent with the trend from all model predictions and quantitatively consistent with a hadronic transport model.

  14. Merged-beams measurements of electron-capture cross sections for O/sup 5+/+H at electron-volt energies

    International Nuclear Information System (INIS)

    Havener, C.C.; Huq, M.S.; Krause, H.F.; Schulz, P.A.; Phaneuf, R.A.

    1989-01-01

    Absolute total cross-section measurements are presented for electron capture in O/sup 5+/+H(D) collisions over the energy range 0.9--800 eV/amu. These are the first experimental data to be reported using a new multicharged-ion--atom merged-beams apparatus developed at Oak Ridge National Laboratory. The experimental method and the cross-section measurements are described in detail. At energies below 2 eV/amu, the data show a cross-section enhancement which may be attributed to the ion-induced dipole attraction between the reactants. Agreement with recent unpublished quantum-mechanical calculations ranges from fair at the lower energies to excellent at the higher energies

  15. Energy transparency and symmetries in the beam-beam interaction

    Directory of Open Access Journals (Sweden)

    S. Krishnagopal

    2000-02-01

    Full Text Available We have modified the beam-beam simulation code CBI to handle asymmetric beams and used it to look at energy transparency and symmetries in the beam-beam interaction. We find that even a small violation of energy transparency, or of the symmetry between the two beams, changes the character of the collective (coherent motion; in particular, period-n oscillations are no longer seen. We speculate that the one-time observation of these oscillations at LEP, and the more ubiquitous observation of the flip-flop instability in colliders around the world, may be a consequence of breaking the symmetry between the electron and positron beams. We also apply this code to the asymmetric collider PEP-II, and find that for the nominal parameters of PEP-II, in particular, the nominal tune-shift parameter of ξ_{0}=0.03, there are no collective beam-beam issues. Collective quadrupole motion sets in only at ξ_{0}=0.06 and above, consistent with earlier observations for symmetric beams.

  16. Calculation of radiative corrections to virtual compton scattering - absolute measurement of the energy of Jefferson Lab. electron beam (hall A) by a magnetic method: arc project

    International Nuclear Information System (INIS)

    Marchand, D.

    1998-11-01

    This thesis presents the radiative corrections to the virtual compton scattering and the magnetic method adopted in the Hall A at Jefferson Laboratory, to measure the electrons beam energy with an accuracy of 10 4 . The virtual compton scattering experiments allow the access to the generalised polarizabilities of the protons. The extraction of these polarizabilities is obtained by the experimental and theoretical cross sections comparison. That's why the systematic errors and the radiative effects of the experiments have to be controlled very seriously. In this scope, a whole calculation of the internal radiative corrections has been realised in the framework of the quantum electrodynamic. The method of the dimensional regularisation has been used to the treatment of the ultraviolet and infra-red divergences. The absolute measure method of the energy, takes into account the magnetic deviation, made up of eight identical dipoles. The energy is determined from the deviation angle calculation of the beam and the measure of the magnetic field integral along the deviation

  17. A laser-wire beam-energy and beam-profile monitor at the BNL linac

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, R.; Degen, C.; DeSanto, L.; Meng, W.; Michnoff, R.; Minty, M.; Nayak, S.

    2011-03-28

    In 2009 a beam-energy monitor was installed in the high energy beam transport (HEBT) line at the Brookhaven National Lab linac. This device measures the energies of electrons stripped from the 40mA H{sup -} beam by background gas. Electrons are stripped by the 2.0x10{sup -7}torr residual gas at a rate of {approx}1.5x10{sup -8}/cm. Since beam electrons have the same velocities as beam protons, the beam proton energy is deduced by multiplying the electron energy by m{sub p}/m{sub e}=1836. A 183.6MeV H{sup -} beam produces 100keV electrons. In 2010 we installed an optics plates containing a laser and scanning optics to add beam-profile measurement capability via photodetachment. Our 100mJ/pulse, Q-switched laser neutralizes 70% of the beam during its 10ns pulse. This paper describes the upgrades to the detector and gives profile and energy measurements.

  18. Plasma focusing and diagnosis of high energy particle beams

    International Nuclear Information System (INIS)

    Chen, Pisin.

    1990-09-01

    Various novel concepts of focusing and diagnosis of high energy charged particle beams, based on the interaction between the relativistic particle beam and the plasma, are reviewed. This includes overdense thin plasma lenses, and (underdense) adiabatic plasma lens, and two beam size monitor concepts. In addition, we introduce another mechanism for measuring flat beams based on the impulse received by heavy ions in an underdense plasma. Theoretical investigations show promise of focusing and diagnosing beams down to sizes where conventional methods are not possible to provide. 21 refs

  19. Energy and energy width measurement in the FNAL antiproton accumulator

    International Nuclear Information System (INIS)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H 2 gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10 4 in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter η = (P beam /F rev )·(dF rev /dP beam ). These two measurement techniques are described in this report

  20. Energy and energy width measurement in the FNAL antiproton accumulator

    Energy Technology Data Exchange (ETDEWEB)

    Church, M.; Hsueh, S.; Rapidis, P.; Werkema, S.

    1991-10-01

    The Fermilab Antiproton Accumulator has recently been used to produce Charmonium resonances (charm quark, anti-charm quark bound states) in proton-antiproton annihilations using an internal H{sub 2} gas jet target. A measurement of the resonance mass and width may be obtained from a precise knowledge of the antiproton beam energy and energy spread. The beam energy is measured to an accuracy of 1 part in 10{sup 4} in the range 6.3 Gev to 4.1 Gev by measuring the orbit length and revolution frequency of the beam. The beam momentum spread is measured to an accuracy of 10% by measuring the beam frequency spread and the parameter {eta} = (P{sub beam}/F{sub rev}){center_dot}(dF{sub rev}/dP{sub beam}). These two measurement techniques are described in this report.

  1. LHC Beam Instrumentation: Beam Profile Measurements (2/3)

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The LHC is equipped with a full suite of sophisticated beam instrumentation which has been essential for rapid commissioning, the safe increase in total stored beam power and the understanding of machine optics and accelerator physics phenomena. These lectures will introduce these systems and comment on their contributions to the various stages of beam operation. They will include details on: the beam position system and its use for real-time global orbit feedback; the beam loss system and its role in machine protection; total and bunch by bunch intensity measurements; tune measurement and feedback; diagnostics for transverse beam size measurements, abort gap monitoring and longitudinal density measurements. Issues and problems encountered along the way will also be discussed together with the prospect for future upgrades.

  2. Prototyping of beam position monitor for medium energy beam transport section of RAON heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Hyojae, E-mail: lkcom@ibs.re.kr; Jin, Hyunchang; Jang, Ji-Ho; Hong, In-Seok [Rare Isotope Science Project, Institute for Basic Science, Daejeon (Korea, Republic of)

    2016-02-15

    A heavy ion accelerator, RAON is going to be built by Rare Isotope Science Project in Korea. Its target is to accelerate various stable ions such as uranium, proton, and xenon from electron cyclotron resonance ion source and some rare isotopes from isotope separation on-line. The beam shaping, charge selection, and modulation should be applied to the ions from these ion sources because RAON adopts a superconducting linear accelerator structure for beam acceleration. For such treatment, low energy beam transport, radio frequency quadrupole, and medium energy beam transport (MEBT) will be installed in injector part of RAON accelerator. Recently, development of a prototype of stripline beam position monitor (BPM) to measure the position of ion beams in MEBT section is under way. In this presentation, design of stripline, electromagnetic (EM) simulation results, and RF measurement test results obtained from the prototyped BPM will be described.

  3. Turbulence measurements using six lidar beams

    DEFF Research Database (Denmark)

    Sathe, Ameya; Mann, Jakob

    2012-01-01

    components of the Reynolds stress tensor, which arises because, in a VAD scan the lidar beams are combined to obtain different components of the wind field. In this work we demonstrate theoretically, how the contamination by the cross components can be avoided by using the measured variances of the line......The use of wind lidars for measuring wind has increased significantly for wind energy purposes. The mean wind speed measurement using the velocity azimuth display (VAD) technique can now be carried out as reliably as the traditional instruments like the cup and sonic anemometers. Using the VAD...

  4. Fat tissue measurements by dual-energy x-ray absorptiometry: cross-calibration of 3 different fan-beam instruments.

    Science.gov (United States)

    Malouf, Jorge; DiGregorio, Silvana; Del Rio, Luis; Torres, Ferran; Marin, Ana M; Farrerons, Jordi; Herrera, Silvia; Domingo, Pere

    2013-01-01

    Analysis of total tissue composition and, particularly, body fat measurements has become progressively important in the diagnosis and follow-up of patients with different clinical conditions. Dual-energy X-ray absorptiometry (DXA) fan-beam scanners are widely used to measure body composition, but the development of translational equations to be able to compare data of different scanning systems is necessary. The aim of this study was to assess the extent of agreement for regional measurements of body composition among the following 3 fan-beam DXA scanners: (1) Hologic Discovery (Hologic, Inc., Waltham, MA), (2) Lunar iDXA (GE Healthcare, Madison, WI), and (3) Lunar Prodigy Advance (GE Healthcare, Madison, WI). The study population consisted of 91 adult healthy volunteers (40 males and 51 females; mean age 48.5±14.4yr) who underwent DXA evaluation of the lumbar spine, hip, and whole body in each machine on the same day. Agreement among the 3 scanners was evaluated according to the Bland-Altman method and Lin's concordance correlation coefficient. Results showed a better agreement and concordance for the Lunar iDXA scanner than for any of them with the Hologic scanner. Differences were higher for any tissue or region than for the whole tissue mass. Translational equations were developed to ensure comparability of body composition measurements obtained with each of these 3 scanners. Copyright © 2013 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.

  5. Measurement of deuteron beam polarization before and after acceleration

    Directory of Open Access Journals (Sweden)

    A Ramazani Moghaddam Arani

    2017-02-01

    Full Text Available Beam polarization measurement in scattering experiments with a high accuracy and the lowest possible cost is an important issue. In this regard, deuteron beam polarization was measured in the low-energy beam line easily with a relatively low cost procedure and in a very short time by Lamb Shift Polarimeter (LSP. Also, the beam polarization has been measured in high-energy beam line with BINA. In low-energy line, a polarized beam of deuterons delivered by POLIS was decelerated and focused on LSP detection system. Three resonances between 52mT and 63mT show the distribution of different spin states of polarized deuteron beam. In high-energy beam line, polarization can be measured employing BINA via the H(d,dp reaction. The asymmetry ratio, was obtained as a function of azimuthal angle, φ, for several polar scattering angles. Knowing values of the analyzing powers, the ratio has been used to extract the polarization results. The obtained results show that polarization of deuteron beam that is accelerated up to the energy of 130 MeV is almost the same before and after acceleration

  6. Transverse Beam Profile Measurements Using Optical Methods

    CERN Document Server

    Peters, A; Weiss, A; Bank, A

    2001-01-01

    Two different systems are currently under development at GSI's heavy ion facility to measure transverse beam profiles using optical emitters. At the GSI-LINAC for energies up to 15 MeV/u residual gas fluorescence is investigated for pulsed high current beams. The fluorescence of N2 is monitored by an image intensified CCD camera. For all ion species with energies above 50 MeV/u slowly extracted from the synchrotron SIS a classical viewing screen system is used. Three different target materials have been investigated and their behavior concerning efficiency, saturation and timing performance is evaluated. Both systems (will) use CCD cameras with a digital read out using the IEEE 1394 standard.

  7. LHC beam energy in 2012

    International Nuclear Information System (INIS)

    Siemko, A.; Charifouline, Z.; Dahlerup-Petersen, K.; Denz, R.; Ravaioli, E.; Schmidt, R.; Verweij, A.

    2012-01-01

    The interconnections between the LHC main magnets are made of soldered joints (splices) of two superconducting cables stabilized by a copper bus bar. The measurements performed in 2009 in the whole machine, in particular in sector 3-4 during the repair after the 2008 accident, demonstrated that there is a significant fraction of defective copper bus bar joints in the machine. In this paper, the limiting factors for operating the LHC at higher energies with defective 13 kA bus bar joints are briefly reviewed. The experience gained during the 2011 run, including the quench statistics and dedicated quench propagation tests impacting on maximum safe energy are presented. The impact of the by-pass diode contact resistance issue is also addressed. Finally, a proposal for running at the highest possible safe energy compatible with the pre-defined risk level is presented. (authors)

  8. Structuring of silicon with low energy focused ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Nebiker, P.W.; Doebeli, M. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Muehle, R. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1997-09-01

    The defect production in silicon induced by focused ion beam irradiation as a function of energy and projectile mass has been investigated and compared to the measured sputter yield. The aim was to find optimal beam parameters for the structuring of semiconductors with a minimum amount of defects produced per removed atom. (author) 2 figs., 2 refs.

  9. Measurements of bone mineral density in the lumbar spine and proximal femur using lunar prodigy and the new pencil-beam dual-energy X-ray absorptiometry.

    Science.gov (United States)

    Choi, Dongil; Kim, Deog-Yoon; Han, Chung Soo; Kim, Seonwoo; Bok, Hae Sook; Huh, Wooseong; Ko, Jae-Wook; Hong, Sung Hwa

    2010-11-01

    We evaluated the correlation of the absolute bone mineral density (BMD) values of the lumbar spine and standard sites of the proximal femur obtained from a Lunar Prodigy and the newly developed pencil-beam dual-energy X-ray absorptiometry (Dexxum). Between June 2008 and December 2008, 79 Korean volunteers were enrolled. Measurements were obtained on the same day using both densitometers. The absolute BMD values (g/cm(2)) from the two densitometers were evaluated using Pearson's correlation analysis with Bonferroni's correction for the three clinically important sites. In order to evaluate precision, we performed duplicate Dexxum measurements, and calculated the within-subject coefficient of variation (WSCV). The Pearson's correlation coefficient (r) of BMD values for the total proximal femur, femoral neck, and lumbar spine by the two densitometers were 0.926, 0.948, and 0.955 respectively, and the null hypotheses of r = 0.8 were all rejected (p Prodigy.

  10. Beam tuning and stabilization using beam phase measurements at GANIL

    International Nuclear Information System (INIS)

    Chabert, A.; Loyer, F.; Sauret, J.

    1984-06-01

    Owing to the great sensitivity of the beam phase to the various parameters, on line beam phase measurements proved to be a very efficient way of tuning and stabilizing the beam of the multi-accelerator complex. We recall the system which allows to obtain the different kinds of accurate measurements we need and describe the main applications: - tuning process (buncher and SSC's RF phase determination, setting of the required radial beam phase law in the SSC's); - stabilization of the beam by loops, the basic principle of which being to keep constant the beam central phase all along the machine by adjusting RF voltages or magnetic fields. Feedback loops are described and comparative results with and without feedback are given

  11. Improved beam-energy calibration technique for heavy ion accelerators

    International Nuclear Information System (INIS)

    Ferrero, A.M.J.; Garcia, A.; Gil, Salvador

    1989-01-01

    A simple technique for beam energy calibration of heavy-ion accelerators is presented. A thin hydrogenous target was bombarded with 12 C and 19 F, and the energies of the protons knocked out, elastically were measured at several angles using two detectors placed at equal angles on opposite sides of the beam. The use of these two detectors cancels the largest errors due to uncertainties in the angle and position at which the beam hits the target. An application of this energy calibration method to an electrostatic accelerator is described and the calibration constant of the analyzing magnet was obtained with an estimated error of 0.4 (Author) [es

  12. Beam Profile Diagnostics for the Fermilab Medium Energy Electron Cooler

    Science.gov (United States)

    Warner, A.; Kazakevich, G.; Nagaitsev, S.; Tassotto, G.; Gai, W.; Konecny, R.

    2005-10-01

    The Fermilab Recycler ring will employ an electron cooler to store and cool 8.9 GeV antiprotons. The cooler will be based on a Pelletron electrostatic accelerator working in an energy-recovery regime. Several techniques for determining the characteristics of the beam dynamics are being investigated. Beam profiles have been measured as a function of the beam line optics at the energy of 3.5 MeV in the current range of 10/sup -4/-1 A, with a pulse duration of 2 /spl mu/s. The profiles were measured using optical transition radiation produced at the interface of a 250-/spl mu/m aluminum foil and also from YAG crystal luminescence. In addition, beam profiles measured using multiwire detectors were investigated. These three diagnostics will be used together to determine the profile dynamics of the beam. In this paper we report the results so far obtained using these techniques.

  13. Electron beam measurements on the Daresbury SRS

    International Nuclear Information System (INIS)

    Laundy, D.; Cummings, S.

    1992-01-01

    Two experiments which use hard x-ray synchrotron radiation have been carried out to allow us to monitor the electron beam on the Daresbury SRS. The beam spatial and angular vertical position and size was determined over a period of time when the SRS was operating normally. From these measurements, the position and angular stability of the electron beam during the measurement period was assessed and correlation of the beam emittance to the electron current was determined

  14. Beam Loss Calibration Studies for High Energy Proton Accelerators

    CERN Document Server

    Stockner, M

    2007-01-01

    CERN's Large Hadron Collider (LHC) is a proton collider with injection energy of 450 GeV and collision energy of 7 TeV. Superconducting magnets keep the particles circulating in two counter rotating beams, which cross each other at the Interaction Points (IP). Those complex magnets have been designed to contain both beams in one yoke within a cryostat. An unprecedented amount of energy will be stored in the circulating beams and in the magnet system. The LHC outperforms other existing accelerators in its maximum beam energy by a factor of 7 and in its beam intensity by a factor of 23. Even a loss of a small fraction of the beam particles may cause the transition from the superconducting to the normal conducting state of the coil or cause physical damage to machine components. The unique combination of these extreme beam parameters and the highly advanced superconducting technology has the consequence that the LHC needs a more efficient beam cleaning and beam loss measurement system than previous accelerators....

  15. A Symplectic Beam-Beam Interaction with Energy Change

    Energy Technology Data Exchange (ETDEWEB)

    Moshammer, Herbert

    2003-07-14

    The performance of many colliding storage rings is limited by the beam-beam interaction. A particle feels a nonlinear force produced by the encountering bunch at the collision. This beam-beam force acts mainly in the transverse directions so that the longitudinal effects have scarcely been studied, except for the cases of a collision with a crossing angle. Recently, however, high luminosity machines are being considered where the beams are focused extensively at the interaction point (IP) so that the beam sizes can vary significantly within the bunch length. Krishnagopal and Siemann have shown that they should not neglect the bunch length effect in this case. The transverse kick depends on the longitudinal position as well as on the transverse position. If they include this effect, however, from the action-reaction principle, they should expect, at the same time, an energy change which depends on the transverse coordinates. Such an effect is reasonably understood from the fact that the beam-beam force is partly due to the electric field, which can change the energy. The action-reaction principle comes from the symplecticity of the reaction: the electromagnetic influence on a particle is described by a Hamiltonian. The symplecticity is one of the most fundamental requirements when studying the beam dynamics. A nonsymplectic approximation can easily lead to unphysical results. In this paper, they propose a simple, approximately but symplectic mapping for the beam-beam interaction which includes the energy change as well as the bunch-length effect. In the next section, they propose the mapping in a Hamiltonian form, which directly assures its symplecticity. Then in section 3, they study the nature of the mapping by interpreting its consequences. The mapping itself is quite general and can be applied to any distribution function. They show in Section 4 how it appears when the distribution function is a Gaussian in transverse directions. The mapping is applied to the

  16. Disruption effects on the beam size measurement

    International Nuclear Information System (INIS)

    Raimondi, P.; Decker, F.J.; Chen, P.

    1995-01-01

    At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D y is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10 10 particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 μm horizontally and 0.55 μm vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H D of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit

  17. Funneling of low energy ion beams

    International Nuclear Information System (INIS)

    Barth, W.; Schempp, A.

    1992-01-01

    Funneling two or more beams together is a way of increasing the brightness of ion beams by filling all rf-buckets of an rf-accelerator. Thus higher current transport capability results at higher energies and operating frequencies. It can be used to reduce the cost and complexity of accelerators designed to produce intense beams with high brightness. Results of numerical simulations and funneling experiments are reported, where a setup with a 50-keV proton beam and an rf deflector is investigated to study emittance growth effects in funneling lines. (R.P.) 13 refs.; 9 figs.; 1 tab

  18. A compact, versatile low-energy electron beam ion source

    Energy Technology Data Exchange (ETDEWEB)

    Zschornack, G., E-mail: g.zschornack@hzdr.de [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany); König, J.; Schmidt, M.; Thorn, A. [DREEBIT GmbH, 01109 Dresden (Germany)

    2014-02-15

    A new compact Electron Beam Ion Source, the Dresden EBIT-LE, is introduced as an ion source working at low electron beam energies. The EBIT-LE operates at an electron energy ranging from 100 eV to some keV and can easily be modified to an EBIT also working at higher electron beam energies of up to 15 keV. We show that, depending on the electron beam energy, electron beam currents from a few mA in the low-energy regime up to about 40 mA in the high-energy regime are possible. Technical solutions as well as first experimental results of the EBIT-LE are presented. In ion extraction experiments, a stable production of low and intermediate charged ions at electron beam energies below 2 keV is demonstrated. Furthermore, X-ray spectroscopy measurements confirm the possibility of using the machine as a source of X-rays from ions excited at low electron energies.

  19. Beam Profile Measurement in MTA Beam Line for High Pressure RF Cavity Beam Test

    International Nuclear Information System (INIS)

    Jana, M.R.; Bross, A.; Chung, M.; Greer, S.; Johnstone, C.; Kobilarcik, T.; Koizumi, G.; Leonova, M.; Moretti, A.; Popovic, M.; Schwartz, T.

    2012-01-01

    Recent High Pressure RF (HPRF) cavity experiment at MuCool Test Area (MTA) has used 400 MeV Linac proton beam to study the beam loading effect. When the energetic proton beam passes through the cavity, it ionizes the inside gas and produces the electrons. These electrons consume RF power inside the cavity. Number of electrons produced per cm inside the cavity (at 950 psi Hydrogen gas) per incident proton is ∼ 1200. The measurement of beam position and profile are necessary. MTA is flammable gas (Hydrogen) hazard zone so we have developed a passive beam diagnostic instrument using Chromox-6 scintillation screen and CCD camera. This paper presents quantitative information about beam position and beam profile. Neutral density filter was used to avoid saturation of CCD camera. Image data is filtered and fitted with Gaussian function to compute the beam size. The beam profile obtained from scintillation screen shall be compared with multi-wire beam profile.

  20. Measurements of bone mineral density in the lumbar spine and proximal femur using lunar prodigy and the new pencil-beam dual-energy X-ray absorptiometry

    International Nuclear Information System (INIS)

    Choi, Dongil; Kim, Deog-Yoon; Han, Chung Soo; Kim, Seonwoo; Bok, Hae Sook; Huh, Wooseong; Ko, Jae-Wook; Hong, Sung Hwa

    2010-01-01

    We evaluated the correlation of the absolute bone mineral density (BMD) values of the lumbar spine and standard sites of the proximal femur obtained from a Lunar Prodigy and the newly developed pencil-beam dual-energy X-ray absorptiometry (Dexxum). Between June 2008 and December 2008, 79 Korean volunteers were enrolled. Measurements were obtained on the same day using both densitometers. The absolute BMD values (g/cm 2 ) from the two densitometers were evaluated using Pearson's correlation analysis with Bonferroni's correction for the three clinically important sites. In order to evaluate precision, we performed duplicate Dexxum measurements, and calculated the within-subject coefficient of variation (WSCV). The Pearson's correlation coefficient (r) of BMD values for the total proximal femur, femoral neck, and lumbar spine by the two densitometers were 0.926, 0.948, and 0.955 respectively, and the null hypotheses of r = 0.8 were all rejected (p < 0.001 by one-sided Z-test with Fisher's z-transformation for each site). The T-scores (r ≥ 0.842) and Z-scores (r ≥ 0.709) also showed strong positive correlations. The duplicate BMD values of Dexxum showed a high level of precision (WSCV ≤ 4.27%). Dexxum measurements of BMD, T-scores, and Z-scores showed a strong linear correlation with those measured on Lunar Prodigy. (orig.)

  1. Measurements of bone mineral density in the lumbar spine and proximal femur using lunar prodigy and the new pencil-beam dual-energy X-ray absorptiometry

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Dongil [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center, Seoul (Korea, Republic of); Kim, Deog-Yoon [Kyung Hee University, Department of Nuclear Medicine, College of Medicine, Seoul (Korea, Republic of); Han, Chung Soo [Kyung Hee University, Department of Orthopedic Surgery, College of Medicine, Seoul (Korea, Republic of); Kim, Seonwoo [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Samsung Medical Center, Biostatistics Unit, Samsung Biomedical Research Institute, Seoul (Korea, Republic of); Bok, Hae Sook [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Huh, Wooseong [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Division of Nephrology, Samsung Medical Center, Seoul (Korea, Republic of); Ko, Jae-Wook [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Division of Clinical Pharmacology, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Hong, Sung Hwa [Sungkyunkwan University School of Medicine, Clinical Trial Center, Clinical Research Institute, Samsung Medical Center, Seoul (Korea, Republic of); Sungkyunkwan University School of Medicine, Department of Otorhinolaryngology-Head and Neck Surgery, Samsung Medical Center, Seoul (Korea, Republic of)

    2010-11-15

    We evaluated the correlation of the absolute bone mineral density (BMD) values of the lumbar spine and standard sites of the proximal femur obtained from a Lunar Prodigy and the newly developed pencil-beam dual-energy X-ray absorptiometry (Dexxum). Between June 2008 and December 2008, 79 Korean volunteers were enrolled. Measurements were obtained on the same day using both densitometers. The absolute BMD values (g/cm{sup 2}) from the two densitometers were evaluated using Pearson's correlation analysis with Bonferroni's correction for the three clinically important sites. In order to evaluate precision, we performed duplicate Dexxum measurements, and calculated the within-subject coefficient of variation (WSCV). The Pearson's correlation coefficient (r) of BMD values for the total proximal femur, femoral neck, and lumbar spine by the two densitometers were 0.926, 0.948, and 0.955 respectively, and the null hypotheses of r = 0.8 were all rejected (p < 0.001 by one-sided Z-test with Fisher's z-transformation for each site). The T-scores (r {>=} 0.842) and Z-scores (r {>=} 0.709) also showed strong positive correlations. The duplicate BMD values of Dexxum showed a high level of precision (WSCV {<=} 4.27%). Dexxum measurements of BMD, T-scores, and Z-scores showed a strong linear correlation with those measured on Lunar Prodigy. (orig.)

  2. Prospects for measuring G{sub M{sub N}} in CLAS with higher CEBAF beam energies

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, W. [CEBAF, Newport News, VA (United States)

    1994-04-01

    The possibility exists for extending a planned measurement of the neutron magnetic form factor to higher values of momentum transfer. The theoretical interest and the experimental method are described. Problems associated with higher Q{sup 2} measurements are discussed. It is concluded that measurements of moderate precision may be possible up to a Q{sup 2} of 8-9.5 GeV{sup 2}, more than doubling the range of the data currently available.

  3. Moving core beam energy absorber and converter

    Science.gov (United States)

    Degtiarenko, Pavel V.

    2012-12-18

    A method and apparatus for the prevention of overheating of laser or particle beam impact zones through the use of a moving-in-the-coolant-flow arrangement for the energy absorbing core of the device. Moving of the core spreads the energy deposition in it in 1, 2, or 3 dimensions, thus increasing the effective cooling area of the device.

  4. Microstructure cantilever beam for current measurement

    Directory of Open Access Journals (Sweden)

    M.T.E. Khan

    2010-01-01

    Full Text Available Most microelectromechanical systems (MEMS sensors are based on the microcantilever technology, which uses a broad range of design materials and structures. The benefit ofMEMStechnology is in developing devices with a lower cost, lower power consumption, higher performance and greater integration. A free-end cantilever beam with a magnetic material mass has been designed using MEMS software tools. The magnetic material was used to improve the sensitivity of the cantilever beam to an externally-applied magnetic field. The cantilever was designed to form a capacitance transducer, which consisted of variable capacitance where electrical and mechanical energies were exchanged. The aim of this paper was to analyse the system design of the microcantilever when subjected to a magnetic field produced by a current-carrying conductor. When the signal, a sinusoidal current with a constant frequency, was applied, the cantilever beam exhibited a vibration motion along the vertical axis when placed closer to the line current. This motion created corresponding capacitance changes and generated a voltage output proportional to the capacitive change in the signal-processing circuitry attached to the microcantilever. The equivalent massspring system theory was used to describe and analyse the effect of the natural frequency of the system vibrations and motion due to the applied magnetic field, in a single-degree of freedom. The main application of this microcantilever is in current measurements to develop a non-contact current sensor mote.

  5. Measurement of activity produced by low energy proton beam in metals using off-line PET imaging

    OpenAIRE

    Corzo, P. M. G.; Cal González, Jacobo; Picado, E.; España, Samuel; Herraiz, J. L.; Herranz, Elena; Vicente, Esther; Udías, José Manuel; Vaquero López, Juan José; Muñoz Martín, A.; Fraile, L. M.

    2011-01-01

    Proceeding of: 2011 Nuclear Science Symposium and Medical Imaging Conference, Valencia, España, 23-29 October, 2011 In this work, we investigate PET imaging with 68Ga and 66Ga after proton irradiation on a natural zinc foil. The nuclides 68Ga and 66Ga are ideally suited for off line PET monitoring of proton radiotherapy due to their beta decay halflives of 67.71(9) minutes and 9.49(3) hours, respectively, and suitable fl end point energy. The purpose of this work is to explore the feasibil...

  6. Beam based measurement of beam position monitor electrode gains

    OpenAIRE

    D. L. Rubin; M. Billing; R. Meller; M. Palmer; M. Rendina; N. Rider; D. Sagan; J. Shanks; C. Strohman

    2010-01-01

    Low emittance tuning at the Cornell Electron Storage Ring (CESR) test accelerator depends on precision measurement of vertical dispersion and transverse coupling. The CESR beam position monitors (BPMs) consist of four button electrodes, instrumented with electronics that allow acquisition of turn-by-turn data. The response to the beam will vary among the four electrodes due to differences in electronic gain and/or misalignment. This variation in the response of the BPM electrodes will couple ...

  7. Forward energy measurement with CMS

    CERN Document Server

    Kheyn, Lev

    2016-01-01

    Energy flow is measured in the forward region of CMS at pseudorapidities up to 6.6 in pp interactions at 13 TeV with forward (HF) and very forward (CASTOR) calorimeters. The results are compared to model predictions. The CMS results at different center-of-mass energies are intercompared using pseudorapidity variable shifted by beam rapidity, thus studying applicability of hypothesis of limiting fragmentation.

  8. Spectra of linear energy transfer and other dosimetry characteristics as measured in C290 MeV/n MONO and SOBP ion beams at HIMAC-BIO (NIRS, Japan) with different detectors.

    Science.gov (United States)

    Spurný, F; Pachnerová Brabcová, K; Ploc, O; Ambrožová, I; Mrázová, Z

    2011-02-01

    Active mobile dosimetry unit (Liulin), passive plastic nuclear track detectors (PNTD) and thermoluminescent detectors (TLD) were exposed in a C290 MeV/n beam at HIMAC-BIO (NIRS, Japan). Two different types of beam configuration were used--monoenergetic beam (MONO) and spread-out Bragg peak (SOBP); the detectors were placed at several depths from the entrance up to the depths behind the Bragg peak. Relative response of TLDs in beams has been studied as a function of the depth, and it was re-proved that it can depend on the linear energy transfer (LET). Liulin measures energy deposition in Si; the spectra of energy deposited in Si can be transformed to the spectra of lineal energy or LET. PNTDs are able to determine the LET of registered particles directly. The limitation of both methods is in the range in which they can determine the LET-Liulin is able to measure perpendicularly incident charged particles up to ∼35 keV/µm (in water), PNTD can measure from ∼7 to 400 keV/µm, independently of the registration angle. The results from both methods are compared and combined for both beams' configuration, and a good agreement is observed.

  9. MEASUREMENTS OF INTRA-BEAM SCATTERING GROWTH TIMES WITH GOLD BEAM BELOW TRANSITION IN RHIC

    International Nuclear Information System (INIS)

    FISCHER, W.; BAI, M.; BLASKIEWICZ, M.; BRENNAN, J.M.; CAMERON, P.; CONNOLLY, R.; LEHRACH, A.; PARZEN, G.; TEPIKIAN, S.; ZENO, K.; VAN ZEIJTS, J.

    2001-01-01

    While RHIC is filled with beam, bunches are stored for up to several minutes at the injection energy before acceleration starts. In gold operation, the RHIC injection energy is below transition. A bunch length increase, and correspondingly an increase in the longitudinal emittance, can lead to particle loss during transition crossing and rebucketing into the storage buckets. The longitudinal growth of gold beams in RHIC at injection is dominated by intra-beam scattering. Measurements of longitudinal growth times are presented and compared with computations

  10. Super High Energy Colliding Beam Accelerators

    International Nuclear Information System (INIS)

    Abdelaziz, M.E.

    2009-01-01

    This lecture presents a review of cyclic accelerators and their energy limitations. A description is given of the phase stability principle and evolution of the synchrotron, an accelerator without energy limitation. Then the concept of colliding beams emerged to yield doubling of the beam energy as in the Tevatron 2 trillion electron volts (TeV) proton collider at Fermilab and the Large Hadron Collider (LHC) which is now planned as a 14-TeV machine in the 27 kilometer tunnel of the Large Electron Positron (LEP) collider at CERN. Then presentation is given of the Superconducting Supercollider (SSC), a giant accelerator complex with energy 40-TeV in a tunnel 87 kilometers in circumference under the country surrounding Waxahachie in Texas, U.S.A. These superhigh energy accelerators are intended to smash protons against protons at energy sufficient to reveal the nature of matter and to consolidate the prevailing general theory of elementary particle.

  11. A graphite calorimeter for absolute measurements of absorbed dose to water: application in medium-energy x-ray filtered beams.

    Science.gov (United States)

    Pinto, M; Pimpinella, M; Quini, M; D'Arienzo, M; Astefanoaei, I; Loreti, S; Guerra, A S

    2016-02-21

    The Italian National Institute of Ionizing Radiation Metrology (ENEA-INMRI) has designed and built a graphite calorimeter that, in a water phantom, has allowed the determination of the absorbed dose to water in medium-energy x-rays with generating voltages from 180 to 250 kV. The new standard is a miniaturized three-bodies calorimeter, with a disc-shaped core of 21 mm diameter and 2 mm thickness weighing 1.134 g, sealed in a PMMA waterproof envelope with air-evacuated gaps. The measured absorbed dose to graphite is converted into absorbed dose to water by means of an energy-dependent conversion factor obtained from Monte Carlo simulations. Heat-transfer correction factors were determined by FEM calculations. At a source-to-detector distance of 100 cm, a depth in water of 2 g cm(-2), and at a dose rate of about 0.15 Gy min(-1), results of calorimetric measurements of absorbed dose to water, D(w), were compared to experimental determinations, D wK, obtained via an ionization chamber calibrated in terms of air kerma, according to established dosimetry protocols. The combined standard uncertainty of D(w) and D(wK) were estimated as 1.9% and 1.7%, respectively. The two absorbed dose to water determinations were in agreement within 1%, well below the stated measurement uncertainties. Advancements are in progress to extend the measurement capability of the new in-water-phantom graphite calorimeter to other filtered medium-energy x-ray qualities and to reduce the D(w) uncertainty to around 1%. The new calorimeter represents the first implementation of in-water-phantom graphite calorimetry in the kilovoltage range and, allowing independent determinations of D(w), it will contribute to establish a robust system of absorbed dose to water primary standards for medium-energy x-ray beams.

  12. Measurement of Beam Lifetime and Applications for SPEAR3

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Xiaobiao; Corbett, Jeff; /SLAC

    2011-04-05

    Beam lifetime studies for the SPEAR3 storage ring are presented. The three lifetime components are separated with lifetime measurements under various combinations of beam currents and fill patterns and vertical scraper scans. Touschek lifetime is studied with rf voltage scans and with the horizontal or vertical scrapers inserted. The measurements are explained with calculations based on the calibrated lattice model. Quantum lifetime measurements are performed with reduced longitudinal and horizontal apertures, respectively, from which we deduce the radiation energy loss down to a few keV per revolution and the horizontal beam size.

  13. Beam based measurement of beam position monitor electrode gains

    Directory of Open Access Journals (Sweden)

    D. L. Rubin

    2010-09-01

    Full Text Available Low emittance tuning at the Cornell Electron Storage Ring (CESR test accelerator depends on precision measurement of vertical dispersion and transverse coupling. The CESR beam position monitors (BPMs consist of four button electrodes, instrumented with electronics that allow acquisition of turn-by-turn data. The response to the beam will vary among the four electrodes due to differences in electronic gain and/or misalignment. This variation in the response of the BPM electrodes will couple real horizontal offset to apparent vertical position, and introduce spurious measurements of coupling and vertical dispersion. To alleviate this systematic effect, a beam based technique to measure the relative response of the four electrodes has been developed. With typical CESR parameters, simulations show that turn-by-turn BPM data can be used to determine electrode gains to within ∼0.1%.

  14. First Beam Transfer Function measurements at LHC

    CERN Document Server

    Tambasco, Claudia; Fuchsberger, Kajetan; Lefevre, Thibaut; Pieloni, Tatiana; Barranco Garcia, Javier; Boccardi, Andrea; Gasior, Marek; Levens, Tom; Albert, Markus; CERN. Geneva. ATS Department

    2015-01-01

    For the first time in the LHC, Beam Transfer Function (BTF) measurements have been performed. Different machine configurations have been tested to determine the safety of the BTF measurement system that results to be completely transparent on single beam. To evaluate the spread given by different Landau octupole currents, an octupole current scan was performed. The data analysis is still ongoing. The BTF measurements have been tested also for beams in collision, the first attempt at 450 GeV resulted in the excitation of the beam-beam coherent -mode, while a second attempt at 6.5 GeV did not show any signs of instability. This is still under investigation and further tests are needed also with trains of bunches.

  15. In situ measurement of laser beam quality

    Science.gov (United States)

    Hashemi, Somayeh Sadat; Ghavami Sabouri, Saeed; Khorsandi, Alireza

    2017-09-01

    An innovative optical method is introduced for the beam quality measurement of any arbitrary transverse mode based on the reconstruction of the mode from a few-frame image of the beam cross-section. This is performed by the decomposition of a mode to its basic Hermite-Gaussian modal coefficients. The performance of the proposed method is examined through M 2-factor measurement of the beam of a Nd:YAG laser which was forced to oscillate in a certain mode using a crossed rectangular intracavity aperture. Obtained results have shown that this method can be alternatively replaced for the hologram- and ISO-based techniques recently exploiting for beam quality measurement regardless of the mode type and the position of utilized CCD camera along the beam direction.

  16. Phase measurement and control of bunched beams

    International Nuclear Information System (INIS)

    Lewis, R.N.

    1978-01-01

    An ion bean buncher was developed at ANL for bunching all ion species through a tandem accelerator. Transit time variations through the tandem, caused by ripple and fluctuations in the injection and lens power supplies and terminal voltage, and to varying voltage distributions in the accelerating tube, cause a beam-phase variation at the output of the tandem. A beam-phase measurement and control system was designed and installed in conjunction with the ion beam buncher to control beam phase at the tandem output. That system is described

  17. A device for measuring electron beam characteristics

    Directory of Open Access Journals (Sweden)

    M. Andreev

    2017-01-01

    Full Text Available This paper presents a device intended for diagnostics of electron beams and the results obtained with this device. The device comprises a rotating double probe operating in conjunction with an automated probe signal collection and processing system. This provides for measuring and estimating the electron beam characteristics such as radius, current density, power density, convergence angle, and brightness.

  18. Space Charge Compensation in the Linac4 Low Energy Beam Transport Line with Negative Hydrogen Ions

    CERN Document Server

    Valerio-Lizarraga, C; Leon-Monzon, I; Lettry, J; Midttun, O; Scrivens, R

    2014-01-01

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Tranport (LEBT) using the package IBSimu1, which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H- beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  19. First Beam Measurements with the LHC Synchrotron Light Monitors

    CERN Document Server

    Bravin, E; Fisher, AS; Guerrero, A; Jeff, A; Lefevre, T; Goldblatt, A; Roncarolo, F

    2010-01-01

    The continuous monitoring of the transverse sizes of the beams in the Large Hadron Collider (LHC) relies on the use of synchrotron radiation and intensified video cameras. Depending on the beam energy, different synchrotron light sources must be used. A dedicated superconducting undulator has been built for low beam energies (450 GeV to 1.5 TeV), while edge and centre radiation from a beam-separation dipole magnet are used respectively for intermediate and high energies (up to 7 TeV). The emitted visible photons are collected using a retractable mirror, which sends the light into an optical system adapted for acquisition using intensified CCD cameras. This paper presents the design of the imaging system, and compares the expected light intensity with measurements and the calculated spatial resolution with a cross calibration performed with the wire scanners. Upgrades and future plans are also discussed.

  20. Disruption effects on the beam size measurement

    Energy Technology Data Exchange (ETDEWEB)

    Raimondi, P.; Decker, F.J.; Chen, P.

    1995-06-01

    At the SLC Final Focus with higher currents and smaller beam sizes, the disruption parameter D{sub y} is close to one and so the pinch effect should produce a luminosity enhancement. Since a flat beam-beam function is fit to deflection scan data to measure the beam size, disruption can affect the measurement. Here the authors discuss the quantitative effects of disruption for typical SLC beam parameters. With 3.5 10{sup 10} particles per pulse, bunch length of 0.8 mm and beam sizes of 2.1 {mu}m horizontally and 0.55 {mu}m vertically, the measured vertical size can be as much as 25% bigger than the real one. Furthermore during the collision the spot size actually decrease, producing an enhancement factor H{sub D} of about 1.25. This would yield to a true luminosity which is 1.6 times that which is estimated from the beam-beam deflection fit.

  1. Beamed-Energy Propulsion (BEP) Study

    Science.gov (United States)

    George, Patrick; Beach, Raymond

    2012-01-01

    The scope of this study was to (1) review and analyze the state-of-art in beamed-energy propulsion (BEP) by identifying potential game-changing applications, (2) formulate a roadmap of technology development, and (3) identify key near-term technology demonstrations to rapidly advance elements of BEP technology to Technology Readiness Level (TRL) 6. The two major areas of interest were launching payloads and space propulsion. More generally, the study was requested and structured to address basic mission feasibility. The attraction of beamed-energy propulsion (BEP) is the potential for high specific impulse while removing the power-generation mass. The rapid advancements in high-energy beamed-power systems and optics over the past 20 years warranted a fresh look at the technology. For launching payloads, the study concluded that using BEP to propel vehicles into space is technically feasible if a commitment to develop new technologies and large investments can be made over long periods of time. From a commercial competitive standpoint, if an advantage of beamed energy for Earth-to-orbit (ETO) is to be found, it will rest with smaller, frequently launched payloads. For space propulsion, the study concluded that using beamed energy to propel vehicles from low Earth orbit to geosynchronous Earth orbit (LEO-GEO) and into deep space is definitely feasible and showed distinct advantages and greater potential over current propulsion technologies. However, this conclusion also assumes that upfront infrastructure investments and commitments to critical technologies will be made over long periods of time. The chief issue, similar to that for payloads, is high infrastructure costs.

  2. Funneling of low energy ion beams

    International Nuclear Information System (INIS)

    Barth, W.; Schempp, A.

    1992-01-01

    Funneling is a way of increasing the brightness of ion beams by filling all buckets of a rf-accelerator and using the higher current transport capability at higher energies. Funnel systems have been proposed, e.g. for HIIF type drivers and spallation neutron sources. Results of numerical simulations and funneling experiments at Frankfurt are reported, where a setup with a 50 keV proton beam and a rf deflector is investigated to study especially emittance growth effects in funneling lines. (Author) 9 figs., tab., 13 refs

  3. Development of diagnostic beams for alpha particle measurement on ITER

    Energy Technology Data Exchange (ETDEWEB)

    Sasao, M.; Taniike, A.; Nomura, I.; Wada, M.; Yamaoka, H.; Sato, M.

    1995-08-01

    The feasibility of alpha particle measurement using a high energy diagnostic beam in combination with a neutral particle analyzer is examined for a burning plasma on ITER. In order to measure them in the energy range of 0.5 - 3.5 MeV, the required beam energy is around 1 MeV for a {sup 3}He{sup 0} beam and 3 MeV for a {sup 6}Li{sup 0} beam with the beam current density of around 1 mA/cm{sup 2} for both cases. Among the various methods to produce such a high energy neutral beam, the acceleration of negative ions is most favorable. Recent results of relatively small-scale experiments on these negative ion sources show that the required current density is now realistic. Some technical problems how to scale-up the ion sources to be used on an ITER-size experiment are also studied on these experiments. (author).

  4. Atomic physics measurements in an electron beam ion trap

    Science.gov (United States)

    Marrs, R. E.; Beiersdorfer, P.; Bennett, C.; Chen, M. H.; Cowan, T.; Dietrich, D.; Henderson, J. R.; Knapp, D. A.; Osterheld, S.; Schneider, M. B.; Scofield, J. H.; Levine, M. A.

    1989-06-01

    An electron Beam Ion Trap at Lawrence Livermore National Laboratory is being used to produce and trap very-highly-charged ions (q≥70+) for x-ray spectroscopy measurements. Recent measurements of transition energies and electron excitation cross sections for x-ray line emission are summarized.

  5. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: -> Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. -> Deconvolution of the luminosity spectrum distortion due to the ISR emission. -> Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  6. Correction of beam-beam effects in luminosity measurement in the forward region at CLIC

    CERN Document Server

    Lukic, Strahinja

    2013-01-01

    Procedures for correcting the beam-beam effects in luminosity measurement at CLIC at 3 TeV CM energy are described and tested using Monte Carlo simulations: - Correction of the angular counting loss due to the combined Beamstrahlung and initial-state radiation (ISR) effects, based on the reconstructed velocity of the collision frame of the Bhabha scattering. - Deconvolution of the luminosity spectrum distortion due to the ISR emission. - Correction of the counting bias due to the finite calorimeter energy resolution. All procedures were tested by simulation. Bhabha events were generated using BHLUMI, and used in Guinea-PIG to simulate the outgoing momenta of Bhabha particles in the bunch collisions at CLIC. Residual uncertainties after correction are listed in a table in the conclusions. The beam-beam related systematic counting uncertainty in the luminosity peak can be reduced to the order of permille.

  7. Measuring emittance using beam position monitors

    International Nuclear Information System (INIS)

    Russell, S.; Carlsten, B.

    1993-01-01

    The Los Alamos Advanced Free Electron Laser uses a high charge (greater than InC), low emittance (normalized rams emittance less than 5π mm mrad) photoinjector driven accelerator. The high brightness achieved is due, in large part, to the rapid acceleration of the electrons to relativistic velocities. As a result, the beam does not have time to thermalize its distribution and its universe profile is, in general, non-Gaussian. This, coupled with the very high brightness, makes it difficult to measure the transverse emittance. Techniques used must be able to withstand the rigors of very intense electron beams, and not be reliant on Gaussian assumptions. Beam position monitors are ideal for this. They are not susceptible to beam damage, and it has been shown previously that they can be used to measure the transverse emittance of a beam with a Gaussian profile. However, this Gaussian restriction is not necessary and, in fact, a transverse emittance measurement using beam position monitors is independent of the beam's distribution

  8. Test Beam Measurements on Picosec Gaseous Detector.

    CERN Document Server

    Sohl, Lukas

    2017-01-01

    In the Picosec project micro pattern gaseous detectors with a time resolution of some ten picoseconds are developed. The detectors are based on Micromegas detectors. With a cherenkov window and a photocathode the time jitter from different position of the primary ionization clusters can be substituted. This reports describes the beam setup and measurements of different Picosec prototypes. A time resolution of under 30 ps has been measured during the test beam. This report gives an overview of my work as a Summer Student. I set up and operated a triple-GEM tracker and a trigger system for the beam. During the beam I measured different prototypes of Picosec detectors and analysed the data.

  9. Alternative techniques for beam halo measurements

    CERN Document Server

    Welsch, CP; Burel, B; Lefèvre, T; Chapman, T; Pilon, MJ

    2006-01-01

    In future high intensity, high energy accelerators it must be ensured that particle losses are minimized, as activation of the vacuum chambers or other components makes maintenance and upgrade work time consuming and costly. It is imperative to have a clear understanding of the mechanisms that can lead to halo formation and to have the possibility to test available theoretical models with an adequate experimental setup. Measurements based on optical transition radiation (OTR) are a well-established technique for measurements of the transverse beam profile. However, in order to be suitable for halo measurements as well, the dynamic range of the final image acquisition system needs to be high, being able to cover at least five orders of magnitude in intensity changes. Here, the performance of a standard acquisition system as it is used in the CLIC test facility (CTF3) is compared to a step-by-step measurement with a small movable photo multiplier tube and an innovative camera system based on charge injection de...

  10. Employing Beam-Gas Interaction Vertices for Transverse Profile Measurements

    CERN Document Server

    Rihl, Mariana; Baglin, Vincent; Barschel, Colin; Bay, Aurelio; Blanc, Frederic; Bravin, Enrico; Bregliozzi, Giuseppe; Chritin, Nicolas; Dehning, Bernd; Ferro-Luzzi, Massimiliano; Gaspar, Clara; Gianì, Sebastiana; Giovannozzi, Massimo; Greim, Roman; Haefeli, Guido; Hopchev, Plamen; Jacobsson, Richard; Jensen, Lars; Jones, Owain Rhodri; Jurado, Nicolas; Kain, Verena; Karpinski, Waclaw; Kirn, Thomas; Kuhn, Maria; Luthi, Berengere; Magagnin, Paolo; Matev, Rosen; Nakada, Tatsuya; Neufeld, Niko; Panman, Jaap; Rakotomiaramanana, Barinjaka; Salustino Guimaraes, Valdir; Salvant, Benoit; Schael, Stefan; Schneider, Olivier; Schwering, Georg; Tobin, Mark; Veness, Raymond; Veyrat, Quentin; Vlachos, Sotiris; Wlochal, Michael; Xu, Zhirui; von Dratzig, Arndt

    2016-01-01

    Interactions of high-energy beam particles with residual gas offer a unique opportunity to measure the beam profile in a non-intrusive fashion. Such a method was successfully pioneered* at the LHCb experiment using a silicon microstrip vertex detector. During the recent Large Hadron Collider shutdown at CERN, a demonstrator Beam-Gas Vertexing system based on eight scintillating-fibre modules was designed**, constructed and installed on Ring 2 to be operated as a pure beam diagnostics device. The detector signals are read out and collected with LHCb-type front-end electronics and a DAQ system consisting of a CPU farm. Tracks and vertices will be reconstructed to obtain a beam profile in real time. Here, first commissioning results are reported. The advantages and potential for future applications of this technique are discussed.

  11. A system for online beam emittance measurements and proton beam characterization

    Science.gov (United States)

    Nesteruk, K. P.; Auger, M.; Braccini, S.; Carzaniga, T. S.; Ereditato, A.; Scampoli, P.

    2018-01-01

    A system for online measurement of the transverse beam emittance was developed. It is named 4PrOBεaM (4-Profiler Online Beam Emittance Measurement) and was conceived to measure the emittance in a fast and efficient way using the multiple beam profiler method. The core of the system is constituted by four consecutive UniBEaM profilers, which are based on silica fibers passing across the beam. The 4PrOBεaM system was deployed for characterization studies of the 18 MeV proton beam produced by the IBA Cyclone 18 MeV cyclotron at Bern University Hospital (Inselspital). The machine serves daily radioisotope production and multi-disciplinary research, which is carried out with a specifically conceived Beam Transport Line (BTL). The transverse RMS beam emittance of the cyclotron was measured as a function of several machine parameters, such as the magnetic field, RF peak voltage, and azimuthal angle of the stripper. The beam emittance was also measured using the method based on the quadrupole strength variation. The results obtained with both techniques were compared and a good agreement was found. In order to characterize the longitudinal dynamics, the proton energy distribution was measured. For this purpose, a method was developed based on aluminum absorbers of different thicknesses, a UniBEaM detector, and a Faraday cup. The results were an input for a simulation of the BTL developed in the MAD-X software. This tool allows machine parameters to be tuned online and the beam characteristics to be optimized for specific applications.

  12. Beam structure studies of low-energy ion beams

    Science.gov (United States)

    Saadatmand, K.; Schneider, J. D.; Geisik, C.; Stevens, R. R.

    1991-05-01

    The ion beam structure at various axial positions along the beam-transport line has been monitored and studied utilizing a fluor screen and a video camera. The fluor material is aluminum oxide that is plasma-jet sprayed onto the surface of an aluminum or a water-cooled copper substrate. The visual representation of the beam structure is digitized and enhanced through use of false-color coding and displayed on a TV monitor for the on-line viewing by the experimentalist. Digitized video signals are stored for further off-line processing and extracting more information about the beam, such as beam profiles. This inexpensive and effective diagnostic enables the experimentalist to observe the real-time beam response (such as evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position) to parameter changes.

  13. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-08-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  14. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    Energy Technology Data Exchange (ETDEWEB)

    Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2010-03-16

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

  15. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-01-01

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state

  16. Precision luminosity measurement at LHCb with beam-gas imaging

    International Nuclear Information System (INIS)

    Barschel, Colin

    2014-01-01

    The luminosity is the physical quantity which relates the cross-section to the production rate in collider experiments. The cross-section being the particle physics observable of interest, a precise determination of the luminosity is required. This work presents the absolute luminosity calibration results performed at the Large Hadron Collider beauty (LHCb) experiment at CERN using a novel method based on beam-gas interactions with data acquired at a center of mass energy √(s)=8 TeV and √(s)=2.76 TeV. Reconstructed beam-gas interaction vertices in LHCb are used to measure the beam profiles, thus making it possible to determine the beams overlap integral. An important element of this work was to install and use a neon gas injection system to increase the beam-gas interaction rate. The precision reached with the beam-gas imaging method relies on the two-dimensional beam shape determination developed in this work. For such precision, the interaction vertex resolution is an important ingredient. Therefore, a new method has been developed using all reconstructed vertices in order to improve the understanding of the vertex resolution. In addition to the overlap integral, the knowledge of the colliding bunch populations is required to measure the luminosity. The determination of the bunch populations relies on LHC instruments to measure the bunch population fractions and the total beam intensity. Studies performed as part of this work resulted in a reduction of the bunch current normalization uncertainty from ±2.7% to ±0.2% and making it possible to achieve precision luminosity measurements at all LHC experiments. Furthermore, information on beam-gas interactions not originating from nominally filled bunches was analyzed to determine the charge fraction not participating in bunch collisions. The knowledge of this fraction is required to correct the total beam intensity. The reference cross-section of pp interactions with at least two tracks in the vertex detector

  17. Experimentation with low-energy positron beams

    International Nuclear Information System (INIS)

    Mills, A.P. Jr.

    1983-01-01

    The capability of studying the interactions of positrons with surfaces has recently been exploited by using ultra-high-vacuum techniques. The result has been a new understanding of how positrons interact with surfaces and because of this we are now able to make much stronger fluxes of slow positrons. The higher beam strengths in turn are opening up new possibilities for experimentation on surfaces and solids and for studying the atomic physics of positronium and positron-molecule scattering at low energies. The lectures are intended to review some of the history of this subject and to outline the present state of our knowledge of experimentation with low-energy positron beams. (orig./TW)

  18. New Measurements of Fragmentation Cross Sections from ^(56)Fe and ^(60)Ni Beams at Energies Relevant to Galactic Cosmic-Ray Propagation

    OpenAIRE

    George, J. S.; Mewaldt, R. A.; Yanasak, N. E.; Wiedenbeck, M. E.; Connell, J. J.; Audouin, L.; Bacri, C.-O.; Berthier, B.; Ferrant, L.; Rejmund, F.; Stéphan, C.; Tassan-Got, L.; Karamanis, D.; Czajkowski, S.; Boudard, A.

    2001-01-01

    Models of cosmic-ray propagation in the Galaxy rely heavily on knowledge of the nuclear fragmentation cross sections which govern spallation of heavy nuclei in the interstellar medium. Interpretation of high-precision cosmic-ray composition data such as those from the ACE and Ulysses missions requires improved cross-section data. New measurements of partial fragmentation cross sections have been made with high statistical accuracy at the GSI heavy ion synchrotron (SIS) using ^(56)Fe beams at ...

  19. Beam Based RF Voltage Measurements and Longitudinal Beam Tomography at the Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Bhat, C. M. [Fermilab; Bhat, S. [Fermilab

    2017-10-19

    Increasing proton beam power on neutrino production targets is one of the major goals of the Fermilab long term accelerator programs. In this effort, the Fermilab 8 GeV Booster synchrotron plays a critical role for at least the next two decades. Therefore, understanding the Booster in great detail is important as we continue to improve its performance. For example, it is important to know accurately the available RF power in the Booster by carrying out beam-based measurements in order to specify the needed upgrades to the Booster RF system. Since the Booster magnetic field is changing continuously measuring/calibrating the RF voltage is not a trivial task. Here, we present a beam based method for the RF voltage measurements. Data analysis is carried out using computer programs developed in Python and MATLAB. The method presented here is applicable to any RCS which do not have flat-bottom and flat-top in the acceleration magnetic ramps. We have also carried out longitudinal beam tomography at injection and extraction energies with the data used for RF voltage measurements. Beam based RF voltage measurements and beam tomography were never done before for the Fermilab Booster. The results from these investigations will be very useful in future intensity upgrades.

  20. Method for energy recovery of spent ERL beams

    Energy Technology Data Exchange (ETDEWEB)

    Marhauser, Frank; Hannon, Fay; Rimmer, Robert; Whitney, R. Roy

    2018-01-16

    A method for recovering energy from spent energy recovered linac (ERL) beams. The method includes adding a plurality of passive decelerating cavities at the beam dump of the ERL, adding one or more coupling waveguides between the passive decelerating cavities, setting an adequate external Q (Qext) to adjust to the beam loading situation, and extracting the RF energy through the coupling waveguides.

  1. Simulation-based Investigations of Electrostatic Beam Energy Analysers

    CERN Document Server

    Pahl, Hannes

    2015-01-01

    An energy analyser is needed to measure the beam energy profile behind the REX-EBIS at ISOLDE. The device should be able to operate with an accuracy of 1 V at voltages up to 30 kV. In order to find a working concept for an electrostatic energy analyser different designs were evaluated with simulations. A spherical device and its design issues are presented. The potential deformation effects of grids at high voltages and their influence on the energy resolution were investigated. First tests were made with a grid-free ring electrode device and show promising results.

  2. Beam-Profile Instrumentation for a Beam-Halo Measurement Overall Description, Operation, and Beam Data

    CERN Document Server

    Gilpatrick, J D; Day, L; Kerstiens, D; Stettler, M; Valdiviez, R

    2001-01-01

    The halo experiment presently being conducted at the Low Energy Demonstration Accelerator (LEDA) at Los Alamos National Laboratory (LANL) has specific instruments that acquire horizontally and vertically projected particle-density beam distributions out to greater than 105:1 dynamic range. We measure the core of the distributions using traditional wire scanners, and the tails of the distribution using water-cooled graphite scraping devices. The wire scanner and halo scrapers are mounted on the same moving frame whose location is controlled with stepper motors. A sequence within the Experimental Physics and Industrial Control System (EPICS) software communicates with a National Instrument LabVIEW virtual instrument to control the movement and location of the scanner/scraper assembly. Secondary electrons from the wire scanner 33 μm carbon wire and protons impinging on the scraper are both detected with a lossy-integrator electronic circuit. Algorithms implemented within EPICS and in Research Systems Interactiv...

  3. BEAM EMITTANCE MEASUREMENT TOOL FOR CEBAF OPERATIONS

    International Nuclear Information System (INIS)

    Chevtsov, Pavel; Tiefenback, Michael

    2008-01-01

    A new software tool was created at Jefferson Lab to measure the emittance of the CEBAF electron beams. The tool consists of device control and data analysis applications. The device control application handles the work of wire scanners and writes their measurement results as well as the information about accelerator settings during these measurements into wire scanner data files. The data analysis application reads these files and calculates the beam emittance on the basis of a wire scanner data processing model. Both applications are computer platform independent but are mostly used on LINUX PCs recently installed in the accelerator control room. The new tool significantly simplifies beam emittance measurement procedures for accelerator operations and contributes to a very high availability of the CEBAF machine for the nuclear physics program at Jefferson Lab.

  4. Energy composition of high-energy neutral beams on the COMPASS tokamak

    Directory of Open Access Journals (Sweden)

    Mitosinkova Klara

    2016-12-01

    Full Text Available The COMPASS tokamak is equipped with two identical neutral beam injectors (NBI for additional plasma heating. They provide a beam of deuterium atoms with a power of up to ~(2 × 300 kW. We show that the neutral beam is not monoenergetic but contains several energy components. An accurate knowledge of the neutral beam power in each individual energy component is essential for a detailed description of the beam- -plasma interaction and better understanding of the NBI heating processes in the COMPASS tokamak. This paper describes the determination of individual energy components in the neutral beam from intensities of the Doppler-shifted Dα lines, which are measured by a high-resolution spectrometer viewing the neutral beam-line at the exit of NBI. Furthermore, the divergence of beamlets escaping single aperture of the last accelerating grid is deduced from the width of the Doppler-shifted lines. Recently, one of the NBI systems was modified by the removal of the Faraday copper shield from the ion source. The comparison of the beam composition and the beamlet divergence before and after this modification is also presented.

  5. Crystal Collimation Cleaning Measurements with Proton Beams in LHC

    CERN Document Server

    Rossi, Roberto; Andreassen, Odd Oyvind; Butcher, Mark; Dionisio Barreto, Cristovao Andre; Masi, Alessandro; Mirarchi, Daniele; Montesano, Simone; Lamas Garcia, Inigo; Redaelli, Stefano; Scandale, Walter; Serrano Galvez, Pablo; Rijllart, Adriaan; Valentino, Gianluca; CERN. Geneva. ATS Department

    2016-01-01

    During this MD, performed on July 29th, 2016, bent silicon crystal were tested with proton beams for a possible usage of crystal-assisted collimation. Tests were performed at both injection energy and flat top using horizontal and vertical crystal. Loss maps with crystals at 6.5 TeV were measured.

  6. Longitudinal Beam measurements at the LHC: The LHC Beam Quality Monitor

    CERN Document Server

    Papotti, G; Follin, F; Wehrle, U

    2011-01-01

    The LHC Beam Quality Monitor is a system that measures individual bunch lengths and positions, similarly to the twin system SPS Beam Quality Monitor, from which it was derived. The pattern verification that the system provides is vital during the injection process to verify the correctness of the injected pattern, while the bunch length measurement is fed back to control the longitudinal emittance blow up performed during the energy ramp and provides a general indication of the health of the RF system. The algorithms used, the hardware implementation and the system integration in the LHC control infrastructure are presented in this paper, along with possible improvements.

  7. Emittance Measurements For Future LHC Beams Using The PS Booster Measurement Line

    CERN Document Server

    Abelleira, Jose; Mikulec, Bettina; Di Giovanni, Gian Piero; CERN. Geneva. ATS Department

    2017-01-01

    The CERN PS Booster measurement line contains three pairs of SEM grids separated by drift space that measures the beam size in both planes. The combined analysis of these grids allows calculating a value for the transverse beam emittances. The precision of such a measurement depends on the ratio of RMS beam size and wire spacing. Within the LIU-PSB upgrade the extraction kinetic energy of the PSB will be increased from the current 1.4 GeV to 2.0 GeV. This will result in smaller transverse beam sizes for some of the future beams. The present layout of the transverse emittance measurement line is reviewed to verify if it will satisfy future requirements.

  8. Antiproton beam profile measurements using Gas Electron Multipliers

    CERN Document Server

    Duarte Pinto, Serge; Spanggaard, Jens; Tranquille, Gerard

    2011-01-01

    The new beam profile measurement for the Antiproton Decelerator (AD) at CERN is based on a single Gas Electron Multiplier (GEM) with a 2D readout structure. This detector is very light, ~0.4% X_0, as required by the low energy of the antiprotons, 5.3 MeV. This overcomes the problems previously encountered with multi-wire proportional chambers (MWPC) for the same purpose, where beam interactions with the detector severely affect the obtained profiles. A prototype was installed and successfully tested in late 2010, with another five detectors now installed in the ASACUSA and AEgIS beam lines. We will provide a detailed description of the detector and discuss the results obtained. The success of these detectors in the AD makes GEM-based detectors likely candidates for upgrade of the beam profile monitors in all experimental areas at CERN. The various types of MWPC currently in use are aging and becoming increasingly difficult to maintain.

  9. Preliminary investigations on high energy electron beam tomography

    Energy Technology Data Exchange (ETDEWEB)

    Baertling, Yves; Hoppe, Dietrich; Hampel, Uwe

    2010-12-15

    In computed tomography (CT) cross-sectional images of the attenuation distribution within a slice are created by scanning radiographic projections of an object with a rotating X-ray source detector compound and subsequent reconstruction of the images from these projection data on a computer. CT can be made very fast by employing a scanned electron beam instead of a mechanically moving X-ray source. Now this principle was extended towards high-energy electron beam tomography with an electrostatic accelerator. Therefore a dedicated experimental campaign was planned and carried out at the Budker Institute of Nuclear Physics (BINP), Novosibirsk. There we investigated the capabilities of BINP's accelerators as an electron beam generating and scanning unit of a potential high-energy electron beam tomography device. The setup based on a 1 MeV ELV-6 (BINP) electron accelerator and a single detector. Besides tomographic measurements with different phantoms, further experiments were carried out concerning the focal spot size and repeat accuracy of the electron beam as well as the detector's response time and signal to noise ratio. (orig.)

  10. Feasibility study for the measurement of the longitudinal emittance of the beam in the mean energy line of the Spiral-2 accelerator; Etude de faisabilite pour la mesure de l'emittance longitudinale du faisceau dans la ligne moyenne energie de l'accelerateur primaire Spiral-2

    Energy Technology Data Exchange (ETDEWEB)

    Duperrier, R.; Uriot, D

    2006-09-15

    The author describes 3 methods for measuring beam longitudinal emittance and presents the equipment and conditions required for the measurement. The first method implies to make the phase space discrete through a set of slits coupled to a dipole and to make a measurement of the phase extension. The second method is the 3 gradients method that is based on the measurement of different packet phase extensions that are obtained through the variation of the electric field amplitude of the first beam buncher of the mean energy line. The third method consists in simulating the beam transport through the use of simulation codes and the measurement of phase extension and transverse beam emittances. The third method appears to be complementary to the first one when non-linearities in transport are no more negligible. (A.C.)

  11. Summary of Session 4 "Beam Energy"

    CERN Document Server

    Siemko, A

    2011-01-01

    In this session, the possible scenarios for the beam energy in the LHC 2011 run were discussed. The benefits for the physics reach for physics operations at s larger than 7 TeV were reviewed. The main goal was, however, to establish the necessary information for a sound risk analysis by assessing the probability of thermal runaway and evaluating the consequences of a hypothetical incident. A new technique to improve the knowledge of joint resistances of the cooper busbars and therefore the reliability of the risk analysis has also been discussed.

  12. Beam measurements of the SPS longitudinal impedance

    CERN Document Server

    Lasheen, A

    2017-01-01

    Longitudinal instabilities are one of the main limitationsin the CERN SPS to reach the beam parameters requiredfor the High Luminosity LHC project. In preparation tothe SPS upgrade, possible remedies are studied by perform-ing macroparticle simulations using the machine impedancemodel obtained from electromagnetic simulations and mea-surements. To benchmark the impedance model, the resultsof simulations are compared with various beam measure-ments. In this study, the reactive part of the impedance wasprobed by measuring the quadrupole frequency shift withintensity, obtained from bunch length oscillations at mis-matched injection into the SPS. This method was appliedover many last years to follow up the evolution of the SPSimpedance, injecting bunches with the same bunch length.A novel approach, giving significantly more information,consists in varying the injected bunch length. The compari-son of these measurements with macroparticle simulationsallowed to test the existing model and identify some missingSPS i...

  13. Precision luminosity measurement at LHCb with beam-gas imaging

    CERN Document Server

    Barschel, Colin

    The luminosity is the physical quantity which relates the cross-section to the production rate in collider experiments. The cross-section being the particle physics observable of interest, a precise determination of the luminosity is required. This work presents the absolute luminosity calibration results performed at the Large Hadron Collider beauty (LHCb) experiment at CERN using a novel method based on beam-gas interactions with data acquired at a center of mass energy $\\sqrt{s}=8$ TeV and $\\sqrt{s}=2.76$ TeV. Reconstructed beam-gas interaction vertices in LHCb are used to measure the beam profiles, thus making it possible to determine the beams overlap integral. An important element of this work was to install and use a neon gas injection system to increase the beam-gas interaction rate. The precision reached with the beam-gas imaging method relies on the two-dimensional beam shape determination developed in this work. For such precision, the interaction vertex resolution is an important ingredient. There...

  14. Enhanced piezoelectric wind energy harvesting based on a buckled beam

    Science.gov (United States)

    Zhang, Jiantao; Zhang, Jia; Shu, Chang; Fang, Zhou

    2017-05-01

    In order to improve the wind energy conversion efficiency, this study entails a concept utilizing the buckling behavior of a buckled beam to induce large amplitude oscillations in a PVDF beam harvester. Specifically, when the buckled beam subjected to the buckling load is in an unstable condition, the wind load can trigger the drastic vibration of the PVDF beam harvester. Experimental results demonstrate that the output performances of the proposed harvester are improved dramatically compared with a traditional cantilever beam harvester.

  15. Techniques for beam impedance measurements above cutoff

    International Nuclear Information System (INIS)

    Lambertson, G.R.; Jacob, A.F.; Rimmer, R.A.; Voelker, F.

    1990-08-01

    Methods for measuring beam impedance above cutoff have been very limited. For design work on the ALS we have developed two techniques that yield data in the frequency domain with high sensitivity. The first is an extension of the wire method; the second utilizes traveling TM waves to simulate the beam's fields at the wall, and thus avoids the mechanical difficulties of mounting the wire. It is also more sensitive than the other method but the interpretation is complicated by the presence of higher order modes. With either method we were able to detect resonant peaks smaller than 1 Ohm at 10 GHz

  16. Results from the RHIC Beam Energy Scan

    Science.gov (United States)

    Taranenko, A.

    2017-12-01

    The first phase of the Beam Energy Scan (BES-I) program at the Relativistic Heavy Ion Collider (RHIC) is based on Au+Au collision data collected between 2010 and 2014 at center-of-mass energies = 7.7, 11.5, 14.5, 19.6, 27, and 39 GeV. The BES-I program has four physics goals: search for the turning off of the signatures of the Quark Gluon Plasma (QGP), the search for the possible first-order phase transition between hadronic gas and QGP, the search for the possible critical end point and the study of the transport properties of the strongly interacting matter as a function of the temperature T and baryon chemical potential μB. In this article, we briefly review and discuss the main results and their understanding from the BES-I program and future plans for the BES-II program (2019-2020).

  17. Electron beam water calorimetry measurements to obtain beam quality conversion factors.

    Science.gov (United States)

    Muir, Bryan R; Cojocaru, Claudiu D; McEwen, Malcolm R; Ross, Carl K

    2017-10-01

    To provide results of water calorimetry and ion chamber measurements in high-energy electron beams carried out at the National Research Council Canada (NRC). There are three main aspects to this work: (a) investigation of the behavior of ionization chambers in electron beams of different energies with focus on long-term stability, (b) water calorimetry measurements to determine absorbed dose to water in high-energy beams for direct calibration of ion chambers, and (c) using measurements of chamber response relative to reference ion chambers, determination of beam quality conversion factors, k Q , for several ion chamber types. Measurements are made in electron beams with energies between 8 MeV and 22 MeV from the NRC Elekta Precise clinical linear accelerator. Ion chamber measurements are made as a function of depth for cylindrical and plane-parallel ion chambers over a period of five years to investigate the stability of ion chamber response and for indirect calibration. Water calorimetry measurements are made in 18 MeV and 22 MeV beams. An insulated enclosure with fine temperature control is used to maintain a constant temperature (drifts less than 0.1 mK/min) of the calorimeter phantom at 4°C to minimize effects from convection. Two vessels of different designs are used with calibrated thermistor probes to measure radiation induced temperature rise. The vessels are filled with high-purity water and saturated with H 2 or N 2 gas to minimize the effect of radiochemical reactions on the measured temperature rise. A set of secondary standard ion chambers are calibrated directly against the calorimeter. Finally, several other ion chambers are calibrated in the NRC 60 Co reference field and then cross-calibrated against the secondary standard chambers in electron beams to realize k Q factors. The long-term stability of the cylindrical ion chambers in electron beams is better (always <0.15%) than plane-parallel chambers (0.2% to 0.4%). Calorimetry measurements

  18. Tevatron beam-beam simulations at injection energy

    Energy Technology Data Exchange (ETDEWEB)

    Meiqin Xiao; Bela Erdelyi; Tanaji Sen

    2003-05-28

    Major issues at Tevatron injection are the effects of 72 long-range beam-beam interactions together with the machine nonlinearity on protons and anti-protons. We look at particle tracking calculations of Dynamic Aperture (DA) under present machine conditions. Comparisons of calculations with observations and experiments are also presented in this report.

  19. Longitudinal density modulation and energy conversion in intense beams

    International Nuclear Information System (INIS)

    Harris, J. R.; Neumann, J. G.; Tian, K.; O'Shea, P. G.

    2007-01-01

    Density modulation of charged particle beams may occur as a consequence of deliberate action, or may occur inadvertently because of imperfections in the particle source or acceleration method. In the case of intense beams, where space charge and external focusing govern the beam dynamics, density modulation may, under some circumstances, be converted to velocity modulation, with a corresponding conversion of potential energy to kinetic energy. Whether this will occur depends on the properties of the beam and the initial modulation. This paper describes the evolution of discrete and continuous density modulations on intense beams and discusses three recent experiments related to the dynamics of density-modulated electron beams

  20. 2D potential measurements by applying automatic beam adjustment system to heavy ion beam probe diagnostic on the Large Helical Device

    International Nuclear Information System (INIS)

    Shimizu, A.; Ido, T.; Kato, S.; Hamada, Y.; Kurachi, M.; Makino, R.; Nishiura, M.; Nishizawa, A.

    2014-01-01

    Two-dimensional potential profiles in the Large Helical Device (LHD) were measured with heavy ion beam probe (HIBP). To measure the two-dimensional profile, the probe beam energy has to be changed. However, this task is not easy, because the beam transport line of LHD-HIBP system is very long (∼20 m), and the required beam adjustment consumes much time. To reduce the probe beam energy adjustment time, an automatic beam adjustment system has been developed. Using this system, required time to change the probe beam energy is dramatically reduced, such that two-dimensional potential profiles were able to be successfully measured with HIBP by changing the probe beam energy shot to shot

  1. Comparative Dosimetric Characterization for Different Types of Detectors in High-Energy Electron Beams

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Chang Yeol; Kim, Woo Chul; Kim, Hun Jeong; Huh, Hyun Do [Inha University, Incheon (Korea, Republic of); Park, Seungwoo; Choi, Sang Hyoun; Kim, Kum Bae [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Min, Chul Kee [Soonchunhyang University, Cheonan, Chung-nam (Korea, Republic of); Kim, Seong Hoon [Hanyang University, Seoul (Korea, Republic of); Shin, Dong Oh [Kyunghee University, Seoul (Korea, Republic of)

    2017-02-15

    The purpose of this study is to perform a comparison and on analysis of measured dose factor values by using various commercially available high-energy electron beam detectors to measure dose profiles and energy property data. By analyzing the high-energy electron beam data from each detector, we determined the optimal detector for measuring electron beams in clinical applications. The dose linearity, dose-rate dependence, percentage depth dose, and dose profile of each detector were measured to evaluate the dosimetry characteristics of high-energy electron beams. The dose profile and the energy characteristics of high-energy electron beams were found to be different when measured by different detectors. Through comparison with other detectors based on the analyzed data, the microdiamond detector was found to have outstanding dose linearity, a low dose-rate dependency, and a small effective volume. Thus, this detector has outstanding spatial resolution and is the optimal detector for measuring electron beams. Radiation therapy results can be improved and related medical accidents can be prevented by using the procedure developed in this research in clinical practice for all beam detectors when measuring the electron beam dose.

  2. Application of activity pencil beam algorithm using measured distribution data of positron emitter nuclei for therapeutic SOBP proton beam

    International Nuclear Information System (INIS)

    Miyatake, Aya; Nishio, Teiji

    2013-01-01

    Purpose: Recently, much research on imaging the clinical proton-irradiated volume using positron emitter nuclei based on target nuclear fragment reaction has been carried out. The purpose of this study is to develop an activity pencil beam (APB) algorithm for a simulation system for proton-activated positron-emitting imaging in clinical proton therapy using spread-out Bragg peak (SOBP) beams.Methods: The target nuclei of activity distribution calculations are 12 C nuclei, 16 O nuclei, and 40 Ca nuclei, which are the main elements in a human body. Depth activity distributions with SOBP beam irradiations were obtained from the material information of ridge filter (RF) and depth activity distributions of compounds of the three target nuclei measured by BOLPs-RGp (beam ON-LINE PET system mounted on a rotating gantry port) with mono-energetic Bragg peak (MONO) beam irradiations. The calculated data of depth activity distributions with SOBP beam irradiations were sorted in terms of kind of nucleus, energy of proton beam, SOBP width, and thickness of fine degrader (FD), which were verified. The calculated depth activity distributions with SOBP beam irradiations were compared with the measured ones. APB kernels were made from the calculated depth activity distributions with SOBP beam irradiations to construct a simulation system using the APB algorithm for SOBP beams.Results: The depth activity distributions were prepared using the material information of RF and the measured depth activity distributions with MONO beam irradiations for clinical therapy using SOBP beams. With the SOBP width widening, the distal fall-offs of depth activity distributions and the difference from the depth dose distributions were large. The shapes of the calculated depth activity distributions nearly agreed with those of the measured ones upon comparison between the two. The APB kernels of SOBP beams were prepared by making use of the data on depth activity distributions with SOBP beam

  3. Theoretical study of cylindrical energy analyzers for MeV range heavy ion beam probes

    International Nuclear Information System (INIS)

    Fujisawa, A.; Hamada, Y.

    1993-07-01

    A cylindrical energy analyzer with drift spaces is shown to have a second order focusing for beam incident angle when the deflection angle is properly chosen. The analyzer has a possibility to be applied to MeV range heavy ion beam probes, and will be also available for accurate particle energy measurements in many other fields. (author)

  4. Low-Energy Run of Fermilab Electron Cooler's Beam Generation System

    Energy Technology Data Exchange (ETDEWEB)

    Prost, L.R.; Shemyakin, A.; /Fermilab; Fedotov, A.; Kewisch, J.; /Brookhaven

    2011-03-14

    In the context of the evaluation of possibly using the Fermilab Electron Cooler for the proposed low-energy RHIC run at BNL, operating the cooler at 1.6 MeV electron beam energy was tested in a short beam line configuration. The main conclusion of this feasibility study is that the cooler's beam generation system is suitable for BNL needs. The beam recirculation was stable for all tested parameters. In particular, a beam current of 0.38 A was achieved with the cathode magnetic field up to the maximum value presently available of 250 G. The energy ripple was measured to be 40 eV. A striking difference with running the 4.3 MeV beam (nominal for operation at FNAL) is that no unprovoked beam recirculation interruptions were observed. Electron cooling proposed to increase the luminosity of the RHIC collider for heavy ion beam energies below 10 GeV/nucleon [1] needs a good quality, 0.9-5 MeV electron beam. Preliminary design studies indicate that the scheme of the Recycler's electron cooler at FNAL is suitable for low-energy RHIC cooling and most parts of the cooler can be re-used after the end of the Tevatron Run II. To analyze issues related to the generation of the electron beam in the energy recovery mode and to gain experience with the beam transport at lower beam energy, a dedicated study was performed at FNAL with a beam run through a short beam line (so called U-bend). This report summarizes our findings and observations in the course of the measurements.

  5. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Mass analyzed highly charged ion beams of energy ranging from a few keV to a few MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply charged ion ...

  6. ECR ion source based low energy ion beam facility

    Indian Academy of Sciences (India)

    Abstract. Mass analyzed highly charged ion beams of energy ranging from a few keV to a few. MeV plays an important role in various aspects of research in modern physics. In this paper a unique low energy ion beam facility (LEIBF) set up at Nuclear Science Centre (NSC) for providing low and medium energy multiply ...

  7. Measurement with hadron beams at COMPASS

    CERN Document Server

    Ferrero, Andrea

    2005-01-01

    The physics program of the COMPASS experiment at CERN focuses on the investigation of the hadron structure and spectroscopy, using both leptonic and hadronic probes. The COMPASS experiment has collected so far mostly data with polarized muon beams of 160 GeV, but also a pilot data taking with negative hadron beams of 190 GeV has been successfully completed at the end of the 2004 run. The main physics objectives of this pilot run are the study of soft pion-nuclei interactions. The predictions of the Chiral Perturbation Theory for the electric and magnetic polarizabilities of the pion will be verified through the study of the Primakoff scattering of 190 GeV pions on thin lead targets. A sample corresponding to an integrated beam flux of more than 10$^{11}$ pions has been collected for this purpose, and an equivalent sample with the muon beam of 190 GeV has been collected in the same experimental conditions to correct possible systematic effects. In parallel to the polarizability measurements, first data have al...

  8. Radioactive ion beams at the Bevalac: Greatly enhanced fragment separation for high energy beams

    International Nuclear Information System (INIS)

    Feinberg, B.; Kalnins, J.G.; Krebs, G.F.

    1990-09-01

    Radioactive beams are routinely produced at the Bevalac by the fragmentation process. High energy beams (energies ∼ 800 MeV/u) produce fragments with nearly the original beam momentum, forming a radioactive ion beam. A new beamline is being constructed which will provide resolution for ions approaching the mass 100 region, compared to the present mass 20 capability, by strongly increasing the dispersion and also increasing the beam size for easier tuning and more effective collimation. In addition, the angular acceptance has been more than doubled. Details of the design will be presented. 6 refs., 4 figs., 1 tab

  9. Online measurement of electron beam parameters by image processing

    International Nuclear Information System (INIS)

    Tyagi, Y.; Puntambekar, T.A.

    2010-01-01

    The basic image acquisition software which was developed earlier has been recently upgraded to support online measurement of beam centroid, beam height and beam width from the diagnostic devices namely fluorescent screen beam profile monitors and beam slit monitor installed in Transport Line -1(TL-1) at Indus Accelerator Complex at RRCAT, Indore. The online measurement of these electron beam parameters has helped the Indus operation team to take necessary corrective action if required before injection of the electron beam into booster synchrotron. This paper presents the methodology adopted for online measurement of above parameters in the software. (author)

  10. Charged fusion product analysis as diagnostics in high-energy deuterium beams

    International Nuclear Information System (INIS)

    Bayetti, P.; Bottiglioni, F.; Martin, G.; Pamela, J.

    1986-01-01

    The detection of protons (3 MeV) and tritons (1 MeV) originating from D--D fusion reactions are presented as a tool for inferring the main features of a powerful deuterium neutral beam. By an energy analysis, beam species content, neutralization, and power transmission efficiencies have been measured. Using a localization detector, a method for measuring beam profiles has been developed

  11. Charged fusion product analysis as diagnostics in high energy deuterium beams

    International Nuclear Information System (INIS)

    Bayetti, P.; Bottiglioni, F.; Martin, G.; Pamela, J.

    1985-05-01

    The detection of protons (3 MeV) and tritons (1 MeV) originating from D-D fusion reactions are presented as a tool for inferring the main features of a powerful deuterium neutral beam. By an energy analysis, beam species content, neutralisation and power transmission efficiencies have been measured. Using a localisation detector, a method for measuring beam profiles has been developed

  12. Measuring industrial energy savings

    International Nuclear Information System (INIS)

    Kelly Kissock, J.; Eger, Carl

    2008-01-01

    Accurate measurement of energy savings from industrial energy efficiency projects can reduce uncertainty about the efficacy of the projects, guide the selection of future projects, improve future estimates of expected savings, promote financing of energy efficiency projects through shared-savings agreements, and improve utilization of capital resources. Many efforts to measure industrial energy savings, or simply track progress toward efficiency goals, have had difficulty incorporating changing weather and production, which are frequently major drivers of plant energy use. This paper presents a general method for measuring plant-wide industrial energy savings that takes into account changing weather and production between the pre and post-retrofit periods. In addition, the method can disaggregate savings into components, which provides additional resolution for understanding the effectiveness of individual projects when several projects are implemented together. The method uses multivariable piece-wise regression models to characterize baseline energy use, and disaggregates savings by taking the total derivative of the energy use equation. Although the method incorporates search techniques, multi-variable least-squares regression and calculus, it is easily implemented using data analysis software, and can use readily available temperature, production and utility billing data. This is important, since more complicated methods may be too complex for widespread use. The method is demonstrated using case studies of actual energy assessments. The case studies demonstrate the importance of adjusting for weather and production between the pre- and post-retrofit periods, how plant-wide savings can be disaggregated to evaluate the effectiveness of individual retrofits, how the method can identify the time-dependence of savings, and limitations of engineering models when used to estimate future savings

  13. Non-perturbative measurement of low-intensity charged particle beams

    Science.gov (United States)

    Fernandes, M.; Geithner, R.; Golm, J.; Neubert, R.; Schwickert, M.; Stöhlker, T.; Tan, J.; Welsch, C. P.

    2017-01-01

    Non-perturbative measurements of low-intensity charged particle beams are particularly challenging to beam diagnostics due to the low amplitude of the induced electromagnetic fields. In the low-energy antiproton decelerator (AD) and the future extra low energy antiproton rings at CERN, an absolute measurement of the beam intensity is essential to monitor the operation efficiency. Superconducting quantum interference device (SQUID) based cryogenic current comparators (CCC) have been used for measuring slow charged beams in the nA range, showing a very good current resolution. But these were unable to measure fast bunched beams, due to the slew-rate limitation of SQUID devices and presented a strong susceptibility to external perturbations. Here, we present a CCC system developed for the AD machine, which was optimised in terms of its current resolution, system stability, ability to cope with short bunched beams, and immunity to mechanical vibrations. This paper presents the monitor design and the first results from measurements with a low energy antiproton beam obtained in the AD in 2015. These are the first CCC beam current measurements ever performed in a synchrotron machine with both coasting and short bunched beams. It is shown that the system is able to stably measure the AD beam throughout the entire cycle, with a current resolution of 30 {nA}.

  14. Measurement with a free neutron beam of absolute neutron-proton forward elastic-scattering differential cross section at intermediate energies

    International Nuclear Information System (INIS)

    Terrien, Y.; Lugol, J.C.; Saudinos, J.

    1987-01-01

    The differential cross section in free n-p forward elastic scattering has been measured for incident neutron energies of 378, 481, 582, 683, 784, 884, and 1085 MeV and for momentum transfer 0.01 2 . The experiment used a recoil-detector ionization chamber which served at the same time as a gas target. Special care has been taken to obtain a precise absolute normalization

  15. Linac3 LEBT beam measurements during the 2014-2015 Argon ion run

    CERN Document Server

    Bellodi, Giulia; Maintrot, Marc; Toivanen, Ville Aleksi; CERN. Geneva. ATS Department

    2016-01-01

    Between Spring 2014 and Spring 2015, LINAC3 delivered a beam of Argon ions. A campaign of beam studies was launched with the aim of better understanding the present limitations in the machine performance in the framework of the requested intensity goals as defined by the LHC Injectors Upgrade project. Measurements were mostly focused on beam characterization in the low energy part of Linac3 (LEBT), where performance in operation is mostly limited (in terms of beam transmission). Systematic quadrupole scans provided indirect measurement of the beam transverse emittance and were used as input to improve and refine the accelerator and beam description parameters used in simulations. IBSimu studies of beam formation and extraction at the source were interfaced with particle tracking with the 3D code PATH, and the resulting predictions found good validation in the beam measurements taken during this campaign.

  16. Cherenkov detector for beam quality measurement

    Science.gov (United States)

    Orfanelli, S.; CMS Collaboration

    2016-07-01

    A new detector to measure the machine induced background at larger radii has been developed and installed in the CMS experiment at the LHC. It consists of forty modules, each comprising a quartz bar read out by a photomultiplier tube. Since Cherenkov radiation is emitted in a forward cone around the charged particle trajectory, these detectors can distinguish between the arrival directions of the machine induced background and the collision products. The back-end electronics consists of a uTCA readout with excellent time resolution. The installation in the CMS is described and first commissioning measurements with the LHC beams in Run II are presented.

  17. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    Energy Technology Data Exchange (ETDEWEB)

    Valerio-Lizarraga, Cristhian A., E-mail: cristhian.alfonso.valerio.lizarraga@cern.ch [CERN, Geneva (Switzerland); Departamento de Investigación en Física, Universidad de Sonora, Hermosillo (Mexico); Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard [CERN, Geneva (Switzerland); Leon-Monzon, Ildefonso [Facultad de Ciencias Fisico-Matematicas, Universidad Autónoma de Sinaloa, Culiacan (Mexico); Midttun, Øystein [CERN, Geneva (Switzerland); University of Oslo, Oslo (Norway)

    2014-02-15

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H{sup −} beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree.

  18. Space charge compensation in the Linac4 low energy beam transport line with negative hydrogen ions

    International Nuclear Information System (INIS)

    Valerio-Lizarraga, Cristhian A.; Lallement, Jean-Baptiste; Lettry, Jacques; Scrivens, Richard; Leon-Monzon, Ildefonso; Midttun, Øystein

    2014-01-01

    The space charge effect of low energy, unbunched ion beams can be compensated by the trapping of ions or electrons into the beam potential. This has been studied for the 45 keV negative hydrogen ion beam in the CERN Linac4 Low Energy Beam Transport using the package IBSimu [T. Kalvas et al., Rev. Sci. Instrum. 81, 02B703 (2010)], which allows the space charge calculation of the particle trajectories. The results of the beam simulations will be compared to emittance measurements of an H − beam at the CERN Linac4 3 MeV test stand, where the injection of hydrogen gas directly into the beam transport region has been used to modify the space charge compensation degree

  19. Measurements of high-current electron beams from X pinches and wire array Z pinches

    International Nuclear Information System (INIS)

    Shelkovenko, T. A.; Pikuz, S. A.; Blesener, I. C.; McBride, R. D.; Bell, K. S.; Hammer, D. A.; Agafonov, A. V.; Romanova, V. M.; Mingaleev, A. R.

    2008-01-01

    Some issues concerning high-current electron beam transport from the X pinch cross point to the diagnostic system and measurements of the beam current by Faraday cups are discussed. Results of computer simulation of electron beam propagation from the pinch to the Faraday cup give limits for the measured current for beams having different energy spreads. The beam is partially neutralized as it propagates from the X pinch to a diagnostic system, but within a Faraday cup diagnostic, space charge effects can be very important. Experimental results show evidence of such effects.

  20. 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

  1. 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

  2. Choice of theoretical model for beam scattering at accelerator output foil for particle energy determination

    International Nuclear Information System (INIS)

    Balagyra, V.S.; Ryabka, P.M.

    1999-01-01

    For measuring the charged particle energy calculations of mean square angles of electron beam multiple Coulomb scattering at output combined accelerator target were undertaken according to seven theoretical models. Mollier method showed the best agreement with experiments

  3. Electron beam directed energy device and methods of using same

    Science.gov (United States)

    Retsky, Michael W.

    2007-10-16

    A method and apparatus is disclosed for an electron beam directed energy device. The device consists of an electron gun with one or more electron beams. The device includes one or more accelerating plates with holes aligned for beam passage. The plates may be flat or preferably shaped to direct each electron beam to exit the electron gun at a predetermined orientation. In one preferred application, the device is located in outer space with individual beams that are directed to focus at a distant target to be used to impact and destroy missiles. The aimings of the separate beams are designed to overcome Coulomb repulsion. A method is also presented for directing the beams to a target considering the variable terrestrial magnetic field. In another preferred application, the electron beam is directed into the ground to produce a subsurface x-ray source to locate and/or destroy buried or otherwise hidden objects including explosive devices.

  4. Fusion reaction using low energy neutron-excess nucleus beam

    International Nuclear Information System (INIS)

    Fukuda, Tomokazu

    1994-01-01

    The present state and the plan of the experiment of measuring the fusion reaction near barriers by using neutron-excess nucleus beam, which has been advanced at RIKEN are reported. One of the purposes of this experiment is the feasibility investigation of the fusion reaction by using neutron-excess nuclei, which is indispensable for synthesizing superheavy elements. It is intended to systematically explore some enhancing mechanism in the neutron-excess nuclei which are unfavorable in beam intensity. This research can become the good means to prove the dynamic behavior of the neutrons on the surfaces of nuclei in reaction. The fusion reaction of 27 Al + Au was measured by using the stable nucleus beam of 27 Al, and the results are shown. In order to know the low energy fusion reaction of 11 Li and 11 Be which are typical halo nuclei, the identification by characteristic α ray of composite nuclei is carried out in 7,9,11 Li + 209 Bi and 9,10,11 Be + 208 Pb. A new detector having high performance, New MUSIC, is being developed. As the experiment by using this detector, the efficient measurement of the fusion reaction by using heavy neutron-excess nuclei up to Ni is considered. An example of 8 Li + α → 11 B + n reaction for celestial body physics is mentioned. (K.I.)

  5. Calculated intensity of high-energy neutron beams

    International Nuclear Information System (INIS)

    Mustapha, B.; Nolen, J.A.; Back, B.B.

    2004-01-01

    The flux, energy and angular distributions of high-energy neutrons produced by in-flight spallation and fission of a 400 MeV/A 238 U beam and by the break-up of a 400 MeV/A deuteron beam are calculated. In both cases very intense secondary neutron beams are produced, peaking at zero degrees, with a relatively narrow energy spread. Such secondary neutron beams can be produced with the primary beams from the proposed rare isotope accelerator driver linac. The break-up of a 400 kW deuteron beam on a liquid-lithium target can produce a neutron flux of >10 10 neutrons/cm 2 /s at a distance of 10 m from the target

  6. Neutron spectroscopy measurements and modeling of neutral beam heating fast ion dynamics

    International Nuclear Information System (INIS)

    Hellesen, C; Sunden, E Andersson; Conroy, S; Ericsson, G; Johnson, M Gatu; Hjalmarsson, A; Kaellne, J; Ronchi, E; Sjoestrand, H; Weiszflog, M; Albergante, M; Ballabio, L; Gorini, G; Tardocchi, M; Giacomelli, L; Jenkins, I; Voitsekhovitch, I

    2010-01-01

    The energy spectrum of the neutron emission from beam-target reactions in fusion plasmas at the Joint European Torus (JET) has been investigated. Different beam energies as well as injection angles were used. Both measurements and simulations of the energy spectrum were done. The measurements were made with the time-of-flight spectrometer TOFOR. Simulations of the neutron spectrum were based on first-principle calculations of neutral beam deposition profiles and the fast ion slowing down in the plasma using the code NUBEAM, which is a module of the TRANSP package. The shape of the neutron energy spectrum was seen to vary significantly depending on the energy of the beams as well as the injection angle and the deposition profile in the plasma. Cross validations of the measured and modeled neutron energy spectra were made, showing a good agreement for all investigated scenarios.

  7. Mass and velocity distributions of low energy cluster beams

    Energy Technology Data Exchange (ETDEWEB)

    Compagnini, Giuseppe [Dipartimento di Scienze Chimiche Universita di Catania and MATIS-INFM, Viale A. Doria 6 Catania 95125 (Italy)]. E-mail: gcompagnini@unict.it; D' Urso, Luisa [Dipartimento di Scienze Chimiche Universita di Catania and MATIS-INFM, Viale A. Doria 6 Catania 95125 (Italy); Puglisi, Orazio [Dipartimento di Scienze Chimiche Universita di Catania and MATIS-INFM, Viale A. Doria 6 Catania 95125 (Italy)

    2006-07-15

    We have recently generated several low energy cluster beams by using a laser vaporization source and a pulsed He stream. This has been done both for covalent (silicon and carbon) and metallic (gold) materials. In this work we present a simple procedure to carefully measure the speed and speed distribution of the obtained clusters with the help of an orthogonal time of flight mass spectrometer. Results show average speed values in the range 700-1000 m/s with a mild variation by changing the gas backing pressure and the cluster mass inside each cluster train. Detailed speed distributions for each cluster's mass will be given.

  8. Laser beam complex amplitude measurement by phase diversity.

    Science.gov (United States)

    Védrenne, Nicolas; Mugnier, Laurent M; Michau, Vincent; Velluet, Marie-Thérèse; Bierent, Rudolph

    2014-02-24

    The control of the optical quality of a laser beam requires a complex amplitude measurement able to deal with strong modulus variations and potentially highly perturbed wavefronts. The method proposed here consists in an extension of phase diversity to complex amplitude measurements that is effective for highly perturbed beams. Named camelot for Complex Amplitude MEasurement by a Likelihood Optimization Tool, it relies on the acquisition and processing of few images of the beam section taken along the optical path. The complex amplitude of the beam is retrieved from the images by the minimization of a Maximum a Posteriori error metric between the images and a model of the beam propagation. The analytical formalism of the method and its experimental validation are presented. The modulus of the beam is compared to a measurement of the beam profile, the phase of the beam is compared to a conventional phase diversity estimate. The precision of the experimental measurements is investigated by numerical simulations.

  9. Characterization of low energy radioactive beams using direct reactions

    DEFF Research Database (Denmark)

    Johansen, J.G.; Fraser, M.A.; Bildstein, V.

    2013-01-01

    of an accelerated radioactive beam produced at ISOLDE. We use data from an experiment with an 11Be beam incident on a deuteron target producing 10Be from a (d,t) reaction. The T-REX Si detector array was used for particle detection, but the technique is applicable for other setups.......We demonstrate a new technique to determine the beam structure of low energy radioactive beams using coincidence events from a direct reaction. The technique will be described and tested using Geant4 simulations. We use the technique to determine for the first time the width, divergence and energy...

  10. The energy stabilization for the SLC scavenger beam

    International Nuclear Information System (INIS)

    Hsu, Ian; Browne, M.; Himel, T.; Humphrey, R.; Jobe, K.; Ross, M.; Pellegrin, J.L.; Seeman, J.

    1990-08-01

    The energy of the SLC scavenger beam which is used to produce positrons must be carefully maintained so that the beam can be transported through the collimators in the dispersive region of the extraction line which leads from the Linac to the positron target. A feedforward control loop has been developed to compensate the energy fluctuations due to the beam intensity fluctuations. The loop detects the beam intensities in the damping rings and then calculates how much energy needs to be compensated due to beam loading effects. The energy is corrected by adjusting the acceleration phases of two sets of klystrons right before the extraction. Because there is feedback loop using the same controls, their interaction needs to be carefully treated. This paper presents an overview of the feedforward algorithms. 3 figs

  11. Dual energy scanning beam X-radiography

    Science.gov (United States)

    Wojcik, Randolph Frank

    Dual energy X-radiography is a method first developed in the mid-1970's by which one uses the information contained in the energy spectrum of the transmitted X-ray flux through an object. With this information one can distinguish the types of materials present in a radiograph and thus allow a computer to subtract them from the image enhancing the contrast of the remaining materials. Using this method, one can see details, which would have been hidden by overlying structures of other materials such as seen in radiographs of parts, made up of mixtures of metals and composites. There is also great interest in this technique for medical imaging of the chest where images of the organs are significantly improved by subtracting the bones. However, even with the enhanced capabilities realized with this technique, the majority of X-radiography systems only measures the bulk transmitted X-ray intensity and ignores the information contained in the energy spectrum. This is due to the added expense, time requirements, and registration problems incurred using standard radiographic methods to obtain dual energy radiographs. This dissertation describes a novel method which overcomes these problems and allows one to perform inexpensive, near real time, single shot dual energy X-radiography. The work of this thesis resulted in US patent #5,742,660.

  12. On Particle Production for High Energy Neutrino Beams

    CERN Document Server

    Bonesini, M; Marchionni, A; Pietropaolo, F

    2001-01-01

    Analytical formulae for the calculation of secondary particle yields in p-A interactions are given. These formulae can be of great practical importance for fast calculations of neutrino fluxes and for designing new neutrino beam-lines. The formulae are based on a parameterization of the inclusive invariant cross sections for secondary particle production measured in p-Be interactions. Data collected in different energy ranges and kinematic regions are used. The accuracy of the fit to the data with the empirical formulae adopted is within the experimental uncertainties. Prescriptions to extrapolate this parameterization to finite targets and to targets of different materials are given. The results obtained are then used as an input for the simulation of neutrino beams. We show that our approach describes well the main characteristics of measured neutrino spectra at CERN. Thus it may be used in fast simulations aiming at the optimisation of the long-baseline neutrino beams at CERN and FNAL. In particular we wil...

  13. Low-energy beam transport studies supporting the spallation neutron source 1-MW beam operation.

    Science.gov (United States)

    Han, B X; Kalvas, T; Tarvainen, O; Welton, R F; Murray, S N; Pennisi, T R; Santana, M; Stockli, M P

    2012-02-01

    The H(-) injector consisting of a cesium enhanced RF-driven ion source and a 2-lens electrostatic low-energy beam transport (LEBT) system supports the spallation neutron source 1 MW beam operation with ∼38 mA beam current in the linac at 60 Hz with a pulse length of up to ∼1.0 ms. In this work, two important issues associated with the low-energy beam transport are discussed: (1) inconsistent dependence of the post-radio frequency quadrupole accelerator beam current on the ion source tilt angle and (2) high power beam losses on the LEBT electrodes under some off-nominal conditions compromising their reliability.

  14. Beam structure and transverse emittance studies of high-energy ion beams

    International Nuclear Information System (INIS)

    Saadatmand, K.; Johnson, K.F.; Schneider, J.D.

    1991-01-01

    A visual diagnostic technique has been developed to monitor and study ion beam structure shape and size along a transport line. In this technique, a commercially available fluorescent screen is utilized in conjunction with a video camera. This visual representation of the beam structure is digitized and enhanced through use of false-color coding and displayed on a TV monitor for on-line viewing. Digitized information is stored for further off-line processing (e.g., extraction of beam profiles). An optional wire grid placed upstream of the fluor screen adds the capability of transverse emittance (or angular spread) measurement to this technique. This diagnostic allows real-time observation of the beam response to parameter changes (e.g., evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position). 3 refs., 5 figs

  15. Beam structure and transverse emittance studies of high-energy ion beams

    Science.gov (United States)

    Saadatmand, K.; Johnson, K. F.; Schneider, J. D.

    1991-05-01

    A visual diagnostic technique was developed to monitor and study ion beam structure shape and size along a transport line. In this technique, a commercially available fluorescent screen is utilized in conjunction with a video camera. This visual representation of the beam structure is digitized and enhanced through use of false color coding and displayed on a TV monitor for on-line viewing. Digitized information is stored for further off-line processing (e.g., extraction of beam profiles). An optional wire grid placed upstream of the fluor screen adds the capability of transverse emittance (or angular spread) measurement to this technique. This diagnostic allows real time observation of the beam response to parameter changes (e.g., evolution of the beam structure, shifts in the beam intensity at various spatial locations within the beam perimeter, and shifts in the beam center and position).

  16. Cryogenic current comparators for precise ion beam current measurements

    International Nuclear Information System (INIS)

    Kurian, Febin

    2015-01-01

    The planned Facility for Antiproton and Ion Research (FAIR) at GSI has to cope with a wide range of beam intensities in its high-energy beam transport systems and in the storage rings. To meet the requirements of a non-intercepting intensity measurement down to nA range, it is planned to install a number of Cryogenic Current Comparator (CCC) units at different locations in the FAIR beamlines. In this work, the first CCC system for intensity measurement of heavy ion beams, which was developed at GSI, was re-commissioned and upgraded to be used as a 'GSI - CCC prototype' for extensive optimization and development of an improved CCC for FAIR. After installation of a new SQUID sensor and related electronics, as well as implementation of improved data acquisition components, successful beam current measurements were performed at a SIS18 extraction line. The measured intensity values were compared with those of a Secondary Electron Monitor (SEM). Furthermore, the spill-structure of a slowly extracted beam was measured and analyzed, investigating its improvement due to bunching during the slow-extraction process. Due to the extreme sensitivity of the superconducting sensor, the determined intensity values as well as the adjustment of the system for optimal performance are strongly influenced by the numerous noise sources of the accelerators environment. For this reason, detailed studies of different effects caused by noise have been carried out, which are presented together with proposals to reduce them. Similarly, studies were performed to increase the dynamic range and overcome slew rate limitations, the results of which are illustrated and discussed as well. By combining the various optimizations and characterizations of the GSI CCC prototype with the experiences made during beam operation, criteria for a more efficient CCC System could be worked out, which are presented in this work. The details of this new design are worked out with respect to the

  17. Cryogenic Beam Screens for High-Energy Particle Accelerators

    CERN Document Server

    Baglin, V; Tavian, L; van Weelderen, R

    2013-01-01

    Applied superconductivity has become a key enabling technology for high-energy particle accelerators, thus making them large helium cryogenic systems operating at very low temperature. The circulation of high-intensity particle beams in these machines generates energy deposition in the first wall through different processes. For thermodynamic efficiency, it is advisable to intercept these beam-induced heat loads, which may be large in comparison with cryostat heat in-leaks, at higher temperature than that of the superconducting magnets of the accelerator, by means of beam screens located in the magnet apertures. Beam screens may also be used as part of the ultra-high vacuum system of the accelerator, by sheltering the gas molecules cryopumped on the beam pipe from impinging radiation and thus avoiding pressure runaway. Space being extremely tight in the magnet apertures, cooling of the long, slender beam screens also raises substantial problems in cryogenic heat transfer and fluid flow. We present sizing rule...

  18. Beam energy scan with asymmetric collision at RHIC

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Alessi, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Beebe, E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brennan, J. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Brown, K. A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Butler, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Connolly, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); D Ottavio, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Drees, K. A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gardner, C. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gassner, D. M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Gu, X. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hao, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Harvey, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hayes, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Huang, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Hulsart, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ingrassia, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Jamilkowski, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Laster, J. S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Litvinenko, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Luo, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Mapes, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marr, G. J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); McIntyre, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Mernick, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Michnoff, R. [Brookhaven National Lab. (BNL), Upton, NY (United States); Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Morris, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Naylor, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Nemesure, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pinayev, I. [Brookhaven National Lab. (BNL), Upton, NY (United States); Ranjbar, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Raparia, D. [Brookhaven National Lab. (BNL), Upton, NY (United States); Robert-Demolaize, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Roser, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sampson, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Schoefer, V. [Brookhaven National Lab. (BNL), Upton, NY (United States); Severino, F. [Brookhaven National Lab. (BNL), Upton, NY (United States); Shrey, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Smith, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tepikian, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Than, Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); thieberger, P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tuozzolo, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wang, G. [Brookhaven National Lab. (BNL), Upton, NY (United States); Wu, Q. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zaltsman, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zeno, K. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhang, S. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhang, W. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2016-11-15

    A beam energy scan of deuteron-gold collision, with center-of-mass energy at 19.6, 39, 62.4 and 200.7 GeV/n, was performed at the Relativistic Heavy Ion Collider in 2016 to study the threshold for quark-gluon plasma (QGP) production. The lattice, RF, stochastic cooling and other subsystems were in different configurations for the various energies. The operational challenges changed with every new energy. The operational experience at each energy, the operation performance, highlights and lessons of the beam energy scan are reviewed in this report.

  19. High energy focused ion beam lithography using P-beam writing

    International Nuclear Information System (INIS)

    Glass, Gary A.; Rout, Bibhudutta; Dymnikov, Alexander D.; Greco, Richard R.; Kamal, Mithun; Reinhardt, James R.; Peeples, John A.

    2005-01-01

    The term 'P-beam writing' is used to describe the technique of using focused high energy proton microbeams for micro or nanofabrication applications. The P-beam technique can be used to rapidly fabricate three-dimensional, high aspect ratio microstructures in a variety of materials without the use of masks and it is proving to be a versatile lithographic method. Recent developments in the application P-beam writing of microstructures at the Louisiana Accelerator Center are presented

  20. Absorbed-dose beam quality conversion factors for cylindrical chambers in high energy photon beams.

    Science.gov (United States)

    Seuntjens, J P; Ross, C K; Shortt, K R; Rogers, D W

    2000-12-01

    Recent working groups of the AAPM [Almond et al., Med. Phys. 26, 1847 (1999)] and the IAEA (Andreo et al., Draft V.7 of "An International Code of Practice for Dosimetry based on Standards of Absorbed Dose to Water," IAEA, 2000) have described guidelines to base reference dosimetry of high energy photon beams on absorbed dose to water standards. In these protocols use is made of the absorbed-dose beam quality conversion factor, kQ which scales an absorbed-dose calibration factor at the reference quality 60Co to a quality Q, and which is calculated based on state-of-the-art ion chamber theory and data. In this paper we present the measurement and analysis of beam quality conversion factors kQ for cylindrical chambers in high-energy photon beams. At least three chambers of six different types were calibrated against the Canadian primary standard for absorbed dose based on a sealed water calorimeter at 60Co [TPR10(20)=0.572, %dd(10)x=58.4], 10 MV [TPR10(20)=0.682, %dd(10)x=69.6), 20 MV (TPR10(20)=0.758, %dd(10)x= 80.5] and 30 MV [TPR10(20) = 0.794, %dd(10)x= 88.4]. The uncertainty on the calorimetric determination of kQ for a single chamber is typically 0.36% and the overall 1sigma uncertainty on a set of chambers of the same type is typically 0.45%. The maximum deviation between a measured kQ and the TG-51 protocol value is 0.8%. The overall rms deviation between measurement and the TG-51 values, based on 20 chambers at the three energies, is 0.41%. When the effect of a 1 mm PMMA waterproofing sleeve is taken into account in the calculations, the maximum deviation is 1.1% and the overall rms deviation between measurement and calculation 0.48%. When the beam is specified using TPR10(20), and measurements are compared with kQ values calculated using the version of TG-21 with corrected formalism and data, differences are up to 1.6% when no sleeve corrections are taken into account. For the NE2571 and the NE2611A chamber types, for which the most literature data are

  1. Studies of space charge effects on operating electron beam ion trap at low electron beam energy

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Xuelong; Fei, Zejie; Xiao, Jun; Lu, Di; Hutton, Roger [The Key Lab of Applied Ion Beam Physics, Ministry of Education (China); Shanghai EBIT Laboratory, Modern Physics Institute, Fudan University, Shanghai (China); Zou, Yaming, E-mail: zouym@fudan.edu.cn [The Key Lab of Applied Ion Beam Physics, Ministry of Education (China); Shanghai EBIT Laboratory, Modern Physics Institute, Fudan University, Shanghai (China)

    2013-08-21

    An electron beam ion trap (EBIT) is a powerful machine for disentangling studies of atomic processes in plasmas. To assist studies on edge plasma spectroscopic diagnostics, a very low energy EBIT, SH-PermEBIT, has been set up at the Shanghai EBIT lab. Large amounts of simulation works were done to study the factors which hinder the EBIT from operation at very low electron beam energies. Under the guide line of the simulation results, we finally managed to successfully reach 60 eV for the lower end of the electron beam energy with a beam transmission above 57%. In this presentation, simulation studies of the space charge effect, which is one of the most important causes of beam loss, was made based on Tricomp (Field precision)

  2. Operational Performance of the LHC Proton Beams with the SPS Low Transition Energy Optics

    CERN Document Server

    Papaphilippou, Y; Argyropoulos, T; Bartmann, W; Bartosik, H; Bohl, T; Bracco, C; Cettour-Cave, S; Cornelis, K; Drosdal, L; Esteban Muller, J; Goddard, B; Guerrero, A; H¨ofle, W; Kain, V; Rumolo, G; Salvant, B; Shaposhnikova, E; Timko, H; Valuch, D; Vanbavinckhove, G; Wenninger, J; Gianfelice-Wendt, E

    2013-01-01

    An optics in the SPS with lower integer tunes (20 versus 26) was proposed and introduced in machine studies since 2010, as a measure for increasing transverse and longitudinal instability thresholds, especially at low energy, for the LHC proton beams. After two years of machine studies and careful optimisation, the new Q20 optics became operational in September 2012 and steadily delivered beam to the LHC until the end of the run. This paper reviews the operational performance of the Q20 optics with respect to transverse and longitudinal beam characteristics in the SPS, enabling high brightness beams injected into the LHC. Aspects of longitudinal beam stability, transmission, high-energy orbit control and beam transfer are discussed.

  3. Correction of beam-beam effects in luminosity measurement at ILC

    CERN Document Server

    Lukic, S

    2015-01-01

    Three methods for handling beam-beam effects in luminosity measurement at ILC are tested and evaluated in this work. The first method represents an optimization of the LEPtype asymmetric selection cuts that reduce the counting biases. The second method uses the experimentally reconstructed shape of the √ s ′ spectrum to determine the Beamstrahlung component of the bias. The last, recently proposed, collision-frame method relies on the reconstruction of the collision-frame velocity to define the selection function in the collision frame both in experiment and in theory. Thus the luminosity expression is insensitive to the difference between the CM frame of the collision and the lab frame. The collision-frame method is independent of the knowledge of the beam parameters, and it allows an accurate reconstruction of the luminosity spectrum above 80% of the nominal CM energy. However, it gives no precise infromation about luminosity below 80% of the nominal CM energy. The compatibility of diverse selection cut...

  4. Numerical studies on alpha production from high energy proton beam interaction with Boron

    Science.gov (United States)

    Moustaizis, S. D.; Lalousis, P.; Hora, H.; Korn, G.

    2017-05-01

    Numerical investigations on high energy proton beam interaction with high density Boron plasma allows to simulate conditions concerning the alpha production from recent experimental measurements . The experiments measure the alpha production due to p11B nuclear fusion reactions when a laser-driven high energy proton beam interacts with Boron plasma produced by laser beam interaction with solid Boron. The alpha production and consequently the efficiency of the process depends on the initial proton beam energy, proton beam density, the Boron plasma density and temperature, and their temporal evolution. The main advantage for the p11B nuclear fusion reaction is the production of three alphas with total energy of 8.9 MeV, which could enhance the alpha heating effect and improve the alpha production. This particular effect is termed in the international literature as the alpha avalanche effect. Numerical results using a multi-fluid, global particle and energy balance, code shows the alpha production efficiency as a function of the initial energy of the proton beam, the Boron plasma density, the initial Boron plasma temperature and the temporal evolution of the plasma parameters. The simulations enable us to determine the interaction conditions (proton beam - B plasma) for which the alpha heating effect becomes important.

  5. A layer correlation technique for pion energy calibration at the 2004 ATLAS Combined Beam Test

    Science.gov (United States)

    Abat, E.; Abdallah, J. M.; Addy, T. N.; Adragna, P.; Aharrouche, M.; Ahmad, A.; Akesson, T. P. A.; Aleksa, M.; Alexa, C.; Anderson, K.; Andreazza, A.; Anghinolfi, F.; Antonaki, A.; Arabidze, G.; Arik, E.; Atkinson, T.; Baines, J.; Baker, O. K.; Banfi, D.; Baron, S.; Barr, A. J.; Beccherle, R.; Beck, H. P.; Belhorma, B.; Bell, P. J.; Benchekroun, D.; Benjamin, D. P.; Benslama, K.; Bergeaas Kuutmann, E.; Bernabeu, J.; Bertelsen, H.; Binet, S.; Biscarat, C.; Boldea, V.; Bondarenko, V. G.; Boonekamp, M.; Bosman, M.; Bourdarios, C.; Broklova, Z.; Burckhart Chromek, D.; Bychkov, V.; Callahan, J.; Calvet, D.; Canneri, M.; Capeáns Garrido, M.; Caprini, M.; Cardiel Sas, L.; Carli, T.; Carminati, L.; Carvalho, J.; Cascella, M.; Castillo, M. V.; Catinaccio, A.; Cauz, D.; Cavalli, D.; Cavalli Sforza, M.; Cavasinni, V.; Cetin, S. A.; Chen, H.; Cherkaoui, R.; Chevalier, L.; Chevallier, F.; Chouridou, S.; Ciobotaru, M.; Citterio, M.; Clark, A.; Cleland, B.; Cobal, M.; Cogneras, E.; Conde Muino, P.; Consonni, M.; Constantinescu, S.; Cornelissen, T.; Correard, S.; Corso Radu, A.; Costa, G.; Costa, M. J.; Costanzo, D.; Cuneo, S.; Cwetanski, P.; Da Silva, D.; Dam, M.; Dameri, M.; Danielsson, H. O.; Dannheim, D.; Darbo, G.; Davidek, T.; De, K.; Defay, P. O.; Dekhissi, B.; Del Peso, J.; Del Prete, T.; Delmastro, M.; Derue, F.; Di Ciaccio, L.; Di Girolamo, B.; Dita, S.; Dittus, F.; Djama, F.; Djobava, T.; Dobos, D.; Dobson, M.; Dolgoshein, B. A.; Dotti, A.; Drake, G.; Drasal, Z.; Dressnandt, N.; Driouchi, C.; Drohan, J.; Ebenstein, W. L.; Eerola, P.; Efthymiopoulos, I.; Egorov, K.; Eifert, T. F.; Einsweiler, K.; El Kacimi, M.; Elsing, M.; Emelyanov, D.; Escobar, C.; Etienvre, A. I.; Fabich, A.; Facius, K.; Fakhr-Edine, A. I.; Fanti, M.; Farbin, A.; Farthouat, P.; Fassouliotis, D.; Fayard, L.; Febbraro, R.; Fedin, O. L.; Fenyuk, A.; Fergusson, D.; Ferrari, P.; Ferrari, R.; Ferreira, B. C.; Ferrer, A.; Ferrere, D.; Filippini, G.; Flick, T.; Fournier, D.; Francavilla, P.; Francis, D.; Froeschl, R.; Froidevaux, D.; Fullana, E.; Gadomski, S.; Gagliardi, G.; Gagnon, P.; Gallas, M.; Gallop, B. J.; Gameiro, S.; Gan, K. K.; Garcia, R.; Garcia, C.; Gavrilenko, I. L.; Gemme, C.; Gerlach, P.; Ghodbane, N.; Giakoumopoulou, V.; Giangiobbe, V.; Giokaris, N.; Glonti, G.; Goettfert, T.; Golling, T.; Gollub, N.; Gomes, A.; Gomez, M. D.; Gonzalez-Sevilla, S.; Goodrick, M. J.; Gorfine, G.; Gorini, B.; Goujdami, D.; Grahn, K.-J.; Grenier, P.; Grigalashvili, N.; Grishkevich, Y.; Grosse-Knetter, J.; Gruwe, M.; Guicheney, C.; Gupta, A.; Haeberli, C.; Haertel, R.; Hajduk, Z.; Hakobyan, H.; Hance, M.; Hansen, J. D.; Hansen, P. H.; Hara, K.; Harvey, A., Jr.; Hawkings, R. J.; Heinemann, F. E. W.; Henriques Correia, A.; Henss, T.; Hervas, L.; Higon, E.; Hill, J. C.; Hoffman, J.; Hostachy, J. Y.; Hruska, I.; Hubaut, F.; Huegging, F.; Hulsbergen, W.; Hurwitz, M.; Iconomidou-Fayard, L.; Jansen, E.; Jen-La Plante, I.; Johansson, P. D. C.; Jon-And, K.; Joos, M.; Jorgensen, S.; Joseph, J.; Kaczmarska, A.; Kado, M.; Karyukhin, A.; Kataoka, M.; Kayumov, F.; Kazarov, A.; Keener, P. T.; Kekelidze, G. D.; Kerschen, N.; Kersten, S.; Khomich, A.; Khoriauli, G.; Khramov, E.; Khristachev, A.; Khubua, J.; Kittelmann, T. H.; Klingenberg, R.; Klinkby, E. B.; Kodys, P.; Koffas, T.; Kolos, S.; Konovalov, S. P.; Konstantinidis, N.; Kopikov, S.; Korolkov, I.; Kostyukhin, V.; Kovalenko, S.; Kowalski, T. Z.; Krüger, K.; Kramarenko, V.; Kudin, L. G.; Kulchitsky, Y.; Lacasta, C.; Lafaye, R.; Laforge, B.; Lampl, W.; Lanni, F.; Laplace, S.; Lari, T.; Le Bihan, A.-C.; Lechowski, M.; Ledroit-Guillon, F.; Lehmann, G.; Leitner, R.; Lelas, D.; Lester, C. G.; Liang, Z.; Lichard, P.; Liebig, W.; Lipniacka, A.; Lokajicek, M.; Louchard, L.; Lourerio, K. F.; Lucotte, A.; Luehring, F.; Lund-Jensen, B.; Lundberg, B.; Ma, H.; Mackeprang, R.; Maio, A.; Maleev, V. P.; Malek, F.; Mandelli, L.; Maneira, J.; Mangin-Brinet, M.; Manousakis, A.; Mapelli, L.; Marques, C.; Garcia, S. Marti i.; Martin, F.; Mathes, M.; Mazzanti, M.; McFarlane, K. W.; McPherson, R.; Mchedlidze, G.; Mehlhase, S.; Meirosu, C.; Meng, Z.; Meroni, C.; Mialkovski, V.; Mikulec, B.; Milstead, D.; Minashvili, I.; Mindur, B.; Mitsou, V. A.; Moed, S.; Monnier, E.; Moorhead, G.; Morettini, P.; Morozov, S. V.; Mosidze, M.; Mouraviev, S. V.; Moyse, E. W. J.; Munar, A.; Myagkov, A.; Nadtochi, A. V.; Nakamura, K.; Nechaeva, P.; Negri, A.; Nemecek, S.; Nessi, M.; Nesterov, S. Y.; Newcomer, F. M.; Nikitine, I.; Nikolaev, K.; Nikolic-Audit, I.; Ogren, H.; Oh, S. H.; Oleshko, S. B.; Olszowska, J.; Onofre, A.; Padilla Aranda, C.; Paganis, S.; Pallin, D.; Pantea, D.; Paolone, V.; Parodi, F.; Parsons, J.; Parzhitskiy, S.; Pasqualucci, E.; Passmored, S. M.; Pater, J.; Patrichev, S.; Peez, M.; Perez Reale, V.; Perini, L.; Peshekhonov, V. D.; Petersen, J.; Petersen, T. C.; Petti, R.; Phillips, P. W.; Pina, J.; Pinto, B.; Podlyski, F.; Poggioli, L.; Poppleton, A.; Poveda, J.; Pralavorio, P.; Pribyl, L.; Price, M. J.; Prieur, D.; Puigdengoles, C.; Puzo, P.; RØhne, O.; Ragusa, F.; Rajagopalan, S.; Reeves, K.; Reisinger, I.; Rembser, C.; Bruckman de Renstrom, P. A.; Reznicek, P.; Ridel, M.; Risso, P.; Riu, I.; Robinson, D.; Roda, C.; Roe, S.; Rohne, O.; Romaniouk, A.; Rousseau, D.; Rozanov, A.; Ruiz, A.; Rusakovich, N.; Rust, D.; Ryabov, Y. F.; Ryjov, V.; Salto, O.; Salvachua, B.; Salzburger, A.; Sandaker, H.; Santamarina Rios, C.; Santi, L.; Santoni, C.; Saraiva, J. G.; Sarri, F.; Sauvage, G.; Says, L. P.; Schaefer, M.; Schegelsky, V. A.; Schiavi, C.; Schieck, J.; Schlager, G.; Schlereth, J.; Schmitt, C.; Schultes, J.; Schwemling, P.; Schwindling, J.; Seixas, J. M.; Seliverstov, D. M.; Serin, L.; Sfyrla, A.; Shalanda, N.; Shaw, C.; Shin, T.; Shmeleva, A.; Silva, J.; Simion, S.; Simonyan, M.; Sloper, J. E.; Smirnov, S. Yu; Smirnova, L.; Solans, C.; Solodkov, A.; Solovianov, O.; Soloviev, I.; Sosnovtsev, V. V.; Spanò, F.; Speckmayer, P.; Stancu, S.; Stanek, R.; Starchenko, E.; Straessner, A.; Suchkov, S. I.; Suk, M.; Szczygiel, R.; Tarrade, F.; Tartarelli, F.; Tas, P.; Tayalati, Y.; Tegenfeldt, F.; Teuscher, R.; Thioye, M.; Tikhomirov, V. O.; Timmermans, C. J. W. P.; Tisserant, S.; Toczek, B.; Tremblet, L.; Troncon, C.; Tsiareshka, P.; Tyndel, M.; Karagoez Unel, M.; Unal, G.; Unel, G.; Usai, G.; Van Berg, R.; Valero, A.; Valkar, S.; Valls, J. A.; Vandelli, W.; Vannucci, F.; Vartapetian, A.; Vassilakopoulos, V. I.; Vasilyeva, L.; Vazeille, F.; Vernocchi, F.; Vetter-Cole, Y.; Vichou, I.; Vinogradov, V.; Virzi, J.; Vivarelli, I.; de Vivie, J. B.; Volpi, M.; Anh, T. Vu; Wang, C.; Warren, M.; Weber, J.; Weber, M.; Weidberg, A. R.; Weingarten, J.; Wells, P. S.; Werner, P.; Wheeler, S.; Wiessmann, M.; Wilkens, H.; Williams, H. H.; Wingerter-Seez, I.; Yasu, Y.; Zaitsev, A.; Zenin, A.; Zenis, T.; Zenonos, Z.; Zhang, H.; Zhelezko, A.; Zhou, N.

    2011-06-01

    A new method for calibrating the hadron response of a segmented calorimeter is developed and successfully applied to beam test data. It is based on a principal component analysis of energy deposits in the calorimeter layers, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the calorimeters of the ATLAS experiment were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20GeV and 180GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by between 11% and 25% compared to the resolution at the electromagnetic scale.

  6. Application of digital beam position processor Libera on tune measurement

    International Nuclear Information System (INIS)

    Zhang Chunhui; Sun Baogen; Cao Yong; Lu Ping; Li Jihao

    2006-01-01

    Digital signal processing (DSP) is widely used in the field of beam diagnostics. Especially, DSP achieves very good performance in beam position signal analysis and betatron tune measurement. In Hefei light source, when beam was excited by narrow-band Gaussian white nose, Libera, a digital beam position processor, was used to process the signals from beam position monitor (BPM), which contained betatron oscillation. Fast Fourier transform (FFT) was applied to finding out betatron resonance frequency, from which the decimal part of betatron oscillation tune was calculated. By this means, the measure of horizontal tune was 3.5352 and the measure of vertical tune is 2.6299. (authors)

  7. High energy density in matter produced by heavy ion beams

    International Nuclear Information System (INIS)

    1987-08-01

    This annual report summarizes the results of research carried out in 1986 within the framework of the program 'High Energy Density in Matter Produced by Heavy Ion Beams' which is funded by the Federal Ministry for Research and Technology. Its initial motivation and its ultimate goal is the question whether inertial confinement can be achieved by intense beams of heavy ions. (orig./HSI)

  8. Production of simultaneous, variable energy beams from the TRIUMF cyclotron

    International Nuclear Information System (INIS)

    Richardson, J.R.; Blackmore, E.W.; Dutto, G.; Kost, C.J.; Mackenzie, G.H.; Craddock, M.K.

    1975-01-01

    An extracted beam at the design energy of 500 MeV was obtained at TRIUMF in December, 1974. Later, beams of varying energies between 180 and 520 MeV were extracted down beam line 4, and further work resulted in the simultaneous extraction of a 506 MeV beam down beam line 1 and variable energy beams down line 4. In order to reduce initial activation of cyclotron components, time average beams were restricted to 100 nA, but 12 μA in a pulsed beam was very easily obtained at 500 MeV. Without optimization of the injection conditions and without use of the harmonic trim coils, an energy spread (full width) of 2.5 to 3.0 MeV was observed. Ordinarily, the macro-duty factor was 100 percent, and the micro-duty factor corresponded to a 5 ns pulse every 44 ns. The transmission to 500 MeV is consistent with the expected loss due to gas stripping. (auth)

  9. Transverse Beam Halo Measurements at High Intensity Neutrino Source (HINS) using Vibrating Wire Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Chung, M.; Hanna, B.; Scarpine, V.; Shiltsev, V.; Steimel, J.; Artinian, S.; Arutunian, S.

    2015-02-26

    The measurement and control of beam halos will be critical for the applications of future high-intensity hadron linacs. In particular, beam profile monitors require a very high dynamic range when used for the transverse beam halo measurements. In this study, the Vibrating Wire Monitor (VWM) with aperture 60 mm was installed at the High Intensity Neutrino Source (HINS) front-end to measure the transverse beam halo. A vibrating wire is excited at its resonance frequency with the help of a magnetic feedback loop, and the vibrating and sensitive wires are connected through a balanced arm. The sensitive wire is moved into the beam halo region by a stepper motor controlled translational stage. We study the feasibility of the vibrating wire for the transverse beam halo measurements in the low-energy front-end of the proton linac.

  10. Polystyrene calorimeter for electron beam dose measurements

    DEFF Research Database (Denmark)

    Miller, A.

    1995-01-01

    Calorimeters from polystrene have been constructed for dose measurement at 4-10 MeV electron accelerators. These calorimeters have been used successfully for a few years, and polystyrene calorimeters for use at energies down to 1 MeV and being tested. Advantage of polystyrene as the absorbing...

  11. Substrate heating measurements in pulsed ion beam film deposition

    Energy Technology Data Exchange (ETDEWEB)

    Olson, J.C.; Davis, H.A.; Rej, D.J.; Waganaar, W.J. [Los Alamos National Lab., NM (United States); Tallant, D.R. [Cornell Univ., Ithaca, NY (United States). Materials Science and Engineering Dept.; Thompson, M.O. [Sandia National Labs., Albuquerque, NM (United States)

    1995-05-01

    Diamond-like Carbon (DLC) films have been deposited at Los Alamos National Laboratory by pulsed ion beam ablation of graphite targets. The targets were illuminated by an intense beam of hydrogen, carbon, and oxygen ions at a fluence of 15-45 J/cm{sup 2}. Ion energies were on the order of 350 keV, with beam current rising to 35 kA over a 400 ns ion current pulse. Raman spectra of the deposited films indicate an increasing ratio of sp{sup 3} to sp{sup 2} bonding as the substrate is moved further away from the target and further off the target normal. Using a thin film platinum resistor at varying positions, we have measured the heating of the substrate surface due to the kinetic energy and heat of condensation of the ablated material. This information is used to determine if substrate heating is responsible for the lack of DLC in positions close to the target and near the target normal. Latest data and analysis will be presented.

  12. Reduction of energy sweep of the ETA-II beam

    International Nuclear Information System (INIS)

    Nexsen, W.E.; Allen, S.L.; Chambers, F.W.; Jong, R.A.; Paul, A.C.; Sampayan, S.E.; Turner, W.C.

    1991-05-01

    The ETA-2 electron beam will be used to drive a high power microwave frequency FEL for plasma heating experiments. For maximum FEL output power the beam energy at the entrance to the wiggler should be within ±1% of the wiggler resonance value. In initial operations the ETA-2 beam energy stayed within this range for a maximum time of less than 13 ns, Much of the energy variation was due to the design of the pulsed power feeds to the of the pulsed power feeds to the accelerator induction cells. A new multicable pulsed power feed design was tested in a shortened version of ETA-2 where it extended the time during which the beam energy stayed within the ±1% limits to greater than 40 ns. These design changes are now being incorporated into the full accelerator. 9 refs., 4 figs

  13. Comparison of beam simulations with measurements for a 1.25-MeV, CW RFQ

    Energy Technology Data Exchange (ETDEWEB)

    Smith, H.V. Jr.; Bolme, G.O.; Sherman, J.D.; Stevens, R.R. Jr.; Young, L.M.; Zaugg, T.J.

    1998-12-31

    The Low-Energy Demonstration Accelerator (LEDA) injector is tested using the Chalk River Injector Test Stand (CRITS) radio-frequency quadrupole (RFQ) as a diagnostic instrument. Fifty-keV, dc proton beams are injected into the 1.25-MeV, CW RFQ and transported to a beamstop. Computer-simulation-code predictions of the expected beam performance are compared with the measured beam currents and beam profiles. Good agreement is obtained between the measurements and the simulations at the 75-mA design RFQ output current.

  14. Accurate measurement of the electron beam polarization in JLab Hall A using Compton polarimetry

    International Nuclear Information System (INIS)

    Escoffier, S.; Bertin, P.Y.; Brossard, M.; Burtin, E.; Cavata, C.; Colombel, N.; Jager, C.W. de; Delbart, A.; Lhuillier, D.; Marie, F.; Mitchell, J.; Neyret, D.; Pussieux, T.

    2005-01-01

    A major advance in accurate electron beam polarization measurement has been achieved at Jlab Hall A with a Compton polarimeter based on a Fabry-Perot cavity photon beam amplifier. At an electron energy of 4.6GeV and a beam current of 40μA, a total relative uncertainty of 1.5% is typically achieved within 40min of data taking. Under the same conditions monitoring of the polarization is accurate at a level of 1%. These unprecedented results make Compton polarimetry an essential tool for modern parity-violation experiments, which require very accurate electron beam polarization measurements

  15. Digital DC beam current measurement on SSRF storage ring

    International Nuclear Information System (INIS)

    Xiong Liang; Yin Chongxian; Liu Ming; Chen Jianfeng

    2011-01-01

    Both DC current transformer (DCCT) and integrating current transformer (ICT) can be used in DC beam current measurement. The ICT has strong capability of resisting electromagnetic interference, but its measurement accuracy cannot satisfy the DC beam current measurement requirement when using traditional high speed A/D. With high resolution A/D and equivalent sampling system, DC beam current measuring system based on ICT can reach high accuracy compared with DCCT system. In this paper, the ICT-based DC beam current measurement, equivalent sampling method and testing results at Shanghai Synchrotron Radiation Facility(SSRF) is described. (authors)

  16. Longitudinal impedance of a step-in for a round beam at arbitrary beam energy

    Energy Technology Data Exchange (ETDEWEB)

    Al-Khateeb, A.M., E-mail: a.alkhateeb@gsi.d [FAIR-Accelerator Theory Group, GSI Darmstadt, Planckstr. 1, D-64291 Darmstadt (Germany); Boine-Frankenheim, O.; Plotnikov, A. [FAIR-Accelerator Theory Group, GSI Darmstadt, Planckstr. 1, D-64291 Darmstadt (Germany); Shim, S.Y. [FAIR Division, Magnettechnik/Kryotechnik, GSI Darmstadt, Planckstr. 1, D-64291 Darmstadt (Germany); Haenichen, L. [Technische Universitaet Darmstadt, Institut fuer Theorie elektromagnetischer Felder, TEMF, Schlossgartenstr. 8, D-64289 Darmstadt (Germany)

    2011-01-21

    Contribution of step-in geometric discontinuity to the longitudinal coupling impedance has been obtained analytically using exact field matching. We assumed a perfectly conducting beam-pipe wall of two different radii connected coaxially at z=0 so that the contribution to the longitudinal coupling impedance is purely due to the beam-pipe geometric discontinuity. We also obtained the longitudinal loss factor for a Gaussian beam as a function of beam energy and bunch length. Results have been analyzed numerically for some representative parameters close to real machine parameters. Analytical results have also been compared with numerical simulation from CST at relativistic beam energies. We found a very good agreement between theory and simulation.

  17. Low-energy beam transport using space-charge lenses

    International Nuclear Information System (INIS)

    Meusel, O.; Bechtold, A.; Pozimski, J.; Ratzinger, U.; Schempp, A.; Klein, H.

    2005-01-01

    Space-charge lenses (SCL) of the Gabor type provide strong cylinder symmetric focusing for low-energy ion beams using a confined nonneutral plasma. They need modest magnetic and electrostatic field strength and provide a short installation length when compared to conventional LEBT-lenses like quadrupoles and magnetic solenoids. The density distribution of the enclosed space charge within the Gabor lens is given by the confinement in transverse and longitudinal directions. In the case of a positive ion beam, the space charge of the confined electron cloud may cause an overcompensation of the ion beam space-charge force and consequently focuses the beam. To investigate the capabilities of an SCL double-lens system for ion beam into an RFQ, a test injector was installed at IAP and put into operation successfully. Furthermore, to study the focusing capabilities of this lens at beam energies up to 500 keV, a high-field Gabor lens was built and installed downstream of the RFQ. Experimental results of the beam injection into the RFQ are presented as well as those of these first bunched beam-focusing tests with the 110 A keV He + beam

  18. Diffraction measurements using the LHC Beam Loss Monitoring System

    Science.gov (United States)

    Kalliokoski, Matti

    2017-03-01

    The Beam Loss Monitoring (BLM) system of the Large Hadron Collider protects the machine from beam induced damage by measuring the absorbed dose rates of beam losses, and by triggering beam dump if the rates increase above the allowed threshold limits. Although the detection time scales are optimized for multi-turn losses, information on fast losses can be recovered from the loss data. In this paper, methods in using the BLM system in diffraction studies are discussed.

  19. AIP Diffraction measurements using the LHC Beam Loss Monitoring System

    CERN Document Server

    Kalliokoski, Matti

    2017-01-01

    The Beam Loss Monitoring (BLM) system of the Large Hadron Collider protects the machine from beam induced damage by measuring the absorbed dose rates of beam losses, and by triggering beam dump if the rates increase above the allowed threshold limits. Although the detection time scales are optimized for multi-turn losses, information on fast losses can be recovered from the loss data. In this paper, methods in using the BLM system in di ff raction studies are discussed.

  20. Treatment of basal cell epithelioma with high energy electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Y. (Hyogo-ken Cancer Center, Kobe (Japan)); Kumano, M.; Kumano, K.

    1981-11-01

    Thirty patients with basal cell epithelioma received high energy electron beam therapy. They were irradiated with a dose ranging from 4,800 rad (24 fractions, 35 days) to 12,000 rad (40 fractions, 57 days). Tumors disappeared in all cases. These were no disease-related deaths; in one patient there was recurrence after 2 years. We conclude that radiotherapy with high energy electron beam is very effective in the treatment of basal cell epithelioma.

  1. Intermediate-energy neutron beams from reactors for NCT

    International Nuclear Information System (INIS)

    Brugger, R.M.; Less, T.J.; Passmore, G.G.

    1986-01-01

    This paper discusses ways that a beam of intermediate-energy neutrons might be extracted from a nuclear reactor. The challenge is to suppress the fast-neutron component and the gamma-ray component of the flux while leaving enough of the intermediate-energy neutrons in the beam to be able to perform neutron capture therapy in less than an hour exposure time. Moderators, filters, and reflectors are considered. 11 references, 7 figures, 3 tables

  2. Measuring beam losses in the THI project

    International Nuclear Information System (INIS)

    David, L.; Duneau, P.; Lecorche, E.; Lermine, P.; Lemaitre, E.; Ulrich, M.

    1997-01-01

    The goal of the THI project (High Intensity Transport) is to upgrade the GANIL facilities by increasing the beam by a factor of 15, at least for light ions. This higher intensity is required by the radioactive beam facility SPIRAL starting in September 1997, to generate the new nuclear species in the solid target-source (ISOL method). For the control system, the most important issues are now to tune the accelerators while minimizing the beam losses at each stage of acceleration and when not possible, to have a fast beam loss detection signal. This system is composed of probes which deliver a signal to stop the beam when there's too much intensity lost and when not, a logarithmic value of the beam intensity. These probes are linked to a front end VME crate on the network, and in the control room, on the workstations, a graphical user interface program displays the beam variations using logarithmic scales. This program is also used to center the beam while injecting in or ejecting from the main cyclotrons by tuning the steerers, the magnetic elements inside, and the electrostatic deflector to be able to separate and extract the last beam turn. (author)

  3. Audit of high energy therapy beams in hospital oncology departments by the National Radiation Laboratory

    International Nuclear Information System (INIS)

    Smyth, V.G.

    1994-02-01

    In 1993 the output of every high energy radiotherapy beam used clinically in New Zealand was measured by National Radiation Laboratory (NRL) staff using independent dosimetry equipment. The purpose of this was to audit the dosimetry that is used by hospital physicists for the basis of patient treatments, and to uncover any errors that may be clinically significant. This report analyses the uncertainties involved in comparing the NRL and hospital measurements, and presents the results of the 1993 audit. The overall uncertainty turns out to be about 1.5%. The results for linear accelerator photon beams are consistent with a purely random variation within this uncertainty. Electron beams show some small errors beyond the expected uncertainty. Gamma beams have the potential to be the most accurately measured, but in practice are less accurately measured than linear accelerator beams. None of the disagreements indicated an error of clinical significance. 8 refs., 3 figs., 2 tabs

  4. Experimental investigation of fatigue in a cantilever energy harvesting beam

    Science.gov (United States)

    Avvari, Panduranga Vittal; Yang, Yaowen; Liu, Peiwen; Soh, Chee Kiong

    2015-03-01

    Over the last decade, cantilever energy harvesters gained immense popularity owing to the simplicity of the design and piezoelectric energy harvesting (PEH) using the cantilever design has undergone considerable evolution. The major drawback of a vibrating cantilever beam is its vulnerability to fatigue over a period of time. This article brings forth an experimental investigation into the phenomenon of fatigue of a PEH cantilever beam. As there has been very little literature reported in this area, an effort has been made to scrutinize the damage due to fatigue in a linear vibrating cantilever PEH beam consisting of an aluminum substrate with a piezoelectric macro-fiber composite (MFC) patch attached near the root of the beam and a tip mass attached to the beam. The beam was subjected to transverse vibrations and the behavior of the open circuit voltage was recorded with passing time. Moreover, electro-mechanical admittance readings were obtained periodically using the same MFC patch as a Structural health monitoring (SHM) sensor to assess the health of the PEH beam. The results show that with passing time the PEH beam underwent fatigue in both the substrate and MFC, which is observed in a complimentary trend in the voltage and admittance readings. The claim is further supported using the variation of root mean square deviation (RMSD) of the real part of admittance (conductance) readings. Thus, this study concludes that the fatigue issue should be addressed in the design of PEH for long term vibration energy harvesting.

  5. DIAGNOSTICS FOR ION BEAM DRIVEN HIGH ENERGY DENSITY PHYSICS EXPERIMENTS

    International Nuclear Information System (INIS)

    Bieniosek, F.M.; Henestroza, E.; Lidia, S.; Ni, P.A.

    2010-01-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30-mA K + beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multi-channel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (VISAR), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  6. Electron Beam Energy Compensation by Controlling RF Pulse Shape

    CERN Document Server

    Kii, T; Kusukame, K; Masuda, K; Nakai, Y; Ohgaki, H; Yamazaki, T; Yoshikawa, K; Zen, H

    2005-01-01

    We have studied on improvement of electron beam macropulse properties from a thermionic RF gun. Though a thermionic RF gun has many salient features, there is a serious problem that back-bombardment effect worsens quality of the beam. To reduce beam energy degradation by this effect, we tried to feed non-flat RF power into the gun. As a result, we successfully obtained about 1.5 times longer macropulse and two times larger total charge per macropulse. On the other hand, we calculated transient evolution of RF power considering non-constant beam loading. The beam loading is evaluated from time evolution of cathode temperature, by use of one dimensional heat conduction model and electron trajectories' calculations by a particle simulation code. Then we found good agreement between the experimental and calculation results. Furthermore, with the same way, we studied the electron beam output dependence on the cathode radius.

  7. Diagnostics for ion beam driven high energy density physics experiments.

    Science.gov (United States)

    Bieniosek, F M; Henestroza, E; Lidia, S; Ni, P A

    2010-10-01

    Intense beams of heavy ions are capable of heating volumetric samples of matter to high energy density. Experiments are performed on the resulting warm dense matter (WDM) at the NDCX-I ion beam accelerator. The 0.3 MeV, 30 mA K(+) beam from NDCX-I heats foil targets by combined longitudinal and transverse neutralized drift compression of the ion beam. Both the compressed and uncompressed parts of the NDCX-I beam heat targets. The exotic state of matter (WDM) in these experiments requires specialized diagnostic techniques. We have developed a target chamber and fielded target diagnostics including a fast multichannel optical pyrometer, optical streak camera, laser Doppler-shift interferometer (Velocity Interferometer System for Any Reflector), beam transmission diagnostics, and high-speed gated cameras. We also present plans and opportunities for diagnostic development and a new target chamber for NDCX-II.

  8. The quality of high-energy X-ray beams

    International Nuclear Information System (INIS)

    LaRiviere, P.D.

    1989-01-01

    Supplement 17 of the British Journal of Radiology is a survey of central-axis depth doses for radiotherapy machines, patterned largely on BJR Supplement 11 (1972). Inspection of high-energy X-ray depth doses for a 10 x 10 cm field at an SSD of 100 cm disclosed large differences between the two sets of data, especially for qualities above 8 MV, e.g. a depth dose of 80% at 10 cm is rated at about 19 MV according to BJR Supplement 11, and 23 MV according to BJR Supplement 17. It was found that Supplement 17 depth-dose data above 8 MV were erratic, but Supplement 11 data could be represented by an analytical expression, providing a unique means of assigning MV quality. It was also found that dose-weighted average energy of the filtered beam plotted smoothly against depth dose. For dosimetric purposes, it is suggested that this parameter be used as a true measure of beam quality, removing discrepancies introduced by the use of nominal MV for this purpose. (author)

  9. Electron Beam Size Measurements in a Cooling Solenoid

    CERN Document Server

    Kroc, Thomas K; Burov, Alexey; Seletsky, Sergey; Shemyakin, Alexander V

    2005-01-01

    The Fermilab Electron Cooling Project requires a straight trajectory and constant beam size to provide effective cooling of the antiprotons in the Recycler. A measurement system was developed using movable appertures and steering bumps to measure the beam size in a 20 m long, nearly continuous, solenoid. This paper discusses the required beam parameters, the implimentation of the measurement system and results for our application.

  10. Neutral beam power measurements inside the ASDEX torus

    International Nuclear Information System (INIS)

    Zengliang, Y.; Staebler, A.; Vollmer, O.

    1982-11-01

    Neutral beam power measurements inside the ASDEX torus are done with a retractable calorimeter which is only radiation cooled. The calorimeter plate made from Molybdenum is subdivided into nine segments whose increase in energy content due to a shot yields the absorbed beam power. Different models for the backward extrapolation of the measured temperature curves are examined for a series of low energy shots with the result that pure radiation cooling is a valid assumption. Furthermore, a temperature correction to the measured power is derived from these experiments. The evaluation of the shots onto this calorimeter is done by a computer program. The application of this program to a few full power shots shows that a neutral power up to 3.2 MW has been injected into the ASDEX vessel by the two injectors with an overall efficiency of up to 40%. Reionization losses due to the ASDEX stray field are less than 10%; they do not show any dependence upon the pulse length for shots up to 200 ms. (orig.)

  11. LHC Beam Instrumentation: Beam Position and Intensity Measurements (1/3)

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The LHC is equipped with a full suite of sophisticated beam instrumentation which has been essential for rapid commissioning, the safe increase in total stored beam power and the understanding of machine optics and accelerator physics phenomena. These lectures will introduce these systems and comment on their contributions to the various stages of beam operation. They will include details on: the beam position system and its use for real-time global orbit feedback; the beam loss system and its role in machine protection; total and bunch by bunch intensity measurements; tune measurement and feedback; diagnostics for transverse beam size measurements, abort gap monitoring and longitudinal density measurements. Issues and problems encountered along the way will also be discussed together with the prospect for future upgrades.

  12. LHC Beam Instrumentation: Beam Loss and Tune Measurements (3/3)

    CERN Multimedia

    CERN. Geneva

    2014-01-01

    The LHC is equipped with a full suite of sophisticated beam instrumentation which has been essential for rapid commissioning, the safe increase in total stored beam power and the understanding of machine optics and accelerator physics phenomena. These lectures will introduce these systems and comment on their contributions to the various stages of beam operation. They will include details on: the beam position system and its use for real-time global orbit feedback; the beam loss system and its role in machine protection; total and bunch by bunch intensity measurements; tune measurement and feedback; diagnostics for transverse beam size measurements, abort gap monitoring and longitudinal density measurements. Issues and problems encountered along the way will also be discussed together with the prospect for future upgrades.

  13. Effects of ambient gas in beam drift space on performance of high brightness and low energy ion beam

    International Nuclear Information System (INIS)

    Yoshikawa, T.; Nakamura, S.; Ueda, Y.; Nishikawa, M.; Goto, S.

    1995-01-01

    Effects of the ambient gas in the ion drift space on the transport property of the low energy (155 eV) and high brightness beam are studied experimentally. A bucket ion source with single-aperture triode extraction is used. Beam characteristics such as the divergence angle and the current density are improved by the increase in the ambient gas pressure in the high brightness beam (high deceleration voltage, -2000 V), but not in the low brightness beam (low deceleration voltage, -600 V). The beam spreading due to the space charge of the ion beam is seen at the low ambient gas pressure when the central current density, which is measured at 35 cm downstream side from the electrode system, exceeds 5 μA/cm 2 . The electron density in the ion-beam plasma increases with the ambient gas pressure, but the space charge is not sufficiently neutralized by the electrons produced by the ambient gas atom ionization. copyright 1995 American Institute of Physics

  14. Beam-to-Column Connections with Demountable Energy Dissipative Plates

    Directory of Open Access Journals (Sweden)

    Vasile-Mircea Venghiac

    2018-03-01

    Full Text Available The behavior of steel structures subjected to seismic actions depends directly on the connections behavior. There are two current tendencies for ensuring the structural ductility: allowing the formation of plastic hinges in the beams by using reduced beam sections or reduced web sections or by ensuring the plastic hinge formation in the connection by using dissipative elements. This paper presents a new perspective regarding the energy dissipation mechanism formation within the beam-to-column connection. The design of connections capable of dissipating large amounts of energy, with an acceptable strength and ductile behavior is a real challenge for engineers. Sustainability is a big advantage for these connections. Another big advantage is the possibility of restoring the functionality of the damaged construction in a short time interval and with reduced costs. The introduction of connections with demountable energy dissipative plates can be a step forward in designing new beam-to-column connections for steel structures.

  15. Crystal Collimation with Lead Ion Beams at Injection Energy in the LHC

    CERN Document Server

    Rossi, Roberto; Andreassen, Arvid; Butcher, Mark; Dionisio Barreto, Cristovao Andre; Masi, Alessandro; Mirarchi, Daniele; Montesano, Simone; Lamas Garcia, Inigo; Redaelli, Stefano; Scandale, Walter; Serrano Galvez, Pablo; Rijllart, Adriaan; Valentino, Gianluca; Galluccio, Francesca; CERN. Geneva. ATS Department

    2015-01-01

    During this MD, performed on December 2nd 2015, bent silicon crystals were tested with ion beams for a possible usage of crystal-assisted collimation. Tests were performed at injection energy, using both horizontal and vertical crystals. Ion channeling was observed for the first time with LHC beams at the record energy of 450 GeV and the channeled beams were probed with scans performed with secondary collimators. Measurements of cleaning efficiency of a crystal-based collimation system were also performed.

  16. Experimental device for measurement of dielectronic recombination cross section of C3+: method of confluent beam method

    International Nuclear Information System (INIS)

    Menier, A.

    1985-09-01

    Description of an instrumental device allowing dielectronic recombination cross section measurement is presented. Recombination of C 3+ for high quantum number is studied. This device, using the confluent beam method, entailed the development of an electron gun producing weakly divergent beam. A detector of highly excited ion allowing a quick and accurate measurement of ion beam energy is described in detail. Beam-residual gas interaction mechanisms are studied and instrumental incertitudes are calculated [fr

  17. Design study of low-energy beam transport for multi-charge beams at RAON

    Science.gov (United States)

    Bahng, Jungbae; Qiang, Ji; Kim, Eun-San

    2015-12-01

    The Rare isotope Accelerator Of Newness (RAON) at the Rare Isotope Science Project (RISP) is being designed to simultaneously accelerate beams with multiple charge states. It includes a driver superconducting (SC) linac for producing 200 MeV/u and 400 kW continuous wave (CW) heavy ion beams from protons to uranium. The RAON consists of a few electron cyclotron resonance ion sources, a low-energy beam transport (LEBT) system, a CW 81.25 MHz, 500 keV/u radio frequency quadrupole (RFQ) accelerator, a medium-energy beam transport system, the SC linac, and a charge-stripper system. The LEBT system for the RISP accelerator facility consists of a high-voltage platform, two 90° dipoles, a multi-harmonic buncher (MHB), solenoids, electrostatic quadrupoles, a velocity equalizer, and a diagnostic system. The ECR ion sources are located on a high-voltage platform to reach an initial beam energy of 10 keV/u. After extraction, the ion beam is transported through the LEBT system to the RFQ accelerator. The generated charge states are selected by an achromatic bending system and then bunched by the MHB in the LEBT system. The MHB is used to achieve a small longitudinal emittance in the RFQ by generating a sawtooth wave with three harmonics. In this paper, we present the results and issues of the beam dynamics of the LEBT system.

  18. Turbulent Kinetic Energy (TKE) Budgets Using 5-beam Doppler Profilers

    Science.gov (United States)

    Guerra, M. A.; Thomson, J. M.

    2016-12-01

    Field observations of turbulence parameters are important for the development of hydrodynamic models, understanding contaminant mixing, and predicting sediment transport. The turbulent kinetic energy (TKE) budget quantifies where turbulence is being produced, dissipated or transported at a specific site. The Nortek Signature 5-beam AD2CP was used to measure velocities at high sampling rates (up to 8 Hz) at Admiralty Inlet and Rich Passage in Puget Sound, WA, USA. Raw along-beam velocity data is quality controlled and is used to estimate TKE spectra, spatial structure functions, and Reynolds stress tensors. Exceptionally low Doppler noise in the data enables clear observations of the inertial sub-range of isotropic turbulence in both the frequency TKE spectra and the spatial structure functions. From these, TKE dissipation rates are estimated following Kolmogorov's theory of turbulence. The TKE production rates are estimated using Reynolds stress tensors together with the vertical shear in the mean flow. The Reynolds stress tensors are estimated following the methodology of Dewey and Stinger (2007), which is significantly improved by inclusion of the 5th beam (as opposed to the conventional 4). These turbulence parameters are used to study the TKE budget along the water column at the two sites. Ebb and flood production and dissipation rates are compared through the water column at both sites. At Admiralty Inlet, dissipation exceeds production during ebb while the opposite occurs during flood because the proximity to a lateral headland. At Rich Passage, production exceeds dissipation through the water column for all tidal conditions due to a vertical sill in the vicinity of the measurement site.

  19. Time-resolved energy spectrum of a pseudospark-produced high-brightness electron beam

    International Nuclear Information System (INIS)

    Myers, T.J.; Ding, B.N.; Rhee, M.J.

    1992-01-01

    The pseudospark, a fast low-pressure gas discharge between a hollow cathode and a planar anode, is found to be an interesting high-brightness electron beam source. Typically, all electron beam produced in the pseudospark has the peak current of ∼1 kA, pulse duration of ∼50 ns, and effective emittance of ∼100 mm-mrad. The energy information of this electron beam, however, is least understood due to the difficulty of measuring a high-current-density beam that is partially space-charge neutralized by the background ions produced in the gas. In this paper, an experimental study of the time-resolved energy spectrum is presented. The pseudospark produced electron beam is injected into a vacuum through a small pinhole so that the electrons without background ions follow single particle motion; the beam is sent through a negative biased electrode and the only portion of beam whose energy is greater than the bias voltage can pass through the electrode and the current is measured by a Faraday cup. The Faraday cup signals with various bias voltage are recorded in a digital oscilloscope. The recorded waveforms are then numerically analyzed to construct a time-resolved energy spectrum. Preliminary results are presented

  20. Measurements on wave propagation characteristics of spiraling electron beams

    Science.gov (United States)

    Singh, A.; Getty, W. D.

    1976-01-01

    Dispersion characteristics of cyclotron-harmonic waves propagating on a neutralized spiraling electron beam immersed in a uniform axial magnetic field are studied experimentally. The experimental setup consisted of a vacuum system, an electron-gun corkscrew assembly which produces a 110-eV beam with the desired delta-function velocity distribution, a measurement region where a microwave signal is injected onto the beam to measure wavelengths, and a velocity analyzer for measuring the axial electron velocity. Results of wavelength measurements made at beam currents of 0.15, 1.0, and 2.0 mA are compared with calculated values, and undesirable effects produced by increasing the beam current are discussed. It is concluded that a suitable electron beam for studies of cyclotron-harmonic waves can be generated by the corkscrew device.

  1. Measurement of neutron yield by 62 MeV proton beam on a thick beryllium target

    Energy Technology Data Exchange (ETDEWEB)

    Osipenko, M., E-mail: osipenko@ge.infn.it [INFN, sezione di Genova, 16146 Genova (Italy); Ripani, M. [INFN, sezione di Genova, 16146 Genova (Italy); Alba, R. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Ricco, G. [INFN, sezione di Genova, 16146 Genova (Italy); Schillaci, M. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Barbagallo, M. [INFN, sezione di Bari, 70126 Bari (Italy); Boccaccio, P. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Celentano, A. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy); Colonna, N. [INFN, sezione di Bari, 70126 Bari (Italy); Cosentino, L.; Del Zoppo, A.; Di Pietro, A. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Esposito, J. [INFN, Laboratori Nazionali di Legnaro, 35020 Legnaro (Italy); Figuera, P.; Finocchiaro, P. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Kostyukov, A. [Moscow State University, Moscow 119992 (Russian Federation); Maiolino, C.; Santonocito, D.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, 95123 Catania (Italy); Viberti, C.M. [Dipartimento di Fisica dell' Università di Genova, 16146 Genova (Italy)

    2013-09-21

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0° to 150° and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their time of flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a {sup 3}He detector was used. The obtained data are in good agreement with previous measurements at 0° using 66 MeV proton beam, covering neutron energies >10MeV, as well as with measurements at few selected angles using protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60–70 MeV beam energy range. A comparison of measured yields to MCNP, FLUKA and Geant4 Monte Carlo simulations was performed.

  2. Measurement of neutron yield by 62 MeV proton beam on a thick beryllium target

    Science.gov (United States)

    Osipenko, M.; Ripani, M.; Alba, R.; Ricco, G.; Schillaci, M.; Barbagallo, M.; Boccaccio, P.; Celentano, A.; Colonna, N.; Cosentino, L.; Del Zoppo, A.; Di Pietro, A.; Esposito, J.; Figuera, P.; Finocchiaro, P.; Kostyukov, A.; Maiolino, C.; Santonocito, D.; Scuderi, V.; Viberti, C. M.

    2013-09-01

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0° to 150° and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their time of flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a 3He detector was used. The obtained data are in good agreement with previous measurements at 0° using 66 MeV proton beam, covering neutron energies >10 MeV, as well as with measurements at few selected angles using protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60-70 MeV beam energy range. A comparison of measured yields to MCNP, FLUKA and Geant4 Monte Carlo simulations was performed.

  3. Measurement of neutron yield by 62 MeV proton beam on a thick beryllium target

    International Nuclear Information System (INIS)

    Osipenko, M.; Ripani, M.; Alba, R.; Ricco, G.; Schillaci, M.; Barbagallo, M.; Boccaccio, P.; Celentano, A.; Colonna, N.; Cosentino, L.; Del Zoppo, A.; Di Pietro, A.; Esposito, J.; Figuera, P.; Finocchiaro, P.; Kostyukov, A.; Maiolino, C.; Santonocito, D.; Scuderi, V.; Viberti, C.M.

    2013-01-01

    The design of a low-power prototype of neutron amplifier recently proposed within the INFN-E project indicated the need for more accurate data on the neutron yield produced by a proton beam with energy of about 70 MeV impinging on a thick beryllium target. Such measurement was performed at the LNS superconducting cyclotron, covering a wide angular range from 0° to 150° and a complete neutron energy interval from thermal to beam energy. Neutrons with energy above 0.5 MeV were measured by liquid scintillators exploiting their time of flight to determine the kinetic energy. For lower energy neutrons, down to thermal energy, a 3 He detector was used. The obtained data are in good agreement with previous measurements at 0° using 66 MeV proton beam, covering neutron energies >10MeV, as well as with measurements at few selected angles using protons of 46, 55 and 113 MeV energy. The present results extend the neutron yield data in the 60–70 MeV beam energy range. A comparison of measured yields to MCNP, FLUKA and Geant4 Monte Carlo simulations was performed

  4. Reliability analysis of minimum energy on target for laser facilities with more beam lines

    International Nuclear Information System (INIS)

    Chen Guangyu

    2008-01-01

    Shot reliability performance measures of laser facilities with more beam lines pertain to three categories: minimum-energy-on-target, power balance, and shot diagnostics. Accounting for symmetry of NIF beam line design and similarity of subset reliability in a same partition, a fault tree of meeting minimum-energy-on-target for the large laser facility shot of type K and a simplified method are presented, which are used to analyze hypothetic reliability of partition subsets in order to get trends of influences increasing number of beam lines and diverse shot types of large laser facilities on their shot reliability. Finally, it finds that improving component reliability is more crucial for laser facilities with more beam lines in comparison with those with beam lines and functional diversity from design flexibility is greatly helpful for improving shot reliability. (authors)

  5. Measurements of the Argonne Wakefield Accelerator's low charge, 4 MeV RF photocathode witness beam

    International Nuclear Information System (INIS)

    Power, J.

    1998-01-01

    The Argonne Wakefield Accelerator's (AWA) witness RF photocathode gun produced its first electron beam in April of 1996. We have characterized the charge, energy, emittance and bunch length of the witness beam over the last several months. The emittance Was measured by both a quad scan that fitted for space charge using an in house developed Mathematica routine and a pepper pot technique. The bunch length was measured by imaging Cherenkov light from a quartz plate to a Hamamatsu streak camera with 2 psec resolution. A beam energy of 3.9 Mev was measured with a 6 inch round pole spectrometer while a beam charge was measured with both an ICT and a Faraday Cup. Although the gun will normally be run at 100 pC it has produced charges from 10 pC to 4 nc. All results of the measurements to date are presented here

  6. Study of energy dependence of a extrapolation chamber in low energy X-rays beams

    International Nuclear Information System (INIS)

    Bastos, Fernanda M.; Silva, Teogenes A. da

    2014-01-01

    This work was with the main objective to study the energy dependence of extrapolation chamber in low energy X-rays to determine the value of the uncertainty associated with the variation of the incident radiation energy in the measures in which it is used. For studying the dependence of energy, were conducted comparative ionization current measurements between the extrapolation chamber and two ionization chambers: a chamber mammography, RC6M model, Radcal with energy dependence less than 5% and a 2575 model radioprotection chamber NE Technology; both chambers have very thin windows, allowing its application in low power beams. Measurements were made at four different depths of 1.0 to 4.0 mm extrapolation chamber, 1.0 mm interval, for each reference radiation. The study showed that there is a variable energy dependence on the volume of the extrapolation chamber. In other analysis, it is concluded that the energy dependence of extrapolation chamber becomes smaller when using the slope of the ionization current versus depth for the different radiation reference; this shows that the extrapolation technique, used for the absorbed dose calculation, reduces the uncertainty associated with the influence of the response variation with energy radiation

  7. Energy balance measurement

    DEFF Research Database (Denmark)

    Dhurandhar, N V; Schoeller, D; Brown, A W

    2015-01-01

    Energy intake (EI) and physical activity energy expenditure (PAEE) are key modifiable determinants of energy balance, traditionally assessed by self-report despite its repeated demonstration of considerable inaccuracies. We argue here that it is time to move from the common view that self......-reports of EI and PAEE are imperfect, but nevertheless deserving of use, to a view commensurate with the evidence that self-reports of EI and PAEE are so poor that they are wholly unacceptable for scientific research on EI and PAEE. While new strategies for objectively determining energy balance...... of energy balance....

  8. Inverse planning of energy-modulated electron beams in radiotherapy

    International Nuclear Information System (INIS)

    Gentry, John R.; Steeves, Richard; Paliwal, Bhudatt A.

    2006-01-01

    The use of megavoltage electron beams often poses a clinical challenge in that the planning target volume (PTV) is anterior to other radiosensitive structures and has variable depth. To ensure that skin as well as the deepest extent of the PTV receives the prescribed dose entails prescribing to a point beyond the depth of peak dose for a single electron energy. This causes dose inhomogeneities and heightened potential for tissue fibrosis, scarring, and possible soft tissue necrosis. Use of bolus on the skin improves the entrant dose at the cost of decreasing the therapeutic depth that can be treated. Selection of a higher energy to improve dose homogeneity results in increased dose to structures beyond the PTV, as well as enlargement of the volume receiving heightened dose. Measured electron data from a linear accelerator was used as input to create an inverse planning tool employing energy and intensity modulation using bolus (e-IMRT TM ). Using tools readily available in a radiotherapy department, the applications of energy and intensity modulation on the central axis makes it possible to remove hot spots of 115% or more over the depths clinically encountered. The e-IMRT TM algorithm enables the development of patient-specific dose distributions with user-defined positions of peak dose, range, and reduced dose to points beyond the prescription point

  9. PLS beam position measurement and feedback system

    International Nuclear Information System (INIS)

    Huang, J.Y.; Lee, J.; Park, M.K.; Kim, J.H.; Won, S.C.

    1992-01-01

    A real-time orbit correction system is proposed for the stabilization of beam orbit and photon beam positions in Pohang Light Source. PLS beam position monitoring system is designed to be VMEbus compatible to fit the real-time digital orbit feedback system. A VMEbus based subsystem control computer, Mil-1553B communication network and 12 BPM/PS machine interface units constitute digital part of the feedback system. With the super-stable PLS correction magnet power supply, power line frequency noise is almost filtered out and the dominant spectra of beam obtit fluctuations are expected to appear below 15 Hz. Using DSP board in SCC for the computation and using an appropriate compensation circuit for the phase delay by the vacuum chamber, PLS real-time orbit correction system is realizable without changing the basic structure of PLS computer control system. (author)

  10. Generating and measuring nondiffracting vector Bessel beams

    CSIR Research Space (South Africa)

    Dudley, Angela L

    2013-09-01

    Full Text Available Nondiffracting vector Bessel beams are of considerable interest due to their nondiffracting nature and unique high-numerical-aperture focusing properties. Here we demonstrate their creation by a simple procedure requiring only a spatial light...

  11. 0n a possibility of measuring some characteristics of charged parpticle beams at the accelerator output

    International Nuclear Information System (INIS)

    Vajner, E.A.; Trukhanov, K.A.

    1979-01-01

    Possibility of determining current density by cross section of beam, angular and energy particle distributions at the outlet of accelerators by means of Vavilov-Cherenkov radiation is considered. Vavilov-Cherenkov radiation has been detected by means of the FEV-16 photomultiplier. Distribution of current density by beam cross section has been registered by means of the transfer method of beam ''image'' from the radiator to the mechanical or electronic television system. Measurement of angular distribution is based on using directivity parameters of Vavilov-Cherenkov radiation. A method based on using nonlinear section of beam current dependence on the refractive index of substance of radiator is suggested for obtaining energy distribution of the beam. Errors in measurements by means of the mentioned methods constitute 2-5% [ru

  12. MD 2197: Experimental studies of Landau damping by means of Beam Transfer Function measurements in the presence of beam-beam interactions and diffusive mechanisms

    CERN Document Server

    Tambasco, Claudia; Barranco Garcia, Javier; Boccardi, Andrea; Buffat, Xavier; Bruce, Roderik; Gasior, Marek; Hostettler, Michi; Lefevre, Thibaut; Louro Alves, Diogo Miguel; Metral, Elias; Persson, Tobias Hakan Bjorn; Pieloni, Tatiana; Pojer, Mirko; Salvachua Ferrando, Belen Maria; Solfaroli Camillocci, Matteo; CERN. Geneva. ATS Department

    2018-01-01

    Beam Transfer Function (BTF) measurements are direct measurement of the stability diagrams that define the stability threshold of coherent beam instabilities driven by the impedance. At the LHC, some coherent instabilities at flat top energy are still not fully understood and the BTF measurements provide a method to experimentally probe the Landau damping of the proton beams. The BTF response is sensitive to the particle distribution changes and contain information about the transverse tune spread in the beams. The BTF system has been installed in the LHC in the 2015 in order to investigate the Landau damping at different stages of the operational cycle, machine configurations (different octupole currents, crossing angles, tunes etc...) and in presence of beam-beam excited resonances that may provoke diffusion mechanisms with a consequence change of Landau damping. Past MDs showed some difficulties for the reconstruction of the stability diagram from BTF measurements and several improvements on the BTF sy...

  13. Modulator considerations for beam chopping in the low energy beam transport at the SSC Laboratory

    International Nuclear Information System (INIS)

    Anderson, D.; Pappas, G.

    1991-06-01

    Beam chopping in the low energy transport line at the Superconducting Super Collider Laboratory is accomplished using an electrostatic deflection system. LINAC requirements dictate the design of two modulators operating at 10 Hz with rise and fall times (as measured from approximately 10--99%) of ∼100 ns. Design of the first pulser, normally at 10 kV and pulsed to ground potential, utilizes a transformer-coupled diode-clamped solid state circuit to achieve the 2--35 μs pulse width range required. The second pulser, which pulses from ground to approximately 7 kV, relies on a series vacuum tube circuit. The current designs, as well as recent test results and other circuit topologies considered, will be presented. 6 refs

  14. Simulation of a low energy beam transport line

    International Nuclear Information System (INIS)

    Yang Yao; Liu Zhanwen; Zhang Wenhui; Ma Hongyi; Zhang Xuezhen; Zhao Hongwei; Yao Ze'en

    2012-01-01

    A 2.45 GHz electron cyclotron resonance intense proton source and a low energy beam transport line with dual-Glaser lens were designed and fabricated by Institute of Modern Physics for a compact pulsed hadron source at Tsinghua. The intense proton beams extracted from the ion source are transported through the transport line to match the downstream radio frequency quadrupole accelerator. Particle-in-cell code BEAMPATH was used to carry out the beam transport simulations and optimize the magnetic field structures of the transport line. Emittance growth due to space charge and spherical aberrations of the Glaser lens were studied in both theory and simulation. The results show that narrow beam has smaller aberrations and better beam quality through the transport line. To better match the radio frequency quadrupole accelerator, a shorter transport line is desired with sufficient space charge neutralization. (authors)

  15. Characterisation of a MOSFET-based detector for dose measurement under megavoltage electron beam radiotherapy

    Science.gov (United States)

    Jong, W. L.; Ung, N. M.; Tiong, A. H. L.; Rosenfeld, A. B.; Wong, J. H. D.

    2018-03-01

    The aim of this study is to investigate the fundamental dosimetric characteristics of the MOSkin detector for megavoltage electron beam dosimetry. The reproducibility, linearity, energy dependence, dose rate dependence, depth dose measurement, output factor measurement, and surface dose measurement under megavoltage electron beam were tested. The MOSkin detector showed excellent reproducibility (>98%) and linearity (R2= 1.00) up to 2000 cGy for 4-20 MeV electron beams. The MOSkin detector also showed minimal dose rate dependence (within ±3%) and energy dependence (within ±2%) over the clinical range of electron beams, except for an energy dependence at 4 MeV electron beam. An energy dependence correction factor of 1.075 is needed when the MOSkin detector is used for 4 MeV electron beam. The output factors measured by the MOSkin detector were within ±2% compared to those measured with the EBT3 film and CC13 chamber. The measured depth doses using the MOSkin detector agreed with those measured using the CC13 chamber, except at the build-up region due to the dose volume averaging effect of the CC13 chamber. For surface dose measurements, MOSkin measurements were in agreement within ±3% to those measured using EBT3 film. Measurements using the MOSkin detector were also compared to electron dose calculation algorithms namely the GGPB and eMC algorithms. Both algorithms were in agreement with measurements to within ±2% and ±4% for output factor (except for the 4 × 4 cm2 field size) and surface dose, respectively. With the uncertainties taken into account, the MOSkin detector was found to be a suitable detector for dose measurement under megavoltage electron beam. This has been demonstrated in the in vivo skin dose measurement on patients during electron boost to the breast tumour bed.

  16. Measurement of centroid trajectory of Dragon-I electron beam

    International Nuclear Information System (INIS)

    Jiang Xiaoguo; Wang Yuan; Zhang Wenwei; Zhang Kaizhi; Li Jing; Li Chenggang; Yang Guojun

    2005-01-01

    The control of the electron beam in an intense current linear induction accelerator (LIA) is very important. The center position of the electron beam and the beam profile are two important parameters which should be measured accurately. The setup of a time-resolved measurement system and a data processing method for determining the beam center position are introduced for the purpose of obtaining Dragon-I electron beam trajectory including beam profile. The actual results show that the centroid position error can be controlled in one to two pixels. the time-resolved beam centroid trajectory of Dragon-I (18.5 MeV, 2 kA, 90 ns) is obtained recently in 10 ns interval, 3 ns exposure time with a multi-frame gated camera. The results show that the screw movement of the electron beam is mainly limited in an area with a radius of 0.5 mm and the time-resolved diameters of the beam are 8.4 mm, 8.8 mm, 8.5 mm, 9.3 mm and 7.6 mm. These results have provided a very important support to several research areas such as beam trajectory tuning and beam transmission. (authors)

  17. Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

    Directory of Open Access Journals (Sweden)

    F. J. Cullinan

    2015-11-01

    Full Text Available The Compact Linear Collider (CLIC requires beam position monitors (BPMs with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3 at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the reference cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2/3  ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Finally, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.

  18. Pulsed magnet systems for high energy physics beam lines

    International Nuclear Information System (INIS)

    Praeg, W.F.

    1975-01-01

    During the past years pulsed magnet systems have been developed at Argonne National Laboratory to transport beam bursts of charged high energy particles of the Zero Gradient Synchrotron (ZGS) facility. The particular features of the switching circuits, the power supplies and the magnets are described. Included are septum, quadrupole, beam shutter and bending magnets with energies ranging from 25 J to 100 kJ. The degree to which magnet current must be repeated and held constant (flattopped) during beam spill varies from +-5 percent for a beam shutter magnet to +-0.005 percent for a bending magnet; the duration of flattop ranges from a few μs to many ms. (U.S.)

  19. On the importance of low-energy beta-beams for supernova neutrino physics

    International Nuclear Information System (INIS)

    Jachowicz, N.; McLaughlin, G.C.

    2005-01-01

    Beta beams, which are neutrino beams produced by the beta decay of nuclei that have been accelerated to high gamma factor, were original proposed for high energy applications, such as the measurement of the third neutrino mixing angle θ 13 . Volpe suggested that a beta beam run at lower gamma factor, would be useful for neutrino measurements in the tens of MeV range. We suggest to exploit the flexibility these beta beam facilities offer, combined with the fact that beta-beam neutrino energies overlap with supernova-neutrino energies, to construct 'synthetic' spectra that approximate an incoming supernova-neutrino energy-distribution. Using these constructed spectra we are able to reproduce total and differential folded supernova-neutrino cross-sections very accurately. We illustrate this technique using Deuterium, 16 O, and 208 Pb. This technique provides an easy and straightforward way to apply the results of a beta-beam neutrino-nucleus measurement to the corresponding supernova-neutrino detector, virtually eliminating potential uncertainties due to nuclear-structure calculations. (author)

  20. Beam diffusion measurements using collimator scans in the LHC

    Science.gov (United States)

    Valentino, Gianluca; Aßmann, Ralph; Bruce, Roderik; Burkart, Florian; Previtali, Valentina; Redaelli, Stefano; Salvachua, Belen; Stancari, Giulio; Valishev, Alexander

    2013-02-01

    The time evolution of beam losses during a collimator scan provides information on halo diffusion and population. This is an essential input for machine performance characterization and for the design of collimation systems. Beam halo measurements in the CERN Large Hadron Collider were conducted through collimator scrapings in a dedicated beam study for the first time at 4 TeV. Four scans were performed with two collimators, in the vertical plane for beam 1 and horizontally for beam 2, before and after bringing the beams into collisions. Inward and outward steps were performed. A diffusion model was used to interpret the observed loss rate evolution in response to the collimator steps. With this technique, diffusion coefficients were estimated as a function of betatron oscillation amplitude from approximately 3 to 7 standard deviations of the transverse beam distribution. A comparison of halo diffusion and core emittance growth rates is also presented.

  1. Beam diffusion measurements using collimator scans in the LHC

    Directory of Open Access Journals (Sweden)

    Gianluca Valentino

    2013-02-01

    Full Text Available The time evolution of beam losses during a collimator scan provides information on halo diffusion and population. This is an essential input for machine performance characterization and for the design of collimation systems. Beam halo measurements in the CERN Large Hadron Collider were conducted through collimator scrapings in a dedicated beam study for the first time at 4 TeV. Four scans were performed with two collimators, in the vertical plane for beam 1 and horizontally for beam 2, before and after bringing the beams into collisions. Inward and outward steps were performed. A diffusion model was used to interpret the observed loss rate evolution in response to the collimator steps. With this technique, diffusion coefficients were estimated as a function of betatron oscillation amplitude from approximately 3 to 7 standard deviations of the transverse beam distribution. A comparison of halo diffusion and core emittance growth rates is also presented.

  2. Radiation degradation of marine polysaccharides by low energy electron beam

    International Nuclear Information System (INIS)

    Yoshii, Fumio; Nagasawa, Naotsugu; Kume, Tamikazu

    2003-01-01

    The radiation degradations of marine polysaccharides by both gamma Co-60 and electron beam irradiations are investigated. Polysaccharides and oligosaccharides can be produced by degradation of corresponding polysaccharides including marine polysaccharides such as alginates, chitin chitosan and carrageenan. The viscosity of alginate, chitosan and carrageenan solution decreases markedly with increase of the low energy electron beam irradiation time and the beam current. Furthermore, the viscosity is reduced sharply in short time for polysaccharide solution with low concentration, for instance carrageenan solution of 1%. (author)

  3. Dependence of bunch energy loss in cavities on beam velocity

    Directory of Open Access Journals (Sweden)

    Sergey S. Kurennoy

    1999-03-01

    Full Text Available Beam energy loss in a cavity can be easily computed for a relativistic bunch using time-domain codes like MAFIA or ABCI. However, for nonrelativistic beams the problem is more complicated because of difficulties with its numerical formulation in the time domain. We calculate the cavity loss factors for a bunch in frequency domain as a function of its velocity and compare results with the relativistic case.

  4. Beam dynamics and commissioning of low and medium energy H- beam at Linac4

    CERN Document Server

    Satri, Masoomeh Yarmohammadi; Lombardi, Alessandra; Lamehi-Rachti , Mohammad

    The First step of the CERN Large Hadron Collider injectors upgrade (LIU) project is Linac4. It accelerates H- ions to 160 MeV in an 80 m long accelerator housed in a tunnel 12 m underground, presently under construction. It will replace the present 50 MeV proton Linac2 as injector of the proton accelerator complex to increase the LHC luminosity. It consists of a 45 keV RF volume source, a twosolenoid Low Energy Beam Transport (LEBT), a 352.2 MHz Radio Frequency Quadrupole (RFQ) accelerating the beam to 3 MeV, a Medium Energy Beam Transport (MEBT) line. The MEBT houses a fast chopper to selectively remove unwanted micro-bunches in the 352 MHz sequence and avoid losses at capture in the CERN PSB (1 MHz). After chopping, the beam acceleration continues by a 50 MeV Drift Tube Linac (DTL), a 100 MeV Cell-Coupled Drift Tube Linac and a Pi-Mode Structure bringing the beam to the final energy of 160 MeV. Linac4 has been commissioned with a temporary source up to 12 MeV. The beam commissioning stages of Linac4 in LEBT...

  5. Measurement of proton-beam parameters by means of digital television diagnostic system

    International Nuclear Information System (INIS)

    Vazhenin, V.A.; Borovkov, S.D.; Evtikhiev, A.V.

    1992-01-01

    A method is described for measurement of the parameters of pulse-packet beams by means of a digital television diagnostic system. Results of tests of the system in measurement of the parameters of a proton beam with an energy of 1.35 GeV in the U-70 circular accelerator and results of measurements of the energy spectrum of the 30-MeV proton beam of the LU-30 linear accelerator are given. The possibility is shown of using the system to measure the integrated characteristics of an entire beam-pulse packet as well as the characteristics of individual pulses with a period of 60 msec. 6 refs., 4 figs., 1 tab

  6. Measuring charge density of electron beam single nanosecond pulses

    International Nuclear Information System (INIS)

    Gonchar, A.I.; Nesterenko, V.S.; Fazkullin, V.A.

    1982-01-01

    A description is presented of a probe design and electrometric repeater circuit and technique for measuring the charge (current) density of electron beam single pulses by integrating current at a reference capacitor with a subsequent registering of voltage across the capacitor. The probe consists of a band-type signal electrodes and two oval cross-section sleeves: external and internal with larger and smaller rectangular openings, respectively. The external sleeve has antidynatron grid located over the hole. The design employs integer nickel sleever - the cores of electron tube cathodes. The signal electrode is made of nickel band 0.15 mm thick. The probe elements are insulated from each other along the whole length with a layer of teflon band (30 μm), with rectangular openings cut in compliance with the sleeve openings. The measurement range is from 0.4x10 - 9 to 1x10 - 7 C/cm 2 . The rated accuracy of measurements is no worse than +-5% for the beam energy of 0.2 to 3 KeV. The ultimate parameters the charge density - 6 C/cm 2 and direct current density 3 mA/cm 2 - are specified by the breakdown voltage (200 V) of the input capacitor and probe insulation

  7. Beamed-Energy Propulsion (BEP): Considerations for Beaming High Energy-Density Electromagnetic Waves Through the Atmosphere

    Science.gov (United States)

    Manning, Robert M.

    2015-01-01

    A study to determine the feasibility of employing beamed electromagnetic energy for vehicle propulsion within and outside the Earth's atmosphere was co-funded by NASA and the Defense Advanced Research Projects Agency that began in June 2010 and culminated in a Summary Presentation in April 2011. A detailed report entitled "Beamed-Energy Propulsion (BEP) Study" appeared in February 2012 as NASA/TM-2012-217014. Of the very many nuances of this subject that were addressed in this report, the effects of transferring the required high energy-density electromagnetic fields through the atmosphere were discussed. However, due to the limitations of the length of the report, only a summary of the results of the detailed analyses were able to be included. It is the intent of the present work to make available the complete analytical modeling work that was done for the BEP project with regard to electromagnetic wave propagation issues. In particular, the present technical memorandum contains two documents that were prepared in 2011. The first one, entitled "Effects of Beaming Energy Through the Atmosphere" contains an overview of the analysis of the nonlinear problem inherent with the transfer of large amounts of energy through the atmosphere that gives rise to thermally-induced changes in the refractive index; application is then made to specific beamed propulsion scenarios. A brief portion of this report appeared as Appendix G of the 2012 Technical Memorandum. The second report, entitled "An Analytical Assessment of the Thermal Blooming Effects on the Propagation of Optical and Millimeter- Wave Focused Beam Waves For Power Beaming Applications" was written in October 2010 (not previously published), provides a more detailed treatment of the propagation problem and its effect on the overall characteristics of the beam such as its deflection as well as its radius. Comparisons are then made for power beaming using the disparate electromagnetic wavelengths of 1.06 microns and 2

  8. Experimental assessment of out-of-field dose components in high energy electron beams used in external beam radiotherapy.

    Science.gov (United States)

    Alabdoaburas, Mohamad M; Mege, Jean-Pierre; Chavaudra, Jean; Bezin, Jérémi Vũ; Veres, Atilla; de Vathaire, Florent; Lefkopoulos, Dimitri; Diallo, Ibrahima

    2015-11-08

    The purpose of this work was to experimentally investigate the out-of-field dose in a water phantom, with several high energy electron beams used in external beam radiotherapy (RT). The study was carried out for 6, 9, 12, and 18 MeV electron beams, on three different linear accelerators, each equipped with a specific applicator. Measurements were performed in a water phantom, at different depths, for different applicator sizes, and off-axis distances up to 70 cm from beam central axis (CAX). Thermoluminescent powder dosimeters (TLD-700) were used. For given cases, TLD measurements were compared to EBT3 films and parallel-plane ionization chamber measurements. Also, out-of-field doses at 10 cm depth, with and without applicator, were evaluated. With the Siemens applicators, a peak dose appears at about 12-15 cm out of the field edge, at 1 cm depth, for all field sizes and energies. For the Siemens Primus, with a 10 × 10 cm(²) applicator, this peak reaches 2.3%, 1%, 0.9% and 1.3% of the maximum central axis dose (Dmax) for 6, 9, 12 and 18 MeV electron beams, respectively. For the Siemens Oncor, with a 10 × 10 cm(²) applicator, this peak dose reaches 0.8%, 1%, 1.4%, and 1.6% of Dmax for 6, 9, 12, and 14 MeV, respectively, and these values increase with applicator size. For the Varian 2300C/D, the doses at 12.5 cm out of the field edge are 0.3%, 0.6%, 0.5%, and 1.1% of Dmax for 6, 9, 12, and 18 MeV, respectively, and increase with applicator size. No peak dose is evidenced for the Varian applicator for these energies. In summary, the out-of-field dose from electron beams increases with the beam energy and the applicator size, and decreases with the distance from the beam central axis and the depth in water. It also considerably depends on the applicator types. Our results can be of interest for the dose estimations delivered in healthy tissues outside the treatment field for the RT patient, as well as in studies exploring RT long-term effects.

  9. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators

    Energy Technology Data Exchange (ETDEWEB)

    McLaughlin, David J.; Shikhaliev, Polad M.; Matthews, Kenneth L. [Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803-4001 (United States); Hogstrom, Kenneth R., E-mail: hogstrom@lsu.edu; Carver, Robert L.; Gibbons, John P. [Mary Bird Perkins Cancer Center, 4950 Essen Lane, Baton Rouge, Louisiana 70809-3482 and Department of Physics and Astronomy, Louisiana State University, 202 Nicholson Hall, Baton Rouge, Louisiana 70803-4001 (United States); Clarke, Taylor; Henderson, Alexander; Liang, Edison P. [Physics and Astronomy Department, Rice University, 6100 Main MS-61, Houston, Texas 77005-1827 (United States)

    2015-09-15

    Purpose: The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. Methods: An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed using a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7–20 MeV) of an Elekta Infinity radiotherapy accelerator. Results: Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to slightly lower

  10. Permanent-magnet energy spectrometer for electron beams from radiotherapy accelerators.

    Science.gov (United States)

    McLaughlin, David J; Hogstrom, Kenneth R; Carver, Robert L; Gibbons, John P; Shikhaliev, Polad M; Matthews, Kenneth L; Clarke, Taylor; Henderson, Alexander; Liang, Edison P

    2015-09-01

    The purpose of this work was to adapt a lightweight, permanent magnet electron energy spectrometer for the measurement of energy spectra of therapeutic electron beams. An irradiation geometry and measurement technique were developed for an approximately 0.54-T, permanent dipole magnet spectrometer to produce suitable latent images on computed radiography (CR) phosphor strips. Dual-pinhole electron collimators created a 0.318-cm diameter, approximately parallel beam incident on the spectrometer and an appropriate dose rate at the image plane (CR strip location). X-ray background in the latent image, reduced by a 7.62-cm thick lead block between the pinhole collimators, was removed using a fitting technique. Theoretical energy-dependent detector response functions (DRFs) were used in an iterative technique to transform CR strip net mean dose profiles into energy spectra on central axis at the entrance to the spectrometer. These spectra were transformed to spectra at 95-cm source to collimator distance (SCD) by correcting for the energy dependence of electron scatter. The spectrometer was calibrated by comparing peak mean positions in the net mean dose profiles, initially to peak mean energies determined from the practical range of central-axis percent depth-dose (%DD) curves, and then to peak mean energies that accounted for how the collimation modified the energy spectra (recalibration). The utility of the spectrometer was demonstrated by measuring the energy spectra for the seven electron beams (7-20 MeV) of an Elekta Infinity radiotherapy accelerator. Plots of DRF illustrated their dependence on energy and position in the imaging plane. Approximately 15 iterations solved for the energy spectra at the spectrometer entrance from the measured net mean dose profiles. Transforming those spectra into ones at 95-cm SCD increased the low energy tail of the spectra, while correspondingly decreasing the peaks and shifting them to slightly lower energies. Energy calibration

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

    Science.gov (United States)

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

    2017-08-01

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

  12. Determination of the LEP beam energy through {zeta}{gamma} events and the measurements of 3 neutral gauge bosons in the ALEPH experiment; Determination de l'energie du faisceau du LEP a l'aide des evenements {zeta}{gamma} et mesures de couplages a trois bosons de jauge neutres dans l'experience ALEPH

    Energy Technology Data Exchange (ETDEWEB)

    Trocme, B

    2001-04-01

    After six years of data taking at Z peak, LEP beam energy continuously raised to finally reach 104.5 GeV, allowing notably W pairs production. Z resonance remains however important trough radiative return process; a hard photon being emitted in initial state, the centre of mass energy is reduced to an effective value close to Z mass. These events taken by Aleph experiment between 1998 and 2000 have been analysed following two distinct approaches, that are detailed in this thesis. With nearly 700 pb{sup -1} taken by each experiment, it is obvious that final W mass measurement- one major goal of LEP2 program- will be dominated by systematic error, with a large contribution from the uncertainty on the LEP beam energy. A fit of the radiative return peak position allows an original determination of the latter. Being not only a single measurement, this method is also a powerful tool to check techniques used in W mass measurement. Moreover, Z{gamma} events final states are similar to processes with a vertex involving three neutral gauge bosons. Anomalous production cross section, as well as deformed kinematic distributions, can be a probe of new physic that lies at much higher energy scales. A search for such phenomena has also been performed. (author)

  13. ALICE EMCal Reconstructable Energy Non-Linearity From Test Beam Monte Carlo

    CERN Document Server

    Carter, Thomas Michael

    2017-01-01

    Calorimeters play many important roles in modern high energy physics detectors, such as event selection, triggering, and precision energy measurements. EMCal, in the case of the ALICE experiment provides triggering on high energy jets, improves jet quenching study measurement bias and jet energy resolution, and improves electron and photon measurements [3]. With the EMCal detector in the ALICE experiment taking on so many important roles, it is important to fully understand, characterize and model its interactions with particles. In 2010 SPS and PS electron test beam measurements were performed on an EMCal mini-module [2]. Alongside this, the test beam setup and geometry was recreated in Geant4 by Nico [1]. Figure 1 shows the reconstructable energy linearity for the SPS test beam data and that obtained from the test beam monte carlo, indicating the amount of energy deposit as hits in the EMCal module. It can be seen that for energies above ∼ 100 GeV there is a significant drop in the reconstructableenergym...

  14. Studies on the dose distribution and treatment technique of high energy electron beams

    International Nuclear Information System (INIS)

    Lee, D.H.; Chu, S.S.

    1978-01-01

    Some important properties of high energy electron beams from the linear accelerator, LMR-13, installed in the Yonsei Cancer Center were studied. The results of experimental studies on the problems associated with the 8, 10, and 12 MeV electron beam therapy were as followings; The ionization type dosemeters calibrated by 90 Sr standard source were suitable to the measurements of the outputs and the obsorbed doses in accuracy point of view, and dose measurements using ionization chambers were difficult when measuring doses in small field size and the regions of rapid fall off. The electron energies were measured precisely with an energy spectrometer, and the practical electron energy was calculated within 5% error in the maximum range of the high energy electron beam in water. The correcting factors of perturbated dose distributions owing to radiation field, energy, and materials of the treatment cone were checked and described systematically and thus the variation of dose distributions due to the non-homogeneities of tissues and slopping skin surfaces were completely compensated. The electron beams were adequately diffused using the scatterers, and minimized the bremsstrahlung, irradiation field size, and materials of scatterers. Thus, the therapeutic capacity with the limited electron energy could be extended by improving the dose distributions. (author)

  15. Performance of SPS Low transition Energy Optics for LHC Ion Beam

    CERN Document Server

    Antoniou, F; Bartosik, H; Bohl, T; Cave, SC; Cornelis, K; Manglunki, D; Papaphilippou, Y

    2013-01-01

    An optics with low transition energy has been developed in the SPS for removing intensity limitations of the LHC proton beam and has become operational towards the second part of the 2012 LHC proton run. The impact of this optics in the performance of the LHC ion beam is studied here, especially with respect to collective effects, at the SPS injection energy, based both on modelling and beam measurements. In particular, the potential gain of the increased beam sizes provided by this optics, with respect to losses and emittance blow up due to space-charge and Intrabeam Scattering (IBS) is evaluated. The measured lifetime is compared with the one provided by the Touschek effect and its interplay with RF noise is studied.

  16. 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...

  17. Observations and measurements of dynamic effects due to beam-beam interactions in the LHC and extrapolation to the FCC-hh

    CERN Document Server

    Goncalves Jorge, Patrik

    The Future Circular hadron-hadron Collider (FCC-hh) is a design study for a 100 TeV centre-of-mass energy. The dynamics of the beams in such a collider poses many challenges, in particular the amount of energy stored in each beam (8.4 GJ) makes them very destructive and therefore requires a tight control of the machine and beam parameters during the full cycle in order to avoid damages and reach the collider designed performances. The FCC-hh features an increase of the beam brightness during the cycle due to the presence of synchrotron radiation damping at high energy. As a result, the electromagnetic forces that the two beams exert on each other, the so-called beam-beam forces, are enhanced and might become an issue for the safe operation of the machine. In this new regime, the impact of the beam-beam interaction on the optics becomes non-negligible. In this master thesis, for the first time, the impact of the beam-beam interaction on the optics ($\\beta$-beating) is measured in a hadron collider (LHC). The e...

  18. Designing Light Beam Transmittance Measuring Tool Using a Laser Pointer

    Science.gov (United States)

    Nuroso, H.; Kurniawan, W.; Marwoto, P.

    2016-08-01

    A simple instrument used for measuring light beam transmittance percentage made of window film has been developed. The instrument uses a laser pointer of 405 nm and 650 nm ±10% as a light source. Its accuracy approaches 80%. Transmittance data was found by comparing the light beam before and after passing the window film. The light intensity measuring unit was deleted by splitting the light source into two beams through a beam splitter. The light beam was changed into resistance by a NORP12 LDR sensor designed at a circuit of voltage divider rule of Khirchoff's laws. This conversion system will produce light beam intensity received by the sensor to become an equal voltage. This voltage will, then, be presented on the computer screen in the form of a real time graph via a 2.0 USB data transfer.

  19. The Beam Energy Tracking System of the LHC Beam Dumping System

    CERN Document Server

    Barlow, R A; Carlier, E; Gräwer, G; Voumard, N; Gjelsvik, R

    2005-01-01

    The LHC Beam Dumping System (LBDS) of the Large Hadron Collider (LHC), presently under construction at CERN, will be installed around the straight section 6. It comprises per ring 15 horizontally deflecting extraction kickers, followed by 1 quadrupole, 15 vertically deflecting steel septum magnets, 10 dilution kickers and, in a separate cavern several hundred meters away, an external absorber assembly. A beam dump request can occur at any moment during the operation of the collider, from injection at 450 GeV up to top energy at 7 TeV. The Beam Energy Tracking System (BETS) monitors the deflection strength of each active element of the LBDS with respect to the beam energy in order to guarantee the correct extraction trajectory over the complete operational range and under all operational conditions. Its main functions are the acquisition of the beam energy, the generation of the kick strength reference signals for the extraction and dilution kickers, the continuous checking that the kicker high voltage generat...

  20. Nonlinear optical beam manipulation and high energy beam propagation through the atmosphere; Proceedings of the Meeting, Los Angeles, CA, Jan. 18-20, 1989

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, R.A.; Wilson, L.E.

    1989-01-01

    Various papers on nonlinear optical beam manipulation and high-energy beam propagation through the atmosphere are presented. Individual topics addressed include: suppression of Raman amplification using large Stokes seeds, review of multiple-short-pulse SBS experiments and theory, laser-induced gratings for beam manipulation in a gas, considerations for computing realistic atmospheric distortion parameter profiles, effect of turbulent diffusion on laser propagation, use of multiple photon processes in krypton for laser guiding of electron beams, effect of ionization on intense electron beam propagation in low-pressure media, lidar measurements of the troposphere and middle atmosphere, seasonal and diurnal changes in cloud obscuration to visible and IR energy transmission, new cloud composite climatologies using meteorological satellite imagery, effect of neutral atmospheric structure on beam propagation, small-scale electron density fluctuations in a disturbed ionospheric environment, and SDIO radio frequency communications in a structured environment.

  1. Measurement of the SMC muon beam polarisation using the asymmetry in the elastic scattering off polarised electrons

    Energy Technology Data Exchange (ETDEWEB)

    Adams, D.; Adeva, B.; Akdogan, T.; Arik, E.; Arvidson, A.; Badelek, B; Bardin, G.; Baum, G.; Berglund, P.; Betev, L.; Birsa, R.; Bjoerkholm, P.; Bonner, B.E.; Botton, N. de E-mail: nico.de.botton@cern.ch; Boutemeur, M.; Bradamante, F.; Bravar, A.; Bressan, A.; Bueltmann, S.; Burtin, E.; Cavata, C.; Clocchiatti, M.; Crabb, D.; Cranshaw, J.; Cuhadar, T.; Dalla Torre, S.; Dantzig, R. van; Derro, B.; Deshpande, A.; Dhawan, S.; Dulya, C.; Dyring, A.; Eichblatt, S.; Faivre, J.C.; Fasching, D.; Feinstein, F.; Fernandez, C.; Forthmann, S.; Frois, B.; Gallas, A.; Garzon, J.A.; Gatignon, L.; Gaussiran, T.; Gilly, H.; Giorgi, M.; Goeler, E. von; Goertz, S.; Golutvin, I.A.; Gracia, G.; Groot, N. de; Grosse Perdekamp, M.; Haft, K.; Harrach, D. von; Hasegawa, T.; Hautle, P.; Hayashi, N.; Heusch, C.A.; Horikawa, N.; Hughes, V.W.; Igo, G.; Ishimoto, S.; Iwata, T.; Kabuss, E.M.; Kageya, T.; Karev, A.; Kessler, H.J.; Ketel, T.J.; Kiryluk, J.; Kiryushin, I.; Kishi, A.; Kisselev, Yu.; Klostermann, L.; Kraemer, D.; Krivokhijine, V.; Kroeger, W.; Kukhtin, V.; Kurek, K.; Kyynaeraeinen, J.; Lamanna, M.; Landgraf, U.; Le Goff, J.M.; Lehar, F.; Lesquen, A. de; Lichtenstadt, J.; Lindqvist, T.; Litmaath, M.; Lowe, M.; Magnon, A.; Mallot, G.K.; Marie, F.; Martin, A.; Martino, J.; Matsuda, T.; Mayes, B.; McCarthy, J.S.; Medved, K.; Meyer, W.; Middelkoop, G. van; Miller, D.; Miyachi, Y.; Mori, K.; Moromisato, J.; Nagaitsev, A.; Nassalski, J.; Naumann, L.; Niinikoski, T.O.; Oberski, J.E.J.; Ogawa, A.; Ozben, C.; Pereira, H.; Perrot-Kunne, F.; Peshekhonov, D.; Piegaia, R.; Pinsky, L.; Platchkov, S.; Plo, M.; Pose, D.; Postma, H.; Pretz, J.; Pussieux, T.; Raedel, G.; Rijllart, A.; Reicherz, G.; Roberts, J.B.; Rock, S.; Rodriguez, M.; Rondio, E.; Ropelewski, L.; Sabo, I.; Saborido, J.; Sandacz, A; Savin, I.; Schiavon, P.; Schiller, A.; Schueler, K.P.; Seitz, R.; Semertzidis, Y.; Sergeev, S.; Shanahan, P.; Sichtermann, E.P.; Simeoni, F.; Smirnov, G.I.; Staude, A.; Steinmetz, A. [and others

    2000-03-21

    A muon beam polarimeter was built for the SMC experiment at the CERN SPS, for beam energies of 100 and 190 GeV. The beam polarisation is determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed. At muon energies of 100 and 190 GeV the measured polarisation is P{sub {mu}}=-0.80{+-}0.03 (stat.){+-}0.02 (syst.) and P{sub {mu}}=-0.797{+-}0.011 (stat.){+-}0.012 (syst.), respectively. These results agree with measurements of the beam polarisation using a shape analysis of the decay positron energy spectrum.

  2. Study of ECAL Energy Reconstruction Algorithms in Test Beam Data

    CERN Document Server

    Seez, Christopher

    1998-01-01

    The well understood data set taken in the test beam in August 1997, which has previously been used to study lateral uniformity of energy response, is used to investigate the performance of different sized summation areas for energy reconstruction. Results for 5x5, 4x4 and 3x3 areas are presented and compared with shower simulation results. The correction of the energy response as a function of position is also investigated.

  3. A Layer Correlation Technique for Pion Energy Calibration at the 2004 ATLAS Combined Beam Test

    CERN Document Server

    Grahn, Karl-Johan

    2009-01-01

    A new method for calibrating the hadron response of a segmented calorimeter is developed. It is based on a principal component analysis of the calorimeter layer energy deposits, exploiting longitudinal shower development information to improve the measured energy resolution. Corrections for invisible hadronic energy and energy lost in dead material in front of and between the ATLAS calorimeters were calculated with simulated Geant4 Monte Carlo events and used to reconstruct the energy of pions impinging on the calorimeters during the 2004 Barrel Combined Beam Test at the CERN H8 area. For pion beams with energies between 20 and 180 GeV, the particle energy is reconstructed within 3% and the energy resolution is improved by about 20% compared to the electromagnetic scale.

  4. Beam size measurement of the stored electron beam at the APS storage ring using pinhole optics

    International Nuclear Information System (INIS)

    Cai, Z.; Lai, B.; Yun, W.

    1995-01-01

    Beam sizes of the stored electron beam at the APS storage ring were measured using pinhole optics and bending magnet x-rays in single-bunch and low-current mode. A pinhole of 25 μm and a fast x-ray imaging system were located 23.8 m and 35.4 m from the source, respectively. The x-ray imaging system consists of a CdWO 4 scintillation crystal 60 μm thick, an optical imaging system, and a CCD detector. A measurement time of a few tenths of a second was obtained on a photon beam of E>30 keV produced in a bending magnet from a 7-GeV electron beam of 2mA current. The measured vertical and horizontal sizes of the electron beam were in reasonable agreement with the expected values

  5. Measurement of surface phonon dispersion relations for LiF, NaF, and KCl through energy-analysed inelastic scattering of a helium atomic beam

    International Nuclear Information System (INIS)

    Doak, R.B.

    1981-01-01

    A crystal surface terminates abruptly one dimension of lattice periodicity, constituting a lattice defect with concomitant localized modes of vibration, termed surface phonons. Such surface phonons have previously been investigated in the long wavelength, non-dispersive regime. The present work reports the first observation of surface phonons in the short wavelength, dispersive range. The data allow for the first time a surface phonon dispersion curve to be plotted completely from origin to edge of the surface Brillouin zone. Measurements were made of phonons along the (anti GAMMA anti M) and (anti GAMMA anti X) azimuths of the LiF(001) surface and along the azimuth of NaF(001) and KC1(001) surfaces. The results are in substantial agreement with theoretical predictions, although for LiF the measured Rayleigh dispersion curve at M lies appreciably below the theoretical value, possibly reflecting the effects of surface relaxation. (orig.)

  6. Modeled and Measured Dynamics of a Composite Beam with Periodically Varying Foam Core

    Science.gov (United States)

    Cabell, Randolph H.; Cano, Roberto J.; Schiller, Noah H.; Roberts Gary D.

    2012-01-01

    The dynamics of a sandwich beam with carbon fiber composite facesheets and foam core with periodic variations in material properties are studied. The purpose of the study is to compare finite element predictions with experimental measurements on fabricated beam specimens. For the study, three beams were fabricated: one with a compliant foam core, a second with a stiffer core, and a third with the two cores alternating down the length of the beam to create a periodic variation in properties. This periodic variation produces a bandgap in the frequency domain where vibrational energy does not readily propagate down the length of the beam. Mode shapes and natural frequencies are compared, as well as frequency responses from point force input to velocity response at the opposite end of the beam.

  7. Measurement of power density distribution and beam waist simulation for electron beam

    International Nuclear Information System (INIS)

    Shen, Chunlong; Peng, Yong; Wang, Kehong; Zhou, Qi

    2013-01-01

    The study aims to measure the power density distribution of the electron beam (EB) for further estimating its characteristics. A compact device combining deflection signal controller and current signal acquisition circuit of the EB was built. A software modelling framework was developed to investigate structural parameters of the electron beam. With an iterative algorithm, the functional relationship between the electron beam power and its power density was solved and the corresponding contour map of power density distribution was plotted through isoline tracking approach. The power density distribution of various layers of cross-section beam was reconstructed for beam volume by direct volume rendering technique. The further simulation of beam waist with all-known marching cubes algorithm reveals the evolution of spatial appearance and geometry measurement principle was explained in detail. The study provides an evaluation of promising to replace the traditional idea of EB spatial characteristics. - Highlights: ► We build a framework for measuring power density distribution for electron beam. ► We capture actual electron and build transient spatial power distribution for EB. ► Tracing algorithm of power density contour for cross-section was designed. ► The volume and waist of the beam are reconstructed in 4D mode. ► Geometry measurement is finished which is befit for designing of process welding.

  8. Low (50 keV) and medium (∼10 MeV) energy radioactive beams at Louvain-la-Neuve

    International Nuclear Information System (INIS)

    Huyse, M.; Decrock, P.; Dendooven, P.; Reusen, G.; Duppen, P. Van; Wauters, J.

    1991-01-01

    Low energy radioactive beams are produced at the Leuven Isotope Separator On Line (LISOL) facility in Louvain-la-Neuve. The beams are used for standard nuclear spectroscopy studies and for nuclear orientation on line measurements. Since September 1987 a new project has been started up to accelerate radioactive beams to energies in the range of astrophysical interest. A beam of 10 6 13 N ions per seconde with an energy of 8.5 MeV has been produced last June. (author) 11 refs.; 1 fig.; 1 tab

  9. Fission cross section measurements at intermediate energies

    International Nuclear Information System (INIS)

    Laptev, Alexander

    2005-01-01

    The activity in intermediate energy particle induced fission cross-section measurements of Pu, U isotopes, minor actinides and sub-actinides in PNPI of Russia is reviewed. The neutron-induced fission cross-section measurements are under way in the wide energy range of incident neutrons from 0.5 MeV to 200 MeV at the GNEIS facility. In number of experiments at the GNEIS facility, the neutron-induced fission cross sections were obtained for many nuclei. In another group of experiments the proton-induced fission cross-section have been measured for proton energies ranging from 200 to 1000 MeV at 100 MeV intervals using the proton beam of PNPI synchrocyclotron. (author)

  10. Polarisation measurements on e sup+- beams

    CERN Document Server

    Long, K

    2002-01-01

    The current status of e sup+--beam polarimetry at the HERA ep collider is reviewed, giving the performance achieved to date and the status of the various upgrade projects together with a summary of the expected performance. In addition, the polarimeter that has been proposed for the TESLA e sup + e sup - collider is described.

  11. Narrow beam dosimetry for high-energy hadrons and electrons

    CERN Document Server

    Pelliccioni, M; Ulrici, Luisa

    2001-01-01

    Organ doses and effective dose were calculated with the latest version of the Monte Carlo transport code FLUKA in the case of an anthropomorphic mathematical model exposed to monoenergetic narrow beams of protons, pions and electrons in the energy range 10°— 400 GeV. The target organs considered were right eye, thyroid, thymus, lung and breast. Simple scaling laws to the calculated values are given. The present data and formula should prove useful for dosimetric estimations in case of accidental exposures to high-energy beams.

  12. High Energy Beam Impacts on Beam Intercepting Devices: Advanced Numerical Methods and Experimental Set-Up

    CERN Document Server

    Bertarelli, A; Carra, F; Cerutti, F; Dallocchio, A; Mariani, N; Timmins, M; Peroni, L; Scapin, M

    2011-01-01

    Beam Intercepting Devices are potentially exposed to severe accidental events triggered by direct impacts of energetic particle beams. State-of-the-art numerical methods are required to simulate the behaviour of affected components. A review of the different dynamic response regimes is presented, along with an indication of the most suited tools to treat each of them. The consequences on LHC tungsten collimators of a number of beam abort scenarios were extensively studied, resorting to a novel category of numerical explicit methods, named Hydrocodes. Full shower simulations were performed providing the energy deposition distribution. Structural dynamics and shock wave propagation analyses were carried out with varying beam parameters, identifying important thresholds for collimator operation, ranging from the onset of permanent damage up to catastrophic failure. Since the main limitation of these tools lies in the limited information available on constitutive material models under extreme conditions, a dedica...

  13. High Energy Beam Impacts on Beam Intercepting Devices: Advanced Numerical Methods and Experimental Set-up

    CERN Document Server

    Bertarelli, A; Carra, F; Cerutti, F; Dallocchio, A; Mariani, N; Timmins, M; Peroni, L; Scapin, M

    2011-01-01

    Beam Intercepting Devices are potentially exposed to severe accidental events triggered by direct impacts of energetic particle beams. State-of-the-art numerical methods are required to simulate the behaviour of affected components. A review of the different dynamic response regimes is presented, along with an indication of the most suited tools to treat each of them. The consequences on LHC tungsten collimators of a number of beam abort scenarios were extensively studied, resorting to a novel category of numerical explicit methods, named Hydrocodes. Full shower simulations were performed providing the energy deposition distribution. Structural dynamics and shock wave propagation analyses were carried out with varying beam parameters, identifying important thresholds for collimator operation, ranging from the onset of permanent damage up to catastrophic failure. Since the main limitation of these tools lies in the limited information available on constitutive material models under extreme conditions, a dedica...

  14. Compact compressive arc and beam switchyard for energy recovery linac-driven ultraviolet free electron lasers

    Science.gov (United States)

    Akkermans, J. A. G.; Di Mitri, S.; Douglas, D.; Setija, I. D.

    2017-08-01

    High gain free electron lasers (FELs) driven by high repetition rate recirculating accelerators have received considerable attention in the scientific and industrial communities in recent years. Cost-performance optimization of such facilities encourages limiting machine size and complexity, and a compact machine can be realized by combining bending and bunch length compression during the last stage of recirculation, just before lasing. The impact of coherent synchrotron radiation (CSR) on electron beam quality during compression can, however, limit FEL output power. When methods to counteract CSR are implemented, appropriate beam diagnostics become critical to ensure that the target beam parameters are met before lasing, as well as to guarantee reliable, predictable performance and rapid machine setup and recovery. This article describes a beam line for bunch compression and recirculation, and beam switchyard accessing a diagnostic line for EUV lasing at 1 GeV beam energy. The footprint is modest, with 12 m compressive arc diameter and ˜20 m diagnostic line length. The design limits beam quality degradation due to CSR both in the compressor and in the switchyard. Advantages and drawbacks of two switchyard lines providing, respectively, off-line and on-line measurements are discussed. The entire design is scalable to different beam energies and charges.

  15. Attainment of Electron Beam Suitable for Medium Energy Electron Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Seletskiy, Sergei M. [Univ. of Rochester, NY (United States)

    2005-01-01

    Electron cooling of charged particle beams is a well-established technique at electron energies of up to 300 keV. However, up to the present time the advance of electron cooling to the MeV-range energies has remained a purely theoretical possibility. The electron cooling project at Fermilab has recently demonstrated the ¯rst cooling of 8.9 GeV/c antiprotons in the Recycler ring, and therefore, has proved the validity of the idea of relativistic electron cool- ing. The Recycler Electron Cooler (REC) is the key component of the Teva- tron Run II luminosity upgrade project. Its performance depends critically on the quality of electron beam. A stable electron beam of 4.3 MeV car- rying 0.5 A of DC current is required. The beam suitable for the Recycler Electron Cooler must have an angular spread not exceeding 200 ¹rad. The full-scale prototype of the REC was designed, built and tested at Fermilab in the Wideband laboratory to study the feasibility of attaining the high-quality electron beam. In this thesis I describe various aspects of development of the Fermilab electron cooling system, and the techniques used to obtain the electron beam suitable for the cooling process. In particular I emphasize those aspects of the work for which I was principally responsible.

  16. Measurements of photo-neutron energy spectra from thick targets produced by irradiation of 2.0 GeV electron beam

    International Nuclear Information System (INIS)

    Sato, Tatsuhiko; Shin, Kazuo; Yuasa, Ryuta; Ban, Syuichi; Lee, Heeseock

    2000-01-01

    Photo-neutron spectra produced by 2.04 GeV electron incident on thick Al, Cu, Sn and Pb targets were measured by TOF method. A Pb attenuator was placed at the middle point of the flight path to suppress γ-flash signals. The thickness of the attenuator was changed from 10 cm to 30 cm for each target, and the effects of the attenuator on the neutron spectra were calculated by a combination of small changed LAHET2.7 code and ENDF-HE/VI data. Obtained neutron spectra are larger than calculated values predicted by a combination of EGS4, our modified PICA95 and LAHET2.7 codes. (author)

  17. Determination of Endpoint Energy and Bremsstrahlung Spectra for High-Energy Radiation-Therapy Beams

    Science.gov (United States)

    Landry, Danny Joe

    Few attempts have been made to experimentally determine thick-target bremsstrahlung spectra of megavoltage therapy beams. For spectral studies using the Compton scattering technique, sodium iodine (NaI) detectors with relatively poor energy resolution have been used. Other experimental techniques for determining spectra are generally not suited for a clinical environment with the inherent time and space constraints. To gather more spectral information than previously obtained in the region near the endpoint energy, the use of a high-resolution intrinsic-germanium (Ge) detector was proposed. A response function matrix was determined from experimentally obtained pulse height distributions on the multichannel analyzer. The distributions were for nine various monoenergetic sources between 280 adn 1525 keV. The response function was used to convert the measured pulse height distributions to photon flux spectra using an iterative approximation technique with a computer. Photon flux spectra from the Sagittaire Linear Accelerator were obtained at average-electron endpoint energies of 15, 20, and 25 MeV. Two spectra were measured at the 25 MeV setting; one spectrum was measured along the central axis and one spectrum at 4(DEGREES) off axis. Photon spectra were also obtained for a Van de Graaff generator at the nominal endpoint energies of 2.2, 2.35, and 2.5 MeV. The results for both the linac and the Van de Graaff generator were compared with theoretical spectra and previously measured spectra where available. Also, photon spectra from a Theratron-80 (('60)Co) unit were determined for three field sizes and for a 10 x 10 cm. field with a lucite tray or a 45(DEGREES) wedge in the beam. The resulting spectra were compared to previously measured ('60)Co spectra.

  18. E-line: A new crystal collimator beam line for source size measurements at CHESS

    International Nuclear Information System (INIS)

    White, Jeffrey A.; Revesz, Peter; Finkelstein, Ken

    2007-01-01

    A new X-ray beam line has been constructed at cornell high energy synchrotron source (CHESS) to measure the vertical and horizontal source size of the positron particle beam. The cornell laboratory of elementary particle physics (LEPP) operates the storage ring (CESR) for X-ray generation for the CHESS user community by circulating electrons and their antimatter counterpart positrons in counter-rotating beams. As the laboratory reduces the emittances of particle beams to increase X-ray brilliance, there has been an increasing need for diagnostic tools to measure and monitor source size. A beam line front end that accesses the positron synchrotron light has been fitted with an experimental chamber and apparatus of compact design capable of horizontal and vertical source size measurement using the 'crystal collimator' technique, and an additional setup for vertical beam position monitoring using a luminescence-based X-ray video beam position monitoring system. The crystal collimators each consist of two Si(2 2 0) crystals in a dispersive (+,+) arrangement that diffract X-rays to a fluorescent material coated on a view port observed with a CCD camera. Measurements of the positron vertical beam size using the crystal collimation method at E-line are compared with measurements of visible synchrotron light at a remotely located dedicated port on the storage ring

  19. Measurement of the nTOF beam profile in the second experimental area (EAR2) using a silicon detector

    CERN Document Server

    Suljik, Fidan

    2017-01-01

    A new beam line and a second experimental area (EAR2) have been recently built at the neutron Time-Of-Flight (nTOF) facility at CERN. The characterization of the neutron beam in terms of spatial profile is a prerequisite for high accuracy cross-sections measurements. A silicon strip detector equipped with a neutron converter has been used to determine the beam profile as a function of incident neutron energy, in particular neutron beam profile has been measured from thermal energy up to 10 eV. Preliminary results have been compared with those collected with a MicroMegas detector also installed during the measurement.

  20. B-dot monitor for intense electron beam measurement

    International Nuclear Information System (INIS)

    Li Qin; Li Hong; Chen Nan; Gao Feng; Wang Yongwei; Wang Liping

    2009-01-01

    Azimuthal arrays of B-dot loops are often used to measure the time-resolved beam centroid position of a pulsed, intense electron beam propagating in a metallic tube. This paper describes the designing principle, parameters and calibration of the B-dot monitors. According to the beam current pulse rise time, fall time and the pulse width, the B-dot is designed to work as a differential loop, the loop inductance is about 60 nH. The B-dot monitor's sensitivity and the displacement curve are calibrated in the test stand. The sensitivity of the B-dots and the passive RC integrator is averagely 4 147 A/V, integrate constant is about 1 μs. The B-dot monitors are used to measure the Dragon-I electron beam and the experimental results show that the B-dot monitors can measure the beam current and centroid position accurately. (authors)

  1. Imprint reduction in rotating heavy ions beam energy deposition

    Energy Technology Data Exchange (ETDEWEB)

    Bret, A., E-mail: antoineclaude.bret@uclm.es [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS-51, Cambridge, MA 02138 (United States); ETSI Industriales, Universidad Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Piriz, A.R., E-mail: Roberto.Piriz@uclm.es [ETSI Industriales, Universidad Castilla-La Mancha, 13071 Ciudad Real (Spain); Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain); Tahir, N.A., E-mail: n.tahir@gsi.de [GSI Darmstadt, Plankstrasse 1, 64291 Darmstadt (Germany)

    2014-01-01

    The compression of a cylindrical target by a rotating heavy ions beam is contemplated in certain inertial fusion schemes or in heavy density matter experiments. Because the beam has its proper temporal profile, the energy deposition is asymmetric and leaves an imprint which can have important consequences for the rest of the process. In this paper, the Fourier components of the deposited ion density are computed exactly in terms of the beam temporal profile and its rotation frequency Ω. We show that for any beam profile of duration T, there exist an infinite number of values of ΩT canceling exactly any given harmonic. For the particular case of a parabolic profile, we find possible to cancel exactly the first harmonic and nearly cancel every other odd harmonics. In such case, the imprint amplitude is divided by 4 without any increase of Ω.

  2. Metastable atom probe for measuring electron beam density profiles

    Science.gov (United States)

    Lockhart, J. M.; Zorn, J. C.

    1972-01-01

    Metastable atom probe was developed for measuring current density in electron beam as function of two arbitrary coordinates, with spatial resolution better than 0.5 mm. Probe shows effects of space charge, magnetic fields, and other factors which influence electron current density, but operates with such low beam densities that introduced perturbation is very small.

  3. Laser Beam Caustic Measurement with Focal Spot Analyser

    DEFF Research Database (Denmark)

    Olsen, Flemming Ove; Gong, Hui; Bagger, Claus

    2005-01-01

    In industrial applications of high power CO2-lasers the caustic characteristics of the laser beam have great effects on the performance of the lasers. A welldefined high intense focused spot is essential for reliable production results. This paper presents a focal spot analyser that is developed...... for measuring the beam profiles of focused high power CO2-lasers....

  4. Beam Shaping for CARS Measurements in Turbulent Environments

    Science.gov (United States)

    Magnotti, Gaetano; Cutler, Andrew D.; Danehy, Paul M.

    2010-01-01

    This paper describes a new technique to mitigate the effect of beam steering on CARS measurements in turbulent, variable density environments. The new approach combines Planar BOXCARS phase-matching with elliptical shaping of one of the beams to generate a signal insensitive to beam steering, while keeping the same spatial resolution. Numerical and experimental results are provided to demonstrate the effectiveness of this approach. One set of experiments investigated the effect of beam shaping in the presence of a controlled and well quantified displacement of the beams at the focal plane. Another set of experiments, more qualitative, proved the effectiveness of the technique in the presence of severe beam steering due to turbulence.

  5. Automated translating beam profiler for in situ laser beam spot-size and focal position measurements

    Science.gov (United States)

    Keaveney, James

    2018-03-01

    We present a simple and convenient, high-resolution solution for automated laser-beam profiling with axial translation. The device is based on a Raspberry Pi computer, Pi Noir CMOS camera, stepper motor, and commercial translation stage. We also provide software to run the device. The CMOS sensor is sensitive over a large wavelength range between 300 and 1100 nm and can be translated over 25 mm along the beam axis. The sensor head can be reversed without changing its axial position, allowing for a quantitative estimate of beam overlap with counter-propagating laser beams. Although not limited to this application, the intended use for this device is the automated measurement of the focal position and spot-size of a Gaussian laser beam. We present example data of one such measurement to illustrate device performance.

  6. Energy Spread Reduction of Electron Beams Produced via Laser Wake

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, Bradley Bolt [Univ. of California, San Diego, CA (United States)

    2012-01-01

    Laser wakefield acceleration of electrons holds great promise for producing ultra-compact stages of GeV scale, high quality electron beams for applications such as x-ray free electron lasers and high energy colliders. Ultra-high intensity laser pulses can be self-guided by relativistic plasma waves over tens of vacuum diffraction lengths, to give >1 GeV energy in cm-scale low density plasma using ionization-induced injection to inject charge into the wake at low densities. This thesis describes a series of experiments which investigates the physics of LWFA in the self-guided blowout regime. Beginning with high density gas jet experiments the scaling of the LWFA-produced electron beam energy with plasma electron density is found to be in excellent agreement with both phenomenological theory and with 3-D PIC simulations. It is also determined that self-trapping of background electrons into the wake exhibits a threshold as a function of the electron density, and at the densities required to produce electron beams with energies exceeding 1 GeV a different mechanism is required to trap charge into low density wakes. By introducing small concentrations of high-Z gas to the nominal He background the ionization-induced injection mechanism is enabled. Electron trapping is observed at densities as low as 1.3 x 1018 cm-3 in a gas cell target, and 1.45 GeV electrons are demonstrated for the first time from LWFA. This is currently the highest electron energy ever produced from LWFA. The ionization-induced trapping mechanism is also shown to generate quasi-continuous electron beam energies, which is undesirable for accelerator applications. By limiting the region over which ionization-induced trapping occurs, the energy spread of the electron beams can be controlled. The development of a novel two-stage gas cell target provides the capability to tailor the gas composition in the longitudinal direction, and confine the trapping process to occur only in a

  7. First Measurement of Beam-Recoil Observables Cx and Cz

    Energy Technology Data Exchange (ETDEWEB)

    R. Bradford; R.A. Schumacher; G. Adams; M.J. Amaryan; P. Ambrozewicz; E. Anciant; M. Anghinolfi; B. Asavapibhop; G. Asryan; G. Audit; H. Avakian; H. Bagdasaryan; N. Baillie; J.P. Ball; N.A. Baltzell; S. Barrow; V. Batourine; M. Battaglieri; K. Beard; I. Bedlinskiy; M. Bektasoglu; M. Bellis; N. Benmouna; B.L. Berman; N. Bianchi; A.S. Biselli; B.E. Bonner; S. Bouchigny; S. Boiarinov; D. Branford; W.J. Briscoe; W.K. Brooks; S. B¨ultmann; V.D. Burkert; C. Butuceanu; J.R. Calarco; S.L. Careccia; D.S. Carman; B. Carnahan; S. Chen; P.L. Cole; A. Coleman; P. Collins; P. Coltharp; D. Cords; † P. Corvisiero; D. Crabb; H. Crannell; V. Crede; J.P. Cummings; R. De Masi; E. De Sanctis; R. De Vita; P.V. Degtyarenko; H. Denizli; L. Dennis; A. Deur; K.V. Dharmawardane; R. Dickson; C. Djalali; G.E. Dodge; J. Donnelly; D. Doughty; P. Dragovitsch; M. Dugger; S. Dytman; O.P. Dzyubak; H. Egiyan; ; K.S. Egiyan; L. El Fassi; L. Elouadrhiri; A. Empl; P. Eugenio; R. Fatemi; G. Fedotov; G. Feldman; R.J. Feuerbach; T.A. Forest; H. Funsten; M. Garcon; G. Gavalian; ; G.P. Gilfoyle; K.L. Giovanetti; F.X. Girod; J.T. Goetz; A. Gonenc; R.W. Gothe; K.A. Griffioen; M. Guidal; M. Guillo; N. Guler; L. Guo; V. Gyurjyan; C. Hadjidakis; K. Hafidi; H. Hakobyan; R.S. Hakobyan; J. Hardie; D. Heddle; F.W. Hersman; K. Hicks; I. Hleiqawi; M. Holtrop; J. Hu; M. Huertas; C.E. Hyde-Wright; Y. Ilieva; D.G. Ireland; B.S. Ishkhanov; E.L. Isupov; M.M. Ito; D. Jenkins; H.S. Jo; K. Joo; H.G. Juengst; N. Kalantarians; J.D. Kellie; M. Khandaker; K.Y. Kim; K. Kim; W. Kim; A. Klein; F.J. Klein; M. Klusman; M. Kossov; L.H. Kramer; V. Kubarovsky; J. Kuhn; S.E. Kuhn; S.V. Kuleshov; J. Lachniet; J.M. Laget; J. Langheinrich; D. Lawrence; A.C.S. Lima; K. Livingston; H.Y. Lu; K. Lukashin; M. MacCormick; J.J. Manak; C. Marchand; N. Markov; S. McAleer; B. McKinnon; J.W.C. McNabb; B.A. Mecking; M.D. Mestayer; C.A. Meyer; T. Mibe; K. Mikhailov; M. Mirazita; R. Miskimen; V. Mokeev; K. Moriya; S.A. Morrow; M. Moteabbed; V. Muccifora; J. Mueller; G.S. Mutchler; P. Nadel-Turonski; J. Napolitano; R. Nasseripour; N. Natasha; S. Niccolai; G. Niculescu; I. Niculescu; B.B. Niczyporuk; M.R. Niroula; R.A. Niyazov; M. Nozar; G.V. O’Rielly; M. Osipenko; A.I. Ostrovidov; K. Park; E. Pasyuk; C. Paterson; S.A. Philips; J. Pierce; N. Pivnyuk; D. Pocanic; O. Pogorelko; E. Polli; I. Popa; S. Pozdniakov; B.M. Preedom; J.W. Price; Y. Prok; D. Protopopescu; L.M. Qin; B.P. Quinn; B.A. Raue; G. Riccardi; G. Ricco; M. Ripani; B.G. Ritchie; F. Ronchetti; G. Rosner; P. Rossi; D. Rowntree; P.D. Rubin; F. Sabatie; J. Salamanca; C. Salgado; J.P. Santoro; ; V. Sapunenko; V.S. Serov; A. Shafi; Y.G. Sharabian; J. Shaw; N.V. Shvedunov; S. Simionatto; A.V. Skabelin; E.S. Smith; L.C. Smith; D.I. Sober; D. Sokhan; M. Spraker; A. Stavinsky; S.S. Stepanyan; S. Stepanyan; B.E. Stokes; P. Stoler; I.I. Strakovsky; S. Strauch; M. Taiuti; S. Taylor; D.J. Tedeschi; U. Thoma; R. Thompson; A. Tkabladze; S. Tkachenko; L. Todor; C. Tur; M. Ungaro; M.F. Vineyard; A.V. Vlassov; K. Wang; D.P. Watts; L.B. Weinstein; H. Weller; D.P. Weygand; M. Williams; E. Wolin; M.H. Wood; A. Yegneswaran; J. Yun; L. Zana; J. Zhang; B. Zhao; and Z.W. Zhao

    2007-03-01

    Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $\\vec\\gamma + p \\to K^+ + \\vec\\Lambda$ and $\\vec\\gamma + p \\to K^+ + \\vec\\Sigma^0$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $-0.85<\\cos\\theta_{K^+}^{c.m.}< +0.95$. For the $\\Lambda$, the polarization transfer coefficient along the photon momentum axis, $C_z$, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient, $C_x$, is smaller than $C_z$ by a roughly constant difference of unity. Most significantly, the {\\it total} $\\Lambda$ polarization vector, including the induced polarization $P$, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the $\\Sigma^0$ this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results.

  8. Measurements with radioactive beams at ATLAS.

    Energy Technology Data Exchange (ETDEWEB)

    Rehm, K. E.

    1998-08-06

    Reactions of interest to nuclear astrophysics have been studied with radioactive beams at the ATLAS accelerator. Using a modified ISOL technique, beams of {sup 18}F (T{sub 1/2} = 110 min) and {sup 56}Ni (T{sub 1/2} = 6.1d) were produced and the reactions {sup 18}F(p,{alpha}){sup 15}O, {sup 18}F(p,{gamma}){sup 19}Ne, and {sup 56}Ni(d,p){sup 57}Ni have been investigated. The results indicate that the {sup 18}F(p,{gamma}) route is a small contributor to the breakout from the hot CNO cycle into the rp process, while the {sup 56}Ni(p,{gamma}){sup 57}Cu rate is about ten times larger than previously assumed.

  9. Study on rice transformation mediated by low energy ion beam implantation

    International Nuclear Information System (INIS)

    Li Hong; Wu Lifang; Yu Zengliang

    2001-01-01

    Delivery of foreign DNA into rice via ion beam was first reported in 1994. In recent years we have aimed to set up efficient transformation system mediated by low energy ion beam. The factors that influence the transformation including type of ion, parameters of ion energy, dose and dose rate, plant genotype, composition of media, concentration of hormones and antibiotics were carefully investigated. Treated with 25ke V Ar + , the transformation efficiencies of the mature embryos of rice variety 02428, Hua pei94-jian-09 and Minghui63 reached 11%, 11.4% and 7.1% measured by produced antibiotic resistant callus and l.52%, 1.87% and l.13% measured by regenerated plants respectively. PCR detection and Southern blot analysis showed that GUS report gene had inserted in rice genome. Low energy ion beam mediated gene transfer will be extended to other cereal recalcitrant to Agrobacterium tumefaciens as soon as methodological parameters were optimized. (authors)

  10. Measurement system with high accuracy for laser beam quality.

    Science.gov (United States)

    Ke, Yi; Zeng, Ciling; Xie, Peiyuan; Jiang, Qingshan; Liang, Ke; Yang, Zhenyu; Zhao, Ming

    2015-05-20

    Presently, most of the laser beam quality measurement system collimates the optical path manually with low efficiency and low repeatability. To solve these problems, this paper proposed a new collimated method to improve the reliability and accuracy of the measurement results. The system accuracy controlled the position of the mirror to change laser beam propagation direction, which can realize the beam perpendicularly incident to the photosurface of camera. The experiment results show that the proposed system has good repeatability and the measuring deviation of M2 factor is less than 0.6%.

  11. Collective flow measurements at RHIC energies

    Directory of Open Access Journals (Sweden)

    Esumi Shinichi

    2017-01-01

    Full Text Available Recent experimental results on collective flow measurements from relativistic heavy-ion collider (RHIC are presented and discussed to study high-temperature and high-density quark-nuclear matter, Quark Gluon Plasma (QGP especially focusing on bulk properties, such as freeze-out parameters, temperature, chemical potential, collective expansion, azimuthal event anisotropy measurements. Their relations to the various correlation and fluctuation studies are also discussed, including initial geometrical and E- and B-field conditions as well as possible collective flow evolution that could even be developed in small systems. Current results and understandings from the beam energy scan program (BES and future plans are discussed and reviewed.

  12. Synchronization of streak and framing camera measurements of an intense relativistic electron beam propagating through gas

    International Nuclear Information System (INIS)

    Weidman, D.J.; Murphy, D.P.; Myers, M.C.; Meger, R.A.

    1994-01-01

    The expansion of the radius of a 5 MeV, 20 kA, 40 ns electron beam from SuperIBEX during propagation through gas is being measured. The beam is generated, conditions, equilibrated, and then passed through a thin foil that produces Cherenkov light, which is recorded by a streak camera. At a second location, the beam hits another Cherenkov emitter, which is viewed by a framing camera. Measurements at these two locations can provide a time-resolved measure of the beam expansion. The two measurements, however, must be synchronized with each other, because the beam radius is not constant throughout the pulse due to variations in beam current and energy. To correlate the timing of the two diagnostics, several shots have been taken with both diagnostics viewing Cherenkov light from the same foil. Experimental measurements of the Cherenkov light from one foil viewed by both diagnostics will be presented to demonstrate the feasibility of correlating the diagnostics with each other. Streak camera data showing the optical fiducial, as well as the final correlation of the two diagnostics, will also be presented. Preliminary beam radius measurements from Cherenkov light measured at two locations will be shown

  13. Pulse energy measurement at the SXR instrument

    International Nuclear Information System (INIS)

    Moeller, Stefan; Brown, Garth; Dakovski, Georgi; Hill, Bruce; Holmes, Michael; Loos, Jennifer; Maida, Ricardo; Paiser, Ernesto; Schlotter, William; Turner, Joshua J.; Wallace, Alex; Jastrow, Ulf; Kreis, Svea; Sorokin, Andrey A.; Tiedtke, Kai

    2015-01-01

    A gas monitor detector was implemented and characterized at the Soft X-ray Research instrument (SXR) to measure the average, absolute and pulse-resolved photon flux of the LCLS beam in the energy range between 280 and 2000 eV. A gas monitor detector was implemented and characterized at the Soft X-ray Research (SXR) instrument to measure the average, absolute and pulse-resolved photon flux of the LCLS beam in the energy range between 280 and 2000 eV. The detector is placed after the monochromator and addresses the need to provide reliable absolute pulse energy as well as pulse-resolved measurements for the various experiments at this instrument. This detector provides a reliable non-invasive measurement for determining flux levels on the samples in the downstream experimental chamber and for optimizing signal levels of secondary detectors and for the essential need of data normalization. The design, integration into the instrument and operation are described, and examples of its performance are given

  14. Measurement of electron beam bunch phase length by rectangular cavities

    International Nuclear Information System (INIS)

    Afanas'ev, V.D.; Rudychev, V.G.; Ushakov, V.I.

    1976-01-01

    An analysis of a phase length of electron bunches with the help of crossed rectangular resonators with the Hsub(102) oscillation type has been made. It has been shown that the electron coordinates after the duplex resonator are described by an ellipse equation for a non-modulated beam. An influence of the initial energy spread upon the electron motion has been studied. It has been ascertained that energy modulation of the electron beam results in displacement of each electron with respect to the ellipse which is proportional to modulation energy, i.e. an error in determination of the phase length of an electron bunch is proportional to the beam energy spread. Relations have been obtained which enable to find genuine values of phases of the analyzed electrons with an accuracy up to linear multipliers

  15. Measurements of the sensitivity of radiochromic film using ion beams

    Science.gov (United States)

    Steidle, J. A.; Shortino, J. P.; Ellison, D. M.; Freeman, C. G.; Sangster, T. C.

    2013-10-01

    Radiochromic film (RCF) is used in several diagnostics as a dosimeter that chromatically responds to incident particles. This response depends on the fluence, energy, and species of the incident particles. A 1.7 MV tandem Pelletron accelerator is used to create a monoenergetic ion beam which is scattered off a thin gold target onto a strip of RCF. A surface barrier detector is positioned behind a small hole in the film to measure the ion fluence on the nearby film. Once the film develops, it is scanned to examine its optical density. A response curve is acquired by fitting a three parameter formula to optical density and dose. These calibration curves can be used to help determine incident doses in a variety of situations.

  16. An optimized Faraday cage design for electron beam current measurements

    International Nuclear Information System (INIS)

    Turner, J.N.; Hausner, G.G.; Parsons, D.F.

    1975-01-01

    A Faraday cage detector is described for measuring electron beam intensity for use with energies up to 1.2 Mev, with the present data taken at 100 keV. The design features a readily changeable limiting aperture and detector cup geometry, and a secondary electron suppression grid. The detection efficiency of the cage is shown to be limited only by primary backscatter through the detector solid angle of escape, which is optimized with respect to primary backscattered electrons and secondary electron escape. The geometry and stopping material of the detection cup are varied, and the results show that for maximum detection efficiency with carbon as the stopping mateiral, the solid angle of escape must be equal to or less than 0.05πsr. The experimental results are consistent within the +-2% accuracy of the detection electronics, and are not limited by the Faraday cage detection efficiency. (author)

  17. Fiscal 1998 research report. Application technology of next-generation high-density energy beams; 1998 nendo chosa hokokusho. Jisedai komitsudo energy beam riyo gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Survey was made on application technologies of next- generation high-density energy beams. For real application of laser power, application to not exciting source of YAG crystal but machining directly is highly efficient. For generation of semiconductor laser high-power coherent beam, phase synchronization and summing are large technological walls. Short pulse, high intensity and high repeatability are also important. Since ultra-short pulse laser ends before heat transfer to the periphery, it is suitable for precise machining, in particular, ultra-fine machining. To use beam sources as tool for production process, development of transmission, focusing and control technologies, and optical fiber and device is indispensable. Applicable fields are as follows: machining (more than pico seconds), surface modification (modification and functionalization of tribo- materials and biocompatible materials), complex machining, fabrication of quantum functional structured materials (thin film, ultra-fine particle), agriculture, ultra-precise measurement, non-destructive measurement, and coherent chemistry in chemical and environment fields. (NEDO)

  18. Measuring Beam Quality of Hollow Core Photonic Crystal Fibers

    DEFF Research Database (Denmark)

    Shephard, J.D.; Roberts, John; Jones, J.D.C.

    2006-01-01

    In this paper, the authors measure the quality of the delivered beam from hollow core photonic crystal fibers (HC-PCFs). The$M^2$parameter is determined, and the near- to far-field transition is examined. The influence on these properties due to the presence of a core surround mode is evaluated....... The applicability of the International Standards Organization 11146 : 1999 standard for$M^2$measurement of the beam quality of HC-PCFs is discussed. Because they are dependent on the measurement parameters, such as choice of aperturing scheme and the axis of measurement,$M^2$values could vary from 1.32 to 3.......17 for the same output beam. This highlights the need for careful consideration when measuring and describing the beam quality delivered by these novel photonic fibers....

  19. Beam Optics Measurements Through Turn by Turn Beam Position Data in the SLS

    CERN Document Server

    Zisopoulos, P; Streun, A; Ziemann, v

    2013-01-01

    Refined Fourier analysis of turn-by-turn (TBT) transverse position data measurements can be used for determining several beam properties of a ring, such as transverse tunes, optics functions, phases, chromatic properties and coupling. In particular, the Numerical Analysis of Fundamental Frequencies (NAFF) algorithm is used to analyse TBT data from the Swiss Light Source (SLS) storage ring in order to estimate on and off-momentum beam characteristics. Of particular interest is the potential of using the full position information within one turn in order to measure beam optics properties.

  20. Measurement of the space potential of a high-temperature plasma by fast atomic beam scattering on an ion probe beam

    Energy Technology Data Exchange (ETDEWEB)

    Kabantsev, A. A.; Taskayev, S. Yu. [AN SSSR, Novosibirsk (USSR). Inst. Yadernoj Fiziki

    1988-06-01

    In this work we carry out an analysis of the possibility of measuring the potential distribution of a high-temperature plasma by scattering fast atoms on an ion probe beam. The proposed method is based on the idea of determining the energy of the ion beam, which depends on the plasma potential, from the energy spectrum of the scattered atoms. Application of this method allows one to avoid a number of fundamental difficulties characteristic of plasma potential measurements which make use of heavy-ion probe beams. 34 refs., 1 fig.

  1. Measurement of the space potential of a high-temperature plasma by fast atomic beam scattering on an ion probe beam

    International Nuclear Information System (INIS)

    Kabantsev, A.A.; Taskayev, S.Yu.

    1989-01-01

    In this work we carry out an analysis of the possibility of measuring the potential distribution of a high-temperature plasma by scattering fast atoms on an ion probe beam. The proposed method is based on the idea of determining the energy of the ion beam, which depends on the plasma potential, from the energy spectrum of the scattered atoms. Application of this method allows one to avoid a number of fundamental difficulties characteristic of plasma potential measurements which make use of heavy-ion probe beams. 34 refs., 1 fig

  2. Energy resolution methods efficiency depending on beam source ...

    Indian Academy of Sciences (India)

    2015-11-27

    Nov 27, 2015 ... Home; Journals; Pramana – Journal of Physics; Volume 69; Issue 3. Energy resolution methods efficiency depending on beam source position of potassium clusters in time-of-flight mass spectrometer. Ş Şentürk F Demiray O Özsoy. Research Articles Volume 69 Issue 3 September 2007 pp 459-465 ...

  3. MEIC Proton Beam Formation with a Low Energy Linac

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuhong [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    The MEIC proton and ion beams are generated, accumulated, accelerated and cooled in a new green-field ion injector complex designed specifically to support its high luminosity goal. This injector consists of sources, a linac and a small booster ring. In this paper we explore feasibility of a short ion linac that injects low-energy protons and ions into the booster ring.

  4. High energy physics with polarized beams and targets. [65 papers

    Energy Technology Data Exchange (ETDEWEB)

    Marshak, M L [ed.

    1976-01-01

    Sixty-six papers are presented as a report on conference sessions held from August 23-27, 1976, at Argonne National Laboratory. Topics covered include: (1) strong interactions; (2) weak and electromagnetic interactions; (3) polarized beams; and (4) polarized targets. A separate abstract was prepared for each paper for ERDA Energy Research Abstracts (ERA) and for the INIS Atomindex. (PMA)

  5. Solar Power Satellites: Creating the Market for Beamed Energy Propulsion

    International Nuclear Information System (INIS)

    Coopersmith, Jonathan

    2010-01-01

    Beamed energy advocates must investigate the potential of major markets like space based solar satellites and space-based nuclear waste disposal. For BEP to succeed, its proponents must work with these possible users to generate interest and resources needed to develop BEP.

  6. Beam lifetime measurement and analysis in Indus-2 electron ...

    Indian Academy of Sciences (India)

    injection septum, four injection kickers, four RF cavities and five insertion devices. Indus-2 synchrotron radiation facility consists of a pre-injector (microtron, which deliv- ers 20 MeV electron beam of 0.5 μs pulse width), an injector (booster synchrotron, which raises beam energy from 20 MeV to 550 MeV) and the storage ring ...

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

    International Nuclear Information System (INIS)

    Channell, P.J.

    1986-01-01

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

  8. Controlled Transverse Blow-up of Highenergy Proton Beams for Aperture Measurements and Loss Maps

    CERN Document Server

    Hӧfle, W; Redaelli, S; Schmidt, R; Valuch, D; Wollmann, D; Zerlauth, M

    2012-01-01

    A technique was developed to blow-up transversely in a controlled way high energy proton beams in the LHC. The technique is based on band limited white noise excitation that is injected into the transverse damper feedback loop. The injected signal can be gated to selectively blow-up individual trains of bunches. The speed of transverse blow-up can be precisely controlled. This opens the possibility to perform safely and efficiently aperture measurements and loss maps with high intensity bunch trains well above stored beam energies that are considered to be safe. In particular, lengthy procedures for measurements at top energy, otherwise requiring multiple fills of individual bunches, can be avoided. In this paper, the method is presented and results from beam measurements are discussed and compared with alternative blowup methods.

  9. Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

    International Nuclear Information System (INIS)

    Carnelli, P.F.F.; Almaraz-Calderon, S.; Rehm, K.E.; Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H.; Fernández Niello, J.; Henderson, D.; Jiang, C.L.; Lai, J.; Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C.; Paul, M.; Ugalde, C.

    2015-01-01

    A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the 10,13,15 C+ 12 C fusion reactions at energies around the Coulomb barrier

  10. Multi-Sampling Ionization Chamber (MUSIC) for measurements of fusion reactions with radioactive beams

    Energy Technology Data Exchange (ETDEWEB)

    Carnelli, P.F.F. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Científicas y Técnicas, Av. Rivadavia 1917, C1033AAJ Buenos Aires (Argentina); Almaraz-Calderon, S. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Rehm, K.E., E-mail: rehm@anl.gov [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Albers, M.; Alcorta, M.; Bertone, P.F.; Digiovine, B.; Esbensen, H. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Fernández Niello, J. [Laboratorio TANDAR, Comisión Nacional de Energía Atómica, Av. Gral. Paz 1499, B1650KNA, San Martín, Buenos Aires (Argentina); Universidad Nacional de San Martín, Campus Miguelete, B1650BWA San Martín, Buenos Aires (Argentina); Henderson, D.; Jiang, C.L. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Lai, J. [Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803 (United States); Marley, S.T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R.C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Paul, M. [Racah Institute of Physics, Hebrew University, Jerusalem (Israel); Ugalde, C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2015-11-01

    A detection technique for high-efficiency measurements of fusion reactions with low-intensity radioactive beams was developed. The technique is based on a Multi-Sampling Ionization Chamber (MUSIC) operating as an active target and detection system, where the ionization gas acts as both target and counting gas. In this way, we can sample an excitation function in an energy range determined by the gas pressure, without changing the beam energy. The detector provides internal normalization to the incident beam and drastically reduces the measuring time. In a first experiment we tested the performance of the technique by measuring the {sup 10,13,15}C+{sup 12}C fusion reactions at energies around the Coulomb barrier.

  11. Ion beam studies. Part 1. The retardation of ion beams to very low energies in an implantation accelerator

    International Nuclear Information System (INIS)

    Freeman, J.H.; Temple, W.; Beanland, D.; Gard, G.A.

    1976-02-01

    The design and operation of a compact electrostatic lens for the retardation and focussing of high intensity beams of heavy ions down to energies in the range 10 to 1,000 eV is described. The use of such beams for low-energy ion implantation and for the production of uniform ion-deposited layers is outlined. The practical behaviour of the lens is shown to be in agreement with computer calculations and the theoretical model is used to delineate and explain the boundary conditions under which the focussing behaviour becomes anomalous. The calculated and measured effects of space-charge repulsion on the quality of focussing are compared and it is demonstrated that a simple retardation lens design can be effectively employed at high flux. (author)

  12. Application of low energy electron beam to precoated steel plates

    International Nuclear Information System (INIS)

    Koshiishi, Kenji

    1989-01-01

    Recently in the fields of home electric appliances, machinery and equipment and interior building materials, the needs for the precoated steel plates having the design and function of high class increase rapidly. In order to cope with such needs, the authors have advanced the examination on the application of electron beam hardening technology to precoated steel plates, and developed the precoated steel plates of high grade and high design 'Super Tecstar EB Series' by utilizing low energy electron beam. The features of this process are (1) hardening can be done at room temperature in a short time-thermally weak films can be adhered, (2) high energy irradiation-the hardening of thick enamel coating and the adhesion of colored films are feasible, (3) the use of monomers of low molecular weight-by high crosslinking, the performance of high sharpness, high hardness, anti-contamination property and so on can be given. The application to precoated steel plate production process is the coating and curing of electron beam hardening type paints, the coating of films with electron beam hardening type adhesives, and the reforming of surface polymer layers by impregnating monomers and causing graft polymerization with electron beam irradiation. The outline of the Super Tecstar EB Series is described. (K.I.)

  13. Optics measurement and correction during beam acceleration in the Relativistic Heavy Ion Collider

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-09-09

    To minimize operational complexities, setup of collisions in high energy circular colliders typically involves acceleration with near constant β-functions followed by application of strong focusing quadrupoles at the interaction points (IPs) for the final beta-squeeze. At the Relativistic Heavy Ion Collider (RHIC) beam acceleration and optics squeeze are performed simultaneously. In the past, beam optics correction at RHIC has taken place at injection and at final energy with some interpolation of corrections into the acceleration cycle. Recent measurements of the beam optics during acceleration and squeeze have evidenced significant beta-beats which if corrected could minimize undesirable emittance dilutions and maximize the spin polarization of polarized proton beams by avoidance of higher-order multipole fields sampled by particles within the bunch. In this report the methodology now operational at RHIC for beam optics corrections during acceleration with simultaneous beta-squeeze will be presented together with measurements which conclusively demonstrate the superior beam control. As a valuable by-product, the corrections have minimized the beta-beat at the profile monitors so reducing the dominant error in and providing more precise measurements of the evolution of the beam emittances during acceleration.

  14. The determination of beam quality correction factors: Monte Carlo simulations and measurements.

    Science.gov (United States)

    González-Castaño, D M; Hartmann, G H; Sánchez-Doblado, F; Gómez, F; Kapsch, R-P; Pena, J; Capote, R

    2009-08-07

    Modern dosimetry protocols are based on the use of ionization chambers provided with a calibration factor in terms of absorbed dose to water. The basic formula to determine the absorbed dose at a user's beam contains the well-known beam quality correction factor that is required whenever the quality of radiation used at calibration differs from that of the user's radiation. The dosimetry protocols describe the whole ionization chamber calibration procedure and include tabulated beam quality correction factors which refer to 60Co gamma radiation used as calibration quality. They have been calculated for a series of ionization chambers and radiation qualities based on formulae, which are also described in the protocols. In the case of high-energy photon beams, the relative standard uncertainty of the beam quality correction factor is estimated to amount to 1%. In the present work, two alternative methods to determine beam quality correction factors are prescribed-Monte Carlo simulation using the EGSnrc system and an experimental method based on a comparison with a reference chamber. Both Monte Carlo calculations and ratio measurements were carried out for nine chambers at several radiation beams. Four chamber types are not included in the current dosimetry protocols. Beam quality corrections for the reference chamber at two beam qualities were also measured using a calorimeter at a PTB Primary Standards Dosimetry Laboratory. Good agreement between the Monte Carlo calculated (1% uncertainty) and measured (0.5% uncertainty) beam quality correction factors was obtained. Based on these results we propose that beam quality correction factors can be generated both by measurements and by the Monte Carlo simulations with an uncertainty at least comparable to that given in current dosimetry protocols.

  15. High energy density in matter produced by heavy ion beams

    International Nuclear Information System (INIS)

    1989-07-01

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

  16. Scenario for Precision Beam Energy Calibration in FCC-ee

    CERN Document Server

    Koop, I A

    2015-01-01

    The resonance depolarization method was very successfully used in the experiments at LEP, where the mass of the Z-boson was determined with the relative uncertainty [1, 2]. In the future FCC-ee circular electron-positron collider the luminosity at Z-peak (beam energy 45.5 GeV) is expected be 4-5 orders of magnitude higher and one goal is to perform the same experiments as at LEP, but with much greater accuracy, approaching the level of [3]. Obviously this can be done only by measuring the spin precession frequency. But there are many problems which still need to be solved on the way towards a complete design. The first one: the self-polarization takes too long a time. The Sokolov-Ternov polarization time is about 250 hours at Z-peak. One approach is to install the special field-asymmetric polarizing wigglers to make the self-polarization time much shorter [4, 5] and to utilize only few percent of the polarization degree to measure the resonance spin precession frequency. But these very strong wigglers substan...

  17. Combination of the H1 and ZEUS inclusive cross-section measurements at proton beam energies of 460 GeV and 575 GeV and tests of low Bjorken-x phenomenological models

    Energy Technology Data Exchange (ETDEWEB)

    Belov, Pavel

    2013-06-15

    A combination is presented of the inclusive neutral current e{sup {+-}}p scattering cross section data collected by the H1 and ZEUS collaborations during the last months of the HERA II operation period with proton beam energies E{sub p} of 460 and 575 GeV. The kinematic range of the cross section data covers low absolute four-momentum transfers squared, 1.5 GeV{sup 2} {<=} Q{sup 2} {<=} 110 GeV{sup 2}, small values of Bjorken-x, 2.8.10{sup -5} {<=} x {<=} 1.5.10{sup -2}, and high inelasticity y {<=} 0.85. The combination algorithm is based on the method of least squares and takes into account correlations of the systematic uncertainties. The combined data are used in the QCD fits to extract the parton distribution functions. The phenomenological low-x dipole models are tested and parameters of the models are obtained. A good description of the data by the dipole model taking into account the evolution of the gluon distribution is observed. The longitudinal structure function F{sub L} is extracted from the combination of the currently used H1 and ZEUS reduced proton beam energy data with previously published H1 nominal proton beam energy data of 920 GeV. A precision of the obtained values of F{sub L} is improved at medium Q{sup 2} compared to the published results of the H1 collaboration.

  18. Low energy electron beams for industrial and environmental applications

    CERN Document Server

    Skarda, Vlad

    2017-01-01

    EuCARD-2 Workshop, 8-9 December 2016, Warsaw, Poland. Organizers: Science and Technology Facilities Council, UK CERN - The European Organization for Nuclear Research, Switzerland, Institute of Nuclear Chemistry and Technology, Poland, Fraunhofer Institute for Electron Beam and Plasma Technology, Germany, Warsaw University of Technology, Poland. An article presents short information about EuCARD-2 Workshop “Low energy electron beams for industrial and environmental applications”, which was held in December 2016 in Warsaw. Objectives, main topics and expected output of meeting are described. List of organizers is included.

  19. Funneling study with a low energy proton beam

    International Nuclear Information System (INIS)

    Barth, W.; Schempp, A.

    1991-01-01

    Funneling is a method to increase the brightness of ion beams by filling all rf-buckets in order to use the full current transport capability of an rf accelerator by frequency jumps at higher energies. This has been proposed for HIIF type drivers and neutron sources. A simple funneling experiment is prepared at Frankfurt, using modest fields in a set up with a 50 keV proton beam and an rf deflector to study especially emittance growth effects in such funneling lines. First results will be reported

  20. Desain Cantilever Beam Piezoelectric Untuk Aplikasi Energi Harvesting

    Directory of Open Access Journals (Sweden)

    Roer Pawinanto

    2016-12-01

    Full Text Available Material piezoelektrik sudah mulai diaplkasikan dalam beberapa aplikasi seperti sebagai transduser untuk energi harvesting. Dalam studi ini kami menggunakan metode FEA untuk mengoptimasi beam piezoelektrik. Defleksi yang diperoleh pada studi ini yaitu sebesar 83 nm manakala frekuensi resonansi nya diperoleh di 13.4 Hz. Material piezoelektrik ini dapat menghasilkan defleksi yang besar ketika bergetar pada frekuensi resonansinya. Hasil optimisasi juga menunjukkan bahwa daya listrik yang dihasilkan mengindikasikan resistansi yang besar juga dan berkaitan dengan panjang material PZT serta dapat mempengaruhi defleksi dari cantilever beam.

  1. Sterilization of experimental animal feeds with high energy electron beam

    International Nuclear Information System (INIS)

    Takekawa, Tetsuya; Shakudo, Taketomi; Furuta, Masakazu; Tada, Mikiro

    2005-01-01

    Penetration range and depth-dose distribution of 10 MeV electrons within commercial packages of experimental animal feeds were examined with a high power electron accelerator for verification of the application of high energy electron beam irradiation to sterilize experimental animal feeds. Optimum packaging sizes were proposed based on the experimental results. The change of the vitamins and the efficacy of the sterilization by the irradiation were also studied. It is confirmed that the sterilization of experimental animal feeds by 10 MeV electron beam has been completely practical. (author)

  2. Production of intermediate energy beams by high speed rotors

    International Nuclear Information System (INIS)

    Nutt, C.W.; Bale, T.J.; Cosgrove, P.; Kirby, M.J.

    1975-01-01

    A rotor apparatus intended for the study of gas/surface interaction processes is presently nearing completion. The carbon fiber rotors under consideration are constructed with shapes derived from long thin cylindrical rods oriented with the longest axis in a horizontal plane, and spun in a horizontal plane about an axis which is perpendicular to the long axis and passes through the mid-point of the cylinder. The beam formation processes are discussed and rotor diagrams presented. Performance of these types of high speed rotor show them to have a very important future as sources of intermediate energy molecular beams

  3. Two-Screen Method for Determining Electron Beam Energy and Deflection from Laser Wakefield Acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Pollock, B B; Ross, J S; Tynan, G R; Divol, L; Glenzer, S H; Leurent, V; Palastro, J P; Ralph, J E; Froula, D H; Clayton, C E; Marsh, K A; Pak, A E; Wang, T L; Joshi, C

    2009-04-24

    Laser Wakefield Acceleration (LWFA) experiments have been performed at the Jupiter Laser Facility, Lawrence Livermore National Laboratory. In order to unambiguously determine the output electron beam energy and deflection angle at the plasma exit, we have implemented a two-screen electron spectrometer. This system is comprised of a dipole magnet followed by two image plates. By measuring the electron beam deviation from the laser axis on each plate, both the energy and deflection angle at the plasma exit are determined through the relativistic equation of motion.

  4. An energy-based beam hardening model in tomography

    Energy Technology Data Exchange (ETDEWEB)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E [Vision Lab, Physics Departement, University of Antwerp (RUCA) (Belgium)

    2002-12-07

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography ({mu}CT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages.

  5. Beam Diagnostics for the BNL Energy Recovery Linac Test Facility

    International Nuclear Information System (INIS)

    Cameron, Peter; Ben-Zvi, Ilan; Blaskiewicz, Michael; Brennan, Michael; Connolly, Roger; Dawson, William; Degen, Chris; DellaPenna, Al; Gassner, David; Kesselman, Martin; Kewish, Jorg; Litvinenko, Vladimir; Mead, Joseph; Oerter, Brian; Russo, Tom; Vetter, Kurt; Yakimenko, Vitaly

    2004-01-01

    An Energy Recovery Linac (ERL) test facility is presently under construction at BNL. The goals of this test facility are first to demonstrate stable intense CW electron beam with parameters typical for the RHIC e-cooling project (and potentially for eRHIC), second to test novel elements of the ERL (high current CW photo-cathode, superconducting RF cavity with HOM dampers, and feedback systems), and finally to test lattice dependence of stability criteria. Planned diagnostics include position monitors, loss monitors, transverse profile monitors (both optical and wires), scrapers/halo monitors, a high resolution differential current monitor, phase monitors, an energy spread monitor, and a fast transverse monitor (for beam break-up studies and the energy feedback system). We discuss diagnostics challenges that are unique to this project, and present preliminary system specifications. In addition, we include a brief discussion of the timing system

  6. An energy-based beam hardening model in tomography

    International Nuclear Information System (INIS)

    Casteele, E van de; Dyck, D van; Sijbers, J; Raman, E

    2002-01-01

    As a consequence of the polychromatic x-ray source, used in micro-computer tomography (μCT) and in medical CT, the attenuation is no longer a linear function of absorber thickness. If this nonlinear beam hardening effect is not compensated, the reconstructed images will be corrupted by cupping artefacts. In this paper, a bimodal energy model for the detected energy spectrum is presented, which can be used for reduction of artefacts caused by beam hardening in well-specified conditions. Based on the combination of the spectrum of the source and the detector efficiency, the assumption is made that there are two dominant energies which can describe the system. The validity of the proposed model is examined by fitting the model to the experimental datapoints obtained on a microtomograph for different materials and source voltages

  7. Intermediate-energy neutron beam for NCT at MURR

    International Nuclear Information System (INIS)

    Brugger, R.M.; Less, T.J.; Passmore, G.G.

    1986-01-01

    The University of Missouri Research Reactor (MURR) is one of the high-flux reactors in the USA and it can be used to produce an intense beam of intermediate-energy neutrons for neutron capture therapy. Two methods are being evaluated at MURR to produce such a beam. The first uses a moderator of Al 2 O 3 replacing part of the graphite and water on one side of the core of the reactor to produce a source of predominantly intermediate-energy neutrons. The second method is a filter of 238 U between the core and the patient position to pass only intermediate-energy neutrons. The results of these evaluations are presented in this paper along with an outline of the other resources at the University of Missouri-Columbia that are available to support an NCT program. 4 references, 7 figures, 1 table

  8. A Beam Interlock System for CERN High Energy Accelerators

    CERN Document Server

    Todd, Benjamin; Schmidt, R

    2006-01-01

    The Large Hadron Collider (LHC) at CERN (The European Organisation for Nuclear Research) is one of the largest and most complicated machines envisaged to date. The LHC has been conceived and designed over the course of the last 25 years and represents the cutting edge of accelerator technology with a collision energy of 14TeV, having a stored beam energy over 100 times more powerful than the nearest competitor. Commissioning of the machine is already nderway and operation with beam is intended for Autumn 2007, with 7TeV operation expected in 2008. The LHC is set to answer some of the fundemental questions in theoretical physics, colliding particles with such high energy that the inner workings of the quantum world can be revealed. Colliding particles together at such high energy makes very high demands on machine operation and protection. The specified beam energy requires strong magnetic fields that are made in superconducting dipole magnets, these magnets are kept only around two degrees above absolute zero...

  9. Measurement of secondary radiation during ion beam therapy with the pixel detector Timepix

    Science.gov (United States)

    Martišíková, Mária; Jakubek, Jan; Granja, Carlos; Hartmann, Bernadette; Opálka, Lukáš; Pospíšil, Stanislav; Jäkel, Oliver

    2011-11-01

    In ion beam therapy the finite range of the ion beams in tissue and the presence of the Bragg-peak are exploited. Unpredictable changes in the patient`s condition can alter the range of the ion beam in the body. Therefore it is desired to verify the actual ion range during the treatment, preferably in a non-invasive way. Positron emission tomography (PET) has been used successfully to monitor the applied dose distributions. This method however suffers from limited applicability and low detection efficiency. In order to increase the detection efficiency and to decrease the uncertainties, in this study we investigate the possibility to measure secondary charged particles emerging from the patient during irradiation. An initial experimental study to register the particle radiation coming out of a patient phantom during the therapy was performed at the Heidelberg Ion Beam Therapy Center (HIT) in Germany. A static narrowly-focused beam of carbon ions was directed into a head phantom. The emerging secondary radiation was measured with the position-sensitive Timepix detector outside of the phantom. The detector, developed by the Medipix Collaboration, consists of a silicon sensor bump bonded to a pixelated readout chip (256 × 256 pixels with 55 μm pitch). Together with the USB-based readout interface, Timepix can operate as an active nuclear emulsion registering single particles online with 2D-track visualization. In this contribution we measured the signal behind the head phantom and investigated its dependence on the beam energy (corresponding to beam range in water 2-30 cm). Furthermore, the response was measured at four angles between 0 and 90 degrees. At all investigated energies some signal was registered. Its pattern corresponds to ions. Differences in the total amount of signal for different beam energies were observed. The time-structure of the signal is correlated with that of the incoming beam, showing that we register products of prompt processes. Such

  10. Measurement of secondary radiation during ion beam therapy with the pixel detector Timepix

    International Nuclear Information System (INIS)

    Martišíková, Mária; Hartmann, Bernadette; Jäkel, Oliver; Jakubek, Jan; Granja, Carlos; Opálka, Lukáš; Pospíšil, Stanislav

    2011-01-01

    In ion beam therapy the finite range of the ion beams in tissue and the presence of the Bragg-peak are exploited. Unpredictable changes in the patient's condition can alter the range of the ion beam in the body. Therefore it is desired to verify the actual ion range during the treatment, preferably in a non-invasive way. Positron emission tomography (PET) has been used successfully to monitor the applied dose distributions. This method however suffers from limited applicability and low detection efficiency. In order to increase the detection efficiency and to decrease the uncertainties, in this study we investigate the possibility to measure secondary charged particles emerging from the patient during irradiation. An initial experimental study to register the particle radiation coming out of a patient phantom during the therapy was performed at the Heidelberg Ion Beam Therapy Center (HIT) in Germany. A static narrowly-focused beam of carbon ions was directed into a head phantom. The emerging secondary radiation was measured with the position-sensitive Timepix detector outside of the phantom. The detector, developed by the Medipix Collaboration, consists of a silicon sensor bump bonded to a pixelated readout chip (256 × 256 pixels with 55 μm pitch). Together with the USB-based readout interface, Timepix can operate as an active nuclear emulsion registering single particles online with 2D-track visualization. In this contribution we measured the signal behind the head phantom and investigated its dependence on the beam energy (corresponding to beam range in water 2–30 cm). Furthermore, the response was measured at four angles between 0 and 90 degrees. At all investigated energies some signal was registered. Its pattern corresponds to ions. Differences in the total amount of signal for different beam energies were observed. The time-structure of the signal is correlated with that of the incoming beam, showing that we register products of prompt processes. Such

  11. Direct-current proton-beam measurements at Los Alamos

    International Nuclear Information System (INIS)

    Sherman, J.; Stevens, R.R.; Schneider, J.D.; Zaugg, T.

    1994-01-01

    Recently, a CW proton accelerator complex was moved from Chalk River Laboratories (CRL) to Los Alamos National Laboratory. This includes a 50-keV dc proton injector with a single-solenoid low-energy beam transport system (LEBT) and a CW 1.25-MeV, 267-MHz radiofrequency quadrupole (RFQ). The move was completed after CRL had achieved 55-mA CW operation at 1.25 MeV using 250-kW klystrode tubes to power the RFQ. These accelerator components are prototypes for the front end of a CW linac required for an accelerator-driven transmutation linac, and they provide early confirmation of some CW accelerator components. The injector (ion source and LEBT) and emittance measuring unit are installed and operational at Los Alamos. The dc microwave ion source has been operated routinely at 50-keV, 75-mA hydrogen-ion current. This ion source has demonstrated very good discharge and H 2 gas efficiencies, and sufficient reliability to complete CW RFQ measurements at CRL. Proton fraction of 75% has been measured with 550-W discharge power. This high proton fraction removes the need for an analyzing magnet. Proton LEBT emittance measurements completed at Los Alamos suggest that improved transmission through the RFQ may be achieved by increasing the solenoid focusing current. Status of the final CW RFQ operation at CRL and the installation of the RFQ at Los Alamos is given

  12. Application of virtual instrument in accelerator beam measurement system

    International Nuclear Information System (INIS)

    Huang Guoqing; China Science and Technology Univ., Hefei; Yu Xiaoqi; Zhang Pengfei

    2007-01-01

    Virtual instrument is a novel computer-based technical method of measurement, which has got rapidly development and has been applied in many fields because of a variety of advantages. In this paper we mainly introduce application of virtual instrument in accelerator beam measurement system. Beam measurement system is an important part of accelerator technology and has important effect on accelerator debugging, running and machine research. Adopting new measurement methods and increasing accuracy of measurement directly affect accelerator debugging and running. Now many accelerators have been adopted virtual instrument system. (authors)

  13. Simulation and Measurements of Beam Losses on LHC Collimators During Beam Abort Failures

    CERN Document Server

    Lari, L; Bruce, R; Goddard, B; Redaelli, S; Salvachua, B; Valentino, G; Faus-Golfe, A

    2013-01-01

    One of the main purposes of tracking simulations for collimation studies is to produce loss maps along the LHC ring, in order to identify the level of local beam losses during nominal and abnormal operation scenarios. The SixTrack program is the standard tracking tool used at CERN to perform these studies. Recently, it was expanded in order to evaluate the proton load on different collimators in case of fast beam failures. Simulations are compared with beam measurements at 4 TeV. Combined failures are assumed which provide worst-case scenarios of the load on tungsten tertiary collimators.

  14. System Architecture for measuring and monitoring Beam Losses in the Injector Complex at CERN

    CERN Document Server

    Zamantzas, C; Dehning, B; Jackson, S; Kwiatkowski, M; Vigano, W

    2012-01-01

    The strategy for beam setup and machine protection of the accelerators at the European Organisation for Nuclear Research (CERN) is mainly based on its Beam Loss Monitoring (BLM) systems. For their upgrade to higher beam energies and intensities, a new BLM system is under development with the aim of providing faster measurement updates with higher dynamic range and the ability to accept more types of detectors as input compared to its predecessors. In this paper, the architecture of the complete system is explored giving an insight to the design choices made to provide a highly reconfigurable system that is able to fulfil the different requirements of each accelerator using reprogrammable devices.

  15. A two-beam radio-frequency quadrupole (RFQ) for funnelling of ion beams at low energies

    International Nuclear Information System (INIS)

    Firjahn-Andersch, A.; Schempp, A.; Madlung, J.; Staschok, C.

    1996-01-01

    In a heavy ion inertial fusion river the strongest current limitations are space charge forces in the low energy part of the linac. For this reason the required high current and small emittance ion beam will be reached by several funnelling stages where two identically bunched ion beams are combined into a single beam with twice the frequency, current and brightness. For the first funnelling stage a new two-beam radio-frequency quadrupolecould be used where two beams are bunched and accelerated in a single RF cavity. The RF structure development and the experimental set-up for beam funnelling with He + will be presented. (orig.)

  16. Laser alignment measurement model with double beam

    Science.gov (United States)

    Mo, Changtao; Zhang, Lili; Hou, Xianglin; Wang, Ming; Lv, Jia; Du, Xin; He, Ping

    2012-10-01

    Double LD-Double PSD schedule.employ a symmetric structure and there are a laser and a PSD receiver on each axis. The Double LD-Double PSD is used, and the rectangular coordinate system is set up by use of the relationship of arbitrary two points coordinates, and then the parameter formula is deduced by the knowledge of solid geometry. Using the data acquisition system and the data processing model of laser alignment meter with double laser beam and two detector , basing on the installation parameter of the computer, we can have the state parameter between the two shafts by more complicated calculation and correction. The correcting data of the four under chassis of the adjusted apparatus moving on the level and the vertical plane can be calculated using the computer. This will instruct us to move the apparatus to align the shafts.

  17. Parallel beam scanning system for flatness measurements of thin plates

    Science.gov (United States)

    Fan, Kuang-Chao; Wu, John H.

    1993-09-01

    This paper describes the work to develop a Parallel Beam Scanning System (PBSS) for the non-contact measurement of surface flatness of thin plates. The PBSS consists of a He-Ne laser source having good pointing stability a scanner to create divergent scanning beams a large aplanatic meniscus lens to convert the divergent beams to parallel beams a linear stage to drive the testpiece to each sampling position a screen for the projection of reflected beams from the tested surface and an image processing unit to analyze the projected image. Due to the out-of-flatness of the surface the straight line formed by the incident parallel beams will be distorted and magnified on the screen as it is reflected from the tested surface. The stage then positions the testpiece step-by-step to carry out measurements in the line-by-line sequence. A CCD camera is employed to capture the image of the distorted line on the screen each time. With the proposed mathematical model the flatness data of the testpiece can be computed from the input image data. Experimental results by the use of this system have shown in good agreement with the results obtained from the coordinate measuring machine. This system can be applied to the flatness measurements of thin plates such as sheet metals sheet moulding compound (SMC) plates glass plates etc. which are difficult to measure by traditional methods.

  18. Effect of ion beam energy on density, roughness & uniformity of Co film deposited using ion beam sputtering system

    Science.gov (United States)

    Dhawan, Rajnish; Rai, Sanjay; Lodha, G. S.

    2012-06-01

    Cobalt (Co) films were prepared, using ion beam sputtering technique. Films were prepared by varying beam voltage from 700 to 1100 V at room temperature. The influence of ion beam energy on the density, surface roughness and thickness uniformity of Co film was investigated. X-ray reflectivity study shows that surface roughness of film decreases with increasing beam energy and lowest surface roughness of 1.3 Å was achieved for 1000 V beam voltage at 4 cm3/min Ar gas flow. The density of the film was 93% of bulk density of Co. These ultra low roughness films are very promising for studying the magnetic properties of Co films.

  19. High-energy tritium beams as current drivers in tokamak reactors

    International Nuclear Information System (INIS)

    Mikkelsen, D.R.; Grisham, L.R.

    1983-04-01

    The effect on neutral-beam design and reactor performance of using high-energy (approx. 3-10 MeV) tritium neutral beams to drive steady-state tokamak reactors is considered. The lower current of such beams leads to several advantages over lower-energy neutral beams. The major disadvantage is the reduction of the reactor output caused by the lower current-drive efficiency of the high-energy beams

  20. A high energy neutral beam system for reactors

    International Nuclear Information System (INIS)

    Anderson, O.A.; Chan, C.F.; Cooper, W.S.

    1988-09-01

    High energy neutral beams provide a promising method of heating and driving current in steady-state tokamak fusion reactors. As an example, we have made a conceptual design of a neutral beam system for current drive on the International Thermonuclear Experimental Reactor (ITER). The system, based on electrostatic acceleration of D/sup /minus// ions, can deliver up to 100 MW of 1.6 MeV D 0 neutrals through three ports. Radiation protection is provided by locating sensitive beamline components 35 to 50 m from the reactor. In an application to a 3300 MW power reactor, a system delivering 120 MW of 2-2.4 MeV deuterium beams assisted by 21 MW of lower hybrid wave power drives 25 MA and provides an adequate plasma power gain (Q = 24) for a commercial fusion power plant. 8 refs., 1 fig., 2 tabs

  1. Penetration of an electron beam into material and energy dissipation

    International Nuclear Information System (INIS)

    Kral, V.; Pelzbauer, Z.

    1986-01-01

    The contribution is concerned with penetration of an electron beam having energy between 5 and 25 keV into the polymer and with energy dissipation inside the interaction volume of the polymer. The experimentally observed shape on the interaction volume has been theoretically substantiated, the range has been calculated, and a comparison with Gruen's empirical relation has been carried out. It is shown that with increasing accelerating voltage the centre of the core of the interaction volume is shifted more deeply under the sample surface and the dissipated energy decreases. Extension of the neck of the interaction volume caused by back scattering is discussed. (author)

  2. Radiation effect of low energy electron beam on plant growth

    International Nuclear Information System (INIS)

    Takeshita, Hidefumi; Yoshii, Fumio; Kume, Tamikazu

    2000-01-01

    Radiation effect of low energy electron beam (EB) on the growth of maize, barley and soybean was investigated. Seeds of maize, barley and soybean were irradiated in the dose range of 2 to 20 kGy using EB with different energy from 150 to 250 keV. Growth promotion was observed for irradiated seeds of maize and soybean at the dose up to 10 kGy. Especially, significant promotion of root growth was observed for irradiated barley and soybean. It was also found for soybean that phytoalexin induction activity was clearly enhanced by low energy EB irradiation. (author)

  3. High energy gain electron beam acceleration by 100TW laser

    International Nuclear Information System (INIS)

    Kotaki, Hideyuki; Kando, Masaki; Kondo, Shuji; Hosokai, Tomonao; Kanazawa, Shuhei; Yokoyama, Takashi; Matoba, Toru; Nakajima, Kazuhisa

    2001-01-01

    A laser wakefield acceleration experiment using a 100TW laser is planed at JAERI-Kansai. High quality and short pulse electron beams are necessary to accelerate the electron beam by the laser. Electron beam - laser synchronization is also necessary. A microtron with a photocathode rf-gun was prepared as a high quality electron injector. The quantum efficiency (QE) of the photocathode of 2x10 -5 was obtained. A charge of 100pC from the microtron was measured. The emittance and pulse width of the electron beam was 6π mm-mrad and 10ps, respectively. In order to produce a short pulse electron beam, and to synchronize between the electron beam and the laser pulse, an inverse free electron laser (IFEL) is planned. One of problems of LWFA is the short acceleration length. In order to overcome the problem, a Z-pinch plasma waveguide will be prepared as a laser wakefield acceleration tube for 1 GeV acceleration. (author)

  4. Measurement and simulation of the TRR BNCT beam parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bavarnegin, Elham [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Department of Physics, University of Guilan, Rasht (Iran, Islamic Republic of); Sadremomtaz, Alireza [Department of Physics, University of Guilan, Rasht (Iran, Islamic Republic of); Khalafi, Hossein [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Kasesaz, Yaser, E-mail: ykasesaz@aeoi.org.ir [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Golshanian, Mohadeseh; Ghods, Hossein; Ezzati, Arsalan; Keyvani, Mehdi; Haddadi, Mohammad [Nuclear Science and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of)

    2016-09-11

    Recently, the configuration of the Tehran Research Reactor (TRR) thermal column has been modified and a proper thermal neutron beam for preclinical Boron Neutron Capture Therapy (BNCT) has been obtained. In this study, simulations and experimental measurements have been carried out to identify the BNCT beam parameters including the beam uniformity, the distribution of the thermal neutron dose, boron dose, gamma dose in a phantom and also the Therapeutic Gain (TG). To do this, the entire TRR structure including the reactor core, pool, the thermal column and beam tubes have been modeled using MCNPX Monte Carlo code. To measure in-phantom dose distribution a special head phantom has been constructed and foil activation techniques and TLD700 dosimeter have been used. The results show that there is enough uniformity in TRR thermal BNCT beam. TG parameter has the maximum value of 5.7 at the depth of 1 cm from the surface of the phantom, confirming that TRR thermal neutron beam has potential for being used in treatment of superficial brain tumors. For the purpose of a clinical trial, more modifications need to be done at the reactor, as, for example design, and construction of a treatment room at the beam exit which is our plan for future. To date, this beam is usable for biological studies and animal trials. There is a relatively good agreement between simulation and measurement especially within a diameter of 10 cm which is the dimension of usual BNCT beam ports. This relatively good agreement enables a more precise prediction of the irradiation conditions needed for future experiments.

  5. Influence of Polarization of the Incident Beam on Integrated Intensities in X-Ray Energy-Dispersive Diffractometry

    DEFF Research Database (Denmark)

    Olsen, J. Staun; Buras, B.; Jensen, T.

    1978-01-01

    Polarization measurements of the primary X-ray beam produced by thick copper and tungsten anodes are reported and formulas derived for integrated intensities of Bragg reflections in energy-dispersive diffractometry with the polarization of the primary beam taken into account. It was found...

  6. Tomographic measurement of the phase space distribution of a space-charge-dominated beam

    Science.gov (United States)

    Stratakis, Diktys

    Many applications of accelerators, such as free electron lasers, pulsed neutron sources, and heavy ion fusion, require a good quality beam with high intensity. In practice, the achievable intensity is often limited by the dynamics at the low-energy, space-charge dominated end of the machine. Because low-energy beams can have complex distribution functions, a good understanding of their detailed evolution is needed. To address this issue, we have developed a simple and accurate tomographic method to map the beam phase using quadrupole magnets, which includes the effects from space charge. We extend this technique to use also solenoidal magnets which are commonly used at low energies, especially in photoinjectors, thus making the diagnostic applicable to most machines. We simulate our technique using a particle in cell code (PIC), to ascertain accuracy of the reconstruction. Using this diagnostic we report a number of experiments to study and optimize injection, transport and acceleration of intense space charge dominated beams. We examine phase mixing, by studying the phase-space evolution of an intense beam with a transversely nonuniform initial density distribution. Experimental measurements, theoretical predictions and PIC simulations are in good agreement each other. Finally, we generate a parabolic beam pulse to model those beams from photoinjectors, and combine tomography with fast imaging techniques to investigate the time-sliced parameters of beam current, size, energy spread and transverse emittance. We found significant differences between the slice emittance profiles and slice orientation as the beam propagates downstream. The combined effect of longitudinal nonuniform profiles and fast imaging of the transverse phase space provided us with information about correlations between longitudinal and transverse dynamics that we report within this dissertation.

  7. High energy beam line based on bent crystal

    International Nuclear Information System (INIS)

    Biryukov, V.M.; Chesnokov, Yu.A.; Greth, V.N.; Ivanov, A.A.; Kotov, V.I.; Selesnev, V.S.; Tarakanov, M.V.; Terekhov, V.I.; Tsarik, S.V.

    1995-01-01

    A peculiarities of the beam bent with crystals is the independence of the crystal deflector strength Θ=L D /R c ∼0.5 rad of the particle energy (L D is the dechanneling length, R c is the critical radius). The possibility of abrupt bending with crystal of a beam fraction at a large angle allows one to make over a short base a non-traditional beam line to carry out physical experiments. At IHEP, a 150 mrad bent crystal was used to create a test area, to work in parallel with other set-ups consuming practically no power. A 100 mm long Si crystal, placed in the halo of the intense extracted 70 GeV/c beam, extracts along the ∼20 m base 10 6 protons/sec beyond the 2-meter iron-concrete shield. The beam high quality (low emittance and high stability) allows one to carry out the program of the studies of channeling and testing the microstrip detectors. 2 refs.; 2 figs

  8. Determining clinical photon beam spectra from measured depth dose with the Cimmino algorithm

    International Nuclear Information System (INIS)

    Bloch, P.; Altschuler, M.D.; Bjaerngard, B.E.; Kassaee, A.; McDonough, J.

    2000-01-01

    A method to determine the spectrum of a clinical photon beam from measured depth-dose data is described. At shallow depths, where the range of Compton-generated electrons increases rapidly with photon energy, the depth dose provides the information to discriminate the spectral contributions. To minimize the influence of contaminating electrons, small (6x6cm2 ) fields were used. The measured depth dose is represented as a linear combination of basis functions, namely the depth doses of monoenergetic photon beams derived by Monte Carlo simulations. The weights of the basis functions were obtained with the Cimmino feasibility algorithm, which examines in each iteration the discrepancy between predicted and measured depth dose. For 6 and 15 MV photon beams of a clinical accelerator, the depth dose obtained from the derived spectral weights was within about 1% of the measured depth dose at all depths. Because the problem is ill conditioned, solutions for the spectrum can fluctuate with energy. Physically realistic smooth spectra for these photon beams appeared when a small margin (about ±1%) was attributed to the measured depth dose. The maximum energy of both derived spectra agreed with the measured energy of the electrons striking the target to within 1 MeV. The use of a feasibility method on minimally relaxed constraints provides realistic spectra quickly and interactively. (author)

  9. In-beam PET at high-energy photon beams: a feasibility study

    Science.gov (United States)

    Müller, H.; Enghardt, W.

    2006-04-01

    For radiation therapy with carbon ion beams, either for the stable isotope 12C or for the radioactive one 11C, it has been demonstrated that the β+-activity distribution created or deposited, respectively, within the irradiated volume can be visualized by means of positron emission tomography (PET). The PET images provide valuable information for quality assurance and precision improvement of ion therapy. Dedicated PET scanners have been integrated into treatment sites at the Heavy Ion Medical Accelerator at Chiba (HIMAC), Japan, and the Gesellschaft für Schwerionenforschung (GSI), Germany, to make PET imaging feasible during therapeutic irradiation (in-beam PET). A similar technique may be worthwhile for radiotherapy with high-energy bremsstrahlung. In addition to monitoring the dose delivery process which in-beam PET has been primarily developed for, it may be expected that radiation response of tissue can be detected by means of in-beam PET. We investigate the applicability of PET for treatment control in the case of using bremsstrahlung spectra produced by 15-50 MeV electrons. Target volume activation due to (γ, n) reactions at energies above 20 MeV yields moderate β+-activity levels, which can be employed for imaging. The radiation from positrons produced by pair production is not presently usable because the detectors are overloaded due to the low duty factor of medical electron linear accelerators. However, the degradation of images caused by positron motion between creation and annihilation seems to be tolerable.

  10. An Overview of Brazilian Developments in Beamed Energy Aerospace Propulsion and Vehicle Performance Control

    International Nuclear Information System (INIS)

    Minucci, M. A. S.

    2008-01-01

    Beamed energy propulsion and beamed energy vehicle performance control concepts are equally promising and challenging. In Brazil, the two concepts are being currently investigated at the Prof Henry T Nagamatsu Laboratory of Aerothermodynamics and Hypersonics, of the Institute for Advanced Studies--IEAv, in collaboration with the Rensselaer Polytechnic Institute--RPI, Troy, NY, and the United States Air force Research Laboratory-AFRL. Until recently, only laser energy addition for hypersonic flow control was being investigated at the Laboratory using a 0.3 m nozzle exit diameter hypersonic shock tunnel, T2, and two 7 joule CO 2 TEA lasers. Flow visualization, model pressure and heat flux measurements of the laser energy addition perturbed flow around a model were produced as a result of this joint IEAv-RPI investigation. Presently, with the participation of AFRL and the newly commissioned 0.6 m. nozzle exit diameter hypersonic shock tunnel, T3, a more ambitious project is underway. Two 400 Joule Lumonics 620 CO 2 TEA lasers will deliver a 20 cm X 25 cm propulsive laser beam to a complete laser propelled air breather/rocket hypersonic engine, located inside T3 test section. Schlieren photographs of the flow inside de engine as well as surface and heat flux measurements will be performed for free stream Mach numbers ranging from 6 to 25. The present paper discusses past, present and future Brazilian activities on beamed energy propulsion and related technologies

  11. Energy analysis of the ion beam from plasma focus

    International Nuclear Information System (INIS)

    Kilic, H.; Nardi, V.; Prior, W.

    1984-01-01

    The authors have experimentally determined the energy spectrum of a deuteron beam in the energy interval 100 KeV ≤ E ≤ 10 MeV, with typical beam current I ≥ 1-2 A. A 5 kJ (15 kV, 49 μF) plasma focus machine is used to generate the ion beam at relatively low pressure 3-4 Torr D/sub 2/ (beam anode) and at higher pressure 6-8 Torr D/sub 2/ (high-neutron-yield mode). The spectrum is obtained from two different methods, i.e. from ion time of flight - by using time delays of Faraday cup signals with respect to hard x-ray signals - and from ion filtering, (mylar filter with different thickness from 2.5 μm up to 500 μm are used to cover the Faraday cup). The Faraday cup is located in a differentially pumed chamber (10/sup -4/ - 10/sup -5/ Torr) which is separated from the plasma focus chamber (8-3 Torr) by a 150 μm diam. pinhole (12.5 μm thick tungsten foil). The pinhole and Faraday cup are positioned on the gun axis at a distance of 15 cm and 25 cm from the end of the anode respectively

  12. Evaluation of the spectral distribution of X-ray beams from measurements on the scattered radiation

    International Nuclear Information System (INIS)

    Casnati, E.; Baraldi, C.

    1980-01-01

    Most of the phenomena activated by photons with energies below 100 keV show an apparent or real dependence on the quantum energy. Therefore, knowledge of the beam energy characteristics is of primary importance for interpretation of the irradiation results. The greatest difficulty arises from the high flux density of the beams usually employed which does not allow direct measurements of the beam. A method was developed which permits evaluation of the spectral distribution of the X-ray beam from a spectrometric measurement of the radiation scattered by a thin foil of a suitable metal. This makes possible a new and more rational approach to the measurement of X-rays in the energy range where the interaction parameters show a large photon energy dependence. The corrections required by the presence of some collateral effects, among which the most important is the coexistence of the coherent and incoherent scattering, must be evaluated. The knowledge of the spectral distribution is of immediate usefulness for studies of radiation damage in biological and other materials, for the calibration of radiation measuring instruments and for the improvement of the radiological instrumentation response which contributes to reducing the patient's dose. (H.K.)

  13. Dose distribution considerations of medium energy electron beams at extended source-to-surface distance

    International Nuclear Information System (INIS)

    Saw, Cheng B.; Ayyangar, Komanduri M.; Pawlicki, Todd; Korb, Leroy J.

    1995-01-01

    Purpose: To determine the effects of extended source-to-surface distance (SSD) on dose distributions for a range of medium energy electron beams and cone sizes. Methods and Materials: The depth-dose curves and isodose distributions of 6 MeV, 10 MeV, and 14 MeV electron beams from a dual photon and multielectron energies linear accelerator were studied. To examine the influence of cone size, the smallest and the largest cone sizes available were used. Measurements were carried out in a water phantom with the water surface set at three different SSDs from 101 to 116 cm. Results: In the region between the phantom surface and the depth of maximum dose, the depth-dose decreases as the SSD increases for all electron beam energies. The effects of extended SSD in the region beyond the depth of maximum dose are unobservable and, hence, considered minimal. Extended SSD effects are apparent for higher electron beam energy with small cone size causing the depth of maximum dose and the rapid dose fall-off region to shift deeper into the phantom. However, the change in the depth-dose curve is small. On the other hand, the rapid dose fall-off region is essentially unaltered when the large cone is used. The penumbra enlarges and electron beam flatness deteriorates with increasing SSD

  14. Measuring and Comparing Energy Flexibilities

    DEFF Research Database (Denmark)

    Valsomatzis, Emmanouil; Hose, Katja; Pedersen, Torben Bach

    2015-01-01

    Flexibility in energy supply and demand becomes more and more important with increasing Renewable Energy Sources (RES) production and the emergence of the Smart Grid. So-called prosumers, i.e., entities that produce and/or consume energy, can offer their inherent flexibilities through so......-called demand response and thus help stabilize the energy markets. Thus, prosumer flexibility becomes valuable and the ongoing Danish project TotalFlex [1] explores the use of prosumer flexibility in the energy market using the concept of a flex-offer [2], which captures energy flexibilities in time and...... induced by time and amount individually, and by their com- bination. To this end, we introduce several flexibility measures that take into account the combined effect of time and energy on flex-offer flexibility and discuss their respective pros and cons through a number of realistic examples....

  15. Molecular beam studies of energy transfer in scattering from crystal surfaces

    International Nuclear Information System (INIS)

    Guthrie, W.L.

    1983-01-01

    The translational energy distributions and angular distributions of D 2 O produced from the reaction of incident D 2 and O 2 on a (111) platinum single crystal surface have been measured through the use of a molecular beam-surface scattering apparatus equipped with a time-of-flight spectrometer. The translation energies were measured over the surface temperature range T/sub s/ = 664 K - 913 K and at scattering angles of 7 0 and 40 0 from the surface normal. The D 2 O translational energy, , was found to be approximately half the equilibrium value over the temperature range examined, with /2k varying from 280 K to 480 K. These results are discussed in terms of a non-equilibrium desorption model. The two-photon ionization spectrometer was built to investigate the internal rotational and vibrational energy distributions of NO scattered from Pt(111) surfaces. The rotational energy distributions were measured over the crystal temperature range of T/sub s/ = 400 K - 1200 K. The translational energy distributions and angular distributions were measured using the time-of-flight spectrometer over the crystal temperature range of 400 K - 110 K and for beam translational energies of 0.046 eV, 0.11 eV and 0.24 eV, so that complete energy exchange information for translation, rotation and vibration is available for this gas-surface system. Significant energy transfer was observed in all three modes

  16. Direct measurement of electron beam quality conversion factors using water calorimetry.

    Science.gov (United States)

    Renaud, James; Sarfehnia, Arman; Marchant, Kristin; McEwen, Malcolm; Ross, Carl; Seuntjens, Jan

    2015-11-01

    In this work, the authors describe an electron sealed water calorimeter (ESWcal) designed to directly measure absorbed dose to water in clinical electron beams and its use to derive electron beam quality conversion factors for two ionization chamber types. A functioning calorimeter prototype was constructed in-house and used to obtain reproducible measurements in clinical accelerator-based 6, 9, 12, 16, and 20 MeV electron beams. Corrections for the radiation field perturbation due to the presence of the glass calorimeter vessel were calculated using Monte Carlo (MC) simulations. The conductive heat transfer due to dose gradients and nonwater materials was also accounted for using a commercial finite element method software package. The relative combined standard uncertainty on the ESWcal dose was estimated to be 0.50% for the 9-20 MeV beams and 1.00% for the 6 MeV beam, demonstrating that the development of a water calorimeter-based standard for electron beams over such a wide range of clinically relevant energies is feasible. The largest contributor to the uncertainty was the positioning (Type A, 0.10%-0.40%) and its influence on the perturbation correction (Type B, 0.10%-0.60%). As a preliminary validation, measurements performed with the ESWcal in a 6 MV photon beam were directly compared to results derived from the National Research Council of Canada (NRC) photon beam standard water calorimeter. These two independent devices were shown to agree well within the 0.43% combined relative uncertainty of the ESWcal for this beam type and quality. Absorbed dose electron beam quality conversion factors were measured using the ESWcal for the Exradin A12 and PTW Roos ionization chambers. The photon-electron conversion factor, kecal, for the A12 was also experimentally determined. Nonstatistically significant differences of up to 0.7% were found when compared to the calculation-based factors listed in the AAPM's TG-51 protocol. General agreement between the relative

  17. Shadow photography method for beam emittance measurement

    International Nuclear Information System (INIS)

    Kashkovskij, V.V.; Lisin, V.A.

    1988-01-01

    Improved technique of shadow photography which allows to measure rather simply and accurately the angular distribution of electrons extracted from betatron is described. Measurement accuracy of particle flight angles is determined by setting of rods relatively to the plane of photographic paper sheet, their diameter and shadow trace length. Incidental angle deviation of rod axes contributes mainly into the error. Mean root-square error constituted 2-3% according to the results of several measurements of angles

  18. Squids, snakes, and polarimeters: A new technique for measuring the magnetic moments of polarized beams

    International Nuclear Information System (INIS)

    Cameron, P.R.; Luccio, A.U.; Shea, T.J.; Tsoupas, N.; Goldberg, D.A.

    1997-01-01

    Effective polarimetry at high energies in hadron and lepton synchrotrons has been a long-standing and difficult problem. In synchrotrons with polarized beams it is possible to cause the direction of the polarization vector of a given bunch to alternate at a frequency which is some subharmonic of the rotation frequency. This can result in the presence of lines in the beam spectrum which are due only to the magnetic moment of the beam and which are well removed from the various lines due to the charge of the beam. The magnitude of these lines can be calculated from first principles. They are many orders of magnitude weaker than the Schottky signals. Measurement of the magnitude of one of these lines would be an absolute measurement of beam polarization. For measuring magnetic field, the Superconducting Quantum Interference Device, or squid, is about five orders of magnitude more sensitive than any other transducer. Using a squid, such a measurement might be accomplished with the proper combination of shielding, pickup loop design, and filtering. The resulting instrument would be fast, non-destructive, and comparatively cheap. In addition, techniques developed in the creation of such an instrument could be used to measure the Schottky spectrum in unprecedented detail. We present specifics of a polarimeter design for the Relativistic Heavy Ion Collider (RHIC) and briefly discuss the possibility of using this technique to measure polarization at high-energy electron machines like LEP and HERA. copyright 1997 American Institute of Physics

  19. Energy efficiency policies and measures

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document makes a review of the energy efficiency and demand side management (DSM) policies and measures in European Union countries and Norway in 1999: institutional changes, measures and programmes, budget, taxation, existence of a national DSM programme, national budgets for DSM programmes, electricity pricing: energy/environment tax, national efficiency standards and regulation for new electrical appliances, implementation of Commission directives, efficiency requirements, labelling, fiscal and economic incentives. (J.S.)

  20. Refined beam measurements on the SNS H- injector

    Science.gov (United States)

    Han, B. X.; Welton, R. F.; Murray, S. N.; Pennisi, T. R.; Santana, M.; Stinson, C. M.; Stockli, M. P.

    2017-08-01

    The H- injector for the SNS RFQ accelerator consists of an RF-driven, Cs-enhanced H- ion source and a compact, two-lens electrostatic LEBT. The LEBT output and the RFQ input beam current are measured by deflecting the beam on to an annular plate at the RFQ entrance. Our method and procedure have recently been refined to improve the measurement reliability and accuracy. The new measurements suggest that earlier measurements tended to underestimate the currents by 0-2 mA, but essentially confirm H- beam currents of 50-60 mA being injected into the RFQ. Emittance measurements conducted on a test stand featuring essentially the same H- injector setup show that the normalized rms emittance with 0.5% threshold (99% inclusion of the total beam) is in a range of 0.25-0.4 mm.mrad for a 50-60 mA beam. The RFQ output current is monitored with a BCM toroid. Measurements as well as simulations with the PARMTEQ code indicate an underperforming transmission of the RFQ since around 2012.

  1. Beam lifetime measurement and analysis in Indus-2 electron ...

    Indian Academy of Sciences (India)

    Indus operation and Accelerator Physics Design Division, Raja Ramanna Centre for Advanced. Technology, Indore 452 013, .... with residual gas atoms. The rate of particle loss can be written as [8],. −. dI dt ... Coulomb scattering of charged particles in a stored beam causes an exchange of energy between transverse and ...

  2. Therapy imaging: Limitations of imaging with high energy x-ray beams

    International Nuclear Information System (INIS)

    Munro, P.; Rawlinson, J.A.; Fenster, A.

    1987-01-01

    One of the major problems in radiation therapy is ensuring that the correct region of the patient receives the prescribed x-ray treatment and that the surrounding tissues are spared. One way to identify patient positioning errors is to make an image using the radiotherapy treatment beam. The authors have examine4d two of the factors that can influence the quality of images made with high energy x-ray beams: (i) the size of the x-ray source, and; (ii) the signal-to-noise characteristics of the detectors used to form images with high energy x-ray beams. They have developed a novel method of measuring the source distributions for /sup 60/Co machines and linear accelerators and from the measurements have been able to obtain the modulation transfer functions of their x-ray sources. They also measured the modulation transfer functions (MTFs) and the noise power spectra (NPS) of the x-ray detectors. Based on these measurements, the authors conclude that images made with high energy x-ray beams are limited by film granularity and that improved images can be obtained by alternative detector systems

  3. Polarized neutron beam properties for measuring parity-violating spin rotation in liquid {sup 4}He

    Energy Technology Data Exchange (ETDEWEB)

    Micherdzinska, A.M., E-mail: amicherd@gwu.ed [Indiana University/IU Center for Exploration of Energy and Matter, Bloomington, IN 47408 (United States); George Washington University, Washington, DC 20052 (United States); Bass, C.D. [Indiana University/IU Center for Exploration of Energy and Matter, Bloomington, IN 47408 (United States); National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Bass, T.D. [Indiana University/IU Center for Exploration of Energy and Matter, Bloomington, IN 47408 (United States); Gan, K. [George Washington University, Washington, DC 20052 (United States); Luo, D. [Indiana University/IU Center for Exploration of Energy and Matter, Bloomington, IN 47408 (United States); Markoff, D.M. [North Carolina Central University, Durham, NC 27707 (United States); Mumm, H.P.; Nico, J.S. [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Opper, A.K. [George Washington University, Washington, DC 20052 (United States); Sharapov, E.I. [Joint Institute for Nuclear Research, Dubna 141980 (Russian Federation); Snow, W.M. [Indiana University/IU Center for Exploration of Energy and Matter, Bloomington, IN 47408 (United States); Swanson, H.E. [University of Washington/CENPA, Seattle, WA 98195 (United States); Zhumabekova, V. [Al-Farabi Kazakh National University, Al-Farabi Ave. 71, 050038 Almaty (Kazakhstan)

    2011-03-01

    Measurements of parity-violating neutron spin rotation can provide insight into the poorly understood nucleon-nucleon weak interaction. Because the expected rotation angle per unit length is small (10{sup -7} rad/m), several properties of the polarized cold neutron beam phase space and the neutron optical elements of the polarimeter must be measured to quantify possible systematic effects. This paper presents (1) an analysis of a class of possible systematic uncertainties in neutron spin rotation measurements associated with the neutron polarimetry, and (2) measurements of the relevant neutron beam properties (intensity distribution, energy spectrum, and the product of the neutron beam polarization and the analyzing power as a function of the beam phase space properties) on the NG-6 cold neutron beam-line at the National Institute of Standards and Technology Center for Neutron Research. We conclude that the phase space nonuniformities of the polarimeter in this beam are small enough that a parity-violating neutron spin rotation measurement in n-{sup 4}He with systematic uncertainties at the 10{sup -7} rad/m level is possible.

  4. Beam dynamics and error study of the medium energy beam transport line in the Korea Heavy-Ion Medical Accelerator

    Science.gov (United States)

    Kim, Chanmi; Kim, Eun-San; Hahn, Garam

    2016-11-01

    The Korea Heavy Ion Medical Accelerator consists of an injector and a synchrotron for an ion medical accelerator that is the first carbon-ion therapy system in Korea. The medium energy beam transport(MEBT) line connects the interdigital H-mode drift tube linac and the synchrotron. We investigated the beam conditions after the charge stripper by using the LISE++ and the SRIM codes. The beam was stripped from C4+ into C6+ by using the charge stripper. We investigated the performance of a de-buncher in optimizing the energy spread and the beam distribution in z-dW/W (direction of beam progress-beam and energy) phase. We obtained the results of the tracking simulation and the error analysis by using the TRACK code. Possible misalignments and rotations of the magnets were considered in the simulations. States of the beam were examined when errors occurred in the magnets by the applying analytic fringe field model in TRACK code. The condition for the beam orbit was optimized by using correctors and profile monitors to correct the orbit. In this paper, we focus on the beam dynamics and the error studies dedicated to the MEBT beam line and show the optimized beam parameters for the MEBT.

  5. Enhanced creation of high energy particles in colliding laser beams

    OpenAIRE

    Kuchiev, Michael; Ingham, Julian

    2015-01-01

    The creation of particles by two colliding strong laser beams is considered. It is found that the electron-positron pairs created in the laser field via the Schwinger mechanism may recollide after one or several oscillations in the field. Their collision can take place at high energy, which the pair gains from the field. As a result, high energy gamma quanta can be created by inelastic scattering or annihilation of the pair. Moreover, heavy particles such as muon pairs may also be created via...

  6. A SIMPLE METHOD FOR MEASURING THE ELECTRON-BEAM MAGNETIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Halavanau, A. [Fermilab; Qiang, G. [Tsinghua U., Beijing, Dept. Eng. Phys.; Wisniewski, E. [Argonne; Ha, G. [POSTECH, Pohang; Power, J. [Argonne; Piot, P. [Fermilab

    2016-10-18

    There are a number of projects that require magnetized beams, such as electron cooling or aiding in “flat” beam transforms. Here we explore a simple technique to characterize the magnetization, observed through the angular momentum of magnetized beams. These beams are produced through photoemission. The generating drive laser first passes through microlens arrays (fly-eye light condensers) to form a transversely modulated pulse incident on the photocathode surface [1]. The resulting charge distribution is then accelerated from the photocathode. We explore the evolution of the pattern via the relative shearing of the beamlets, providing information about the angular momentum. This method is illustrated through numerical simulations and preliminary measurements carried out at the Argonne Wakefield Accelerator (AWA) facility are presented.

  7. MD 979: Beta-beating measurements on colliding beams

    CERN Document Server

    Goncalves Jorge, Patrik; Pieloni, Tatiana; Buffat, Xavier; Carlier, Felix Simon; Coello De Portugal - Martinez Vazquez, Jaime Maria; Fol, Elena; Langner, Andy Sven; Medina Medrano, Luis Eduardo; Olexa, Jakub; Tomas Garcia, Rogelio; Valuch, Daniel; Wegscheider, Andreas; CERN. Geneva. ATS Department

    2017-01-01

    The HL-LHC high brightness beams will give a large β-beating due to the head-on and long-range interactions since a beam-beam parameter of 0.01 per Interaction Point (IP) is expected. The β-heating induced by two head-on collision reaches 15%. A third IP, i.e. IP8, could bring the β-heating up to 24%. The aim of the Machine Development (MD) study was to test optics measurements with AC dipole and ADT on colliding beams at injection and to implement a correction of the β-heating due to to head-on collision in the two experiments IP1&5. Int his note, we summarize the first results of this test performed in the LHC.

  8. Application of methodology for calibration of instruments utilized in dosimetry of high energy beams, for radiodiagnosis

    International Nuclear Information System (INIS)

    Potiens, Maria P.A.; Caldas, Linda V.E.

    2000-01-01

    The radiation qualities recommended by the IEC 1267 standard for the calibration of instruments used in diagnostic radiology measurements were established using a neo-diagnomax X-ray system (125 kV). The RQR radiation qualities are recommended to test ionization chambers used in non attenuated beams, and the RQA radiation qualities in attenuated beams (behind a phantom). To apply the methodology, 6 ionization chambers commonly used in diagnostic radiology were tested. The higher energy dependence (17%) was obtained for an ionization chamber recommended for mammography beams, that is not the case of the X radiation system used in this work. The other ionization chambers presented good performance in terms of energy (maximum of 5%), therefore within the limits of the international recommendations for this kind of instrument. (author)

  9. E-beam pumping and energy extraction from large-aperture KrF amplifiers

    Science.gov (United States)

    Zvorykin, V. D.; Arlantsev, S. V.; Bakaev, V. G.; Levchenko, A. O.; Molchanov, A. G.; Ustinovskii, N. N.

    2006-01-01

    Experiments were performed at 100-J-class GARPUN KrF laser installation on optimization of e-beam pumping and amplification of 20-ns pulses in e-beam-pumped amplifiers with gain volumes of 10 × 10 × 100 cm 3 and 16 × 18 × 100 cm 3. Amplified spontaneous emission (ASE) was measured in the near field close to the output window and in the far field along the amplifier axis. Suppression of transverse ASE by amplification of a laser signal was also investigated. The experimental data were compared with numerical simulations of e-beam transport using Monte Carlo code and 3-D numerical simulations of large-aperture single-pass and double-pass KrF laser amplifiers. Finally, the verified numerical codes were applied for optimization studies of large-scale KrF amplifiers with output energy up to 10 kJ being developed for Inertial Fusion Energy application.

  10. Cherenkov Detector for Beam Quality Measurement

    CERN Document Server

    AUTHOR|(CDS)2078842

    2016-01-01

    A new detector to measure the machine induced background at larger radiihas been developed and installed in the CMS experiment at LHC. Itconsists of 40 modules, each comprising a quartz bar read out by aphotomultiplier. Since Cerenkov radiation is emitted in a forward conearound the charged particle trajectory, these detectors can distinguishthe directions of the machine induced background.The back-end consists of a microTCA readout with excellent time resolution.The performance of the detector modules measured in several test-beamcampaigns will be reported. The installation in CMS will be described, andfirst results about operating the detector during data taking will begiven.

  11. Highly Compressed Ion Beams for High Energy Density Science

    CERN Document Server

    Friedman, Alex; Briggs, Richard J; Callahan, Debra; Caporaso, George; Celata, C M; Davidson, Ronald C; Faltens, Andy; Grant-Logan, B; Grisham, Larry; Grote, D P; Henestroza, Enrique; Kaganovich, Igor D; Lee, Edward; Lee, Richard; Leitner, Matthaeus; Nelson, Scott D; Olson, Craig; Penn, Gregory; Reginato, Lou; Renk, Tim; Rose, David; Sessler, Andrew M; Staples, John W; Tabak, Max; Thoma, Carsten H; Waldron, William; Welch, Dale; Wurtele, Jonathan; Yu, Simon

    2005-01-01

    The Heavy Ion Fusion Virtual National Laboratory (HIF-VNL) is developing the intense ion beams needed to drive matter to the High Energy Density (HED) regimes required for Inertial Fusion Energy (IFE) and other applications. An interim goal is a facility for Warm Dense Matter (WDM) studies, wherein a target is heated volumetrically without being shocked, so that well-defined states of matter at 1 to 10 eV are generated within a diagnosable region. In the approach we are pursuing, low to medium mass ions with energies just above the Bragg peak are directed onto thin target "foils," which may in fact be foams or "steel wool" with mean densities 1% to 100% of solid. This approach complements that being pursued at GSI, wherein high-energy ion beams deposit a small fraction of their energy in a cylindrical target. We present the requirements for warm dense matter experiments, and describe suitable accelerator concepts, including novel broadband traveling wave pulse-line, drift-tube linac, RF, and single-gap approa...

  12. A cooler for intense low-energy ion beams

    International Nuclear Information System (INIS)

    Varentsov, V.L.; Habs, D.

    2002-01-01

    A new efficient cooling technique for intense low-energy ion beams is explored. The primary ions are directly injected through a converging-diverging nozzle into a cold expanding supersonic He carrier gas jet. There they adopt the temperature and overall velocity of the gas jet, creating an e - He + plasma in the slowing down process. In the RF-funnel that is placed on axis in the immediate vicinity of the nozzle exit plane the He + ions and electrons penetrate into the funnel walls and the He + ions have neutralized, while the desired more heavy ions are confined and focused inside the funnel. After reducing the plasma to a small level in the funnel the ion beam is further purified and compressed passing through a RFQ channel. Finally, the cooled low-emittance ion beam is extracted into high vacuum conditions through the skimmer placed behind the RFQ channel. The operation of the new ion beam cooling technique has been studied by means of numerical simulations. The results of calculations are presented

  13. A cooler for intense low-energy ion beams

    CERN Document Server

    Varentsov, V L

    2002-01-01

    A new efficient cooling technique for intense low-energy ion beams is explored. The primary ions are directly injected through a converging-diverging nozzle into a cold expanding supersonic He carrier gas jet. There they adopt the temperature and overall velocity of the gas jet, creating an e sup - He sup + plasma in the slowing down process. In the RF-funnel that is placed on axis in the immediate vicinity of the nozzle exit plane the He sup + ions and electrons penetrate into the funnel walls and the He sup + ions have neutralized, while the desired more heavy ions are confined and focused inside the funnel. After reducing the plasma to a small level in the funnel the ion beam is further purified and compressed passing through a RFQ channel. Finally, the cooled low-emittance ion beam is extracted into high vacuum conditions through the skimmer placed behind the RFQ channel. The operation of the new ion beam cooling technique has been studied by means of numerical simulations. The results of calculations are...

  14. Absolute luminosity measurement at LHCb with beam-gas imaging

    CERN Document Server

    Barschel, C

    2013-01-01

    A novel technique to measure the absolute luminosity at the Large Hadron Collider (LHC) using beam-gas interactions has been successfully used in the LHCb experiment. A gas injection device (SMOG) has been installed in the LHCb experiment to increase the pressure around the interaction point during dedicated fills. The Beam-Gas Imaging method (BGI) has now the potential to surpass the accuracy of the commonly used *van der Meer scan* method (VDM). The technique has been used in 10 LHC fills during 2012 including and also provided a first luminosity measurement for proton-lead collisions. This talk presents the principles of the gas injection and the improvements reached with the increased pressure. Furthermore the gas injection increased the accuracy measurement of the so-called ghost charges and also intensities per bunch. Those uncertainties are becoming the dominating factor because the uncertainty on the total beam current have been reduced.

  15. Fast Beam Intensity Measurements for the LHC

    CERN Document Server

    Belohrad, D

    Particle accelerators are constructed and operated for a wide variety of applications. In particle physics - the branch of physics that studies the elementary constituents of matter and forces between them - high energy accelerators are used to look deep into the structure of matter. Medical particle accelerators are used for example in medicine to treat tumours [31], in imaging techniques such as Positron Emission Tomography (PET) [24], or for the radio-isotopes production. They also serve in many other industrial branches, e.g. geology, radiocarbon dating [39], molecular complex spectroscopy, lithography, food preservation etc. The eld of accelerator technology draws knowledge and expertise from a wide range of scientic disciplines and uses the latest technical knowledge. The incomplete list of covered disciplines includes mathematics, physics, electronics, computing, electromagnetic eld technology, microwave technology, cryogenics, vacuum technology, special materials, mechanical engineering or civil engin...

  16. In situ beam angle measurement in a multi-wafer high current ion implanter

    International Nuclear Information System (INIS)

    Freer, B.S.; Reece, R.N.; Graf, M.A.; Parrill, T.; Polner, D.

    2005-01-01

    Direct, in situ measurement of the average angle and angular content of an ion beam in a multi-wafer ion implanter is reported for the first time. A new type of structure and method are described. The structures are located on the spinning disk, allowing precise angular alignment to the wafers. Current that passes through the structures is known to be within a range of angles and is detected behind the disk. By varying the angle of the disk around two axes, beam current versus angle is mapped and the average angle and angular spread are calculated. The average angle measured in this way is found to be consistent with that obtained by other techniques, including beam centroid offset and wafer channeling methods. Average angle of low energy beams, for which it is difficult to use other direct methods, is explored. A 'pencil beam' system is shown to give average angle repeatability of 0.13 deg. (1σ) or less, for two low energy beams under normal tuning variations, even though no effort was made to control the angle

  17. Heavy ion beam probe development for the plasma potential measurement on the TUMAN-3M tokamak

    International Nuclear Information System (INIS)

    Askinazi, L.G.; Kornev, V.A.; Lebedev, S.V.; Tukachinsky, A.S.; Zhubr, N.A.; Dreval, N.B.; Krupnik, L.I.

    2004-01-01

    The peculiarities of the heavy ion beam probe implementation on the small aspect ratio tokamak TUMAN-3M are analyzed. The toroidal displacement of beam trajectory due to the high I pl /B tor ratio is taken into account when designing the layout of the diagnostic. Numerical calculation of beam trajectories using realistic configuration of TUMAN-3M magnetic fields and parabolic plasma current profile resulted in proper adjustment of probing and detection parameters (probing ion material, energy, entrance angles, detector location, and orientation). Secondary ion energy analyzer gain functions G and F were measured in situ using neutral hydrogen puffed in the tokamak vessel as a target for secondary ions production. The detector unit featured split-plate design and had additional electrodes for secondary electron emission suppression. As a result, the diagnostic is now capable of plasma potential evolution measurement and is sensitive enough to trace the potential profile evolution at the L-H mode transition

  18. Flatness of two-dimensional beam profile measured with an ionization chamber array

    International Nuclear Information System (INIS)

    Stefanovski, Z.

    2006-01-01

    Open beam profiles are basic dosimetric characteristics for the formation of the dose calculation algorithms parameters and for determination of beam quality. One characteristic of the beam profiles as a measure for the beam quality is the field flatness defined as ratio of the difference of maximum and minimum dose in central 80% of the field to the sum of these doses in the part of the field. The measurements, instead with an ordinary ionization chamber, were performed with a chamber array in two depths (1.6 cm and 10 cm) in water phantom. Nominal photon beam energy was 6 MV and field size was 25 cm x 25 cm on the water surface. Field flatness was in the range of 1-2 % which is in accordance with the data acquired during the acceptance testing and commissioning of the accelerators. with the array chamber the beam profiles can be performed quickly and preciously. These features recommend a chamber array as an excellent tool for periodic quality control of beam profiles. (Author)

  19. Flexible core masking technique for beam halo measurements with high dynamic range

    International Nuclear Information System (INIS)

    Egberts, J; Welsch, C P

    2010-01-01

    A thorough understanding of halo formation and its possible control is highly desirable for essentially all particle accelerators. Particles outside the beam core are not only lost for further experiments, they are also likely to hit the beam pipe, and activate this, as well as accelerator and experimental components in close proximity, which makes work on the accelerator costly and time consuming. Well established techniques for transverse beam profile measurements of electron or high energy hadron beams are the observation of synchrotron radiation, optical transition radiation or the like. A particular challenge, however, is the detection of particles in the tail regions of the beam distribution in close proximity of the very intense beam core. Results from laboratory measurements on two different devices are presented that might form the technical base of a future beam halo monitor: the novel SpectraCam XDR camera system which has an intrinsically high dynamic range due to its unique pixel design, and a flexible masking technique based on a DMD micro mirror array which allows for a fast mask generation to blank out the central core.

  20. Resolution and drift measurements on the Advanced Photon Source beam position monitors

    International Nuclear Information System (INIS)

    Chung, Y.; Kahana, E.

    1994-01-01

    The resolution and long-term drift of the Advanced Photon Source (APS) beam position monitor (BPM) electronics were measured using the charged particle beams in the ESRF storage ring with various beam current and configurations (single bunch, 8 and 16 equally spaced bunches, and 1/3-fill). The energy of the stored electrons was 6 GeV. The integrated BPM electronics system as used for this work is capable of measuring the beam position on a turn-by-turn basis, which can be accumulated for N turns (N = 2 n , n = 1, 2, ... , 11). Estimation of the BPM resolution apart from the low-frequency beam motion was made by measuring the standard deviation in the measured beam position with different Ns. The analysis of the results indicates a BPM resolution of 18/√ N [μm] for the APS storage ring, which is equivalent to 0.07 μm/√Hz. For the miniature insertion device BPM with 2.8 times higher sensitivity, the resolution will be 0.02 μm/√Hz. The long-term drift of the BPM electronics independent of the actual beam motion was measured at 2 μm/hr, which settled after approximately 1.5 hours. This drift can be attributed mainly to the temperature effect. Comparison of the results with the laboratory measurements shows good agreement. Implication of the BPM resolution limit on the proposed global and local beam position feedback systems for the APS storage ring will also be discussed

  1. Low energy intense electron beams with extra-low energy spread

    International Nuclear Information System (INIS)

    Aleksandrov, A.V.; Calabrese, R.; Ciullo, G.; Dikansky, N.S.; Guidi, V.; Kot, N.C.; Kudelainen, V.I.; Lamanna, G.; Lebedev, V.A.; Logachov, P.V.; Tecchio, L.; Yang, B.

    1994-01-01

    Maximum achievable intensity for low energy electron beams is a feature that is not very often compatible with low energy spread. We show that a proper choice of the source and the acceleration optics allows one to match them together. In this scheme, a GaAs photocathode excited by a single-mode infrared laser and adiabatic acceleration in fully magnetised optics enables the production of a low-energy-spread electron beam with relatively high intensity. The technological problems associated with the method are discussed together with its limitations. (orig.)

  2. Proportional counter measurements in neutron therapy beams

    International Nuclear Information System (INIS)

    Menzel, H.G.

    1984-01-01

    Dosimetry for clinical neutron therapy requires a characterization of radiation quality in addition to the specification of absorbed dose. Generally, a very simple approach has been adopted which consists in separating total absorbed dose into neutron and photon fractions. This is explained by the requirement of clinical dosimetry to apply methods suitable for routine measurements, by the lack of generally accepted improved alternatives, and by the fact that radiation quality is only one of several problems in neutron therapy not sufficiently solved. Spectra measured with low-pressure tissue-equivalent proportional counters (experimental microdosimetry) provide a detailed description of the physical properties of the radiation field at neutron therapy facilities. These descriptions are suitable for explaining the influence of different parameters (collimation, field size, phantom) on radiation quality. Although the physical properties of the radiation field as described by the measured microdosimetric distributions and quantities are not the only properties relevant for radiation effects, in general there are reasons to believe that they provide a suitable radiation quality characterization for the limited range of applications in neutron therapy. (author)

  3. Visualization and analysis of pulsed ion beam energy density profile with infrared imaging

    Science.gov (United States)

    Isakova, Y. I.; Pushkarev, A. I.

    2018-03-01

    Infrared imaging technique was used as a surface temperature-mapping tool to characterize the energy density distribution of intense pulsed ion beams on a thin metal target. The technique enables the measuring of the total ion beam energy and the energy density distribution along the cross section and allows one to optimize the operation of an ion diode and control target irradiation mode. The diagnostics was tested on the TEMP-4M accelerator at TPU, Tomsk, Russia and on the TEMP-6 accelerator at DUT, Dalian, China. The diagnostics was applied in studies of the dynamics of the target cooling in vacuum after irradiation and in the experiments with target ablation. Errors caused by the target ablation and target cooling during measurements have been analyzed. For Fluke Ti10 and Fluke Ti400 infrared cameras, the technique can achieve surface energy density sensitivity of 0.05 J/cm2 and spatial resolution of 1-2 mm. The thermal imaging diagnostics does not require expensive consumed materials. The measurement time does not exceed 0.1 s; therefore, this diagnostics can be used for the prompt evaluation of the energy density distribution of a pulsed ion beam and during automation of the irradiation process.

  4. Measurement of the mean radial position of a lead ion beam in the CERN PS

    CERN Document Server

    Belleman, J; González, J; Johnston, S; Schulte, E C; Thivent, E

    1996-01-01

    The intensity of the lead ion beam in the PS, nominally 4×108 charges of Pb53+ per bunch, is too low for the closed orbit measurement system. However, for successful acceleration it is sufficient to know the mean radial position (MRP). A system was thus designed for simultaneous acquisition of revolution frequency and magnetic field. The frequency measurement uses a direct digital synthesiser (DDS), phase-locked to the beam signal from a special high-sensitivity pick-up. The magnetic field is obtained from the so-called B-train. From these two values, the MRP is calculated. The precision depends on the frequency measurement and on the accuracy of the value for the magnetic field. Furthermore, exact knowledge of the transition energy is essential. This paper describes the hardware and software developed for the MRP system, and discusses the issue of calibration, with a proton beam, of the B measurement.

  5. Dosimetry of small circular beams of high energy photons for stereotactic radiosurgery and radiotherapy: the use of small ionization chambers

    International Nuclear Information System (INIS)

    Mazal, A.; Gaboriauid, G.; Zefkili, S.; Rosenwald, J.C.; Boutaudon, S.; Pontvert, D.

    1999-01-01

    The irradiation of small targets in the brain in a singe fraction (radiosurgery) or with a fractionated approach (stereotactic radiosurgery) with small beams of photons requires specific conditions to measure and to model the dosimetric data needed for treatment planning. In this work we present the method and materials adopted in our institution since 1988 to perform the dosimetry of high energy (6-23) circular photon beams with diameters ranging from 10 to 40 mm at the isocenter of linear accelerators, and its evolution as new dosimetric material became commercially available. in circular ionization chambers of small dimensions. We want to answer the following questions: Which are the minimal basic data needed to model small circular beams of high energy photons? Can we extrapolate or convert data from conventional data of larger beams? Which are the detectors well adapted for these kind of measurements and for which range of beam sizes?

  6. Ultralow energy ion beam surface modification of low density polyethylene.

    Science.gov (United States)

    Shenton, Martyn J; Bradley, James W; van den Berg, Jaap A; Armour, David G; Stevens, Gary C

    2005-12-01

    Ultralow energy Ar+ and O+ ion beam irradiation of low density polyethylene has been carried out under controlled dose and monoenergetic conditions. XPS of Ar+-treated surfaces exposed to ambient atmosphere show that the bombardment of 50 eV Ar+ ions at a total dose of 10(16) cm(-2) gives rise to very reactive surfaces with oxygen incorporation at about 50% of the species present in the upper surface layer. Using pure O+ beam irradiation, comparatively low O incorporation is achieved without exposure to atmosphere (approximately 13% O in the upper surface). However, if the surface is activated by Ar+ pretreatment, then large oxygen contents can be achieved under subsequent O+ irradiation (up to 48% O). The results show that for very low energy (20 eV) oxygen ions there is a dose threshold of about 5 x 10(15) cm(-2) before surface oxygen incorporation is observed. It appears that, for both Ar+ and O+ ions in this regime, the degree of surface modification is only very weakly dependent on the ion energy. The results suggest that in the nonequilibrium plasma treatment of polymers, where the ion flux is typically 10(18) m(-2) s(-1), low energy ions (<50 eV) may be responsible for surface chemical modification.

  7. Nanocomposite oxide thin films grown by pulsed energy beam deposition

    International Nuclear Information System (INIS)

    Nistor, M.; Petitmangin, A.; Hebert, C.; Seiler, W.

    2011-01-01

    Highly non-stoichiometric indium tin oxide (ITO) thin films were grown by pulsed energy beam deposition (pulsed laser deposition-PLD and pulsed electron beam deposition-PED) under low oxygen pressure. The analysis of the structure and electrical transport properties showed that ITO films with a large oxygen deficiency (more than 20%) are nanocomposite films with metallic (In, Sn) clusters embedded in a stoichiometric and crystalline oxide matrix. The presence of the metallic clusters induces specific transport properties, i.e. a metallic conductivity via percolation with a superconducting transition at low temperature (about 6 K) and the melting and freezing of the In-Sn clusters in the room temperature to 450 K range evidenced by large changes in resistivity and a hysteresis cycle. By controlling the oxygen deficiency and temperature during the growth, the transport and optical properties of the nanocomposite oxide films could be tuned from metallic-like to insulating and from transparent to absorbing films.

  8. Producing titanium-niobium alloy by high energy beam

    Energy Technology Data Exchange (ETDEWEB)

    Sharkeev, Yu. P., E-mail: sharkeev@ispms.tsc.ru [Institute of Strength Physics and Materials Science, SB RAS, 2/4 Akademicheski Prosp., Tomsk, 634055 (Russian Federation); National Research Tomsk Polytechnic University, 30 Lenin Av., Tomsk, 634050 (Russian Federation); Golkovski, M. G., E-mail: golkoski@mail.ru [Budker Institute of Nuclear Physics, 11 Akademika Lavrentiev Prosp., Novosibirsk, 630090 (Russian Federation); Glukhov, I. A., E-mail: gia@ispms.tsc.ru; Eroshenko, A. Yu., E-mail: eroshenko@ispms.tsc.ru; Fortuna, S. V., E-mail: s-fortuna@mail.ru [Institute of Strength Physics and Materials Science, SB RAS, 2/4 Akademicheski Prosp., Tomsk, 634055 (Russian Federation); Bataev, V. A., E-mail: bataev@vadm.ustu.ru [Novosibirsk State Technical University, 20 K. Marx Prosp., Novosibirsk, 630073 (Russian Federation)

    2016-01-15

    The research is involved in producing a Ti-Nb alloy surface layer on titanium substrate by high energy beam method, as well as in examining their structures and mechanical properties. Applying electron-beam cladding it was possible to produce a Ti-Nb alloy surface layer of several millimeters, where the niobium concentration was up to 40% at. and the structure itself could be related to martensite quenching structure. At the same time, a significant microhardness increase of 3200-3400 MPa was observed, which, in its turn, is connected with the formation of martensite structure. Cladding material of Ti-Nb composition could be the source in producing alloys of homogeneous microhardness and desired concentration of alloying niobium element.

  9. Crystals channel high-energy beams in the LHC

    CERN Multimedia

    CERN Bulletin

    2015-01-01

    Bent crystals can be used to deflect particle beams, as suggested by E. Tsyganov in 1976. Experimental demonstrations have been carried out for four decades in various laboratories worldwide. In recent tests, a bent crystal inserted into the LHC beam halo successfully channelled and deflected 6.5 TeV protons into an absorber, with reduced secondary irradiation.    Quasimosaic crystal for the LHC (developed by PNPI). Bent crystal technology was introduced at CERN and further developed for the LHC by the UA9 Collaboration. For about ten years, experts from CERN, INFN (Italy), Imperial College (UK), LAL (France), and PNPI, IHEP and JINR (Russia) have been investigating the advantages of using bent crystals in the collimation systems of high-energy hadron colliders. A bent crystal replacing the primary collimator can deflect the incoming halo deeply inside the secondary collimators, improving their absorption efficiency. “The bent crystals we have just tested at the world-record en...

  10. Fitting relationship between the beam quality β factor of high-energy laser and the wavefront aberration of laser beam

    Science.gov (United States)

    Ji, Zhong-Ye; Zhang, Xiao-Fang

    2018-01-01

    The mathematical relation between the beam quality β factor of high-energy laser and the wavefront aberration of laser beam is important in beam quality control theory of the high-energy laser weapon system. In order to obtain this mathematical relation, numerical simulation is used in the research. Firstly, the Zernike representations of typically distorted atmospheric wavefront aberrations caused by the Kolmogoroff turbulence are generated. And then, the corresponding beam quality β factors of the different distorted wavefronts are calculated numerically through fast Fourier transform. Thus, the statistical distribution rule between the beam quality β factors of high-energy laser and the wavefront aberrations of the beam can be established by the calculated results. Finally, curve fitting method is chosen to establish the mathematical fitting relationship of these two parameters. And the result of the curve fitting shows that there is a quadratic curve relation between the beam quality β factor of high-energy laser and the wavefront aberration of laser beam. And in this paper, 3 fitting curves, in which the wavefront aberrations are consisted of Zernike Polynomials of 20, 36, 60 orders individually, are established to express the relationship between the beam quality β factor and atmospheric wavefront aberrations with different spatial frequency.

  11. Recent beam probe measurements on EBT, TMX, and RENTOR

    Energy Technology Data Exchange (ETDEWEB)

    Hickok, R L

    1980-06-01

    It is noted that beam probe systems can provide accurate, reliable measurments of plasma space potential and nf(T/sub e/). Over some temperature range, at least, it should be possible to separate n and T/sub e/ by measuring the multiple ionization reaction products. It is also an ideal diagnostic for studying fluctuations since it provides a simultaneous measurement of phi and nf(T/sub e/) from the same point in the plasma and the measurements are continuous in time. Measurements can be made quasi-continuously in space by rapidly sweeping the beam. By using more than one detector it should be possible to make measurements simultaneously at two different observation points in the plasma.

  12. Recent beam probe measurements on EBT, TMX, and RENTOR

    International Nuclear Information System (INIS)

    Hickok, R.L.

    1980-06-01

    It is noted that beam probe systems can provide accurate, reliable measurments of plasma space potential and nf(T/sub e/). Over some temperature range, at least, it should be possible to separate n and T/sub e/ by measuring the multiple ionization reaction products. It is also an ideal diagnostic for studying fluctuations since it provides a simultaneous measurement of phi and nf(T/sub e/) from the same point in the plasma and the measurements are continuous in time. Measurements can be made quasi-continuously in space by rapidly sweeping the beam. By using more than one detector it should be possible to make measurements simultaneously at two different observation points in the plasma

  13. Plasma-parameter measurements using neutral-particle-beam attenuation

    International Nuclear Information System (INIS)

    Foote, J.H.; Molvik, A.W.; Turner, W.C.

    1982-01-01

    Intense and energetic neutral-particle-beam injection used for fueling or heating magnetically confined, controlled-fusion experimental plasmas can also provide diagnostic measurements of the plasmas. The attenuation of an atomic beam (mainly from charge-exchange and ionization interactions) when passing through a plasma gives the plasma line density. Orthogonal arrays of highly collimated detectors of the secondary-electron-emission type have been used in magnetic-mirror experiments to measure neutral-beam attenuation along chords through the plasma volume at different radial and axial positions. The radial array is used to infer the radial plasma-density profile; the axial array, to infer the axial plasma-density profile and the ion angular distribution at the plasma midplane

  14. Head-On Beam-Beam Interactions in High-Energy Hadron Colliders. GPU-Powered Modelling of Nonlinear Effects

    CERN Document Server

    AUTHOR|(CDS)2160109; Støvneng, Jon Andreas

    2017-08-15

    The performance of high-energy circular hadron colliders, as the Large Hadron Collider, is limited by beam-beam interactions. The strength of the beam-beam interactions will be higher after the upgrade to the High-Luminosity Large Hadron Collider, and also in the next generation of machines, as the Future Circular Hadron Collider. The strongly nonlinear force between the two opposing beams causes diverging Hamiltonians and drives resonances, which can lead to a reduction of the lifetime of the beams. The nonlinearity makes the effect of the force difficult to study analytically, even at first order. Numerical models are therefore needed to evaluate the overall effect of different configurations of the machines. For this thesis, a new code named CABIN (Cuda-Accelerated Beam-beam Interaction) has been developed to study the limitations caused by the impact of strong beam-beam interactions. In particular, the evolution of the beam emittance and beam intensity has been monitored to study the impact quantitatively...

  15. Neutrino velocity measurement with the OPERA experiment in the CNGS beam

    International Nuclear Information System (INIS)

    Brunetti, G.

    2011-05-01

    The thesis concerns the measurement of the neutrino velocity with the OPERA experiment in the CNGS beam. There are different theoretical models that allow for Lorentz violating effects which can be investigated with measurements on terrestrial neutrino beams. The MINOS experiment published in 2007 a measure on the muon neutrinos over a distance of 730 km finding a deviation with respect to the expected time of flight of 126 ns with a statistical error of 32 ns and a systematic error of 64 ns. The OPERA experiment observes as well muon neutrinos 730 km away from the source, with a sensitivity significantly better than MINOS thanks to the higher number of interactions in the detector due to the higher energy beam and the much more sophisticated timing system explicitly upgraded in view of the neutrino velocity measurement. This system is composed by atomic cesium clocks and GPS receivers operating in 'common view mode'. Thanks to this system a time-transfer between the two sites with a precision at the level of 1 ns is possible. Moreover, a Fast Waveform Digitizer was installed along the proton beam line at CERN in order to measure the internal time structure of the proton pulses that are sent to the CNGS target. The result on the neutrino velocity is the most precise measurement so far with terrestrial neutrino beams: the neutrino time of flight was determined with a statistical uncertainty of about 10 ns and a systematic uncertainty smaller than 20 nano-seconds. (author)

  16. Development of a high current 60 keV neutral lithium beam injector for beam emission spectroscopy measurements on fusion experiments

    Science.gov (United States)

    Anda, G.; Dunai, D.; Lampert, M.; Krizsanóczi, T.; Németh, J.; Bató, S.; Nam, Y. U.; Hu, G. H.; Zoletnik, S.

    2018-01-01

    A 60 keV neutral lithium beam system was designed and built up for beam emission spectroscopy measurement of edge plasma on the KSTAR and EAST tokamaks. The electron density profile and its fluctuation can be measured using the accelerated lithium beam-based emission spectroscopy system. A thermionic ion source was developed with a SiC heater to emit around 4-5 mA ion current from a 14 mm diameter surface. The ion optic is following the 2 step design used on other devices with small modifications to reach about 2-3 cm beam diameter in the plasma at about 4 m from the ion source. A newly developed recirculating sodium vapour neutralizer neutralizes the accelerated ion beam at around 260-280 °C even during long (manipulation techniques are applied to allow optimization, aiming, cleaning, and beam modulation. The maximum 60 keV beam energy with 4 mA ion current was successfully reached at KSTAR and at EAST. Combined with an efficient observation system, the Li-beam diagnostic enables the measurement of the density profile and fluctuations on the plasma turbulence time scale.

  17. Determination of the quenching correction factors for plastic scintillation detectors in therapeutic high-energy proton beams

    Science.gov (United States)

    Wang, L. L. W.; Perles, L. A.; Archambault, L.; Sahoo, N.; Mirkovic, D.; Beddar, S.

    2012-12-01

    Plastic scintillation detectors (PSDs) have many advantages over other detectors in small field dosimetry due to their high spatial resolution, excellent water equivalence and instantaneous readout. However, in proton beams, the PSDs undergo a quenching effect which makes the signal level reduced significantly when the detector is close to the Bragg peak where the linear energy transfer (LET) for protons is very high. This study measures the quenching correction factor (QCF) for a PSD in clinical passive-scattering proton beams and investigates the feasibility of using PSDs in depth-dose measurements in proton beams. A polystyrene-based PSD (BCF-12, ϕ0.5 mm × 4 mm) was used to measure the depth-dose curves in a water phantom for monoenergetic unmodulated proton beams of nominal energies 100, 180 and 250 MeV. A Markus plane-parallel ion chamber was also used to get the dose distributions for the same proton beams. From these results, the QCF as a function of depth was derived for these proton beams. Next, the LET depth distributions for these proton beams were calculated by using the MCNPX Monte Carlo code, based on the experimentally validated nozzle models for these passive-scattering proton beams. Then the relationship between the QCF and the proton LET could be derived as an empirical formula. Finally, the obtained empirical formula was applied to the PSD measurements to get the corrected depth-dose curves and they were compared to the ion chamber measurements. A linear relationship between the QCF and LET, i.e. Birks' formula, was obtained for the proton beams studied. The result is in agreement with the literature. The PSD measurements after the quenching corrections agree with ion chamber measurements within 5%. PSDs are good dosimeters for proton beam measurement if the quenching effect is corrected appropriately.

  18. Remote Electric Power Transfer Between Spacecrafts by Infrared Beamed Energy

    Science.gov (United States)

    Chertok, Boris E.; Evdokimov, Roman A.; Legostaev, Victor P.; Lopota, Vitaliy A.; Sokolov, Boris A.; Tugaenko, Vjacheslav Yu.

    2011-11-01

    High efficient wireless electric energy transmission (WET) technology between spacecrafts by laser channel is proposed. WET systems could be used for remote power supplying of different consumers in space. First of all, there are autonomous technology modules for microgravity experiments, micro and nano satellites, different equipment for explorations of planetary surfaces, space transport vehicles with electric rocket propulsion systems. The main components of the WET technology consist of radiation sources on the base of semiconductor IR laser diodes; systems for narrow laser beam creation; special photovoltaic receivers for conversion of monochromatic IR radiation with high energy density to electric power. The multistage space experiment for WET technology testing is described. During this experiment energy will be transmitted from International Space Station to another spacecrafts like cargo transport vehicles (Progress or/and ATV) and micro satellites.

  19. Risk and Machine Protection for Stored Magnetic and Beam Energies

    CERN Document Server

    Todd, B

    2015-01-01

    Risk is a fundamental consideration when designing electronic systems. For most systems a view of risk can assist in setting design objectives, whereas both a qualitative and quantitative understanding of risk is mandatory when considering protection systems. This paper gives an overview of the risks due to stored magnetic and beam energies in high-energy physics, and shows how a risk-based approach can be used to design new systems mitigating these risks, using a lifecycle inspired by IEC 61508. Designing new systems in high-energy physics can be challenging as new and novel techniques are difficult to quantify and predict. This paper shows how the same lifecycle approach can be used in reverse to analyse existing systems, following their operation and first experiences.

  20. Polarisation and precise calibration of the LEP beam energy

    CERN Document Server

    Koutchouk, Jean-Pierre

    2002-01-01

    We report in this article on two issues of precision accelerator physics, performed at the LEP collider, that challenged international collaborations. The first result is an increase of the polarisation degree from an almost vanishing natural level to 50%, opening the way to energy calibration by resonant depolarisation. The second result is a systematic and precise determination of the collider centre-of- mass energy correcting for subtle effects such as the azimuthal variation of the beam energy, the magnet temperature, the effects of parasitic earth currents and terrestrial tides. It resulted in an extremely accurate test of the standard model and set significant constraints on the top quark and Higgs masses. (16 refs).

  1. Method of determining characteristics of a high-energy neutral beam and facility for performing the method

    International Nuclear Information System (INIS)

    Fink, J.H.

    1979-01-01

    The ion beam consisting of H, D, T and He serves to supply energy to a plasma. For monitoring the beam and certain characteristics it is passed through a neutralizing chamber containing a neutralizing gas, and the current, generated in circuits by ions drifting to the wall, is measured. For this purpose the chamber is subdivided into longitudinal or transversal segments being electrically insulated from each other. Each segment is part of a separate current-measuring device, the direction of propagation of the ion beam thus being also susceptible to measurement. (DG) [de

  2. Analytic representation of the backscatter correction factor at the exit of high energy photon beams

    International Nuclear Information System (INIS)

    Kappas, K.; Rosenwald, J.C.

    1991-01-01

    In high-energy X-ray beams, the dose calculated near the exit surface under electronic equilibrium conditions is generally over-estimated since it is derived from measurements performed in water with large thickness of backscattering material. The resulting error depends on a number of parameters such as beam energy, field dimension, thickness of overlying and underlying material. The authors have systematically measured for 4 different energies and for different para- meters and for different combinations of the above parameters, the reduction of dose due to backscatter. This correction is expressed as a multiplicative factor, called 'Backscatter Correction Factor' (BCF). This BCF is larger for lower energies, larger field sizes and larger depths. The BCF has been represented by an analytical expression which involves an exponential function of the backscattering thickness and linear relationships with depth field size and beam quality index. Using this expression, the BCF can be calculated within 0.5% for any conditions in the energy range investigated. (author). 14 refs.; 4 figs.; 3 tabs

  3. LHC MD2877: Beam-beam long range impact on coupling measurements

    CERN Document Server

    Wenninger, Jorg; Carlier, Felix Simon; Coello De Portugal - Martinez Vazquez, Jaime Maria; Fuchsberger, Kajetan; Hostettler, Michi; Persson, Tobias Hakan Bjorn; Tomas Garcia, Rogelio; Valuch, Daniel; Garcia-Tabares Valdivieso, Ana; CERN. Geneva. ATS Department

    2018-01-01

    The LHC is now operating with a tune separation of ∼0.004 in collision. This puts tight constraints on the allowed transverse coupling since a |C−| larger than a fraction of the fractional tune split may lead to beam instabilities. In the last years a new tool based on the ADT used in a similar way as an AC-dipole to excite the beam was developed. The ADT AC-dipole gives coherent oscillations without increasing the beam emittance. These oscillations are analyzed automatically to obtain the value of the coupling. A coupling measurement campaign was done in 2017 and while the correction converged and stayed rather constant over time it was observed that depending on the target bunch and filling scheme the results could vary by Δ|C−| ∼ 0.002. In this MD report we investigated 3 different bunches, one with Long Range Beam-Beam (LRBB) in IPs 1 and 5, one with LRBB in all IPs and one with no LRBB. The results indicate that there are differences in coupling between the bunches experiencing different LR...

  4. Instrumentation for beam radiation and luminosity measurement in the CMS experiment using novel detector technologies

    CERN Document Server

    Guthoff, Moritz

    2016-01-01

    The higher energy and luminosity of the LHC initiated the development of dedicated technologies for radiation monitoring and luminosity measurement. A pixelated luminosity detector counts coincidences in several three layer telescopes of silicon pixel detectors to measure the luminosity for each colliding LHC bunch pair. In addition, charged particle tracking allows to monitor the location of the collision point.The upgraded fast beam conditions monitor measures the particle flux using 24 two pad single crystalline diamond sensors, equipped with a fast front-end ASIC produced in 130 nm CMOS technology. The excellent time resolution is used to separate collision products from machine induced background.A new beam-halo monitor at larger radius exploits Cerenkov light produced by relativistic charged particles in fused quartz crystals to provide direction sensitivity and time resolution to separate incoming and outgoing particles. The back-end electronics of the beam monitoring systems includes dedicated modules...

  5. Non-destructive profile measurement of intensive heavy ion beams; Zerstoerungsfreie Profilmessung intensiver Schwerionenstrahlen

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Frank

    2010-02-08

    Within the framework of the FAIR-project (Facility for Antiproton and Ion Research) at GSI (Helmholtz Center for Heavy Ion Research), high intensity beams from protons to uranium ions with kinetic energies up to 30 AGeV are foreseen. Present GSI-accelerators like the UNILAC and the Heavy Ion Synchrotron (SIS-18) with a magnetic rigidity of 18 Tm will be used as injectors for the future synchrotron (SIS-100). Their beam current will be increased by up to two orders of magnitude. An accurate beam position and beam profile measurement is mandatory for a safe operation of transport sections, in particular in front of production targets (Fragment Separator (FRS)-target, anti p-production-target and Warm Dense Matter (WDM)-targets). Conventional intercepting profile monitors will not withstand the thermal stress of intensive ion beams, particularly for low energy applications or focused beams. For transverse profile determination a non-intercepting Beam Induced Fluorescence (BIF)-monitor was developed, working with residual gas. The BIF-monitor exploits fluorescence light emitted by residual gas molecules after atomic collisions with beam ions. Fluorescence-images were recorded with an image-intensified camera system, and beam profiles were obtained by projecting these images. Within the scope of this dissertation the following topics have been investigated: The photon yield, profile shape and background contribution were determined for different ion species (H{sup +}, S{sup 6+}, Ar{sup 18+}, K{sup +}, Ni{sup 9+}, Xe{sup 48+}, Ta{sup 24+}, Au{sup 65+}, U{sup 73+}), beam energies (7.7 AkeV-750 AMeV), gas pressures (10{sup -6}-3 mbar) and gas species (N{sub 2}, He, Ne, Ar, Kr, Xe). Applying an imaging spectrograph and narrowband 10 nm interference filters, the spectral response was mapped and associated with the corresponding gas transitions. Spectrally resolved beam profiles were also obtained form the spectrographic images. Major results are the light yield showing a

  6. Development of microwave ion source and low energy beam transport system for high current cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Pandit, V.S., E-mail: pandit@vecc.gov.in; Sing Babu, P.; Goswami, A.; Srivastava, S.; Misra, A.; Chatterjee, Mou; Nabhiraj, P.Y.; Yadav, R.C.; Bhattacharya, S.; Roy, S.; Nandi, C.; Pal, G.; Thakur, S.K.

    2013-12-15

    A 2.45 GHz microwave ion source and a low energy beam transport system have been developed to study the high intensity proton beam injection into a 10 MeV, 5 mA compact cyclotron. We have extracted proton beam more than 10 mA at 80 kV as measured by the DCCT after the extraction and a well collimated beam of 7 mA (through 1 cm × 1 cm slit) at the faraday cup 1.5 m away from the source. The transport of protons from the ion source in the presence of H{sub 2}{sup +}, H{sub 3}{sup +} species has been studied using PIC simulations through our transport line which consists of two solenoids. We have also installed a small dipole magnet with similar field as that of the cyclotron along with vacuum chamber, spiral inflector and few diagnostic elements at the end of the beam line. In the preliminary testing of inflection, we achieved 1 mA beam on the faraday cup at the exit of inflector with ∼60% transmission efficiency.

  7. Measuring and recording system for electron beam welding parameters

    International Nuclear Information System (INIS)

    Lobanova, N.G.; Lifshits, M.L.; Efimov, I.I.

    1987-01-01

    The observation possibility during electron beam welding of circular articles with guaranteed clearance of welding bath leading front in joint gap and flare cloud over the bath by means of television monitor is considered. The composition and operation mode of television measuring system for metric characteristics of flare cloud and altitude of welding bath leading front in the clearance are described

  8. Measuring and assessing the physical impact of beam trawling

    NARCIS (Netherlands)

    Depestele, J.; Ivanovic, A.; Esmaelli, M.; Polet, H.; Roche, M.; Summerbell, K.; Teal, L.R.; Vanelslander, B.; O'Neill, F.G.

    2016-01-01

    Beam trawling causes physical disruption of the seabed through contact of the gear components with the sediment and the resuspension of sediment into the water column in the turbulent wake of the gear. To be able to measure and quantify these impacts is important so that gears of reduced impact can

  9. Measuring and monitoring energy poverty

    International Nuclear Information System (INIS)

    Pachauri, Shonali; Spreng, Daniel

    2011-01-01

    This article undertakes a review of alternative measures and indicators of energy poverty targeted to specific audiences and for particular purposes. At the national and international scales there have been some efforts for constructing measures of energy poverty. However, much more needs to be done to develop an internationally consistent measurement framework and to put in place data collection systems that will enable regular reporting. At the programme and project level, indicator systems by necessity need to be designed for specific purposes. Nevertheless, the article proposes that in many instances it is desirable to widen the scope of metrics used for designing and evaluating policies and programmes. In the past, monitoring and evaluation indicators have focused largely on outputs, service delivery or dissemination. Central to the recommendations laid out in the paper is the call for widening the focus of evaluation and necessity to design indicators that adequately assess the needs of beneficiaries and describe the living conditions of families and communities, who are targeted by such programmes and initiatives. - Highlights: ► Consistent measurement frameworks and regular data collection systems on energy poverty are needed. ► Metrics used for designing and evaluating energy access programmes should be widened. ► Indicators that adequately assess needs and describe living conditions of targeted beneficiaries are required.

  10. Effects induced by LHC high energy beam in copper structures

    CERN Document Server

    Peroni, L; Dallocchio, A

    2011-01-01

    This study is performed in order to estimate the damage on copper components due to the impact of a 7 TeV proton beam in the Large Hadron Collider. The case study represents an accidental case consequent to an abnormal release of the beam, in which eight bunches impact directly the copper. The energy delivered on the components is calculated by the FLUKA Team at CERN using their Monte-Carlo code for calculation of particle transport and interactions with matter. The energy maps are used by the authors as input for the structural simulations carried out via the FEM code LS-DYNA. The evolution of the phenomenon is quite similar to what might happen during an explosion. The impacted part of the component reaches extremely high values of pressure and temperature and undergoes changes of state. The sudden increase in pressure originates outgoing shockwaves that, travelling through the component, lead to a substantial density reduction in the impacted part. The energy delivered on the component is sufficient to sev...

  11. High-energy polarized proton beams a modern view

    CERN Document Server

    Hoffstaetter, Georg Heinz

    2006-01-01

    This monograph begins with a review of the basic equations of spin motion in particle accelerators. It then reviews how polarized protons can be accelerated to several tens of GeV using as examples the preaccelerators of HERA, a 6.3 km long cyclic accelerator at DESY / Hamburg. Such techniques have already been used at the AGS of BNL / New York, to accelerate polarized protons to 25 GeV. But for acceleration to energies of several hundred GeV as in RHIC, TEVATRON, HERA, LHC, or a VLHC, new problems can occur which can lead to a significantly diminished beam polarization. For these high energies, it is necessary to look in more detail at the spin motion, and for that the invariant spin field has proved to be a useful tool. This is already widely used for the description of high-energy electron beams that become polarized by the emission of spin-flip synchrotron radiation. It is shown that this field gives rise to an adiabatic invariant of spin-orbit motion and that it defines the maximum time average polarizat...

  12. Measurement of the nucleon structure function using high energy muons

    International Nuclear Information System (INIS)

    Meyers, P.D.

    1983-12-01

    We have measured the inclusive deep inelastic scattering of muons on nucleons in iron using beams of 93 and 215 GeV muons. To perform this measurement, we have built and operated the Multimuon Spectrometer (MMS) in the muon beam at Fermilab. The MMS is a magnetized iron target/spectrometer/calorimeter which provides 5.61 kg/cm 2 of target, 9% momentum resolution on scattered muons, and a direct measure of total hadronic energy with resolution sigma/sub nu/ = 1.4√nu(GeV). In the distributed target, the average beam energies at the interaction are 88.0 and 209 GeV. Using the known form of the radiatively-corrected electromagnetic cross section, we extract the structure function F 2 (x,Q 2 ) with a typical precision of 2% over the range 5 2 2 /c 2 . We compare our measurements to the predictions of lowest order quantum chromodynamics (QCD) and find a best fit value of the QCD scale parameter Λ/sub LO/ = 230 +- 40/sup stat/ +- 80/sup syst/ MeV/c, assuming R = 0 and without applying Fermi motion corrections. Comparing the cross sections at the two beam energies, we measure R = -0.06 +- 0.06/sup stat/ +- 0.11/sup syst/. Our measurements show qualitative agreement with QCD, but quantitative comparison is hampered by phenomenological uncertainties. The experimental situation is quite good, with substantial agreement between our measurements and those of others. 86 references

  13. Design study of low energy beam transport line for ion beams of the post-accelerator at RAON

    Science.gov (United States)

    Lee, Yumi; Kim, Eun-San

    2015-07-01

    Low-energy ions produced by the ion source pass through the focusing and acceleration sections. During this process, the ions accumulate energy and are finally transported to the apparatus that utilizes them for a specific purpose. Thus, in order to increase the transmission efficiency of the ion beams, the low energy beam transport (LEBT) system must minimize the beam loss and the emittance growth. The LEBT system is designed and optimized to transmit 132Sn16+ and 58Ni8+ beams of the post-accelerator at RAON that is the accelerator complex for the rare isotope science. The post-accelerator LEBT line comprises solenoids and electrostatic quadrupoles for transverse focusing and a multi-harmonic buncher for longitudinal focusing. This paper presents the results of the optical design and beam tracking for the post-accelerator LEBT obtained by using TraceWIN and TRACK codes.

  14. Electron density measurements during ion beam transport on Gamble II

    International Nuclear Information System (INIS)

    Weber, B.V.; Hinshelwood, D.D.; Neri, J.M.; Ottinger, P.F.; Rose, D.V.; Stephanakis, S.J.; Young, F.C.

    1999-01-01

    High-sensitivity laser interferometry was used to measure the electron density created when an intense proton beam (100 kA, 1 MeV, 50 ns) from the Gamble II generator was transported through low-pressure gas as part of a project investigating Self-Pinched Transport (SPT) of intense ion beams. This measurement is non-perturbing and sufficiently quantitative to allow benchmarking of codes (particularly IPROP) used to model beam-gas interaction and ion-beam transport. Very high phase sensitivity is required for this measurement. For example, a 100-kA, 1-MeV, 10-cm-radius proton beam with uniform current density has a line-integrated proton density equal to n b L = 3 x 10 13 cm -2 . An equal electron line-density, n e L = n b L, (expected for transport in vacuum) will be detected as a phase shift of the 1.064 microm laser beam of only 0.05degree, or an optical path change of 1.4 x 10 -4 waves (about the size of a hydrogen atom). The time-history of the line-integrated electron density, measured across a diameter of the transport chamber at 43 cm from the input aperture, starts with the proton arrival time and decays differently depending on the gas pressure. The gas conditions included vacuum (10 -4 Torr air), 30 to 220 mTorr He, and 1 Torr air. The measured densities vary by three orders of magnitude, from 10 13 to 10 16 cm -2 for the range of gas pressures investigated. In vacuum, the measured electron densities indicate only co-moving electrons (n e L approximately n b L). In He, when the gas pressure is sufficient for ionization by beam particles and SPT is observed, n e L increases to about 10 n b L. At even higher pressures where electrons contribute to ionization, even higher electron densities are observed with an ionization fraction of about 2%. The diagnostic technique as used on the SPT experiment will be described and a summary of the results will be given. The measurements are in reasonable agreement with theoretical predictions from the IPROP code

  15. A portable Compton spectrometer for clinical X-ray beams in the energy range 20-150 keV

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, A.A. [Departamento de Fisica, Pontificia Universidade Catolica de Sao Paulo (PUC-SP), Rua Marques de Paranagua, 111-01303-050 Sao Paulo, SP (Brazil); Linke, A. [Instituto de Fisica-Universidade de Sao Paulo, Rua do Matao, 187-Travessa R-05508-900 Sao Paulo, SP (Brazil); Yoshimura, E.M., E-mail: e.yoshimura@dfn.if.usp.b [Instituto de Fisica-Universidade de Sao Paulo, Rua do Matao, 187-Travessa R-05508-900 Sao Paulo, SP (Brazil); Terini, R.A., E-mail: rterini@pucsp.b [Departamento de Fisica, Pontificia Universidade Catolica de Sao Paulo (PUC-SP), Rua Marques de Paranagua, 111-01303-050 Sao Paulo, SP (Brazil); Instituto de Eletrotecnica e Energia-Universidade de Sao Paulo, Av. Prof. Luciano Gualberto, 1289-05508-900 Sao Paulo, SP (Brazil); Herdade, S.B., E-mail: sherdade@iee.usp.b [Instituto de Fisica-Universidade de Sao Paulo, Rua do Matao, 187-Travessa R-05508-900 Sao Paulo, SP (Brazil); Instituto de Eletrotecnica e Energia-Universidade de Sao Paulo, Av. Prof. Luciano Gualberto, 1289-05508-900 Sao Paulo, SP (Brazil)

    2011-02-15

    Primary beam spectra were obtained for an X-ray industrial equipment (40-150 kV), and for a clinical mammography apparatus (25-35 kV) from beams scattered at angles close to 90{sup o}, measured with a CdTe Compton spectrometer. Actual scattering angles were determined from the Compton energy shift of characteristic X-rays or spectra end-point energy. Evaluated contribution of coherent scattering amounts to more than 15% of fluence in mammographic beams. This technique can be used in clinical environments.

  16. A portable Compton spectrometer for clinical X-ray beams in the energy range 20-150 keV

    International Nuclear Information System (INIS)

    Vieira, A.A.; Linke, A.; Yoshimura, E.M.; Terini, R.A.; Herdade, S.B.

    2011-01-01

    Primary beam spectra were obtained for an X-ray industrial equipment (40-150 kV), and for a clinical mammography apparatus (25-35 kV) from beams scattered at angles close to 90 o , measured with a CdTe Compton spectrometer. Actual scattering angles were determined from the Compton energy shift of characteristic X-rays or spectra end-point energy. Evaluated contribution of coherent scattering amounts to more than 15% of fluence in mammographic beams. This technique can be used in clinical environments.

  17. The effect of high energy ion beam analysis on D trapping in W

    Science.gov (United States)

    Finlay, T. J.; Davis, J. W.; Schwarz-Selinger, T.; Haasz, A. A.

    2017-12-01

    High energy ion beam analyses (IBA) are invaluable for measuring concentration depth profiles of light elements in solid materials, and important in the study of fusion fuel retention in tokamaks. Polycrystalline W specimens were implanted at 300 and 500 K, 5–10 × 1023 D m‑2 fluence, with deuterium-only and simultaneous D-3%He ion beams. Selected specimens were analysed by elastic recoil detection analysis (ERDA) and/or nuclear reaction analysis (NRA). All specimens were measured by thermal desorption spectroscopy (TDS). The D TDS spectra show an extra peak at 900–1000 K following ERDA and/or NRA measurements. The peak height appears to correlate with the amount of D initially trapped beyond the calculated IBA probe beam peak damage depth. Similar to pre-implantation damage scenarios, the IBA probe beam creates empty high energy traps which later retrap D atoms during TDS heating, which is supported by modelling experimental results using the Tritium Migration Analysis Program.

  18. Beamed Energy Propulsion by Means of Target Ablation

    International Nuclear Information System (INIS)

    Rosenberg, Benjamin A.

    2004-01-01

    This paper describes hundreds of pendulum tests examining the beamed energy conversion efficiency of different metal targets coated with multiple liquid enhancers. Preliminary testing used a local laser with photographic paper targets, with no liquid, water, canola oil, or methanol additives. Laboratory experimentation was completed at Wright-Patterson AFB using a high-powered laser, and ballistic pendulums of aluminum, titanium, or copper. Dry targets, and those coated with water, methanol and oil were repeatedly tested in laboratory conditions. Results were recorded on several high-speed digital video cameras, and the conversion efficiency was calculated. Paper airplanes successfully launched using BEP were likewise recorded

  19. Replacement of chemical rocket launchers by beamed energy propulsion.

    Science.gov (United States)

    Fukunari, Masafumi; Arnault, Anthony; Yamaguchi, Toshikazu; Komurasaki, Kimiya

    2014-11-01

    Microwave Rocket is a beamed energy propulsion system that is expected to reach space at drastically lower cost. This cost reduction is estimated by replacing the first-stage engine and solid rocket boosters of the Japanese H-IIB rocket with Microwave Rocket, using a recently developed thrust model in which thrust is generated through repetitively pulsed microwave detonation with a reed-valve air-breathing system. Results show that Microwave Rocket trajectory, in terms of velocity versus altitude, can be designed similarly to the current H-IIB first stage trajectory. Moreover, the payload ratio can be increased by 450%, resulting in launch-cost reduction of 74%.

  20. Combined e-beam lithography using different energies

    Czech Academy of Sciences Publication Activity Database

    Krátký, Stanislav; Kolařík, Vladimír; Horáček, Miroslav; Meluzín, Petr; Král, Stanislav

    2017-01-01

    Roč. 177, JUN (2017), s. 30-34 ISSN 0167-9317 R&D Projects: GA TA ČR TE01020233; GA MŠk(CZ) LO1212; GA MŠk ED0017/01/01 Institutional support: RVO:68081731 Keywords : grayscale e-beam lithography * mix and match process * absorbed energy density * resist sensitivity * micro-optical elements Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Nano-processes (applications on nano-scale) Impact factor: 1.806, year: 2016

  1. Proton beam writing using the high energy ion nanoprobe LIPSION

    International Nuclear Information System (INIS)

    Menzel, F.; Spemann, D.; Lenzner, J.; Vogt, J.; Butz, T.

    2005-01-01

    Proton beam writing (PBW) is a very unique technique capable of the direct creation of three dimensional structures with a very high aspect ratio. Since the high energy ion nanoprobe LIPSION has a very high spatial resolution and is therefore well suited for the creation of structures in the micrometre range or below, it is planned to establish the PBW technique at the University of Leipzig. The results of the first proton beam writing experiments at the LIPSION nanoprobe are presented in this article. Structures with high aspect ratio and smooth side walls with an edge definition of ∼0.2 μm were created in negative SU-8 photo resist using 2.25 MeV protons. Furthermore, investigations were carried out concerning the mechanical stability of single free standing walls in order to collect information for the targeted production of samples with smaller feature sizes in the submicrometre range. Up to now, wall widths down to 1.5 μm were achieved. However, smaller feature sizes could not be obtained due to beam spot fluctuations which enlarge the wall width by a factor of three. Self-supported structures were produced using 2.25 MeV protons and subsequently 1.5 MeV helium ions demonstrating the stability and accuracy of these real three dimensional structures. In addition, different methods for online dose normalization were tested showing that ionoluminescence is the most suitable method for this purpose

  2. Device for the collimation of a high-energy beam, in particular a X-ray beam

    International Nuclear Information System (INIS)

    Peyser, L.F.

    1976-01-01

    The design of apertures made of radiation-absorbing material intended for limiting an aperture for a radiation beam of high energy, in particular an X-ray beam is claimed. The apertures are shaped as trapezoids, are held movably, and are adjustable by means of a control device. (UWI) [de

  3. Measurements of beam-ion confinement during tangential beam-driven instabilities in PBX [Princeton Beta Experiment

    International Nuclear Information System (INIS)

    Heidbrink, W.W.; Kaita, R.; Takahashi, H.; Gammel, G.; Hammett, G.W.; Kaye, S.

    1987-01-01

    During tangential injection of neutral beams into low density tokamak plasmas with β > 1% in the Princeton Beta Experiment (PBX), instabilities are observed that degrade the confinement of beam ions. Neutron, charge-exchange, and diamagnetic loop measurements are examined in order to identify the mechanism or mechanisms responsible for the beam-ion transport. The data suggest a resonant interaction between the instabilities and the parallel energetic beam ions. Evidence for some nonresonant transport also exists

  4. The software for the CERN LEP beam orbit measurement system

    International Nuclear Information System (INIS)

    Morpurgo, G.

    1992-01-01

    The Beam Orbit Measurement (BOM) system of LEP consists of 504 pickups, distributed all around the accelerator, that are capable of measuring the positions of the two beams. Their activity has to be synchronized, and the data produced by them have to be collected together, for example to form a 'closed orbit measurement' or a 'trajectory measurement'. On the user side, several clients can access simultaneously the results from this instrument. An automatic acquisition mode, and an 'on request' one, can run in parallel. This results in a very flexible and powerful system. The functionality of the BOM system is fully described, as well as the structure of the software processes which constitute the system, and their interconnections. Problems solved during the implementation are emphasized. (author)

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

    OpenAIRE

    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 up...

  6. Development and Applications of Residual Stress Measurements Using Neutron Beams

    OpenAIRE

    ABRIOLA S. A.; BALAGUROV A.; BASHIR J.; DAS A.; EDWARDS L.; GNAEUPEL-HEROLD T.; GOH B.; IONITA I.; MIKULA P.; OHMS Carsten; PELD N.; SCHNEIDER Rainer; SUTIARSO S.; TOROK G.; VENTER A.

    2012-01-01

    The deep penetration and selective absorption of neutrons make them a powerful tool in nondestructive testing of materials with large samples or objects. Residual stress formed in a material during manufacturing, welding, utilization or repairs can be measured by means of neutron diffraction. In fact, neutron diffraction is the only non-destructive testing method, which can facilitate 3-D mapping of residual stress in a bulk component. Stress measurement using neutron beams is a technique ...

  7. Measurement of the pion form factor at higher energies

    Energy Technology Data Exchange (ETDEWEB)

    Mack, D.J. [CEBAF, Newport News, VA (United States)

    1994-04-01

    One of the strongest arguments for increasing the nominal CEBAF beam energy to equal or exceed 6 GeV is that one would be able to make quality high Q{sup 2} measurements of the charged pion form factor.

  8. Determination of the neutron energy and spatial distributions of the neutron beam from the TSR-II in the large beam shield

    International Nuclear Information System (INIS)

    Clifford, C.E.; Muckenthaler, F.J.

    1976-01-01

    The TSR-II reactor of the ORNL Tower Shielding Facility has recently been relocated within a new, fixed shield. A principal feature of the new shield is a beam port of considerably larger area than that of its predecessor. The usable neutron flux has thereby been increased by a factor of approximately 200. The bare beam neutron spectrum behind the new shield has been experimentally determined over the energy range from 0.8 to 16 MeV. A high level of fission product gamma ray background prevented measurement of bare beam spectra below 0.8 MeV, however neutron spectra in the energy range from 8 keV to 1.4 MeV were obtained for two simple, calculable shielding configurations. Also measured in the present work were weighted integral flux distributions and fast neutron dose rates

  9. Carbon filament beam profile monitor for high energy proton-antiproton storage rings

    International Nuclear Information System (INIS)

    Evans, L.R.; Shafer, R.E.

    1979-01-01

    The measurement of the evolution of the transverse profile of the stored beams in high energy proton storage rings such as the p-anti p colliders at CERN and at FNAL is of considerable importance. In the present note, a simple monitor is discussed which will allow almost non-destructive measurement of the profile of each individual proton and antiproton bunch separately. It is based on the flying wire technique first used at CEA and more recently at the CPS. A fine carbon filament is passed quickly through the beam, acting as a target for secondary particle production. The flux of secondary particles is measured by two scintillator telescopes, one for protons and one for antiprotons, having an angular acceptance between 30 and 100 mrad. Measurements of secondary particle production performed at FNAL in this angular range show that a very respectable flux can be expected

  10. Second crossover energy of insulating materials using stationary electron beam under normal incidence

    Energy Technology Data Exchange (ETDEWEB)

    Rau, E.I. [Institute of Microelectronics Technology of Russian Academy of Science, 142432 Chernogolovka, Moscow District (Russian Federation)], E-mail: rau@phys.msu.ru; Fakhfakh, S. [LaMaCop, Faculte des Sciences, Route Soukra km 3, BP 802, CP 3018 Sfax (Tunisia); Andrianov, M.V.; Evstafeva, E.N. [Institute of Microelectronics Technology of Russian Academy of Science, 142432 Chernogolovka, Moscow District (Russian Federation); Jbara, O. [UTAP/LASSI, EA 3802, Faculte des Sciences, BP 1039, 51687 Reims Cedex 2 (France)], E-mail: omar.jbara@univ-reims.fr; Rondot, S.; Mouze, D. [UTAP/LASSI, EA 3802, Faculte des Sciences, BP 1039, 51687 Reims Cedex 2 (France)

    2008-03-15

    The purpose of this paper is to give some aspects of charging effects on dielectric materials submitted to continuous electron beam irradiation in a scanning electron microscope (SEM). When the dielectric is irradiated continuously, the so-called total yield approach (TYA) used to predict the sign of the charge appeared on electron irradiated insulators fails because the charge accumulated in the dielectric interferes with the electrons emission processes. Based on previous experimental and theoretical works found in the literature, an analysis of the evolution of the electron yield curves {sigma} = f(E{sub 0}) of insulators during irradiation is given. The aim of this work is firstly to determine experimentally the second crossover energy E{sub 2C} under continuous electron irradiation (charging conditions) and secondly to demonstrate that the charge balance occurs at this beam energy and not at E{sub 2} the energy deduced from non-charging conditions (pulse primary electron beam experiments) as commonly asserted. It is however possible to apply the TYA by substituting the critical energy E{sub 2} for E{sub 2C}. The experimental procedure is based on simultaneous time dependent measurements of surface potential, leakage current and displacement current. The study underlines the difference between the landing energy of primary electrons E{sub L} at the steady state and the second crossover energy, E{sub 2C}, for charged samples. Some preliminary results are also obtained concerning the influence of the incident beam density on the energy E{sub 2C}. The samples used for this study are PMMA, polycrystalline silicone dioxide (p-SiO{sub 2}), polycrystalline alumina (p-Al{sub 2}O{sub 3}) and soda lime glass (SLG)

  11. Second crossover energy of insulating materials using stationary electron beam under normal incidence

    International Nuclear Information System (INIS)

    Rau, E.I.; Fakhfakh, S.; Andrianov, M.V.; Evstafeva, E.N.; Jbara, O.; Rondot, S.; Mouze, D.

    2008-01-01

    The purpose of this paper is to give some aspects of charging effects on dielectric materials submitted to continuous electron beam irradiation in a scanning electron microscope (SEM). When the dielectric is irradiated continuously, the so-called total yield approach (TYA) used to predict the sign of the charge appeared on electron irradiated insulators fails because the charge accumulated in the dielectric interferes with the electrons emission processes. Based on previous experimental and theoretical works found in the literature, an analysis of the evolution of the electron yield curves σ = f(E 0 ) of insulators during irradiation is given. The aim of this work is firstly to determine experimentally the second crossover energy E 2C under continuous electron irradiation (charging conditions) and secondly to demonstrate that the charge balance occurs at this beam energy and not at E 2 the energy deduced from non-charging conditions (pulse primary electron beam experiments) as commonly asserted. It is however possible to apply the TYA by substituting the critical energy E 2 for E 2C . The experimental procedure is based on simultaneous time dependent measurements of surface potential, leakage current and displacement current. The study underlines the difference between the landing energy of primary electrons E L at the steady state and the second crossover energy, E 2C , for charged samples. Some preliminary results are also obtained concerning the influence of the incident beam density on the energy E 2C . The samples used for this study are PMMA, polycrystalline silicone dioxide (p-SiO 2 ), polycrystalline alumina (p-Al 2 O 3 ) and soda lime glass (SLG)

  12. High energy high intensity coherent photon beam for the SSC

    International Nuclear Information System (INIS)

    Tannenbaum, M.J.

    1984-01-01

    What is proposed for the 20 TeV protons hitting a fixed target is to make a tertiary electron beam similar to that which is the basis of the tagged photon beam at Fermilab. Briefly, a zero degree neutral beam is formed by sweeping out the primary proton beam and any secondary charged particles. Then the photons, from the decay of π 0 in the neutral beam, are converted to e + e - pairs in a lead converter and a high quality electron beam is formed. This beam is brought to the target area where it is converted to a photon beam by Bremsstrahlung in a radiator

  13. Loss of Energy Concentration in Nonlinear Evolution Beam Equations

    Science.gov (United States)

    Garrione, Maurizio; Gazzola, Filippo

    2017-12-01

    Motivated by the oscillations that were seen at the Tacoma Narrows Bridge, we introduce the notion of solutions with a prevailing mode for the nonlinear evolution beam equation u_{tt} + u_{xxxx} + f(u)= g(x, t) in bounded space-time intervals. We give a new definition of instability for these particular solutions, based on the loss of energy concentration on their prevailing mode. We distinguish between two different forms of energy transfer, one physiological (unavoidable and depending on the nonlinearity) and one due to the insurgence of instability. We then prove a theoretical result allowing to reduce the study of this kind of infinite-dimensional stability to that of a finite-dimensional approximation. With this background, we study the occurrence of instability for three different kinds of nonlinearities f and for some forcing terms g, highlighting some of their structural properties and performing some numerical simulations.

  14. Beam profile measurement of ES-200 using secondary electron emission monitor

    Directory of Open Access Journals (Sweden)

    E Ebrahimi Basabi

    2015-09-01

    Full Text Available Up to now, different designs have been introduced for measurement beam profile accelerators. Secondary electron emission monitors (SEM are one of these devices which have been used for this purpose. In this work, a SEM has been constructed to measure beam profile of ES-200 accelerator, a proton electrostatic accelerator which is installed at SBU. Profile grid for both planes designed with 16 wires which are insulated relative to each other. The particles with maximum energy of 200 keV and maximum current of 400 μA are stopped in copper wires. Each of the wires has an individual current-to-voltage amplifier. With a multiplexer, the analogue values are transported to an ADC. The ADCs are read out by a microcontroller and finally profile of beam shows by a user interface program

  15. Monte Carlo dose calculation improvements for low energy electron beams using eMC

    International Nuclear Information System (INIS)

    Fix, Michael K; Frei, Daniel; Volken, Werner; Born, Ernst J; Manser, Peter; Neuenschwander, Hans

    2010-01-01

    The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm 2 of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d max and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm 2 at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose calculation

  16. Monte Carlo dose calculation improvements for low energy electron beams using eMC.

    Science.gov (United States)

    Fix, Michael K; Frei, Daniel; Volken, Werner; Neuenschwander, Hans; Born, Ernst J; Manser, Peter

    2010-08-21

    The electron Monte Carlo (eMC) dose calculation algorithm in Eclipse (Varian Medical Systems) is based on the macro MC method and is able to predict dose distributions for high energy electron beams with high accuracy. However, there are limitations for low energy electron beams. This work aims to improve the accuracy of the dose calculation using eMC for 4 and 6 MeV electron beams of Varian linear accelerators. Improvements implemented into the eMC include (1) improved determination of the initial electron energy spectrum by increased resolution of mono-energetic depth dose curves used during beam configuration; (2) inclusion of all the scrapers of the applicator in the beam model; (3) reduction of the maximum size of the sphere to be selected within the macro MC transport when the energy of the incident electron is below certain thresholds. The impact of these changes in eMC is investigated by comparing calculated dose distributions for 4 and 6 MeV electron beams at source to surface distance (SSD) of 100 and 110 cm with applicators ranging from 6 x 6 to 25 x 25 cm(2) of a Varian Clinac 2300C/D with the corresponding measurements. Dose differences between calculated and measured absolute depth dose curves are reduced from 6% to less than 1.5% for both energies and all applicators considered at SSD of 100 cm. Using the original eMC implementation, absolute dose profiles at depths of 1 cm, d(max) and R50 in water lead to dose differences of up to 8% for applicators larger than 15 x 15 cm(2) at SSD 100 cm. Those differences are now reduced to less than 2% for all dose profiles investigated when the improved version of eMC is used. At SSD of 110 cm the dose difference for the original eMC version is even more pronounced and can be larger than 10%. Those differences are reduced to within 2% or 2 mm with the improved version of eMC. In this work several enhancements were made in the eMC algorithm leading to significant improvements in the accuracy of the dose

  17. Radiation processing of natural polymers using low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2004-01-01

    Radiation processing is widely used in Japan and the economic scale of radiation application amounted to about 71 b$ (ratio relative to GDP: 1.7%) in total. It consisted of 60 b$ (85%) in industry, 10 b$ (14%) in medicine and 1 b$ (1%) in agriculture. Irradiation using gamma-ray from 60 Co and electron beam is commercially used for the sterilization and modification of materials. Utilization of natural polymers by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan, sodium alginate, carrageenan, cellulose, pectin were easily degraded by irradiation and induced various kinds of biological activities, i.e. anti-bacterial activity, elicitor activity, plant growth promotion, suppression of environmental stress on plants. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. Low energy electron beam (EB) irradiation has a variety of applications and good safety. A self-shielded low energy electron accelerator system needs an initial investment much lower than a 60 Co facility. It was demonstrated that the liquid sample irradiation system using low energy EB was effective not only for the preparation of degraded polysaccharides but also for radiation vulcanization of natural rubber latex (RVNRL). Some carbohydrate derivatives, carboxymethylcellulose (CMC), carboxymethyl-starch and carboxymethyl-chitin/chitosan, can be crosslinked under certain radiation condition and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  18. Production of low axial energy spread ion beams with multicusp sources

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Yung -Hee Y. [Univ. of California, Berkeley, CA (United States)

    1998-05-01

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution.

  19. Production of low axial energy spread ion beams with multicusp sources

    International Nuclear Information System (INIS)

    Lee, Y.H.Y.

    1998-05-01

    Multicusp ion sources are capable of producing ions with low axial energy spread which are necessary in applications such as: ion projection lithography (IPL) and focused ion beams for the next generation lithographic tools and nuclear science experiments such as radioactive ion beam production. The axial ion energy spread for multicusp source is approximately 6 eV which is too large for IPL and radioactive ion beam applications. The addition of a magnetic filter which consists of a pair of permanent magnets to the multicusp source reduces the energy spread considerably. The reduction is due to the improvement in the uniformity of the axial plasma potential distribution in the discharge region. Axial ion energy spread of the filament driven ion source has been measured using three different techniques. In all cases, it was found to be less than 2 eV. Energy spread of the radio frequency (RF) driven source has also been explored, and it was found to be less than 3 eV with the proper RF-shielding. A new multicusp source configuration has been designed and constructed to further reduce the energy spread. To achieve a more uniform axial plasma potential distribution, a cylindrical magnetic filter has been designed and constructed for a 2-cm-diameter source. This new source configuration, the co-axial source, is new in its kind. The energy spread in this source has been measured to be a record low of 0.6 eV. Because of the novelty of this device, some plasma parameters inside the source have been studied. Langmuir probe has been used to measure the plasma potential, the electron temperature and the density distribution

  20. Beam collimation and energy spectrum compression of laser-accelerated proton beams using solenoid field and RF cavity

    International Nuclear Information System (INIS)

    Teng, J.; Gu, Y.Q.; Zhu, B.; Hong, W.; Zhao, Z.Q.; Zhou, W.M.; Cao, L.F.

    2013-01-01

    This paper presents a new method of laser produced proton beam collimation and spectrum compression using a combination of a solenoid field and a RF cavity. The solenoid collects laser-driven protons efficiently within an angle that is smaller than 12 degrees because it is mounted few millimeters from the target, and collimates protons with energies around 2.3 MeV. The collimated proton beam then passes through a RF cavity to allow compression of the spectrum. Particle-in-cell (PIC) simulations demonstrate the proton beam transport in the solenoid and RF electric fields. Excellent energy compression and collection efficiency of protons are presented. This method for proton beam optimization is suitable for high repetition-rate laser acceleration proton beams, which could be used as an injector for a conventional proton accelerator

  1. Beam collimation and energy spectrum compression of laser-accelerated proton beams using solenoid field and RF cavity

    Science.gov (United States)

    Teng, J.; Gu, Y. Q.; Zhu, B.; Hong, W.; Zhao, Z. Q.; Zhou, W. M.; Cao, L. F.

    2013-11-01

    This paper presents a new method of laser produced proton beam collimation and spectrum compression using a combination of a solenoid field and a RF cavity. The solenoid collects laser-driven protons efficiently within an angle that is smaller than 12 degrees because it is mounted few millimeters from the target, and collimates protons with energies around 2.3 MeV. The collimated proton beam then passes through a RF cavity to allow compression of the spectrum. Particle-in-cell (PIC) simulations demonstrate the proton beam transport in the solenoid and RF electric fields. Excellent energy compression and collection efficiency of protons are presented. This method for proton beam optimization is suitable for high repetition-rate laser acceleration proton beams, which could be used as an injector for a conventional proton accelerator.

  2. Measurement of in-phantom neutron flux and gamma dose in Tehran research reactor boron neutron capture therapy beam line.

    Science.gov (United States)

    Bavarnegin, Elham; Sadremomtaz, Alireza; Khalafi, Hossein; Kasesaz, Yaser

    2016-01-01

    Determination of in-phantom quality factors of Tehran research reactor (TRR) boron neutron capture therapy (BNCT) beam. The doses from thermal neutron reactions with 14N and 10B are calculated by kinetic energy released per unit mass approach, after measuring thermal neutron flux using neutron activation technique. Gamma dose is measured using TLD-700 dosimeter. Different dose components have been measured in a head phantom which has been designed and constructed for BNCT purpose in TRR. Different in-phantom beam quality factors have also been determined. This study demonstrates that the TRR BNCT beam line has potential for treatment of superficial tumors.

  3. Influence of the Integral Quality Monitor transmission detector on high energy photon beams. A multi-centre study

    Energy Technology Data Exchange (ETDEWEB)

    Casar, Bozidar [Institute of Oncology, Ljubljana (Slovenia). Dept. of Radiation Physics; Pasler, Marlies [Lake Constance Radiation Oncology Center, Singen and Friedrichshafen (Germany); Wegener, Sonja [Wuerzburg Univ. (Germany). Dept. of Radiation Oncology; and others

    2017-10-01

    The influence of the Integral Quality Monitor (IQM) transmission detector on photon beam properties was evaluated in a preclinical phase, using data from nine participating centres: (i) the change of beam quality (beam hardening), (ii) the influence on surface dose, and (iii) the attenuation of the IQM detector. For 6 different nominal photon energies (4 standard, 2 FFF) and square field sizes from 1 x 1 cm{sup 2} to 20 x 20 cm{sup 2}, the effect of IQM on beam quality was assessed from the PDD{sub 20,10} values obtained from the percentage dose depth (PDD) curves, measured with and without IQM in the beam path. The change in surface dose with/without IQM was assessed for all available energies and field sizes from 4 x 4 cm{sup 2} to 20 x 20 cm{sup 2}. The transmission factor was calculated by means of measured absorbed dose at 10 cm depth for all available energies and field sizes. (i) A small (0.11-0.53%) yet statistically significant beam hardening effect was observed, depending on photon beam energy. (ii) The increase in surface dose correlated with field size (p < 0.01) for all photon energies except for 18 MV. The change in surface dose was smaller than 3.3% in all cases except for the 20 x 20 cm{sup 2} field and 10 MV FFF beam, where it reached 8.1%. (iii) For standard beams, transmission of the IQM showed a weak dependence on the field size, and a pronounced dependence on the beam energy (0.9412 for 6 MV to 0.9578 for 18 MV and 0.9440 for 6 MV FFF; 0.9533 for 10 MV FFF). The effects of the IQM detector on photon beam properties were found to be small yet statistically significant. The magnitudes of changes which were found justify treating IQM either as tray factors within the treatment planning system (TPS) for a particular energy or alternatively as modified outputs for specific beam energy of linear accelerators, which eases the introduction of the IQM into clinical practice.

  4. In-phantom spectra and dose distributions from a high-energy neutron therapy beam

    Energy Technology Data Exchange (ETDEWEB)

    Benck, S. E-mail: benck@fynu.ucl.ac.be; D' Errico, F.; Denis, J.-M.; Meulders, J.-P.; Nath, R.; Pitcher, E.J

    2002-01-01

    In radiotherapy with external beams, healthy tissues surrounding the target volumes are inevitably irradiated. In the case of neutron therapy, the estimation of dose to the organs surrounding the target volume is particularly challenging, because of the varying contributions from primary and secondary neutrons and photons of different energies. The neutron doses to tissues surrounding the target volume at the Louvain-la-Neuve (LLN) facility were investigated in this work. At LLN, primary neutrons have a broad spectrum with a mean energy of about 30 MeV. The transport of a 10x10 cm{sup 2} beam through a water phantom was simulated by means of the Monte Carlo code MCNPX. Distributions of energy-differential values of neutron fluence, kerma and kerma equivalent were estimated at different locations in a water phantom. The evolution of neutron dose and dose equivalent inside the phantom was deduced. Measurements of absorbed dose and of dose equivalent were then carried out in a water phantom using an ionization chamber and superheated drop detectors (SDDs). On the beam axis, the calculations agreed well with the ionization chamber data, but disagreed significantly from the SDD data due to the detector's under-response to neutrons above 20 MeV. Off the beam axis, the calculated absorbed doses were significantly lower than the ionization chamber readings, since gamma fields were not accounted for. The calculated data are doses from neutron-induced charge particles, and these agreed with the values measured by the photon-insensitive SDDs. When exposed to the degraded spectra off the beam axis, the SDD offered reliable estimates of the neutron dose equivalent.

  5. Measurement of the SMC muon beam polarisation using the asymmetry in the elastic scattering off polarised electrons

    CERN Document Server

    Adams, D; Adeva, B; Akdogan, T; Arik, E; Arvidson, A; Badelek, B; Bardin, G; Baum, G; Berglund, P; Betev, L; Birsa, R; Björkholm, P; Bonner, B E; De Botton, N R; Boutemeur, M; Bradamante, Franco; Bravar, A; Bressan, A; Bültmann, S; Burtin, E; Cavata, C; Clocchiatti, M; Crabb, D; Cranshaw, J; Çuhadar-Dönszelmann, T; Dalla Torre, S; Van Dantzig, R; Derro, B R; Deshpande, A A; Dhawan, S K; Dulya, C M; Dyring, A; Eichblatt, S; Faivre, Jean-Claude; Fasching, D; Feinstein, F; Fernández, C; Forthmann, S; Frois, Bernard; Gallas, A; Garzón, J A; Gatignon, L; Gaussiran, T; Gilly, H; Giorgi, M A; von Goeler, E; Görtz, S; Golutvin, I A; Gracia, G; De Groot, N; Grosse-Perdekamp, M; Haft, K; Von Harrach, D; Hasegawa, T; Hautle, P; Hayashi, N; Heusch, C A; Horikawa, N; Hughes, V W; Igo, G; Ishimoto, S; Iwata, T; Kabuss, E M; Kageya, T; Karev, A G; Kessler, H J; Ketel, T; Kiryluk, J; Kiryushin, Yu T; Kishi, A; Kiselev, Yu F; Klostermann, L; Krämer, Dietrich; Krivokhizhin, V G; Kröger, W; Kukhtin, V V; Kurek, K; Kyynäräinen, J; Lamanna, M; Landgraf, U; Le Goff, J M; Lehár, F; de Lesquen, A; Lichtenstadt, J; Lindqvist, T; Litmaath, M; Loewe, M; Magnon, A; Mallot, G K; Marie, F; Martin, A; Martino, J; Matsuda, T; Mayes, B W; McCarthy, J S; Medved, K S; Meyer, W T; Van Middelkoop, G; Miller, D; Miyachi, Y; Mori, K; Moromisato, J H; Nagaitsev, A P; Nassalski, J P; Naumann, Lutz; Niinikoski, T O; Oberski, J; Ogawa, A; Ozben, C; Pereira, H; Perrot-Kunne, F; Peshekhonov, V D; Piegaia, R; Pinsky, L; Platchkov, S K; Pló, M; Pose, D; Postma, H; Pretz, J; Pussieux, T; Rädel, G; Rijllart, A; Reicherz, G; Roberts, J B; Rock, S E; Rodríguez, M; Rondio, Ewa; Ropelewski, Leszek; Sabo, I; Saborido, J; Sandacz, A; Savin, I A; Schiavon, R P; Schiller, A; Schüler, K P; Seitz, R; Semertzidis, Y K; Sergeev, S; Shanahan, P; Sichtermann, E P; Simeoni, F; Smirnov, G I; Staude, A; Steinmetz, A; Stiegler, U; Stuhrmann, H B; Szleper, M; Tessarotto, F; Thers, D; Tlaczala, W; Tripet, A; Ünel, G; Velasco, M; Vogt, J; Voss, Rüdiger; Whitten, C; Windmolders, R; Willumeit, R; Wislicki, W; Witzmann, A; Ylöstalo, J; Zanetti, A M; Zaremba, K; Zamiatin, N I; Zhao, J

    2000-01-01

    A muon beam polarimeter was built for the SMC experiment at the CERN SPS, for beam energies of 100 and 190 GeV. The beam polarisation is determined from the asymmetry in the elastic scattering off the polarised electrons of a ferromagnetic target whose magnetisation is periodically reversed. At muon energies of 100 and 190~GeV the measured polarisation is $P_{\\mu}=-0.80 \\pm 0.03 (stat.)\\pm 0.02 (syst.)$ and $P_{\\mu}=-0.797 \\pm 0.011 (stat.)\\pm 0.012 (syst.)$, respectively. These results agree with measurements of the beam polarisation using a shape analysis of the decay positron energy spectrum.

  6. Energy monitoring device for 1.5-2.4 MeV electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Fuochi, P.G., E-mail: fuochi@isof.cnr.i [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Lavalle, M.; Martelli, A. [CNR-ISOF, Via P. Gobetti 101, I-40129 Bologna (Italy); Kovacs, A. [Institute of Isotopes, HAS, P.O.Box 77, H-1525 Budapest (Hungary); Mehta, K. [Arbeiterstrandbad Strasse 72, Vienna, A-1210 (Austria); Kuntz, F.; Plumeri, S. [Aerial, Parc d' Innovation Rue Laurent Fries F-67400 Illkirch (France)

    2010-03-11

    An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

  7. Energy monitoring device for 1.5-2.4 MeV electron beams

    Science.gov (United States)

    Fuochi, P. G.; Lavalle, M.; Martelli, A.; Kovács, A.; Mehta, K.; Kuntz, F.; Plumeri, S.

    2010-03-01

    An easy-to-use and robust energy monitoring device has been developed for reliable detection of day-to-day small variations in the electron beam energy, a critical parameter for quality control and quality assurance in industrial radiation processing. It has potential for using on-line, thus providing real-time information. Its working principle is based on the measurement of currents, or charges, collected by two aluminium absorbers of specific thicknesses (dependent on the beam energy), insulated from each other and positioned within a faraday cup-style aluminium cage connected to the ground. The device has been extensively tested in the energy range of 4-12 MeV under standard laboratory conditions at Institute of Isotopes and CNR-ISOF using different types of electron accelerators; namely, a TESLA LPR-4 LINAC (3-6 MeV) and a L-band Vickers LINAC (7-12 MeV), respectively. This device has been also tested in high power electron beam radiation processing facilities, one equipped with a 7-MeV LUE-8 linear accelerator used for crosslinking of cables and medical device sterilization, and the other equipped with a 10 MeV Rhodotron TT100 recirculating accelerator used for in-house sterilization of medical devices. In the present work, we have extended the application of this method to still lower energy region, i.e. from 1.5 to 2.4 MeV. Also, we show that such a device is capable of detecting deviation in the beam energy as small as 40 keV.

  8. Turbulence measurement with a two-beam nacelle lidar

    DEFF Research Database (Denmark)

    Wagner, Rozenn; Sathe, Ameya; Mioullet, A.

    The analysis of the turbulence intensity measurement is performed for a lidar measuring horizontally with two beams. First the turbulence intensity measured by such a system was evaluated theoretically. The Mann model of turbulence was used to evaluate the true value of the turbulence intensity...... of the wind speed and the main effects of the lidar measurement principles on turbulence intensity measurement were modeled: - A lidar senses the wind speed over the probe volume acting as a low pass-filter and thus cannot resolve high frequency turbulence; - The horizontal wind speed is retrieved from...... the combination of the radial speeds measured along two line-of-sights with different orientations; this results in the contamination of the lidar turbulence intensity measurement from the transverse component of the wind field. Secondly, the theoretical results were compared to experimental measurements. A two...

  9. Beam Line Design and Beam Physics Study of Energy Recovery Linac Free Electron Laser at Peking University

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Guimei [Peking Univ., Beijing (China)

    2011-12-31

    Energy recovering linac (ERL) offers an attractive alternative for generating intense beams of charged particles by approaching the operational efficiency of a storage ring while maintaining the superior beam quality typical of a linear accelerator. In ERLs, the decelerated beam cancels the beam loading effects of the accelerated beam with high repetition rate. Therefore, ERLs can, in principle, accelerate very high average currents with only modest amounts of RF power. So the efficiency of RF power to beam is much higher. Furthermore, the energy of beam to dump is lower, so it will reduce dump radiation. With the successful experiments in large maximum-to-injection energy ratio up to 51:1 and high power FEL up to 14kW, the use of ERL, especially combining with superconducting RF technology, provides a potentially powerful new paradigm for generation of the charged particle beams used in MW FEL, synchrotron radiation sources, high-energy electron cooling devices and so on. The 3+1/2 DC-SC photo injector and two 9cell TESLA superconducting cavity for IR SASE FEL in PKU provides a good platform to achieve high average FEL with Energy Recovery. The work of this thesis is on Beam line design and Beam dynamics study of Energy Recovery Linac Free Electron Laser for Peking University. It is the upgrade of PKU facility, which is under construction. With ERL, this facility can work in CW mode, so it can operate high average beam current without RF power constraint in main linac and generate high average FEL power. Moreover, it provides a test facility to study the key technology in ERL. System parameters are optimized for PKU ERL-FEL. The oscillation FEL output power is studied with different bunch charge, transverse emittance, bunch length and energy spread. The theory of optimal RF power and Q{sub ext} with ERL and without ERL is analyzed and applied to PKU injector and linac including microphonic effect. pace charge effect in the injector and merger is studied for beam

  10. Characterization of low energy X-rays beams with an extrapolation chamber

    International Nuclear Information System (INIS)

    Bastos, Fernanda Martins

    2015-01-01

    In laboratories involving Radiological Protection practices, it is usual to use reference radiations for calibrating dosimeters and to study their response in terms of energy dependence. The International Organization for Standardization (ISO) established four series of reference X-rays beams in the ISO- 4037 standard: the L and H series, as low and high air Kerma rates, respectively, the N series of narrow spectrum and W series of wide spectrum. The X-rays beams with tube potential below 30 kV, called 'low energy beams' are, in most cases, critical as far as the determination of their parameters for characterization purpose, such as half-value layer. Extrapolation chambers are parallel plate ionization chambers that have one mobile electrode that allows variation of the air volume in its interior. These detectors are commonly used to measure the quantity Absorbed Dose, mostly in the medium surface, based on the extrapolation of the linear ionization current as a function of the distance between the electrodes. In this work, a characterization of a model 23392 PTW extrapolation chamber was done in low energy X-rays beams of the ISO- 4037 standard, by determining the polarization voltage range through the saturation curves and the value of the true null electrode spacing. In addition, the metrological reliability of the extrapolation chamber was studied with measurements of the value of leakage current and repeatability tests; limit values were established for the proper use of the chamber. The PTW23392 extrapolation chamber was calibrated in terms of air Kerma in some of the ISO radiation series of low energy; the traceability of the chamber to the National Standard Dosimeter was established. The study of energy dependency of the extrapolation chamber and the assessment of the uncertainties related to the calibration coefficient were also done; it was shown that the energy dependence was reduced to 4% when the extrapolation technique was used. Finally, the first

  11. Use of off-axis injection as an alternative to geometrically merging beams in an energy-recovering linac

    Science.gov (United States)

    Douglas, David R [York County, VA

    2012-01-10

    A method of using off-axis particle beam injection in energy-recovering linear accelerators that increases operational efficiency while eliminating the need to merge the high energy re-circulating beam with an injected low energy beam. In this arrangement, the high energy re-circulating beam and the low energy beam are manipulated such that they are within a predetermined distance from one another and then the two immerged beams are injected into the linac and propagated through the system. The configuration permits injection without geometric beam merging as well as decelerated beam extraction without the use of typical beamline elements.

  12. Measurement of neutron yield by 62 MeV proton beam on a thick Beryllium target

    International Nuclear Information System (INIS)

    Alba, R; Cosentino, G; Zoppo, A Del; Pietro, A Di; Figuera, P; Finocchiaro, P; Maiolino, C; Santonocito, D; Schillaci, M; Barbagallo, M; Colonna, N; Boccaccio, P; Esposito, J; Celentano, A; Osipenko, M; Ricco, G; Ripani, M; Viberti, C M; Kostyukov, A

    2013-01-01

    In the framework of research on IVth generation reactors and high intensity neutron sources a low-power prototype neutron amplifier was recently proposed by INFN. It is based on a low-energy, high current proton cyclotron, whose beam, impinging on a thick Beryllium converter, produces a fast neutron spectrum. The world database on the neutron yield from thick Beryllium target in the 70 MeV proton energy domain is rather scarce. The new measurement was performed at LNS, covering a wide angular range from 0 to 150 degrees and an almost complete neutron energy interval. In this contribution the preliminary data are discussed together with the proposed ADS facility.

  13. Mini biased collimated faraday cups for measurement of intense pulsed ion beams

    International Nuclear Information System (INIS)

    He Xiaoping; Shi Lei; Zhang Jiasheng; Qiu Aici

    2000-01-01

    An analysis of principle of a biased Faraday cup for measuring ion beams density and the main reasons related to the measuring accuracy were presented. An array of mini biased collimated Faraday cups was manufactured for the measurement of ion beam density of a compact 200 keV high power ion beam source. In the experiments the maximum density of ion beam was in the center of the beam, and it was about 170 A/cm 2

  14. Energy spread and time structure of ion beams extracted from the ReA-EBIT rare isotope charge breeder

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Thomas M.; Lapierre, Alain; Schwarz, Stefan; Kittimanapun, Kritsada; Bollen, Georg [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University (MSU), 640 S. Shaw Lane, East Lansing, Michigan 48824 (United States)

    2015-01-09

    The ReA re-accelerator of the National Superconducting Cyclotron Laboratory at Michigan State University utilizes an Electron Beam Ion Trap (EBIT) for charge breeding thermalized rare isotope beams. Recent commissioning measurements have been performed to characterize the performance of this EBIT. The energy spread of extracted highly charged ion beams was measured to be about 0.3% of the total beam energy. From this, the temperature of the ion ensemble in the trap is calculated to be kT{sub q}/q = 31eV for O{sup 7+}, while it is kT{sub q}/q = 25eV for K{sup 15+}. In addition initial results are presented for two extraction schemes developed to spread highly charged ion pulses in time.

  15. Beam Energy Scaling of Ion-Induced Electron Yield from K+ Ions Impact on Stainless Steel Surfaces

    CERN Document Server

    Kireeff-Covo, Michel; Barnard, John J; Bieniosek, Frank; Celata, C M; Cohen, Ronald; Friedman, Alex; Grote, D P; Kwan, Joe W; Lund, Steven M; Molvik, Arthur; Seidl, Peter; Vay, Jean-Luc; Vujic, Jasmina L; Westenskow, Glen

    2005-01-01

    The cost of accelerators for heavy-ion inertial fusion energy (HIF) can be reduced by using the smallest possible clearance between the beam and the wall from the beamline. This increases beam loss to the walls, generating ion-induced electrons that could be trapped by beam space charge potential into an "electron cloud," which can cause degradation or loss of the ion beam. In order to understand the physical mechanism of production of ion-induced electrons we have measured impact of K+ ions with energies up to 400 KeV on stainless steel surfaces near grazing incidence, using the ion source test stand (STS-500) at LLNL. The electron yield will be discussed and compared with experimental measurements from 1 MeV K+ ions in the High-Current Experiment at LBNL.*

  16. Development of time-resolved optical measurement and diagnostic system for parameters of high current and pulsed electron beam

    International Nuclear Information System (INIS)

    Jiang Xiaoguo; Wang Yuan; Yang Guojun; Xia Liansheng; Li Hong; Zhang Zhuo; Liao Shuqing; Shi Jinshui

    2013-01-01

    The beam parameters measurement is the most important work for the study of linear induction accelerator(LIA). The beam parameters are important to evaluate the character of the beam. The demands of beam parameters measurement are improving while the development of accelerator is improving. The measurement difficulty feature higher time-resolved ability, higher spatial resolution, larger dynamic range and higher intuitionistic view data. The measurement technology of beam spot, beam emittance, beam energy have been developed for the past several years. Some high performance equipment such as high speed framing camera are developed recently. Under this condition, the relative integrated optical measurement and diagnostic system for the beam parameters is developed based on several principles. The system features time-resolved ability of up to 2 ns, high sensitivity and large dynamic range. The processing program is compiled for the data process and the local real-time process is reached. The measurement and diagnostic system has provided full and accurate data for the debug work and has been put into applications. (authors)

  17. Beam loss control on the ISIS synchrotron simulations, measurements, upgrades

    CERN Document Server

    Warsop, C M

    2003-01-01

    The ISIS 800 MeV proton synchrotron presently provides 2.5*10/sup 13/ protons per pulse at 50 Hz, corresponding to a mean power of 160 kW. A dual harmonic RF system upgrade, now being installed, is expected to increase the intensity and power to about 3.75*10/sup 13/ ppp and 240 kW respectively. This paper describes work presently underway to understand and optimise beam loss control, which is a dominant factor determining operational performance. The main features of the collimation system are described, and Monte Carlo simulations of the loss control process are used to understand variations of efficiency with beam loss mode (growth rate, plane). Results of simulations are compared with measurements and operational data. Improvements to measurements are also outlined.

  18. A model to determine the initial phase space of a clinical electron beam from measured beam data.

    NARCIS (Netherlands)

    Janssen, J.J.M.; Korevaar, E.W.; Battum, L.J. van; Storchi, P.R.; Huizenga, H.

    2001-01-01

    Advanced electron beam dose calculation models for radiation oncology require as input an initial phase space (IPS) that describes a clinical electron beam. The IPS is a distribution in position, energy and direction of electrons and photons in a plane in front of the patient. A method is presented

  19. Electron-beam broadening in amorphous carbon films in low-energy scanning transmission electron microscopy.

    Science.gov (United States)

    Drees, H; Müller, E; Dries, M; Gerthsen, D

    2018-02-01

    Resolution in scanning transmission electron microscopy (STEM) is ultimately limited by the diameter of the electron beam. The electron beam diameter is not only determined by the properties of the condenser lens system but also by electron scattering in the specimen which leads to electron-beam broadening and degradation of the resolution with increasing specimen thickness. In this work we introduce a new method to measure electron-beam broadening which is based on STEM imaging with a multi-segmented STEM detector. We focus on STEM at low electron energies between 10 and 30 keV and use an amorphous carbon film with known thickness as test object. The experimental results are compared with calculated beam diameters using different analytical models and Monte-Carlo simulations. We find excellent agreement of the experimental data with the recently published model by Gauvin and Rudinsky [1] for small t/λ el (thickness to elastic mean free path) values which are considered in our study. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Determination of the energy dependence of the BC-408 plastic scintillation detector in medium energy x-ray beams

    Science.gov (United States)

    Yücel, H.; Çubukçu, Ş.; Uyar, E.; Engin, Y.

    2014-11-01

    The energy dependence of the response of BC-408 plastic scintillator (PS), an approximately water-equivalent material, has been investigated by employing standardized x-ray beams. IEC RQA and ISO N series x-ray beam qualities, in the range of 40-100 kVp, were calibrated using a PTW-type ionization chamber. The energy response of a thick BC-408 PS detector was measured using the multichannel pulse height analysis method. The response of BC-408 PS increased gradually with increasing energy in the energy range of 40-80 kVp and then showed a flat behavior at about 80 to 120 kVp. This might be due to the self-attenuation of scintillation light by the scintillator itself and may also be partly due to the ionization quenching, leading to a reduction in the intensity of the light output from the scintillator. The results indicated that the sensitivity drop in BC-408 PS material at lower photon energies may be overcome by adding some high-Z elements to its polyvinyltoluene (PVT) base. The material modification may compensate for the drop in the response at lower photon energies. Thus plastic scintillation dosimetry is potentially suitable for applications in diagnostic radiology.