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Sample records for beam extraction kicker

  1. Development of Stripline Kickers for Low Emittance Rings: Application to the Beam Extraction Kicker for CLIC Damping Rings

    CERN Document Server

    AUTHOR|(SzGeCERN)728476; Toral Fernandez, Fernando

    In the framework of the design study of Future Linear Colliders, the Compact Linear Collider (CLIC) aims for electron-positron collisions with high luminosity at a nominal centre-of-mass energy of 3 TeV. To achieve the luminosity requirements, Pre-Damping Rings (PDRs) and Damping Rings (DRs) are required: they reduce the beam emittance before the beam is accelerated in the main linac. Several injection and extraction systems are needed to inject and extract the beam from the PDRs and DRs. The work of this Thesis consists of the design, fabrication and laboratory tests of the first stripline kicker prototype for beam extraction from the CLIC DRs, although the methodology proposed can be extended to stripline kickers for any low emittance ring. The excellent field homogeneity required, as well as a good transmission of the high voltage pulse through the electrodes, has been achieved by choosing a novel electrode shape. With this new geometry, it has been possible to benefit from all the advantages that the most...

  2. Beam kicker control system for CSR project in Lanzhou

    International Nuclear Information System (INIS)

    The beam kicker system is a key part for beam extraction and injection in ring-like accelerator, which works under high voltage and huge current. This paper introduces the kicker control system based on ARM+DSP+FPGA for CSR project in Lanzhou, which has nanosecond timing precision. ARM mainly completes the control signals with the network communication, and the time control precision for the beam kicker system is performed mainly by FPGA and DSP. The sequence control signals through the optic fiber transmission, synchronous to kicker power supply the voltage to assign uses the signal isolators and ferrites to suppress the disturbance pulses. Scene test has proved that this system can meet beam kicker control's request and work safely and stably. The control system has extracted and injected the CSR beam successfully in October 2007. (authors)

  3. Wideband Precision Current Transformer for the Magnet Current of the Beam Extraction Kicker Magnet of the Large Hadron Collider

    CERN Document Server

    Gräwer, G

    2004-01-01

    The LHC beam extraction system is composed of 15 fast kicker magnets per beam to extract the particles in one turn of the collider and to safely dispose them on external absorbers. Each magnet is powered by a separate pulse generator. The generator produces a magnet current pulse with 3 us rise time, 20 kA amplitude and 1.8 ms fall time, of which 90 us are needed to dump the beam. The beam extraction system requires a high level of reliability. To detect any change in the magnet current characteristics, which might indicate a slow degradation of the pulse generator, a high precision wideband current transformer will be installed. For redundancy reasons, the results obtained with this device will be cross-checked with a Rogowski coil, installed adjacent to the transformer. A prototype transformer has been successfully tested at nominal current levels and showed satisfactory results compared with the output of a high frequency resistive coaxial shunt. The annular core of the ring type transformer is composed of...

  4. Spiral kicker for the beam abort system

    Energy Technology Data Exchange (ETDEWEB)

    Martin, R.L.

    1983-01-01

    A brief study was carried out to determine the feasibility of a special kicker to produce a damped spiral beam at the beam dump for the beam abort system. There appears to be no problem with realizing this concept at a reasonably low cost.

  5. Dilution kicker for the SPS beam dump

    CERN Multimedia

    1974-01-01

    In order to reduce thermal stress on the SPS dump material, the fast-ejected beam was swept horizontally across the dump. This was done with the "dilution kicker" MKDH, still in use at the time of writing. The person on the left is Manfred Mayer. See also 7404072X.

  6. Dilution kicker for the SPS beam dump

    CERN Multimedia

    1974-01-01

    In order to reduce thermal stress on the SPS dump material, the fast-ejected beam was swept horizontally across the dump. This was done with the "dilution kicker" MKDH, still in use at the time of writing. See also 7402051X.

  7. The SPS Fast Extraction Kicker System in LSS6

    CERN Document Server

    Gaxiola, E; Ducimetière, L; Faure, P; Kroyer, T; Versolatto, B; Vossenberg, G

    2006-01-01

    A new fast extraction has been set up in SPS LSS6 to transfer 450 GeV/c protons as well as ions to Ring 1 of the LHC, via the transfer line TI 2. The system includes four travelling wave kicker magnets, all powered in series, energised by a single PFN generator and terminated by a short circuit. The layout and the modifications to the magnets and the high voltage circuit are described along with the impact of design choices on the performance of the system. Results from laboratory tests are reported on approaches to overcome the effects of the beam induced kicker heating observed earlier, including a beam screen in form of metallic stripes printed directly onto the ferrites and the use of high Curie temperature ferrites. Prospects for further improvements are briefly discussed.

  8. Construction and Power Test of the Extraction Kicker Magnet for the Spallation Neutron Source Accumulator Ring

    CERN Document Server

    Pai, Chien; Hseuh Hsiao Chaun; Meng, Wuzheng; Mi, Jian-Lin; Raparia, Deepak; Sandberg, Jon; Todd, Robert J; Tsoupas, Nicholaos; Tuozzolo, Joseph; Warburton, David S; Wei, Jie; Weiss, Daniel; Yung Lee, Yong; Zhang, Wu

    2005-01-01

    Two extraction kicker magnet assemblies that contain seven individual pulsed magnet modules each will kick the proton beam vertically out of the SNS accumulator ring into the aperture of the extraction lambertson septum magnet. The proton beam then travels to the 1.4 MW SNS target assembly. The 14 kicker magnets and major components of the kicker assembly have been fabricated in BNL. The inner surfaces of the kicker magnets were coated with TiN to reduce the secondary electron yield. All 14 PFN power supplies have been built, tested and delivered to ORNL. Before final installation, a partial assembly of the kicker system with three kicker magnets was assembled to test the functions of each critical component in the system. In this paper we report the progress of the construction of the kicker components, the TiN coating of the magnets, the installation procedure of the magnets and the full power test of the kicker with the PFN power supply.

  9. Los Alamos Proton Storage Ring fast-extraction kicker system

    International Nuclear Information System (INIS)

    We describe the kicker system used by the Los Alamos Proton Storage Ring (PSR) for fast extraction of accumulated 800-MeV proton beam. The system has several severe constraints in terms of rise time, field quality, and magnet dimensions. These are, in turn, defined by characteristics of the stored beam, ring lattice, and the allowable activation of ring components. Design methods to meet the constraints are outlined here and we describe the novel modulators that produce the fast pulses required. 3 refs., 7 figs

  10. Beam transport experiment with a new kicker control system on the HIRFL-CSR

    CERN Document Server

    Wang, Yan-Yu; Luo, Jin-Fu; Zhang, Jian-Chuan; Zhou, Wen-Xiong; Ni, Fa-Fu; Yin, Jun; Yin, Jia; Yuan, You-Jin; Shang-Guan, Jin-Bin

    2015-01-01

    The kicker control system was used for beam extraction and injection between two cooling storage rings (CSRs) at the Heavy Ion Research Facility in Lanzhou (HIRFL). To meet the requirements of special physics experiments, the kicker controller was upgraded. The new controller was designed based on ARM+DSP+FPGA technology and monolithic circuit architecture, which can achieve a precision time delay of 2.5 ns. In September 2014, the new kicker control system was installed in the kicker field, and the test experiment using the system was completed. In addition, a pre-trigger signal was provided by the controller, which was designed to synchronize the beam diagnostic system and physics experiments. Experimental results indicate that the phenomena of "missed kick" and "inefficient kick" were not observed, and the multichannel trigger signals' delay could be adjusted individually for kick power supplies in digitization; thus, the beam transport efficiency was improved compared with that of the original system. The ...

  11. Beam transport experiment with a new kicker control system on the HIRFL

    Science.gov (United States)

    Yan-Yu, Wang; De-Tai, Zhou; Jin-Fu, Luo; Jian-Chuan, Zhang; Wen-Xiong, Zhou; Fa-Fu, Ni; Jun, Yin; Jia, Yin; You-Jin, Yuan; Jing-Bin, Shang-Guan

    2016-04-01

    A kicker control system is used for beam extraction and injection between two cooling storage rings (CSRs) at the Heavy Ion Research Facility in Lanzhou (HIRFL). To meet the requirements of special physics experiments, the kicker controller has been upgraded, with a new controller designed based on ARM+DSP+FPGA technology and monolithic circuit architecture, which can achieve a precision time delay of 2.5 ns. In September 2014, the new kicker control system was installed in the kicker field, and the test experiment using the system was completed. In addition, a pre-trigger signal was provided by the controller, which was designed to synchronize the beam diagnostic system and physics experiments. Experimental results indicate that the phenomena of “missed kick” and “inefficient kick” were not observed, and the multichannel trigger signal delay could be adjusted individually for kick power supplies in digitization; thus, the beam transport efficiency was improved compared with that of the original system. The fast extraction and injection experiment was successfully completed based on the new kicker control systems for HIRFL. Supported by National Natural Science Foundation of China (U1232123)

  12. Physical and Electromagnetic Properties of Customized Coatings for SNS Injection Ceramic Chambers and Extraction Ferrite Kickers

    CERN Document Server

    Hseuh Hsiao Chaun; He, Ping; Henderson, Stuart; Pai, Chien; Raparia, Deepak; Todd, Robert J; Wang, Lanfa; Wei, Jie; Weiss, Daniel; Yung Lee, Yong

    2005-01-01

    The inner surfaces of the 248 m SNS accumulator ring vacuum chambers are coated with ~100 nm of titanium nitride (TiN) to reduce the secondary electron yield (SEY) of the chamber walls. All the ring inner surfaces are made of stainless or inconel, except those of the injection and extraction kickers. Ceramic vacuum chambers are used for the 8 injection kickers to avoid shielding of a fast-changing kicker field and to reduce eddy current heating. The internal diameter was coated with Cu to reduce the beam coupling impedance and provide passage for beam image current, and a TiN overlayer to reduce SEY. The ferrite surfaces of the 14 extraction kicker modules were coated with TiN to reduce SEY. Customized masks were used to produce coating strips of 1 cm x 5 cm with 1 to 1.5 mm separation among the strips. The masks maximized the coated area to more than 80%, while minimizing the eddy current effect to the kicker rise time. The coating method, as well as the physical and electromagnetic properties of the coating...

  13. Literature file on 'fast kickers and septa', componenets for deflection and separation of particle beams

    International Nuclear Information System (INIS)

    The File consists of classified and numbered articles from the literature on the following subjects: 1 - Kickers: fast switching (electro-)magnetic or electrostatic components for small deflection; 2 - Septum Magnets: both small and great deflecting components, with the purpose to create or bridge over space between the deflected beam and the other, unperturbed beam; 3 - Electrostatic Septa: low loss, beam splitting components which give small deflection for the extracted part of the beam and no perturbation for the rest of the beam. The articles have been classified per institute or laboratory, eventually with further classification per project. The classified articles are then numbered chronologically. Extension of the File is still possible. The contents of the articles are summarized by means of catchwords. Specifications of the described kickers, septum magnets and electrostatic septa are represented in a tabular form

  14. Upgrading the Fast Extractions Kicker System in SPS LSS6

    CERN Document Server

    Barnes, M; Goddard, B; Uythoven, J

    2008-01-01

    A fast extraction system, located in the LSS6 region of the CERN SPS accelerator, transfers 450 GeV/c protons, as well as ions, via the TI 2 transfer line towards the LHC. The system includes three travelling wave kicker magnets, all powered in series, energised by a single Pulse Forming Network (PFN) and terminated by a short circuit. The specification for the system requires a kick flattop of $7.8 \\mu$s with a ripple of not more than ±0.5%. Recent measurements with beam show that the ±0.5% kick specification is achieved over $7.1 \\mu$s of the kick flattop; however the ripple over $7.8 \\mu$s is ±0.75%. Initial electrical measurements have been carried out on each of the three magnets; more detailed comparisons of the beam measurements and the contribution of each magnet to the detailed shape of the flattop kick will be carried out. This paper reports the results of initial measurements and plans for future measurements to permit modifications to the PFN for reducing flattop ripple.

  15. Development of 50 kV ultra-fast dipole-quadrupole kicker for bucket-by-bucket beam handling

    International Nuclear Information System (INIS)

    Ultra-fast dipole / quadrupole field variable kicker was developed for bucket-by-bucket handling of a beam and tested with a 1 GeV electron beam from the SPring-8 linac. The kicker produces dipole field to quadrupole field by changing the driving voltage and polarity. The kicker was tested with 50 kV pulse generator and the high kick field was expected in the kicker. For dipole kick, the kicker does not impose the horizontal aperture. (author)

  16. GAS DISCHARGE SWITCH EVALUATION FOR RHIC BEAM ABORT KICKER APPLICATION

    International Nuclear Information System (INIS)

    A gas discharge switch EEV HX3002 is being evaluated at Brookhaven National Laboratory as a possible candidate of RHIC Beam Abort Kicker modulator main switch. At higher beam energy and higher beam intensity, the switch stability becomes very crucial. The hollow anode thyratron used in the existing system is not rated for long reverse current conduction. The reverse voltage arcing caused thyratron hold-off voltage de-rating has been the main limitation of the system operation. To improve the system reliability, a new type of gas discharge switch has been suggested by Marconi Applied Technology for its reverse conducting capability

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

    International Nuclear Information System (INIS)

    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

  18. The Low-Level Control System for the CERN PS Multi-Turn Extraction Kickers

    CERN Document Server

    Schipper, J; Boucly, C; Carlier, E; Fowler, T; Gaudillet, H; Noulibos, R; Sermeus, L

    2010-01-01

    To reduce the beam losses when preparing high intensity proton beam for the CERN Neutrino to Gran Sasso (CNGS) facility, a new Multi-Turn extraction (MTE) scheme has been implemented in the PS, to replace the present Continuous Transfer (CT) to the SPS. Industrial off-the-shelf components have been used for the low-level part of the MTE kicker control system. National Instruments PXI systems are used to control the high voltage pulse generators and a SIEMENS programmable logic controller (PLC) handles the centralised oil cooling and gas insulation sub-systems

  19. Transient beam losses in the LHC injection kickers from micron scale dust particles

    CERN Document Server

    Goddard, B; Baer, T; Barnes, M J; Cerutti, F; Ferrari, A; Garrel, N; Gerardin, A; Guinchard, M; Lechner, A; Masi, A; Mertens, V; Morón Ballester, R; Redaelli, S; Uythoven, J; Vlachoudis, V; Zimmermann, F

    2012-01-01

    Transient beam losses on a time scale of a few ms have been observed in the LHC injection kickers, occurring mainly shortly after beam injection with a strong correlation in time to the kicker pulsing. The beam losses, which have at times affected LHC availability, are attributed to micron scale ceramic dust particles detached from the alumina beam pipe and accelerated into the beam. The beam related observations are described, together with laboratory measurements of beam pipe contamination and kicker vibration, simulations of electric field in the beam pipe and the basic dynamic model. Energy deposition simulations modelling the beam losses are presented and compared to measurement. Extrapolations to future LHC operation at higher intensities and energies are made, and prospects for mitigation are discussed.

  20. In situ baking method for degassing of a kicker magnet in accelerator beam line

    Energy Technology Data Exchange (ETDEWEB)

    Kamiya, Junichiro, E-mail: kamiya.junichiro@jaea.go.jp; Ogiwara, Norio; Yanagibashi, Toru; Kinsho, Michikazu [Japan Atomic Energy Agency, J-PARC Center, Ooaza Shirakata 2-4, Tokai, Naka, Ibaraki 319-1195 (Japan); Yasuda, Yuichi [SAKAGUCHI E.H VOC CORP., Sakura Dai-san Kogyodanchi 1-8-6, Osaku, Sakura, Chiba 285-0802 (Japan)

    2016-03-15

    In this study, the authors propose a new in situ degassing method by which only kicker magnets in the accelerator beam line are baked out without raising the temperature of the vacuum chamber to prevent unwanted thermal expansion of the chamber. By simply installing the heater and thermal radiation shield plates between the kicker magnet and the chamber wall, most of the heat flux from the heater directs toward the kicker magnet. The result of the verification test showed that each part of the kicker magnet was heated to above the target temperature with a small rise in the vacuum chamber temperature. A graphite heater was selected in this application to bake-out the kicker magnet in the beam line to ensure reliability and easy maintainability of the heater. The vacuum characteristics of graphite were suitable for heater operation in the beam line. A preliminary heat-up test conducted in the accelerator beam line also showed that each part of the kicker magnet was successfully heated and that thermal expansion of the chamber was negligibly small.

  1. Beam Coupling Impedance of the New Beam Screen of the LHC Injection Kicker Magnets

    CERN Document Server

    Day, H; Caspers, F; Métral, E; Salvant, B; Uythoven, J

    2014-01-01

    The LHC injection kicker magnets experienced significant beam induced heating of the ferrite yoke, with high beam currents circulating for many hours, during operation of the LHC in 2011 and 2012. The causes of this beam induced heating were studied in depth and an improved beam screen implemented to reduce the impedance. Results of measurements and simulations of the new beam screen design are presented in this paper: these are used to predict power loss for operation after long shutdown 1 and for proposed HL-LHC operational parameters.

  2. RF-Kicker System for Secondary Beams at NSCL/MSU

    CERN Document Server

    Gorelov, Dmitry; Bazin, Daniel; Doleans, Marc; Grimm, Terry L; Marti, Felix; Vincent, John; Wu, Xiaoyu

    2005-01-01

    The design and construction of a radio frequency (RF) kicker system at the National Superconducting Cyclotron Laboratory (NSCL), Michigan State University (MSU) has been proposed. This RF kicker system will be used to purify secondary beams of rare isotopes after the existing A1900 Fragment Separator and will open a wide range of possibilities for new experiments at the forefront of nuclear science. The proposed system is studied as an efficient alternative to the traditional approach using Wien Filter. Rare neutron deficient secondary beams are challenging to purify because of the presence of intense contaminants that cannot be removed by the traditional energy loss method. However, velocity differences resulting in time-of-flight differences can be used for the effective separation of the beams transversely using the time-varying electromagnetic fields of the RF kicker. Its technical design will be presented together with the beam dynamics analysis of a secondary beam in realistic 3D electromagnetic fields....

  3. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than \\pm0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within \\pm0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  4. Present status of development of damping ring extraction kicker system for CLIC

    CERN Document Server

    Holma, Janne; Belver-Aguilar, Caroline; Faus-Golfe, Angeles; Toral, Fernando

    2012-01-01

    The CLIC damping rings will produce ultra-low emittance beam, with high bunch charge, necessary for the luminosity performance of the collider. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the damping ring kickers must provide extremely flat, high-voltage pulses: specifications call for a 160 ns duration and a flattop of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. The stripline design is also extremely challenging: the field for the damping ring kicker system must be homogenous to within ±0.01 % over a 1 mm radius, and low beam coupling impedance is required. The solid-state modulator, the inductive adder, is a very promising approach to meeting the demanding specifications for the field pulse ripple and droop. This paper describes the initial design of the inductive adder and the striplines of the kicker system.

  5. Particle kickers

    CERN Multimedia

    Antonella Del Rosso

    2014-01-01

    These devices are designed to provide a current pulse of 5000 Amps which will in turn generate a fast magnetic pulse that steers the incoming beam into the LHC. Today, the comprehensive upgrade of the LHC injection kicker system is entering its final stages. The upgraded system will ensure the LHC can be refilled without needing to wait for the kicker magnets to cool, thus enhancing the performance of the whole accelerator.   An upgraded kicker magnet in its vacuum tank, with an upgraded beam screen. The LHC is equipped with two kicker systems installed at the injection points (near points 2 and 8, see schematic diagram) where the particle beams coming from the SPS are injected into the accelerator’s orbit. Each system comprises four magnets and four pulse generators in which the field rises to 0.12 Tesla in less than 900 nanoseconds and for a duration of approximately 8 microseconds. Although the injection kickers only pulse 12 times to fill the LHC up with beam, the LHC beam circ...

  6. Physical and Structural Design of Fast Extraction Kickers for CSNS/RCS

    CERN Document Server

    Lei, Wang; Yao-Dou, Hao; Yuan, Chen; Li-Hua, Huo

    2013-01-01

    China Spallation Neutron Source (CSNS) is a high intensity beam facility being built now in China. Three kicker assemblies, eight pulsed magnets, will be used in the CSNS rapid circle synchrotron (RCS). The physical and structural designs of eight kicker magnets that are grouped in 5 different types are presented. The results of OPERA-3D simulation show that magnet center field integral meet the physics requirements of design by choosing a suitable magnet coil structure. Field uniformity for 60% width is +/-0.7%. The ferrite magnet structure and composition is introduced, and the high voltage feedthrough design, the installation of six magnets in long vacuum cavity design is discussed.

  7. Transient Thermal Analysis of Intense Proton Beam Loss on a Kicker Magnet Conductor Plate

    CERN Document Server

    Knaus, P

    2000-01-01

    The Super Proton Synchrotron SPS will be used as injector for the Large Hadron Collider LHC and needs adaptation to meet LHC requirements. The SPS injection kicker magnets MKP will undergo important modifications to comply with the requirements on magnetic field rise-time and ripple. The injection kicker presently installed has a return conductor of beryllium to minimise the risk of metal evaporation from its surface due to heating caused by beam impact. In the context of refurbishing the MKP to satisfy LHC requirements these conductors need replacement, preferably with a less delicate material. This article presents the transient thermal analysis of energy deposition caused by beam loss on the conductor plate. The expected time structure of the beam is taken into account. Simulations comparing different conductor materials have been performed, leading to the result that a significantly cheaper and fully inoffensive titanium alloy can satisfy the needs.

  8. Beam-Based Measurement of the Waveform of the LHC Injection Kickers

    CERN Document Server

    Barnes, M J; Goddard, B; Hessler, C; Mertens, V; Uythoven, J

    2010-01-01

    Proton and ion beams are injected into LHC at 450 GeV by two kicker magnet systems, producing magnetic field pulses of up to 7.8 ms flat top duration with rise and fall times of not more than 900 ns and 3 ms, respectively. Both systems are composed of four travelling wave kicker magnets, powered by pulse forming networks. One of the stringent design requirements of these systems is a field flat top and postpulse ripple of less than ±0.5 %. A carefully matched high bandwidth system is required to obtain the required pulse response. Screen conductors are placed in the aperture of the kicker magnet to provide a path for the image current of the, high intensity, LHC beam and screen the ferrite against wake fields. However, these conductors affect the field pulse response. Recent injection tests provided the opportunity to directly measure the shape of the kick field pulse, with high accuracy, using a pilot beam. This paper details the measurements and compares the results with predictions and laboratory measurem...

  9. The fast extraction kicker power supply for the main ring of J-PARC

    International Nuclear Information System (INIS)

    An effect induced by parasitic inductance in a pulsed power supply for a fast extraction kicker was studied. The parasitic inductance in high voltage capacitors for a low impedance pulse forming network disturbs a sharp rise of an excitation current. A high voltage capacitor with a coaxial structure to minimize the parasitic inductance is proposed. The effectiveness was confirmed experimentally. An impedance mismatch by a leakage inductance of a pulse transformer in a transmission line was studied. The effect is serious at the flat-top period of the excitation current. By introducing a compensation circuit, which is composed by a capacitor and a resistor, impedance matching was established. The pulsed power supply for the fast extraction kicker was operated at a charging voltage of 30 kV. A required rise time of less than 1.1 μs was achieved. The flatness was also confirmed to be in an acceptable value of less than 1%. -- Highlights: ●An effect by parasitic inductance of the energy storage capacitor of the PFN was studied. ●A faster rise time was achieved by introducing a coaxial structure for the PFN capacitor. ●An impedance mismatch by a leakage inductance of a pulse transformer was studied. ●Serious deterioration of the pulsed waveform was cured by a compensation circuit. ●The pulsed power supply for the fast extraction kicker was developed and operated successfully

  10. Impedance measurements of the extraction kicker system for the rapid cycling synchrotron of China Spallation Neutron Source

    Science.gov (United States)

    Liang-Sheng, Huang; Sheng, Wang; Yu-Dong, Liu; Yong, Li; Ren-Hong, Liu; Ou-Zheng, Xiao

    2016-04-01

    The fast extraction kicker system is one of the most important accelerator components and the main source of impedance in the Rapid Cycling Synchrotron of the China Spallation Neutron Source. It is necessary to understand the kicker impedance before its installation into the tunnel. Conventional and improved wire methods are employed in the impedance measurement. The experimental results for the kicker impedance are explained by comparison with simulation using CST PARTICLE STUDIO. The simulation and measurement results confirm that the window-frame ferrite geometry and the end plate are the important structures causing coupling impedance. It is proved in the measurements that the mismatching from the power form network to the kicker leads to a serious oscillation sideband of the longitudinal and vertical impedance and the oscillation can be reduced by ferrite absorbing material. Supported by National Natural Science Foundation of China (11175193, 11275221)

  11. Advances of Transmission line kicker magnets

    CERN Document Server

    Ducimetière, Laurent

    2005-01-01

    Fast pulsed magnets or kickers are widely used in circular accelerators for injection, fast extraction and beam excitation. As from the early 60’s transmission line type kicker magnets have been employed to produce rectangular field pulses with good rise time. Over some 40 years this technology has evolved with the rising requirements. While the necessary kick strength has increased with the particle beam energy the strive for efficiency has pushed developments towards lower impedance systems and/or short circuited magnets. The flat top ripple is constrained by the maximally tolerable beam oscillation. The beam intensity can impose a screening of the magnet yoke. The most advanced features implemented in recent transmission line kicker magnets are reviewed and illustrated with examples from different laboratories.

  12. Development of a Fast High-Power Pulser and ILC DR Injection/Extraction Kicker

    Energy Technology Data Exchange (ETDEWEB)

    Krasnykh, A.; /SLAC

    2007-10-16

    Kicker is an efficient HOM power extractor. Peak HOM voltage and average power at the feeder may be sufficient to act on the kicker pulser. Feeder imperfections (real cable, feedthroughs, kicker electrodes, loads) is one source of residual energy between bunches. HOM spectrum is broad.

  13. SPS Injection and Beam Quality for LHC Heavy Ions With 150 ns Kicker Rise Time

    CERN Document Server

    Goddard, Brennan; Ducimetière, Laurent; Kotzian, Gerd; Uythoven, Jan; Velotti, Francesco

    2016-01-01

    As part of the LHC Injectors Upgrade project for LHC heavy ions, the SPS injection kicker system rise time needs reduction below its present 225 ns. One technically challenging option under consideration is the addition of fast Pulse Forming Lines in parallel to the existing Pulse Forming Networks for the 12 kicker magnets MKP-S, targeting a system field rise time of 100 ns. An alternative option is to optimise the system to approach the existing individual magnet field rise time (2-98%) of 150 ns. This would still significantly increase the number of colliding bunches in LHC while minimising the cost and effort of the system upgrade. The observed characteristics of the present system are described, compared to the expected system rise time, together with results of simulations and measurements with 175 and 150 ns injection batch spacing. The expected beam quality at injection into LHC is quantified, with the emittance growth and simulated tail population taking into account expected jitter and synchronisatio...

  14. Development of the kicker magnet for muses

    International Nuclear Information System (INIS)

    In the MUSES project, kicker magnets are used for the fast extraction of ion-beams. The extraction kicker field is required to rise from approximately 10% to 99% of the full strength of 0.084 T during the time interval between bunches. The high performance of the kicker magnet is important for the efficiency of beam extraction. Based on the traveling-wave-type kicker magnet, we have succeeded in shortening field rise-time and improving the field uniformity. We have measured the magnetic field variation and distribution with a long and short search coils. To measure the field variation accurately, we have used newly devised coaxial-type attenuators instead of a conventional high-voltage probe. In order to improve the signal-to-noise ratio, two signals measured by switching the polarity of the search coil are averaged upon changing the sign. The rise-time of the waveform is approximately 83 ns, and the flat-top time is 888 ns. The uniformity of the magnetic field along the horizontal axis is better than ±0.2% in the range of 85 mm. We have developed a kicker magnet mostly satisfying our requirements for the MUSES project

  15. An IGBT Driven Slotted Beam Pipe Kicker for SPEAR III Injection

    International Nuclear Information System (INIS)

    The SPEAR III injection kicker system is composed of three kicker magnets, K1, K2, and K3. These magnets, along with the power modulators to drive them constitute an injection system which will be used to deflect an incoming electron beam with an energy of 3.3 GeV by an angle of 2.5 mrad for K1 and K3, and 1 mrad for K2. The pulse shape of the magnetic field in the three magnets must be matched in order to preserve a closed orbit. The pulse duration is required to be less than 780 ns, with rise and fall times of less than 375 ns, and a pulse repetition frequency of 10 Hz. The aperture of all three magnets is 60 x 34 mm in an 8 inch vacuum vessel. The magnetic length is 1.2 m for K1 and K3, and 0.6 m for K2 [1]. The magnet design employs a slotted beam pipe which is shorted at one end. A solid state IGBT based, induction type of modulator drives the magnets. Modulators for K1 and K3 consist of eight 4.5 kV, 600 A IGBTs, and eight Finemet magnet cores with four 22.5 Ohm output cables to drive 2381 A into the magnets. The modulator for K2 uses four IGBTs and cores, and 8 output cables to produce a 2619 A pulse. Cables of length greater than one half the pulse width must be used in order to avoid reflections from the shorted magnet. The design charge voltage for the modulators is 20 kV for K1 and K3. This paper describes the magnet and modulator design, as and presents test data from a prototype system

  16. Emittance Growth at LHC Injection from SPS and LHC Kicker Ripple

    CERN Document Server

    Kotzian, G; Ducimetière, L; Goddard, B; Höfle, Wolfgang

    2008-01-01

    Fast pulsed kicker magnets are used to extract beams from the SPS and inject them into the LHC. The kickers exhibit time-varying structure in the pulse shape which translates into small offsets with respect to the closed orbit at LHC injection. The LHC damper systems will be used to damp out the resulting betatron oscillations, to keep the growth in the transverse emittance within specification. This paper describes the results of the measurements of the kicker ripple for the two systems, both in the laboratory and with beam, and presents the simulated performance of the transverse damper in terms of beam emittance growth. The implications for LHC operation are discussed.

  17. High field, high repetition rate kicker

    CERN Document Server

    Ishi, Y; Muto, M; Shirakabe, Y; Takagi, A

    2001-01-01

    New kicker magnet systems and their related technologies are being developed and tested at KEK. The kickers are to be used both for the injection and for the fast extraction of two rings, the 50 GeV proton synchrotron in the 'Joint Project' of JAERI-KEK and the PRISM/FFAG ring for the muon beam. In order to obtain a sufficient kick on the high-intensity beam in the 50 GeV proton ring, the kicker systems must have both large apertures and high fields. In addition to this, the PRISM/FFAG ring demands muon beams with a high repetition rate of injection and extraction. The requested repetition rate is 1 kHz or higher. In order to fulfill those demands, new technologies have been introduced and are now being tested. Among them are high-power IGBT modules, a subordinated-gating system, 1 kHz repetition pulsed power supply, and kickers with magnetic-alloy cores used as return yokes.

  18. A gap clearing kicker for Main Injector

    CERN Document Server

    Kourbanis, I; Biggs, J; Brown, B; Capista, D; Jensen, C C; Krafczyk, G E; Morris, D K; Scott, D; Seiya, K; Ward, S R; Wu, G; Yang, M -J

    2012-01-01

    Fermilab Main Injector has been operating at high Beam Power levels since 2008 when multi-batch slip stacking became operational. In order to maintain and increase the beam power levels the localized beam loss due to beam left over in the injection kicker gap during slip stacking needs to be addressed. A set of gap clearing kickers that kick any beam left in the injection gap to the beam abort have been built. The kickers were installed in the summer of 2009 and became operational in November of 2010. The kicker performance and its effect on the beam losses will be described.

  19. MI Gap Clearing Kicker Magnet Design Review

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Chris; /Fermilab

    2008-10-01

    The kicker system requirements were originally conceived for the NOvA project. NOvA is a neutrino experiment located in Minnesota. To achieve the desired neutrino flux several upgrades are required to the accelerator complex. The Recycler will be used as a proton pre-injector for the Main Injector (MI). As the Recycler is the same size as the MI, it is possible to do a single turn fill ({approx}11 {micro}sec), minimizing the proton injection time in the MI cycle and maximizing the protons on target. The Recycler can then be filled with beam while the MI is ramping to extract beam to the target. To do this requires two new transfer lines. The existing Recycler injection line was designed for 10{pi} pbar beams, not the 20{pi} proton beams we anticipate from the Booster. The existing Recycler extraction line allows for proton injection through the MI, while we want direct injection from the Booster. These two lines will be decommissioned. The new injection line from the MI8 line into the Recycler will start at 848 and end with injection kickers at RR104. The new extraction line in the RR30 straight section will start with a new extraction kicker at RR232 and end with new MI injection kickers at MI308. Finally, to reduce beam loss activation in the enclosure, a new gap clearing kicker will be used to extract uncaptured beam created during the slip stack injection process down the existing dump line. It was suggested that the MI could benefit from this type of system immediately. This led to the early installation of the gap clearing system in the MI, followed by moving the system to Recycler during NOvA. The specifications also changed during this process. Initially the rise and fall time requirements were 38 ns and the field stability was {+-}1%. The 38 ns is based on having a gap of 2 RF buckets between injections. (There are 84 RF buckets that can be filled from the Booster for each injection, but 82 would be filled with beam. MI and Recycler contain 588 RF buckets

  20. Feasibility Study of the PS Injection for 2 GeV LIU Beams with an Upgraded KFA-45 Injection Kicker System Operating in Short Circuit Mode

    CERN Document Server

    Kramer, Thomas; Borburgh, Jan; Ducimetière, Laurent; Feliciano, Luis; Ferrero Colomo, Alvaro; Goddard, Brennan; Sermeus, Luc

    2016-01-01

    Under the scope of the LIU project the CERN PS Booster to PS beam transfer will be modified to match the requirements for the future 2 GeV beams. This paper describes the evaluation of the proposed upgrade of the PS injection kicker. Different schemes of an injection for LIU beams into the PS have been outlined in the past already under the aspect of individual transfer kicker rise and fall time performances. Homogeneous rise and fall time requirements in the whole PSB to PS transfer chain have been established which allowed to consider an upgrade option of the present injection kicker system operated in short circuit mode. The challenging pulse quality constraints require an improvement of the flat top and post pulse ripples. Both operation modes, terminated and short circuit mode are analysed and analogue circuit simulations for the present and upgraded system are outlined. Recent measurements on the installed kickers are presented and analysed together with the simulation data. First measurements verifying...

  1. DESIGN CONSIDERATIONS OF FAST KICKER SYSTEMS FOR HIGH INTENSITY PROTON ACCELERATORS

    International Nuclear Information System (INIS)

    In this paper, we discuss the specific issues related to the design of the Fast Kicker Systems for high intensity proton accelerators. To address these issues in the preliminary design stage can be critical since the fast kicker systems affect the machine lattice structure and overall design parameters. Main topics include system architecture, design strategy, beam current coupling, grounding, end user cost vs. system cost, reliability, redundancy and flexibility. Operating experience with the Alternating Gradient Synchrotron injection and extraction kicker systems at Brookhaven National Laboratory and their future upgrade is presented. Additionally, new conceptual designs of the extraction kicker for the Spallation Neutron Source at Oak Ridge and the Advanced Hydrotest Facility at Los Alamos are discussed

  2. Upgrade of a kicker control system for the HIRFL

    International Nuclear Information System (INIS)

    A kicker system plays an important role in beam extraction and injection for a ring-like accelerator. The kicker system in the Heavy Ion Research Facility in Lanzhou (HIRFL) is used for beam extraction and injection between two cooling storage rings (CSRs). The system consists of two parts: one part is used for beam extraction from the CSR/main (CSRm), and the other is used for beam injection into the CSR/experimental (CSRe). To meet the requirements of special physics experiments, we upgraded the kicker control system. In this upgraded system, the position of the beam bunches can be determined by measuring the phase of the radio frequency (RF) signal in real time because each beam bunch is synchronized with the RF signal. The digital timing control and delay regulatory function, which are based on a new design using ARM+DSP+FPGA technology, achieved a precision of 2.5 ns, which is a significant improvement over old system's precision of 5 ns. In addition, this system exhibits a better anti-interference capability. Moreover, the efficiency of beam extraction can be enhanced, and the accuracy of the reference voltage setting can reach as low as 0.1%, compared to 2% for the old system

  3. Upgrade of a kicker control system for the HIRFL

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yan-Yu, E-mail: yanyu@impcas.ac.cn [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhou, Wen-Xiong; Luo, Jin-Fu [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of the Chinese Academy of Sciences, Beijing 100039 (China); Zhou, De-Tai [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhang, Jian-Chuan [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); University of the Chinese Academy of Sciences, Beijing 100039 (China); Ma, Xiao-Li; Gao, Da-Qing; Shang-Guan, Jing-Bin [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2014-02-21

    A kicker system plays an important role in beam extraction and injection for a ring-like accelerator. The kicker system in the Heavy Ion Research Facility in Lanzhou (HIRFL) is used for beam extraction and injection between two cooling storage rings (CSRs). The system consists of two parts: one part is used for beam extraction from the CSR/main (CSRm), and the other is used for beam injection into the CSR/experimental (CSRe). To meet the requirements of special physics experiments, we upgraded the kicker control system. In this upgraded system, the position of the beam bunches can be determined by measuring the phase of the radio frequency (RF) signal in real time because each beam bunch is synchronized with the RF signal. The digital timing control and delay regulatory function, which are based on a new design using ARM+DSP+FPGA technology, achieved a precision of 2.5 ns, which is a significant improvement over old system's precision of 5 ns. In addition, this system exhibits a better anti-interference capability. Moreover, the efficiency of beam extraction can be enhanced, and the accuracy of the reference voltage setting can reach as low as 0.1%, compared to 2% for the old system.

  4. Upgrade of a kicker control system for the HIRFL

    Science.gov (United States)

    Wang, Yan-Yu; Zhou, Wen-Xiong; Luo, Jin-Fu; Zhou, De-Tai; Zhang, Jian-Chuan; Ma, Xiao-Li; Gao, Da-Qing; Shang-Guan, Jing-Bin

    2014-02-01

    A kicker system plays an important role in beam extraction and injection for a ring-like accelerator. The kicker system in the Heavy Ion Research Facility in Lanzhou (HIRFL) is used for beam extraction and injection between two cooling storage rings (CSRs). The system consists of two parts: one part is used for beam extraction from the CSR/main (CSRm), and the other is used for beam injection into the CSR/experimental (CSRe). To meet the requirements of special physics experiments, we upgraded the kicker control system. In this upgraded system, the position of the beam bunches can be determined by measuring the phase of the radio frequency (RF) signal in real time because each beam bunch is synchronized with the RF signal. The digital timing control and delay regulatory function, which are based on a new design using ARM+DSP+FPGA technology, achieved a precision of 2.5 ns, which is a significant improvement over old system's precision of 5 ns. In addition, this system exhibits a better anti-interference capability. Moreover, the efficiency of beam extraction can be enhanced, and the accuracy of the reference voltage setting can reach as low as 0.1%, compared to 2% for the old system.

  5. The RHIC injection kicker

    International Nuclear Information System (INIS)

    Beam transfer from the AGS to RHIC is performed in single-bunch mode. Close spacing of the bunches in the collider requires an injection kicker with a rise time of <90 nsec, suggesting adoption of a travelling wave structure. The required vertical kick of 0.186 t·m is provided by 4 magnets, each 1.12 m long with a 48.4 x 48.4 mm aperture and operated at 1.6 kA. The kicker is constructed as a open-quotes Cclose quotes cross section magnet, in which ferrite and high-permittivity dielectric sections alternate. The dielectric blocks provide the capacity necessary for the nominally 25 Ω characteristic impedance of the travelling wave structure, but impose the practical limit on the peak voltage, and thus current, achievable. Computer studies to minimize local electric field enhancements resulted in a configuration capable of holding ∼ 50 kV, with adequate safety margin over the nominal 40 kV. Equivalent circuit analysis indicated the possibility of lowering the nominal voltage by operating mismatched into 20 Ω terminations without degrading the pulse shape. In this paper, the experience gained in the fabrication of the production units and the results from various single-unit tests and operation of four kickers with beam in the open-quotes Sextant Testclose quotes are reported

  6. Comparison of the Window-Frame RHIC-abort kicker with C-type Kicker

    Energy Technology Data Exchange (ETDEWEB)

    Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Hahn, H. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Meng, W. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Severance, Michael [Stony Brook Univ., NY (United States); McMahan, Brandon [Westhampton High School, NY (United States)

    2014-08-26

    The high intensity proton bunches (~2.5x1011 p/bunch ) circulating in RHIC increase the temperature of the ferrite-made RHIC-abort-kickers above the Curie point; as a result, the kickers cannot provide the required field to abort the beam at the beam dump. A team of experts in the CAD department worked on modifying the design of the window-frame RHIC-abort kicker to minimize the hysteresis losses responsible for the increase of the ferrite’s temperature. In this technical note we report some results from the study of two possible modifications of the window-frame RHIC-abort kicker, and we compare these results with those of a propose C-type RHIC-abort kicker. We also include an Appendix where we describe a method which may further reduce the hysteresis losses of the window-frame kicker.

  7. Comparison of the Window-Frame RHIC-abort kicker with C-type Kicker

    International Nuclear Information System (INIS)

    The high intensity proton bunches (~2.5x1011 p/bunch ) circulating in RHIC increase the temperature of the ferrite-made RHIC-abort-kickers above the Curie point; as a result, the kickers cannot provide the required field to abort the beam at the beam dump. A team of experts in the CAD department worked on modifying the design of the window-frame RHIC-abort kicker to minimize the hysteresis losses responsible for the increase of the ferrite's temperature. In this technical note we report some results from the study of two possible modifications of the window-frame RHIC-abort kicker, and we compare these results with those of a propose C-type RHIC-abort kicker. We also include an Appendix where we describe a method which may further reduce the hysteresis losses of the window-frame kicker.

  8. Low impedance kicker for high intensity accelerator

    International Nuclear Information System (INIS)

    A kicker magnet is one of the most important components in a synchrotron. To kick the beam from injection line to synchrotron orbit or opposite direction, a ferrite material is used to achieve a fast rise time. In case of a high intensity accelerator, the material is heated by beam current. Sometimes, it is reported that characteristic of material is changed when the material reaches Curie temperature. In this paper, we propose a low impedance kicker which consists of thin magnetic alloy ribbon. The structure of the new kicker is suitable to avoid to receive the beam effects. (author)

  9. Studies on beam extraction from the 1 GeV proton accumulator ring

    International Nuclear Information System (INIS)

    For the proposed Indian Spallation Neutron Source (ISNS), a 1 GeV proton Accumulator Ring (AR) is presently being designed at RRCAT. Two optics configurations of AR, namely FODO and Hybrid lattices are under consideration. Each lattice configuration has four superperiods. In this paper, preliminary studies on beam extraction from AR are presented for both the optics configurations. The extraction system will be accommodated in one of the long dispersion free straight sections. Bunch length of the proton beam in AR is 700 ns, and the revolution time of the bunch in AR is 1 ms. This leaves a gap of ∼300 ns for bunch extraction. The proton bunch will be extracted to Ring to Target Beam Transport (RTBT) line, with the help of fast kicker and septum magnets. In this paper, we present the details of the beam extraction scheme with suitable number of kicker magnets, and find out their optimal location and strength. Estimation of field error tolerances for kicker magnets is also presented. (author)

  10. Ferrite property effects on a fast kicker magnet

    International Nuclear Information System (INIS)

    The present J-PARC main ring (MR) injection system employs four lumped kicker magnets. Their task is to injection two bunches per cycle from the Rapid Cycling Synchrotron to the defined bucket in the MR. The operation must be loss-free to avoid any damage to the accelerator. However, the present injection kicker's field have relatively long rise time and large reflection field that do not satisfy the requirements of high beam power operation. Besides the upgrade of the main kickers, two small fast compensation kickers are being studied in parallel to correct the main kicker performance. Since high magnetization rates in magnetic materials are associated with considerable magnetic losses, high quality Nickel Zinc ferrite magnetic materials are required to ensure the performance of the compensation kickers. Therefore, the studies of ferrite materials effects on the parameters of both compensation kickers have carried out to optimize the design. (author)

  11. High power semiconductor switches in the 12 kV, 50 kA pulse generator of the SPS beam dump kicker system

    CERN Document Server

    Bonthond, J; Faure, P; Vossenberg, Eugène B

    2001-01-01

    Horizontal deflection of the beam in the dump kicker system of the CERN SPS accelerator is obtained with a series of fast pulsed magnets. The high current pulses of 50 kA per magnet are generated with capacitor discharge type generators which, combined with a resistive free-wheel diode circuit, deliver a critically damped half-sine current with a rise-time of 25 ms. Each generator consists of two 25 kA units, connected in parallel to a magnet via a low inductance transmission line.

  12. Stripline kicker for integrable optics test accelerator

    OpenAIRE

    Antipov, Sergey A.; Didenko, Alexander; Lebedev, Valeri; Valishev, Alexander

    2016-01-01

    We present a design of a stripline kicker for Integrable Optics Test Accelerator (IOTA). For its experimental program IOTA needs two full-aperture kickers, capable to create an arbitrary controllable kick in 2D. For that reason their strengths are variable in a wide range of amplitudes up to 16 mrad, and the pulse length 100 ns is less than a revolution period for electrons. In addition, the kicker should have a physical aperture of 40 mm for a proposed operation with proton beam, and an oute...

  13. The system of CSR beam Kicker trigger based on digital PLL

    International Nuclear Information System (INIS)

    For carrying out the precision trigger of Kick power, a system of beam kick trigger based on digital PLL has been designed, which is composed with phase-meter and NI's PXI modules PXI-6653 and PXI-6280. The NI Lab VIEW is used to design program. The system can quickly lock the frequency and adjust the phase, which satisfy the requirements of the trigger system of kick power. (authors)

  14. The kicker magnet system for TRISTAN Accumulation Ring injection

    International Nuclear Information System (INIS)

    The injection of electron beams to TRISTAN Accumulation Ring (AR) was started in November 1983 and the positron injection started in November 1985. For the injection of electron and positron beams to AR, the unique kicker system was developed. In the kicker power supply the charging to the main capacitor was done with the resonant charge system together with the auxiliary charging unit. The impedance matching circuit was added to the kicker magnet for getting the required current form with least reflecting oscillation. In this paper we report the performance of this kicker system. (author)

  15. AA injection kicker in its tank

    CERN Multimedia

    1980-01-01

    For single-turn injection of the antiprotons, a septum at the end of the injection line made the beam parallel to the injection orbit, and a quarter of a betatron-wavelength downstream a fast kicker corrected the angle. Kicker type: lumped delay line. PFN voltage 56 kV. Bending angle 7.5 mrad; kick-strength 0.9 Tm; fall-time 95%-5% in 150 ns. The injection orbit is to the left, the stack orbit to the far right. A fast shutter near the central orbit had to be closed before the kicker fired, so as to protect the stack core from being shaken by the kicker's fringe field. The shutter is shown in closed position.

  16. Development of Stripline Kickers for Low Emittance Rings: Application to the Beam Extraction Kicker for CLIC Damping Rings

    OpenAIRE

    Belver Aguilar, Carolina

    2015-01-01

    El descubrimiento del bosón de Higgs ha iniciado una nueva era en el LHC cuyo objetivo será medir las propiedades de dicho bosón con la mayor precisión posible. Sin embargo, dada la complejidad de los protones, compuestos por quarks y gluones, existe el consenso en la Física de Altas Energías de que el próximo colisionador será un colisionador electrón-positrón. Desde un punto de vista simplista, para que electrones y positrones colisionen a muy altas energías en un colisionador circular, la ...

  17. Measurements and Laboratory Tests on a Prototype Stripline Kicker for the CLIC Damping Rings

    CERN Document Server

    Belver-Aguilar, C; Toral, F; Barnes, MJ; Day, H

    2014-01-01

    The Pre-Damping Rings (PDRs) and Damping Rings (DRs) of CLIC are required to reduce the beam emittances to the small values required for the main linacs. The injection and extraction, from the PDRs and DRs, are performed by kicker systems. To achieve both low beam coupling impedance and reasonable broadband impedancematching to the electrical circuit, striplines have been chosen for the kicker elements. Prototype striplines have been built: tests and measurements of these striplines have started. The goal of these tests is to characterize, without beam, the electromagnetic response of the striplines. The tests have been carried out at CERN. To study the signal transmission through the striplines, the measured S-parameters have been compared with simulations. In addition, measurements of longitudinal beam coupling impedance, using the coaxial wire method, are reported and compared with simulations.

  18. Development of the beam extraction synchronization system at the Fermilab Booster

    International Nuclear Information System (INIS)

    The new beam extraction synchronization control system called “Magnetic Cogging” was developed at the Fermilab Booster and it replaces a system called “RF Cogging” as part of the Proton Improvement Plan (PIP).[1] The flux throughput goal for the PIP is 2.2×1017 protons per hour, which is double the present flux. The flux increase will be accomplished by doubling the number of beam cycles which, in turn, will double the beam loss in the Booster accelerator if nothing else is done. The Booster accelerates beam from 400 MeV to 8 GeV and extracts it to the Main Injector (MI) or Recycler Ring (RR). Cogging controls the beam extraction gap position which is created early in the Booster cycle and synchronizes the gap to the rising edge of the Booster extraction kicker and the MI/RR injection kicker. The RF Cogging system controls the gap position by changing only the radial position of the beam thus limiting the beam aperture and creating beam loss due to beam scraping. The Magnetic Cogging system controls the gap position with the magnetic field of the dipole correctors while the radial position feedback keeps the beam on a central orbit. Also with Magnetic Cogging the gap creation can occur earlier in the Booster cycle when the removed particles are at a lower energy. Thus Magnetic Cogging reduces the deposited energy of the lost particles (beam energy loss) and results in less beam loss activation. Energy loss was reduced by 40% by moving the gap creation energy from 700 MeV to 400 MeV when the Booster Cogging system was switched from RF Cogging to Magnetic Cogging in March 2015

  19. Development of the beam extraction synchronization system at the Fermilab Booster

    Science.gov (United States)

    Seiya, K.; Chaurize, S.; Drennan, C. C.; Pellico, W.; Sullivan, T.; Triplett, A. K.; Waller, A. M.

    2015-11-01

    The new beam extraction synchronization control system called "Magnetic Cogging" was developed at the Fermilab Booster and it replaces a system called "RF Cogging" as part of the Proton Improvement Plan (PIP).[1] The flux throughput goal for the PIP is 2.2×1017 protons per hour, which is double the present flux. The flux increase will be accomplished by doubling the number of beam cycles which, in turn, will double the beam loss in the Booster accelerator if nothing else is done. The Booster accelerates beam from 400 MeV to 8 GeV and extracts it to the Main Injector (MI) or Recycler Ring (RR). Cogging controls the beam extraction gap position which is created early in the Booster cycle and synchronizes the gap to the rising edge of the Booster extraction kicker and the MI/RR injection kicker. The RF Cogging system controls the gap position by changing only the radial position of the beam thus limiting the beam aperture and creating beam loss due to beam scraping. The Magnetic Cogging system controls the gap position with the magnetic field of the dipole correctors while the radial position feedback keeps the beam on a central orbit. Also with Magnetic Cogging the gap creation can occur earlier in the Booster cycle when the removed particles are at a lower energy. Thus Magnetic Cogging reduces the deposited energy of the lost particles (beam energy loss) and results in less beam loss activation. Energy loss was reduced by 40% by moving the gap creation energy from 700 MeV to 400 MeV when the Booster Cogging system was switched from RF Cogging to Magnetic Cogging in March 2015.

  20. Thermal Studies on the SPS Wideband Transverse Feedback Kicker

    CERN Document Server

    Roggen, Toon; Hofle, Wolfgang; Montesinos, Eric; CERN. Geneva. ATS Department

    2016-01-01

    As part of the SPS wideband transverse feedback system in the framework of the LHC Injector Upgrade (LIU) project, a wideband kicker design is being proposed. Vertical beam instabilities due to intensity dependent effects (electron cloud instability (ECI) and transverse mode coupling instability (TMCI)) are potentially suppressed by using a feedback system driving such a kicker system. One of the options for a kicker is a one meter long slotted-coaxial kicker, providing a substantial vertical kick strength (10ˉ5 –10ˉ4 eV.s/m) over a bandwidth ranging from nearly DC to 1 GHz. The necessary kick strength requires a total power of 4 kW. This note describes thermal studies that assisted in the material choice of the feedthroughs of the slotted-coaxial kicker and guided the design choices.

  1. Thermal Studies on the SPSWideband Transverse Feedback Kicker

    CERN Document Server

    Roggen, Toon; Hofle, Wolfgang; Montesinos, Eric; CERN. Geneva. ATS Department

    2016-01-01

    As part of the SPS wideband transverse feedback system in the framework of the LHC Injector Upgrade (LIU) project, a wideband kicker design is being proposed. Vertical beam instabilities due to intensity dependent effects (electron cloud instability (ECI) and transverse mode coupling instability (TMCI)) are potentially suppressed by using a feedback system driving such a kicker system. One of the options for a kicker is a one meter long slotted-coaxial kicker, providing a substantial vertical kick strength (10ˉ5 –10ˉ4 eV.s/m) over a bandwidth ranging from nearly DC to 1 GHz. The necessary kick strength requires a total power of 4 kW. This note describes thermal studies that assisted in the material choice of the feedthroughs of the slotted-coaxial kicker and guided the design choices.

  2. Stripline kicker for integrable optics test accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Antipov, Sergey A.; Didenko, Alexander; Lebedev, Valeri; Valishev, Alexander

    2016-06-30

    We present a design of a stripline kicker for Integrable Optics Test Accelerator (IOTA). For its experimental program IOTA needs two full-aperture kickers, capable to create an arbitrary controllable kick in 2D. For that reason their strengths are variable in a wide range of amplitudes up to 16 mrad, and the pulse length 100 ns is less than a revolution period for electrons. In addition, the kicker should have a physical aperture of 40 mm for a proposed operation with proton beam, and an outer size of 70 mm to fit inside existing quadrupole magnets to save space in the ring. Computer simulations using CST Microwave Studio show high field uniformity and wave impedance close to 50 {\\Omega}.

  3. Stripline kicker for integrable optics test accelerator

    CERN Document Server

    Antipov, Sergey A; Lebedev, Valeri; Valishev, Alexander

    2016-01-01

    We present a design of a stripline kicker for Integrable Optics Test Accelerator (IOTA). For its experimental program IOTA needs two full-aperture kickers, capable to create an arbitrary controllable kick in 2D. For that reason their strengths are variable in a wide range of amplitudes up to 16 mrad, and the pulse length 100 ns is less than a revolution period for electrons. In addition, the kicker should have a physical aperture of 40 mm for a proposed operation with proton beam, and an outer size of 70 mm to fit inside existing quadrupole magnets to save space in the ring. Computer simulations using CST Microwave Studio show high field uniformity and wave impedance close to 50 {\\Omega}.

  4. CLIC Pre-damping and Damping Ring Kickers: Initial Ideas to Achieve Stability Requirements

    CERN Document Server

    Barnes, M J; Uythoven, J

    2010-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity (1034-1035 cm-2s-1) and a nominal centre-of mass energy of 3 TeV: CLIC would complement LHC physics in the multi-TeV range. The CLIC design relies on the presence of Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve the very low emittance, through synchrotron radiation, needed for the luminosity requirements of CLIC. In order to limit the beam emittance blow-up due to oscillations the combined flat top ripple and droop of the field pulse, for the DR extraction kickers, must be less than 0.02 %. In addition, the allowed beam coupling impedance is also very low: a few Ohms longitudinally and a few MW/m transversally. This paper discusses initial ideas for achieving the demanding requirements for the PDR and DR kickers.

  5. Dual branch high voltage pulse generator for the beam extraction of the Large Hadron Collider

    CERN Document Server

    Bonthond, J; Ducimetière, L; Jansson, U; Vossenberg, Eugène B

    2002-01-01

    The LHC beam extraction kicker system, MKD, is composed of 15 fast kicker magnets per beam to extract the particles in one turn from the collider and to dispose them, after dilution, on an external absorber. Each magnet is powered by a separate pulse generator. The original single branch generator consisted of a discharge capacitor in series with a solid state closing switch left bracket 1 right bracket operating at 30 kV. In combination with a parallel freewheel diode stack this generator produced a current pulse of 2.7 mus rise time, 18.5 kA amplitude and about 1.8 ms fall time, of which only about 90 mus are needed to dump the beam. The freewheel diode circuit is equipped with a flat top current droop compensation network, consisting of a low voltage, low stray inductance, high current discharge capacitor. Extensive reliability studies have meanwhile suggested to further increase the operational safety of this crucial system by equipping each generator with two parallel branches. This paper presents the re...

  6. The LHC injection kicker magnet

    CERN Document Server

    Ducimetière, Laurent; Barnes, M J; Wait, G D

    2003-01-01

    Proton beams will be injected into LHC at 450 GeV by two kicker magnet systems, producing magnetic field pulses of approximately 900 ns rise time and up to 7.86 s flat top duration. One of the stringent design requirements of these systems is a flat top ripple of less than ± 0.5%. Both injection systems are composed of 4 travelling wave kicker magnets of 2.7 m length each, powered by pulse forming networks (PFN's). To achieve the required kick strength of 1.2 Tm, a low characteristic impedance has been chosen and ceramic plate capacitors are used to obtain 5 Omega. Conductive stripes in the aperture of the magnets limit the beam impedance and screen the ferrite. The electrical circuit has been designed with the help of PSpice computer modelling. A full size magnet prototype has been built and tested up to 60 kV with the magnet under ultra high vacuum (UHV). The pulse shape has been precision measured at a voltage of 15 kV. After reviewing the performance requirements the paper presents the magnet...

  7. THE COUPLING IMPEDANCE OF THE RHIC INJECTION KICKER SYSTEM

    International Nuclear Information System (INIS)

    IN THIS PAPER, RESULTS FROM IMPEDANCE MEASUREMENTS ON THE RHIC INJECTION KICKERS ARE REPORTED. THE KICKER IS CONFIGURED AS A ''C'' CROSS SECTION MAGNET WITH INTERLEAVED FERRITE AND HIGH-PERMITTIVITY DIELECTRIC SECTIONS TO ACHIEVE A TRAVELLING WAVE STRUCTURE. THE IMPEDANCE WAS MEASURED USING THE WIRE METHOD, AND ACCURATE RESULTS ARE OBTAINED BY INTERPRETING THE FORWARD SCATTERING COEFFICIENT VIA THE LONG-FORMULA. THE FOUR KICKERS WITH THEIR CERAMIC BEAM TUBES CONTRIBUE AT Z/N-0.22 OMEGA/RING IN THE INTERESTING FREQUENCY RANGE FROM 0.1 TO 1 BHZ, AND LESS ABOVE

  8. Longitudinal and transverse feedback kickers for the ALS

    International Nuclear Information System (INIS)

    We describe the development of electromagnetic kickers for coupled-bunch feedback systems at the ALS. Transverse kickers are of a stripline design with one kicker per plane, operating in the baseband, 10 kHz to 250 MHz. Longitudinal lockers are of a coaxial design with electrodes paired in series operating over the band 1.00 to 1.25 GHz. Operating-band measurements and parasitic impedance measurements are presented. Power levels from beam induced signals are presented. Fabrication techniques are discussed

  9. Longitudinal and transverse feedback kickers for the ALS

    Energy Technology Data Exchange (ETDEWEB)

    Corlett, J.N.; Johnson, J.; Lambertson, G.; Voelker, F.

    1994-06-01

    We describe the development of electromagnetic kickers for coupled-bunch feedback systems at the ALS. Transverse kickers are of a stripline design with one kicker per plane, operating in the baseband, 10 kHz to 250 MHz. Longitudinal lockers are of a coaxial design with electrodes paired in series operating over the band 1.00 to 1.25 GHz. Operating-band measurements and parasitic impedance measurements are presented. Power levels from beam induced signals are presented. Fabrication techniques are discussed.

  10. Design of control system for Kicker magnet power supply

    International Nuclear Information System (INIS)

    The heavy ion research facility at Lanzhou cooler storage ring (HIRFL-CSR) includes several parts of extraction and injection systems. Among these parts the extraction part of CSRm and the injection part of CSRe are the most important parts and the time control precision of them affects the beam's injection and extraction efficiency directly. In this paper the advanced ARM + FPGA technology was applied to make a precise control of the Kicker control power supply system and the control accuracy reached to ns. ARM was mainly used to upload and download the control data and the timing sequence control was mainly completed by the program on FPGA. All the control signal of remote timing was transferred through optic fiber, and at the same time, the digital potentiometer was used to fix the voltage of the power supply system with the given accuracy of 0.1%. (authors)

  11. Kicker magnet design

    International Nuclear Information System (INIS)

    In this paper, the kicker magnet is studied by use of the program POISSON. For using the dc-code POISSON in the ac problem of the kicker magnet, an approximation of the ac effects is made, this simplifying the ac problem into a dc problem. The study of the magnet is taken in two steps: assuming the γ of the ferrite material is fixed in the calculation to get a preliminary design of the magnet; using the real B /minus/ H curve of the CMD5005 ferrite material in the calculation to get the final design of the magnet. The stored energy, the excitation curve and the excitation efficiency of the kicker magnet are also discussed. 10 figs., 7 tabs

  12. Upgrade of the LHC Injection Kicker Magnets

    CERN Document Server

    Barnes, M J; Baglin, V; Bregliozzi, G; Caspers, F; Calatroni, S; Day, H; Ducimetière, L; Garlaschè, M; Gomes Namora, V; Jimenez, J M; Magnin, N; Mertens, V; Métral, E; Salvant, B; Taborelli, M; Uythoven, J; Weterings, W

    2013-01-01

    Two LHC injection kicker systems, each comprising 4 magnets per ring, produce a kick of 1.3 T·m with a rise-time of less than 900 ns and a flattop ripple of less than ±0.5%. A beam screen is placed in the aperture of each magnet, to provide a path for the image current of the LHC beam and screen the ferrite yoke against wake fields. The screen consists of a ceramic tube with conductors in the inner wall. The initially implemented beam screen ensured a low rate of electrical breakdowns and an adequately low beam coupling impedance. Operation with increasingly higher intensity beams, stable for many hours at a time, has resulted in substantial heating of the ferrite yoke, sometimes requiring cool-down over several hours before the LHC can be refilled. During the long shutdown in 2013/2014 all eight kicker magnets will be upgraded with an improved beam screen and an increased emissivity of the vacuum tank. In addition equipment adjacent to the injection kickers and various vacuum components will be modified to...

  13. Optimization of speed-up network component values for the 30 Ω resistively terminated prototype kicker magnet

    International Nuclear Information System (INIS)

    Kicker magnets are required for all ring-to-ring transfers in the 5 rings of the proposed KAON factory synchrotron. The kick must rise from 1% to 99% of full strength during the time interval of gaps created in the beam (80 ns to 160 ns) so that the beam can be extracted with minimum losses. In order to achieve the specified rise-time and open-quote flatness close-quote for the kick it is necessary to utilize speed-up networks, comprising a capacitor and a resistor, in the electrical circuit. Speed-up networks may be connected electrically on both the input and output of the kicker magnet. In addition it is advantageous to connect a open-quote speed-up close-quote network on the input of the resistive terminator(s). A sequence which may minimize the number of mathematical simulations required to optimize the values of the 8 possible speed-up components is presented. PE2D has been utilized to determine inductance and capacitance values for the resistive terminator; this data has been used in PSpice transient analyses. Results of the PE2D predictions are also presented. The research has culminated in a predicted kick rise time (1% to 99%) of less than 50 ns for a TRIUMF 10 cell prototype kicker magnet. The proposed improvements are currently being implemented on our prototype kicker system

  14. SPS injection kicker

    CERN Multimedia

    1975-01-01

    The 5-cell, lumped-delay-line structure of the first-generation SPS injection kickers. For a more detailed description see 7502072X. See also 7502073X and Annual Report 1975, p.162. To the left: Roland Tröhler; to the right: Giacomo Busetta.

  15. Simulation of Transient Effects of Beam-Transverse Feedback Interaction with Application to the Extraction of the CNGS Beam from the SPS

    CERN Document Server

    Höfle, Wolfgang

    2005-01-01

    For existing and future high energy proton accelerators, transverse feedback systems play an essential role in supplying the physics experiments with high intensity beams at low emittances. We developed a simulation model to study the interaction between beam and transverse feedback system in detail, bunch-by-bunch and turn-by-turn, considering the technical implementation at the SPS [1]. A numerical model is used as the non linear behaviour (saturation) and limited bandwidth of the feedback system, as well as the transient nature at injection and extraction, complicates the analysis. The model is applied to the practical case of the CNGS beam [2] in the SPS accelerator. This beam will be ejected from the SPS in two batches causing residual oscillations by kicker ripples on the second batch. This second batch continues to circulate for 50 ms (about 2170 turns) after the first batch has been extracted and oscillations are planned to be damped by the feedback system.

  16. MTN magnet for the SPS extracted beam.

    CERN Multimedia

    1976-01-01

    This type of dipole magnet was used in the extracted beam lines of the North Area. It shows an opening for three different proton beam lines: a primary extracted proton beam, split by an upstream magnetic beam splitter (see photo 7612017) into three separated beams passes through different parts of its aperture: right, left up, left down. These magnets were designed to be concrete-insulated for radiation resistance. F. Streun stands on the right.

  17. Simulation studies for ion beam extraction systems

    Energy Technology Data Exchange (ETDEWEB)

    Abdelrahman, M.M.; Zakhary, S.G. [Atomic Energy, Cairo (Egypt). Nuclear Research Center. Accelerators and Ion Sources Dept.], e-mail: moustafa82003@yahoo.com

    2009-06-15

    The characteristics of the ion beam extracted from an ion sources were investigated using computer code SIMION 3 D Version 7.0. It has been used to evaluate the extraction system in order to produce an ion beam with high current and low beam emittance. The results show that the shape of the extraction electrode plays an important role in ion beam formation. Comparison has been made between two extraction systems, Pierce extraction electrode and spherical extraction electrode. The results show that the spherical extraction system yields ion extraction beam with lower emittance and radius than that the Pierce system. The simulation can provide the basis for optimizing the extraction system and the acceleration gap for ion source. (author)

  18. RF Modeling of a Helical Kicker for Fast Chopping

    Energy Technology Data Exchange (ETDEWEB)

    Awida, Mohamed [Fermilab; Chen, Alex [Fermilab; Khabiboulline, Timergali [Fermilab; Saewert, Gregory [Fermilab; Yakovlev, Vyacheslav [Fermilab

    2015-06-01

    High intensity proton particle accelerators that supports several simultaneous physics experiments requires sharing the beam. A bunch by bunch beam chopper system located after the Radio Frequency Quadrupole (RFQ) is required in this case to structure the beam in the proper bunch format required by the several experiments. The unused beam will need to be kicked out of the beam path and is disposed in a beam dumb. In this paper, we report on the RF modeling results of a proposed helical kicker. Two beam kickers constitutes the proposed chopper. The beam sequence is formed by kicking in or out the beam bunches from the streamline. The chopper was developed for Project X Injection Experiment (PXIE).

  19. Report on kickers working group discussion

    International Nuclear Information System (INIS)

    This paper is a summary of the working group discussion on kicker magnet design. Topics included: electric field deflectors, B-I tracking, kicker design, coupling impedance, Kaon factory kicker needs, the new lattices, and preliminary proposals for kickers for Kaon factory

  20. Control System for the LLNL Kicker Pulse Generator

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J A; Anaya, R M; Cook, E G; Lee, B S; Hawkins, S A

    2002-06-18

    A solid-state high voltage pulse generator with multi-pulse burst capability, very fast rise and fall times, pulse width agility, and amplitude modulation capability for use with high speed electron beam kickers has been designed and tested at LLNL. A control system calculates a desired waveform to be applied to the kicker based on measured electron beam displacement then adjusts the pulse generators to provide the desired waveform. This paper presents the design of the control system and measure performance data from operation on the ETA-11 accelerator at LLNL.

  1. Simulation of Transient Beam-Feedback Interaction and Application to Extraction of CNGS Beam from the SPS

    CERN Document Server

    Vogel, E

    2004-01-01

    For present and future high energy proton accelerators, such as the LHC, transverse feedback systems play an essential role in supplying the physics experiments with high intensity beams at low emittances. We developed a simulation model to study the interaction between beam and transverse feedback system in detail, bunch-by-bunch and turn-by-turn, considering the real technical implementation of the latter. A numerical model is used as the non linear behaviour (saturation) and limited bandwidth of the feedback system, as well as the transient nature at injection and extraction, complicates the analysis. The model is applied to the practical case of the CNGS beam in the SPS accelerator. This beam will be ejected from the SPS in two batches causing residual oscillations by kicker ripples on the second batch. This second batch continues to circulate for 2167 turns after the first batch has been extracted and oscillations are planned to be damped by the feedback system. The model can be extended to examine trans...

  2. AA, stochastic precooling kicker

    CERN Multimedia

    1980-01-01

    The freshly injected antiprotons were subjected to fast stochastic "precooling", while a shutter shielded the deeply cooled antiproton stack from the violent action of the precooling kicker. In this picture, the injection orbit is to the left, the stack orbit to the far right, the separating shutter is in open position. After several seconds of precooling (in momentum and in the vertical plane), the shutter was opened briefly, so that by means of RF the precooled antiprotons could be transferred to the stack tail, where they were subjected to further cooling in momentum and both transverse planes, until they ended up, deeply cooled, in the stack core. The fast shutter, which had to open and close in a fraction of a second was an essential item of the cooling scheme and a mechanical masterpiece. Here the shutter is in the open position. The precooling pickups were of the same design, with the difference that the kickers had cooling circuits and the pickups not. 8401150 shows a precooling pickup with the shutte...

  3. Kickers and power supplies for the Fermilab Tevatron I antiproton source

    International Nuclear Information System (INIS)

    The Fermilab Antiproton Source Accumulator and Debuncher rings require 5 kickers in total. These range in design from conventional ferrite delay line type magnets, with ceramic beam tubes to mechanically complex shuttered kickers situated entirely in the Accumulator Ring's 10-10 torr vacuum. Power supplies are thyratron switched pulse forming networks that produce microsecond width pulses of several kiloamps with less than 30 nanoseconds rise and fall times. Kicker and power supply design requirements for field strength, vacuum, rise and fall time, timing and magnetic shielding of the stacked beam in the accumulator by the eddy current shutter will be discussed. 8 refs., 3 figs., 2 tabs

  4. The coupling impedance of the RHIC injection kicker system

    International Nuclear Information System (INIS)

    In this paper, results from impedance measurements on the RHIC injection kickers are reported. The kicker is configured as a ''C'' cross section magnet with interleaved ferrite and high-permittivity dielectric sections to achieve a travelling wave structure. The impedance was measured using the wire method in which a resistive match provides a smooth transition from the network analyzer to the reference line in the set-up. Accurate results are obtained by interpreting the forward scattering coefficient via the log-formula. The four kickers with their ceramic beam tubes contribute a Z/n=0.22 Ω/ring in the interesting frequency range from 0.1 to 1 GHz, and less above. At frequencies above ∼ 100 MHz, the impedance is ferrite dominated and not affected by the kicker terminations. Below 100 MHz, the Blumlein pulser with the ∼75 m feeding cables is visible in the impedance but makes no significant contribution to the results. The measurements show that the kicker coupling impedance is tolerable without the need for impedance reducing measures

  5. The coupling impedance of the RHIC injection kicker system

    International Nuclear Information System (INIS)

    In this paper, results from impedance measurements on the RHIC injection kickers are reported. The kicker is configured as a open-quotes Cclose quotes cross section magnet with interleaved ferrite and high-permittivity dielectric sections to achieve a travelling wave structure. The impedance was measured using the wire method in which a resistive match provides a smooth transition from the network analyzer to the reference line in the set-up. Accurate results are obtained by interpreting the forward scattering coefficient via the log-formula. The four kickers with their ceramic beam tubes contribute a Z/n = 0.22 Ω/ring in the interesting frequency range from 0.1 to 1 GHz, and less above. At frequencies above ∼100 MHZ, the impedance is ferrite dominated and not affected by the kicker terminations. Below 100 MHz, the Blumlein pulser with the ∼75 m feeding cables is visible in the impedance but makes no significant contribution to the results. The measurements show that the kicker coupling impedance is tolerable without the need for impedance reducing measures

  6. Slot-type kicker for the AA stochastic cooling

    CERN Multimedia

    Photographic Service

    1979-01-01

    A "slotted transmission line" structure was used for both pickups and the kicker of one of the stochastic cooling systems of the Antiproton Accumulator (AA). They served for the cooling of the high-density stack, in momentum and in both transverse planes. In the beginning in a single band, 1-2 GHz, later in 3 bands, 1-2, 2-4 and 4-8 GHz. The kicker of the first generation, shown here, was located where the dispersion was zero and the beam size small, and thus had a quadratic cross-section. The pickups were rectangular and wider in the horizontal plane. See also 7906193

  7. Initial measurements on a prototype inductive adder for the CLIC kicker systems

    CERN Document Server

    Holma, Janne

    2013-01-01

    The CLIC study is exploring the scheme for an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings will produce, through synchrotron radiation, ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the damping ring kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the extraction kickers of the DRs are particularly demanding: the flattops of the pulses must be ±12.5 kV with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications. To achieve ultra-flat pulses with a fast rise time the output impedance of the inductive adder needs to be well matched to the system impedance. The parasitic circuit elements of the inductive adder have a significant effect upon the output impedance and these values are very difficult to calculate accurately analytically. To predict these paramet...

  8. Measurements on Prototype Inductive Adders with Ultra-Flat-Top Output Pulses for CLIC DR Kickers

    CERN Document Server

    Holma, J; Belver-Aguilar, C

    2014-01-01

    The CLIC study is investigating the technical feasibility of an electron-positron collider with high luminosity and a nominal centre-of-mass energy of 3 TeV. The CLIC pre-damping rings and damping rings (DRs) will produce ultra-low emittance beam with high bunch charge. To avoid beam emittance increase, the DR kicker systems must provide extremely flat, high-voltage, pulses. The specifications for the DR extraction kickers call for a 160 ns duration flat-top pulses of ±12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 % (±2.5 V). An inductive adder is a very promising approach to meeting the specifications because this topology allows the use of both passive and analogue modulation methods to adjust the output waveform. Recently, two five-layer, 3.5 kV, prototype inductive adders have been built at CERN. The first of these has been used to test the passive and active analogue modulation methods to compensate voltage droop and ripple of the output pulses. Pulse waveforms have been reco...

  9. Beam stripping extraction from the VINCY cyclotron

    Directory of Open Access Journals (Sweden)

    Ristić-Đurović Jasna L.

    2006-01-01

    Full Text Available The extraction system of a cyclotron guides an ion beam from a spiral acceleration orbit, through an extraction trajectory, into a high energy transport line. The two methods commonly used to direct an ion into the extraction path are deflection, by the electric field of an electrostatic deflector, and ion stripping, by a thin carbon foil. Compared to the electrostatic deflector system, the stripping extraction provides a fast and easy change of the extracted ion energy and is easier to manufacture operate, and maintain. However, the extraction trajectory and dynamics of an ion beam after stripping are highly dependant on the ion energy and specific charge. Thus, when a multipurpose machine such as the VINCY Cyclotron is concerned, it is far from easy to deliver a variety of ion beams into the same high energy transport line and at the same time preserve a reasonable compactness of the extraction system. The front side stripping extraction system of the VINCY Cyclotron provides high (~70 MeV and mid (~30 MeV energy protons, as well as a number of heavy ions in broad energy ranges. The back side stripping extraction system extracts low energy protons (~18 MeV and enables their simultaneous use with high energy protons at the front side of the machine.

  10. SPS Beam Steering for LHC Extraction

    CERN Document Server

    Gianfelice Wendt, E; Cornelis, K; Norderhaug Drosdal, L; Goddard, B; Kain, V; Meddahi, M; Papaphilippou, Y; Wenninger, J

    2014-01-01

    Beside producing beams for fixed target operation, the CERN Super Proton Synchrotron (SPS) accelerates beams for injection into the Large Hadron Collider (LHC). During the 2012-2013 run drifts of the extracted beam horizontal trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. The feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, has been therefore investigated. The challenges and constraints related to the implementation of such a correction in the SPS are described. Simulation results are presented and a possible operational steering strategy is proposed. As the observed drift is mainly horizontal, the horizontal plane only will be considered.

  11. An integrating current transformer for fast extraction from the HIRFL-CSR main ring

    Science.gov (United States)

    Wu, Jun-Xia; Zheng, Jian-Hua; Zhao, Tie-Cheng; Mao, Rui-Shi; Yin, Yan; Yuan, You-Jin; Yang, Jian-Cheng

    2010-01-01

    For any experiment that uses the beam of an accelerator, monitoring the beam intensity is always an important concern. It is particularly useful if one can continuously measure the beam current without disturbing the beam. We report here on test experiments for an Integrating Current Transformer (ICT) used to measure fast extraction beams from the HIRFL-CSR main ring (CSRm). The laboratory tests and beam intensity measurement results are presented in this paper. The influence of the kicker noise is also analyzed.

  12. Dynamic devices: A primer on pickups and kickers

    International Nuclear Information System (INIS)

    A charged-particle beam generates electromagnetic fields which in turn interact with the beam's surroundings. These interactions can produce fields which act back on the beam itself, or, if the ''surroundings'' are of suitably designed form (e.g., sensing electrodes with electrical connection to the ''outside world''), can provide information on various properties of the beam; such electrodes are generally known as pickups. Similarly, charged- particle beams respond to the presence of externally imposed electromagnetic fields; devices used to generate such fields are generally known as kickers. As we shall show, the behavior of an electrode system when it functions as a pickup is intimately related to its behavior as a kicker. A number of papers on pickup behavior have appeared in recent years in most of which the primary emphasis has been on beam instrumentation; there have also been several workshops on the subject. There have been several papers which have treated both pickup and kicker behavior of a particular electrode system, but this has been done in the context of discussing a specialized application, such as a stochastic cooling system. The approach in the present paper is similar to that of earlier works by one of the authors, which is to provide a unified treatment of pickup and kicker behavior, and, it is hoped, to give the reader an understanding which is both general and fundamental enough to make the above references easily accessible to him. As implied by the revised title, we have done the re-writing with the non-expert in mind. We have made the introduction both lengthier and more detailed, and done the same with much of the explanatory material and discussion

  13. AGS Resonant Extraction with High Intensity Beams

    International Nuclear Information System (INIS)

    The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7 x 1013 protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), they continue to run with low losses and high quality low modulation continuous current beams. Learning to extract and transport these higher intensity beams has required a process of careful modeling and experimentation. They have had to learn how to correct for various instabilities and how to better match extraction and the transport lines to the higher emittance beams being accelerated in the AGS. Techniques employed include ''RF'' methods to smooth out momentum distributions and fine structure. They will present results of detailed multi-particle tracking modeling studies which enabled them to develop a clear understanding of beam loss mechanisms in the transport and extraction process. They report on their status, experiences, and the present understanding of the intensity limitations imposed by resonant extraction and transport to fixed target stations

  14. AGS RESONANT EXTRACTION WITH HIGH INTENSITY BEAMS.

    Energy Technology Data Exchange (ETDEWEB)

    AHRENS,L.; BROWN,K.; GLENN,J.W.; ROSER,T.; TSOUPAS,N.; VANASSELT,W.

    1999-03-29

    The Brookhaven AGS third integer resonant extraction system allows the AGS to provide high quality, high intensity 25.5 GeV/c proton beams simultaneously to four target stations and as many as 8 experiments. With the increasing intensities (over 7 x 10{sup 13} protons/pulse) and associated longer spill periods (2.4 to 3 seconds long), we continue to run with low losses and high quality low modulation continuous current beams.[1] Learning to extract and transport these higher intensity beams has required a process of careful modeling and experimentation. We have had to learn how to correct for various instabilities and how to better match extraction and the transport lines to the higher emittance beams being accelerated in the AGS. Techniques employed include ''RF'' methods to smooth out momentum distributions and fine structure. We will present results of detailed multi-particle tracking modeling studies which enabled us to develop a clear understanding of beam loss mechanisms in the transport and extraction process. We will report on our status, experiences, and the present understanding of the intensity limitations imposed by resonant extraction and transport to fixed target stations.

  15. Amplitude Control of Solid-State Modulators for Precision Fast Kicker Applications

    Energy Technology Data Exchange (ETDEWEB)

    Watson, J A; Anaya, R M; Caporaso, G C; Chen, Y J; Cook, E G; Lee, B S; Hawkins, A

    2002-11-15

    A solid-state modulator with very fast rise and fall times, pulse width agility, and multi-pulse burst and intra-pulse amplitude adjustment capability for use with high speed electron beam kickers has been designed and tested at LLNL. The modulator uses multiple solid-state modules stacked in an inductive-adder configuration. Amplitude adjustment is provided by controlling individual modules in the adder, and is used to compensate for transverse e-beam motion as well as the dynamic response and beam-induced steering effects associated with the kicker structure. A control algorithm calculates a voltage based on measured e-beam displacement and adjusts the modulator to regulate beam centroid position. This paper presents design details of amplitude control along with measured performance data from kicker operation on the ETA-II accelerator at LLNL.

  16. A waveguide overloaded cavity kicker for the HLS II longitudinal feedback system

    CERN Document Server

    Li, Wubin; Sun, Baogen; Wu, Fangfang; Xu, Wei; Lu, Ping; Yang, Yongliang

    2013-01-01

    In the upgrade project of Hefei Light Source (HLS II), a new digital longitudinal bunch-by-bunch feedback system will be developed to suppress the coupled bunch instabilities in the storage ring effectively. We design a new waveguide overloaded cavity longitudinal feedback kicker as the feedback actuator. The beam pipe of the kicker is racetrack shape so as to avoid a transition part to the octagonal vacuum chamber. The central frequency and the bandwidth of the kicker have been simulated and optimized to achieve design goals by the HFSS code. The higher shunt impedance can be obtained by using a nose cone to reduce the feedback power requirement. Before the kicker cavity was installed in the storage ring, a variety of measurements were carried out to check its performance. All these results of simulation and measurement are presented.

  17. Negative ion beam extraction in ROBIN

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Gourab, E-mail: bansal@ipr.res.in [Institute for Plasma Research (IPR), Bhat, Gandhinagar, Gujarat 382428 (India); Gahlaut, Agrajit; Soni, Jignesh; Pandya, Kaushal; Parmar, Kanu G.; Pandey, Ravi; Vuppugalla, Mahesh; Prajapati, Bhavesh; Patel, Amee; Mistery, Hiren [Institute for Plasma Research (IPR), Bhat, Gandhinagar, Gujarat 382428 (India); Chakraborty, Arun; Bandyopadhyay, Mainak; Singh, Mahendrajit J.; Phukan, Arindam; Yadav, Ratnakar K.; Parmar, Deepak [ITER-India, Institute for Plasma Research, A-29, Sector 25, GIDC, Gandhinagar, Gujarat 380025 (India)

    2013-10-15

    Highlights: ► A RF based negative hydrogen ion beam test bed has been set up at IPR, India. ► Ion source has been successfully commissioned and three campaigns of plasma production have been carried out. ► Extraction system (35 kV) has been installed and commissioning has been initiated. Negative ion beam extraction is immediate milestone. -- Abstract: The RF based single driver −ve ion source experiment test bed ROBIN (Replica Of BATMAN like source in INDIA) has been set up at Institute for Plasma Research (IPR), India in a technical collaboration with IPP, Garching, Germany. A hydrogen plasma of density 5 × 10{sup 12} cm{sup −3} is expected in driver region of ROBIN by launching 100 kW RF power into the driver by 1 MHz RF generator. The cesiated source is expected to deliver a hydrogen negative ion beam of 10 A at 35 kV with a current density of 35 mA/cm{sup 2} as observed in BATMAN. In first phase operation of the ROBIN ion source, a hydrogen plasma has been successfully generated (without extraction system) by coupling 80 kW RF input power through a matching network with high power factor (cos θ > 0.8) and different plasma parameters have been measured using Langmuir probes and emission spectroscopy. The plasma density of 2.5 × 10{sup 11} cm{sup −3} has been measured in the extraction region of ROBIN. For negative hydrogen ion beam extraction in second phase operation, extraction system has been assembled and installed with ion source on the vacuum vessel. The source shall be first operated in volume mode for negative ion beam extraction. The commissioning of the source with high voltage power supply has been initiated.

  18. Ion Beam Extraction by Discrete Ion Focusing

    DEFF Research Database (Denmark)

    2010-01-01

    An apparatus (900) and methods are disclosed for ion beam extraction. In an implementation, the apparatus includes a plasma source (or plasma) (802) and an ion extractor (804). The plasma source is adapted to generate ions and the ion extractor is immersed in the plasma source to extract a fraction......) in the space-charge surrounding the ion extractor. The strongly curved potential distribution focuses the extracted ions towards an opening (814) on a surface of the biased electrode thereby resulting in an ion beam....... of the generated ions. The ion extractor is surrounded by a space charge (810) formed at least in part by the extracted ions. The ion extractor includes a biased electrode (806) forming an interface with an insulator (808). The interface is customized to form a strongly curved potential distribution (812...

  19. Frequency response of slow beam extraction process

    International Nuclear Information System (INIS)

    A servo control system has been incorporated into the practical slow extraction system in order to stabilize the spill structure less than a few kHz. Frequency responses of the components of the servo-spill control system and the open-loop frequency response were measured. The beam transfer function of the slow extraction process was derived from the measured data and approximated using a simple function. This is utilized to improve the performance of the servo-loop. (author)

  20. Single-bunch kicker pulser

    International Nuclear Information System (INIS)

    The single-bunch kicker magnet is powered by a capacitor discharge pulser. The ferrite-core magnet is used to kick out one of twelve proton bunches circulating in the AGS (Alternating Gradient Synchrotron) into the experimental area. The magnet current pulse has a half-sinusoid shape, with a peak current of 2800 A. The pulse current rises and falls to zero, with minimum undershoot, in 410 nsec to minimize effects on adjacent bunches. The magnet inductance is 1.0 μHy. The pulser is mounted on the kicker magnet in the AGS ring, and is exposed to ionizing radiation. The HVDC power supply, controls, monitoring, and auxiliary circuits are housed approximately 300 feet away external to the ring. A two-gap thyratron is used to discharge the energy storage capacitor. Two hydrogen diodes are series connected to function as an inverse diode

  1. Single-bunch kicker pulser

    Energy Technology Data Exchange (ETDEWEB)

    Frey, W.W.

    1983-01-01

    The single-bunch kicker magnet is powered by a capacitor discharge pulser. The ferrite-core magnet is used to kick out one of twelve proton bunches circulating in the AGS (Alternating Gradient Synchrotron) into the experimental area. The magnet current pulse has a half-sinusoid shape, with a peak current of 2800 A. The pulse current rises and falls to zero, with minimum undershoot, in 410 nsec to minimize effects on adjacent bunches. The magnet inductance is 1.0 ..mu..Hy. The pulser is mounted on the kicker magnet in the AGS ring, and is exposed to ionizing radiation. The HVDC power supply, controls, monitoring, and auxiliary circuits are housed approximately 300 feet away external to the ring. A two-gap thyratron is used to discharge the energy storage capacitor. Two hydrogen diodes are series connected to function as an inverse diode.

  2. Time profile of the slowly extracted beam

    CERN Document Server

    Pullia, M

    1997-01-01

    An important spin-off from accelerators is the use of synchrotrons for cancer therapy. For this application a precise control of the slow extraction is needed to satisfy the medical specifications for the online measurement and control of the delivered dose. This has led to a renewed interest in the basic theory of third-order resonance extraction. In the present paper, an analytic study of the time profile of the extracted beam is made by first considering the time profile of an elementary strip of monoenergetic particles from the side of the shrinking stable triangle. This basic result is then used to predict the characteristics of the spills for the most common extraction configurations. The influence of ripples whose period is comparable to the transit time of a particle in the resonance is also analyzed. Simulations of the extraction process that confirm the analytic study are included.

  3. AN OVERVIEW OF HIGH VOLTAGE DIELECTRIC MATERIAL FOR TRAVELING WAVE KICKER MAGNET APPLICATION

    International Nuclear Information System (INIS)

    Pulsed high power fast kickers are being used to change beam trajectories in particle accelerators. The fast rise and fall time of pulse waveform demands a transmission line structure for the kicker deflector design. The ideal design will be parallel metal plates. However, it uses very long straight sections to achieve the required deflection. In accelerators with constrained straight sections, high permeability materials such as ferrite have to be used to gain deflection efficiency. The transmission line kicker magnet is also referred as traveling wave kicker magnet. Its construction is based on distributed 1-C cells along the longitudinal direction. The magnetic cells and capacitive cells are interleaved to simulate the characteristic impedance of a transmission line to minimize pulse reflection, and provide adequate frequency bandwidth to transmit the kicker pulse with fast rise and fall time. The magnetic cells are usually made of ferrite ceramics, but the capacitive cells have been made with different materials. For traveling wave kickers with higher impedance, the parallel plate vacuum capacitor has been used in CERN and KEK design. Others have used ceramic capacitors, printed circuit boards, and high permittivity ceramics as the capacitive cell. The high dielectric material has the advantage of compactness for low impedance kicker magnet construction. It continues to be very attractive for future kicker magnet applications. The high voltage phenomena associated with high dielectric ceramic materials have been widely reported in many industrial application areas. Their implication in the traveling wave magnet application has to be well understood. In this presentation, the areas requiring further quantitative study will be outlined

  4. An overview of high voltage dielectric material for traveling wave kicker magnet application

    International Nuclear Information System (INIS)

    Pulsed high power fast kickers are being used to change beam trajectories in particle accelerators. The fast rise and fall time of pulse waveform demands a transmission line structure for the kicker deflector design. The ideal design will be parallel metal plates. However, it uses very long straight sections to achieve the required deflection. In accelerators with constrained straight sections, high permeability materials such as ferrite have to be used to gain deflection efficiency. The transmission line kicker magnet is also referred as traveling wave kicker magnet. Its construction is based on distributed L-C cells along the longitudinal direction. The magnetic cells and capacitive cells are interleaved to simulate the characteristic impedance of a transmission line to minimize pulse reflection, and provide adequate frequency bandwidth to transmit the kicker pulse with fast rise and fall time. The magnetic cells are usually made of ferrite ceramics, but the capacitive cells have been made with different materials. For traveling wave kickers with higher impedance, the parallel plate vacuum capacitor has been used in CERN and KEK design. Others have used ceramic capacitors, printed circuit boards, and high permittivity ceramics as the capacitive cell. The high dielectric material has the advantage of compactness for low impedance kicker magnet construction. It continues to be very attractive for future kicker magnet applications. The high voltage phenomena associated with high dielectric ceramic materials have been widely reported in many industrial application areas. Their implication in the traveling wave magnet application has to be well understood. In this presentation, the areas requiring further quantitative study will be outlined

  5. Impedance of a slotted-pipe kicker

    Energy Technology Data Exchange (ETDEWEB)

    Feng Zhou [Academia Sinica, Beijing, BJ (China). Inst. of High Energy Physics

    1996-08-01

    This paper introduces the principle of a new slotted kicker simply, which is made by using vacuum pipe itself with proper slits as current conductors, and then, presents a rough estimation of its longitudinal and transverse impedance, respectively. Calculation shows that its impedance is reduced significantly compared to our present air-coil kicker. (author)

  6. An Over-damped Cavity Longitudinal Kicker for the PEP-II LER

    CERN Document Server

    McIntosh, P

    2003-01-01

    Both rings of PEP-II use drift tube kickers in the longitudinal bunch-by-bunch feedback system. Efforts are now underway to increase the stored beam currents and luminosity of PEP-II, and beam-induced heating of these structures, particularly in the Low Energy Ring (LER) is of concern. An alternative kicker design based on the over-damped cavity kicker, first developed by INFN-Frascati is being built for PEP-II. This low loaded Q (or wide bandwidth) structure is fed by a network of ridged waveguides coupled to a simple pill-box cavity. Beam induced RF power is also coupled out of the cavity to external loads, so that the higher order modes (HOMs) excited in the structure are well-damped. This paper details the kicker design for PEP-II and discusses some of the design trade-offs between shunt impedance and bandwidth, as well as the influence of the feedthroughs on the kicker parameters. Estimates of the expected power deposition in the cavity are also provided.

  7. AGS new fast extraction system and the single bunch extraction test

    Energy Technology Data Exchange (ETDEWEB)

    Weng, W.T.

    1983-01-01

    For the neutrino physics program and for the CBA injection, a new fast extraction system has been implemented to improve the extraction efficiency and the quality of the extracted beam. Central to the new system is a new fast kicker, placed at the H5 straight section, capable of rising between bunches, t/sub r/ < 170 nsec, and staying constant for 2.6 ..mu..sec with flat top ripple less than +-1.5%. So far, the system has been operated for longer than 3000 hours and routinely extracts 10/sup 13/ ppp at 99% efficiency. Experiment 745 on QCD test requires a single AGS bunch of 40 nsec. For this purpose another fast kicker was placed at the E5 straight section and powered by a new pulser to produce a half sinusoidal pulse with both a rise and fall time of 200 nsec. A single AGS bunch was extracted through the slow beam channel at 22 GeV/c leaving the remaining 11 bunches undisturbed which continued to be accelerated to 29.4 GeV/c and extracted by the H5 kicker through the fast beam channel. Because the ring circumference ratio of CBA to the AGS is 4-3/4, some of the injected beam from the AGS has to contain 11 bunches instead of 12; consequently, this single bunch extraction mode will also be used for CBA injection.

  8. Design and test of the RHIC CMD10 abort kicker

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, H. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Drees, A. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Mi, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Meng, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Montag, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pai, C. [Brookhaven National Lab. (BNL), Upton, NY (United States); Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tsoupas, N. [Brookhaven National Lab. (BNL), Upton, NY (United States); Tuozzolo, J. E. [Brookhaven National Lab. (BNL), Upton, NY (United States); Zhang, W. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-05-03

    In recent RHIC operational runs, planned and unplanned pre-fire triggered beam aborts have been observed that resulted in quenches of SC main ring magnets, indicating a weakened magnet kick strength due to beam-induced ferrite heating. An improvement program was initiated to reduce the longitudinal coupling impedance with changes to the ferrite material and the eddy-current strip geometry. Results of the impedance measurements and of magnet heating tests with CMD10 ferrite up to 190°C are reported. All 10 abort kickers in the tunnel have been modified and were provided with a cooling system for the RUN 15.

  9. Operational experience with SLC damping ring kicker magnets

    International Nuclear Information System (INIS)

    The damping ring kickers for the SLAC Linear Collider must provide 7 mrad kicks to 1.2 GeV beams with 60 nsec rise and fall times and fit in a 50 cm length around a 21 mm diameter ceramic beam pipe. This requires that they operate at up to 40 KV. The construction and operation of two types of quasi-coaxial ferrite magnet potted with RTV silicone rubber is discussed. Production yield has been improved by changes in RTV degassing, transfer, and cure. Operation lifetime is dominated by voltage, radiation, and thermal cycling. 4 refs., 2 figs

  10. Operational experience with SLC damping ring kicker magnets

    International Nuclear Information System (INIS)

    The damping ring kickers for the SLAC Linear Collider must provide 7 mrad kicks to 1.2 GeV beams with 60 nsec rise and fall times and fit in a 50 cm length around a 21 mm diameter ceramic beam pipe. This requires that they operate at up to 40 KV. The construction and operation of two types of quasi-coaxial ferrite magnet potted with RTV silicone rubber is discussed. Production yield has been improved by changes in RTV degassing, transfer, and cure. Operation lifetime is dominated by voltage, radiation, and thermal cycling

  11. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Haitao, E-mail: ren@frib.msu.edu; Pozdeyev, Eduard; Lund, Steven M.; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn [Facility for Rare Isotope Beams, Michigan State University, East Lansing, Michigan 48824 (United States)

    2016-02-15

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper.

  12. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB

    Science.gov (United States)

    Ren, Haitao; Pozdeyev, Eduard; Lund, Steven M.; Machicoane, Guillaume; Wu, Xiaoyu; Morgan, Glenn

    2016-02-01

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper.

  13. Beam simulation studies of ECR beam extraction and low energy beam transport for FRIB

    International Nuclear Information System (INIS)

    To meet the beam power requirements of 400 kW at the fragmentation target for facility for Rare Isotope Beams (FRIB), simultaneous acceleration of two-charge states should be used for heavier ions. These intense multi-charged ion beams will be produced by a 28 GHz electron cyclotron resonance (ECR) ion source at a high voltage of 35 kV. After extraction, the ion beam will be pre-accelerated to 12 keV/u with a 50 kV platform, transported down to an achromatic charge state selection (CSS) system followed by a vertical transport line, and then injected into a radio frequency quadrupole accelerator. The TRACK code developed at ANL is used to perform the simulations of the ECR beam extraction and low energy beam transport for FRIB. In this study, we include the magnetic field of ECR ion source into simulations. Different initial beam conditions as well as different space charge neutralization levels are tested for the ECR beamline. The beam loss in CSS system and the corresponding protective measures are discussed. The detailed results about the beam dynamic simulation and beam loss in CSS system will be presented in this paper

  14. Beam extraction system in AIC-144 automatic isochronous cyclotron

    International Nuclear Information System (INIS)

    Project of beam extraction system in Cracow AIC-144 cyclotron is described. The problems of increase of beam emittance, and change of the magnetic field in the cyclotron chamber are discussed. Expected extraction coefficient of the beam is about 0.7. (S.B.)

  15. Irradiation of beam extraction equipment of the IHEP proton synchrotron

    International Nuclear Information System (INIS)

    The influence of the beam fast extraction on the slow extraction system septum-magnets irradiation is shown. The real meanings of beam extracting efficiency from U-70 are given. The proposals on lowering the radiating loadings on the equipment are presented. 16 refs.; 5 figs

  16. Extraction and beam transfer for the SHiP facility

    CERN Document Server

    Goddard, Brennan; Borburgh, Jan; Balhan, Bruno; Le Godec, Gilles; Zerlauth, Markus; Tommasini, Davide; Kain, Verena; Cornelis, Karel; Wenninger, Jorg; Jensen, Lars; Todd, Benjamin; Bauche, Jeremie; Puccio, Bruno

    2015-01-01

    This document summarises the key feasibility issues associated with the SPS extraction and beam transfer systems required for the SHiP facility. It describes the expected performance limits of the electrostatic septa, the expected beam losses during extraction and consequences, the design of the new beamline geometry and equipment systems and the expected extracted spill structure.

  17. Preliminary Experimental Study of Ion Beam Extraction of EAST Neutral Beam Injector

    Institute of Scientific and Technical Information of China (English)

    XU Yong-Jian; HU Chun-Dong; LIU Sheng; XIE Ya-Hong; LIANG Li-Zhen; JIANG Cai-Chao

    2012-01-01

    Neutral beam injection is recognized as one of the most effective means for plasma heating.The preliminary data of ion beam extraction is obtained on the EAST neutral beam injector test-stand.Beam extraction from the ion source of EAST-NBI is verified by measuring the beam current with a Faraday cup and by analyzing the results obtained by means of water calorimetric measurement on the temperature rises of water cooling the accelerator electrodes.

  18. Design, Manufacturing and Testing of the CTF3 Tail Clipper Kicker

    CERN Document Server

    Barnes, M J; Ravida, G; Rodriguez, I; Toral, F

    2010-01-01

    The goal of the present CLIC Test Facility (CTF3) is to demonstrate the technical feasibility of specific key issues of the CLIC scheme. The extracted drive beam from the combiner ring (CR), a pulse of 35 A magnitude and 140 ns duration, is sent to the new CLic EXperimental area (CLEX). A Tail Clipper (TC) kicker is required, in the CR to CLEX transfer line, to allow the duration of the beam pulse to be adjusted: the unwanted bunches are kicked into a collimator. The TC must have a fast field rise-time, of not more than 5 ns, in order to minimize uncontrolled beam loss. Striplines are used for the TC: to establish the required fields, the applied pulse wave front must fully propagate along the striplines. To reduce the wave front propagation time, the overall length of the stripline assembly is sub-divided into 4 sections. The TC has been designed with the aid of detailed numerical modelling: the stripline cross-section and coaxial-to-stripline transitions were carefully optimized using a 3D code. The results...

  19. Some techniques to improve time structure of slow extracted beam

    International Nuclear Information System (INIS)

    In order to improve the time structure of slow extracted beam spill for the KEK 12GeV PS, the spill control system has been upgraded by adding feed forward signal to feedback signal. Further, the wake field in the RF cavity has been cancelled by the beam bunch signal to reduce the re-bunch effect during extraction period. (author)

  20. Fast extraction control system based on field programmable gate array

    International Nuclear Information System (INIS)

    In order to realize the fast extraction of beam from the HIRFL-CSR (the Heavy Ion Research Facility at Lanzhou-Cooler Storage Ring) main ring, we adopt an extraction system based on FPGA technique. The digital multiplication of clock frequency method is employed in the design of FPGA, to accurately control the charging time and discharging time of Kicker magnet during a high-frequency period. Test results show that the time accuracy of the system reaches 5 ns for beam locating and beam adjusting in the storage ring. At the high-frequency of 1.4 MHz, triggering Kicker can be realized with phase accuracy of 2.5 degree in the scale of 0 to 360 degree. (authors)

  1. New control techniques for extraction of bevalac beams

    International Nuclear Information System (INIS)

    Beams of accelerated heavy ions can now be delivered as one-second-long dc pulses with minimal fluctuations in instantaneous flux. Pulse duration can be held constant to within 1% while keeping a high non-varying extraction efficiency which minimizes pulse-to-pulse position shift in the extracted beam. In addition, differing beam intensities over several orders of magnitude can be delivered. Computer adjustment of all measurement and control devices results in linear operation over three orders of magnitude of beam intensity. Control of beam structure is accomplished by a unique combination of dual slope integrators and phase forward ''predictive'' circuits in the feedback loop

  2. Performance of the CERN SPS Fast Extraction for the CNGS Facility

    CERN Document Server

    Gaxiola, Enrique; Höfle, Wolfgang; Roncarolo, Federico; Vogel, Elmar; Vossenberg, Eugène B

    2005-01-01

    The SPS LSS4 fast extraction system will serve both the anti-clockwise ring of the LHC and the long baseline neutrino (CNGS) facility. For the latter two extractions spaced by 50 ms, each affecting half of the SPS, are foreseen. During the shutdown 2003-2004 the performance of the fast extraction kickers has been improved in order to match more closely the specifications required for the CNGS and LHC extractions. The kick rise and fall times were significantly reduced, as well as the post-pulse kick ripple. However, the latter remained outside specifications and oscillations were induced in the leading bunches of the batch remaining in the machine at the moment of the first extraction. While further improving the kicker pulse shape, the possibility of damping the beam oscillations using the transverse feedback system has been explored. Recent pulse improvements and results of beam tests are reported.

  3. Preliminary Results of Ion Beam Extraction Tests on EAST Neutral Beam Injector

    Institute of Scientific and Technical Information of China (English)

    胡纯栋

    2012-01-01

    The neutral beam injection (NBI) system is one of the most important auxiliary plasma heating and current driving methods for fusion device. A high power ion beam of 3 MW with 80 keV beam energy in 0.5 s beam duration and a long pulse ion beam of 4 s with 50 keV beam energy ion beam extraction were achieved on the EAST neutral beam injector on the teststand. The preliminary results show that the EAST-NBI system was developed successfully on schedule.

  4. Design and optimization of a longitudinal feedback kicker cavity for the HLS-II storage ring

    Science.gov (United States)

    Xu, Wei; Z. Wu, W.; He, Duo-Hui; K. Wu, Y.

    2013-03-01

    In the Hefei Light Source (HLS) storage ring, multibunch operation is used to obtain a high luminosity. Multibunch instabilities can severely limit light source performance with a variety of negative impacts, including beam loss, low injection efficiency, and overall degradation of the beam quality. Instabilities of a multibunch beam can be mitigated using certain techniques including increasing natural damping (operating at a higher energy), lowering the beam current, and increasing Landau damping. However, these methods are not adequate to stabilize a multibunch electron beam at a low energy and with a high current. In order to combat beam instabilities in the HLS storage ring, active feedback systems including a longitudinal feedback system (LFB) and a transverse feedback system (TFB) will be developed as part of the HLS upgrade project, the HLS- II storage ring project. As a key component of the longitudinal bunch-by-bunch feedback system, an LFB kicker cavity with a wide bandwidth and high shunt impedance is required. In this paper we report our work on the design of the LFB kicker cavity for the HLS- II storage ring and present the new tuning and optimization techniques developed in designing this high performance LFB kicker.

  5. High repetition rate kickers for linear colliders

    International Nuclear Information System (INIS)

    It was shown in a previous paper that kickers with a high repetition rate can be designed by combining several cavities operating in a deflecting mode. In this paper we simplify this idea by showing that such kickers can be built also with one cavity or with an assembly of coupled cavities operating at several frequencies. We also demonstrate that this concept can be used for accelerating cavities. The electrical breakdown limit for such multimode accelerating cavities will be significantly higher than conventional single-mode cavities; therefore higher acceleration gradients, e.g., for linear colliders, can be achieved. 2 refs., 4 figs

  6. Some calculations for the RHIC kicker

    International Nuclear Information System (INIS)

    This paper starts with a brief discussion of the design of the RHIC injection kicker magnets which calls for longitudinal and capacitive sections of the same order as the aperture, not much larger nor much smaller. This makes accurate analytical prediction of their behavior very difficult. In order to gain at least some qualitative insight of that behavior, the author preformed calculations which are based on the actual dimensions of the kickers but which neglect the end effects of the individual sections. The effects of the sectionalization are therefore exaggerated relative to reality in the results

  7. Upgrade of the Nuclotron extracted beam diagnostic subsystem

    International Nuclear Information System (INIS)

    The subsystem is intended for the Nuclotron extracted beam parameters measurements. Multiwire proportional chambers are used for transversal beam profiles measurements in four points of the beam transfer line. Gas amplification values are tuned by high voltage power supplies adjustments. The extracted beam intensity is measured by means of ionization chamber, variable gain current amplifier DDPCA-300 and voltage-to-frequency converter. The data is processed by industrial PC with National Instruments DAQ modules. The client-server distributed application written in LabView environment allows operators to control hardware and obtain measurement results over TCP/IP network. (authors)

  8. BEAM TRANSFER LINES FOR THE SPALLATION NEUTRON SOURCE.

    Energy Technology Data Exchange (ETDEWEB)

    RAPARIA,D.; LEE,Y.Y.; WENG,W.T.; WEI,J.

    2002-04-08

    Beam transfer lines for the Spallation Neutron Source (SNS) are designed to have low beam losses for hand on maintenance while satisfying the facility footprint requirements. There are two main beam transfer lines, High Energy Beam Transport (HEBT) line which connect super conducting linac to the accumulator ring and Ring to Target Beam transport (RTBT) which transfers beam from accumulator ring to the target. HEBT line not only transfer the beam from linac to ring but also prepare beam for ring injection, correct the energy jitter from the linac, provide required energy spread for the ring injection, clean the transverse and longitudinal halo particles from the beam, determine the linac beam quality, and provide the protection to the accumulator ring. RTBT line transport the beam from ring to target while fulfilling the target requirements of beam size, maximum current density, beam moment on the target in case of ring extraction kicker failure. and protect the target from the ring fault conditions.

  9. Simulation of ion beam injection and extraction in an EBIS

    International Nuclear Information System (INIS)

    An example simulation of Au+ charge breeding using FAR-TECH’s integrated EBIS (electron beam ion source) modeling toolset is presented with the emphasis on ion beam injection and extraction. The trajectories of injected ions are calculated with PBGUNS (particle beam gun simulation) self-consistently by including the space charges from both ions and electrons. The ion beam, starting with initial conditions within the 100% acceptance of the electron beam, is then tracked by EBIS-PIC (particle-in-cell EBIS simulation code). In the trap, the evolution of the ion charge state distribution is estimated by charge state estimator. The extraction of charge bred ions is simulated with PBGUNS. The simulations of the ion injections show significant ion space charge effects on beam capture efficiency and the ionization efficiency

  10. Simulation of ion beam injection and extraction in an EBIS

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L., E-mail: zhao@far-tech.com; Kim, J. S. [FAR-TECH, Inc., San Diego, California 92121 (United States)

    2016-02-15

    An example simulation of Au+ charge breeding using FAR-TECH’s integrated EBIS (electron beam ion source) modeling toolset is presented with the emphasis on ion beam injection and extraction. The trajectories of injected ions are calculated with PBGUNS (particle beam gun simulation) self-consistently by including the space charges from both ions and electrons. The ion beam, starting with initial conditions within the 100% acceptance of the electron beam, is then tracked by EBIS-PIC (particle-in-cell EBIS simulation code). In the trap, the evolution of the ion charge state distribution is estimated by charge state estimator. The extraction of charge bred ions is simulated with PBGUNS. The simulations of the ion injections show significant ion space charge effects on beam capture efficiency and the ionization efficiency.

  11. Simulation of ion beam injection and extraction in an EBIS

    Science.gov (United States)

    Zhao, L.; Kim, J. S.

    2016-02-01

    An example simulation of Au+ charge breeding using FAR-TECH's integrated EBIS (electron beam ion source) modeling toolset is presented with the emphasis on ion beam injection and extraction. The trajectories of injected ions are calculated with PBGUNS (particle beam gun simulation) self-consistently by including the space charges from both ions and electrons. The ion beam, starting with initial conditions within the 100% acceptance of the electron beam, is then tracked by EBIS-PIC (particle-in-cell EBIS simulation code). In the trap, the evolution of the ion charge state distribution is estimated by charge state estimator. The extraction of charge bred ions is simulated with PBGUNS. The simulations of the ion injections show significant ion space charge effects on beam capture efficiency and the ionization efficiency.

  12. Collimator for the SPS extracted beam

    CERN Multimedia

    1976-01-01

    This is a water cooled copper collimator (TCSA) which has exactly the shape of the cross section of the downstream magnetic beam splitter. Parts of the blown up primary proton beam pass above/below and left through this collimator. A small part of the protons is absorbed in the thin copper wedges. In this way the downstream magnetic splitter of the same cross section receives already a beam where its magnetic wedges are no longer hit by protons. The upstream, water cooled collimator, more resistant to protons, has cast a 'shadow' onto the downstream magnetic splitter, less resistant to protons. Gualtero Del Torre stands on the left.

  13. Simulation of ion beam extraction and focusing system

    Institute of Scientific and Technical Information of China (English)

    B. A. Soliman; M. M. Abdelrahman; A. G. Helal; F. W. Abdelsalam

    2011-01-01

    The characteristics of ion beam extraction and focused to a volume as small as possible were investigated with the aid of computer code SIMION 3D version 7. This has been used to evaluate the extraction characteristics (accel-decel system) to generate an

  14. Beam dynamics requirement for proposed booster extraction septum magnet

    International Nuclear Information System (INIS)

    To improve the performance of Indus-2 storage ring, it is planned to operate the booster injector at beam energy of 700 MeV, which is presently being operated at 550 MeV. At higher beam energy the beam size will increase and quality of extracted beam from booster will be deteriorated because of the poor magnetic field homogeneity of existing septum magnet. As a consequence it may reduce the injection efficiency of Indus-2. In this perspective, magnetic field homogeneity and good field region of the extraction septum magnet plays a vital role. Thus it is required to upgrade the technical specification of the booster extraction septum magnet. The same has been evolved and its results are presented. (author)

  15. Transmission line analysis of dielectric-loaded ferrite kicker

    International Nuclear Information System (INIS)

    The RHIC injection kicker is constructed as a C-shaped ferrite kicker in which the ferrite blocks are spaced apart and the interstice is filled with high-permittivity dielectric. The electric properties of the kicker, such as characteristic impedance and propagation velocity, are usually analyzed as a low pass filter with lumped L and C elements. In the present paper, the kicker will be considered a transmission line with anisotropic medium in order to correctly describe the layered ferrite/dielectric structure. This treatment is valid at low frequencies where the wavelength is much larger than a ferrite/dielectric cell length. The analytical results are compared with measurements on a kicker model, thereby confirming that, in practice, the anisotropic approximation in the long-wavelength limit represents an adequate kicker description

  16. Cooling of the LHC Injection Kicker Magnet Ferrite Yoke: Measurements and Future Proposals

    CERN Document Server

    Sobiech, Z; Bouleghlimat, S; Ducimetière, L; Garlaschè, M; Kramer, T; Namora, V; Noulibos, R; Sillanoli, Y; Weterings, W

    2014-01-01

    LHC operation with high intensity beam, stable for many hours, resulted in significant heating of the ferrite yoke of the LHC Injection Kicker Magnets. For one kicker magnet the ferrite yoke approached its Curie temperature. As a result of a long thermal time-constant the yoke can require several hours to cool sufficiently to allow re-injection of beam, thus limiting the running efficiency of the LHC. The beam screen, which screens the ferrite yoke from wakefields, has been upgraded to limit ferrite heating. In addition it is important to improve the cooling of the ferrite yoke: one method is to increase the internal emissivity of the cylindrical vacuum tank, in which the kicker magnet is installed. This paper describes a method developed for measuring the emissivity of the inside of the tanks, which has been benchmarked against measurements of the ferrite yoke temperature during heat treatment in an oven and transient thermal simulations. Conclusions are drawn regarding an ion bombardment technique evaluated...

  17. Kicker pulsers for recycler NOVA upgrades

    CERN Document Server

    Jensen, Chris C

    2015-01-01

    An upgrade of the Recycler injection kicker system required a faster rise time pulser. This system required a field rise and fall time of < 57 ns and a field flattop of 1.6 {\\mu}s. This paper describes the variety of improvements made over the years that have resulted in this latest thyratron pulser. The effects of the trigger, the reservoir and the load impedance on delay and rise time will be discussed.

  18. Design, test, and operation of new tapered stripline injection kickers for the e+e- collider DAΦNE

    Science.gov (United States)

    Alesini, David; Guiducci, Susanna; Marcellini, Fabio; Raimondi, Pantaleo

    2010-11-01

    For the injection upgrade of the Φ factory DAΦNE, new fast stripline kickers have been designed. They can operate with very short pulse generators to perturb only the injected bunch and the two stored adjacent ones. The design is based on tapering the striplines to simultaneously obtain low beam coupling and transfer impedances, excellent uniformity of the deflecting field, and better matching between the strip and the pulse generators. It has been done using 2D and 3D electromagnetic codes (Superfish and HFSS). The kickers have been constructed, tested, and installed in the collider. Measurements of the reflection coefficient at input ports and of the longitudinal and transverse beam coupling impedance have been also performed to characterize the structure and have been compared to the simulation results. A circuital model of general tapered striplines for a first order estimation of the transfer and longitudinal beam coupling impedances is also presented. Finally operational performances are described, pointing out the problems which occurred and the flexibility of the stripline structures that worked with both the short and with the previously installed long pulse generators and have been used as an additional damping kicker to improve the efficiency of the horizontal multibunch feedback system. This system is also a demonstration of the operation of fast kickers with similar characteristics as those for the International Linear Collider (ILC) damping rings (DRs).

  19. Test~of~Beam~Extraction~by~Crystal~Channeling~at~the~SPS: A First Step towards a LHC Extracted Beam

    CERN Multimedia

    2002-01-01

    % RD22 \\\\ \\\\ The availability of a beam extracted out of the LHC accelerator would open up very interesting possibilities for B-physics, in particular for the study of CP-violation. Channeling in bent crystals appears to be the most promising method to produce an extracted beam of intensity $\\sim$~10$^{8}$ p/sec. This would provide as many as 10$^{10}$ $ B \\bar{B} $ pairs per year of run, two orders of magnitude more than could be produced by an e$^+$e$^-$ B-factory with L~=~10$^{34}$ cm$^{-2}$s$^{-1}$ We propose a R\\&D program to study beam extraction at the CERN SPS, using a silicon bent crystal to be installed in the SPS beam pipe and placed next to the beam in such a way as to intercept the beam halo. Transverse excitation of the beam in presence of non-linearities will be used to create halo conditions similar to what are expected for LHC.

  20. Design of the injection kicker magnet system for CERN's 14 TeV proton collider LHC

    International Nuclear Information System (INIS)

    Two counter-rotating proton beams will be injected into LHC at an energy of 450 GeV by two kicker magnet systems, producting magnetic field pulses of approximately 750 ns rise time and 6.6 μs flat top duration. To avoid dilution of the beam emittance during injection, a stringent design requirement of the system is a flat top ripple of the magnetic field of less than ±0.5%. Both injection systems are composed of 4 travelling wave kicker magnets of 2.17 m length each, powered by pulse forming networks (PFN's) and matched to their characteristic impedance. To achieve the high required kick strength of 1.2 Tm, for a compact and cost efficient design, a comparably low characteristic impedance of 5 Ω has been chosen. The electrical circuit of the system is being designed with the help of PSpice computer modelling. Most known parasite elements are included in the model to obtain a realistic pulse response prediction. The present paper reports on design and modeling results of the LHC injection kicker magnet system that has several novel and demanding design requirements. (author)

  1. Design of the injection kicker magnet system for CERN's 14 TeV proton collider LHC

    International Nuclear Information System (INIS)

    Two counter-rotating proton beams will be injected into the LHC at an energy of 450 GeV by two kicker magnet systems, producing magnetic field pulses of approximately 750 ns rise time and 6.6 micros flat top duration. To avoid dilution of the beam emittance during injection, a stringent design requirement of the system is a flat top ripple of the magnetic field of less than ±0.5%. Both injection systems are composed of 4 travelling wave kicker magnets of 2.17 m length each, powered by pulse forming networks (PFN's) and matched to their characteristic impedance. To achieve the high required kick strength of 1.2 Tm, for a compact and cost efficient design, a comparably low characteristic impedance of 5 Ω has been chosen. The electrical circuit of the system is being designed with the help of PSpice computer modeling. Most known parasitic elements are included in the model to obtain a realistic pulse response prediction. The present paper reports on design and modeling results of the LHC injection kicker magnet system that has several novel and demanding design requirements

  2. Induced radioactivity of the IHEP proton synchrotron beam extraction equipment

    International Nuclear Information System (INIS)

    The measurement results of induced radioactivity of the beam extraction equipment during 1972-1978 are presented. All the values are given to the moment of the accelerator stop. The experimental data permits to predict further possible variations of the induced radioactivity levels of the equipment. Given are the measures required for reduction of the accelerator equipment irradiation, which are the following: 1) compensation of residual distortion of a closed beam orbit in the course of the induction system operation; 2) limitation of the intensity of drop on the internal targets up to the 11 protons per target level over a cycle; 3) putting into operation the program control system for the duration of a current pulse of a linear accelerator to minimize the beam residues at the 70 GeV energy during physical experiments; 4) construction of the system of beam interception and cutting-off to ensure effective energy suppression of uncontrolled beam residues and localization of their radiation effect; 5) extraction of a high-energy beam out of the accelerator during the experiments (e.g., into the neutrino channel for apparatus adjusting) instead of its dropping on the interceptor-target; 6) beam orbit controlling in the case of multiturn injection into the accelerator

  3. Emittance Measurements for Beams Extracted from LECR3 Ion Source

    Institute of Scientific and Technical Information of China (English)

    CaoYun; ZhaoHongwei; MaLei; ZhangZimin

    2003-01-01

    High quality ion beams are required by IMP cyclotron and atomic physics research, so it is important to research and measure beam emitt ance of ECR ion source. Intense beams extracted from ECR ion source usually have low energy, so it is suitable to use Electric-Sweep Scanner to measure the emittance. This kind of measurement is popularly used at ECR ion source, and it has some prominent merits such as high accuracy, very short time of data processing and easy expressing of the emittance pattern. So we designed and built this emittance scanner to measure emittance of the ion beams produced by LECR3 ion source. The structure of the ESS is shown in Fig.l, and the photo of the ESS is shown in Fig.2.

  4. Design and development of modified injection kicker power supply for booster synchrotron

    International Nuclear Information System (INIS)

    Booster Synchrotron of Indus at RRCAT Indore is proposed to be modified for higher energy (30 MeV Linac) injection. The injection kicker specifications were modified accordingly. The present injection kicker generates a half sine type current pulse of 800 A with 13 μs pulse width. The proposed injection kicker power supply, required to cater to new requirement, is to deliver a half sine type current pulse of 2000 A with μs pulse width. Injection will take place in last 500 ns of this pulse. Critical design feature of such pulse is linearly falling current with low undershoot. For such a high current and small pulse width, it was difficult to meet this critical technical requirement of this pulse because of technically challenging demand on switching device. Knowing the fact that beam is injected during the last 500 ns, a pulse with 4.5 μs sinusoidal rise and 500 ns linear fall is proposed. This modification changes the requirement of peak current to approximately 700 A. This 700 A pulse has been generated using a fast controlled switch to meet required specifications. The operational features and challenges faced are discussed. Taking advantage of microsecond pulse width with low repetition rate (1 Hz), this power supply uses an IGBT switch operating beyond its specified peak current. (author)

  5. LHC Beam Dump System: Analysis of beam commissioning, performance and the consequences of abnormal operation

    CERN Document Server

    Kramer, Thomas

    2011-01-01

    The LHC accelerates proton beams to a momentum of up to 7 TeV/c. At this energy level and with nominal beam intensity the stored energy of 360 MJ per beam is sufficient to melt 500 kg of copper. In addition up to 10 GJ are stored within the LHC magnet system at top energy. It is obvious that such a machine needs well designed safety and protection systems. The LHC Beam Dump System (LBDS) is such a system and one of the most critical once concerning machine protection and safe operation. It is used to dispose of high intensity beams between 450 GeV and 7 TeV and is thus designed to fast extract beam in a loss free way and to transfer it to an external absorber. For each ring systems of 15 horizontal fast kicker magnets (MKD), 15 vertically deflecting magnetic septa (MSD) and 10 diluter kicker magnets (MKB) are installed. This thesis is concerned with the analysis of the LBDS performance under normal operating parameters as well as under abnormal conditions like in the event of asynchronous beam abort or missin...

  6. Extracting source parameters from beam monitors on a chopper spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Abernathy, Douglas L [ORNL; Niedziela, Jennifer L [ORNL; Stone, Matthew B [ORNL

    2015-01-01

    The intensity distributions of beam monitors in direct-geometry time-of-flight neutron spectrometers provide important information about the instrument resolution. For short-pulse spallation neutron sources in particular, the asymmetry of the source pulse may be extracted and compared to Monte Carlo source simulations. An explicit formula using a Gaussian-convolved Ikeda-Carpenter distribution is given and compared to data from the ARCS instrument at the Spallation Neutron Source.

  7. Proposal for Efficiency Improvement of Beam Extraction from the AIC-l44 Beam Formation During Its Acceleration

    International Nuclear Information System (INIS)

    The computer simulations of the beam dynamics both in the radial and vertical phase planes for the AIC-144 cyclotron are presented. The calculation results show how it is possible to improve the beam extraction efficiency

  8. Behavior of Negative Hydrogen Ion and its Beam by Bias and Beam Extraction Voltages

    Science.gov (United States)

    Nakano, Haruhisa; Tsumori, Katsuyoshi; Kisaki, Masashi; Ikeda, Katsunori; Geng, Shaofei; Nagaoka, Kenichi; Osakabe, Masaki; Takeiri, Yasuhiko; Kaneko, Osamu; Serianni, Gianluigi; Agostinetti, Piero; Sartori, Emanuele; Brombin, Matteo; Wimmer, Christian

    2015-09-01

    Negative hydrogen ion (H-) dynamics from production to beam extraction in H- source for fusion have not been enough understood in cesium-seeded negative-hydrogen-ion sources. This dynamics understanding contributes constructions of higher performance ion sources. The H- is produced on and emitted from plasma grid electrode (PG) which is boundary electrode between source plasma and beam. The H- density in the vicinity of the PG decreased with bias voltage (between PG and arc chamber) by suppression of H- emission and/or yield. The H- density decrement was observed in H- beam extraction phase and penetrated to 30 mm depth from PG. The depth and H- beam current decreased with bias voltage. One of the possibilities which explain it is extracted H- coming from space in the vicinity of the PG. An object made of ceramic was inserted above the PG aperture. The H- beam intensity decreased if the object was set 9 mm from PG. This does not conflict with the possibility. This work is supported by NIFS Research Programs NIFS13ULRR008 and NIFS13ULRR702, and JSPS KAKENHI Grant Numbers 25800307 and 25249134.

  9. Fooling the kickers but not the goalkeepers: behavioral and neurophysiological correlates of fake action detection in soccer.

    Science.gov (United States)

    Tomeo, Enzo; Cesari, Paola; Aglioti, Salvatore M; Urgesi, Cosimo

    2013-11-01

    Studies demonstrate that elite athletes are able to extract kinematic information of observed domain-specific actions to predict their future course. Little is known, however, on the perceptuo-motor processes and neural correlates of the athletes' ability to predict fooling actions. Combining psychophysics and transcranial magnetic stimulation, we explored the impact of motor and perceptual expertise on the ability to predict the fate of observed actual or fake soccer penalty kicks. We manipulated the congruence between the model's body kinematics and the subsequent ball trajectory and investigated the prediction performance and cortico-spinal reactivity of expert kickers, goalkeepers, and novices. Kickers and goalkeepers outperformed novices by anticipating the actual kick direction from the model's initial body movements. However, kickers were more often fooled than goalkeepers and novices in cases of incongruent actions. Congruent and incongruent actions engendered a comparable facilitation of kickers' lower limb motor representation, but their neurophysiological response was correlated with their greater susceptibility to be fooled. Moreover, when compared with actual actions, motor facilitation for incongruent actions was lower among goalkeepers and higher among novices. Thus, responding to fooling actions requires updation of simulative motor representations of others' actions and is facilitated by visual rather than by motor expertise. PMID:22941722

  10. Microcontroller based two axis microtron beam extraction system

    International Nuclear Information System (INIS)

    Microtron is an electron accelerator which is used to accelerate the electron beam. The Microtron consists of electro magnet with two poles separated by yoke for completion of path for magnetic flux lines. A compact Microtron capable of accelerating electrons up to 12 MeV has been developed in RRCAT. The beam from the Microtron has to be extracted from various orbits depending upon the user requirement (X-Y stage is built with an accuracy of 100 μm). This paper describes the design and development of microcontroller based two axis beam extraction system for Microtron, with a resolution of 50 μm to position the extraction tube with respect to selected orbit. Two axis motion controller is developed using current controlled micro-stepping driver mechanism, which uses Bipolar Chopper Drive for driving stepper motors. Each phase has 2A continuous driving capability. The system is provided with user selectable controls like speed, steps, direction, and mode. This system is provided with RS-232 interface, to accept commands from PC. This system also has local keyboard and LCD interface to use in Stand-alone mode (local Mode). (author)

  11. Conceptual Design Considerations for the 50 TeV FCC Beam Dump Insertion

    CERN Document Server

    Burkart, Florian; Barna, Daniel; Bartmann, Wolfgang; Goddard, Brennan; Kramer, Thomas; Lechner, Anton; Sanz Ull, Alejandro; Schulte, Daniel; Stoel, Linda

    2016-01-01

    Safely extracting and absorbing the 50 TeV proton beams of the FCC-hh collider will be a major challenge. Two extended straight sections (ESS) are dedicated to beam dumping system and collimation. The beam dumping system will fast-extract the beam and transport it to an external absorber, while the collimation system will protect the superconducting accelerator components installed further downstream. The high stored beam energy of about 8.5 GJ per beam means that machine protection considerations will severely constrain the functional design of the ESS and the beam dump line geometry, in addition to dominating the performance specifications of the main sub-systems like kickers and absorber blocks. The general features, including concept choice, optics in the ESS and beam dump line, passive protection devices, layout and integration are described and discussed.

  12. Design of the ILC Prototype FONT4 Digital Intra-Train Beam-Based Feedback System

    International Nuclear Information System (INIS)

    We present the design of the FONT4 digital intra-train beam position feedback system prototype and preliminary results of initial beam tests at the Accelerator Test Facility (ATF) at KEK. The feedback system incorporates a fast analogue beam position monitor (BPM) front-end signal processor, a digital feedback board, and a kicker driver amplifier. The short bunchtrain, comprising 3 electron bunches separated by c. 150ns, in the ATF extraction line was used to test components of the prototype feedback system

  13. Slot-type pickup/kicker for AA stochastic cooling

    CERN Multimedia

    1979-01-01

    A "slotted transmission line" was used for both pickups and kickers of the stochastic cooling systems of the AA. They served for the cooling of the high-density antiproton stack, in momentum and both transverse planes. In the beginning, in a single band, 1-2 GHz, later in 2 bands, 2-4 and 4-8 GHz. View down the centre of a pickup or kicker. See also 7906189, 7906190, 7906583.

  14. The new control system of the SPS injection kicker

    CERN Document Server

    Antoine, A; Marchand, A; Verhagen, H

    2002-01-01

    The SPS accelerator will be used as injector for the LHC and has to be adapted to the LHC requirements. The tight specification on beam blow-up and bunch spacing in the SPS has required an upgrade program of the SPS injection kicker in order to obtain a reduction of the magnetic field ripple to less than ± 0.5% and of the magnet current rise time to less than 145 ns. In this context, the slow control part has been entirely rebuilt on the basis of off-the-shelf industrial components. A hierarchical architecture based on a SIEMENS S7-400 master programmable logic controller interconnected through PROFIBUS-DP to S7-300 deported and decentralised I/Os has been implemented. Integration of in-house specific G-64 hardware systems inside this industrial environment has been done through a PROFIBUS-DP to G-64 intelligent interface based on an OEM fieldbus mezzanine board on one side and an FPGA implementing the required functionality on the other. Simultaneously, the fast timing system has been completely reshuffled ...

  15. Beam injection into RHIC

    International Nuclear Information System (INIS)

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. The authors describe the injection zone and its bottlenecks. They report on the commissioning of the injection system, on beam based measurements of the kickers and the application program to steer the beam

  16. Measurements of an ion beam diameter extracted into air through a glass capillary

    International Nuclear Information System (INIS)

    To establish techniques for in-air materials analysis using a glass capillary, we studied the beam distribution extracted in air as a function of the distance between the exit of the capillary and the target. We measured three-dimensional intensity distributions of the extracted beams, and compared the observed results with the model calculation. The comparison showed that the glass capillary technique is designed to reduce a divergence of the beam extracted into the air by a beam-focusing effect

  17. Extracting respiratory signals from thoracic cone beam CT projections

    CERN Document Server

    Yan, Hao; Yin, Wotao; Pan, Tinsu; Ahmad, Moiz; Mou, Xuanqin; Cervino, Laura; Jia, Xun; Jiang, Steve B

    2012-01-01

    Patient respiratory signal associated with the cone beam CT (CBCT) projections is important for lung cancer radiotherapy. In contrast to monitoring an external surrogate of respiration, such signal can be extracted directly from the CBCT projections. In this paper, we propose a novel local principle component analysis (LPCA) method to extract the respiratory signal by distinguishing the respiration motion-induced content change from the gantry rotation-induced content change in the CBCT projections. The LPCA method is evaluated by comparing with three state-of-the-art projection-based methods, namely, the Amsterdam Shroud (AS) method, the intensity analysis (IA) method, and the Fourier-transform based phase analysis (FT-p) method. The clinical CBCT projection data of eight patients, acquired under various clinical scenarios, were used to investigate the performance of each method. We found that the proposed LPCA method has demonstrated the best overall performance for cases tested and thus is a promising tech...

  18. Design of a stripline kicker for tune measurement in CSNS RCS

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-Yu; XU Tao-Guang; FU Shi-Nian; LIU Yu-Dong; LI Yong; ZHAO Ya-Liang

    2012-01-01

    For CSNS RCS tune measurement,tune value is measured by exciting the bunch with a strip-line kicker fed with white noise and using a FFT algorithm.This article simulates the strip-line kicker in RCS and the efficiency of the kicker is discussed in a Matlab environment.The parameters of the kicker with an arc electrode structure such as a VSWR,wake impedance,and thermal state are analyzed based on the advantages of this design.

  19. Using multiple pickups for transverse feedback systems and optimal pickups–kicker placement for noise power minimization

    International Nuclear Information System (INIS)

    We propose a new concept to use multiple pickups for estimating the beam displacement at the position 90° before the kicker is activated. The estimated values should be the driving feedback signal. The signals from the different pickups are delayed such that they correspond to the same bunch. Subsequently, a weighted sum of the delayed signals is suggested as an estimator of the feedback correction signal. The weighting coefficients are calculated in order to achieve an unbiased estimator, i.e., the output corresponds to the actual beam displacement at the position 90° before the kicker for non-noisy pickup signals. Furthermore, the estimator must provide the minimal noise power at the output among all linear unbiased estimators. This proposed concept is applied in our new approach to find optimal places for the pickups and the kicker around the accelerator ring such that the noise effect on the feedback quality is minimized. Finally, simulation results for the heavy ions synchrotrons SIS 18 at the GSI are shown

  20. Experimental optimization of beam quality extracted from a duoplasmatron proton ion source

    Energy Technology Data Exchange (ETDEWEB)

    Batygin, Y. K.; Draganic, I. N.; Fortgang, C. M. [LANL, Los Alamos, New Mexico 87545 (United States)

    2014-10-01

    The LANSCE accelerator facility operates with two independent ion injectors for H⁺ and H⁻ particle beams. The H⁺ ion beam is formed using a duoplasmatron source followed by a 750 keV Cockroft-Walton accelerating column. Formation of an optimal plasma meniscus is an important feature for minimizing beam emittance, and maximizing beam brightness. A series of experiments were performed to find the optimal combination of extraction voltage and extracted current for the H⁺ beam. Measurements yielded the best ratio of beam perveance to Child–Langmuir perveance of 0.52 for maximizing beam brightness.

  1. Risk Assessment of the Chopper Dipole Kicker Magnets for the MedAustron Facility

    CERN Document Server

    Kramer, T; Barnes, M J; Benedikt, M; Fowler, T

    2011-01-01

    The MedAustron facility, to be built in Wiener Neustadt (Austria), will provide protons and ions for both cancer therapy and research [1]. Different types of kicker magnets will be used in the accelerator complex, including fast beam chopper dipoles: these allow the beam to be switched on and off for routine operational reasons or in case of emergency. Main requirements for the beam chopper system are safety and reliability. A criticality analysis, to chart the probability of failure modes against the severity of their consequences of the fault, has been carried out for the chopper dipole system. This "Failure Mode, Effects, and Criticality Analysis" (FMECA), has been used to highlight failure modes with relatively high probability and severity of consequences: conservative ratings of critical components and appropriate redundancy, together with measurements and interlocks, have been used to reduce the probability and criticality of faults. This paper gives an overview of the Risk Assessment approach and pres...

  2. Harmonic Resonant Kicker Design for the MEIC Electron Circular Cooler Ring

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yulu [Institute of Modern Physics, CAS, Lanzhou (China); UCAS, Beijing (China); Wang, Haipeng [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2015-09-01

    Bunched-beam electron cooling of the high-energy ion beam emittance may be a crucial technology for the proposed Medium energy Electron Ion Collider (MEIC) to achieve its design luminosity. A critical component is a fast kicker system in the Circular Ring (CR) that periodically switches electron bunches in and out of the ring from and to the driver Energy Recovery Linac (ERL). Compared to a conventional strip-line type kicker, a quarter-wave resonator (QWR)-based deflecting structure has a much higher shunt impedance and so requires much less RF power. The cavity has been designed to resonate simultaneously at many harmonic modes that are integer multiples of the fundamental mode. In this way the resulting waveform will kick only a subset of the circulating bunches. In this paper, analytical shunt impedance optimization, the electromagnetic simulations of this type of cavity, as well as tuner and coupler concept designs to produce 5 odd and 5 even harmonics of 47.63MHz will be presented, in order to kick every 10th bunch in a 476.3 MHz bunch train.

  3. Analytical and simulation studies for diode and triode ion beam extraction systems

    Institute of Scientific and Technical Information of China (English)

    M. M. Abdelrahman1; N. I. Basal; S. G. Zakhary

    2012-01-01

    This work is concerned with ion beam dynamics and compares the emittance to aberration ratios of two-and three-electrode extraction systems.The study is conducted with the aid of Version 7 of SIMION 3D ray-tracing software.The beam dependence on various parameters of the extraction systems is studied and the numerical results lead to qualitative conclusions.Ion beam characteristics using diode and triode extraction systems are investigated with the aid of the computer code SIMION 3 D,Version 7.0. The diode (two electrode extraction system) and triode (threeelectrode extraction,acceleration-deceleration system) extraction systems are designed and optimized with different geometric parameters of the electrode system,voltage applied to the extraction electrode,and plasma parameters inside the ion source chamber,as well as by the ion beam space charge.This work attempts to describe the importance of the acceleration-deceleration extraction system.It shows that besides an increase of the beam energy,the ion beam has lower emittance than the two-electrode extraction system.Ion beams of the highest quality are extracted whenever the half-angular divergence is minimum for which the perveance current intensity and the extraction gap have optimum value.Knowing the electron temperature of the plasma is necessary to determine plasma potential and the exact beam energy.

  4. The H line: a brand new beam line for fundamental physics at the J-PARC muon facility

    International Nuclear Information System (INIS)

    The muon facility, J-PARC (Muon Science Establishment; MUSE), has been operated since first beam in 2008. Starting with a 200 kW proton beam, the beam intensity has reached 3×106/ muons/s, the most intense pulsed muon beam in the world. A 2 cm thick graphite target permits the extraction of four secondary muon beams. A brand new beam line, the H line, is planned to be constructed. The new beam line is designed to have a large acceptance, will provide the ability to tune the momentum, and use a kicker magnet and/or Wien filter. This beam line will provide an intense beam for experiments that require high statistics and must occupy the experimental areas for a relatively long period.

  5. Tests of the FONT3 Linear Collider Intra-Train Beam Feedback System at the ATF

    International Nuclear Information System (INIS)

    We report preliminary results of beam tests of the FONT3 Linear Collider intra-train position feedback system prototype at the Accelerator Test Facility at KEK. The feedback system incorporates a novel beam position monitor (BPM) processor with a latency below 5 nanoseconds, and a kicker driver amplifier with similar low latency. The 56 nanosecond-long bunchtrain in the ATF extraction line was used to test the prototype BPM processor. The achieved latency will allow a demonstration of intra-train feedback on timescales relevant even for the CLIC Linear Collider design

  6. Differential pumping system for electron beam extraction in atmosphere

    International Nuclear Information System (INIS)

    The design of a differential pumping system (DPS) for extraction of an electron beam from the shaping region with a pressure of approximately 10-5 torr into the atmosphere is described. The system consists of five sections, with individual vacuum pumping. To reduce the dimensions of DPS the first three sections are pumped out through intermediate volumes connected to vapour-oil pumps. At the DPS outlet, a diaphragm with a small opening is replaced by an air ejector, which considerably improves the operation of DPS and makes it possible to increase the opening in the outlet diaphragm to 4-6 mm. The pressure in the DPS sections has been calculated, and the results are confirmed by experimental data

  7. Development of beam current control system in RF-knockout slow extraction

    Energy Technology Data Exchange (ETDEWEB)

    Mizushima, K., E-mail: mizshima@nirs.go.jp [Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan); Graduate School of Science and Technology, Chiba University, Yayoi-cho, Inage-ku, Chiba 263-8522 (Japan); Sato, S.; Shirai, T.; Furukawa, T.; Katagiri, K.; Takeshita, E.; Iwata, Y.; Himukai, T.; Noda, K. [Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba 263-8555 (Japan)

    2011-12-15

    A raster scanning method has been developed for cancer therapy at NIRS-HIMAC. This method requires a high-accuracy beam current control and fast beam-on/off switching. We have developed a feedback control system of the beam current with the RF-knockout slow extraction method. The system has allowed a stable response to beam-on/off switching using a feedback control delay function with a beam-current ripple of 7%.

  8. A Study on the Ion Beam Extraction using Duo-PiGatron Ion source for Vertical Type Ion Beam Facility

    International Nuclear Information System (INIS)

    In Korea Multipurpose Accelerator Complex (KOMAC), we have started ion beam service in the new beam utilization building since March this year. For various ion beam irradiation services, we are developed implanters such as metal (150keV/1mA), gaseous (200keV/5mA) and high current ion beam facility (20keV/150mA). One of the new one is a vertical type ion beam facility without acceleration tube (60keV/20mA) which is easy to install the sample. After the installation is complete, it is where you are studying the optimal ion beam extraction process. Detailed experimental results will be presented. Vertical Type Ion Beam Facility without acceleration tube of 60keV 20mA class was installed. We successfully extracted 60keV 20mA using Duo- PiGatron Ion source for Vertical Type Ion Beam Facility. Use the BPM and Faraday-cup, is being studied the optimum conditions of ion beam extraction

  9. A Study on the Ion Beam Extraction using Duo-PiGatron Ion source for Vertical Type Ion Beam Facility

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bom Sok; Lee, Chan young; Lee, Jae Sang [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    In Korea Multipurpose Accelerator Complex (KOMAC), we have started ion beam service in the new beam utilization building since March this year. For various ion beam irradiation services, we are developed implanters such as metal (150keV/1mA), gaseous (200keV/5mA) and high current ion beam facility (20keV/150mA). One of the new one is a vertical type ion beam facility without acceleration tube (60keV/20mA) which is easy to install the sample. After the installation is complete, it is where you are studying the optimal ion beam extraction process. Detailed experimental results will be presented. Vertical Type Ion Beam Facility without acceleration tube of 60keV 20mA class was installed. We successfully extracted 60keV 20mA using Duo- PiGatron Ion source for Vertical Type Ion Beam Facility. Use the BPM and Faraday-cup, is being studied the optimum conditions of ion beam extraction.

  10. Performance of the FONT3 Fast Analogue Intra-Train Beam-Based Feedback System at ATF

    International Nuclear Information System (INIS)

    We report results of beam tests of the FONT3 intra-train position feedback system prototype at the Accelerator Test Facility (ATF) at KEK. The feedback system incorporates a novel beam position monitor (BPM) processor with latency below 5 nanoseconds, and a kicker driver amplifier with similar low latency. The 56 nanosecond-long bunchtrain in the ATF extraction line was used to test the prototype feedback system. The achieved latency of 23ns provides a demonstration of intra-train feedback on very short timescales relevant even for the CLIC Linear Collider design

  11. Slot-type pickup/kicker for AA stochastic cooling

    CERN Multimedia

    1979-01-01

    A "slotted transmission line" was used for both pickups and kickers of the stochastic cooling systems of the AA. They served for the cooling of the high-density antiproton stack, in momentum and both transverse planes. In the beginning in a single band, 1-2 GHz, later in 2 bands, 2-4 and 4-8 GHz. See also 7906190, 7906193.

  12. One magnet module of the full-aperture kicker

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    Nine such modules, in a single vacuum tank, form the complete kicker. Ferrite rings (not visible), in conjunction with the capacitance between the plates, create the electrical equivalent of a transmission line. A fast 40 kV pulse is applied, and field rise times of 70-80 nanoseconds can be obtained.

  13. A kicker upgrade for Los Alamos proton storage ring

    International Nuclear Information System (INIS)

    Brief coverage of a kicker upgrade for the Los Alamos proton storage ring was presented under the following topic headings: specifications, current required, inductance, rise time, tricks to divide the inductance, safety considerations, accelerated lifetime tests, effect of ferrite permeability and SPICE calculations

  14. Disintegration of urinary calculi by laser beam: drilling experiment in extracted urinary stones.

    Science.gov (United States)

    Tanahashi, Y; Orikasa, S; Chiba, R; Tahira, K; Fukatsu, T; Miyakawa, T

    1979-06-01

    Disintegration of urinary calculi was attempted by the use of laser beam. As a first step, drilling of extracted urinary stones was attempted using a continuous wave CO2 laser and a pulse ruby laser. Stones were drilled easily by either laser beam. The power around 10 W of continuous CO2 laser beam was sufficient to drill through the stone. PMID:462477

  15. Estimation of thermal shocks of extraction window for SuperKEKB

    International Nuclear Information System (INIS)

    The beam-abort system is an indispensable element of SuperKEKB to protect the sensitive components of the Belle detectors and the accelerator components from possible damages caused by possible loss of intense beams. The beam current of the low energy ring at the SuperKEKB is higher than that of the KEKB by a factor of two. In order to relax the power density at the window, a vertical kicker is introduced, which vertically sweeps the beam by 10 mm on the window. When the dumped beam hit the extraction window, maximum temperature rise of the window is estimated to be about 350 degrees. This report estimates the effect of thermal shocks on extraction window. (author)

  16. Parasitic slow extraction of extremely weak beam from a high-intensity proton rapid cycling synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Ye [University of Science and Technology of China, Hefei, Anhui 230029 (China); Institute of High Energy Physics, CAS, Yuquan Road 19B, Beijing 100049 (China); Tang, Jingyu, E-mail: tangjy@ihep.ac.cn [University of Science and Technology of China, Hefei, Anhui 230029 (China); Institute of High Energy Physics, CAS, Yuquan Road 19B, Beijing 100049 (China); Yang, Zheng; Jing, Hantao [Institute of High Energy Physics, CAS, Yuquan Road 19B, Beijing 100049 (China)

    2014-02-11

    This paper proposes a novel method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron (RCS) in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction method from a synchrotron by employing third-order resonance cannot be applied in a high-intensity RCS due to a very short flat-top at the extraction energy and the strict control on beam loss. The proposed parasitic slow extraction method moves the beam to scrape a scattering foil prior to the fast beam extraction by employing either a local orbit bump or momentum deviation or their combination, so that the halo part of the beam will be scattered. A part of the scattered particles will be extracted from the RCS and guided to the experimental area. The slow extraction process can last about a few milliseconds before the beam is extracted by the fast extraction system. The method has been applied to the RCS of China Spallation Neutron Source. With 1.6 GeV in the extraction energy, 62.5 μA in the average current and 25 Hz in the repetition rate for the RCS, the proton intensity by the slow extraction method can be up to 2×10{sup 4} protons per cycle or 5×10{sup 5} protons per second. The extracted beam has also a good time structure of approximately uniform in a spill which is required for many applications such as detector tests. Detailed studies including the scattering effect in the foil, the local orbit bump by the bump magnets and dispersive orbit bump by modifying the RF pattern, the multi-particle simulations by ORBIT and TURTLE codes, and some technical features for the extraction magnets are presented.

  17. Monitoring the extracted proton beam at the SPS

    CERN Multimedia

    1977-01-01

    Fluorescent screens in front of the target positions allow a precise adjustement in front of them. A similar photo was recorded at the beam dump at the beam injection into the SPS, see Weekly Bulletin of April 1976.

  18. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    Energy Technology Data Exchange (ETDEWEB)

    Carrigan, R.A. Jr.

    1996-10-01

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed.

  19. Straw man 900-1000 GeV crystal extraction test beam for Fermilab collider operation

    International Nuclear Information System (INIS)

    A design for a 900-1000 GeV, 100 khz parasitic test beam for use during collider operations has been developed. The beam makes use of two bent crystals, one for extraction and the other one for redirecting the beam in to the present Switchyard beam system. The beam requires only a few modifications in the A0 area and largely uses existing devices. It should be straight-forward to modify one or two beam lines in the fixed target experimental areas to work above 800 GeV. Possibilities for improvements to the design,to operate at higher fluxes are discussed

  20. MARS Tracking Simulations for the Mu2e Slow Extracted Proton Beam

    Energy Technology Data Exchange (ETDEWEB)

    Nagaslaev, Vladimir [Fermilab; Rakhno, Igor [Fermilab

    2015-06-01

    Particle tracking taking into account interactions with fields and materials is necessary for proper evaluation of the resonant extraction losses and geometry optimization for the extraction beam line. This paper describes the tracking simulations for the Mu2e Resonant Extraction and discusses the geometry choices made based on these simulations.

  1. Ion beam extraction from a matrix ECR plasma source by discrete ion-focusing effect

    DEFF Research Database (Denmark)

    Stamate, Eugen; Draghici, Mihai

    2010-01-01

    Positive or negative ion beams extracted from plasma are used in a large variety of surface functionalization techniques such as implantation, etching, surface activation, passivation or oxidation. Of particular importance is the surface treatment of materials sensitive to direct plasma exposure...... due to high heath fluxes, the controllability of the ion incidence angle, and charge accumulation when treating insulating materials. Despite of a large variety of plasma sources available for ion beam extraction, there is a clear need for new extraction mechanisms that can make available ion beams...... with high current densities that can treat surfaces placed adjacent to the extraction region. This work introduces a new phenomenology for ion beam extraction using the discrete ion-focusing effect associated with three-dimensional plasma-sheath-lenses [1, 2]. Experiments are performed in a matrix...

  2. Extraction characteristics of a low-energy ion beam system with a remote plasma chamber

    International Nuclear Information System (INIS)

    Low-energy argon beams were extracted from a dual-chamber ion source system. The first chamber is a quartz cylinder where dense inductively coupled plasmas were produced using 13.56 MHz radio frequency (rf) power. The discharge was driven into an adjacent chamber which acts as a reservoir for ion beam extraction using a dual-electrode extractor configuration. Extraction of ions from the second chamber with energies in the 100 eV range was achieved while minimizing fluctuations induced by the rf signal. A custom-built retarding potential analyzer was used to analyze the effectiveness of ion beam transport using the remote plasma chamber. Well-defined beams were extracted between 60 and 100 V extraction potentials at 50–100 W rf powers. An increase in rf power resulted in an increase in average ion energy, increase in ion current density while the energy spread remains constant

  3. Extraction characteristics of a low-energy ion beam system with a remote plasma chamber

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez, M. R., E-mail: mrvasquez@coe.upd.edu.ph [Department of Mining, Metallurgical, and Materials Engineering, College of Engineering, University of the Philippines, Diliman, Quezon City 1101 (Philippines); Wada, M. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan)

    2016-02-15

    Low-energy argon beams were extracted from a dual-chamber ion source system. The first chamber is a quartz cylinder where dense inductively coupled plasmas were produced using 13.56 MHz radio frequency (rf) power. The discharge was driven into an adjacent chamber which acts as a reservoir for ion beam extraction using a dual-electrode extractor configuration. Extraction of ions from the second chamber with energies in the 100 eV range was achieved while minimizing fluctuations induced by the rf signal. A custom-built retarding potential analyzer was used to analyze the effectiveness of ion beam transport using the remote plasma chamber. Well-defined beams were extracted between 60 and 100 V extraction potentials at 50–100 W rf powers. An increase in rf power resulted in an increase in average ion energy, increase in ion current density while the energy spread remains constant.

  4. A feasibility study of H{sup -} beam extraction technique using YAG laser

    Energy Technology Data Exchange (ETDEWEB)

    Meigo, Shin-ichiro; Hasegawa, Kazuo; Ikeda, Yujiro; Oigawa, Hiroyuki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Aoki, Nobutada [Toshiba Power System Co., Ltd. (Japan); Nakagawa, Satoshi [Toshiba Co., Tokyo (Japan)

    2002-12-01

    Under a framework of JAERI-KEK joint project of high intensity proton accelerator, as for research and develop of the accelerator driven nuclear transmutation of the long lived radioactive nuclide, it is planed to built the Transmutation Physics Experiment Facility (TEF-P) and the Transmutation Engineering Experiment Facility (TEF-E). The TEF-P is used for the experiments for subcritical system coupled with a spallation neutron target bombarded with 600-MeV proton beam accelerated by the LINAC. To limit the maximum thermal power less than 500 W at the TEF-P, an incident beam power should be less than 10 W. On the contrary, at the TEF-E, high power beam of 200 kW is requested. Both high and low power beams are demanded for the transmutation facilities. It is difficult to deliver a low power beam to the TEF-P. Conventional beam extraction technique with a thin foil, is not desirable because the scattering of the beam at the foil requires the massive shield. Therefore, we study a new technique to extract a small portion of the beam precisely from the high intensity beam by using a laser beam. By a laser beam, H{sup -} in the beam from LINAC is partially changed to H{sup 0} beam so that a low current H{sup 0} beam can be obtained. As the cross section of the charge exchange reaction for H{sup -} ions has a peak around at a wave length of 1 {mu}m for photons, YAG laser is suitable for this charge exchange because of its 1.06 {mu}m wave length. It is derived that 10 W beam for 600-MeV proton can be extracted by the YAG laser with power of 2 J for each pulse of 25 Hz. By this technique, the pulse width for the extracted beam can be controlled by changing the time width of laser irradiation. When a charge exchanger having the beam collide point existing in straight section, a background beam current of projectile, however, will be increased due to the interaction with the residual gas in the beam duct. Thus, a charge exchanger is devised having the beam collide point in a

  5. Bucket-by-bucket on-axis/off-axis injection by fast kicker with variable position dependence of kick

    International Nuclear Information System (INIS)

    The bucket-by-bucket on-axis/off-axis injection system is proposed with new stripline fast kicker with variable position dependence of kick, from dipole to quadrupole, controlled by the drive voltage and its polarity. Applying the injection system to on-axis injection necessary for ultimate storage rings with narrow dynamic aperture, every bucket can be stored to achieve high average current with top-up operation. Also the minimum perturbation for stored beam can be achieved with the system by limiting the perturbations to injected bucket. Also the impurity electrons are prevented from injection with this system. (author)

  6. Fast calculation of the resistive wall wake sum for multi bunch beams

    CERN Document Server

    Vogel, E

    2005-01-01

    For the numerical study of the beam injection process into the LHC, several technical and beam dynamical effects have to be taken into account, e.g. closed orbit variations of the pre-accelerator SPS, ripples on extraction and injection kickers, optics of the LHC itself and the behaviour of its transverse feedback system. Prominent beam dynamical effects are coupled bunch instabilities caused for example by the vacuum chamber resistance. This paper describes a fast approximate calculation of the beam deflection due to the wake field which is built up by the vacuum chamber resistance and caused by a large number of previous bunches and/or bunch passages. The code has been implemented into the framework of the CNGS extraction simulations [1] and the results are compared with measurements [2].

  7. Fast beam cut-off method in RF-knockout extraction for spot-scanning

    CERN Document Server

    Furukawa, T

    2002-01-01

    An irradiation method with magnetic scanning has been developed in order to provide accurate irradiation even for an irregular target shape. The scanning method has strongly required a lower ripple of the beam spill and a faster response to beam-on/off in slow extraction from a synchrotron ring. At HIMAC, RF-knockout extraction has utilized a bunched beam to reduce the beam-spill ripple. Therefore, particles near the resonance can be spilled out from the separatrices by synchrotron oscillation as well as by a transverse RF field. From this point of view, a fast beam cut-off method has been proposed and verified by both simulations and experiments. The maximum delay from the beam cut-off signal to beam-off has been improved to around 60 mu s from 700 mu s by a usual method. Unwanted dose has been considerably reduced by around a factor of 10 compared with that by the usual method.

  8. Measurements of an ion beam diameter extracted into air through a large-bore metal capillary

    Energy Technology Data Exchange (ETDEWEB)

    Hirano, Y.; Umigishi, M. [Graduate School of Humanities and Sciences, Nara Women’s University, Nara 630-8506 (Japan); Ishii, K.; Ogawa, H. [Department of Physics, Nara Women’s University, Nara 630-8506 (Japan)

    2015-07-01

    To extract an ion beam into air, the technique using a single macro-capillary has been paid attention. We have expanded the bore of the metal capillary up to 500 μm∅ inlet diameter to increase the beam intensity and have measured the intensity distributions of the extracted 3 MeV proton beam. Furthermore, we have tilted the capillary angle and measured the intensity distributions of the ion beam. In this article, we will present the experimental results together with the simulation which takes the tilt angles of the capillary into account.

  9. Measurements of an ion beam diameter extracted into air through a large-bore metal capillary

    International Nuclear Information System (INIS)

    To extract an ion beam into air, the technique using a single macro-capillary has been paid attention. We have expanded the bore of the metal capillary up to 500 μm∅ inlet diameter to increase the beam intensity and have measured the intensity distributions of the extracted 3 MeV proton beam. Furthermore, we have tilted the capillary angle and measured the intensity distributions of the ion beam. In this article, we will present the experimental results together with the simulation which takes the tilt angles of the capillary into account

  10. Modeling of direct beam extraction for a high-charge-state fusion driver

    Science.gov (United States)

    Anderson, O. A.; Grant Logan, B.

    A newly proposed type of multicharged ion source offers the possibility of an economically advantageous high-charge-state fusion driver. Multiphoton absorption in an intense uniform laser focus can give multiple charge states of high purity, simplifying or eliminating the need for charge-state separation downstream. Very large currents (hundreds of amperes) can be extracted from this type of source. Several arrangements are possible. For example, the laser plasma could be tailored for storage in a magnetic bucket, with beam extracted from the bucket. A different approach, described in this report, is direct beam extraction from the expanding laser plasma. We discuss extraction and focusing for the particular case of a 4.1 MV beam of Xe 16+ ions. The maximum duration of the beam pulse is limited by the total charge in the plasma, while the practical pulse length is determined by the range of plasma radii over which good beam optics can be achieved. The extraction electrode contains a solenoid for beam focusing. Our design studies were carried out first with an envelope code and then with a self-consistent particle code. Results from our initial model showed that hundreds of amperes could be extracted, but that most of this current missed the solenoid entrance or was intercepted by the wall and that only a few amperes were able to pass through. We conclude with an improved design which increases the surviving beam to more than 70 A.

  11. Beam-beam effects under the influence of external noise

    OpenAIRE

    Ohmi, K.

    2014-01-01

    Fast external noise, which gives fluctuation into the beam orbit, is discussed in connection with beam-beam effects. Phase noise from crab cavities and detection devices (position monitor) and kicker noise from the bunch by bunch feedback system are the sources. Beam-beam collisions with fast orbit fluctuations with turn by turn or multi-turn correlations, cause emittance growth and luminosity degradation. We discuss the tolerance of the noise amplitude for LHC and HL-LHC.

  12. New results on simulation of the nuclotron beam extraction with a bent crystal

    International Nuclear Information System (INIS)

    Extraction of relativistic deuteron beam from the Nuclotron with bent tungsten and silicon crystals was studied by simulation with taking into account ionization energy losses of particles and real accelerator acceptance. The dependence of extraction efficiency on the crystal radius, thickness, and orientation is discussed. The possibility of increasing the extraction efficiency with the crystal thickness increase is analyzed. It was shown that particle scattering in the holder material does not reduce significantly the extraction efficiency

  13. Negative hydrogen ion beam extraction from an AC heated cathode driven Bernas-type ion source

    Science.gov (United States)

    Okano, Y.; Miyamoto, N.; Kasuya, T.; Wada, M.

    2015-04-01

    A plasma grid structure was installed to a Bernas-type ion source used for ion implantation equipment. A negative hydrogen (H-) ion beam was extracted by an AC driven ion source by adjusting the bias to the plasma grid. The extracted electron current was reduced by positively biasing the plasma grid, while an optimum plasma grid bias voltage for negative ion beam extraction was found to be positive 3 V with respect to the arc chamber. Source operations with AC cathode heating show extraction characteristics almost identical to that with DC cathode heating, except a minute increase in H- current at higher frequency of cathode heating current.

  14. AA, view into the tank for the stochastic precooling kicker

    CERN Multimedia

    1979-01-01

    The kicker for the fast stochastic cooling of the freshly injected antiprotons was installed in this tank. A shutter shielded the deeply cooled antiproton stack from the violent action of the precooling kicker. The injection orbit is to the left, the stack orbit far to the right. After several seconds of precooling (in momentum and in the vertical plane), the shutter was opened briefly, so that by means of RF the precooled antiprotons could be transferred to the stack tail, where they were subjected to further cooling in momentum and both transverse planes. The fast shutter, which had to open and close in a fraction of a second, was an essential item of the cooling scheme and a mechanical masterpiece. See also 7910267, 8002234.

  15. Slot-type pickup/kicker for AA stochastic cooling

    CERN Multimedia

    1979-01-01

    A "slotted transmission line" was used for both pickups and kickers of the cooling systems of the AA. They served for the cooling of the high-density antiproton stack, in momentum and both transverse planes. In the beginning in a single band, 1-2 GHz, later in 2 bands, 2-4 and 4-8 GHz. Here we see the slotted electrodes partly pulled out of the outer casing. See also 7906189, 7906581X, 7896193.

  16. Proton extraction from a high-energy beam with bent crystals

    CERN Document Server

    Klem, J T

    1998-01-01

    Extraction with a bent crystal seems to be the only feasible option for providing the possibility for a fixed-target facility at future high-energy hadron colliders such as the LHC. If the extraction set-up is carefully designed and integrated with the beam cleaning system, a crystal could be used in a parasitic mode, i.e. without disturbing the collider experiments and using only particles that would be lost otherwise. Crystal assisted extraction has been studied at the CERN SPS. Different crystal designs and beam excitation methods have been used. Extraction efficiencies above 15% have been measured. The existence and importance of multi-pass extraction has been demonstrated with a crystal that does not allow single-pass extraction. The energy dependence of crystal extraction has been measured at three beam energies, and found to be in very good agreement with expectations. It has also been shown that the procedure for setting up extraction with a crystal is fast and easy, and that the extracted beam is ver...

  17. A compact proton synchrotron based on a low emittance beam extraction scheme using transverse RF noise

    International Nuclear Information System (INIS)

    A compact proton synchrotron for cancer therapy is presented. In the synchrotron, a new operating scheme for resonant beam extraction is applied with a combined function lattice in order to realize small emittance of the extracted beam with simple control for the accelerator system. In the extraction, the amplitude of the betatron oscillations of the particles inside the separatrix is increased by a transverse RF noise with a narrow bandwidth. During the extraction, the separatrix is kept constant, that is, the magnet currents related to the resonance are kept constant. The emittance of the extracted beam can be kept lower than about 0.1πmm · mrad without dynamic control of the closed orbit. (author)

  18. Simulating the Beam-line at CERN's ISOLDE Experiment

    CERN Document Server

    McGrath, Casey

    2013-01-01

    Maximizing the optical matching along portions of the ISOLDE beam-line and automating this procedure will make it easier for scientists to determine what the strengths of the electrical elds of each beam-line element should be in order to reduce particle loss. Simulations are run using a program called MAD-X, however, certain issues were discovered that hindered an immediate success of the simulations. Specifically, the transfer matrices for electrostatic components like the switchyards, kickers, and electric quadrupoles were missing from the original coding. The primary aim of this project was to design these components using AutoCAD and then extract the transfer matrices using SIMION. Future work will then implement these transfer matrices into the MAD-X code to make the simulations of the beam-line more accurate.

  19. Estimation of acceptance of the beam extraction system of K500 superconducting cyclotron

    International Nuclear Information System (INIS)

    The extraction system of the KSOO superconducting cyclotron consists of two electrostatic deflectors and eight passive magnetic channels, spanning over an azimuthal length of 330 degrees, with radial aperture of ∼6 mm. The radial position of the elements can be varied within ±6 mm. The extraction path is within the fringing field of the cyclotron. So, different positions of the magnetic elements change the optical properties of the extraction system, as seen by the beam. Here we have approximated the entire extraction path by a series of equivalent combined function magnetic elements, having variable field and gradient for different ion species and energies. The acceptance of the extraction system at the entry of first deflector has been determined. The accelerated beam can be extracted only if its emittance matches with this acceptance aperture. The acceptance calculation also predicts the tolerance limit of the magnetic field imperfections in the acceleration zone. (author)

  20. Beam Extraction for 1-MV Electrostatic Accelerator at the 300 kV Test Stand

    International Nuclear Information System (INIS)

    The Korea Multipurpose Accelerator Complex (KOMAC) has been developing a 300-kV test stand for a 1-MV electrostatic accelerator ion source. The ion source in the high-pressure vessel is required to have a high reliability. The test stand has been proposed and developed to confirm the stable operating conditions of the ion source. The ion source will be tested at the test stand to verify the long-time operating conditions. The test stand comprises a 300-kV high-voltage terminal, a battery for the ion-source power, a 60-Hz inverter, 200-MHz RF power, a 5-kV extraction power supply, a 300-kV accelerating tube, and a vacuum system. A beam extraction experiment for the test stand was performed, and the beam current was measured using a faraday cup in the chamber. A beam extraction results for the RF ion source will be presented. Beam extraction from the RF ion source of the test stand is verified by measuring the beam current with a faraday cup in the chamber. Thus far NI Labview, PLC and faraday cup have been used to measure the beam current. The OPC server is useful for monitoring the PLC values. The average beam current of (a), (b) and (c) shown in figure 2 are 110.241µA, 105.8597µA and 103.5278µA respectively

  1. Extraction of the Proton Beam from the 70 GeV IHEP Accelerator

    OpenAIRE

    A.G. Afonin; Baranov, V. T.; Biryukov, V. M.; Ivanov, I. M.; Kardash, A. A.; Kotov, V. I.; Maisheev, V. A.; Terekhov, V. I.; Troyanov, E. F.; Fedotov, Yu. S.; Chepegin, V. N.; Chesnokov, Yu. A.

    2005-01-01

    This paper presents the physical background for particle extraction from IHEP accelerator using short bent silicon crystals, analyses the results of the studies, considers in detail the regime of simultaneous work of crystal extraction and several internal targets. It is experimentally shown that the use of short crystals allows the extraction of beams with intensity of 10e12 proton/cycle with efficiency of 85%.

  2. Test bench to commission a third ion source beam line and a newly designed extraction system.

    Science.gov (United States)

    Winkelmann, T; Cee, R; Haberer, T; Naas, B; Peters, A

    2012-02-01

    The HIT (Heidelberg Ion Beam Therapy Center) is the first hospital-based treatment facility in Europe where patients can be irradiated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. In the future a helium beam for regular patient treatment is requested, therefore a third ion source (Supernanogan source from PANTECHNIK S.A.) will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line is installed at a test bench at HIT to commission and validate this section. Measurements with different extraction system setups will be presented to show the improvement of beam quality for helium, proton, and carbon beams. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed. PMID:22380336

  3. Test bench to commission a third ion source beam line and a newly designed extraction system

    International Nuclear Information System (INIS)

    The HIT (Heidelberg Ion Beam Therapy Center) is the first hospital-based treatment facility in Europe where patients can be irradiated with protons and carbon ions. Since the commissioning starting in 2006 two 14.5 GHz electron cyclotron resonance ion sources are routinely used to produce a variety of ion beams from protons up to oxygen. In the future a helium beam for regular patient treatment is requested, therefore a third ion source (Supernanogan source from PANTECHNIK S.A.) will be integrated. This third ECR source with a newly designed extraction system and a spectrometer line is installed at a test bench at HIT to commission and validate this section. Measurements with different extraction system setups will be presented to show the improvement of beam quality for helium, proton, and carbon beams. An outlook to the possible integration scheme of the new ion source into the production facility will be discussed.

  4. The possibility of parasitic 20 TeV beams extracted from the SSC using bent crystals

    International Nuclear Information System (INIS)

    The need for an SSC test beam of energy greater than one TeV was discussed in Snowmass 86; Such a beam could be created from the neutral debris from an interaction region as a parasitic operation. In the same reference, the possibility of extracting a 20 TeV beam with a bent crystal was mentioned. This year it is more apparent that a low intensity, 20 TeV extracted bean would be highly desirable. Experiments which study the properties of short lived particles, for which the average decay path is long in the lab frame in a fixed target experiment, can be done in such a beam. In particular, a fixed target Beauty detector running at Fermilab would require about 108 protons per second. In this paper, the authors explore in some detail the possible yield of a bent crystal beam and its impact on collider operations

  5. Computer simulation of 2-D and 3-D ion beam extraction and acceleration

    Energy Technology Data Exchange (ETDEWEB)

    Ido, Shunji; Nakajima, Yuji [Saitama Univ., Urawa (Japan). Faculty of Engineering

    1997-03-01

    The two-dimensional code and the three-dimensional code have been developed to study the physical features of the ion beams in the extraction and acceleration stages. By using the two-dimensional code, the design of first electrode(plasma grid) is examined in regard to the beam divergence. In the computational studies by using the three-dimensional code, the axis-off model of ion beam is investigated. It is found that the deflection angle of ion beam is proportional to the gap displacement of the electrodes. (author)

  6. Results from the 2009 beam commissioning of the CERN multi-turn extraction

    CERN Document Server

    Benedetto, E; Bohl, T; Cettour Cave, S; Cornelis, K; Cotte, D; Damerau, H; Delrieux, M; Fleuret, J; Fowler, T; Follin, F; Franchi, A; Freyermuth, P; Genoud, H; Gilardoni, S; Giovannozzi, M; Hancock, S; Hans, O; Le Borgne, Y; Manglunki, D; Matli, E; Métral, E; Métral, G; Newman, M; Pereira, L; Peters, F; Riva, Y; Roncarolo, F; Sermeus, L; Steerenberg, R; Vandorpe, B; Wenninger, J

    2010-01-01

    Following the analysis of the results obtained during the first year of beam commissioning of the CERN multiturn extraction, a number of changes have been introduced in the beam manipulations performed in the CERN Proton Synchrotron. This includes a different control of the linear chromaticity, the setting of the nonlinear magnets used to split the beam, and the longitudinal structure in the PS. The results obtained during the 2009 run are presented and discussed in detail, including the beam performance in both the PS and the SPS.

  7. Studies of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Toivanen, V., E-mail: ville.aleksi.toivanen@cern.ch; Küchler, D. [European Organization for Nuclear Research (CERN), 1211 Geneva 23 (Switzerland)

    2016-02-15

    The 14.5 GHz GTS-LHC Electron Cyclotron Resonance Ion Source (ECRIS) provides multiply charged heavy ion beams for the CERN experimental program. The GTS-LHC beam formation has been studied extensively with lead, argon, and xenon beams with varied beam extraction conditions using the ion optical code IBSimu. The simulation model predicts self-consistently the formation of triangular and hollow beam structures which are often associated with ECRIS ion beams, as well as beam loss patterns which match the observed beam induced markings in the extraction region. These studies provide a better understanding of the properties of the extracted beams and a way to diagnose the extraction system performance and limitations, which is otherwise challenging due to the lack of direct diagnostics in this region and the limited availability of the ion source for development work.

  8. Studies of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    International Nuclear Information System (INIS)

    The 14.5 GHz GTS-LHC Electron Cyclotron Resonance Ion Source (ECRIS) provides multiply charged heavy ion beams for the CERN experimental program. The GTS-LHC beam formation has been studied extensively with lead, argon, and xenon beams with varied beam extraction conditions using the ion optical code IBSimu. The simulation model predicts self-consistently the formation of triangular and hollow beam structures which are often associated with ECRIS ion beams, as well as beam loss patterns which match the observed beam induced markings in the extraction region. These studies provide a better understanding of the properties of the extracted beams and a way to diagnose the extraction system performance and limitations, which is otherwise challenging due to the lack of direct diagnostics in this region and the limited availability of the ion source for development work

  9. Studies of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN.

    Science.gov (United States)

    Toivanen, V; Küchler, D

    2016-02-01

    The 14.5 GHz GTS-LHC Electron Cyclotron Resonance Ion Source (ECRIS) provides multiply charged heavy ion beams for the CERN experimental program. The GTS-LHC beam formation has been studied extensively with lead, argon, and xenon beams with varied beam extraction conditions using the ion optical code IBSimu. The simulation model predicts self-consistently the formation of triangular and hollow beam structures which are often associated with ECRIS ion beams, as well as beam loss patterns which match the observed beam induced markings in the extraction region. These studies provide a better understanding of the properties of the extracted beams and a way to diagnose the extraction system performance and limitations, which is otherwise challenging due to the lack of direct diagnostics in this region and the limited availability of the ion source for development work. PMID:26932095

  10. Studies of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    Science.gov (United States)

    Toivanen, V.; Küchler, D.

    2016-02-01

    The 14.5 GHz GTS-LHC Electron Cyclotron Resonance Ion Source (ECRIS) provides multiply charged heavy ion beams for the CERN experimental program. The GTS-LHC beam formation has been studied extensively with lead, argon, and xenon beams with varied beam extraction conditions using the ion optical code IBSimu. The simulation model predicts self-consistently the formation of triangular and hollow beam structures which are often associated with ECRIS ion beams, as well as beam loss patterns which match the observed beam induced markings in the extraction region. These studies provide a better understanding of the properties of the extracted beams and a way to diagnose the extraction system performance and limitations, which is otherwise challenging due to the lack of direct diagnostics in this region and the limited availability of the ion source for development work.

  11. LHC Report: The beam is back at the LHC

    CERN Multimedia

    Reyes Alemany

    2015-01-01

    A series of sector beam tests paved the way for the start-up of the LHC in 2008 and 2009. These tests and the follow-up of the issues that arose were part of the process that led to a smooth start-up with beam.   Given this experience, sector tests were scheduled to take place several weeks before the 2015 start-up. On the weekend of 6-9 March, beam from the SPS was injected into both LHC injection regions, followed by a first pass through the downstream LHC sectors. For the clockwise LHC beam (called “beam 1”) this meant passing through ALICE and into Sector 2-3, while the anticlockwise beam (called “beam 2”) was threaded through LHCb and all the way from Point 8 to Point 6, where it was extracted by the beam dump kickers onto the beam dump block. The dry runs in the previous weeks were mainly targeted at preparation for the sector tests. The systems tested included: injection, timing, synchronisation and beam instrumentation. The beam interlock ...

  12. Programmable extraction of different energy proton beam to an experimental facility in the process of injection into the IHEP synchrotron

    International Nuclear Information System (INIS)

    The programmable different energy proton beam extraction to an experimental facility of the IHEP under injection to the IHEP proton synchrotron is realized in the following way; after inquiry from the IHEP EF transfer to a lower extraction energy and beam extraction to EF are performed. 1 ref.; 1 fig

  13. Optimization of cold neutron beam extraction at ESS

    DEFF Research Database (Denmark)

    Schönfeldt, Troels; Batkov, K.; Klinkby, Esben Bryndt;

    The present study takes its origin in the baseline design of European Spallation Source where a cold and a thermal moderator are situated next to each other enabling bispectral extraction. The study aims at mapping the differences in various neutron distributions depending on the angle and position...... from which the moderator is viewed. This study does not only show changes in both cold and thermal neutron flux, depending on extraction position, but also shows that there are significant differences in the wavelength spectrum and origin of neutrons depending on the angel of view....

  14. Challenges and plans for injection and beam dump

    CERN Document Server

    Barnes, M; Mertens, V; Uythoven, J

    2015-01-01

    The injection and beam dumping systems of the LHC will need to be upgraded to comply with the requirements of operation with the HL-LHC beams. The elements of the injection system concerned are the fixed and movable absorbers which protect the LHC in case of an injection kicker error and the injection kickers themselves. The beam dumping system elements under study are the absorbers which protect the aperture in case of an asynchronous beam dump and the beam absorber block. The operational limits of these elements and the new developments in the context of the HL-LHC project are described.

  15. Tailoring phase-space in neutron beam extraction

    International Nuclear Information System (INIS)

    In view of the trend towards smaller samples and experiments under extreme conditions it is important to deliver small and homogeneous neutron beams to the sample area. For this purpose, elliptic and/or Montel mirrors are ideally suited as the phase space of the neutrons can be defined far away from the sample. Therefore, only the useful neutrons will arrive at the sample position leading to a very low background. We demonstrate the ease of designing neutron transport systems using simple numeric tools, which are verified using Monte-Carlo simulations that allow taking into account effects of gravity and finite beam size. It is shown that a significant part of the brilliance can be transferred from the moderator to the sample. Our results may have a serious impact on the design of instruments at spallation sources such as the European Spallation Source (ESS) in Lund, Sweden

  16. RF-knockout Extraction System for the CNAO Synchrotron

    CERN Document Server

    Carmignani, Nicola; Serio, Mario; Balbinot, Giovanni; Bressi, Erminia; Caldara, Michele; Pullia, Marco; Bosser, Jacques; Venchi, Giuseppe

    2010-01-01

    The National Centre for Oncological Hadrontherapy (CNAO) is a centre in Italy for the treatment of patients affected by tumours with proton and carbon ions beams accelerated in a synchrotron. The synchrotron extraction method is based on the use of a betatron core. This work aims to verify, through a theoretical study and a simulation, the possibility of using the RF-knockout extraction method exploiting the existing hardware. A simulation program has been written to simulate the extraction system of the synchrotron with the purpose to define the parameters of the radio frequency. Two types of radio frequencies have been compared in order to obtain a constant spill with the minimum ripple: a carrier wave with a frequency and amplitude modulation, and a gaussian narrow band noise modulated in amplitude. Results of the simulation and considerations on the kicker characteristics are presented

  17. Particle beam extraction at the Orsay cryogenic coil cyclotron

    International Nuclear Information System (INIS)

    We are presenting the design and the performance of the single turn extraction in the Orsay cryogenic cyclotron. After a careful shaping of the average magnetic field in the extraction area for a representative set of particles, we get the various expected corresponding νsub(r) (νsub(s)) diagrams and then the corrected diagram of the kinetic energy per nucleon T at the exit vs Z/A. The study of the accelerated orbits till the entrance in the extraction devices shows the turn separation is sufficient to allow the insertion of an electrostatic septum and satisfying energies and RF phases are obtained. The designed extraction devices are successively: an electrostatic deflector, located in a hill, with an electric field 100 kV/cm, an iron free channel, located in the following hill, having to produce a field drop 0.25 T, some magnetostatic channels for radial focusing. A quick look at the technological features of the electromagnetic channel is given proving its possibility

  18. MEASURED TRANSVERSE COUPLING IMPEDANCE OF RHIC INJECTION AND ABORT KICKERS

    International Nuclear Information System (INIS)

    Concerns regarding possible transverse instabilities in RHIC and the SNS pointed to the need for measurements of the transverse coupling impedance of ring components. The impedance of the RHIC injection and abort kicker was measured using the conventional method based on the S21 forward transmission coefficient. A commercial 450 Ω twin-wire Lecher line were used and the data was interpreted via the log-formula. All measurements, were performed in test stands fully representing operational conditions including pulsed power supplies and connecting cables. The measured values for the transverse coupling impedance in kick direction and perpendicular to it are comparable in magnitude, but differ from Handbook predictions

  19. Magnetic field extraction of trap-based electron beams using a high-permeability grid

    International Nuclear Information System (INIS)

    A method to form high quality electrostatically guided lepton beams is explored. Test electron beams are extracted from tailored plasmas confined in a Penning-Malmberg trap. The particles are then extracted from the confining axial magnetic field by passing them through a high magnetic permeability grid with radial tines (a so-called “magnetic spider”). An Einzel lens is used to focus and analyze the beam properties. Numerical simulations are used to model non-adiabatic effects due to the spider, and the predictions are compared with the experimental results. Improvements in beam quality are discussed relative to the use of a hole in a high permeability shield (i.e., in lieu of the spider), and areas for further improvement are described

  20. Gas-discharge electron tube with beam extraction into mean-pressure gas

    Energy Technology Data Exchange (ETDEWEB)

    Gitt, V.D.; Noskov, D.A.; Orlikov, L.N.; Ryltsev, P.I.; Tikhomirov, S.I.; Chikin, E.V. (Tomskij Inst. Avtomatizirovannykh Sistem Upravleniya i Radioehlektroniki (USSR))

    Described is an electron gun on the base of high-voltage glow supplied with a gas-dynamical window for electron beam extraction into gas 10/sup 3/-10/sup 5/ Pa. The gun discharge system comprises cold aluminium cathode and sectional anode formed by three copper disks with axial holes. The gun is intended for operation in a continuous mode at accelerating voltage up to 60 kV and 30 mA discharge current as well as for experimental investigations of electron beam scattering at average pressure. Measurements of current density distribution by cross section of extracted beams are conducted and images of gas ionization zones are taken by 20-60 keV electron beam at nitrogen pressure 1.3-2 kPa.

  1. Gas-discharge electron tube with beam extraction into mean-pressure gas

    International Nuclear Information System (INIS)

    Described is an electron gun on the base of high-voltage glow supplied with a gas-dynamical window for electron beam extraction into gas 103-105 Pa. The gun discharge system comprises cold aluminium cathode and sectional anode formed by three copper disks with axial holes. The gun is intended for operation in a continuous mode at accelerating voltage up to 60 kV and 30 mA discharge current as well as for experimental investigations of electron beam scattering at average pressure. Measurements of current density distribution by cross section of extracted beams are conducted and images of gas ionization zones are taken by 20-60 keV electron beam at nitrogen pressure 1.3-2 kPa

  2. Design of inductively detuned RF extraction cavities for the Relativistic Klystron Two Beam Accelerator

    International Nuclear Information System (INIS)

    An inductively detuned traveling wave cavity for the Relativistic Klystron Two Beam Accelerator expected to extract high RF power at 11. 424 GHz for the 1 TeV Center of Mass Next Linear Collider has been designed. Longitudinal beam dynamics studies led to the following requirements on cavity design: (a) Extraction of 360 MW of RF power with RF component of the current being 1.15 kAmps at 11.424 GHz, (b) Inductively detuned traveling wave cavity with wave phase velocity equal to 4/3 the speed of light, (c) Output cavity with appropriate Qext and eigenfrequency for proper matching. Furthermore, transverse beam dynamics require low shunt impedances to avoid the beam break-up instability. We describe the design effort to meet these criteria based on frequency-domain and time-domain computations using 2D- and 3D- electromagnetic codes

  3. MICRO-BUNCHING OF THE AGS SLOW EXTRACTED BEAM FOR A RARE KAON DECAY SEARCH.

    Energy Technology Data Exchange (ETDEWEB)

    GLENN,J.; SIVERTZ,M.; CHIANG,I.; LAZARUS,D.; KOSCIELNIAK,S.

    2001-06-18

    The AGS Slow Extracted Beam (SEB) must be chopped with 250 ps bursts every 40 ns to permit time-of-flight (ToF) measurement of the secondary K{sup 0} beam. Standard techniques to produce this level of bunching would require excessive rf voltage, thus we have developed a ''Micro-Bunching'' technique of extracting the beam as it is forced between empty rf buckets. A specification of the required rf system will be given. Four-dimensional model simulations of particle dynamics for the planned rf and extraction systems will be shown. Simulations of previous tests along with the test measurements are also presented. Measurement of tight bunching requires dedicated instrumentation. The design of a detector system to measure bunch widths and the extinction factor between bunches will be given; considerations include the various particles produced and transported, timing precision and background.

  4. Beam-Based Alignment, Tuning and Beam Dynamics Studies for the ATF2 Extraction Line and Final Focus System

    International Nuclear Information System (INIS)

    Using a new extraction line currently under construction, the ATF2 experiment plans to test the novel compact final focus optics design with local chromaticity correction intended for use in future linear colliders. With a 1.3 GeV design beam of 30nm normalized vertical emittance extracted from the ATF damping ring, the primary goal is to achieve a vertical spot-size at the IP waist of 37nm. We discuss our planned strategy for tuning the ATF2 beam to meet the primary goal. Simulation studies have been performed to asses the effectiveness of the strategy, including 'static' (installation) errors and dynamical effects (ground-motion, mechanical vibration, ring extraction jitter etc.). We have simulated all steps in the tuning procedure, from initial orbit establishment to final IP spot-size tuning. Through a Monte Carlo study of 100's of simulation seeds we find we can achieve a spot-size within ∼10% of the design optics value in at least 75% of cases. We also ran a simulation to study the long-term performance with the use of beam-based feedbacks

  5. Transportation system for heavy ion beams extracted from cyclotron DC-60

    International Nuclear Information System (INIS)

    Calculations of the extraction channels of the heavy ion beams extracted from the DC-60 cyclotron were carried out. On the basis of these calculations the extraction channels were designed and manufactured. Channel 1 has the length of about 14.4 m from its beginning to the target and is intended for film irradiation by different types of heavy ions. Focusing of the extracted ion beams on channel 1 is carried out by two quadrupoles. The ion beam scanning system (vertical and horizontal magnetic scanners) is situated after the bending magnet. Channels 2 and 3 work when the bending magnet is switched on. It deflects the ion beams at the angle ± 30 deg. The quadrupole doublets are situated after the bending magnet in channels 2 and 3. The tables of calculated gradients in all quadrupoles and dependences of the beam semidimensions along the channels for different points of the cyclotron operating diagram are given. The characteristics of the basic optical elements of the channels are also given here

  6. Literature search on Kickers and Septa for the Amsterdam Pulse Stretcher

    International Nuclear Information System (INIS)

    Literature search has yielded a qualitative and quantitative view on kickers. Quantitatively specifications on designs in literature have been collected. The UPDATE-kickers have been given the following specs: deflection angle 2 mrad, pulsewidth 2 μs, falltime 70 ns, available length about 2 m. Undertaken is a comparison of characteristic parameters: kick strength (energy x angle), pulse characteristics (pulsewidth/falltime) and required peak power. Realisation of the pulse characteristics will impose the greatest requirements on the UPDATE-kicker design. The comparison has shown correspondence with two ferrite kicker designs (CERN-CPS and ELSA), the Los Alamos TEM-kicker and the electrostatic kicker from Saskatoon. On account of the relative simplicity of construction and pulse forming network the Saskatoon kicker has been chosen as the starting point for a design study. Design calculations will proceed from a length of 1.6 m and a gap of 4 cm between two parallel plates at a potential difference of 50 kV. Literature search on septa resulted in an overview on septum magnets and electrostatic wire septa. 72 refs.; 14 figs.; 2 tabs

  7. Extractable proteins from electron beam (EB) irradiated natural rubber (NR) latex

    International Nuclear Information System (INIS)

    The protein assay of natural rubber latex (NRL) vulcanized by low energy electron beam (EB, 300 keV, 30 mA) has been carried out using Bicinchoninic acid (BCA) reagent. Extractable protein in irradiated latex film was determined by measuring the absorption of colored solution at 562 nm using UV spectrometer. The effect of various radiation doses on the extractable protein content of NRL was investigated. It was ,found that the quantities of extractable protein increases with radiation dose. When compared with ,gamma-ray irradiated samples the same trend was observed. Electron beam irradiated latex films are leached in 1% (ammonia water for various lengths of time. From the results it was established that within 2 hours of leaching in ammonia water most of the extractable protein (96%) were removed from rubber film

  8. Design, analysis and measurement of very fast kicker magnets at SLAC

    International Nuclear Information System (INIS)

    Recent experience with SLC has shown that very fast, ferrite-loaded, transmission-line, beam-kicker magnets can cause significant and undesirable distortion of a 1.5-2.5 kA, 20-4- kV pulse as it travels through the magnet. In general, there is a net lengthening of the pulse, with increases in its rise and fall times, a decrease in amplitude, and an unsymmetrical rounding of the flattop. In this partially tutorial treatise, a number of practical design considerations are discussed in terms of equivalent circuits, magnet circuit dispersion and dissipation, undesired circuit shunting and coupling, high-voltage breakdown problems and high-order-mode losses that lead to beam tube heating. These effects are linked to the properties of the materials, the presence of radiation and realizable magnet topologies. Measurements and calculations of some of these characteristics for several magnet designs are reviewed. The results presented come from a truly eclectic effort. 8 refs., 1 fig

  9. High efficiency energy extraction from a relativistic electron beam in a strongly tapered undulator

    CERN Document Server

    Sudar, Nicholas; Duris, Joe; Gadjev, Ivan; Polyaniy, Mikhail; Pogorelsky, Igor; Fedurin, Mikhail; Swinson, Christina; Babzien, Marcus; Kusche, Karl; Gover, Avi

    2016-01-01

    We present results of an experiment where, using a 200 GW CO2 laser seed, a 65 MeV electron beam was decelerated down to 35 MeV in a 54 cm long strongly tapered helical magnetic undulator, extracting over 30$\\%$ of the initial electron beam energy to coherent radiation. These results demonstrate unparalleled electro-optical conversion efficiencies for a relativistic beam in an undulator field and represent an important step in the development of high peak and average power coherent radiation sources.

  10. Accelerator System Design, Injection, Extraction and Beam-Material Interaction: Working Group C Summary Report

    CERN Document Server

    Mokhov, N V

    2014-01-01

    The performance of high beam power accelerators is strongly dependent on appropriate injection, acceleration and extraction system designs as well as on the way interactions of the beam with machine components are handled. The experience of the previous ICFA High -Brightness Beam workshops has proven that it is quite beneficial to combine analyses and discussion of these issues in one group. A broad range of topics was presented and discussed at the Working Group C sessions at the HB2012 Workshop. Highlights from the talks, outstanding issues along with plans and proposals for future work are briefly described in this report.

  11. Instrumentation and beam dynamics study of advanced electron-photon facility in Indiana University

    Science.gov (United States)

    Luo, Tianhuan

    The Advanced eLectron-PHoton fAcility (ALPHA) is a compact electron accelerator under construction and being commissioned at the Indiana University Center for Exploration of Energy and Matter (CEEM). In this thesis, we have studied the refurbished Cooler Injector Synchrotron (CIS) RF cavity using both the transmission line model and SUPERFISH simulation. Both low power and high power RF measurements have been carried out to characterize the cavity. Considering the performance limit of ferrite, we have designed a new ferrite loaded, co-axial quarter wave like cavity with similar structure but a more suitable ferrite material. We have also designed a traveling wave stripline kicker for fast extraction by POISSON and Microwave Studio. The strips' geometry is trimmed to maximize the uniformity of the kicking field and match the impedance of the power cables. The time response simulation shows the kicker is fast enough for machine operation. The pulsed power supply requirement has also been speci ed. For the beam diagnosis in the longitudinal direction, we use a wideband Wall Gap Monitor (WGM) served in CIS. With proper shielding and amplification to get good WGM signal, we have characterized the injected and extracted beam signal in single pass commissioning, and also verified the debunching effect of the ALPHA storage ring. A modulation-demodulation signal processing method is developed to measure the current and longitudinal profile of injected beam. By scanning the dipole strength in the injection line, we have reconstructed the tomography of the longitudinal phase space of the LINAC beam. In the accumulation mode, ALPHA will be operated under a low energy and high current condition, where intra beam scattering (IBS) becomes a dominant effect on the beam emittance. A self consistent simulation, including IBS effect, gas scattering and linear coupling, has been carried out to calculate the emittance of the stored beam.

  12. Instrumentation and Beam Dynamics Study of Advanced Electron-Photon Facility in Indiana University

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Tianhuan [Indiana Univ., Bloomington, IN (United States)

    2011-08-01

    The Advanced eLectron-PHoton fAcility (ALPHA) is a compact electron accelerator under construction and being commissioned at the Indiana University Center for Exploration of Energy and Matter (CEEM). In this thesis, we have studied the refurbished Cooler Injector Synchrotron (CIS) RF cavity using both the transmission line model and SUPERFISH simulation. Both low power and high power RF measurements have been carried out to characterize the cavity. Considering the performance limit of ferrite, we have designed a new ferrite loaded, co-axial quarter wave like cavity with similar structure but a more suitable ferrite material. We have also designed a traveling wave stripline kicker for fast extraction by POISSON and Microwave Studio. The strips geometry is trimmed to maximize the uniformity of the kicking field and match the impedance of the power cables. The time response simulation shows the kicker is fast enough for machine operation. The pulsed power supply requirement has also been specified. For the beam diagnosis in the longitudinal direction, we use a wideband Wall Gap Monitor (WGM) served in CIS. With proper shielding and amplification to get good WGM signal, we have characterized the injected and extracted beam signal in single pass commissioning, and also verified the debunching effect of the ALPHA storage ring. A modulation-demodulation signal processing method is developed to measure the current and longitudinal profile of injected beam. By scanning the dipole strength in the injection line, we have reconstructed the tomography of the longitudinal phase space of the LINAC beam. In the accumulation mode, ALPHA will be operated under a low energy and high current condition, where intra beam scattering (IBS) becomes a dominant effect on the beam emittance. A self consistent simulation, including IBS effect, gas scattering and linear coupling, has been carried out to calculate the emittance of the stored beam.

  13. Fields in multilayer beam tubes

    International Nuclear Information System (INIS)

    Equations are presented for calculating the fields from a bunched beam that penetrate into the layers of a beam tube of circular cross section. Starting from the radial wave impedance of an outer surface, the wave functions in inner layers are calculated numerically to obtain field strengths or the longitudinal beam impedance. Examples of a vertex-detector region and of an injection kicker are given

  14. Latest Performance Results from the FONT5 Intra-train Beam Position and Angle Feedback System at ATF2

    CERN Document Server

    Christian, G B; Bett, D R; Blaskovic Kraljevic, N; Burrows, P N; Davis, M R; Gerbershagen, A; Perry, C; Constance, B; Resta-Lopez, J

    2012-01-01

    A prototype Interaction Point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider, has been designed and tested on the extraction line of the KEK Accelerator Test Facility (ATF). The FONT5 intra-train feedback system aims to stabilize the beam orbit by correcting both the position and angle jitter in the vertical plane on bunch-tobunch time scales, providing micron-level stability at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kickerdrive amplifiers. The latest results from beam tests at ATF2 will be presented, including the system latency and correction performance.

  15. Portable test bench for the studies concerning ion sources and ion beam extraction and focusing systems

    International Nuclear Information System (INIS)

    A portable test bench is described, which was designed to check ion sources, ion beam extraction and focusing systems before its use in a 600 KeV Cockcroft-Walton accelerator. The vacuum possibilities of the system are specially analyzed in connection with its particular use. The whole can be considered as a portable accelerator of low energy (50 keV). (Author)

  16. Preliminary Simulation of Beam Extraction for the 28 GHz ECR Ion Source

    CERN Document Server

    Park, Bum-Sik; Choi, Seokjin

    2015-01-01

    The 28 GHz ECR(Electron Cyclotron Resonance) ion source is under development to supply various beams from proton to uranium at RISP(Rare Isotope Science Project). The superconducting magnet system for a 28 GHz ECR ion source consists of four solenoid coils and a saddle type sextupole. To meet the design requirement of ECR ion source, a numerical simulation was accomplished by using the KOBRA3-INP to optimize the extraction system which is the three dimensional ion optics code. The influence of the three dimensional magnetic field and the space charge effect was considered to extract the highly charged ion beam. In this paper, the design results of the extraction system were reported in detail.

  17. A study on effective extraction of isoflavones from soy germ using the electron beam

    International Nuclear Information System (INIS)

    Soy germ was irradiated with 2 MeV electron beam with different doses ranging from 1 to 20 kGy. The amount of isoflavones from irradiated soy germ was compared with those from natural soy germ by extracting with ethanol and methanol. The changed amounts of isoflavones were measured by high-performance liquid chromatography with standard calibration curve. Each extract of soy germ was quantified for antioxidant activity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging method. The amount of isoflavones was found to be increased after electron-beam irradiation. Particularly ethanol extract with 15 kGy irradiated soy germ contained the maximum amount of isoflavones. Antioxidant activity of irradiated soy germ was higher than that of natural soy germ.

  18. A study on effective extraction of isoflavones from soy germ using the electron beam

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jeong Hoon [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Choi, Tae Beom [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Department of Chemistry, Dongguk University, 3 Pildong, Chunggu, Seoul 100-715 (Korea, Republic of); Kim, Sang Wook [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of)], E-mail: swkim@kaeri.re.kr; Hur, Min Goo; Yang, Seung Dae [Radiation Research Division for Industry and Environment, Korea Atomic Energy Research Institute, 1266 Sinjeong-dong, Jeongup-si, 580-185 Jeollabuk-do (Korea, Republic of); Yu, Kook Hyun [Department of Chemistry, Dongguk University, 3 Pildong, Chunggu, Seoul 100-715 (Korea, Republic of)], E-mail: yukook@dongguk.edu

    2009-07-15

    Soy germ was irradiated with 2 MeV electron beam with different doses ranging from 1 to 20 kGy. The amount of isoflavones from irradiated soy germ was compared with those from natural soy germ by extracting with ethanol and methanol. The changed amounts of isoflavones were measured by high-performance liquid chromatography with standard calibration curve. Each extract of soy germ was quantified for antioxidant activity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging method. The amount of isoflavones was found to be increased after electron-beam irradiation. Particularly ethanol extract with 15 kGy irradiated soy germ contained the maximum amount of isoflavones. Antioxidant activity of irradiated soy germ was higher than that of natural soy germ.

  19. A study on effective extraction of isoflavones from soy germ using the electron beam

    Science.gov (United States)

    Park, Jeong Hoon; Choi, Tae Beom; Kim, Sang Wook; Hur, Min Goo; Yang, Seung Dae; Yu, Kook Hyun

    2009-07-01

    Soy germ was irradiated with 2 MeV electron beam with different doses ranging from 1 to 20 kGy. The amount of isoflavones from irradiated soy germ was compared with those from natural soy germ by extracting with ethanol and methanol. The changed amounts of isoflavones were measured by high-performance liquid chromatography with standard calibration curve. Each extract of soy germ was quantified for antioxidant activity with 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging method. The amount of isoflavones was found to be increased after electron-beam irradiation. Particularly ethanol extract with 15 kGy irradiated soy germ contained the maximum amount of isoflavones. Antioxidant activity of irradiated soy germ was higher than that of natural soy germ.

  20. Design of a kicker with a movable electrode for the FEATHER project

    CERN Document Server

    Delerue, N

    2003-01-01

    The design of a stripline kicker with a movable electrode for the FEATHER project is detailed here. More than 1000 simulations have been done with the POISSON/SUPERFISH code to study the impedance of various electrostatic configurations.

  1. Design and development of pulse power supply for transmission line type kicker magnet

    International Nuclear Information System (INIS)

    A 25 Hz kicker power supply has been designed and developed to test a 6.25 Ohm transmission line type kicker magnet for technological development. This power supply delivers a 1kA trapezoidal current pulse with a rise, fall and flat top time of 100 ns, 100 ns and 500 ns respectively. This current pulse is generated by discharging a pulse forming network into matched transmission line kicker magnet. A high voltage thyratron CX1666 is used as a switch. The design of PFN was a critical issue from the fabrication point of view due to smaller impedance and faster rise time requirement. We discuss the specific issues related to the design of pulse forming network and thyratron assembly for achieving faster rise time of current pulse. The designed and experimental results of the developed kicker power supplies will be also presented. (author)

  2. Production of a high-brightness beam using an optimized extraction system

    International Nuclear Information System (INIS)

    Ion beam lithography relies on high brightness beams in the micro-ampere range. For such intensities the saddle field ion source is a good choice as it offers high efficiency and easy operation. In the authors' system, two screening electrodes are enclosed between two ground electrodes and an annular anode, ensuring high operational reliability. Optimization of the extraction system was performed both by experiments and by calculations according to the rules of high current ion beam generation. The best result for nitrogen at a 13.5 keV beam energy was a 160 μA ion current with an emittance of 2.5 mm m rad. and an emittance-normalized brightness of 11.4 A/(mm m rad.)2. (author)

  3. Characterization of a metastable neon beam extracted from a commercial RF ion source

    International Nuclear Information System (INIS)

    We have used a commercial RF ion-source to extract a beam of metastable neon atoms. The source was easily incorporated into our existing system and was operative within a day of installation. The metastable velocity distribution, flux, flow, and efficiency were investigated for different RF powers and pressures, and an optimum was found at a flux density of 2 × 1012 atoms/s/sr. To obtain an accurate measurement of the amount of metastable atoms leaving the source, we insert a Faraday cup in the beam line and quench some of them using a weak 633 nm laser beam. In order to determine how much of the beam was quenched before reaching our detector, we devised a simple model for the quenching transition and investigated it for different laser powers. This detection method can be easily adapted to other noble gas atoms

  4. Characterization of a metastable neon beam extracted from a commercial RF ion source

    CERN Document Server

    Ohayon, B; Ron, G

    2015-01-01

    We have used a commercial RF ion-source to extract a beam of metastable neon atoms. The source was easily incorporated into our existing system and was operative within a day of installation. The metastable velocity distribution, flux, flow, and efficiency were investigated for different RF powers and pressures, and an optimum was found at a flux density of $2\\times10^{12}\\,$atoms/s/sr. To obtain an accurate measurement of the amount of metastable atoms leaving the source, we insert a Faraday cup in the beam line and quench some of them using a weak $633\\,$nm laser beam. In order to determine how much of the beam was quenched before reaching our detector, we devised a simple model for the quenching transition and investigated it for different laser powers. This detection method can be easily adapted to other noble gas atoms.

  5. Design of Air-Cooled Beam Dump for Extraction Line of PS Booster

    CERN Document Server

    Perillo-Marcone, A; Venturi, V; Antonakakis, T; Vlachoudis, V; Nowak, E; Mason, G; Battistin, M; Czapski, M; Sgobba, S

    2013-01-01

    A new beam dump has been designed, which withstands the future proton beam extracted from the Proton Syncrotron Booster (PSB) at CERN, consisting of up to 1E14 protons per pulse at 2 GeV after its upgrade in 2018/2019. In order to be able to efficiently release the deposited heat, the new dump will be made out of a single cylindrical block of a copper alloy and cooled by forced ventilation. In order to determine the energy density distribution deposited by the beam in the dump, Monte Carlo simulations were performed using FLUKA, and thermomechanical analyses carried out by importing the energy density into Ansys. In addition, CFD simulations of the airflow were carried out in order to accurately estimate the heat transfer convection coefficient on the surface of the dump. This paper describes the design process and highlights the constraints of integrating a new dump for increased beam power into the existing facility.

  6. Electromagnetic Coupling Between High Intensity LHC Beams and the Synchrotron Radiation Monitor Light Extraction System

    CERN Document Server

    Andreazza, W; Bravin, E; Caspers, F; Garlasch`e, M; Gras, J; Goldblatt, A; Lefevre, T; Jones, R; Metral, E; Nosych, A; Roncarolo_, F; Salvant, B; Trad, G; Veness, R; Vollinger, C; Wendt, M

    2013-01-01

    The CERN LHC is equipped with two Synchrotron Radiation Monitor (BSRT) systems used to characterise transverse and longitudinal beam distributions. Since the end of the 2011 LHC run the light extraction system, based on a retractable mirror, has suffered deformation and mechanical failure that is correlated to the increase in beam intensity. Temperature probes have associated these observations to a strong heating of the mirror support with a dependence on the longitudinal bunch length and shape, indicating the origin as electromagnetic coupling between the beam and the structure. This paper combines all this information with the aim of characterising and improving the system in view of its upgrade during the current LHC shutdown. Beam-based observations are presented along with electromagnetic and thermomechanical simulations and complemented by laboratory measurements, including the study of the RF properties of different mirror bulk and coating materials.

  7. Development of a high quality kicker magnet system

    International Nuclear Information System (INIS)

    Presently, there are 6 proton and 6 antiproton bunches used for collider operation in the Fermilab Tevatron. As the number of particles in these bunches increases, experimenter's detectors begin to saturate. To alleviate this situation, protons and antiprotons will be redistributed in 36 bunches instead of 6 to reduce the number of interactions per crossing. In order to carry this out, the rise and fall times of the Tevatron antiproton injection kicker which deflects the antiprotons onto the closed orbit must be reduced to accommodate the increased number of bunches circulating in the machine. To meet these criteria, it is necessary to reduce the inductance per unit length as seen by the driving source in order to achieve the necessary propagation time through the magnet, For a given aperture, this can be readily done using a picture frame design powered with two pulses of opposite polarity. Two magnets are required, each with a magnetic length of 2.41 m

  8. Fast and reliable kicker magnets for the SLC damping rings

    International Nuclear Information System (INIS)

    The design, construction, and operation of a kicker magnet with superior electromagnetic performance and greatly improved radiation tolerance is described. A short flux return of high mu ferrite improves the field strength and linearity with current, and novel metallic field-confining structures minimize the inductance. An 8-cell structure with capacitance integrated into each cell makes the magnet a nearly perfect transmission line. The capacitor dielectric is 1 cm thick alumina-loaded epoxy, processed to eliminate air voids, and cast in a multiple step procedure developed to circumvent epoxy shrinkage. The magnet operates with pulses of up to 40 kV and 3.2 kA at 120 Hz, with magnet transit times of less than 35 nsec and field rise and fall times of less than 60 nsec

  9. Fast and reliable kicker magnets for the SLC damping rings

    Energy Technology Data Exchange (ETDEWEB)

    Mattison, T.S.; Cassel, R.L.; Donaldson, A.R.; Gross, G.

    1995-06-01

    The design, construction, and operation of a kicker magnet with superior electromagnetic performance and greatly improved radiation tolerance is described. A short flux return of high mu ferrite improves the field strength and linearity with current, and novel metallic field-confining structures minimize the inductance. An 8-cell structure with capacitance integrated into each cell makes the magnet a nearly perfect transmission line. The capacitor dielectric is 1 cm thick alumina-loaded epoxy, processed to eliminate air voids, and cast in a multiple step procedure developed to circumvent epoxy shrinkage. The magnet operates with pulses of up to 40 kV and 3.2 kA at 120 Hz, with magnet transit times of less than 35 nsec and field rise and fall times of less than 60 nsec.

  10. Magnetic study of extraction elements of compact cyclotron beam with AGOR superconducting coils

    International Nuclear Information System (INIS)

    The extraction system of the superconducting cyclotrons is normally making a large use of electric extractors followed by magnetostatic elements. The electric field limit initially hoped for (14 MV/m) has been shown to be too optimistic. A more realistic value is around 10 MV/m in the concerned geometries. The first element of the AGOR extraction system is an electrostatic channel where the maximum electric field is limited to 10.5 MV/m. The smaller separation between the internal beam and the extracted beam at the entrance of the first magnetic element is compensated by the replacement of the usual magnetostatic channels with high power electromagnetic channels placed in the reduced space close to the internal beam and where the horizontal position can be adjusted according to the kind of ion accelerated and its energy. The fringing field very close to the channels is controlled with the help of correction coils reducing the perturbations of the internal beam trajectories to an acceptable level

  11. Beam extraction from a laser-driven multicharged ion source (abstract)

    International Nuclear Information System (INIS)

    A newly proposed type of multicharged ion source has several potential advantages over existing types and a number of useful applications. The basic principle is that multiphoton absorption in an intense uniform laser focus can give multiple charge states of high purity (Ref. 1). Thus, charge state separation downstream is simplified or made unnecessary. Another advantage is that large currents (hundreds of amperes) can be extracted. This type of source could be used for heavy-ion fusion drivers (see Ref. 1) or storage rings. There are also industrial application such as materials processing. We describe conceptual design studies for several specific cases. For example, we discuss extraction and focusing of a 4.1 MV, 144 A beam of Xe16+ ions from an expanding plasma created by an intense laser. The maximum duration of the beam pulse is determined by the total charge in the plasma, while the practical pulse length is determined by the range of plasma radii over which good beam optics can be achieved. The initially diverging beam can be refocused to a small radius or made parallel by a combination of electrostatic and solenoid focusing. Our design studies are carried out first with an envelope code to determine the proper focusing parameters and then with a self-consistent particle code to optimize the beam quality. We present results from both codes and discuss several applications of this type of ion source.copyright 1998 American Institute of Physics

  12. Beam extraction from a laser-driven multicharged ion source (abstract)

    Science.gov (United States)

    Anderson, O. A.; Logan, B. Grant

    1998-02-01

    A newly proposed type of multicharged ion source has several potential advantages over existing types and a number of useful applications. The basic principle is that multiphoton absorption in an intense uniform laser focus can give multiple charge states of high purity (Ref. Reference 1). Thus, charge state separation downstream is simplified or made unnecessary. Another advantage is that large currents (hundreds of amperes) can be extracted. This type of source could be used for heavy-ion fusion drivers (see Ref. Reference 1) or storage rings. There are also industrial application such as materials processing. We describe conceptual design studies for several specific cases. For example, we discuss extraction and focusing of a 4.1 MV, 144 A beam of Xe16+ ions from an expanding plasma created by an intense laser. The maximum duration of the beam pulse is determined by the total charge in the plasma, while the practical pulse length is determined by the range of plasma radii over which good beam optics can be achieved. The initially diverging beam can be refocused to a small radius or made parallel by a combination of electrostatic and solenoid focusing. Our design studies are carried out first with an envelope code to determine the proper focusing parameters and then with a self-consistent particle code to optimize the beam quality. We present results from both codes and discuss several applications of this type of ion source.

  13. Kinetic plasma simulation of ion beam extraction from an ECR ion source

    International Nuclear Information System (INIS)

    Designing optimized ECR (electron cyclotron resonance) ion beam sources can be streamlined by the accurate simulation of beam optical properties in order to predict ion extraction behavior. The complexity of these models, however, can make PIC-based simulations time-consuming. In this paper, we first describe a simple kinetic plasma finite element simulation of extraction of a proton beam from a permanent magnet hexapole ECR ion source. Second, we analyze the influence of secondary electrons generated by ion collisions in the residual gas on the space charge of a proton beam of a dual-solenoid ECR ion source. The finite element method (FEM) offers a fast modeling environment, allowing analysis of ion beam behavior under conditions of varying current density, electrode potential, and gas pressure. The new version of SCALA/TOSCA v14 permits the making of simulations in tens of minutes to a few hours on standard computer platforms without the need of particle-in-cell methods. The paper is followed by the slides of the presentation. (authors)

  14. Studies of beam injection with a compensated bump and uncompensated bump in a synchrotron

    International Nuclear Information System (INIS)

    Synchrotron radiation sources Indus-1 and Indus-2 have a synchrotron as the common injector. A three kicker compensated bump injection scheme was employed for beam injection into this synchrotron. The stored beam current in the synchrotron is higher, when all the three kickers are operated at the same current than when kickers are operated at currents required to generate compensated bump. Beam dynamics studies have been done to understand why this happens. Theoretical studies indicate that higher stored current in the later case is attributed to smaller residual oscillations of injected beam. These studies also reveal that if the angle of the injected beam during beam injection is kept varying, the performance could be further improved. This is experimentally confirmed by injecting the beam on rising part of the injection septum magnet current pulse

  15. Studies of beam injection with a compensated bump and uncompensated bump in a synchrotron

    Energy Technology Data Exchange (ETDEWEB)

    Akbar Fakhri, Ali; Prajapati, S. K.; Ghodke, A. D.; Singh, Gurnam [Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)

    2013-08-15

    Synchrotron radiation sources Indus-1 and Indus-2 have a synchrotron as the common injector. A three kicker compensated bump injection scheme was employed for beam injection into this synchrotron. The stored beam current in the synchrotron is higher, when all the three kickers are operated at the same current than when kickers are operated at currents required to generate compensated bump. Beam dynamics studies have been done to understand why this happens. Theoretical studies indicate that higher stored current in the later case is attributed to smaller residual oscillations of injected beam. These studies also reveal that if the angle of the injected beam during beam injection is kept varying, the performance could be further improved. This is experimentally confirmed by injecting the beam on rising part of the injection septum magnet current pulse.

  16. Enhancement of beam pulse controllability for a single-pulse formation system of a cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Kurashima, Satoshi, E-mail: kurashima.satoshi@jaea.go.jp; Miyawaki, Nobumasa; Kashiwagi, Hirotsugu; Okumura, Susumu [Takasaki Advanced Radiation Research Institute, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Taguchi, Mitsumasa [Quantum Beam Science Center, Japan Atomic Energy Agency, 1233 Watanuki, Takasaki, Gunma 370-1292 (Japan); Fukuda, Mitsuhiro [Research Center for Nuclear Physics, Osaka University, 10-1 Mihogaoka, Ibaraki, Osaka 567-0047 (Japan)

    2015-07-15

    The single-pulse formation technique using a beam chopping system consisting of two types of high-voltage beam kickers was improved to enhance the quality and intensity of the single-pulse beam with a pulse interval over 1 μs at the Japan Atomic Energy Agency cyclotron facility. A contamination rate of neighboring beam bunches in the single-pulse beam was reduced to less than 0.1%. Long-term purification of the single pulse beam was guaranteed by the well-controlled magnetic field stabilization system for the cyclotron magnet. Reduction of the multi-turn extraction number for suppressing the neighboring beam bunch contamination was achieved by restriction of a beam phase width and precise optimization of a particle acceleration phase. In addition, the single-pulse beam intensity was increased by a factor of two or more by a combination of two types of beam bunchers using sinusoidal and saw-tooth voltage waveforms. Provision of the high quality intense single-pulse beam contributed to improve the accuracy of experiments for investigation of scintillation light time-profile and for neutron energy measurement by a time-of-flight method.

  17. Enhancement of beam pulse controllability for a single-pulse formation system of a cyclotron

    International Nuclear Information System (INIS)

    The single-pulse formation technique using a beam chopping system consisting of two types of high-voltage beam kickers was improved to enhance the quality and intensity of the single-pulse beam with a pulse interval over 1 μs at the Japan Atomic Energy Agency cyclotron facility. A contamination rate of neighboring beam bunches in the single-pulse beam was reduced to less than 0.1%. Long-term purification of the single pulse beam was guaranteed by the well-controlled magnetic field stabilization system for the cyclotron magnet. Reduction of the multi-turn extraction number for suppressing the neighboring beam bunch contamination was achieved by restriction of a beam phase width and precise optimization of a particle acceleration phase. In addition, the single-pulse beam intensity was increased by a factor of two or more by a combination of two types of beam bunchers using sinusoidal and saw-tooth voltage waveforms. Provision of the high quality intense single-pulse beam contributed to improve the accuracy of experiments for investigation of scintillation light time-profile and for neutron energy measurement by a time-of-flight method

  18. Long pulse H- beam extraction with a rf driven ion source on a high power level

    International Nuclear Information System (INIS)

    IPP Garching is investigating the applicability of rf driven negative ion sources for the neutral beam injection of International Thermonuclear Experimental Reactor. The setup of the tested source was improved to enable long pulses up to 100 kW rf power. The efficiency of negative ion production decreases at high power. The extracted H- currents as well as the symmetry of the plasma density close to the plasma grid and of the beam divergence depend on the magnetic filter field. The pulse duration is limited by the increase in coextracted electrons, which depends on the rf power and the caesium conditions on the plasma grid.

  19. Effect of electron-beam irradiation on the antioxidant activity of extracts from Citrus unshiu pomaces

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong-Wan [Department of Food Science and Biotechnology, Kyungnam University, Masan 631-701 (Korea, Republic of); Lee, Byung Cheol [Laboratory for Quantum Optics, Korea Atomic Energy Research Institute, Daejeon 305-600 (Korea, Republic of); Lee, Jong-Hwa [School of Bioresource Sciences, Andong National University, Andong 760-749 (Korea, Republic of); Nam, Ki-Chang [Chemistry and Biotechnology Examinations Bureau, Korean Intellectual Property Office, Daejeon 302-701 (Korea, Republic of); Lee, Seung-Cheol [Department of Food Science and Biotechnology, Kyungnam University, Masan 631-701 (Korea, Republic of)], E-mail: sclee@kyungnam.ac.kr

    2008-01-15

    After electron-beam irradiation of citrus pomaces (CP), the total phenolic content (TPC), radical scavenging activity (RSA), and reducing power (RP) were evaluated. When CP were irradiated at 37.9 kGy; the TPC, RSA and RP of water extract of CP increased from 6543.2 to 7405.4 {mu}M, 37.6% to 52.9%, and 0.64 to 0.90, respectively, compared with the non-irradiated control. The results indicate that the electron-beam irradiation can be an efficient process for increasing the antioxidant activity of CP.

  20. Model and analysis of eddy current of ferrite-dominated kicker magnet in Hefei light source ring

    International Nuclear Information System (INIS)

    The ferrite-dominated kicker magnet whose main function is to produce uniform pulsed magnetic field is one of the crucial elements in injection-system improvement task of national synchrotron radiation lab phase II project. The mathematical model and analysis concerned in eddy current of kicker's core in the designing is presented. The result of quantitative analysis demonstrates that, to determine the conductivity of ferrite material and parameters of magnetic core reasonably can eliminate the effects of eddy current on the magnetic-field properties. The results of pulsed-magnetic-field measurement of kicker magnets show that, the design of kicker magnets of HLS storage ring is reasonable

  1. SIMULATION OF NEUTRON BACKGROUNDS FROM THE ILC EXTRACTION LINE BEAM DUMP

    Energy Technology Data Exchange (ETDEWEB)

    Darbha, S; Keller, L.; Maruyama, T.

    2008-01-01

    The operation of the International Linear Collider (ILC) as a precision measurement machine is dependent upon the quality of the charge-coupled device (CCD) silicon vertex detector. An integrated fl ux of 1010 neutrons/cm2 incident upon the vertex detector will degrade its performance by causing displacement damage in the silicon. One source of the neutron background arises from the dumping of the spent electron and positron beams into the extraction line beam dumps. The Monte Carlo program FLUKA was used to simulate the collision of the electron beam with the dump and to determine the resulting neutron fl ux at the interaction point (IP). A collimator and tunnel were added and their effect on the fl ux was analyzed. A neutron source was then generated and directed along the extraction line towards a model of the vertex detector to determine the neutron fl ux in its silicon layers. Models of the beampipe and BeamCal, a silicon-tungsten electromagnetic calorimeter in the very forward region of the detector, were placed in the extraction line and their effects on scattering were studied. The IP fl uence was determined to be 3.7x1010 +/- 2.3x1010 neutrons/cm2/year when the tunnel and collimator were in place, with no appreciable increase in statistics when the tunnel was removed. The BeamCal was discovered to act as a collimator by signifi cantly impeding the fl ow of neutrons towards the detector. The majority of damage done to the fi rst layer of the detector was found to come from neutrons with a direct line of sight from the fi rst extraction line quadrupole QDEX1, with only a small fraction scattering off of the beampipe and into the detector. The 1 MeV equivalent neutron fl uence was determined to be 9.3x108 neutrons/cm2/year from the electron beam alone. The two beams collectively contribute double to this fl uence, which is 19% of the threshold value in one year. Future work will improve the detector model and other sources of neutron backgrounds will be

  2. Simulation of the CERN GTS-LHC ECR ion source extraction system with lead and argon ion beams

    CERN Document Server

    Toivanen, V; Küchler, D; Lombardi, A; Scrivens, R; Stafford-Haworth, J

    2014-01-01

    A comprehensive study of beam formation and beam transport has been initiated in order to improve the performance of the CERN heavy ion injector, Linac3. As part of this study, the ion beam extraction system of the CERN GTS-LHC 14.5 GHz Electron Cyclotron Resonance Ion Source (ECRIS) has been modelled with the ion optical code IBSimu. The simulations predict self-consistently the triangular and hollow beam structures which are often observed experimentally with ECRIS ion beams. The model is used to investigate the performance of the current extraction system and provides a basis for possible future improvements. In addition, the extraction simulation provides a more realistic representation of the initial beam properties for the beam transport simulations, which aim to identify the performance bottle necks along the Linac3 low energy beam transport. The results of beam extraction simulations with Pb and Ar ion beams from the GTS-LHC will be presented and compared with experimental observations.

  3. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source

    Energy Technology Data Exchange (ETDEWEB)

    Roychowdhury, P., E-mail: pradipr@barc.gov.in; Mishra, L.; Kewlani, H.; Mittal, K. C. [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Patil, D. S. [Laser and Plasma Technology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

    2014-03-15

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20–40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, −2 to −4 kV, and 0 kV, respectively. The total ion beam current of 30–40 mA is recorded on Faraday cup at 40 keV of beam energy at 600–1000 W of microwave power, 800–1000 G axial magnetic field and (1.2–3.9) × 10{sup −3} mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source.

  4. Beam extraction and high stability operation of high current electron cyclotron resonance proton ion source

    International Nuclear Information System (INIS)

    A high current electron cyclotron resonance proton ion source is designed and developed for the low energy high intensity proton accelerator at Bhabha Atomic Research Centre. The plasma discharge in the ion source is stabilized by minimizing the reflected microwave power using four stub auto tuner and magnetic field. The optimization of extraction geometry is performed using PBGUNS code by varying the aperture, shape, accelerating gap, and the potential on the electrodes. While operating the source, it was found that the two layered microwave window (6 mm quartz plate and 2 mm boron nitride plate) was damaged (a fine hole was drilled) by the back-streaming electrons after continuous operation of the source for 3 h at beam current of 20–40 mA. The microwave window was then shifted from the line of sight of the back-streaming electrons and located after the water-cooled H-plane bend. In this configuration the stable operation of the high current ion source for several hours is achieved. The ion beam is extracted from the source by biasing plasma electrode, puller electrode, and ground electrode to +10 to +50 kV, −2 to −4 kV, and 0 kV, respectively. The total ion beam current of 30–40 mA is recorded on Faraday cup at 40 keV of beam energy at 600–1000 W of microwave power, 800–1000 G axial magnetic field and (1.2–3.9) × 10−3 mbar of neutral hydrogen gas pressure in the plasma chamber. The dependence of beam current on extraction voltage, microwave power, and gas pressure is investigated in the range of operation of the ion source

  5. Beam extractions of a prototype long pulse ion source for the KSTAR NBI system

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Doo Hee; Seo, Chang Seok; Jun, Yong Woo; Oh, Byung Hoon; Jeong, Seung Ho; Lee, Kwang Won; In, Sang Ryul; Kim, Jin Choon [KAERI, Taejon (Korea, Republic of)

    2003-10-01

    Preliminary beam extraction experiments of a prototype long pulse (300 s) ion source were carried out on the NBI Test Stand for the KSTAR. The prototype ion source consists of a magnet bucket plasma generator with multi-pole cusp fields, similar to the US LPIS, and a set of tetrode accelerator with circular apertures. Arc discharges of the plasma generator have been controlled precisely by both a space-charge-limited mode and an emission-limited mode. The emission-limited operation, well controlled by the applied heating voltage of cathode filaments, of plasma generator resulted in more efficient and stable discharges than the space-charge- limited mode. An optimum arc efficiency of 0.33 A/kW and maximum ion density of 8310{sup 11} cm{sup -3} were obtained by using a Langmuir probe. Optimum beam perveance of the prototype ion source, which was deduced from the ratio of gradient grid current to the beam current, was 0.52. The preliminary beam extraction results obtained at {<=} 41 kV appear less than the expected.

  6. Neutron optical imaging study of neutron moderator and beam extraction system

    Energy Technology Data Exchange (ETDEWEB)

    Fuezi, J. [Research Institute for Solid State Physics and Optics, H-1525 Budapest (Hungary) and Transilvania University, R-2200 Brasov (Romania)]. E-mail: fuzi@szfki.hu; David, E. [OPEN Optoelectronics, 1121 Budapest (Hungary); Kozlowski, T. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Lewis, P. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Messing, G. [OPEN Optoelectronics, 1121 Budapest(Hungary); Mezei, F. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Hahn-Meitner-Institut, 14109 Berlin (Germany); Penttila, S. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Rosta, L. [Research Institute for Solid State Physics and Optics, H-1525 Budapest (Hungary); Russina, M. [Hahn-Meitner-Institut, 14109 Berlin (Germany); Toeroek, Gy. [Research Institute for Solid State Physics and Optics, H-1525 Budapest (Hungary)

    2006-11-15

    The study of the performance of a cold-hydrogen moderator and a supermirror-based neutron beam extraction system of the flight path 12 at LANSCE has been performed based on energy-resolved neutron optical imaging. We have developed a pinhole camera system with a 2D position-sensitive {sup 3}He multiwire proportional chamber neutron detector with delay line position encoding (0.75 mm pixel size), together with a standalone time-of-flight electronic system with 1.2 {mu}s dead time. We have determined the efficiency, resolution, and counting rate saturation of the detector. In particular, we have considered an impact of these parameters on the quality of the images. The neutron images of the moderator were taken as a function of the neutron wavelength given by the time-of-flight information. The images were recorded as arrays of 256x256x2000 pixels; x and y coordinates, and time of flight. Information obtained from the images includes a distribution of the brightness on the neutron moderator, the efficiency and geometrical accuracy of the beam extraction system, and the reflectivity of the supermirror-coated elements of its optics. Our results demonstrate that the pinhole optical camera-based neutron imaging method combined with time-of-flight information is an extremely efficient tool to characterize neutron sources and neutron beam extraction systems.

  7. Demonstration of large electron-beam energy extraction by a tapered-wiggler free-electron laser

    International Nuclear Information System (INIS)

    Electron-beam energy spectral measurements were made on a tapered-wiggler free-electron laser amplifier. A 10 MeV electron beam from a traveling-wave linear accelerator interacted in a tapered-wiggler with an intense 10.6μm CO/sub 2/ laser beam. The electron spectra show a 4 percent net energy loss and a 9 percent peak loss. Measurements of electron energy spectra, extraction efficiency as a function of electron-beam energy, and extraction efficiency as a function of optical power are presented and are consistent with theoretically predicted performance

  8. Multiturn septum magnets for proton beam extraction from the IHEP accelerator

    International Nuclear Information System (INIS)

    Structure of multiturn septum magnet for he systems of proton beam extraction from the IHEP accelerator is described. Excitation coil, magnet core and all communications are located outside the accelerator vacuum volume. The magnet is characterized by a low gas release to the vacuum volume under the residual gas pressures of up to 1x10 -8Pa. The transition from monoturn excitation coil to multiturn one allowed one to decrease the value of necessary current and thus to reduce the energy loss in the bus duct from the power supply source to septum magnet. This allows one to increase the duration of slow proton extraction under the same power consumption. For example, after transition to two- and four-turn septum magnets the slow extraction duration can be increased up to two seconds, i.e.-doubled, which opens up a possibility to organize the particle beam extraction along two separate transport channels. By the present time the septum magnet has made 300000 cycles within the framework of physical experiments

  9. Maxillary sinus pneumatization after maxillary molar extraction assessed with cone beam computed tomography

    International Nuclear Information System (INIS)

    The purpose of this study was to examine the inferior expansion of the maxillary sinus floor following maxillary molar extraction. Cone beam computed tomographic images of 59 subjects were used to evaluate the height difference of the maxillary sinus floor between extraction sites and contralateral dentate sites. The height of the maxillary sinus floor was defined as the vertical distance to the Frankfort plane from the level of the anterior nasal spine to the most inferior point of the sinus floor. We examined the difference in sinus pneumatization according to the number of missing teeth and the vertical relationship of the molar roots to the sinus floor. The inferior expansion of the maxillary sinus floor was 1.20 ± 1.86 mm on the maxillary first molar and 1.90 ± 2.42 mm on the maxillary second molar. Increased expansion was observed in cases where two proximate molars were extracted. There was no significant difference in sinus pneumatization following extraction according to the vertical relationship of the molar roots to the sinus floor. The results of this study confirm that sinus pneumatization occurs following maxillary molar extraction. In situations where pneumatization can affect treatment after molar extraction, three-dimensional radiography should be considered.

  10. Accidental beam loss in superconducting accelerators: Simulations, consequences of accidents and protective measures

    International Nuclear Information System (INIS)

    The consequences of an accidental beam loss in superconducting accelerators and colliders of the next generation range from the mundane to rather dramatic, i.e., from superconducting magnet quench, to overheating of critical components, to a total destruction of some units via explosion. Specific measures are required to minimize and eliminate such events as much as practical. In this paper we study such accidents taking the Superconducting Supercollider complex as an example. Particle tracking, beam loss and energy deposition calculations were done using the realistic machine simulation with the Monte-Carlo codes MARS 12 and STRUCT. Protective measures for minimizing the damaging effects of prefire and misfire of injection and extraction kicker magnets are proposed here

  11. Upgrading of the SPS injection kicker system for LHC requirements

    CERN Document Server

    Ducimetière, L; Uythoven, J; Vossenberg, Eugène B; Han, Q

    1998-01-01

    The present SPS injection kicker system is composed of 12 travelling wave magnets connected in pairs to six pulse generators. The eight most upstream magnets ('S'-type) have a kick rise time (2-98%) o f 145 ns and the remaining four ('L'-type) of 215 ns. The flat top ripple of the kick is ±1%. In the future, this system will also inject protons and ions for the LHC, with a bunch spacing of respect ively 220 ns and 125 ns, and a flat top ripple requirement of at most ±0.5%. Important modifications, concerning both magnets and generators, are then required to meet these goals. For ion injection only 'S'-type magnets will be used. The reduction of the kick rise time will be achieved by shortening the magnet length and increasing the characteristic impedance. To compensate for the loss in tota l kick strength, four new magnets and two new pulse generators will be added. At the moment it is not intended to modify the 'L'-type magnets. Most of the pulse forming networks (PFN's) must be adapt ed to the higher char...

  12. Simulated Beam Extraction Performance Characterization of a 50-cm Ion Thruster Discharge

    Science.gov (United States)

    Foster, John E.; Hubble, Aimee; Nowak-Gucker, Sarah; Davis, Chris; Peterson, Peter; Viges, Eric; Chen, Dave

    2013-01-01

    A 50 cm ion thruster is being developed to operate at >65 percent total efficiency at 11 kW, 2700 s Isp and over 25 kW, 4500 s Isp at a total efficiency of >75 percent. The engine is being developed to address the need for a multimode system that can provide a range of thrust-to- power to service national and commercial near-earth onboard propulsion needs such as station-keeping and orbit transfer. Operating characteristics of the 50 cm ion thruster were measured under simulated beam extraction. The discharge current distribution at the various magnet rings was measured over a range of operating conditions. The relationship between the anode current distribution and the resulting plasma uniformity and ion flux measured at the thruster exit plane is discussed. The thermal envelope will also be investigated through the monitoring of magnet temperatures over the range of discharge powers investigated. Discharge losses as a function of propellant utilization was also characterized at multiple simulated beam currents. Bulk plasma conditions such as electron temperature and electron density near engine centerline was measured over a range of operating conditions using an internal Langmuir probe. Sensitivity of discharge performance to chamber length is also discussed. This data acquired from this discharge study will be used in the refinement of a throttle table in anticipation for eventual beam extraction testing.

  13. High current precision long pulse electron beam position monitor

    CERN Document Server

    Nelson, S D; Fessenden, T J; Holmes, C

    2000-01-01

    Precision high current long pulse electron beam position monitoring has typically experienced problems with high Q sensors, sensors damped to the point of lack of precision, or sensors that interact substantially with any beam halo thus obscuring the desired signal. As part of the effort to develop a multi-axis electron beam transport system using transverse electromagnetic stripline kicker technology, it is necessary to precisely determine the position and extent of long high energy beams for accurate beam position control (6 - 40 MeV, 1 - 4 kA, 2 μs beam pulse, sub millimeter beam position accuracy.) The kicker positioning system utilizes shot-to-shot adjustments for reduction of relatively slow (< 20 MHz) motion of the beam centroid. The electron beams passing through the diagnostic systems have the potential for large halo effects that tend to corrupt position measurements.

  14. Bi-spectral beam extraction in combination with a focusing feeder

    CERN Document Server

    Zendler, C; Nekrassov, D; Cussen, L D; Strobl, M

    2013-01-01

    Bi-spectral beam extraction combines neutrons from two different kind of moderators into one beamline, expanding the spectral range and thereby the utilization of an instrument. This idea can be realized by a mirror that reflects long wavelength neutrons from an off-axis colder moderator into a neutron guide aligned with another moderator emitting neutrons with shorter wavelengths which will be transmitted through the mirror. The mirror used in such systems is typically several meters long, which is a severe disadvantage because it reduces the possible length of a focusing device in design concepts requiring a narrow beam at a short distance from the source, as used in many instruments under development for the planned European Spallation Source (ESS). We propose a shortened extraction system consisting of several mirrors, and show that such an extraction system is better suited for combination with a feeder in an eye of the needle design, illustrated here in the context of a possible ESS imaging beamline.

  15. Bi-spectral beam extraction in combination with a focusing feeder

    Energy Technology Data Exchange (ETDEWEB)

    Zendler, C., E-mail: carolin.zendler@helmholtz-berlin.de [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); ESS Design Update Programme (Germany); Lieutenant, K.; Nekrassov, D.; Cussen, L.D. [Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); ESS Design Update Programme (Germany); Strobl, M. [European Spallation Source ESS AB, Box 176, 22100 Lund (Sweden)

    2013-03-11

    Bi-spectral beam extraction combines neutrons from two different kinds of moderators into one beamline, expanding the spectral range and thereby the utilization of an instrument. This idea can be realized by a mirror that reflects long wavelength neutrons from an off-axis colder moderator into a neutron guide aligned with another moderator emitting neutrons with shorter wavelengths which will be transmitted through the mirror. The mirror used in such systems is typically several meters long, which is a severe disadvantage because it reduces the possible length of a focusing device in design concepts requiring a narrow beam at a short distance from the source, as used in many instruments under development for the planned European Spallation Source (ESS). We propose a shortened extraction system consisting of several mirrors and show that such an extraction system is better suited for combination with a feeder in an eye of the needle design, illustrated here in the context of a possible ESS imaging beamline.

  16. Protective effect of allium sativum ethanol extract on cultured human lymphocytes against electron beam radiation

    International Nuclear Information System (INIS)

    The development of radioprotective agent has been the subject of intense research because exposure to ionizing radiation causes DNA damage which may cause mutation and ultimately leads to cancer, on the other hand radiotherapy has become an integral part in treatment of cancer which uses ionizing radiations like X rays, gamma rays to kill the cancer cells. Amifostine is a well-known radioprotector which is clinically approved. There are many other radioprotectors like cysteine, cystamine, serotine but they are not used because of its normal tissue toxicity. Allium sativum is commonly known as garlic which has already been reported for its medicinal properties. In this study we evaluated radioprotection property of Allium sativum on DNA damage caused by electron beam radiation in cultured human lymphocytes. Allium sativum ethanol extract was used for this study. Cell viability was performed by MTT assay. DNA damage was assessed by comet assay parameters. The cultured lymphocytes were incubated with different concentrations 10, 50 and 100 μg/mL of Allium sativum extracts for 2, 4, 6 and 24 hour time intervals. Treatment of lymphocytes with various concentration of Allium sativum extract resulted in significant decrease in the level of DNA damage (Percentage tail DNA 6%) and increase in cell viability 93% (p>0.05) compare to the radiation control group. Results of this study revealed that Allium sativum protects cultured lymphocytes when exposed to electron beam radiation at its sub lethal dose. (author)

  17. Structure and organization of automation subsystem for control of beam extraction from a fast-cycling synchrotron

    International Nuclear Information System (INIS)

    The status of development of an automation subsystem for control of beam extraction from the Erevan synchrotron is described. The hardware complex of the subsystem contains the RPT-80 microcomputer, seven units of automated control for the beam extraction channel, a timer unit for synchronization of the accelerator output devices, a unit for monitoring status signals, an ADS, an interface with the synchrotron, a commutation line between RPT80 and the host ES1010 computer. As a result pilot operation the beam energy spread instability has been reduced 15 times. 5 refs.; 1 fig

  18. Achievement of very low jitter extraction of high power proton beams in the J-PARC RCS

    International Nuclear Information System (INIS)

    The 3 GeV rapid cycling synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) delivers high intensity proton beams to the Materials and Life Science Facility (MLF) and the main ring (MR). The repetition rate of the RCS is 25 Hz. The typical operation period of the J-PARC is 3.2 s, which consists of 80 RCS cycles. Four beam pulses are for the MR and the other pulses are led into the MLF. Since a bucket-to-bucket injection scheme is used for the MR, the beam from the RCS must be injected with a precise phase to the proper rf bucket of the MR. In case of the MLF, the beam has to be synchronized to the Fermi chopper, which has a tolerance of only a few 100 ns. Thus, stable beam timings with a very low jitter are required for both destinations. To realize the stable beam timing, we employ the timing system, which is not synchronized to the AC power line. Also the magnetic-alloy accelerating cavities and the full digital low-level RF control system are the keys for the precise beam phase control. For acceleration of a high power beam, the phase feedback loop, which damps the longitudinal dipole oscillation, is necessary. The phase loop is a cause of the jitter of the beam extraction timing. We apply a gain pattern of the phase loop to avoid the influence on the beam phase at the extraction. We have achieved a very low jitter extraction of a high power beam within 1.7 ns, which corresponds to 1 degree of the rf frequency at the extraction.

  19. Achievement of very low jitter extraction of high power proton beams in the J-PARC RCS

    Science.gov (United States)

    Tamura, Fumihiko; Yoshii, Masahito; Schnase, Alexander; Ohmori, Chihiro; Yamamoto, Masanobu; Nomura, Masahiro; Toda, Makoto; Shimada, Taihei; Hara, Keigo; Hasegawa, Katsushi

    2011-08-01

    The 3 GeV rapid cycling synchrotron (RCS) of the Japan Proton Accelerator Research Complex (J-PARC) delivers high intensity proton beams to the Materials and Life Science Facility (MLF) and the main ring (MR). The repetition rate of the RCS is 25 Hz. The typical operation period of the J-PARC is 3.2 s, which consists of 80 RCS cycles. Four beam pulses are for the MR and the other pulses are led into the MLF. Since a bucket-to-bucket injection scheme is used for the MR, the beam from the RCS must be injected with a precise phase to the proper rf bucket of the MR. In case of the MLF, the beam has to be synchronized to the Fermi chopper, which has a tolerance of only a few 100 ns. Thus, stable beam timings with a very low jitter are required for both destinations. To realize the stable beam timing, we employ the timing system, which is not synchronized to the AC power line. Also the magnetic-alloy accelerating cavities and the full digital low-level RF control system are the keys for the precise beam phase control. For acceleration of a high power beam, the phase feedback loop, which damps the longitudinal dipole oscillation, is necessary. The phase loop is a cause of the jitter of the beam extraction timing. We apply a gain pattern of the phase loop to avoid the influence on the beam phase at the extraction. We have achieved a very low jitter extraction of a high power beam within 1.7 ns, which corresponds to 1 degree of the rf frequency at the extraction.

  20. Dipole magnet and quadrupole lens for the slow extraction of a beam from the Dubna synchrophasotron

    International Nuclear Information System (INIS)

    The deflection system for the second slow extraction (SE-2) of a beam of protons and nuclei from the Dubna synchrophasotron consists of a dipole septum-magnet (VM-2) and a quadrupole septum-lens (VL-2). The magnet, the lens, the current conductors for supplying their windings and the driver used for the SE-2 system are described. A general scheme of cooling the windings of the magnet, lens and conductors is presented. The magnetic characteristics of the VM-2 magnet and the VL-2 lens are given. The system used to control the parameters of the SE-2 is described. 4 refs.; 16 figs

  1. Preliminary Simulation of Beam Extraction for the 28 GHz ECR Ion Source

    OpenAIRE

    Park, Bum-Sik; Kim, Yonghwan; Choi, Seokjin

    2015-01-01

    The 28 GHz ECR(Electron Cyclotron Resonance) ion source is under development to supply various beams from proton to uranium at RISP(Rare Isotope Science Project). The superconducting magnet system for a 28 GHz ECR ion source consists of four solenoid coils and a saddle type sextupole. To meet the design requirement of ECR ion source, a numerical simulation was accomplished by using the KOBRA3-INP to optimize the extraction system which is the three dimensional ion optics code. The influence o...

  2. One of the 10 cells of AA Injection Kicker K4

    CERN Multimedia

    1979-01-01

    The 3.5 GeV/c Antiproton Accumulator (AA) had 2 delay-line type injection kickers, K3 (12 cells) and K4 (10 cells). Here we see one of the K4 cells, with ferrite between stainless-steel plates. Pulse voltage: 61 kV; rise/fall-time 86 ns; flat-top 460 ns; top flatness +-2%. During injection, the open side of the C-shaped kickers was closed off with a fast shutter, so that their stray field would not perturb the stack of already accumulated antiprotons.

  3. A study on the effects of electron beam irradiation on tooth extraction wound healing in rats

    International Nuclear Information System (INIS)

    The wound of the upper jaw 3 days after the first molar tooth extraction in female rats was exposed to 1,500 rads (Group 2) and 2,000 rads (Group 3) of the 10 MeV electron beams, and its pathohistological changes were compared with those of rats with the tooth extraction alone (control group). In the control group, the tooth extraction wound was covered with epithelium 10 days later and new bones were formed 17 days later. Wound healing with the epithelium was seen in all irradiated rats 24 days later. The formation of the new teeth was seen 24 days later in the Group 2 and 38 days later in Group 3. Cell infiltration under the epithelial layers was still observed in some of the Group 3, although the wound was covered with epithelium, and the new bone covering the extraction wound was formed 38 days later. Healing was prolonged in Group 3, as compared with that in Group 2. (Namekawa, K.)

  4. Ion beams extraction and measurements of plasma parameters on a multi-frequencies microwaves large bore ECRIS with permanent magnets

    International Nuclear Information System (INIS)

    We have developed an all-permanent magnet large bore electron cyclotron resonance ion source (ECRIS) for broad ion beam processing. The cylindrically comb-shaped magnetic field configuration is adopted for efficient plasma production and good magnetic confinement. To compensate for disadvantages of fixed magnetic configuration, a traveling wave tube amplifier (TWTA) is used. In the comb-shaped ECRIS, it is difficult to achieve controlling ion beam profiles in the whole inside the chamber by using even single frequency-controllable TWTA (11-13GHz), because of large bore size with all-magnets. We have tried controlling profiles of plasma parameters and then those of extracted ion beams by launching two largely different frequencies simultaneously, i.e., multi-frequencies microwaves. Here we report ion beam profiles and corresponding plasma parameters under various experimental conditions, dependence of ion beams against extraction voltages, and influence of different electrode positions on the electron density profile.

  5. Learning of Soccer Player Agents Using a Policy Gradient Method : Coordination Between Kicker and Receiver During Free Kicks

    Directory of Open Access Journals (Sweden)

    Harukazu Igarashi

    2011-04-01

    Full Text Available As an example of multi-agent learning in soccer games of the RoboCup 2D Soccer Simulation League, we dealt with a learning problem between a kicker and a receiver when a direct free kick is awarded just outside the opponent's penalty area. We propose how to use a heuristic function to evaluate an advantageous target point for safely sending/receiving a pass and scoring. The heuristics include an interaction term between a kicker and a receiver to intensify their coordination. To calculate the interaction term, we let a kicker/receiver agent have a receiver's/kicker's action decision model to predict a receiver's/kicker's action. Parameters in the heuristic function can be learned by a kind of reinforcement learning called the policy gradient method. Our experiments show that if the two agents do not have the same type of heuristics, the interaction term based on prediction of a teammate's decision model leads to learning a master-servant relation between a kicker and a receiver, where a receiver is a master and a kicker is a servant.

  6. Design of the extraction arc for the 2{sup nd} beam line of the free-electron laser FLASH

    Energy Technology Data Exchange (ETDEWEB)

    Scholz, Matthias

    2014-01-15

    In this thesis, I deal with the design of the extraction arc for the second beam line of FLASH, an FEL (Free-Electron Laser) user facility at DESY Hamburg. Both beam lines will use the same linear accelerator and their separation will take place behind the last accelerating module. I present the constraints for the extraction arc given by the beam line layout of the existing machine, by the building environment of the new beam line and in particular, by coherent synchrotron radiation (CSR). The impact from CSR is presented, and I show how to mitigate these effects and what that means for the beam line design. The optimization of the extraction arc was done applying the downhill simplex algorithm which is presented, first in its basic form to explain the operation principle and then in a more advanced version as used in the applied program. I introduce in this thesis the final layout of the extraction arc including the following matching section. This layout fulfills all given constraints and can provide the required electron beam quality for FEL operation. In order to prove this, I present start-to-end simulations for different bunch charges and for two different wavelengths.

  7. Design of the extraction arc for the 2nd beam line of the free-electron laser FLASH

    International Nuclear Information System (INIS)

    In this thesis, I deal with the design of the extraction arc for the second beam line of FLASH, an FEL (Free-Electron Laser) user facility at DESY Hamburg. Both beam lines will use the same linear accelerator and their separation will take place behind the last accelerating module. I present the constraints for the extraction arc given by the beam line layout of the existing machine, by the building environment of the new beam line and in particular, by coherent synchrotron radiation (CSR). The impact from CSR is presented, and I show how to mitigate these effects and what that means for the beam line design. The optimization of the extraction arc was done applying the downhill simplex algorithm which is presented, first in its basic form to explain the operation principle and then in a more advanced version as used in the applied program. I introduce in this thesis the final layout of the extraction arc including the following matching section. This layout fulfills all given constraints and can provide the required electron beam quality for FEL operation. In order to prove this, I present start-to-end simulations for different bunch charges and for two different wavelengths.

  8. Transverse beam splitting made operational: Recent progress of the multi-turn extraction at the CERN proton synchrotron

    CERN Document Server

    AUTHOR|(CDS)2082016; Borburgh, Jan; Damjanovic, Sanja; Gilardoni, Simone; Giovannozzi, Massimo; Hourican, Michael; Kahle, Karsten; Michels, Olivier; Sterbini, Guido; Hernalsteens, Cedric; Le Godec, Gilles

    2016-01-01

    Following a successful commissioning period, the Multi-Turn Extraction (MTE) at the CERN Proton Synchrotron (PS) has been applied for the fixed-target physics programme at the Super Proton Synchrotron (SPS) since September 2015. This exceptional extraction technique was proposed to replace the long-serving Continuous Transfer (CT) extraction, which has the drawback of inducing high activation in the ring. MTE exploits the principles of non-linear beam dynamics to perform loss-free beam splitting in the horizontal phase space. Over multiple turns, the resulting beamlets are then transferred to the downstream accelerator. The operational deployment of MTE was rendered possible by the full understanding and mitigation of different hardware limitations and by redesigning the extraction trajectories and non-linear optics, which was required due to the installation of a dummy septum to reduce the activation of the magnetic extraction septum. The results of the related experimental and simulation studies, a summary ...

  9. Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    Energy Technology Data Exchange (ETDEWEB)

    Toivanen, V., E-mail: ville.aleksi.toivanen@cern.ch; Bellodi, G.; Dimov, V.; Küchler, D.; Lombardi, A. M.; Maintrot, M. [European Organization for Nuclear Research (CERN), 1211 Geneva 23 (Switzerland)

    2016-02-15

    Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented.

  10. Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    International Nuclear Information System (INIS)

    Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented

  11. Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN.

    Science.gov (United States)

    Toivanen, V; Bellodi, G; Dimov, V; Küchler, D; Lombardi, A M; Maintrot, M

    2016-02-01

    Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented. PMID:26932084

  12. Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

    Science.gov (United States)

    Toivanen, V.; Bellodi, G.; Dimov, V.; Küchler, D.; Lombardi, A. M.; Maintrot, M.

    2016-02-01

    Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented.

  13. High precision electron beam diagnostic system for high current long pulse beams

    International Nuclear Information System (INIS)

    As part of the effort to develop a multi-axis electron beam transport system using stripline kicker technology for DARHT II applications, it is necessary to precisely determine the position and extent of long high energy beams (6-40 MeV, 1-4 kA, 2 microseconds) for accurate position control. The kicker positioning system utilizes shot-to-shot adjustments for reduction of relatively slow (<20 MHz) motion of the beam centroid. The electron beams passing through the diagnostic systems have the potential for large halo effects that tend to corrupt measurements performed using capacitive pick-off probes. Likewise, transmission line traveling wave probes have problems with multi-bounce effects due to these longer pulse widths. Finally, the high energy densities experienced in these applications distort typical foil beam position measurements

  14. Intense ion beam produced plasmas on TIT-RFQ linac

    International Nuclear Information System (INIS)

    Intense ion beams from an RFQ linac can be used to investigate the plasma experiments. At present, a 4He+ beam with the mean current of 2 mA in a macropulse is focused to about 1.1 mm2 on the target surface. The output-beam is switched from a beam dump to the target within 50 ns by using a fast electrostatic beam kicker. This kicker synchronizes to the RF-pulse, and it is used to control the timing between the beam-target interaction and the diagnostic equipment. The experiments were performed with a gas target. The behavior of the ion beam-produced plasma was observed. (orig.)

  15. High power neutral beam operation at 120 keV with a single stage extraction system

    International Nuclear Information System (INIS)

    A 37 A, 120 keV, 0.1 s pulse length, perveance matched hydrogen beam has been obtained reliably by using a three electrode extraction system with shaped circular apertures illuminated by a rectangular periplasmatron ion source of 12 x 38 cm2 full extraction area. The length of the ''accel'' gap was 2 cm and the extracted ion current density, at 120 keV, J+ = 200 mA/cm2. The injector was operated with a neutralizing gas cell of nl approximately = 7.1015 mol/cm2 gas target thickness. Divergence angles as low as 0.65deg in hydrogen and 0.4deg in argon have been measured. The grid power loadings, normalized to the H.V drain power and to the ion source filling pressure (mTorr) were: 0.1% for the plasma grid, 0.02% for the negative grid and 0.07% for the neutralizer grid. The results show that such a 3-grid system is suitable for high energy injectors required for the JET device and that it can be advantageously utilized instead of a 4-grid system on account of its greater simplicity. (author)

  16. Automated System Calibration and Verification of the Position Measurements for the Los Alamos Isotope Production Facility and the Switchyard Kicker Facilities

    International Nuclear Information System (INIS)

    The Los Alamos Neutron Science Center (LANSCE) facility at Los Alamos National Laboratory has constructed both an Isotope Production Facility (IPF) and a Switchyard Kicker (XDK) as additions to the H+ and H- accelerator. These additions contain eleven Beam Position Monitors (BPMs) that measure the beam's position throughout the transport. The analog electronics within each processing module determines the beam position using the log-ratio technique. For system reliability, calibrations compensate for various temperature drifts and other imperfections in the processing electronics components. Additionally, verifications are periodically implemented by a PC running a National Instruments LabVIEW virtual instrument (VI) to verify continued system and cable integrity. The VI communicates with the processor cards via a PCI/MXI-3 VXI-crate communication module. Previously, accelerator operators performed BPM system calibrations typically once per day while beam was explicitly turned off. One of this new measurement system's unique achievements is its automated calibration and verification capability. Taking advantage of the pulsed nature of the LANSCE-facility beams, the integrated electronics hardware and VI perform calibration and verification operations between beam pulses without interrupting production beam delivery. The design, construction, and performance results of the automated calibration and verification portion of this position measurement system will be the topic of this paper

  17. Beam Transport in Toroidal Magnetic Field

    CERN Document Server

    Joshi, N; Meusel, O; Ratzinger, U

    2016-01-01

    The concept of a storage ring with toroidal magnetic field was presented in the two previous EPAC conferences. Here we report the first results of experiments performed with beam transport in toroidal magnetic fields and details of the injection system. The beam transport experiments were carried out with 30 degree toroidal segments with an axial magnetic field of 0.6T. The multi turn injection system relies on a transverse injection coil together with an electric kicker system.

  18. A FET based kicker for a charge booster for the TRIUMF ISAC project

    International Nuclear Information System (INIS)

    A charge booster unit is required as part of an upgrade to the ISAC facility at TRIUMF. ISAC is an isotope separator coupled to an accelerator. ISAC is presently capable of accelerating only isotopes with atomic mass up to 30. The charge booster will allow ISAC to accelerate all the masses in the periodic table. A fast kicker system has been built to study the characteristics of an existing charge booster, designed by ISN in Grenoble, to assess the suitability of using this charge booster at TRIUMF. This fast kicker will subsequently be used in the TRIUMF ISAC facility for time of flight separation of the chosen charge and to recycle the higher and lower charges back to the charge booster. This will increase the efficiency from 10% to 60%. The kicker system includes a pair of deflector plates. One plate is charged up to -3.5 kV by a PET based modulator, while the other plate is held at ground potential. The modulator consists of two stacks of FETs operating in push pull with variable output voltage, pulse width, and repetition rate from virtually DC to 52 kHz. The measured high voltage output pulse rise and fall times are 63 ns and the minimum pulse width is 350 ns. The maximum pulse width is dependent upon the repetition rate. The large dynamic range for the repetition rate and pulse width required a novel circuit design and control technique, which also resulted in an energy efficient kicker system. This paper describes the design of the kicker system and shows the results of measurements. (author)

  19. Producing multicharged fullerene ion beam extracted from the second stage of tandem-type ECRIS

    Energy Technology Data Exchange (ETDEWEB)

    Nagaya, Tomoki, E-mail: nagaya@nf.eie.eng.osaka-u.ac.jp; Nishiokada, Takuya; Hagino, Shogo; Otsuka, Takuro; Sato, Fuminobu; Kato, Yushi [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871 (Japan); Uchida, Takashi [Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe-shi, Saitama 350-8585 (Japan); Bio-Nano Electronics Research Centre, Toyo University, 2100, Kujirai, Kawagoe-shi, Saitama 350-8585 (Japan); Muramatsu, Masayuki; Kitagawa, Atsushi [National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555 (Japan); Yoshida, Yoshikazu [Graduate School of Interdisciplinary New Science, Toyo University, 2100, Kujirai, Kawagoe-shi, Saitama 350-8585 (Japan); Faculty of Science and Engineering, Toyo University, 2100, Kujirai, Kawagoe-shi, Saitama 350-8585 (Japan)

    2016-02-15

    We have been constructing the tandem-type electron cyclotron resonance ion source (ECRIS). Two ion sources of the tandem-type ECRIS are possible to generate plasma individually, and they also confined individual ion species by each different plasma parameter. Hence, it is considered to be suitable for new materials production. As the first step, we try to produce and extract multicharged C{sub 60} ions by supplying pure C{sub 60} vapor in the second stage plasma because our main target is producing the endohedral fullerenes. We developed a new evaporator to supply fullerene vapor, and we succeeded in observation about multicharged C{sub 60} ion beam in tandem-type ECRIS for the first time.

  20. Shielding for Neutron Beam Extraction Pipes of Chinese Spallation Neutron Source

    International Nuclear Information System (INIS)

    Based on the design of Chinese Spallation Neutron Source (CSNS) target station neutron beam extraction pipes, shielding efficiency was evaluated using the two-dimensional discrete ordinates transport code DORT for different design models. Two-dimensional dose field distribution and the axial distribution were calculated. Meanwhile, an optimal shielding model was obtained from the calculation. The model ensures that the received doses of the hall staff members below the required standard limit. The results show that the shielding model inserted with SS316 steel has a better shielding efficiency than that without SS316 steel. In addition, the model of the shutter front with tungsten plate has a better efficiency than the others. The shielding efficiency of the vary length tungsten plate was discussed. (authors)

  1. Use achromatic beam line for Hall C beam energy measurement

    International Nuclear Information System (INIS)

    There are several different methods to measure accelerator beam energy, for example, from frequency spectrum measurement and calculation of orbit length from accurate measurement of magnetic field in a reference dipole magnet from high precision floating wire analogue, and from detecting the synchrotron radiation emitted from kicker magnets. In this report an achromatic spectrometer method combined with calibrating a reference magnet and determining the deflection angle of spectrometer is proposed. The similar method will be used to measure beam energy in Bates Linear Accelerator Center, a 10-3 accuracy of beam energy measurement is expected

  2. High energy high current neutral beam injector operation with single-stage and two-stage multiaperture extraction systems

    International Nuclear Information System (INIS)

    A three electrode extraction system, for 80 keV operation was developed, which was based on the standard triode concept, but takes advantage of the additional room between apertures necessary for water cooling, to give a pseudo-Pierce shape to the plasma electrode and thus produce beams with good optics. This system has been operated up to 40 A extracted ion beam at 80 keV energy. We have also, after these experiments, operated the injector with a two stage extraction system developed at Culham Laboratory and which was intended for J.E.T. injectors. Some significative results of the study (which cover over two years of experimental work) of these two different extraction systems are presented and discussed

  3. Novel technique for injecting and extracting beams in a circular hadron accelerator without using septum magnets

    Science.gov (United States)

    Franchi, Andrea; Giovannozzi, Massimo

    2015-07-01

    With a few exceptions, all on-axis injection and extraction schemes implemented in circular particle accelerators, synchrotrons, and storage rings, make use of magnetic and electrostatic septa with systems of slow-pulsing dipoles acting on tens of thousands of turns and fast-pulsing dipoles on just a few. The dipoles create a closed orbit deformation around the septa, usually referred to as an orbit bump. A new approach is presented which obviates the need for the septum deflectors. Fast-pulsing elements are still required, but their strength can be minimized by choosing appropriate local accelerator optics. This technique should increase the beam clearance and reduce the usually high radiation levels found around the septa and also reduce the machine impedance introduced by the fast-pulsing dipoles. The basis of the technique is the creation of stable islands around stable fixed points in horizontal phase space. The trajectories of these islands may then be adjusted to match the position and angle of the incoming or outgoing beam.

  4. Radioprotective Properties of Allium sativum (Garlic Extract on Cultured Human Lymphocytes against Electron Beam Radiation

    Directory of Open Access Journals (Sweden)

    Shama N Rao

    2015-03-01

    Full Text Available The radioprotective effects of naturally occurring compounds from herbs have been investigated in vitro and in vivo considering their ethnopharmacological role in prevention and treatment of cancer. Allium sativum supplementation in diet has been shown to be beneficial to cancer patients. The present study was designed to detect the radioprotective effect of garlic extract (GE on cultured human peripheral blood lymphocytes. Garlic bulbs were extracted using ethanol and water separately followed by assays on antioxidant activities to assess the efficiency of radical scavenging capacity of various extracts. Lymphocytes were treated with different concentrations of GE for 2, 4, 6 and 24 hr periods. Cell survival was determined by tryphan blue dye exclusion assay, single strand DNA damage by alkaline comet assay and in vitro cytogenetic damages were evaluated by micronucleus assays. Ethanol boiled GE showed highest radical scavenging capacity and reducing property. Treatment of GE to lymphocytes before and after exposure to 4Gy of electron beam radiation (EBR the percentage of tail DNA was reduced from 24.06±3.92 to 2.87±0.18. The elevated micronucleus formation in radiation control group (13.15±0.75 was significantly reduced in various concentrations of GE treated groups (10.35±0.44, 7.05±1.17, 6.42±0.47 respectively. Cells treated with GE at 10µg/mL showed maximum viability after exposure to EBR. Present investigations indicate that ethanol boiled GE shows good radiation protection at 10µg/mL concentration. However, increase in concentration above this dose though resulted in higher protection, increased cell toxicity was also noticed.

  5. Robust breathing signal extraction from cone beam CT projections based on adaptive and global optimization techniques

    Science.gov (United States)

    Chao, Ming; Wei, Jie; Li, Tianfang; Yuan, Yading; Rosenzweig, Kenneth E.; Lo, Yeh-Chi

    2016-04-01

    We present a study of extracting respiratory signals from cone beam computed tomography (CBCT) projections within the framework of the Amsterdam Shroud (AS) technique. Acquired prior to the radiotherapy treatment, CBCT projections were preprocessed for contrast enhancement by converting the original intensity images to attenuation images with which the AS image was created. An adaptive robust z-normalization filtering was applied to further augment the weak oscillating structures locally. From the enhanced AS image, the respiratory signal was extracted using a two-step optimization approach to effectively reveal the large-scale regularity of the breathing signals. CBCT projection images from five patients acquired with the Varian Onboard Imager on the Clinac iX System Linear Accelerator (Varian Medical Systems, Palo Alto, CA) were employed to assess the proposed technique. Stable breathing signals can be reliably extracted using the proposed algorithm. Reference waveforms obtained using an air bellows belt (Philips Medical Systems, Cleveland, OH) were exported and compared to those with the AS based signals. The average errors for the enrolled patients between the estimated breath per minute (bpm) and the reference waveform bpm can be as low as  -0.07 with the standard deviation 1.58. The new algorithm outperformed the original AS technique for all patients by 8.5% to 30%. The impact of gantry rotation on the breathing signal was assessed with data acquired with a Quasar phantom (Modus Medical Devices Inc., London, Canada) and found to be minimal on the signal frequency. The new technique developed in this work will provide a practical solution to rendering markerless breathing signal using the CBCT projections for thoracic and abdominal patients.

  6. Robust breathing signal extraction from cone beam CT projections based on adaptive and global optimization techniques.

    Science.gov (United States)

    Chao, Ming; Wei, Jie; Li, Tianfang; Yuan, Yading; Rosenzweig, Kenneth E; Lo, Yeh-Chi

    2016-04-21

    We present a study of extracting respiratory signals from cone beam computed tomography (CBCT) projections within the framework of the Amsterdam Shroud (AS) technique. Acquired prior to the radiotherapy treatment, CBCT projections were preprocessed for contrast enhancement by converting the original intensity images to attenuation images with which the AS image was created. An adaptive robust z-normalization filtering was applied to further augment the weak oscillating structures locally. From the enhanced AS image, the respiratory signal was extracted using a two-step optimization approach to effectively reveal the large-scale regularity of the breathing signals. CBCT projection images from five patients acquired with the Varian Onboard Imager on the Clinac iX System Linear Accelerator (Varian Medical Systems, Palo Alto, CA) were employed to assess the proposed technique. Stable breathing signals can be reliably extracted using the proposed algorithm. Reference waveforms obtained using an air bellows belt (Philips Medical Systems, Cleveland, OH) were exported and compared to those with the AS based signals. The average errors for the enrolled patients between the estimated breath per minute (bpm) and the reference waveform bpm can be as low as -0.07 with the standard deviation 1.58. The new algorithm outperformed the original AS technique for all patients by 8.5% to 30%. The impact of gantry rotation on the breathing signal was assessed with data acquired with a Quasar phantom (Modus Medical Devices Inc., London, Canada) and found to be minimal on the signal frequency. The new technique developed in this work will provide a practical solution to rendering markerless breathing signal using the CBCT projections for thoracic and abdominal patients. PMID:27008349

  7. The preparation of particle beams for experiments of hadron physics: Slow extraction at ELFE rate at DESY and ELSA, as well as beam cooling at HERA

    International Nuclear Information System (INIS)

    Various complementary experimental approaches are possible to study hadron physics, all of which require dedicated accelerator facilities. One approach, known as the ELFE rate at DESY project, makes use of a continuous electron beam with an energy of 15 to 25 GeV, a current of at least 30 μA and very small emittance, for fixed target experiments. The formation of such a beam by stretching a pulsed LINAC beam with the help of the HERA electron ring has been studied. At lower beam energies and currents this concept is already being used at the ELSA facility of Bonn University. Here the extraction process has been studied intensively and has been compared with measurements. Another approach to study hadron physics is the use of an electron - ion collider. To achieve high integrated luminosities cooling of the ion beam is necessary, especially in the case of heavy ions. For HERA high energy beam cooling with the help of an electron storage ring has been studied. (orig.)

  8. Extraction and low energy beam transport from a surface ion source at the TRIUMF-ISAC facility

    Science.gov (United States)

    Sen, A.; Ames, F.; Bricault, P.; Lassen, J.; Laxdal, A.; Mjos, A.

    2016-06-01

    A large fraction of radioactive beams produced and delivered at TRIUMF's isotope separator and accelerator facility, ISAC, are using either a surface ion source or a resonant ionization laser ion source, which share a common design. To characterize the operation of the ion sources, simulations were performed to determine the ion beam optics and beam envelope properties of the extracted beam. Furthermore ion-optics calculations were performed to determine the transmission parameters through the mass separator magnet. Emittances are measured in the ISAC low energy beam line right after the mass separator. The recent addition of a channeltron to the Allison emittance meter scanner now allows us to measure emittances for ion beams with intensities as low as 105 ions/s. This is particularly useful for establishing high resolution, high throughput mass separator tunes for radioactive isotope beams. This paper discusses emittance measurements of low intensity beams, typical emittance scans for the surface ion source and the resonant laser ionized source for different source parameters. The observed results are compared to the simulations and discussed.

  9. Extraction of 10 sec/75 keV/70 A ion beams at prototype neutral beam injector unit for JT-60

    International Nuclear Information System (INIS)

    A prototype neutral beam injector for JT-60 was constructed to test and demonstrate a single beam line performance before fabrication of fourteen injector units for JT-60. The system has been operated over 4 months without serious troubles. Ion beams of 10 sec/75 keV/70 A were extracted repeatedly and most of design values were achieved. Accelerator grids were stable during 10 sec pulse, and other components of the system were confirmed to be sufficiently reliable. The system was also operated with a magnetic field which simulated a stray field from JT-60 tokamak. With the stray field applied, no choking effect in a drift tube like PLT or Culham effects were observed at all. (author)

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

    International Nuclear Information System (INIS)

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

  11. Experiments of synchrotron injection using the direct fast chopped H- beam extracted from surface-plasma-type negative hydrogen ion source

    International Nuclear Information System (INIS)

    An experiment of synchrotron injection using the direct fast chopped H- beam extracted from a surface-plasma-type H- ion source has been successfully achieved. The injection phase of the fast chopped beam from linac into the booster synchrotron is adjustable against the center of rf bucket by using this beam. It was obtained that the longitudinal emittance was controlled at the extraction of the booster synchrotron, and that the beam loss during the injection into main ring of the KEK-PS was reduced by this fast chopped beam. (author)

  12. Pulsed power supply for the kicker magnet with SI-thyristors

    International Nuclear Information System (INIS)

    SI (Static Induction)-thyristors are expected as a solid-state high power switch for the kicker magnet in the circular accelerators. Preliminary results of the proto-type power supply of 20 kV - 120 ns, although the intention is 75 kV - 100 ns, for the hadron accelerator and the performance of the SI-thyristor switch of 20 kV - 2 μs pulse width in the KEK-B collider are presented. (author)

  13. A series resonant switching charging circuit for kicker modulator and its simulation study

    International Nuclear Information System (INIS)

    A novel high voltage charging circuit specially designed for the prototype kicker modulator of the Hefei Light Source storage ring was presented. Zero-current series resonant switching techniques and a simple charging voltage control scheme was adopted in the circuit. Simulation model was established to study the performance of the circuit with a high voltage capacitor load. Designed charging voltage stability and repetition rate can be achieved through simulation analysis. Methods to increase the repetition rate are discussed

  14. High energy, high current neutral beam injector operation with single stage and two-stage multi-aperture extraction systems

    International Nuclear Information System (INIS)

    Neutral beam development for JET injectors at FAR laboratory has led to the study of properties of a single stage (triode) and a two-stage (tetrode) multi-aperture extraction system at ion beam powers exceeding the megawatt level and up to 80 keV beam energy. The results of the experimental measurements and of a numerical study of the beam optical qualities and grid power loadings of these systems are presented. Grid power loading levels of less than 1% of the high-voltage drain power were measured in both the triode and the tetrode accelerators. This would allow long pulse operation (10 s with water-cooling) as required for JET. The beam divergence angle (α approx.= 0.70) and the transmission characteristics were almost identical. At the same energy, higher current densities, at optimum perveance, were obtained with the triode at a lower electric field stress on the high-voltage gap. The triode offers the additional advantage of being simpler from the mechanical and electrical points of view. Operation of the injection line with an electrostatic beam dump associated with a grounded source is also demonstrated for a 25 A ion beam up to 60 keV. (orig.)

  15. High energy, high current neutral beam injector operation with single stage and two-stage multi-aperture extraction systems

    Science.gov (United States)

    Becherer, R.; Desmons, M.; Fumelli, M.; Raimbault, P.; Valckx, F. P. G.

    1982-12-01

    Neutral beam development for JET injections at FAR laboratory has led to the study of properties of a single stage (triode) and a two-stage (tetrode) multi-aperture extraction system at ion beam powers exceeding the megawatt level and up to 80 keV beam energy. The results of the experimental measurements and of a numerical study of the beam optical qualities and grid power loadings of these systems are presented. Grid power loading levels of less than 1% of the high-voltage drain power were measured in both the triode and the tetrode accelerators. This would allow long pulse operation (10 s with water-cooling) as required for JET. The beam divergence angle (α ≅ 0.7°) and the transmission characteristics were almostidentical. At the same energy, higher current densities, at optimum perveance, were obtained with the triode at a lower electric field stress on the high-voltage gap. The triode offers the additional advantage of being simpler from the mechanical and electrical points of view. Operation of the injection line with an electrostatic beam dump associated with a grounded source is also demonstrated for a 25 ion beam up to 60 keV.

  16. Preliminary results concerning the simulation of beam profiles from extracted ion current distributions for mini-STRIKE

    Science.gov (United States)

    Agostinetti, P.; Giacomin, M.; Serianni, G.; Veltri, P.; Bonomo, F.; Schiesko, L.

    2016-02-01

    The Radio Frequency (RF) negative hydrogen ion source prototype has been chosen for the ITER neutral beam injectors due to its optimal performances and easier maintenance demonstrated at Max-Planck-Institut für Plasmaphysik, Garching in hydrogen and deuterium. One of the key information to better understand the operating behavior of the RF ion sources is the extracted negative ion current density distribution. This distribution—influenced by several factors like source geometry, particle drifts inside the source, cesium distribution, and layout of cesium ovens—is not straightforward to be evaluated. The main outcome of the present contribution is the development of a minimization method to estimate the extracted current distribution using the footprint of the beam recorded with mini-STRIKE (Short-Time Retractable Instrumented Kalorimeter). To accomplish this, a series of four computational models have been set up, where the output of a model is the input of the following one. These models compute the optics of the ion beam, evaluate the distribution of the heat deposited on the mini-STRIKE diagnostic calorimeter, and finally give an estimate of the temperature distribution on the back of mini-STRIKE. Several iterations with different extracted current profiles are necessary to give an estimate of the profile most compatible with the experimental data. A first test of the application of the method to the BAvarian Test Machine for Negative ions beam is given.

  17. Carbon beam extraction with 14.5 GHz electron cyclotron resonance ion source at Korea Atomic Energy Research Institute.

    Science.gov (United States)

    Lee, Cheol Ho; Oh, Byung-Hoon; Chang, Dae-Sik; Jeong, Sun-Chan

    2014-02-01

    A 14.5 GHz Electron Cyclotron Resonance ion source (ECRIS) has been made to produce C(4+) beam for using a carbon therapy facility and recently tested at KAERI. Highly charged carbon ions have been successfully extracted. When using only CO2 gas, the beam current of C(4+) was almost 14 μA at 15 kV extraction voltage. To get higher current of the C(4+) beam, while optimizing confinement magnetic field configuration (e.g., axial strengths at minimum and extraction side), gas-mixing (CO2/He), and biased disk were introduced. When the gas mixing ratio of the CO2/He gas is 1:8 at an operational pressure of 5 × 10(-7) mbar and the disk was biased to -150 V relative to the ion source body, the highest current of the C(4+) beam was achieved to be 50 μA, more than three times higher than previously observed only with CO2 gas. Some details on the operating conditions of the ECRIS were discussed. PMID:24593482

  18. Preliminary results concerning the simulation of beam profiles from extracted ion current distributions for mini-STRIKE

    Energy Technology Data Exchange (ETDEWEB)

    Agostinetti, P., E-mail: piero.agostinetti@igi.cnr.it; Serianni, G.; Veltri, P. [Consorzio RFX (CNR, ENEA, INFN, Università di Padova, Acciaierie Venete SpA), Corso Stati Uniti 4, 35127 Padova (Italy); Giacomin, M. [Physics Department, Università di Padova, via F. Marzolo 8, 35131 Padova (Italy); Bonomo, F.; Schiesko, L. [Max-Planck-Institut für Plasmaphysik, Boltzmannstrasse 2, D-85748 Garching (Germany)

    2016-02-15

    The Radio Frequency (RF) negative hydrogen ion source prototype has been chosen for the ITER neutral beam injectors due to its optimal performances and easier maintenance demonstrated at Max-Planck-Institut für Plasmaphysik, Garching in hydrogen and deuterium. One of the key information to better understand the operating behavior of the RF ion sources is the extracted negative ion current density distribution. This distribution—influenced by several factors like source geometry, particle drifts inside the source, cesium distribution, and layout of cesium ovens—is not straightforward to be evaluated. The main outcome of the present contribution is the development of a minimization method to estimate the extracted current distribution using the footprint of the beam recorded with mini-STRIKE (Short-Time Retractable Instrumented Kalorimeter). To accomplish this, a series of four computational models have been set up, where the output of a model is the input of the following one. These models compute the optics of the ion beam, evaluate the distribution of the heat deposited on the mini-STRIKE diagnostic calorimeter, and finally give an estimate of the temperature distribution on the back of mini-STRIKE. Several iterations with different extracted current profiles are necessary to give an estimate of the profile most compatible with the experimental data. A first test of the application of the method to the BAvarian Test Machine for Negative ions beam is given.

  19. Development of the magnetic septa for the slow beam extraction from the J-PARC main ring

    International Nuclear Information System (INIS)

    The magnetic septa have been developed for the slow extraction from the J-PARC Main Ring (MR) to the Hadron Experimental Facility. They consist of two thin magnetic septa (SMS1), four medium thick septa (SMS2) and four thick septa (SMS3). The thinnest septum conductor is 1.5 mm thick. The typical operating current is DC 3000 A and the total kick angle with the 30 GeV proton beam is 77 mrad. The magnets of SMS1 and SMS2 are placed in the vacuum chambers with the diameter of 660 mm, and the chambers can be aligned remotely by stepping motors in the range of ±5mm, which enable us to minimize the beam loss by the magnetic septa. The septa were installed in the MR in December 2008, and were successfully operated in the beam time for the slow beam extraction in January and February 2009, which resulted in the first 30GeV beam delivery to the Hadron Experimental Facility. (author)

  20. Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (Te) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (ne) is in the range 108--1010-cm at the skimmer tip and drops abruptly to 106--108 cm-3 near the skimmer tip and drops abruptly to 106--108 cm-3 downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 104--105 downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z2 intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z2 fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument

  1. Beam size reduction of a several hundred-keV compact ion microbeam system by improving the extraction condition in an ion source

    International Nuclear Information System (INIS)

    A several hundred-keV compact ion microbeam system with a three-stage acceleration lens has been developed to form an ion beam of several micrometers in diameter. In a previous study of the Ohkubo et al. (2013) and Ishii et al. (2014), a hydrogen beam of 143 keV having 17 μm diameter was experimentally formed using such a microbeam system. It was demonstrated that a three-stage acceleration lens functioned as a focusing lens and indicated that the beam diameter (hereinafter referred to as the “beam size”) depended on the extraction voltage to generate the ion beam and the vacuum pressure in the extraction space in a plasma-type ion source. In this study, the hydrogen beam sizes were experimentally measured at 130 keV as functions of the extraction voltage and vacuum pressure to form the beam size with several micrometers in diameter. These two relationships showed that beam sizes were reduced in the extraction voltage range of 400–500 V and when the vacuum pressure was lowered to a minimum value of 5.33 × 10−5 Pa. In addition, the result showed that the beam size was dominantly influenced by the vacuum pressure. Consequently, a hydrogen beam 5.8 μm in diameter was formed experimentally—the smallest beam yet obtained

  2. Modeling of the negative ions extraction from a hydrogen plasma source. Application to ITER Neutral Beam Injector

    International Nuclear Information System (INIS)

    The development of a high performance negative ion (NI) source constitutes a crucial step in the construction of a Neutral Beam Injector of the future fusion reactor ITER. NI source should deliver 40 A of H- or of D-. To address this problem in a realistic way, a 3D particles-in-cell electrostatic collisional code was developed. Binary collisions between the particles are introduced using Monte-Carlo collision scheme. This code called ONIX was used to investigate the plasma properties and the transport of the charged particles close to a typical extraction aperture. Results obtained from this code are presented in this thesis. They include negative ions and electrons 3D trajectories. The ion and electron current density profiles are shown for different local magnetic field configurations. Results of production, destruction, and transport of H- in the extraction region are also presented. The production of H- is investigated via 3 atomic processes: 1) electron dissociative attachment to the vibrationally excited molecules H2(v) in the volume, 2) interaction of the positive ions H+ and H2+ with the aperture wall and 3) collisions of the neutral gas H, H2 with aperture wall. The influence of each process on the total extracted NI current is discussed. The extraction efficiency of H- from the volume is compared to the one of H- coming from the wall. Moreover, a parametric study of the H- surface production is presented. Results show the role of sheath behavior in the vicinity of the aperture developing a double layer structure responsible of the NI extraction limitations. The 2 following issues are also analysed. First the influence of the external extracted potential value on the formation of negative sheath and secondly the strength of the magnetic filter on the total extracted NI and co-extracted electron current. The suppression of the electron beam by the negative ion produced at the plasma grid wall is also discussed. Results are in good agreement with available

  3. Synergistic Effects of Electron-beam Irradiation and Leek Extract on the Quality of Pork Jerky during Ambient Storage

    OpenAIRE

    Kim, Hyun-Joo; Kang, Mingu; Yong, Hae In; Bae, Young Sik; Jung, Samooel; Jo, Cheorun

    2013-01-01

    To investigate the synergistic effect(s) of electron-beam (EB) irradiation and leek (Allium tuberosum Rottler) extract on the quality of pork jerky during ambient storage, we irradiated prepared pork jerky samples (control and samples with 0.5% and 1.0% leek extract) with EB technology at doses of 0, 1, 2, and 4 kGy, stored them for 2 months at 25°C, and analyzed them. Water activity was 0.73 to 0.77 in non-irradiated samples, and no significant difference in the water activity was observed b...

  4. Electron stripping processes of H- ion beam in the 80 kV high voltage extraction column and low energy beam transport line at LANSCE

    Science.gov (United States)

    Draganic, I. N.

    2016-02-01

    Basic vacuum calculations were performed for various operating conditions of the Los Alamos National Neutron Science H- Cockcroft-Walton (CW) injector and the Ion Source Test Stand (ISTS). The vacuum pressure was estimated for both the CW and ISTS at five different points: (1) inside the H- ion source, (2) in front of the Pierce electrode, (3) at the extraction electrode, (4) at the column electrode, and (5) at the ground electrode. A static vacuum analysis of residual gases and the working hydrogen gas was completed for the normal ion source working regime. Gas density and partial pressure were estimated for the injected hydrogen gas. The attenuation of H- beam current and generation of electron current in the high voltage acceleration columns and low energy beam transport lines were calculated. The interaction of H- ions on molecular hydrogen (H2) is discussed as a dominant collision process in describing electron stripping rates. These results are used to estimate the observed increase in the ratio of electrons to H- ion beam in the ISTS beam transport line.

  5. Electron stripping processes of H− ion beam in the 80 kV high voltage extraction column and low energy beam transport line at LANSCE

    International Nuclear Information System (INIS)

    Basic vacuum calculations were performed for various operating conditions of the Los Alamos National Neutron Science H− Cockcroft-Walton (CW) injector and the Ion Source Test Stand (ISTS). The vacuum pressure was estimated for both the CW and ISTS at five different points: (1) inside the H− ion source, (2) in front of the Pierce electrode, (3) at the extraction electrode, (4) at the column electrode, and (5) at the ground electrode. A static vacuum analysis of residual gases and the working hydrogen gas was completed for the normal ion source working regime. Gas density and partial pressure were estimated for the injected hydrogen gas. The attenuation of H− beam current and generation of electron current in the high voltage acceleration columns and low energy beam transport lines were calculated. The interaction of H− ions on molecular hydrogen (H2) is discussed as a dominant collision process in describing electron stripping rates. These results are used to estimate the observed increase in the ratio of electrons to H− ion beam in the ISTS beam transport line

  6. Comparison of gamma ray and electron beam irradiation on extraction yield, morphological and antioxidant properties of polysaccharides from tamarind seed

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jong-il [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Kim, Jae-Kyung [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Srinivasan, Periasamy; Kim, Jae-Hun [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Park, Hyun-Jin [Graduate school of Food and Biotechnology, Korea University, Seoul 146-701 (Korea, Republic of); Byun, Myung-Woo [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of); Lee, Ju-Woon [Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup 580-185 (Korea, Republic of)], E-mail: sjwlee@kaeri.re.kr

    2009-07-15

    Tamarind (Tamarindus indica L) seed polysaccharide (TSP) is of great important due to its various biological activities. The present investigation was carried out to compare extraction yield, morphological characteristics, average molecular weights and antioxidant activities of TSP from gamma- and electron beam (EB)-irradiated tamarind kernel powder. The tamarind kernel powder was irradiated with 0, 5 and 10 kGy by gamma ray (GR) and electron beam, respectively. The extraction yield of TSP was increased significantly by EB and GR irradiation, but there was no significant difference between irradiation types. Morphological studies by scanning electron microscope showed that TSP from GR-irradiated tamarind seed had a fibrous structure, different from that of EB irradiated with a particle structures. The average molecular weight of TSP was decreased by the irradiation, and EB treatment degraded more severely than GR. Superoxide radical scavenging ability and total antioxidant capacity of EB-treated TSP showed higher than those of GR-treated TSP.

  7. On the meniscus formation and the negative hydrogen ion extraction from ITER neutral beam injection relevant ion source

    Science.gov (United States)

    Mochalskyy, S.; Wünderlich, D.; Ruf, B.; Fantz, U.; Franzen, P.; Minea, T.

    2014-10-01

    The development of a large area (Asource,ITER = 0.9 × 2 m2) hydrogen negative ion (NI) source constitutes a crucial step in construction of the neutral beam injectors of the international fusion reactor ITER. To understand the plasma behaviour in the boundary layer close to the extraction system the 3D PIC MCC code ONIX is exploited. Direct cross checked analysis of the simulation and experimental results from the ITER-relevant BATMAN source testbed with a smaller area (Asource,BATMAN ≈ 0.32 × 0.59 m2) has been conducted for a low perveance beam, but for a full set of plasma parameters available. ONIX has been partially benchmarked by comparison to the results obtained using the commercial particle tracing code for positive ion extraction KOBRA3D. Very good agreement has been found in terms of meniscus position and its shape for simulations of different plasma densities. The influence of the initial plasma composition on the final meniscus structure was then investigated for NIs. As expected from the Child-Langmuir law, the results show that not only does the extraction potential play a crucial role on the meniscus formation, but also the initial plasma density and its electronegativity. For the given parameters, the calculated meniscus locates a few mm downstream of the plasma grid aperture provoking a direct NI extraction. Most of the surface produced NIs do not reach the plasma bulk, but move directly towards the extraction grid guided by the extraction field. Even for artificially increased electronegativity of the bulk plasma the extracted NI current from this region is low. This observation indicates a high relevance of the direct NI extraction. These calculations show that the extracted NI current from the bulk region is low even if a complete ion-ion plasma is assumed, meaning that direct extraction from surface produced ions should be present in order to obtain sufficiently high extracted NI current density. The calculated extracted currents, both ions

  8. Learning of Soccer Player Agents Using a Policy Gradient Method : Coordination Between Kicker and Receiver During Free Kicks

    Directory of Open Access Journals (Sweden)

    Harukazu Igarashi, Koji Nakamura & Seiji Ishihara

    2011-04-01

    Full Text Available As an example of multi-agent learning in soccer games of the RoboCup 2D Soccer SimulationLeague, we dealt with a learning problem between a kicker and a receiver when a direct free kickis awarded just outside the opponent’s penalty area. We propose how to use a heuristic functionto evaluate an advantageous target point for safely sending/receiving a pass and scoring. Theheuristics include an interaction term between a kicker and a receiver to intensify theircoordination. To calculate the interaction term, we let a kicker/receiver agent have areceiver’s/kicker’s action decision model to predict a receiver’s/kicker’s action. Parameters in theheuristic function can be learned by a kind of reinforcement learning called the policy gradientmethod. Our experiments show that if the two agents do not have the same type of heuristics, theinteraction term based on prediction of a teammate’s decision model leads to learning a masterservantrelation between a kicker and a receiver, where a receiver is a master and a kicker is aservant.

  9. Improvements on the accuracy of beam bugs

    International Nuclear Information System (INIS)

    At LLNL resistive wall monitors are used to measure the current and position used on ETA-II show a droop in signal due to a fast redistribution time constant of the signals. This paper presents the analysis and experimental test of the beam bugs used for beam current and position measurements in and after the fast kicker. It concludes with an outline of present and future changes that can be made to improve the accuracy of these beam bugs. of intense electron beams in electron induction linacs and beam transport lines. These, known locally as ''beam bugs'', have been used throughout linear induction accelerators as essential diagnostics of beam current and location. Recently, the development of a fast beam kicker has required improvement in the accuracy of measuring the position of beams. By picking off signals at more than the usual four positions around the monitor, beam position measurement error can be greatly reduced. A second significant source of error is the mechanical variation of the resistor around the bug

  10. Improvements on the accuracy of beam bugs

    International Nuclear Information System (INIS)

    At LLNL resistive wall monitors are used to measure the current and position used on ETA-II show a droop in signal due to a fast redistribution time constant of the signals. This paper presents the analysis and experimental test of the beam bugs used for beam current and position measurements in and after the fast kicker. It concludes with an outline of present and future changes that can be made to improve the accuracy of these beam bugs. of intense electron beams in electron induction linacs and beam transport lines. These, known locally as beam bugs, have been used throughout linear induction accelerators as essential diagnostics of beam current and location. Recently, the development of a fast beam kicker has required improvement in the accuracy of measuring the position of beams. By picking off signals at more than the usual four positions around the monitor, beam position measurement error can be greatly reduced. A second significant source of error is the mechanical variation of the resistor around the bug

  11. Upgrade of the beam transport lines and the beam-abort system and development of a tune compensator in KEKB

    Science.gov (United States)

    Iida, Naoko; Kikuchi, Mitsuo; Mimashi, Toshihiro; Nakayama, Hisayoshi; Sakamoto, Yutaka; Satoh, Kotaro; Takasaki, Seiji; Tawada, Masafumi

    2013-03-01

    The KEKB collider achieved a maximum peak luminosity of 2.1×1034 cm-2 s-1 and an integrated luminosity of 1 ab-1 in its ten-year operation. Behind these glorious records there have been uncountable improvements in every subsystem. This paper describes the improvements in the beam transport line, injection kickers, septum magnets, the beam-abort system, and a newly developed pulsed-quadrupole system in detail.

  12. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics

    Science.gov (United States)

    Yorita, T.; Hatanaka, K.; Fukuda, M.; Ueda, H.; Yasuda, Y.; Morinobu, S.; Tamii, A.; Kamakura, K.

    2014-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP.

  13. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics

    International Nuclear Information System (INIS)

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP

  14. Studies of extraction and transport system for highly charged ion beam of 18 GHz superconducting electron cyclotron resonance ion source at Research Center for Nuclear Physics.

    Science.gov (United States)

    Yorita, T; Hatanaka, K; Fukuda, M; Ueda, H; Yasuda, Y; Morinobu, S; Tamii, A; Kamakura, K

    2014-02-01

    An 18 GHz superconducting electron cyclotron resonance ion source is installed to increase beam currents and to extend the variety of ions especially for highly charged heavy ions which can be accelerated by cyclotrons of Research Center for Nuclear Physics (RCNP), Osaka University. The beam production developments of several ions from B to Xe have been already done [T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 79, 02A311 (2008) and T. Yorita, K. Hatanaka, M. Fukuda, M. Kibayashi, S. Morinobu, H.Okamura, and A. Tamii, Rev. Sci. Instrum. 81, 02A332 (2010)] and the further studies for those beam extraction and its transport have been done in order to increase the beam current more. The plasma electrode, extraction electrode, and einzel lens are modified. Especially extraction electrode can be applied minus voltage for the beam extraction and it works well to improve the extracted beam current. The extraction voltage dependences of transmission and emittance also have been studied for beam current improvement which is injected into azimuthally varying field cyclotron at RCNP. PMID:24593475

  15. Evaluation of Beam Loss and Energy Depositions for a Possible Phase II Design for LHC Collimation

    Energy Technology Data Exchange (ETDEWEB)

    Lari, L.; /EPFL-ISIC, Lausanne /CERN; Assmann, R.; /CERN; Bracco, C.; /EPFL-ISIC, Lausanne /CERN; Brugger, M.; /CERN; Cerutti, F.; /CERN; Doyle, E.; /SLAC; Ferrari, A.; /CERN; Keller, L.; Lundgren, S.; Markiewicz, Thomas W.; /SLAC; Mauri, M.; Redaelli, S.; Sarchiapone, L.; /CERN; Smith, J.; /SLAC; Vlachoudis, V.; Weiler, T.; /CERN

    2011-11-07

    The LHC beams are designed to have high stability and to be stored for many hours. The nominal beam intensity lifetime is expected to be of the order of 20h. The Phase II collimation system has to be able to handle particle losses in stable physics conditions at 7 TeV in order to avoid beam aborts and to allow correction of parameters and restoration to nominal conditions. Monte Carlo simulations are needed in order to evaluate the behavior of metallic high-Z collimators during operation scenarios using a realistic distribution of losses, which is a mix of the three limiting halo cases. Moreover, the consequences in the IR7 insertion of the worst (case) abnormal beam loss are evaluated. The case refers to a spontaneous trigger of the horizontal extraction kicker at top energy, when Phase II collimators are used. These studies are an important input for engineering design of the collimation Phase II system and for the evaluation of their effect on adjacent components. The goal is to build collimators that can survive the expected conditions during LHC stable physics runs, in order to avoid quenches of the SC magnets and to protect other LHC equipments.

  16. Evaluation of Beam Losses And Energy Deposition for a Possible Phase II Design for LHC Collimation

    Energy Technology Data Exchange (ETDEWEB)

    Lari, L.; Assmann, R.W.; Bracco, C.; Brugger, M.; Cerutti, F.; Ferrari, A.; Mauri, M.; Redaelli, S.; Sarchiapone, L.; Vlachoudis, Vasilis; Weiler, Th.; /CERN; Doyle, J.E.; Keller, L.; Lundgren, S.A.; Markiewicz, Thomas W.; Smith, J.C.; /SLAC; Lari, L.; /LPHE, Lausanne

    2011-11-01

    The Large Hadron Collider (LHC) beams are designed to have high stability and to be stored for many hours. The nominal beam intensity lifetime is expected to be of the order of 20h. The Phase II collimation system has to be able to handle particle losses in stable physics conditions at 7 TeV in order to avoid beam aborts and to allow correction of parameters and restoration to nominal conditions. Monte Carlo simulations are needed in order to evaluate the behavior of metallic high-Z collimators during operation scenarios using a realistic distribution of losses, which is a mix of the three limiting halo cases. Moreover, the consequences in the IR7 insertion of the worst (case) abnormal beam loss are evaluated. The case refers to a spontaneous trigger of the horizontal extraction kicker at top energy, when Phase II collimators are used. These studies are an important input for engineering design of the collimation Phase II system and for the evaluation of their effect on adjacent components. The goal is to build collimators that can survive the expected conditions during LHC stable physics runs, in order to avoid quenches of the SC magnets and to protect other LHC equipments.

  17. Production of cold beams of ND3 with variable rotational state distributions by electrostatic extraction of He and Ne buffer-gas-cooled beams

    International Nuclear Information System (INIS)

    The measurement of the rotational state distribution of a velocity-selected, buffer-gas-cooled beam of ND3 is described. In an apparatus recently constructed to study cold ion-molecule collisions, the ND3 beam is extracted from a cryogenically cooled buffer-gas cell using a 2.15 m long electrostatic quadrupole guide with three 90° bends. (2+1) resonance enhanced multiphoton ionization spectra of molecules exiting the guide show that beams of ND3 can be produced with rotational state populations corresponding to approximately Trot = 9–18 K, achieved through manipulation of the temperature of the buffer-gas cell (operated at 6 K or 17 K), the identity of the buffer gas (He or Ne), or the relative densities of the buffer gas and ND3. The translational temperature of the guided ND3 is found to be similar in a 6 K helium and 17 K neon buffer-gas cell (peak kinetic energies of 6.92(0.13) K and 5.90(0.01) K, respectively). The characterization of this cold-molecule source provides an opportunity for the first experimental investigations into the rotational dependence of reaction cross sections in low temperature collisions

  18. Characterization of an ion beam produced by extraction and acceleration of ions from a wire plasma source

    International Nuclear Information System (INIS)

    In this study we first model a DC low pressure wire plasma source and then characterize the properties of an ion gun derived from the plasma source. In order to study the properties of the derived ion gun, we develop a particle-in-cell code fitted to the modelling of the wire plasma source operation, and validate it by confrontation with the results of an experimental study. In light of the simulation results, an analysis of the wire discharge in terms of a collisional Child-Langmuir ion flow in cylindrical geometry is proposed. We interpret the mode transition as a natural reorganization of the discharge when the current is increased above a threshold value which is a function of the discharge voltage, the pressure and the inter-electrodes distance. In addition, the analysis of the energy distribution function of ions impacting the cathode demonstrates the ability to extract an ion beam of low energy spread around the discharge voltage assuming that the discharge is operated in its high pressure mode. An ion source prototype allowing the extraction and acceleration of ions from the wire source is then proposed. The experimental study of such a device confirms that, apart from a shift corresponding to the accelerating voltage, the acceleration scheme does not spread the ion velocity distribution function along the axis of the beam. It is therefore possible to produce tunable energy (0 - 5 keV) ion beams of various ionic species presenting limited energy dispersion ( 10 eV). The typical beam currents are about a few tens of micro-amperes, and the divergence of such a beam is on the order of one degree. A numerical modelling of the ion source is eventually conducted in order to identify potential optimizations of the concept. (author)

  19. Learning of Soccer Player Agents Using a Policy Gradient Method : Coordination Between Kicker and Receiver During Free Kicks

    OpenAIRE

    Harukazu Igarashi, Koji Nakamura & Seiji Ishihara

    2011-01-01

    As an example of multi-agent learning in soccer games of the RoboCup 2D Soccer SimulationLeague, we dealt with a learning problem between a kicker and a receiver when a direct free kickis awarded just outside the opponent’s penalty area. We propose how to use a heuristic functionto evaluate an advantageous target point for safely sending/receiving a pass and scoring. Theheuristics include an interaction term between a kicker and a receiver to intensify theircoordination. To calculate the inte...

  20. Learning of Soccer Player Agents Using a Policy Gradient Method : Coordination Between Kicker and Receiver During Free Kicks

    OpenAIRE

    Harukazu Igarashi; Koji Nakamura; Seiji Ishihara

    2011-01-01

    As an example of multi-agent learning in soccer games of the RoboCup 2D Soccer Simulation League, we dealt with a learning problem between a kicker and a receiver when a direct free kick is awarded just outside the opponent's penalty area. We propose how to use a heuristic function to evaluate an advantageous target point for safely sending/receiving a pass and scoring. The heuristics include an interaction term between a kicker and a receiver to intensify their coordination. To calculate the...

  1. Fundamental studies of the plasma extraction and ion beam formation processes in inductively coupled plasma mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Niu, Hongsen

    1995-02-10

    The fundamental and practical aspects are described for extracting ions from atmospheric pressure plasma sources into an analytical mass spectrometer. Methodologies and basic concepts of inductively coupled plasma mass spectrometry (ICP-MS) are emphasized in the discussion, including ion source, sampling interface, supersonic expansion, slumming process, ion optics and beam focusing, and vacuum considerations. Some new developments and innovative designs are introduced. The plasma extraction process in ICP-MS was investigated by Langmuir measurements in the region between the skimmer and first ion lens. Electron temperature (T{sub e}) is in the range 2000--11000 K and changes with probe position inside an aerosol gas flow. Electron density (n{sub e}) is in the range 10{sup 8}--10{sup 10} {sup {minus}cm }at the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} near the skimmer tip and drops abruptly to 10{sup 6}--10{sup 8} cm{sup {minus}3} downstream further behind the skimmer. Electron density in the beam leaving the skimmer also depends on water loading and on the presence and mass of matrix elements. Axially resolved distributions of electron number-density and electron temperature were obtained to characterize the ion beam at a variety of plasma operating conditions. The electron density dropped by a factor of 101 along the centerline between the sampler and skimmer cones in the first stage and continued to drop by factors of 10{sup 4}--10{sup 5} downstream of skimmer to the entrance of ion lens. The electron density in the beam expansion behind sampler cone exhibited a 1/z{sup 2} intensity fall-off (z is the axial position). An second beam expansion originated from the skimmer entrance, and the beam flow underwent with another 1/z{sup 2} fall-off behind the skimmer. Skimmer interactions play an important role in plasma extraction in the ICP-MS instrument.

  2. Synergistic Effects of Electron-beam Irradiation and Leek Extract on the Quality of Pork Jerky during Ambient Storage.

    Science.gov (United States)

    Kim, Hyun-Joo; Kang, Mingu; Yong, Hae In; Bae, Young Sik; Jung, Samooel; Jo, Cheorun

    2013-04-01

    To investigate the synergistic effect(s) of electron-beam (EB) irradiation and leek (Allium tuberosum Rottler) extract on the quality of pork jerky during ambient storage, we irradiated prepared pork jerky samples (control and samples with 0.5% and 1.0% leek extract) with EB technology at doses of 0, 1, 2, and 4 kGy, stored them for 2 months at 25°C, and analyzed them. Water activity was 0.73 to 0.77 in non-irradiated samples, and no significant difference in the water activity was observed between the samples treated with leek and the control. The total aerobic bacterial count was significantly decreased with an increase in the irradiation dose and leek extract addition when compared to that of the control (4.54±0.05 log CFU/g). Further, the Hunter color values (L*, a*, and b*) were found to be significantly decreased following leek extract addition and EB irradiation. However, the color values, especially the a* value of the irradiated samples significantly increased during storage. Notably, increasing the EB irradiation dose enhanced the peroxide value. Sensory evaluation revealed that irradiation decreased flavor and overall acceptability. Our findings suggest the use of EB irradiation in combination with leek extract to improve the microbiological safety of pork jerky. However, in order to meet market requirements, novel methods to enhance the sensory quality of pork jerky are warranted. PMID:25049828

  3. Radioprotective effect of Tamarindus indica pod extract in Swiss albino mice exposed to whole body electron beam radiation

    International Nuclear Information System (INIS)

    The objective of the study was to investigate the radioprotective effect of Tamarindus indica pod extract against radiation induced damage.The effect of 100 mg of hydroalcoholic extract of Tamarindus indica pod was studied in Swiss albino mice exposed to 6 Gy whole body electron beam radiation. Treatment of mice with extract for 15 days before irradiation reduced the symptoms of radiation sickness when compared with the untreated irradiated group. The irradiated animals showed an elevation in lipid peroxidation and reduction in glutathione, total antioxidants and antioxidant enzymes such as glutathione peroxidase and catalase activities. Radiation induced mice has shown micronucleus in the bone marrow cells. Treatment of mice with Tamarindus indica pod extract before irradiation caused a significant reduction in lipid peroxidation followed by significant elevation in reduced glutathione, total antioxidants, glutathione peroxidase and catalase activity. It also showed a reduction in the micronucleus formation in bone marrow cells. Results indicate that the radioprotective activity of Tamarindus indica pod extract may be due to free radical scavenging attributed as a result of increased antioxidant level in mice. (author)

  4. Determination of intensity and position of the extracted electron beam at ELSA by means of high-frequency resonators

    International Nuclear Information System (INIS)

    The electron stretcher facility ELSA provides an electron beam of a few hundred pA used for the generation of bremsstrahlung photons probing the nucleon structure in a detector setup. For the correct interpretation of the events registered, the persistence of the beam position over time is crucial. Its continuous monitoring has been enabled by setting up a measurement system based on resonant cavities. Position signals at a frequency of 1.5 GHz and below one aW of power can be abstracted from the beam without degrading its quality. After frequency down-conversion to a few kHz, a narrow bandwidth detection performed by lock-in amplifiers separates them from noise. A maximum sample rate of 9 Hz and a resolution of one tenth of a millimeter could be achieved. The position signals have to be normalized to the beam current which is monitored by another dedicated resonator. The measurement precision down to a few pA allows for the accelerator extraction mechanism to be controlled by a feedback loop in order to obtain the respective requested current. (orig.)

  5. Development of a PIXE (Particle Induced X-ray Emission) analysis device using an extracted proton beam

    International Nuclear Information System (INIS)

    The experimental device described allows the extention of the PIXE (Particle Induced X-ray Emission) method to the analysis, by means of proton beams, of solid or liquid samples, which can not be analyzed under vacuum conditions. The homogeneity of the surfaces to be analysed and elements (in the atmosphere) which absorb X-rays must be taken into account. Liquid samples do not need special care. The results show that: at high energies, the extracted beam sensibility is of the same order of magnitude as those obtained under vacuum; at low energies, the performance under vacuum conditions is better. The particles energy losses, at the exit membrane and in the outer atmosphere, decrease the X-rays production efficiency

  6. Electronic regulation of the SPS extraction quadrupole current pulse shape for improved stability of the extracted beam

    CERN Document Server

    Carlier, E; Vossenberg, Eugène B; CERN. Geneva. SPS and LEP Division

    1996-01-01

    In order to minimise the event pile-up and therefore optimise the detection efficiency, Chorus and Nomad experiments ask for a long and rectangular spill profile. At present the fast-slow extractio n is generated by driving the beam into a quadrupolar-octopolar resonance by exciting a quadrupole magnet with a semi-trapezoidal current [1]. The trapezoidal pulse shape is obtained by dischargin g a capacitor into the magnet coils. After a few milliseconds of undamped discharge a fixed resistor is switched into the circuit. The attenuation is then higher and the sine wave continues with a lower gradient. The two gradients can be adjusted by varying the initial capacitor voltage and the time at which the resistor is switched into the circuit. A further degree of freedom in determini ng the spill shape has been added by allowing the possibility of changing the second slope value independently of the initial conditions. This task is achieved by means of a variable current sour ce added in parallel to the fixed resis...

  7. Study of a single-charged ions ECR source matching of the extracted beam to an isotope separator

    International Nuclear Information System (INIS)

    A new ECR ion-source has been designed and studied for single-charged ion beams. A very stable regime has been obtained with an ion-source made of two identical stages in cascade. The RF power supplies consist of two 2.45 GHZ magnetrons. The discharge chamber is made of two coaxial Pyrex tubes. The external one ensures vacuum and HT insulation. The tubes are aligned inside the two multi-mode cavities axially limited by three magnetic coils. The ion beam is extracted at 20 kV and focused with electric lenses. For argon and xenon, 1 mA single-charged ion currents have been extracted. The influence of various parameters has been progressively achieved with a set-up including a 600 analyzing magnet and with the 1200 on-line isotope separator at SARA. From emittances and images observed it appears difficult to compensate charge space effects. Suggestions and future developments are proposed to improve qualities of the isotopic separation

  8. Source fabrication and lifetime for Li+ ion beams extracted from alumino-silicate sources

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W

    2012-03-05

    A space-charge-limited beam with current densities (J) exceeding 1 mA/cm2 have been measured from lithium alumino-silicate ion sources at a temperature of ~1275 °C. At higher extraction voltages, the source appears to become emission limited with J ≥ 1.5 mA/cm2, and J increases weakly with the applied voltage. A 6.35 mm diameter source with an alumino-silicate coating, ≤0.25 mm thick, has a measured lifetime of ~40 h at ~1275 °C, when pulsed at 0.05 Hz and with pulse length of ~6 μs each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. Finally, the source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be further extended if the temperature is reduced between pulses.

  9. Source fabrication and lifetime for Li+ ion beams extracted from alumino-silicate sources

    Energy Technology Data Exchange (ETDEWEB)

    Roy, Prabir K.; Greenway, Wayne G.; Kwan, Joe W.

    2012-04-01

    A space-charge-limited beam with current densities (J) exceeding 1 mA/cm2 have been measured from lithium alumino-silicate ion sources at a temperature of ~1275 °C. At higher extraction voltages, the source appears to become emission limited with J ≥ 1.5 mA/cm2, and J increases weakly with the applied voltage. A 6.35 mm diameter source with an alumino-silicate coating, ≤0.25 mm thick, has a measured lifetime of ~40 h at ~1275 °C, when pulsed at 0.05 Hz and with pulse length of ~6 μs each. At this rate, the source lifetime was independent of the actual beam charge extracted due to the loss of neutral atoms at high temperature. Finally, the source lifetime increases with the amount of alumino-silicate coated on the emitting surface, and may also be further extended if the temperature is reduced between pulses.

  10. Calculation of ion beam species extracted from a hydrogen ion source

    International Nuclear Information System (INIS)

    Ion species from a hydrogen ion source are calculated as a function of the electron density on the assumption that the energy distribution of electrons in the source is Maxwellian with temperatures 8 to 12 eV. The beam fraction of ion species depends only on the electron density, and the proton ratio increases with electron density. (author)

  11. Broadband feedback systems for the damping of coherent beam instabilities in the stretcher ring ELSA; Breitbandige Feedback-Systeme zur Daempfung kohaerenter Strahlinstabilitaeten am Stretcherring ELSA

    Energy Technology Data Exchange (ETDEWEB)

    Roth, Andre

    2012-12-15

    At the Electron Stretcher Facility ELSA an upgrade of the internal beam current up to 200 mA would be desirable in order to increase the intensity of the extracted electron beam for the future experimental hadron physics program. However, such an upgrade is mainly limited by the excitation of coherent beam instabilities in the stretcher ring. As active counteraction, broadband bunch-by-bunch feedback-systems for the longitudinal, as well as for both transverse planes were installed. After detection of the motion of each of the 27 4 stored bunches via beam position monitors, the systems determine independent correction signals for each bunch using digital signal processors. The amplified correction signals are applied to the beam by means of broadband longitudinal and transverse kicker structures. The detailed setup, the commissioning procedure and measurement results of the damping performance of the systems are presented. In addition, the operation of the longitudinal system during the fast energy ramp of 4 GeV/s from 1.2 GeV to 3.2 GeV is investigated.

  12. Surface contamination and electrical damage by focused ion beam: conditions applicable to the extraction of TEM lamellae from nanoelectronic devices

    International Nuclear Information System (INIS)

    Focused ion beams (FIBs) are widely applied during manufacturing and for failure analysis, as a preparation tool for cross sectional scanning electron microscopy or for the extraction of lamellae for (scanning) transmission electron microscopy investigation of nanoelectronic devices. The impact of the ion beam milling on surface contamination is investigated by time-of-flight secondary ion mass spectroscopy, while the electrical surface damage is analyzed by a micro four-point probe. It is shown that the redeposition of milled Ga and Cu reaches levels below sensitivity (5 × 1010 at cm−2) at less than 10 mm from FIB structures while the lateral range of electrical surface damage is an order of magnitude smaller. The major source of the redeposition is the resputtering of sputtered material from the sample that was previously deposited on the SEM column. The 2D distribution of the redeposition is asymmetric and is simulated well based on a simplified model of the column and sample configuration. The electrical surface damage mainly relates to the beam tails. Pt deposits for surface protection require much lower Ga+ ion doses, and therefore have less impact on the wafer surface contamination. However, the range of electrical surface damage is larger for Pt deposits due to increased beam scattering in the low vacuum during the Pt deposition. With these contamination and damage levels and ranges, ‘wafer return’, i.e. continuing the wafer processing after the FIB, can be considered feasible for back-end of line processes with the loss of only the analyzed die or, potentially, also its neighbor. For front-end of line processes the acceptable contamination levels are more stringent and the feasibility of wafer return will be more process specific. (paper)

  13. Extraction of electron beam dose parameters from EBT2 film data scored in a mini phantom.

    Science.gov (United States)

    O'Reilly, Dedri; Smit, Cobus J L; du Plessis, Freek C P

    2013-09-01

    Quality assurance of medical linear accelerators includes dosimetric parameter measurement of therapeutic electron beams e.g. relative dose at a depth of 80% (R₈₀). This parameter must be within a tolerance of 0.2 cm of the declared value. Cumbersome water tank measurements can be regarded as a benchmark to measure electron depth dose curves. A mini-phantom was designed and built, in which a strip of GAFCHROMIC® EBT2 film could be encased tightly for electron beam depth dose measurement. Depth dose data were measured for an ELEKTA Sl25 MLC, ELEKTA Precise, and ELEKTA Synergy (Elekta Oncology Systems, Crawley, UK) machines. The electron beam energy range was between 4 and 22 MeV among the machines. A 10 × 10 cm² electron applicator with 95 cm source-surface-distance was used on all the machines. 24 h after irradiation, the EBT2 film strips were scanned on Canon CanoScan N670U scanner. Afterwards, the data were analysed with in-house developed software that entailed optical density to dose conversion, and optimal fitting of the PDD data to de-noise the raw data. From the PDD data R₈₀ values were solved for and compared with acceptance values. A series of tests were also carried out to validate the use of the scanner for film Dosimetry. These tests are presented in this study. It was found that this method of R₈₀ evaluation was reliable with good agreement with benchmark water tank measurements using a commercial parallel plate ionization chamber as the radiation detector. The EBT2 film data yielded R₈₀ values that were on average 0.06 cm different from benchmark water tank measured R₈₀ values. PMID:23794059

  14. Broad, intense, quiescent beam of singly charged metal ions obtained by extraction from self-sputtering plasma far above the runaway threshold

    Energy Technology Data Exchange (ETDEWEB)

    Anders, Andre; Oks, Efim

    2009-05-19

    Dense metal plasmas obtained by self-sputtering far above the runway threshold are well suited to generate intense quiescent ion beams. The dilemma of high current density and charge state purity can be solved when using target materials of low surface binding energy by utilizing non-resonant exchange reactions before ion extraction. Space-charge-limited quiescent beams of Cu+, Zn+, and Bi+ with ~;;10 mA/cm2 have been obtained through multi-aperture gridded ion extraction up to 45 kV from self-sputtering plasmas.

  15. The relationship between visible light emission and species fraction of the hydrogen ion beams extracted from 2.45 GHz microwave discharge

    CERN Document Server

    Cortázar, O D; Tarvainen, O; Kalvas, T; Koivisto, H

    2015-01-01

    The relationship between Balmer-α and Fulcher-band emissions with extracted H +, H+2 , and H+3 ions is demonstrated for a 2.45 GHz microwave discharge. Ion mass spectra and optical measurements of Balmer-α and Fulcher-band emissions have been obtained with a Wien Filter having an optical view-port on the plasma chamber axis. The beam of approximately 1 mA is analyzed for different plasma conditions simultaneously with the measurement of light emissions both with temporal resolution. The use of visible light emissions as a valuable diagnostic tool for monitoring the species fraction of the extracted beams is proposed.

  16. Use of a Bent Crystal with a Decreasing Curvature to Increase the Efficiency of the Extraction and Collimation of a Beam in an Accelerator

    OpenAIRE

    Yazynin, I. A.; Maisheev, V. A.; Chesnokov, Yu. A.

    2011-01-01

    It has been shown that the use of a bent crystal with a variable curvature radius makes it possible to reduce the fraction of dechanneled particles by an order of magnitude. This effect enables the strong reduction of the particle density at the edge of a collimator or the partition of a septum upon the multiturn extraction of a beam from a ring accelerator. In particular, the beam extraction efficiency at the U-70 synchrotron and Large Hadron Collider can be increased to 95 and 99.65%, respe...

  17. A Novel Eddy Current Septum Magnet for SPS Extraction towards LHC and CNGS

    CERN Document Server

    Schröder, G H; Carlier, E; Dieperink, J H; Ducimetière, L; Goddard, B; Lázár, C; Mayer, M; Vossenberg, Eugène B; Weterings, W

    2000-01-01

    A new East Fast-Extraction System is under construction in the SPS, to supply particles with a maximum batch length of 7.8 us and 10.5 us to the LHC and to CNGS (CERN Neutrino to Gran Sasso), respectively. The extraction septum magnets actually used at the SPS have been designed for slow extraction over several seconds, have large cooling and electrical power demands and need frequently maintenance in a high radiation environment. A fast system of only 250 us pulse duration has therefore been developed, using a half-sine excitation pulse with a superimposed third harmonic. The short pulse duration requires very thin magnetic yoke laminations, which can not easily be stamped and stacked. Profiting from a development for the LHC beam dump kicker magnets, the yoke is therefore built-up from tape-wound cylindrical cores, employing 50 um thick Si-steel tape. Thirty two cores are stacked longitudinally to produce a yoke of 3.2 meter length. The aperture is cut radial into each cylinder. The cores are radial compres...

  18. Measuring the energy parameters of the nanosecond electron beam extracted in air through a foil

    International Nuclear Information System (INIS)

    Comparison of the measurement results of energy densities and absorbed dose during the passage of electron beam with the energy of 300 keV, duration of 10 ns, current density of > 10 A/cm2 behind the acceleration foil in the air is conducted using different methods. The measurements have been carried out using compact nanosecond accelerator comprising a generator assembled according to the Marx scheme and vacuum diode with cold cathode operating in the regime of electron explosion emission. The current in the diode constituted approximately 3 kA, accelerating voltage - 350 kV. It is shown that during oscillographic measurements and the measurements according to the voltage upon the measurement capacitance considerable mistakes are possible which are conditioned by the electron wide spectrum. Results obtained using the calorimetric method which is especially convenient when determining absorbed doses in thin targets are the most objective ones

  19. EXTRACT

    DEFF Research Database (Denmark)

    Pafilis, Evangelos; Buttigieg, Pier Luigi; Ferrell, Barbra;

    2016-01-01

    The microbial and molecular ecology research communities have made substantial progress on developing standards for annotating samples with environment metadata. However, sample manual annotation is a highly labor intensive process and requires familiarity with the terminologies used. We have the...... and text-mining-assisted curation revealed that EXTRACT speeds up annotation by 15-25% and helps curators to detect terms that would otherwise have been missed.Database URL: https://extract.hcmr.gr/......., organism, tissue and disease terms. The evaluators in the BioCreative V Interactive Annotation Task found the system to be intuitive, useful, well documented and sufficiently accurate to be helpful in spotting relevant text passages and extracting organism and environment terms. Comparison of fully manual...

  20. Detailed beam and plasma measurements on the vessel for extraction and source plasma analyses (VESPA) Penning H⁻ ion source.

    Science.gov (United States)

    Lawrie, S R; Faircloth, D C; Letchford, A P; Whitehead, M O; Wood, T

    2016-02-01

    A vessel for extraction and source plasma analyses (VESPA) is operational at the Rutherford Appleton Laboratory (RAL). This project supports and guides the overall ion source R&D effort for the ISIS spallation neutron and muon facility at RAL. The VESPA produces 100 mA of pulsed H(-) beam, but perveance scans indicate that the source is production-limited at extraction voltages above 12 kV unless the arc current is increased. A high resolution optical monochromator is used to measure plasma properties using argon as a diagnostic gas. The atomic hydrogen temperature increases linearly with arc current, up to 2.8 eV for 50 A; whereas the electron temperature has a slight linear decrease toward 2.2 eV. The gas density is 10(21) m(-3), whilst the electron density is two orders of magnitude lower. Densities follow square root relationships with arc current, with gas density decreasing whilst electron (and hence ion) density increases. Stopping and range of ions in matter calculations prove that operating a high current arc with an argon admixture is extremely difficult because cathode-coated cesium is heavily sputtered by argon. PMID:26932004

  1. Detailed beam and plasma measurements on the vessel for extraction and source plasma analyses (VESPA) Penning H− ion source

    International Nuclear Information System (INIS)

    A vessel for extraction and source plasma analyses (VESPA) is operational at the Rutherford Appleton Laboratory (RAL). This project supports and guides the overall ion source R&D effort for the ISIS spallation neutron and muon facility at RAL. The VESPA produces 100 mA of pulsed H− beam, but perveance scans indicate that the source is production-limited at extraction voltages above 12 kV unless the arc current is increased. A high resolution optical monochromator is used to measure plasma properties using argon as a diagnostic gas. The atomic hydrogen temperature increases linearly with arc current, up to 2.8 eV for 50 A; whereas the electron temperature has a slight linear decrease toward 2.2 eV. The gas density is 1021 m−3, whilst the electron density is two orders of magnitude lower. Densities follow square root relationships with arc current, with gas density decreasing whilst electron (and hence ion) density increases. Stopping and range of ions in matter calculations prove that operating a high current arc with an argon admixture is extremely difficult because cathode-coated cesium is heavily sputtered by argon

  2. I. THE THEORY OF ABERRATIONS OF QUADRUPOLE FOCUSING ARRAYS. II. ION OPTICAL DESIGN OF HIGH QUALITY EXTRACTED SYNCHROTRON BEAMS WITH APPLICATION TO THE BEVATRON

    Energy Technology Data Exchange (ETDEWEB)

    Meads Jr., Philip Francis

    1963-05-15

    In Part One they formulate in a general way the problem of analyzing and evaluating the aberrations of quadrupole magnet beam systems, and of characterizing the shapes and other properties of the beam envelopes in the neighborhood of foci. They consider all aberrations, including those due to misalignments and faulty construction, through third order in small parameters, for quadrupole beam systems. One result of this study is the development of analytic and numerical techniques for treating these aberrations, yielding useful expressions for the comparison of the aberrations of different beam systems. A second result of this study is a comprehensive digital computer program that determines the magnitude and nature of the aberrations of such beam systems. The code, using linear programming techniques, will adjust the parameters of a beam system to obtain specified optical properties and to reduce the magnitude of aberrations that limit the performance of that system. They examine numerically, in detail, the aberrations of two typical beam systems. In Part Two, they examine the problem of extracting the proton beam from a synchrotron of 'H' type magnet construction. They describe the optical studies that resulted in the design of an external beam from the Bevatron that is optimized with respect to linear, dispersive, and aberration properties and that uses beam elements of conservative design. The design of the beam is the result of the collaboration of many people representing several disciplines. They describe the digital computer programs developed to carry out detailed orbit studies which were required because of the existence of large second order aberrations in the beam.

  3. Performance Limitations in the LHC due to Parasitic Beam-beam Encounters- Parameter Dependence, Scaling, and PACMAN Effects

    CERN Document Server

    Giachino, R; Metral, E; Papotti, G; Pieloni, T; Trad, G; Buffat, X; Kaltchev, D

    2013-01-01

    A novel type of 2.76 m long slotted, or perforated, strip-line pick-up, or kicker electrode structure, for CSRe stochastic cooling of non-relativistic particle beams with β~ 0.7 is presented. It is installed inside a bending vacuum chamber with the output signal taken from the downstream end. This slotted structure features a sufficiently broad bandwidth, good beam coupling impedance, low losses and a comparatively easy mechanical construction and installation into the CSRe dipole chamber. In this paper the electrode structure and pickup tank, as well as the beam test results will be presented.

  4. Negative ion production and beam extraction processes in a large ion source (invited)

    International Nuclear Information System (INIS)

    Recent research results on negative-ion-rich plasmas in a large negative ion source have been reviewed. Spatial density and flow distributions of negative hydrogen ions (H−) and positive hydrogen ions together with those of electrons are investigated with a 4-pin probe and a photodetachment (PD) signal of a Langmuir probe. The PD signal is converted to local H− density from signal calibration to a scanning cavity ring down PD measurement. Introduction of Cs changes the slope of plasma potential local distribution depending upon the plasma grid bias. A higher electron density H2 plasma locally shields the bias potential and behaves like a metallic free electron gas. On the other hand, the bias and extraction electric fields penetrate in a Cs-seeded electronegative plasma even when the electron density is similar. Electrons are transported by the penetrated electric fields from the driver region along and across the filter and electron deflection magnetic fields. Plasma ions exhibited a completely different response against the penetration of electric fields

  5. Negative ion production and beam extraction processes in a large ion source (invited)

    Energy Technology Data Exchange (ETDEWEB)

    Tsumori, K., E-mail: tsumori@nifs.ac.jp; Nakano, H.; Goto, M.; Nagaoka, K.; Osakabe, M.; Takeiri, Y.; Kaneko, O. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); The Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Ikeda, K.; Kisaki, M. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu 509-5292 (Japan); Geng, S. [The Graduate University for Advanced Studies, Shonan Village, Hayama, Kanagawa 240-0193 (Japan); Wada, M. [Graduate School of Science and Engineering, Doshisha University, Kyotanabe, Kyoto 610-0321 (Japan); Sasaki, K.; Nishiyama, S. [Division of Quantum Science and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Serianni, G.; Agostinetti, P.; Sartori, E.; Brombin, M.; Veltri, P. [Plasma Engineering Group, Consorzio RFX, Corso Stati Uniti 4, 35127 Padova (Italy); Wimmer, C. [Max-Planck-Institut für Plasmaphysik, Bereich ITER-Technologie und -Diagnostik/N-NBI Boltzmannstr. 2, 85748 Garching (Germany)

    2016-02-15

    Recent research results on negative-ion-rich plasmas in a large negative ion source have been reviewed. Spatial density and flow distributions of negative hydrogen ions (H{sup −}) and positive hydrogen ions together with those of electrons are investigated with a 4-pin probe and a photodetachment (PD) signal of a Langmuir probe. The PD signal is converted to local H{sup −} density from signal calibration to a scanning cavity ring down PD measurement. Introduction of Cs changes the slope of plasma potential local distribution depending upon the plasma grid bias. A higher electron density H{sub 2} plasma locally shields the bias potential and behaves like a metallic free electron gas. On the other hand, the bias and extraction electric fields penetrate in a Cs-seeded electronegative plasma even when the electron density is similar. Electrons are transported by the penetrated electric fields from the driver region along and across the filter and electron deflection magnetic fields. Plasma ions exhibited a completely different response against the penetration of electric fields.

  6. Performance of Advanced Light Source particle beam diagnostics

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS), a third-generation synchrotron radiation facility, is complete. The particle beam diagnostics have been installed and tested. The beam injection systems have been running for two years. We have performance data on beam position monitors, beam intensity monitors, scintillators, beam collimators, a 50 Ω Faraday cup, and broad-band striplines and kickers used in the linac, transport lines, and the booster synchrotron. The single-turn monitoring capability of the booster beam position monitoring system has been particularly useful for studying beam dynamics. Beam diagnostics for the storage ring are being commissioned. In this paper we describe each instrument, show its performance, and outline how the instruments are controlled and their output data displayed

  7. Statistical signal processing techniques for coherent transversal beam dynamics in synchrotrons

    Energy Technology Data Exchange (ETDEWEB)

    Alhumaidi, Mouhammad

    2015-03-04

    Transversal coherent beam oscillations can occur in synchrotrons directly after injection due to errors in position and angle, which stem from inaccurate injection kicker reactions. Furthermore, the demand for higher beam intensities is always increasing in particle accelerators. The wake fields generated by the traveling particles will be increased by increasing the beam intensity. This leads to a stronger interaction between the beam and the different accelerator components, which increases the potential of coherent instabilities. Thus, undesired beam oscillations will occur when the natural damping is not enough to attenuate the oscillations generated by the coherent beam-accelerator interactions. The instabilities and oscillations can be either in transversal or longitudinal direction. In this work we are concerned with transversal beam oscillations only. In normal operation, transversal beam oscillations are undesired since they lead to beam quality deterioration and emittance blow up caused by the decoherence of the oscillating beam. This decoherence is caused by the tune spread of the beam particles. The emittance blow up reduces the luminosity of the beam, and thus the collision quality. Therefore, beam oscillations must be suppressed in order to maintain high beam quality during acceleration. A powerful way to mitigate coherent instabilities is to employ a feedback system. A Transversal Feedback System (TFS) senses instabilities of the beam by means of Pickups (PUs), and acts back on the beam through actuators, called kickers. In this thesis, a novel concept to use multiple PUs for estimating the beam displacement at the position with 90 phase advance before the kicker is proposed. The estimated values should be the driving feedback signal. The signals from the different PUs are delayed such that they correspond to the same bunch. Subsequently, a weighted sum of the delayed signals is suggested as an estimator of the feedback correction signal. The

  8. Effects of combined treatments of electron-beam irradiation and addition of leek (Allium tuberosum) extract on reduction of pathogens in pork jerky.

    Science.gov (United States)

    Kang, Mingu; Kim, Hyun-Joo; Jayasena, Dinesh D; Bae, Young Sik; Yong, Hae In; Lee, Mooha; Jo, Cheorun

    2012-12-01

    This study investigated the combined effect of electron-beam irradiation and addition of leek (Allium tuberosum R.) extract on pork jerky inoculated with selected foodborne pathogens. Prepared pork jerky samples (control and samples with 1.0% leek extract) were inoculated with pathogens and subsequently irradiated at 0, 0.5, 1, 2, 3, and 4 kGy doses. In comparison with the control, samples with 1.0% leek extract showed significant reduction in the numbers of Escherichia coli, Listeria monocytogenes, and Salmonella Typhimurium. No viable counts were detected for Salmonella Typhimurium in both control and leek-extract samples, and for E. coli and L. monocytogenes in the leek-extract sample exposed to 3 kGy irradiation dose. The D(10) values for E. coli, L. monocytogenes, and Salmonella Typhimurium observed in the irradiated samples with leek extract were 0.39, 0.34, and 0.32 kGy, while the D(10) values in those without leek extract were 0.65, 0.65, and 0.39 kGy, respectively. Therefore, our results clearly showed that irradiation combined with leek extract was effective in reducing pathogens, suggesting that a low dose of irradiation combined with the addition of a natural antimicrobial agent can enhance the microbial safety and shelf-life of pork jerky. PMID:23199493

  9. Summary of Beam Vacuum Activities Held during the LHC 2008-2009 Shutdown

    CERN Document Server

    Bregliozzi, Giuseppe; Jimenez, Jose

    2010-01-01

    At the start of the CERN Large Hadron Collider (LHC) 2008-2009 shutdown, all the LHC experimental vacuum chambers were vented to neon atmosphere. They were later pumped down shortly before beam circulation. Meanwhile, 2.3 km of vacuum beam pipes with NEG coatings were vented to air to allow the installation or repair of several components such as roman pot, magnets kicker, collimators, rupture disks and masks and reactivated thereafter. Beside these standard operations, “fast exchanges” of vacuum components and endoscopies inside cryogenic beam vacuum chambers were performed. This paper presents a summary of all the beam vacuum activities held during this period and the achieved vacuum performances

  10. Development of a fast cyclotron gas stopper for intense rare isotope beams from projectile fragmentation: Study of ion extraction with a radiofrequency carpet

    Energy Technology Data Exchange (ETDEWEB)

    Bollen, Georg [Michigan State University; Morrissey, David [Michigan State University

    2011-01-16

    Research and development has been performed in support of the design of a future rare isotope beam facility in the US. An important aspect of plans for earlier RIA (Rare Isotope Accelerator) and a requirement of FRIB (Facility of Rare Isotope Beams) to be built at Michigan State University are the availability of so-called “stopped beams” for research that contributes to answering questions like how elements in the universe are created and to provide better insight into the nature of Fundamental Interactions. In order to create “stopped beams” techniques are required that transform fast rare isotopes beams as they are available directly after addresses questions like the origin of that will allow and High priority is given to the evaluation of intensity limitations and the efficiency of stopping of fast fragment beams in gas cells and to the exploration of options to increase the efficiency and the reduction of space charge effects. Systematic studies performed at MSU as part of the RIA R&D with a linear gas cell under conditions close to those expected at RIA and related simulations confirm that the efficiency of stopping and extracting ions decreases with increasing beam intensity. Similar results have also been observed at RIKEN in Japan. These results indicate the concepts presently under study will not be able to cover the full range of intensities of fast beams expected at RIA without major losses. The development of a more robust concept is therefore critical to the RIA concept. Recent new beam simulation studies performed at the NSCL show that the stopping of heavy ions in a weakly focusing gas-filled magnetic field can overcome the intensity limitation of present systems while simultaneously providing a much faster ion extraction. We propose to design and build such a cyclotron gas stopper and to test it at the NSCL under conditions as close as possible to those found at RIA.

  11. Improvement of microbiological safety and sensorial quality of pork jerky by electron beam irradiation and by addition of onion peel extract and barbecue flavor

    International Nuclear Information System (INIS)

    The combined effects of electron-beam (EB) irradiation and addition of onion peel (OP) extract and barbecue flavor (BF) on inactivation of foodborne pathogens and the quality of pork jerky was investigated. Prepared pork jerky samples were irradiated (0, 1, 2, and 4 kGy) and stored for 2 month at 25 °C. The D10 values of Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium observed in the OP treated samples were 0.19, 0.18, and 0.19 kGy, whereas those in control were 0.25, 0.23, and 0.20 kGy, respectively. Irradiated samples with OP extract and BF had substantially lower total aerobic bacterial counts than the control had. Samples with added OP extract and BF had lower peroxide values than the control had. Sensory evaluation indicated that overall acceptability of treated samples was not changed up to 2 kGy. Therefore, EB irradiation, combined with OP extract and BF, has improved the microbiological safety with no negative effects on the quality of pork jerky. - Highlights: • Electron-beam (EB) was applied to pork jerky to improve safety. • Onion peel extract (OP) was used synergistic effect on microbial reduction. • Barbecue flavor (BF) was introduced to achieve consistency of flavor. • EB with OP and BF improved safety without negative effects on quality of pork jerky

  12. The use of part of the energy of the extracted electron beam from the circular accelerator for the construction of a free electron laser

    International Nuclear Information System (INIS)

    The possibility of constructing the Free Electron Laser on the basis of Yerevan Physical Institute synchrotron is discussed. Advisability of constructing the FEL on the extracted electron beam in the linear mode is shown. It is noted that the construction of the FEL has no influence on carrying out fundamental investigations on the synchrotron as on an independent instrument because the FEL needs only 10-15% of the initial energy of the extracted electron beam. The necessity of constructing the FEL is proved for the long-wave - infrared - range (from 2 mm to 0.760 μm), taking into account the financial and technical manufacturing capability. This conclusion also results from the requirements of fundamental and applied tasks that propose investigations by means of infrared electromagnetic waves. The regional users of Yerevan FEL are shown

  13. Design, fabrication and RF characterization of broadband prototype kicker RF cavity for longitudinal multi bunch feedback system for Indus-2

    International Nuclear Information System (INIS)

    In Indus-2 storage ling, coupled bunch instabilities (CBI) may get generated due to irregularities in vacuum chambers and bellows, modes of septum chamber and RF cavities etc. Longitudinal multi bunch feedback system (LMBFS) will be installed, which will damp the longitudinal instabilities by sensing the oscillations generated due to instabilities and applying a corrective RF kick, The broadband kicker RF cavity will be a part of this feedback system. The operating frequency range of the kicker RF cavity has been chosen as 1264 MHz to 1517 MHz with a central frequency 1391 MHz and bandwidth of 253 MHz. Cavity design is based on the pillbox type with nose cone geometry for higher shunt impedance. Large bandwidth has been obtained by strongly loading a pillbox cavity with special ridged waveguides followed by broadband transitions to 7/8 inch coaxial lines, which are placed symmetrically with respect to the fundamental mode field distribution. Half of the coaxial feedthroughs are used as input power while the remaining as matched terminations. Simulated values of central frequency and bandwidth of the cavity are 1391 MHz and 253 MHz respectively, with loaded quality factor 5.5. S-parameters have been also calculated for entire bandwidth for cavity with eight feedthroughs. Simulations have been carried out with the help of computer code SUPERFISH and 3D-CST Studio Suite and important RF parameters of the cavity were worked out. A prototype aluminum cavity has been fabricated in two half shells. Some dimensional allowances has been kept for final tuning of the cavity. Eight feedthroughs are also designed, fabricated and mounted to test the cavity. Preliminary RF characterization has been carried out on the fabricated kicker cavity using two 4-port splitters and two set of three 2-ports splitters. The measured central frequency of the cavity is 1406 MHz with bandwidth of ∼ 250 MHz and loaded quality factor 5.8. S-parameters of the cavity were also measured. This paper

  14. Beam transfer functions and beam stabilisation in a double RF system

    CERN Document Server

    Shaposhnikova, Elena; Linnecar, Trevor Paul R

    2005-01-01

    The high intensity proton beam for LHC accelerated in the CERN SPS is stabilised against coupled-bunch instabilities by a 4th harmonic RF system in bunch-shortening mode. Bunch-lengthening mode, which could also be useful to reduce peak line density and alleviate problems from e-cloud and kicker heating, does not give desirable results for beam stability. In this paper an analysis of the limitations of these two different modes of operation is presented together with measurements of the Beam Transfer Function for the double RF system. As predicted by theory, for sufficiently long bunches with the same noise excitation, the measured amplitude of the beam response in bunchlengthening mode is an order of magnitude higher than that for bunch-shortening mode or for a single RF system.

  15. A waveguide overloaded cavity as longitudinal kicker for the DA{Phi}NE bunch-by-bunch feedback system

    Energy Technology Data Exchange (ETDEWEB)

    Gallo, A.; Boni, R.; Ghigo, A.; Marcellini, F.; Serio, M.; Zobov, M. [Instituto Nazionale de Fisica Nucleare, Frascati (Italy). Lab. Nazionale di Frascati

    1996-08-01

    The multibunch operation of DA{Phi}NE calls for a very efficient feedback system to damp the coupled-bunch longitudinal instabilities. A collaboration program among SLAC, LBL and LNF laboratories on this subject led to the development of a time domain, digital system based on digital signal processors that has been already successfully tested at ALS. The feedback chain ends with the longitudinal kicker, an electromagnetic structure capable of transferring the proper energy correction to each bunch. A cavity kicker for the DA{Phi}NE bunch-by-bunch longitudinal feedback system based on a pill-box loaded by six waveguides has been designed and a full-scale aluminium prototype has been fabricated at LNF. Both simulations and measurements have shown a peak shunt impedance of about 750 ohm and a bandwidth of about 220 MHz. The large shunt impedance allows to economize on the costly feedback power. Moreover, the damping waveguides drastically reduce the device HOM longitudinal and transverse impedances. One cavity pre ring will be sufficient to operate the machine up to 30 bunches while a second device per ring together with a feedback power improvement will be necessary to reach the ultimate current. (G.T.)

  16. Using the Orbit Tracking Code Z3CYCLONE to Predict the Beam Produced by a Cold Cathode PIG Ion Source for Cyclotrons under DC Extraction

    CERN Document Server

    Forringer, Edward

    2005-01-01

    Experimental measurements of the emittance and luminosity of beams produced by a cold-cathode Phillips Ionization Guage (PIG) ion source for cyclotrons under dc extraction are reviewed. (The source being studied is of the same style as ones that will be used in a series of 250 MeV proton cyclotrons being constructed for cancer therapy by ACCEL Inst, Gmbh, of Bergisch Gladbach, Germany.) The concepts of 'plasma boundary' and 'plasma temperature' are presented as a useful set of parameters for describing the initial conditions used in computational orbit tracking. Experimental results for r-pr and z-pz emittance are compared to predictions from the MSU orbit tracking code Z3CYCLONE with results indicating that the code is able to predict the beam produced by these ion sources with adequate accuracy such that construction of actual cyclotrons can proceed with reasonably prudent confidence that the cyclotron will perform as predicted.

  17. Proposal of the experiment on investigation of the (d, p) reaction at the extracted deuteron beam of the U-70 accelerator

    International Nuclear Information System (INIS)

    An experiment on the investigation of the A(d, p)X reaction at the extracted deuteron beam created at the Serpukhov U-70 accelerator is proposed. Precise measurements of the momentum spectra of protons emitted in the (d, p) reaction at an initial deuteron momenta of 20-40 GeV/c can give unique information on the deuteron short-range structure. A manifestation of contribution of non-nucleonic degrees of freedom in the deuteron is entirely possible over this energy range

  18. Improvement of microbiological safety and sensorial quality of pork jerky by electron beam irradiation and by addition of onion peel extract and barbecue flavor

    Science.gov (United States)

    Kim, Hyun-Joo; Jung, Samooel; Yong, Hae In; Bae, Young Sik; Kang, Suk Nam; Kim, Il Suk; Jo, Cheorun

    2014-05-01

    The combined effects of electron-beam (EB) irradiation and addition of onion peel (OP) extract and barbecue flavor (BF) on inactivation of foodborne pathogens and the quality of pork jerky was investigated. Prepared pork jerky samples were irradiated (0, 1, 2, and 4 kGy) and stored for 2 month at 25 °C. The D10 values of Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium observed in the OP treated samples were 0.19, 0.18, and 0.19 kGy, whereas those in control were 0.25, 0.23, and 0.20 kGy, respectively. Irradiated samples with OP extract and BF had substantially lower total aerobic bacterial counts than the control had. Samples with added OP extract and BF had lower peroxide values than the control had. Sensory evaluation indicated that overall acceptability of treated samples was not changed up to 2 kGy. Therefore, EB irradiation, combined with OP extract and BF, has improved the microbiological safety with no negative effects on the quality of pork jerky.

  19. Development of the IHEP booster beam injection system

    International Nuclear Information System (INIS)

    A brief description of the IHEP synchrotron booster injection system equipment is given and results of experiments on two-turn injection are presented. The circuit of kicker-magnet switching is provided. At linear accelerator current of 80 mA the two-turn injection ensured the accumulation of 1.3 x 1012 proton/booster cycle; the total (per 29 injection cycles into the main accelerator) intensity of the accelerated beam in the booster bunch exceeded 2 X 1013, which is far in excess of the needs of the U-70 accelerator presently

  20. Beam coupling impedance simulation and RF measurements of a passive extraction septum for particle absorbing in the CERN Proton Synchrotron

    CERN Document Server

    Persichelli, S

    2014-01-01

    We present a study of the beam coupling impedance due to trapped modes of a new protection septum that will be installed in the CERN Proton Synchrotron (PS) during the Long Shutdown 1 (LS1). The interaction between the particle field and the discontinuities inside the septum generates electromagnetic fields localized in a particular region inside the device. These resonances, producing narrow peaks in the coupling impedance, can be potential source of beam instabilities for high intensity particle accelerators like PS. The final outcome of these studies is the basis for the acceptance of the septum installation in section 15 of the PS ring.

  1. SUCCESSFUL BUNCHED BEAM STOCHASTIC COOLING IN RHIC.

    Energy Technology Data Exchange (ETDEWEB)

    BRENNAN, J.M.; BLASKIEWICZ, M.; SEVERINO, F.

    2006-06-23

    We report on a successful test of bunch-beam stochastic cooling in RHIC at 100 GeV. The cooling system is designed for heavy ions but was tested in the recent RHIC run which operated only with polarized protons. To make an analog of the ion beam a special bunch was prepared with very low intensity. This bunch had {approx}1.5 x 10{sup 9} protons, while the other 100 bunches contained {approx}1.2 x 10{sup 11} protons each. With this bunch a cooling time on the order 1 hour was observed through shortening of the bunch length and increase in the peak bunch current, together with a narrowing of the spectral line width of the Scottky power at 4 GHz. The low level signal processing electronics and the isolated-frequency kicker cavities are described.

  2. Changes on lipid profile in beef burgers prepared with Rosemary extract and submitted to e-beam processing

    International Nuclear Information System (INIS)

    Radiation processing has been employed in some countries as a mean of treatment to assure microbiological safety of meat and meat products. Use of antioxidants for preventing lipid oxidation has been applied in those products. The present study aimed at evaluating the protecting effects of rosemary extract on the lipid profile of irradiated beef burgers. The samples were prepared with 400 ppm of rosemary extract, irradiated at doses 0, 3.5 and 7 kGy, stored at - 20 deg C for 45 days and after this time, evaluated in regard to the oxidative stability of lipids (TBARS values) and lipid profile in a GC (Gas chromatography). Non-irradiated and non-rosemary extract samples were used as a control. TBARS values were of 0.3 and 1.1 mgTBARS/kg of sample for rosemary extract and control samples (without extract) irradiated at 3.5 kGy, respectively. At 7 kGy, TBARS values were of 0.6 and 1.3 mgTBARS/kg of samples for rosemary extract and control samples (without extract), respectively. Total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) did not change in beef burgers, although they showed small differences between the batches, this differences were not significant (P<0.05). The amounts of Trans fatty acid increased significantly (P<0.05) only when used irradiation dose of 7 kGy (0.86 g/100 g of sample). These results showed that the rosemary extract can avoid the developing of lipid oxidation and the irradiation processing did not change lipid profile in beef burgers. (author)

  3. Changes on lipid profile in beef burgers prepared with Rosemary extract and submitted to e-beam processing

    Energy Technology Data Exchange (ETDEWEB)

    Trindade, Reginaldo A.; Sabundjian, Ingrid T.; Nunes, Thaise C.F.; Rogovschi, Vladimir D.; Villavicencio, Anna Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Mancini-Filho, Jorge [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Ciencias Farmaceuticas. Lab. de Lipides]. E-mail: jmancini@usp.br

    2007-07-01

    Radiation processing has been employed in some countries as a mean of treatment to assure microbiological safety of meat and meat products. Use of antioxidants for preventing lipid oxidation has been applied in those products. The present study aimed at evaluating the protecting effects of rosemary extract on the lipid profile of irradiated beef burgers. The samples were prepared with 400 ppm of rosemary extract, irradiated at doses 0, 3.5 and 7 kGy, stored at - 20 deg C for 45 days and after this time, evaluated in regard to the oxidative stability of lipids (TBARS values) and lipid profile in a GC (Gas chromatography). Non-irradiated and non-rosemary extract samples were used as a control. TBARS values were of 0.3 and 1.1 mgTBARS/kg of sample for rosemary extract and control samples (without extract) irradiated at 3.5 kGy, respectively. At 7 kGy, TBARS values were of 0.6 and 1.3 mgTBARS/kg of samples for rosemary extract and control samples (without extract), respectively. Total saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) did not change in beef burgers, although they showed small differences between the batches, this differences were not significant (P<0.05). The amounts of Trans fatty acid increased significantly (P<0.05) only when used irradiation dose of 7 kGy (0.86 g/100 g of sample). These results showed that the rosemary extract can avoid the developing of lipid oxidation and the irradiation processing did not change lipid profile in beef burgers. (author)

  4. Development of a pepper-pot emittance meter for diagnostics of low-energy multiply charged heavy ion beams extracted from an ECR ion source

    Energy Technology Data Exchange (ETDEWEB)

    Nagatomo, T., E-mail: nagatomo@riken.jp; Kase, M.; Kamigaito, O.; Nakagawa, T. [Nishina Center for Accelerator Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Tzoganis, V. [Nishina Center for Accelerator Based Science, RIKEN, Wako, Saitama 351-0198 (Japan); Cockcroft Institute, Daresbury, Warrington WA4 4AD (United Kingdom); Department of Physics, University of Liverpool, Liverpool, Merseyside L69 3BX (United Kingdom)

    2016-02-15

    Several fluorescent materials were tested for use in the imaging screen of a pepper-pot emittance meter that is suitable for investigating the beam dynamics of multiply charged heavy ions extracted from an ECR ion source. SiO{sub 2} (quartz), KBr, Eu-doped CaF{sub 2}, and Tl-doped CsI crystals were first irradiated with 6.52-keV protons to determine the effects of radiation damage on their fluorescence emission properties. For such a low-energy proton beam, only the quartz was found to be a suitable fluorescent material, since the other materials suffered a decay in fluorescence intensity with irradiation time. Subsequently, quartz was irradiated with heavy {sup 12}C{sup 4+}, {sup 16}O{sup 4+}, and {sup 40}Ar{sup 11+} ions, but it was found that the fluorescence intensity decreased too rapidly to measure the emittance of these heavy-ion beams. These results suggest that a different energy loss mechanism occurs for heavier ions and for protons.

  5. Development of a pepper-pot emittance meter for diagnostics of low-energy multiply charged heavy ion beams extracted from an ECR ion source

    Science.gov (United States)

    Nagatomo, T.; Tzoganis, V.; Kase, M.; Kamigaito, O.; Nakagawa, T.

    2016-02-01

    Several fluorescent materials were tested for use in the imaging screen of a pepper-pot emittance meter that is suitable for investigating the beam dynamics of multiply charged heavy ions extracted from an ECR ion source. SiO2 (quartz), KBr, Eu-doped CaF2, and Tl-doped CsI crystals were first irradiated with 6.52-keV protons to determine the effects of radiation damage on their fluorescence emission properties. For such a low-energy proton beam, only the quartz was found to be a suitable fluorescent material, since the other materials suffered a decay in fluorescence intensity with irradiation time. Subsequently, quartz was irradiated with heavy 12C4+, 16O4+, and 40Ar11+ ions, but it was found that the fluorescence intensity decreased too rapidly to measure the emittance of these heavy-ion beams. These results suggest that a different energy loss mechanism occurs for heavier ions and for protons.

  6. Status of the LHC proton beam in the CERN SPS

    CERN Document Server

    Arduini, Gianluigi; Bohl, T; Collier, Paul; Cornelis, Karel; Höfle, Wolfgang; Linnecar, Trevor Paul R; Shaposhnikova, Elena; Tückmantel, Joachim; Wenninger, J

    2002-01-01

    During the 2000-2001 shutdown the SPS has undergone a major hardware upgrade to cope with its role of LHC injector. An impedance reduction campaign, improvements to the RF beam-control systems, and modifications to the injection kicker magnets and transverse feedback were the main items of this upgrade. By the end of the 2001 run, after a series of machine development sessions, a single LHC batch with half the nominal intensity could be accelerated from 26 to 450 GeV/c, the LHC injection energy, with nominal longitudinal and transverse parameters. At present the major known obstacle to the achievement of the nominal LHC beam with four batches is the beam-induced electron cloud. This generates both dramatic vacuum pressure increases and fast single and coupled bunch transverse instabilities. The problems encountered with this high brilliance beam and solutions developed so far are presented. Possible cures for the existing limitations are outlined.

  7. High precision pulse magnet power supply development for SACLA beam-line switch and pulse NMR measurement

    International Nuclear Information System (INIS)

    In order to achieve quasi-simultaneous operation of multi-XFEL beamlines, a pulse-by-pulse electron beam switching system has been developed at SACLA. In this system, a kicker magnet deflects the electron bunch, whose maximum repetition is 60 Hz, into three directions. The power supply for the kicker magnet generates trapezoidal current waveforms, whose polarity and amplitude can be flexibly changed. The stability of the pulsed current is found to be less than 11ppm. The magnetic field at a flat top (4ms) of the trapezoidal waveform is measured by using newly developed NMR system. The magnetic field stability better than 15ppm is confirmed with this NMR. In this paper, the design and development of the high-precision pulse power supply and the newly developed NMR system are described. (author)

  8. The beam dump tunnels

    CERN Multimedia

    Patrice Loïez

    2002-01-01

    In these images workers are digging the tunnels that will be used to dump the counter-circulating beams. Travelling just a fraction under the speed of light, the beams at the LHC will each carry the energy of an aircraft carrier travelling at 12 knots. In order to dispose of these beams safely, a beam dump is used to extract the beam and diffuse it before it collides with a radiation shielded graphite target.

  9. Beam-Beam Effects

    OpenAIRE

    Herr, W; Pieloni, T.

    2016-01-01

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

  10. Beam-Beam Effects

    CERN Document Server

    Herr, W

    2014-01-01

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

  11. Quadrupole slow-wave deflector for chopping charged-particle beams

    International Nuclear Information System (INIS)

    We introduce a new beam-deflector design for chopping low-energy charged-particle beams, the quadrupole slow-wave deflector (QSWD). This new design integrates the traveling-wave beam deflector, an electrostatic quadrupole, and clearing electrodes into a single compact structure. The four-electrode device performs ion clearing and linear focusing in the quadrupole (or transmit) mode, and also serves as a fast kicker in the deflecting mode. A QSWD operates with a constantly sustained electric field that sweeps off the ions and electrons produced by beam-gas scattering. Thus, a chopper using the QSWD can avoid beam neutralization with consequent emittance growth due to the beam-plasma interaction. We shall present the theoretical studies and the design considerations of the quadrupole deflector. A conceptual design of the chopper for a proposed Long Pulse Spallation Neutron Source (LPSS) at Los Alamos will be given as an example. (author)

  12. Study of X-Ray and $\\gamma$-Ray Spectra from Antiprotonic Atoms at the Slowly Extracted Antiproton Beam of LEAR

    CERN Multimedia

    2002-01-01

    This experiment will study the X-ray spectra of antiprotonic atoms and the $\\gamma$ spectra of residual nuclei after the antiproton absorption. We intend to begin with measurements on selected isotopically pure targets. Strong interaction effects, the antiproton absorption and the atomic cascade are analysed through the measurement of energies, lineshapes, relative and absolute intensities of all observable lines. The experiments are continued to determine st in resolved fine structure levels and in different isotopes of the same element. Coincidence techniques may be applied. All components of the experimental set-up are already existing from previous experiments and we could begin the measurements with any slowly extracted beam of low energy at LEAR.

  13. V123 Beam Synchronous Encoder Module

    International Nuclear Information System (INIS)

    The V123 Synchronous Encoder Module transmits events to distributed trigger modules and embedded decoders around the RHIC rings where they are used to provide beam instrumentation triggers [1,2,3]. The RHIC beam synchronous event link hardware is mainly comprised of three VMEbus board designs, the central input modules (V201), and encoder modules (V123), and the distributed trigger modules (V124). Two beam synchronous links, one for each ring, are distributed via fiberoptic and fanned out via twisted wire pair cables. The V123 synchronizes with the RF system clock derived from the beam bucket frequency and a revolution fiducial pulse. The RF system clock is used to create the beam synchronous event link carrier and events are synchronized with the rotation fiducial. A low jitter RF clock is later recovered from this carrier by phase lock loops in the trigger modules. Prioritized hardware and software triggers fill up to 15 beam event code transmission slots per revolution while tracking the ramping RF acceleration frequency and storage frequency. The revolution fiducial event is always the first event transmitted which is used to synchronize the firing of the abort kicker and to locate the first bucket for decoders distributed about the ring

  14. Detailed beam and plasma measurements on the vessel for extraction and source plasma analyses (VESPA) Penning H{sup −} ion source

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, S. R., E-mail: scott.lawrie@stfc.ac.uk [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell, Oxford (United Kingdom); John Adams Institute of Accelerator Science, University of Oxford, Oxford (United Kingdom); Faircloth, D. C.; Letchford, A. P.; Whitehead, M. O.; Wood, T. [STFC ISIS Pulsed Spallation Neutron and Muon Facility, Rutherford Appleton Laboratory, Harwell, Oxford (United Kingdom)

    2016-02-15

    A vessel for extraction and source plasma analyses (VESPA) is operational at the Rutherford Appleton Laboratory (RAL). This project supports and guides the overall ion source R&D effort for the ISIS spallation neutron and muon facility at RAL. The VESPA produces 100 mA of pulsed H{sup −} beam, but perveance scans indicate that the source is production-limited at extraction voltages above 12 kV unless the arc current is increased. A high resolution optical monochromator is used to measure plasma properties using argon as a diagnostic gas. The atomic hydrogen temperature increases linearly with arc current, up to 2.8 eV for 50 A; whereas the electron temperature has a slight linear decrease toward 2.2 eV. The gas density is 10{sup 21} m{sup −3}, whilst the electron density is two orders of magnitude lower. Densities follow square root relationships with arc current, with gas density decreasing whilst electron (and hence ion) density increases. Stopping and range of ions in matter calculations prove that operating a high current arc with an argon admixture is extremely difficult because cathode-coated cesium is heavily sputtered by argon.

  15. SU-D-BRA-07: A Phantom Study to Assess the Variability in Radiomics Features Extracted From Cone-Beam CT Images

    Energy Technology Data Exchange (ETDEWEB)

    Fave, X; Fried, D [UT MD Anderson Cancer Center, Houston, TX (United States); UT Health Science Center Graduate School of Biomedical Sciences, Houston, TX (United States); Zhang, L; Yang, J; Balter, P; Followill, D; Gomez, D; Jones, A; Stingo, F; Court, L [UT MD Anderson Cancer Center, Houston, TX (United States)

    2015-06-15

    Purpose: Several studies have demonstrated the prognostic potential for texture features extracted from CT images of non-small cell lung cancer (NSCLC) patients. The purpose of this study was to determine if these features could be extracted with high reproducibility from cone-beam CT (CBCT) images in order for features to be easily tracked throughout a patient’s treatment. Methods: Two materials in a radiomics phantom, designed to approximate NSCLC tumor texture, were used to assess the reproducibility of 26 features. This phantom was imaged on 9 CBCT scanners, including Elekta and Varian machines. Thoracic and head imaging protocols were acquired on each machine. CBCT images from 27 NSCLC patients imaged using the thoracic protocol on Varian machines were obtained for comparison. The variance for each texture measured from these patients was compared to the variance in phantom values for different manufacturer/protocol subsets. Levene’s test was used to identify features which had a significantly smaller variance in the phantom scans versus the patient data. Results: Approximately half of the features (13/26 for material1 and 15/26 for material2) had a significantly smaller variance (p<0.05) between Varian thoracic scans of the phantom compared to patient scans. Many of these same features remained significant for the head scans on Varian (12/26 and 8/26). However, when thoracic scans from Elekta and Varian were combined, only a few features were still significant (4/26 and 5/26). Three features (skewness, coarsely filtered mean and standard deviation) were significant in almost all manufacturer/protocol subsets. Conclusion: Texture features extracted from CBCT images of a radiomics phantom are reproducible and show significantly less variation than the same features measured from patient images when images from the same manufacturer or with similar parameters are used. Reproducibility between CBCT scanners may be high enough to allow the extraction of

  16. SU-D-BRA-07: A Phantom Study to Assess the Variability in Radiomics Features Extracted From Cone-Beam CT Images

    International Nuclear Information System (INIS)

    Purpose: Several studies have demonstrated the prognostic potential for texture features extracted from CT images of non-small cell lung cancer (NSCLC) patients. The purpose of this study was to determine if these features could be extracted with high reproducibility from cone-beam CT (CBCT) images in order for features to be easily tracked throughout a patient’s treatment. Methods: Two materials in a radiomics phantom, designed to approximate NSCLC tumor texture, were used to assess the reproducibility of 26 features. This phantom was imaged on 9 CBCT scanners, including Elekta and Varian machines. Thoracic and head imaging protocols were acquired on each machine. CBCT images from 27 NSCLC patients imaged using the thoracic protocol on Varian machines were obtained for comparison. The variance for each texture measured from these patients was compared to the variance in phantom values for different manufacturer/protocol subsets. Levene’s test was used to identify features which had a significantly smaller variance in the phantom scans versus the patient data. Results: Approximately half of the features (13/26 for material1 and 15/26 for material2) had a significantly smaller variance (p<0.05) between Varian thoracic scans of the phantom compared to patient scans. Many of these same features remained significant for the head scans on Varian (12/26 and 8/26). However, when thoracic scans from Elekta and Varian were combined, only a few features were still significant (4/26 and 5/26). Three features (skewness, coarsely filtered mean and standard deviation) were significant in almost all manufacturer/protocol subsets. Conclusion: Texture features extracted from CBCT images of a radiomics phantom are reproducible and show significantly less variation than the same features measured from patient images when images from the same manufacturer or with similar parameters are used. Reproducibility between CBCT scanners may be high enough to allow the extraction of

  17. LHC Beam Vacuum During 2011 Machine Operation

    CERN Document Server

    Lanza, G; Bregliozzi, G; Jimenez, J M

    2012-01-01

    During the year 2011 the LHC operated for 682 fills, meaning 247 days and 2 hours of stable beam in total. From 368 bunches per beam at 150 ns bunch spacing circulating in the ring in December 2010, the 2011 proton physic ended with 1380 bunches per beam circulating with 50 ns bunch spacing. The machine performances increased in parallel with the vacuum improvement thanks to a well performed scrubbing run in April 2011 and a continuous conditioning of the beam pipes while the machine was running. The 2011 LHC operation ended with one month of ions physic runs. During the machine operation various phenomena of beam - vacuum interaction were detected, analyzed and solved. This paper describes the pressure behaviour along the machine layout and mainly in specific components position like the TDI (Target Dump Injection) and the MKI injector kickers. The “pressure spike” phenomena near the experiment CMS and in some Dipole 1 (D1) regions are discussed. Finally, results obtained during the 25 ns machine develop...

  18. Application of Chebyshev Formalism to Identify Nonlinear Magnetic Field Components in Beam Transport Systems

    Energy Technology Data Exchange (ETDEWEB)

    Spata, Michael [Old Dominion Univ., Norfolk, VA (United States)

    2012-08-01

    An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a beam-based technique for characterizing the extent of the nonlinearity of the magnetic fields of a beam transport system. Horizontally and vertically oriented pairs of air-core kicker magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the beam orbit relative to the unperturbed reference orbit. Fourier decomposition of the position data at eight different points along the beamline was then used to measure the amplitude of these frequencies. For a purely linear transport system one expects to find solely the frequencies that were applied to the kickers with amplitudes that depend on the phase advance of the lattice. In the presence of nonlinear fields one expects to also find harmonics of the driving frequencies that depend on the order of the nonlinearity. Chebyshev polynomials and their unique properties allow one to directly quantify the magnitude of the nonlinearity with the minimum error. A calibration standard was developed using one of the sextupole magnets in a CEBAF beamline. The technique was then applied to a pair of Arc 1 dipoles and then to the magnets in the Transport Recombiner beamline to measure their multipole content as a function of transverse position within the magnets.

  19. Characteristic X-ray radiation excited by 450 MeV/nucleon C+6 ions and 1.3 GeV protons in extracted and circulated beams of accelerator U70

    Science.gov (United States)

    Afonin, A. G.; Britvich, G. I.; Chesnokov, Yu. A.; Durum, A. A.; Kostin, M. Yu.; Maisheev, V. A.; Pikalov, V. A.; Savin, D. A.; Yanovich, A. A.; Kubankin, A. S.; Nazhmudinov, R. M.; Shul'ga, N. F.; Uglov, S. R.; Shchagin, A. V.

    2015-07-01

    The results of the experimental observation of characteristic X-ray radiation (CXR) excited in solid targets by the extracted and circulated 450 MeV/u C+6 ions beams and circulating 1.3 GeV protons beam are presented. The spectra of X-ray radiation measured from different targets are presented and discussed. It was found that the background radiation near the beams is low enough that allows the observation of the CXR spectral peaks with energies from a few to tens keV by semiconductor X-ray detectors. Applications of the CXR for monitoring of the number of accelerated particles in experimental applied and basic research, including radiobiology and radiation medicine as well as the relativistic nuclear physics and steering of beams by bent crystalline deflectors are proposed.

  20. Characteristic X-ray radiation excited by 450 MeV/nucleon C{sup +6} ions and 1.3 GeV protons in extracted and circulated beams of accelerator U70

    Energy Technology Data Exchange (ETDEWEB)

    Afonin, A.G.; Britvich, G.I.; Chesnokov, Yu.A.; Durum, A.A.; Kostin, M.Yu.; Maisheev, V.A.; Pikalov, V.A.; Savin, D.A.; Yanovich, A.A. [Institute for High Energy Physics in National Research Centre “Kurchatov Institute”, Protvino 142281 (Russian Federation); Kubankin, A.S.; Nazhmudinov, R.M. [Belgorod State University, Belgorod (Russian Federation); Shul’ga, N.F. [Kharkov Institute of Physics and Technology, Kharkov (Ukraine); Kharkov National University, Kharkov (Ukraine); Uglov, S.R. [Tomsk Polytechnic University, Tomsk (Russian Federation); Shchagin, A.V. [Belgorod State University, Belgorod (Russian Federation); Kharkov Institute of Physics and Technology, Kharkov (Ukraine)

    2015-07-15

    The results of the experimental observation of characteristic X-ray radiation (CXR) excited in solid targets by the extracted and circulated 450 MeV/u C{sup +6} ions beams and circulating 1.3 GeV protons beam are presented. The spectra of X-ray radiation measured from different targets are presented and discussed. It was found that the background radiation near the beams is low enough that allows the observation of the CXR spectral peaks with energies from a few to tens keV by semiconductor X-ray detectors. Applications of the CXR for monitoring of the number of accelerated particles in experimental applied and basic research, including radiobiology and radiation medicine as well as the relativistic nuclear physics and steering of beams by bent crystalline deflectors are proposed.

  1. A Kicker Pulse Generator for Measurement of the Tune and Dynamic Aperture in the LHC

    CERN Document Server

    Carlier, E; Vossenberg, E

    2007-01-01

    The large hadron collider (LHC) at CERN will be equipped with fast pulsed two-function magnets, which will be part of the measurement system for the tune and the dynamic aperture. For the tune measurement, the magnets will excite coherent oscillations of part of the beam. This is achieved by means of a generator producing a 5.1 mus base half-sine pulse of 1.2 kA amplitude, superimposed with a 3rd harmonic to produce a -2 mus flat top. A kick repetition rate of 2 Hz is possible. The maximum generator voltage is 3.3 kV, with a dynamic range of about 20. A 5.2 kV press-pack capsule IGBT is used as switching element. A fast 30 A gate driver is used for triggering. The generator pulse current interruption is obtained with an extra-fast small recovery series diode. Several advantages of the press-pack IGBT construction with respect to conventional IGBT modules will be discussed. To measure the dynamic aperture of the LHC at different beam energies, the same magnets will also be driven by a more powerful generator w...

  2. Digital transverse beam dampers from the Brookhaven AGS

    International Nuclear Information System (INIS)

    A wide band, digital damper system has been developed and is in use at the Brookhaven Alternating Gradient Synchrotron (AGS). The system consists of vertical and horizontal capacitive pickups, analog and digital processing electronics, four 500 Watt wide band power amplifiers, and two pairs of strip line beam kickers. The system is currently used to damp transverse coherent instabilities and injection errors, in both planes, for protons and all species of heavy ions. This paper discusses the system design and operation, particularly with regard to stabilization of the high intensity proton beam. The analog and digital signal processing techniques used to achieve optimum results are discussed. Operational data showing the effect of the damping are presented

  3. 3D terahertz beam profiling

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Strikwerda, Andrew; Wang, Tianwu;

    2013-01-01

    We present a characterization of THz beams generated in both a two-color air plasma and in a LiNbO3 crystal. Using a commercial THz camera, we record intensity images as a function of distance through the beam waist, from which we extract 2D beam profiles and visualize our measurements into 3D beam...

  4. CFD Study of the Hydrocarbon Boost Low-Pressure Inducer and Kicker in the Presence of a Circumferential Groove

    Science.gov (United States)

    Coker, Robert

    2011-01-01

    Results are presented of a computational fluid dynamics (CFD) study done in support of Marshall Space Flight Center's (MSFC) sub-scale water flow experiments of the Hydrocarbon Boost (HCB) Oxidizer Turbopump (OTP) being developed by the Air Force Research Laboratory (AFRL) and Aerojet. A circumferential groove may be added to the pump to reduce synchronous cavitation and subsequent bearing loads at a minimal performance cost. However, the energy may reappear as high order cavitation (HOC) that spans a relatively large frequency range. Thus, HOC may have implications for the full-scale OTP inducer in terms of reduced structural margin at higher mode frequencies. Simulations using the LOCI/Stream CFD program were conducted in order to explore the fluid dynamical impact of the groove on the low-pressure inducer and kicker. It was found that the circumferential groove has minimal head performance impact, but causes back-flowing high-swirl fluid to interact with the nearly-axial incoming fluid just above the inducer blades. The high-shear interface between the fluids is Kelvin-Helmholtz unstable, resulting in trains of low pressure regions or 'pearls' forming near the upstream edge of the groove. When the static pressure in these regions becomes low enough and they get cut by the blade leading edge, HOC is thought to occur. Although further work is required, the numerical models indicate that HOC will occur in the runbox of the AFRL/Aerojet HCB OTP. Comparisons to the ongoing water flow experiments will be discussed, as well as possible designs that may mitigate HOC while continuing to reduce synchronous cavitation. December 2011 MSS/LPS/SPS Joint Subcommittee Meeting ABSTRACT SUBMITTAL FORM

  5. Intense pulsed neutron source (IPNS-I) accelerator 500 MeV fast kickers

    International Nuclear Information System (INIS)

    Two ferrite loaded picture frame magnets with a kick of up to 15 mrad each are used to extract 500 MeV protons from the IPNS-I accelerator to the neutron source target at the Argonne National Laboratory. The magnet aperture is 10 cm wide by 5 cm high and the length is 60 cm. The single bunch extraction requires a magnetic field rise time (0 to 100%) of 90 ns and a flattop of 100 ns. The magnets receive the 3600 A maximum current via an array of 50 Ω coaxial cables connected in a shunt arrangement. The two legs of each magnet are energized with separate lines to keep the potential to ground to less than 40 kV. The system is designed to run at 30 pulses per second repetition rate. The complete system of control electronics, power supply, deuterium thyratron switch, magnet and resistive load will be described along with some of the problems of stray inductances and the techniques used to reduce them

  6. Specification for the power supply for tune kicker magnets of the synchrotron accelerator

    CERN Document Server

    Crescenti, M; Metzmacher, K; Sermeus, L; CERN. Geneva. AB Department

    2003-01-01

    A synchrotron machine, capable to accelerate either light ions or protons, will be the basic instrument of the CNA (Centro Nazionale di Adroterapia), the medical centre dedicated to the cancer therapy, that will be built in Italy in the near future. The machine complex consists of one proton-carbon-ion linac that will accelerate the particles up to an energy of 7 MeV/u. An injection line will transport them to the synchrotron ring where the injected particles will be accelerated and extracted with an energy ranging from 60 to 250 MeV for protons and from 120 to 400 MeV/u for carbon ions. Fig. 1 shows a preliminary schematic picture of the CNA medical centre.

  7. Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels

    CERN Document Server

    Rakhno, I L; Mokhov, N V; Sidorov, V I; Tropin, I S

    2012-01-01

    Currently a fast vertical 1.08-m long kicker (notcher) located in the Fermilab Booster Long-5 straight section is used to remove 3 out of 84 circulating bunches after injection to generate an abort gap. With magnetic field of 72.5 Gauss it removes only 87% of the 3-bunch intensity at 400 MeV, with 75% loss on pole tips of the focusing Booster magnets, 11% on the Long-6 collimators, and 1% in the rest of the ring. We propose to improve the notching efficiency and reduce beam loss in the Booster by using two horizontal kickers in the Long-12 section. The STRUCT calculations show that using such horizontal notchers, one can remove up to 99% of the 3-bunch intensity at 400-700 MeV, directing 96% of it to a new beam dump at the Long-13 section. This fully decouples notching and collimation. The beam dump absorbs most of the impinging proton energy in its jaws. The latter are encapsulated into an appropriate radiation shielding that reduces impact on the machine components, personnel and environment to the tolerabl...

  8. Improving the Fermilab Booster Notching Efficiency, Beam Losses and Radiation Levels

    Energy Technology Data Exchange (ETDEWEB)

    Rakhno, I.L.; Drozhdin, A.I.; Mokhov, N.V.; Sidorov, V.I.; Tropin, I.S.; /Fermilab

    2012-05-14

    A fast vertical 1.08-m long kicker (notcher) located in the Fermilab Booster Long-05 straight section is currently used to remove 3 out of 84 circulating bunches after injection to generate an abort gap. With the maximum magnetic field of 72.5 Gauss, it removes only 87% of the 3-bunch intensity at 400 MeV, with 75% loss on pole tips of the focusing Booster magnets, 11% on the Long-06 collimators, and 1% in the rest of the ring. We propose to improve the notching efficiency and reduce beam loss in the Booster by using three horizontal kickers in the Long-12 section. STRUCT calculations show that using horizontal notchers, one can remove up to 96% of the 3-bunch intensity at 400-700 MeV, directing 95% of it to a new beam dump at the Long-13 section. This fully decouples notching and collimation. The beam dump absorbs most of the impinging proton energy in its jaws. The latter are encapsulated into an appropriate radiation shielding that reduces impact on the machine components, personnel and environment to the tolerable levels. MARS simulations show that corresponding prompt and residual radiation levels can be reduced ten times compared to the current ones.

  9. Beam-beam effects

    Energy Technology Data Exchange (ETDEWEB)

    Zholents, A.

    1994-12-01

    The term beam-beam effects is usually used to designate different phenomena associated with interactions of counter-rotating beams in storage rings. Typically, the authors speak about beam-beam effects when such interactions lead to an increase of the beam core size or to a reduction of the beam lifetime or to a growth of particle`s population in the beam halo and a correspondent increase of the background. Although observations of beam-beam effects are very similar in most storage rings, it is very likely that every particular case is largely unique and machine-dependent. This constitutes one of the problems in studying the beam-beam effects, because the experimental results are often obtained without characterizing a machine at the time of the experiment. Such machine parameters as a dynamic aperture, tune dependencies on amplitude of particle oscillations and energy, betatron phase advance between the interaction points and some others are not well known, thus making later analysis uncertain. The authors begin their discussion with demonstrations that beam-beam effects are closely related to non linear resonances. Then, they will show that a non linearity of the space charge field is responsible for the excitation of these resonances. After that, they will consider how beam-beam effects could be intensified by machine imperfections. Then, they will discuss a leading mechanism for the formation of the beam halo and will describe a new technique for beam tails and lifetime simulations. They will finish with a brief discussion of the coherent beam-beam effects.

  10. ESTB: A New Beam Test Facility at SLAC

    Energy Technology Data Exchange (ETDEWEB)

    Pivi, M.; Fieguth, T.; Hast, C.; Iverson, R.; Jaros, J.; Jobe, K.; Keller, L.; Walz, D.; Weathersby, S.; Woods, M.; /SLAC

    2011-04-05

    End Station A Test Beam (ESTB) is a beam line at SLAC using a small fraction of the bunches of the 13.6 GeV electron beam from the Linac Coherent Light Source (LCLS), restoring test beam capabilities in the large End Station A (ESA) experimental hall. ESTB will provide one of a kind test beam essential for developing accelerator instrumentation and accelerator R&D, performing particle and particle astrophysics detector research, linear collider machine and detector interface (MDI) R&D studies, development of radiation-hard detectors, and material damage studies with several distinctive features. In the past, 18 institutions participated in the ESA program at SLAC. In stage I, 4 new kicker magnets will be added to divert 5 Hz of the LCLS beam to the A-line. A new beam dump will be installed and a new Personnel Protection System (PPS) is being built in ESA. In stage II, a secondary hadron target will be installed, able to produce pions up to about 12 GeV/c at 1 particle/pulse.

  11. Extraction from the CERN SPS

    CERN Document Server

    Baconnier, Yves; Kissler, Karl Heinz; de Raad, Bastiaan; Scandale, Walter

    1977-01-01

    The experimental programme requires three different modes of extraction from the SPS: fast extraction (burst duration from 3 mu s to 23 mu s), slow resonant extraction (spill duration 0.5 s to 2 s) and fast resonant extraction (spill duration shorter than 3 ms). All three modes have been successfully tested and brought into operation. Fast extraction of the full beam is 100% efficient. By fast beam shaving, fractions as low as 1% of the circulating beam can be extracted as low as 1% of the circulating beam can be extracted in a fairly stable way. Third-integer extraction is used to produce slow spills of 700 ms or more. The efficiency of resonant extraction is currently some 97%. (0 refs).

  12. LS1 Report: alive and kicking!

    CERN Multimedia

    Katarina Anthony

    2014-01-01

    Following eleven months of meticulous maintenance and consolidation works, the LHC's extraction kicker magnets (MKDs) and its pulse generators are back in the accelerator for a new phase of tests. Used to dump the beam, these kicker magnets are essential for the safety of the machine.   Pulse generators for the extraction kicker magnets at Point 6. The high voltage cables leading to the magnets can be seen in red. The LHC's kicker magnets are something rather special. Unlike most of the accelerator's extraction magnets, they only operate for a short period of time and focus on providing a quick "kick" to deflect the beam. If fact, they are permanently under voltage to be ready to go, and have only 3 microseconds in order to establish their kicking pulse! This means they have to be very powerful - with the help of their own high-powered pulse generators - and extremely well in synch - with the help of control and electronic specialists. "Du...

  13. Determination of intensity and position of the extracted electron beam at ELSA by means of high-frequency resonators; Bestimmung von Intensitaet und Position des extrahierten Elektronenstrahls an ELSA mittels Hochfrequenzresonatoren

    Energy Technology Data Exchange (ETDEWEB)

    Pusch, Thorsten

    2012-06-15

    The electron stretcher facility ELSA provides an electron beam of a few hundred pA used for the generation of bremsstrahlung photons probing the nucleon structure in a detector setup. For the correct interpretation of the events registered, the persistence of the beam position over time is crucial. Its continuous monitoring has been enabled by setting up a measurement system based on resonant cavities. Position signals at a frequency of 1.5 GHz and below one aW of power can be abstracted from the beam without degrading its quality. After frequency down-conversion to a few kHz, a narrow bandwidth detection performed by lock-in amplifiers separates them from noise. A maximum sample rate of 9 Hz and a resolution of one tenth of a millimeter could be achieved. The position signals have to be normalized to the beam current which is monitored by another dedicated resonator. The measurement precision down to a few pA allows for the accelerator extraction mechanism to be controlled by a feedback loop in order to obtain the respective requested current. (orig.)

  14. LEAR: antiproton extraction lines

    CERN Multimedia

    Photographic Service

    1992-01-01

    Antiprotons, decelerated in LEAR to a momentum of 100 MeV/c (kinetic energy of 5.3 MeV), were delivered to the experiments in an "Ultra-Slow Extraction", dispensing some 1E9 antiprotons over times counted in hours. Beam-splitters and a multitude of beam-lines allowed several users to be supplied simultaneously.

  15. Maintenance of raw and cooked ready-to-eat product quality of infused poultry meats with selected plant extracts during electron beam irradiation and after storage

    Science.gov (United States)

    Rababah, Taha

    The purpose of this study included: preparing plant extracts and evaluating these extracts for total phenolics and antioxidant activities (AA); infusing extract/combination that demonstrates superior AA into chicken breast and irradiating at 3.0 kGy; evaluating the physicochemical properties of irradiated and non-irradiated raw and cooked chicken breast at 5°C for 12 days and -20°C for 9 months; and selecting the extracts that demonstrated desirable AA, infusing these extracts into chicken breast and evaluating head-space volatiles, and conducting sensory evaluation. The total phenolic content and AA of the plant extracts ranged from 24.8 to 92.5 mg/g dry material (conjugated diene of methyl linoleate) and 3.4 to 86.3%, respectively. The AA of plant extracts using oxidative stability instrument were 4.6 to 10.2 h (Induction time). Green tea and grape seed extracts had the highest AA within several plant extracts, and were selected to retard lipid oxidation in further studies. Fresh boneless and skinless chicken breast meats were vacuum infused with varying concentrations of antioxidants: Green tea and grape seed extracts alone/in combination and tert-butylhydroquinone. The results showed that irradiation had no significant effect on pH, water holding capacity, but increased the redness and carbonyls in raw meats (p TBARS, hexanal, and pentanal values in raw and cooked meats. Addition of plant extracts decreased the amount of TBARS, hexanal, pentanal, and carbonyl values. Similar results were observed when the samples were stored at -20°C for 9 months. Descriptive sensory flavor results showed that irradiation did not affect the flavor attributes. Consumer, descriptive, and instrumental results showed that irradiation increased toughness, green tea improved the meat color, and the panel indicated that irradiation decreased the tenderness of the samples. Infusion of extracts/combinations into chicken meats increased lightness and decreased redness as well as the

  16. Cold and Slow Molecular Beam

    OpenAIRE

    Rasmussen, Julia; Patterson, Dave; Lu, Hsin-I; Wright, Matthew; Doyle, John M.

    2011-01-01

    Employing a two-stage cryogenic buffer gas cell, we produce a cold, hydrodynamically extracted beam of calcium monohydride molecules with a near effusive velocity distribution. Beam dynamics, thermalization and slowing are studied using laser spectroscopy. The key to this hybrid, effusive-like beam source is a “slowing cell” placed immediately after a hydrodynamic, cryogenic source [Patterson et al., J. Chem. Phys., 2007, 126, 154307]. The resulting CaH beams are created in two regimes. In on...

  17. Errors in beam channels and their correction

    International Nuclear Information System (INIS)

    Error alignment-effecting of the beam magnet elements (with taking into account the geodesic procedures of installation) and their regimes to beam characteristics are considered. The obtained expressions allow to estimate the changing ranges of beam parameters and choose the optimum correction systems of optic axis and beam envelope during the beams design stage. The results are illustrated on example of transport of UNK proton beam extracted from accelerator. 4 refs.; 5 figs

  18. Pulse-by-pulse multi-beam-line operation for x-ray free-electron lasers

    Science.gov (United States)

    Hara, Toru; Fukami, Kenji; Inagaki, Takahiro; Kawaguchi, Hideaki; Kinjo, Ryota; Kondo, Chikara; Otake, Yuji; Tajiri, Yasuyuki; Takebe, Hideki; Togawa, Kazuaki; Yoshino, Tatsuya; Tanaka, Hitoshi; Ishikawa, Tetsuya

    2016-02-01

    The parallel operation of plural undulator beam lines is an important means of improving the efficiency and usability of x-ray free-electron laser facilities. After the installation of a second undulator beam line (BL2) at SPring-8 Angstrom compact free-electron laser (SACLA), pulse-by-pulse switching between two beam lines was tested using kicker and dc twin-septum magnets. To maintain a compact size, all undulator beam lines at SACLA are designed to be placed within the same undulator hall located downstream of the accelerator. In order to ensure broad tunability of the laser wavelength, the electron bunches are accelerated to different beam energies optimized for the wavelengths of each beam line. In the demonstration, the 30 Hz electron beam was alternately deflected to two beam lines and simultaneous lasing was achieved with 15 Hz at each beam line. Since the electron beam was deflected twice by 3° in a dogleg to BL2, the coherent synchrotron radiation (CSR) effects became non-negligible. Currently in a wavelength range of 4-10 keV, a laser pulse energy of 100 - 150 μ J can be obtained with a reduced peak current of around 1 kA by alleviating the CSR effects. This paper reports the results and operational issues related to the multi-beam-line operation of SACLA.

  19. Target and orbit feedback simulations of a muSR beam line at BNL

    Energy Technology Data Exchange (ETDEWEB)

    MacKay, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States); Fischer, W. [Brookhaven National Lab. (BNL), Upton, NY (United States); Pile, P. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-07-28

    Well-polarized positive surface muons are a tool to measure the magnetic properties of materials since the precession rate of the spin can be determined from the observation of the positron directions when the muons decay. For a dc beam an ideal µSR flux for surface µ+ should be about 40 kHz/mm2. In this report we show how this flux could be achieved in a beam line using the AGS complex at BNL for a source of protons. We also determined that an orbit feedback system with a pair of thin silicon position monitors and kickers would miss the desired flux by at least an order of magnitude, even with perfect time resolution and no multiple scattering.

  20. The mechanical design of a bunched beam stochastic cooling tank for the FNAL Tevatron

    International Nuclear Information System (INIS)

    The stringent alignment required for successful bunched beam stochastic cooling in FNAL's Tevatron necessitates the design and manufacture of a complex vacuum compatible mechanical alignment system. The design presented uses remote motion control to provide a positioning system with four degrees of freedom for placing two symmetric pickup loop arrays about the proton beam and with two degrees of freedom for aligning the arrays relative to each other. The system provides a 7.62 cm aperture between arrays during injection and a 1.90 cm aperture during operation while maintaining alignment between arrays within 50 μm. The system also allows precise remote longitudinal adjustment between pickup arrays with .002 μm resolution via a piezoelectric crystal inchworm motor in vacuum. Discussion includes the manufacture and installation of four complete pickup and kicker systems in the FNAL, Tevatron

  1. A wide band slot-coupled beam sensing electrode for the Advanced Light Source (ALS)

    International Nuclear Information System (INIS)

    Stripline electrodes (traveling wave electrodes, directional couplers) are commonly used in particle accelerators as beam pickups and kickers. The longitudinally symmetric stripline has a constant beam coupling impedance as a function of length and has a characteristic magnitude sin(x) amplitude response in the frequency domain. An exponentially tapered stripline provides nearly constant coupling impedance vs. frequency and yields superior frequency-domain performance. In practice it is difficult to construct either of these devices for broad-band performance because of the transition from coaxial to stripline geometry. The authors report on the construction of an exponentially-tapered, slot-coupled 'stripline' which was relatively easy to construct and has the desired frequency response

  2. The 12 kV, 50 kA Pulse Generator for the SPS MKDH Horizontal Beam Dump Kicker System,equipped with Semiconductor Switches

    CERN Document Server

    Bonthond, J; Faure, P; Vossenberg, Eugène B; CERN. Geneva. SPS and LHC Division

    2001-01-01

    The high current pulses for the MKDH magnets are generated with capacitor discharge type generators which, combined with a resistive free-wheel diode circuit, deliver a critically damped half-sine current with a rise-time of 25 ms. Each generator consists of two 25 kA units, connected in parallel to a magnet via low inductance transmission lines. They are equipped with a stack of four Fast High Current Thyristors, together with snubber capacitors, a voltage divider and a specially designed trigger transformer.

  3. Cyclotrons for high-intensity beams

    CERN Document Server

    Seidel, Mike

    2013-01-01

    This paper reviews the important physical and technological aspects of cyclotrons for the acceleration of high-intensity beams. Special emphasis is given to the discussion of beam loss mechanisms and extraction schemes.

  4. RESONANT EXTRACTION PARAMETERS FOR THE AGS BOOSTER

    International Nuclear Information System (INIS)

    Brookhaven's AGS Booster is the injector for the AGS. It is being modified to send resonant extracted heavy ions to a new beam line, the Booster Applications Facility (BAF). The design of the resonant extraction system for BAF was described in [1]. This note will give a more detailed description of the system and describe the predicted resonant beam time structure. We will describe tune space manipulations necessary to extract the resonant beam at the maximum Booster rigidity, schemes for performing resonant extraction, and describe the modifications required to perform bunched beam extraction to the BAF facility

  5. Nonlinear beam-beam resonances

    International Nuclear Information System (INIS)

    Head-on collisions of bunched beams are considered, assuming the two colliding beams have opposite charges. A few experimental observations are described. The single resonance analysis is developed that is applicable to the strong-weak case of the beam-beam interaction. In this case, the strong beam is unperturbed by the beam-beam interaction; motions of the weak beam particles are then analyzed in the presence of the nonlinear electromagnetic force produced by the strong beam at the collision points. The coherent motions of the two coupled strong beams are shown to exhibit distinct nonlinear resonance behavior. 16 refs., 22 figs

  6. The NSCL electron beam ion trap for the reacceleration of rare isotopes coming to life: First extraction tests with a high-current electron gun

    International Nuclear Information System (INIS)

    NSCL is currently constructing the ReA3 reaccelerator, which will accelerate rare isotopes obtained from gas stopping of fast-fragment beams to energies of up to 3 MeV/u for uranium and higher for lighter ions. A high-current charge breeder, based on an electron beam ion trap (EBIT), has been chosen as the first step in the acceleration process, as it has the potential to efficiently produce highly charged ions in a single charge state. These ions are fed into a compact linear accelerator consisting of a radio frequency quadrupole structure and superconducting cavities. The NSCL EBIT has been fully designed with most of the parts constructed. The design concept of the EBIT and results from initial commissioning tests of the electron gun and collector with a temporary 0.4 T magnet are presented.

  7. Experimental evaluation of the radiological condition of HRVUV beam line of Indus-1 SRS at RRCAT

    International Nuclear Information System (INIS)

    Indus Accelerator Complex comprises of two Synchrotron Radiation Sources (SRS) namely Indus-1 and Indus-2 with maximum electron beam energy being 450 MeV and 2.5 GeV respectively. Presently there are 5 operational beam lines in Indus-1 and High Resolution Vacuum Ultra Violet (HRVUV) beam line is one among them. This beam line is especially significant from radiation safety point of view due to its position. HRVUV beam line area gets significant radiation field due to beam losses in Indus-1 injection septum, Transport lines 2 and 3 (TL2/TL3) and losses in TL3 in TL3 Tunnel. Due to this reason, entry in HRVUV beam line area was prohibited during various modes of machine operation. So an attempt was made to study the dose rates in this beam line area during various modes of machine operations including worst case scenarios. Subsequent to the study, shielding augmentation/modification to reduce the radiation levels in this area was carried out. (a) A sliding shield door of lead bricks was put at MS Grill Door to stop radiation streaming from TL3 Tunnel side. (b) Shielding augmentation was done at TL2 near SIP 5, (c) at TL3 beam shutter and (d) TL3 Beam Profile Monitor-1 (BPM1). (e) Beam physicist succeeded in reducing beam losses at TL2 by changing kicker delay timings by 9 nano seconds. All these efforts have resulted in significant reduction in radiation field in HRVUV beam line area. Based on the study of radiation levels and the subsequent shielding augmentation, this area is now made accessible during Indus-1 storage as well as during Indus-2 Injection with entry restrictions applicable based on prevailing radiological conditions. This paper presents the study of radiation levels in HRVUV beam line area and the corrective actions taken on the basis of the study. (author)

  8. Theoretical analysis of some problems in the measurement of beam divergence angle for EAST neutral beam injector

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Beam angular divergence is one of the indicators to evaluate the beam quality. Operating parameters of the beam extraction system could be adjusted to gain better beam quality following the measurement results, which will be helpful not only to study the transmission characteristics of the beam and the power distribution on the heat load components, but also to understand the real-time working condition of the ion source and beam extraction system. This study includes: (1) the theoretical analysis of beam extraction pulse duration for measurement of beam angular divergence; (2) the theoretical analysis of beam intensity distribution during beam transmission for Experimental Advanced Superconducting Tokomak (EAST) neutral beam injector. Those theoretical analyses could point the way to the measurement of beam divergence angle for EAST neutral beam injector.

  9. Evaluation of the radioprotective effect of Carissa carandas Linn. fruit extract in cultured human peripheral blood lymphocytes exposed to electron beam radiation by Single Cell Gel Electrophoresis (Comet Assay)

    International Nuclear Information System (INIS)

    Radiation is a well-known inducer of free radicals and compounds that can scavenge free radicals may reduce radiation-induced DNA damage. Carissa carandas commonly known as Karanda belongs to family Apocynaceae. Traditionally, whole plant and its parts were used in the treatment of various ailments. The aim of the present study was to assess the radioprotective effect of ethanolic extract of Carissa carandas fruit (ECF) in cultured human peripheral blood lymphocytes (HPBLs) by comet assay. The optimum protective dose of the extract was selected by treating HPBLs with 50 and 100 μg/ml ECF after exposure to 2 Gy electron beam radiation and then evaluating the frequency of DNA damage in HPBLs using Single cell gel electrophoresis (Comet Assay). To understand the mechanism of action of ECF separate experiments were conducted to evaluate the free radical scavenging of DPPH, and Fe3+ in vitro. ECF was found to inhibit free radicals in a dose dependent manner up to a dose of 1000 μg/ml for the majority of radicals as observed by the in vitro free radical scavenging assays. The irradiation of HPBLs with 2 Gy dose of electron beam radiation caused an increase in the frequency of DNA damage while treatment of HPBLs with different concentrations of ECF reduced the frequency of DNA damage significantly with the greatest reduction being observed for 100 μg/ml when compared with the irradiated control. Our study demonstrates the potential of ECF as an effective agent against radiation induced DNA damage. (author)

  10. Analysis of methods for obtaining of a uniform particle distribution on a target on its irradiation by a beam of the krypton ions extracted from the implantator IC-100

    CERN Document Server

    Gikal, B N; Kazarinov, N

    2002-01-01

    Some methods of the target uniform irradiation by heavy ions have been analyzed. As a result the scanning system for the sup 8 sup 4 Kr sup 1 sup 5 sup + ion beam extracted from the cyclotron IC-100 has been chosen and worked up. It consists of two deflecting yokes creating horizontal and vertical magnetic fields. The yokes are supplied by generators of saw-tooth current having the definitely fixed frequencies. When both generators work synchronously the centre of mass of the ion beam 'draws' a pattern on the target. The dimensions of the pattern cells are determined by the ratio of these frequencies. The correlation between the generator frequencies when heterogeneity of the particle density distribution does not exceed the required value of +- 5% is obtained. It has been shown that for the moving target the chosen scanning scheme allows one to obtain its uniform density distribution. For the slow target velocities (20-50 cm/s) this scheme also allows one to compensate the collapse in the particle density di...

  11. Beam catcher/dump

    International Nuclear Information System (INIS)

    A simple, low cost aperture limiting device with an absorber block has been developed and installed in the AGS ring at Brookhaven National Laboratory. The device intercepts injection tails, transition losses, and the inward spiraling beam of an aborted accelerations or extraction cycle. The resultant consolidation of losses at one point reduces activation of components around the ring and radiation exposure to personnel

  12. Bessel Beams

    OpenAIRE

    McDonald, Kirk T

    2000-01-01

    Scalar Bessel beams are derived both via the wave equation and via diffraction theory. While such beams have a group velocity that exceeds the speed of light, this is a manifestation of the "scissors paradox" of special relativty. The signal velocity of a modulated Bessel beam is less than the speed of light. Forms of Bessel beams that satisfy Maxwell's equations are also given.

  13. First Operational Experience with the LHC Beam Dump Trigger Synchronisation Unit

    CERN Document Server

    Antoine, A; Magnin, N; Juteau, P; Voumard, N

    2011-01-01

    Two LHC Beam Dumping Systems (LBDS) remove the counter-rotating beams safely from the collider during setting up of the accelerator, at the end of a physics run and in case of emergencies. Dump requests can come from 3 different sources: the machine protection system in emergency cases, the machine timing system for scheduled dumps or the LBDS itself in case of internal failures. These dump requests are synchronized with the 3 μs beam abort gap in a fail-safe redundant Trigger Synchronization Unit (TSU) based on a Digital Phase Locked Loop (DPLL), locked onto the LHC beam revolution frequency with a maximum phase error of 40 ns. The synchronized trigger pulses coming out of the TSU are then distributed to the high voltage generators of the beam dump kickers through a redundant fault-tolerant trigger distribution system. This paper describes the operational experience gained with the TSU since its commissioning with beam in 2009, and highlights the improvements, which have been implemented f...

  14. First operational experience with the LHC beam dump trigger synchronization unit

    International Nuclear Information System (INIS)

    Two LHC Beam Dumping Systems (LBDS) remove the counter-rotating beams safely from the collider during setting up of the accelerator, at the end of a physics run and in case of emergencies. Dump requests can come from 3 different sources: the machine protection system in emergency cases, the machine timing system for scheduled dumps or the LBDS itself in case of internal failures. These dump requests are synchronized with the 3 μs beam abort gap in a fail-safe redundant Trigger Synchronization Unit (TSU) based on a Digital Phase Locked Loop (DPLL), locked onto the LHC beam revolution frequency with a maximum phase error of 40 ns. The synchronized trigger pulses coming out of the TSU are then distributed to the high voltage generators of the beam dump kickers through a redundant fault-tolerant trigger distribution system. This paper describes the operational experience gained with the TSU since its commissioning with beam in 2009, and highlights the improvements, which have been implemented for a safer operation. This includes an increase of the diagnosis and monitoring functionalities and a more automated validation of the hardware and embedded firmware before deploying or executing a post-operational analysis of the TSU performance, after each dump action. In the light of this first experience the outcome of the external review performed in 2010 is presented. The lessons learnt on the project life cycle for the design of mission critical electronic modules are discussed. (authors)

  15. ATF neutral beam injection: optimization of beam alignment and aperturing

    International Nuclear Information System (INIS)

    The application of the existing Impurity Study Experiment (ISX-B) neutral beam injectors for the Advanced Toroidal Facility (ATF) is studied. It is determined that with the practical considerations of beam aperturing, ATF vacuum vessel complexity, and realistic beam modeling, the power absorbed by the plasma will be approximately 57% of the extracted neutral beam power, which corresponds to an injected power of about 1.5 MW. By reducing the beam divergence to a 10 Gaussian distribution, the absorbed power could be increased to 93%. The power delivered to the plasma is found to be a strong function of the beam divergence but only a weak function of the beam focal length. Shinethrough can be a serious problem if very low density startups are necessary. Preliminary calculations indicate that there will be no excessive fast-ion losses. 12 refs., 17 figs., 1 tab

  16. SU-E-J-150: Four-Dimensional Cone-Beam CT Algorithm by Extraction of Physical and Motion Parameter of Mobile Targets Retrospective to Image Reconstruction with Motion Modeling

    International Nuclear Information System (INIS)

    Purpose: To develop 4D-cone-beam CT (CBCT) algorithm by motion modeling that extracts actual length, CT numbers level and motion amplitude of a mobile target retrospective to image reconstruction by motion modeling. Methods: The algorithm used three measurable parameters: apparent length and blurred CT number distribution of a mobile target obtained from CBCT images to determine actual length, CT-number value of the stationary target, and motion amplitude. The predictions of this algorithm were tested with mobile targets that with different well-known sizes made from tissue-equivalent gel which was inserted into a thorax phantom. The phantom moved sinusoidally in one-direction to simulate respiratory motion using eight amplitudes ranging 0–20mm. Results: Using this 4D-CBCT algorithm, three unknown parameters were extracted that include: length of the target, CT number level, speed or motion amplitude for the mobile targets retrospective to image reconstruction. The motion algorithms solved for the three unknown parameters using measurable apparent length, CT number level and gradient for a well-defined mobile target obtained from CBCT images. The motion model agreed with measured apparent lengths which were dependent on the actual target length and motion amplitude. The gradient of the CT number distribution of the mobile target is dependent on the stationary CT number level, actual target length and motion amplitude. Motion frequency and phase did not affect the elongation and CT number distribution of the mobile target and could not be determined. Conclusion: A 4D-CBCT motion algorithm was developed to extract three parameters that include actual length, CT number level and motion amplitude or speed of mobile targets directly from reconstructed CBCT images without prior knowledge of the stationary target parameters. This algorithm provides alternative to 4D-CBCT without requirement to motion tracking and sorting of the images into different breathing phases

  17. Beam Transfer and Machine Protection

    CERN Document Server

    Kain, V

    2016-01-01

    Beam transfer, such as injection into or extraction from an accelerator, is one of the most critical moments in terms of machine protection in a high-intensity machine. Special equipment is used and machine protection aspects have to be taken into account in the design of the beam transfer concepts. A brief introduction of the principles of beam transfer and the equipment involved will be given in this lecture. The main concepts of machine protection for injection and extraction will be presented, with examples from the CERN SPS and LHC.

  18. Electron beam linac simulations, 1985

    International Nuclear Information System (INIS)

    The results of particle simulation studies of electron beam problems for the year 1985 are summarized. Although the main subjects this year were mostly the same as in previous years, namely foilless diodes, accelerating gaps, and beam extraction, a major new element this year was the addition of IFR (ion-focused-regime) channels to the various components of a linac beam line. Of particular interest may be the new results obtained for IFR autoacceleration gaps (relevant to MIMI), and the studies of extraction from a guide magnetic field onto an IFR propagation channel (relevant to RADLAC II). 49 figs., 20 refs

  19. Electron Beam Ion Sources

    CERN Document Server

    Zschornacka, G; Thorn, A

    2013-01-01

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviolet, visible light) from highly charged ions. This chapter gives an overview of EBIS physics, the principle of operation, and the known technical solutions. Using examples, the performance of EBISs as well as their applications in various fields of basic research, technology and medicine are discussed.

  20. Injection line of 1+ ion beam for electron beam ion-charge breeding source and related beam elements

    International Nuclear Information System (INIS)

    Main purpose of the electron beam ion-charge breeding source (EBIBS) is to produce highly pure and highly charged ion beam from single charge ion of stable or radioactive species. It can accept low emittance ion beam from either online or offline ECR ion sources (ECRIS). The emittance of the extracted beam is low at lower RF frequencies and magnetic field of the ECRIS. The beam at the position of extraction is approximately reproduced at the entrance of the electron collector of the EBIBS. The beam moves forward under the influence of the negative potential deep of the electron beam and enters the ionization region in solenoid field of the EBIBS. The injection line starts at the extraction region of the ECRIS. The assumed parameters of the extracted beam of 20 keV energy and 0.0732 GeV/c momentum for injection are 10 mm diameter and 30 mrad beam divergence cone. As mass number of the ions decreases the energy decreases for constant momentum of the ion beam. The value of the momentum or the beam rigidity is judiciously chosen to encompass the most of the isotopes of various elements. The beam is focused by a quadrupole doublet and passes the beam through a 90° bending magnet. The beam is analyzed also by the dipole magnet to remove the contaminants and the selected ion beam is focused by a quadrupole doublet magnet to pass through an electrostatic 90° bending elements. The beam approaches the opening of 16 mm diameter of the electron collector. A round beam of 12 mm diameter is achieved here with the help of a quadrupole triplet through point-to-point imaging from start to the end. The transport matrices for the electrostatic bending elements were calculated and incorporated into the TRANSPORT code. (author)

  1. Capture, Electron-Cooling and Compression of Antiprotons in a Large Penning-Trap for Physics Experiments with an Ultra-Low Energy Extracted Antiproton Beam

    CERN Multimedia

    2002-01-01

    % PS200 \\\\ \\\\The availability of ultra-low energy antiprotons is a crucial ingredient for the execution of the gravity measurements PS200. We have developed a method to provide such low energy antiprotons based on a large Penning trap (the PS200 catching trap). This system can accept a fast-extracted pulse from LEAR, reduce the energy of the antiprotons in the pulse from 5.9~MeV to several tens of kilovolts using a degrading foil, and then capture the antiprotons in a large Penning trap. These antiprotons are cooled by electrons previously admitted to the trap and are collected in a small region at the center of the trap. We have demonstrated our capability to capture up to 1~million antiprotons from LEAR in a single shot, electron cool these antiprotons, and transfer up to 95\\% of them into the inner, harmonic region. A storage time in excess of 1 hour was observed. These results have been obtained with the cryogenic trap vacuum coupled to a room temperature vacuum at about l0$ ^- ^{1} ^0 $ Torr, which is an...

  2. Slow extraction system of the KEK-PS

    International Nuclear Information System (INIS)

    Half-integer resonance extraction at 2νH=15 has been utilized for the KEK 12-GeV Proton Synchrotron (KEK-PS). Performance of the slow extraction has been progressing recently. A slow beam extraction system was constructed for the newly build North Counter Hall. For the old East Counter Hall, the power rating of the slow extraction instruments was improved in connection with an elongation of the flat-top. The quality of the extracted beam (extraction efficiency, beam emittances and spill structure) has been systematically measured and improved by concentrated efforts. Further, a new variation of the extraction modes (deuteron beam extraction and lower energy beam extraction) has been achieved in order to contribute to the various fields of physical experiments. This report gives up-to-date descriptions of the slow extraction system of the KEK-PS. (author)

  3. SU-E-J-252: A Motion Algorithm to Extract Physical and Motion Parameters of a Mobile Target in Cone-Beam Computed Tomographic Imaging Retrospective to Image Reconstruction

    International Nuclear Information System (INIS)

    Purpose: A motion algorithm was developed to extract actual length, CT-numbers and motion amplitude of a mobile target imaged with cone-beam-CT (CBCT) retrospective to image-reconstruction. Methods: The motion model considered a mobile target moving with a sinusoidal motion and employed three measurable parameters: apparent length, CT number level and gradient of a mobile target obtained from CBCT images to extract information about the actual length and CT number value of the stationary target and motion amplitude. The algorithm was verified experimentally with a mobile phantom setup that has three targets with different sizes manufactured from homogenous tissue-equivalent gel material embedded into a thorax phantom. The phantom moved sinusoidal in one-direction using eight amplitudes (0–20mm) and a frequency of 15-cycles-per-minute. The model required imaging parameters such as slice thickness, imaging time. Results: This motion algorithm extracted three unknown parameters: length of the target, CT-number-level, motion amplitude for a mobile target retrospective to CBCT image reconstruction. The algorithm relates three unknown parameters to measurable apparent length, CT-number-level and gradient for well-defined mobile targets obtained from CBCT images. The motion model agreed with measured apparent lengths which were dependent on actual length of the target and motion amplitude. The cumulative CT-number for a mobile target was dependent on CT-number-level of the stationary target and motion amplitude. The gradient of the CT-distribution of mobile target is dependent on the stationary CT-number-level, actual target length along the direction of motion, and motion amplitude. Motion frequency and phase did not affect the elongation and CT-number distributions of mobile targets when imaging time included several motion cycles. Conclusion: The motion algorithm developed in this study has potential applications in diagnostic CT imaging and radiotherapy to extract

  4. Feedback control and beam diagnostic algorithms for a multiprocessor DSP system

    International Nuclear Information System (INIS)

    The multibunch longitudinal feedback system developed for use by PEP-II, ALS, and DAΦNE uses a parallel array of digital signal processors (DSPs) to calculate the feedback signals from measurements of beam motion. The system is designed with general-purpose programmable elements which allow many feedback operating modes as well as system diagnostics, calibrations, and accelerator measurements. The overall signal processing architecture of the system is illustrated. The real-time DSP algorithms and off-line postprocessing tools are presented. The problems in managing 320k samples of data collected in one beam transient measurement are discussed and our solutions are presented. Example software structures are presented showing the beam feedback process, techniques for modal analysis of beam motion (used to quantify growth and damping rates of instabilities), and diagnostic functions (such as timing adjustment of beam pick-up and kicker components). These operating techniques are illustrated with example results obtained from the system installed at the Advanced Light Source at LBL. copyright 1997 American Institute of Physics

  5. A beam source model for scanned proton beams

    International Nuclear Information System (INIS)

    A beam source model, i.e. a model for the initial phase space of the beam, for scanned proton beams has been developed. The beam source model is based on parameterized particle sources with characteristics found by fitting towards measured data per individual beam line. A specific aim for this beam source model is to make it applicable to the majority of the various proton beam systems currently available or under development, with the overall purpose to drive dose calculations in proton beam treatment planning. The proton beam phase space is characterized by an energy spectrum, radial and angular distributions and deflections for the non-modulated elementary pencil beam. The beam propagation through the scanning magnets is modelled by applying experimentally determined focal points for each scanning dimension. The radial and angular distribution parameters are deduced from measured two-dimensional fluence distributions of the elementary beam in air. The energy spectrum is extracted from a depth dose distribution for a fixed broad beam scan pattern measured in water. The impact of a multi-slab range shifter for energy modulation is calculated with an own Monte Carlo code taking multiple scattering, energy loss and straggling, non-elastic and elastic nuclear interactions in the slab assembly into account. Measurements for characterization and verification have been performed with the scanning proton beam system at The Svedberg Laboratory in Uppsala. Both in-air fluence patterns and dose points located in a water phantom were used. For verification, dose-in-water was calculated with the Monte Carlo code GEANT 3.21 instead of using a clinical dose engine with approximations of its own. For a set of four individual pencil beams, both with the full energy and range shifted, 96.5% (99.8%) of the tested dose points satisfied the 1%/1 mm (2%/2 mm) gamma criterion

  6. Beam test of wire scanner beam size monitor

    International Nuclear Information System (INIS)

    A beam size monitor for emittance measurement is required to have around 10μm resolution for injector linac, and to have a few tenth μm resolution for an extracted beam from a damping ring in Accelerator Test Facility (ATF). A wire scanner is a one of the candidate of a beam size monitor with a high resolution. The design and development study of the wire scanning stage has been done. The beam test using Tohoku 300MeV Linac was done and the emittance was measured by this wire scanner. A detection of beam size signal was done by a scintillator gamma detector placed at downstream of the wire stage. All of the measurements are taken by the computer. The beam test results are described. (author)

  7. Beam - cavity interaction beam loading

    International Nuclear Information System (INIS)

    The interaction of a beam with a cavity and a generator in cyclic accelerators or storage rings is investigated. Application of Maxwell's equations together with the nonuniform boundary condition allows one to get an equivalent circuit for a beam-loaded cavity. The general equation for beam loading is obtained on the basis of the equivalent circuit, and the beam admittance is calculated. Formulas for power consumption by a beam-loaded cavity are derived, and the optimal tuning and coupling factor are analyzed. (author)

  8. Computer simulation of high current uranium beams for the injection beam line of the UNILAC

    International Nuclear Information System (INIS)

    In an attempt to generate an ion beam with high current and high brightness for the design ion, the computer code KOBRA3-INP has been used to evaluate the extraction system, the DC post-acceleration system as well as the quadrupole transport beam line, and to study the behavior of the ion beam in the combined system. (orig.)

  9. Beam catcher/dump

    International Nuclear Information System (INIS)

    A simple, low cost aperture limiting device with an absorber block has been developed and installed in the AGS ring at Brookhaven National Laboratory. The device intercepts injection tails, transition losses, and the inward spiraling beam of an aborted acceleration or extraction cycle. The resultant consolidation of losses at one point reduces activation of components around the ring and radiation exposure to personnel. 3 refs., 6 figs

  10. Suppression of stored beam oscillation at injection in the SPring-8 storage ring

    International Nuclear Information System (INIS)

    In the SPring-8 storage ring, when the injection bump orbit is not closed perfectly at the beam injection, the horizontal stored beam oscillation of the amplitude more than 0.5 mm (r.m.s.) is excited. Now, the averaged oscillation amplitude has successfully been suppressed to the level of less than 0.15 mm (r.m.s.) by applying a counter kick to the residual oscillation with a pulse width of 500 ns. To confirm the suppression effect, we observed the turn-by-turn photon beam profile at the diagnostics beamline with the insertion device. The light axis oscillation was significantly suppressed down to less than 4 μrad from more than 30μrad by applying a counter kick at 3rd turn after injection. Without the kicker correction, it took about 80 turns to reduce the oscillation, which was determined by the damping time with the bunch by bunch feedback system. In the SPring-8 user operation, in addition to the effect of providing stable photon beam, we succeeded in not only shortening the effective damping time but also filling a single high current bunch up to 5 mA to any bucket address. (author)

  11. Frozen Beams

    CERN Document Server

    Okamoto, Hiromi

    2005-01-01

    In general, the temperature of a charged particle beam traveling in an accelerator is very high. Seen from the rest frame of the beam, individual particles randomly oscillate about the reference orbit at high speed. This internal kinetic energy can, however, be removed by introducing dissipative interactions into the system. As a dissipative process advances, the beam becomes denser in phase space or, in other words, the emittance is more diminished. Ideally, it is possible to reach a "zero-emittance" state where the beam is Coulomb crystallized. The space-charge repulsion of a crystalline beam just balances the external restoring force provided by artificial electromagnetic elements. In this talk, general discussion is made of coasting and bunched crystalline beams circulating in a storage ring. Results of molecular dynamics simulations are presented to demonstrate the dynamic nature of various crystalline states. A possible method to approach such an ultimate state of matter is also discussed.

  12. Beam loading

    CERN Document Server

    Gamp, Alexander

    2013-01-01

    We begin by giving a description of the radio-frequency generator-cavity-beam coupled system in terms of basic quantities. Taking beam loading and cavity detuning into account, expressions for the cavity impedance as seen by the generator and as seen by the beam are derived. Subsequently methods of beam-loading compensation by cavity detuning, radio-frequency feedback and feedforward are described. Examples of digital radio-frequency phase and amplitude control for the special case of superconducting cavities are also given. Finally, a dedicated phase loop for damping synchrotron oscillations is discussed.

  13. Beam Instabilities

    CERN Document Server

    Rumolo, G

    2014-01-01

    When a beam propagates in an accelerator, it interacts with both the external fields and the self-generated electromagnetic fields. If the latter are strong enough, the interplay between them and a perturbation in the beam distribution function can lead to an enhancement of the initial perturbation, resulting in what we call a beam instability. This unstable motion can be controlled with a feedback system, if available, or it grows, causing beam degradation and loss. Beam instabilities in particle accelerators have been studied and analysed in detail since the late 1950s. The subject owes its relevance to the fact that the onset of instabilities usually determines the performance of an accelerator. Understanding and suppressing the underlying sources and mechanisms is therefore the key to overcoming intensity limitations, thereby pushing forward the performance reach of a machine.

  14. Injection and extraction for cyclotrons

    CERN Document Server

    Kleeven, W

    2006-01-01

    The main design goals for beam injection are explained and special problems related to a central region with internal ion source are considered. The principle of a PIG source is addressed. The issue of vertical focusing in the cyclotron centre is briefly discussed. Several examples of numerical simulations are given. Different ways of (axial) injection are briefly outlined. A proposal for a magnetostatic axial inflector is given. Different solutions for beam extraction are treated. These include the internal target, extraction by stripping, resonant extraction using a deflector and self-extraction. The different ways of creating a turn-separation are explained. The purpose of different types of extraction devices such as harmonic coils, deflectors and gradient corrector channels are outlined. Several illustrations are given in the form of photographs and drawings.

  15. A computer code for computing the beam profiles in the NBI beam line 'BEMPROF'

    International Nuclear Information System (INIS)

    A computer code was developed which can compute the beam profiles and the percentage heat loadings on the various components in the NBI beam line such as the beam target, the beam limiters and the calorimeter. The geometrical injection efficiency of NBI and the heat input pattern on the counter surface of the injection port of the torus can also be computed. The major feature of this code is that the effects of the beamlet intensity distribution, the beamlet deflection, the beam screening by the upstream limiters and also the plasma density distribution and the divergence angle distribution over the beam extraction area can be taken into account. (author)

  16. CERN Multimedia

    1975-01-01

    Sometimes in English sometimes in French. Synthesis film of series of films about SPS produced by CERN. De Raad, beam transfer. Surveying for placement of SPS. Gervaise. La Robbins. Levy Mandel, construction of tunnel. Surveying for installation of elements of the accelerator. Billings, magnet system, classes of errors, properties of the steel used in magnets, bending strength. Precision measurements. Magnet assembly. Discussion kicker magnets. Beam extraction system. Beam transfer and splitting system. Beam dump.

  17. A Study of the Beam Physics in the CLIC Drive Beam Decelerator

    CERN Document Server

    Adli, Erik; Stapnes, Steinar

    2009-01-01

    CLIC is a study for a Multi-TeV e+e- linear collider, in which the rf power for the main linacs is extracted from 100 ampere electron drive beams, by the use of specially designed power extraction structures. Up to 90% of the beam energy is extracted from the drive beams along one kilometer long decelerator sectors, rendering the beam transport challenging. We have identified two major challenges for robust beam transport: the significant transverse wakes in the power extraction structures, and the large energy spread induced by the power extraction process. By beam dynamics studies we have qualified power extraction structure designs, leading to the present CLIC baseline structure in which the transverse wakes are sufficiently mitigated. We have further shown that the beam energy spread induced by the deceleration implies that standard 1-to-1 correction might not ensure satisfactory drive beam transport. As alternative, we propose a decelerator orbit correction scheme based on dispersion-free steering and ex...

  18. Preliminary Measurement of Beam Power Transmission in KSTAR Neutral Beam Test-Stand

    International Nuclear Information System (INIS)

    A neutral beam test-stand (NBTS) was constructed to develop 300-sec deuterium beam extraction of 120 kV/65 A as an auxiliary heating system of KSTAR. The ion source is composed of a plasma generator and a tetrode accelerator. The beamline components include an optical multi-channel analyzer (OMA) duct, a neutralizer, a bending magnet (BM), an ion dump, a calorimeter, and a cryo-sorption pump system. Beam deposition along the NBTS has been measured by water flow calorimetry (WFC) and 96 % of the extracted beam power (Vacc·Iacc) was counted for a beam of 97 kV/22.2 A. Maximum power transmission efficiency, which is the ratio of transmitted power on the calorimeter to the extracted beam power, was 0.77 with an optimum perveance of 1.1 microperv

  19. Large area ion and plasma beam sources

    International Nuclear Information System (INIS)

    In the past a number of ion beam sources utilizing different methods for plasma excitation have been developed. Nevertheless, a widespread use in industrial applications has not happened, since the sources were often not able to fulfill specific demands like: broad homogeneous ion beams, compatibility with reactive gases, low ion energies at high ion current densities or electrical neutrality of the beam. Our contribution wants to demonstrate technical capabilities of rf ion and plasma beam sources, which can overcome the above mentioned disadvantages. The physical principles and features of respective sources are presented. We report on effective low pressure plasma excitation by electron cyclotron wave resonance (ECWR) for the generation of dense homogeneous plasmas and the rf plasma beam extraction method for the generation of broad low energy plasma beams. Some applications like direct plasma beam deposition of a-C:H and ion beam assisted deposition of Al and Cu with tailored thin film properties are discussed. (orig.)

  20. The extractant

    International Nuclear Information System (INIS)

    The extractant for extraction and re-extraction of heavy metal ions has been worked out. The extractant consists of ferromagnetic particles suspended in liquid and covered by unsaturated fatty acids. The liquid, unsoluble in other liquids taken part in the process, contains also an organic derivative of phosphoric acid as a complexing agent

  1. Optimization of crystal extraction experiment

    OpenAIRE

    Biryukov, Valery

    2001-01-01

    Using a computer model for the crystal extraction, we investigate the bent-crystal parameters optimal for the extraction experiment. The optimal crystal curvature is found to be near 1 GeV/cm (for pv/R), i.e. a factor of 2--3 higher than for the crystal application in beam lines. An influence of the accelerator optics on extraction is discussed. A possibility of using the high-Z crystals for extraction is considered. The simulations for the ongoing experiments at the CERN-SPS and the Fermilab...

  2. Evaluation of Rosenbaum's proposal for locally increasing the effective vertical emittance of the APS beam.

    CERN Document Server

    Emery, L; Sereno, N S

    2003-01-01

    At the APS Retreat in May 2002, G. Rosenbaum proposed a method for increasing the effective vertical emittance of the APS beam. His proposal, illustrated in Figure 1, is to use a rapidly-modulated four-magnet vertical position bump in a single straight section. The proposed modulation frequency is a 10-kHz triangle wave, with a kick angle of 0.65 mrad. There are several aspects of this proposal that may be problematical: (1) The high modulation frequency will require the use of a ceramic chamber with a thin conductive coating, similar to what is used for the injection kicker magnets. This is not necessarily a problem, but the following aspects need to be examined: (a) The chamber coating needs to be specified correctly to ensure that the beam motion reflects the desired triangle-wave pattern. (b) The effect of the eddy currents in the chamber on the multipole content of the magnetic field needs to be computed, to ensure that the system does not have undesirable effects on the beam. (2) The magnets and their c...

  3. Molecular beams

    International Nuclear Information System (INIS)

    This book is a timeless and rather complete theoretical and experimental treatment of electric and magnetic resonance molecular-beam experiments for studying the radio frequency spectra of atoms and molecules. The theory of interactions of the nucleus with atomic and molecular fields is extensively presented. Measurements of atomic and nuclear magnetic moments, electric multipole moments, and atomic fine and hyperfine structure are detailed. Useful but somewhat outdated chapters on gas kinetics, molecular beam design, and experimental techniques are also included

  4. Ions beams. Theory and implementation

    International Nuclear Information System (INIS)

    After a presentation of the physical phenomena implied by ions beams (stopping power, defects creation), the implementation of ions beams is described (production, separation in terms of masses, experimental devices). Then, two use modes of ions beams are distinguished: analysis and synthesis. When the ion beam is destined to analysis, there are two possible experiments types. In the first case, the sample to be studied is the source of ions production and the analysis consists to separate in mass the ions extracted; this method is destructive. In the second case, the analysis results of the interaction between the light ions beam and a target: the sample. According to the nature of the analysis, different types of detectors can be used to quantify the energy of the particles diffused by the sample (fluorescence, back-scattering of particles). When ions beams are used as tools of controlled alterations of samples, several parameters (energy, flux, dose, nature of the beam, target temperature) are adjustable following to the searched objective (defects creation, ordering, synthesis of new phases or surfaces alteration). The typical experimental devices used for beams production (scheme of sources principle) and the environment of the sample are described in terms of the applications studied. (O.M.)

  5. Beam emittance and beam disruption

    International Nuclear Information System (INIS)

    Beam disruption during the collision of intense relativistic bunches has been studied by R. Hollebeek. In the case of oppositely charged bunches, focussing effects occur causing a decrease in the effective bunch cross section, and thereby an increase of luminosity by an enhancement factor H. The term disruption derives from the fact that the beam emittance changes markedly during the collision. 1 ref., 1 fig., 1 tab

  6. Streak Camera Studies of Vertical Synchro-Betatron-Coupled Electron Beam Motion in the APS Storage Ring

    CERN Document Server

    Yang Bing Xin; Guo, Weiming; Harkay, Katherine C; Sajaev, Vadim

    2005-01-01

    We present experimental studies of synchro-betatron-coupled electron beam motion in the Advanced Photon Source storage ring. We used a vertical kicker to start the beam motion. When the vertical chromaticity is nonzero, electrons with different initial synchrotron phases have slightly different betatron frequencies from the synchronous particle, resulting in a dramatic progression of bunch-shape distortion. Depending on the chromaticity and the time following the kick, images ranging from a simple vertical tilt in the bunch to more complicated twists and bends are seen with a visible light streak camera. Turn-by-turn beam position monitor data were taken as well. We found that the experimental observations are well described by the synchro-betatron-coupled equations of motion. We are investigating the potential of using the tilted bunch to generate picosecond x-ray pulses. Also note that the fast increase in vertical beam size after the kick is dominated by the internal synchro-betatron-coupled motion of the ...

  7. Tooth extraction

    Science.gov (United States)

    A tooth extraction is a procedure to remove a tooth from the gum socket. It is usually done by a general ... gum. If you need a more complex tooth extraction: You will be given sedation so you are ...

  8. Study of electron beam production by a plasma focus

    International Nuclear Information System (INIS)

    A preliminary investigation of the electron beam produced by a plasma focus device using a current charged transmission line is described. Electron beam currents as high as 10 kA were measured. Interaction of the extracted beam and the filling gas was studied using open shutter photography

  9. Experimental Program for the CLIC test facility 3 test beam line

    CERN Document Server

    Adli, E; Dobert, S; Olvegaard, M; Schulte, D; Syratchev, I; Lillestol, Reidar

    2010-01-01

    The CLIC Test Facility 3 Test Beam Line is the first prototype for the CLIC drive beam decelerator. Stable transport of the drive beam under deceleration is a mandatory component in the CLIC two-beam scheme. In the Test Beam Line more than 50% of the total energy will be extracted from a 150 MeV, 28 A electron drive beam, by the use of 16 power extraction and transfer structures. A number of experiments are foreseen to investigate the drive beam characteristics under deceleration in the Test Beam Line, including beam stability, beam blow up and the efficiency of the power extraction. General benchmarking of decelerator simulation and theory studies will also be performed. Specially designed instrumentation including precision BPMs, loss monitors and a time-resolved spectrometer dump will be used for the experiments. This paper describes the experimental program foreseen for the Test Beam Line, including the relevance of the results for the CLIC decelerator studies.

  10. ILC Extraction Line Simulations with TDR Parameters

    CERN Document Server

    Marin, Eduardo

    2014-01-01

    The goal of this study is to evaluate the impact of the latest ILC beam parameters at the Interaction Point (IP), as specified in the 2013 ILC Technical Design Report (TDR), on beam losses in the extraction line. The previous beam loss evaluation was based on the parameters specified in the 2007 ILC Reference Design Report (RDR). The results of this study are compared to the results obtained in the past for the ``nominal'' and the ``low power'' (low-P) parameter options of the RDR. The initial disrupted beam distribution at IP was generated using Guinea-Pig code, and the beam losses were obtained in tracking simulations using DIMAD. The study is performed for 500 GeV center-of-mass beam energy and the extraction line optics corresponding to the latest final focus optics with L* = 4.5 m, with and without detector solenoid.

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

    International Nuclear Information System (INIS)

    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 used in conjunction with a video camera. The visual representation of the beam structure is digitized enhanced through false-color coding, and displayed on a TV monitor for on-line viewing. The 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 measuring transverse emittance (or angular spread). This technique 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)

  12. Laser diagnostic for high current H- beams

    International Nuclear Information System (INIS)

    In the last 5 years, significant technology advances have been made in the performance, size, and cost of solid-state diode-pumped lasers. These developments enable the use of compact Q-switched Nd:YAG lasers as a beam diagnostic for high current H- beams. Because the threshold for photodetachment is only 0.75 eV, and the maximum detachment cross section is 4x10-17cm2 at 1.5 eV, A 50 mJ/pulse Q-switched Nd:YAG laser can neutralize a significant fraction of the beam in a single 10 ns wide pulse. The neutral beam maintains nearly identical parameters as the parent H- beam, including size, divergence, energy, energy spread, and phase spread. A dipole magnet can separate the neutral beam from the H- beam to allow diagnostics on the neutral beam without intercepting the high-current H- beam. Such a laser system can also be used to extract a low current proton beam, or to induce fluorescence in partially stripped heavy ion beams. Possible beamline diagnostic systems will be reviewed, and the neutral beam yields will be calculated. copyright 1998 American Institute of Physics

  13. Extraction process

    International Nuclear Information System (INIS)

    A process is described for extracting at least two desired constituents from a mineral, using a liquid reagent which produces the constituents, or compounds thereof, in separable form and independently extracting those constituents, or compounds. The process is especially valuable for the extraction of phosphoric acid and metal values from acidulated phosphate rock, the slurry being contacted with selective extractants for phosphoric acid and metal (e.g. uranium) values. In an example, uranium values are oxidized to uranyl form and extracted using an ion exchange resin. (U.K.)

  14. Beam dynamics with new booster dipoles

    International Nuclear Information System (INIS)

    New bending magnets are being designed for the booster synchrotron at RRCAT, Indore with the same effective length and field which will be installed in the existing ring with the same configuration of drifts and quadrupole magnets. Presently sector type dipoles are in use. It is easier to fabricate parallel edge (rectangular type) dipoles but the beam optics gets modified due to edges which provide additional focusing. The effect on tune point can be corrected using two quadrupole families. Studies indicate that the beam emittance is lower in the optics with rectangular type dipoles but the beam injection and extraction are more difficult. In this paper, the beam optics, beam emittance, injection and extraction with two configurations of the dipole magnets are compared. (author)

  15. A reflex electron beam discharge as a plasma source for electron beam generation

    International Nuclear Information System (INIS)

    A reflex electron beam glow discharge has been used as a plasma source for the generation of broad-area electron beams. An electron current of 120 A (12 A/cm/sup 2/) was extracted from the plasma in 10 μs pulses and accelerated to energies greater than 1 keV in the gap between two grids. The scaling of the scheme for the generation of multikiloamp high-energy beams is discussed

  16. Tevatron extraction microcomputer

    International Nuclear Information System (INIS)

    Extraction in the Fermilab Tevatron is controlled by a multi-processor Multibus microcomputer system called QXR (Quad eXtraction Regulator). QXR monitors several analog beam signals and controls three sets of power supplies: the ''bucker'' and ''pulse'' magnets at a rate of 5760 Hz, and the ''QXR'' magnets at 720 Hz. QXR supports multiple slow spills (up to a total of 35 seconds) with multiple fast pulses intermixed. It linearizes the slow spill and bucks out the high frequency components. Fast extraction is done by outputting a variable pulse waveform. Closed loop learning techniques are used to improve performance from cycle to cycle for both slow and fast extraction. The system is connected to the Tevatron clock system so that it can track the machine cycle. QXR is also connected to the rest of the Fermilab control system, ACNET. Through ACNET, human operators and central computers can monitor and control extraction through communications with QXR. The controls hardware and software both employ some standard and some specialized components. This paper gives an overview of QXR as a control system; another paper summarizes performance

  17. Monitoring external beam radiotherapy using real-time beam visualization

    International Nuclear Information System (INIS)

    Purpose: To characterize the performance of a novel radiation therapy monitoring technique that utilizes a flexible scintillating film, common optical detectors, and image processing algorithms for real-time beam visualization (RT-BV). Methods: Scintillating films were formed by mixing Gd2O2S:Tb (GOS) with silicone and casting the mixture at room temperature. The films were placed in the path of therapeutic beams generated by medical linear accelerators (LINAC). The emitted light was subsequently captured using a CMOS digital camera. Image processing algorithms were used to extract the intensity, shape, and location of the radiation field at various beam energies, dose rates, and collimator locations. The measurement results were compared with known collimator settings to validate the performance of the imaging system. Results: The RT-BV system achieved a sufficient contrast-to-noise ratio to enable real-time monitoring of the LINAC beam at 20 fps with normal ambient lighting in the LINAC room. The RT-BV system successfully identified collimator movements with sub-millimeter resolution. Conclusions: The RT-BV system is capable of localizing radiation therapy beams with sub-millimeter precision and tracking beam movement at video-rate exposure

  18. Monitoring external beam radiotherapy using real-time beam visualization

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, Cesare H. [Department of Mechanical Engineering and Department of Radiation Oncology, Stanford University, Stanford, California 94305 (United States); Naczynski, Dominik J.; Yu, Shu-Jung S.; Xing, Lei, E-mail: lei@stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California 94305 (United States)

    2015-01-15

    Purpose: To characterize the performance of a novel radiation therapy monitoring technique that utilizes a flexible scintillating film, common optical detectors, and image processing algorithms for real-time beam visualization (RT-BV). Methods: Scintillating films were formed by mixing Gd{sub 2}O{sub 2}S:Tb (GOS) with silicone and casting the mixture at room temperature. The films were placed in the path of therapeutic beams generated by medical linear accelerators (LINAC). The emitted light was subsequently captured using a CMOS digital camera. Image processing algorithms were used to extract the intensity, shape, and location of the radiation field at various beam energies, dose rates, and collimator locations. The measurement results were compared with known collimator settings to validate the performance of the imaging system. Results: The RT-BV system achieved a sufficient contrast-to-noise ratio to enable real-time monitoring of the LINAC beam at 20 fps with normal ambient lighting in the LINAC room. The RT-BV system successfully identified collimator movements with sub-millimeter resolution. Conclusions: The RT-BV system is capable of localizing radiation therapy beams with sub-millimeter precision and tracking beam movement at video-rate exposure.

  19. Elementary Theory for Optimum Extraction of Space-Charge-Dominated Ion Beams from Plasma Boundaries%受空间电荷效应影响的离子束流从等离子体边界的最佳引出的一阶理论

    Institute of Scientific and Technical Information of China (English)

    G.D.Alton; H.Bilheux

    2007-01-01

    The problem of extracting space-charge-limited ion beams from spherical emission boundaries is analyzed for simple,two electrode,parallel-plate and spherical sector electrode systems by application of Langmuir.Blodgett theory with account taken for the divergent lens effect caused by the aperture in the extraction electrode.Results derived from simulation studies for the three electrode system,designed for use with the Oak Ridge National Laboratory ECR ion source,complement predictions made from elementary analytical theory with or without magnetic field in the extraction region of the source.Under minimum halfangular divergence (minimum emittance) conditions,the plasma emission boundary has an optimum curvature and the perveance,P,(i.e,current density,J+ and extraction gap,d),has an optimum value for a given chargestate.From these studies,we find that the optimum perveance for any electrode system can be determined from the Child-Langmuir relation for the parallel-plate electrode system multiplied by a factor,F with value 0.49≤F≤1.

  20. Development of visual beam adjustment method for cyclotron

    International Nuclear Information System (INIS)

    We have developed a computer-based visual assistance system for JAERI AVF-cyclotron operation. This system provides a CRT display about the cyclotron beam trajectories, feasible setting regions (FSR's), and search traces designed to enhance beam parameter adjustment. As a result of the test in actual operation, it was realized that simulated beam trajectories and FSR's were nearly agreeable with actual beam condition in the axial injection block and the extraction block. (author)

  1. Beam transport

    International Nuclear Information System (INIS)

    The beam diagnostic components for both the transfer and the high-energy beamlines perform well except for some of the scanners whose noise pick-up has become a problem, especially at low beam intensities. This noise pick-up is primarily due to deterioration of the bearings in the scanner. At some locations in the high-energy beamlines, scanners were replaced by harps as the scanners proved to be practically useless for the low-intensity beams required in the experimental areas. The slits in the low-energy beamline, which are not water-cooled, have to be repaired at regular intervals because of vacuum leaks. Overheating causes the ceramic feedthroughs to deteriorate resulting in the vacuum leaks. Water-cooled slits have been ordered to replace the existing slits which will later be used in the beamlines associated with the second injector cyclotron SPC2. The current-measurement system will be slightly modified and should then be much more reliable. 3 figs

  2. External Beam Therapy (EBT)

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z External Beam Therapy (EBT) External beam therapy (EBT) is a ... follow-up should I expect? What is external beam therapy and how is it used? External beam ...

  3. A mathematical model of a three-gap thyratron simulating turn-on

    International Nuclear Information System (INIS)

    Kicker magnets are required for all ring-to-ring transfers in the 5 rings of the proposed KAON factory synchrotron. The kick must rise/fall from 1% to 99% of full strength during the time interval of gaps created in the beam (80 ns to 160 ns) so that the beam can be extracted with minimum losses. Approximately one-third of the injection and extraction kicker magnets will operate continuously at a rate of 50 pulses per second: the others operate at 10 pulses per second. The kicker magnet PFN voltages will be in the range 50kV to 80kV, hence multi-gap thyratrons will be used for the injection and extraction kicker systems. Displacement current arising from turn-on of a multi-gap thyratron flows in the external circuit and can thus increase the effective rise-time of the kick. A mathematical model of a three-gap thyratron, which includes the drift spaces, has been developed for simulating turn-on, and is described in this paper. The thyratron model has been used to investigate ways to suppress the effects of displacement current on the kick, and to reduce thyratron switching loss. A ferrite saturating inductor may be connected adjacent to each thyratron to reduce switching loss, so that thyratron life can be extended and the kick rise-time improved. This inductor can also be used to reduce the effect of anode displacement current during turn-on of a multi-gap thyratron. The research has culminated in a predicted kick rise time (1% to 99%) of less than 50 ns for a TRIUMF 10 cell prototype kicker magnet. The proposed improvements are currently being implemented on our prototype kicker system. (author). 15 refs., 11 figs

  4. Molecular Ion Beam Transportation for Low Energy Ion Implantation

    International Nuclear Information System (INIS)

    A joint research and development of steady state intense boron ion sources for 100's of electron-volt ion implanters has been in progress for the past five years. Current density limitation associated with extracting and transporting low energy ion beams result in lower beam currents that in turn adversely affects the process throughput. The transport channel with electrostatic lenses for decaborane (B10H14) and carborane (C2B10H12) ion beams transportation was developed and investigated. The significant increase of ion beam intensity at the beam transport channel output is demonstrated. The transport channel simulation, construction and experimental results of ion beam transportation are presented.

  5. A cold 87Rb atomic beam

    Institute of Scientific and Technical Information of China (English)

    Wang Xiao-Jia; Feng Yan-Ying; Xue Hong-Bo; Zhou Zhao-Ying; Zhang Wen-Dong

    2011-01-01

    We demonstrate an experimental setup for the production of a beam source of cold 87Rb atoms.The atoms are extracted from a trapped cold atomic cloud in an unbalanced three-dimensional magneto-optical trap.Via a radiation pressure difference generated by a specially designed leak tunnel along one trapping laser beam,the atoms are pushed out continuously with low velocities and a high flux.The most-probable velocity in the beam is varied from 9 m/s to 19 m/s by varying the detuning of the trapping laser beams in the magneto-optical trap and the flux can be tuned up to 4× 109 s-1 by increasing the intensity of the trapping beams.We also present a simple model for describing the dependence of the beam performance on the magneto-optical trap trapping laser intensity and the detuning.

  6. The Continuous Electron Beam Accelerator Facility

    International Nuclear Information System (INIS)

    On February 13, 1987, construction started on the Continuous Electron Beam Accelerator Facility - a 4-GeV, 200-μA, continuous beam, electron accelerator facility designed for nuclear physics research. The machine has a racetrack configuration with two antiparallel, 500-MeV, superconducting linac segments connected by beam lines to allow four passes of recirculation. The accelerating structure consists of 1500-MHz, five-cell niobium cavities developed at Cornell University. A liquid helium cryogenic system cools the cavities to an operating temperature of 2 K. Beam extraction after any three of the four passes allows simultaneous delivery of up to three beams of independently variable currents and different, but correlated, energies to the three experimental areas. Beam breakup thresholds exceed the design current by nearly two orders of magnitude. Project completion and the start of physics operations are scheduled for 1993. The total estimated cost is $255 million

  7. Multiply charged ion beams from solid substances

    International Nuclear Information System (INIS)

    The mVINIS Ion Source has enabled us to obtain multiply charged ion beams from gases as well as from solid materials. The solid substance ion beams were produced by using two techniques: a) the evaporation of metals by using the inlet system based on mini-oven and b) the metal-ions-from volatile-compounds method (MIVOC) by using the modified gas inlet system. In the production of high current stable ion beams of solids with relatively high melting points (over 1000 deg) were made great efforts. The B3+ ion beam current of over 300 μA is one of the most intensive beams extracted until now. The obtained multiply charged ion beam spectra of solid substances (B, Fe and Zn) are presented as well as some of the corresponding experimental results achieved during the modification of polymers, carbon materials and fullerenes. (author)

  8. Beam Loss Studies for the 2-MW LBNE Proton Beam Line

    Energy Technology Data Exchange (ETDEWEB)

    Drozhdin, A.I.; Childress, S.R.; Mokhov, N.V.; Tropin, I.S.; Zwaska, R.; /Fermilab

    2012-05-01

    Severe limits are put on allowable beam loss during extraction and transport of a 2.3 MW primary proton beam for the Long Baseline Neutrino Experiment (LBNE) at Fermilab. Detailed simulations with the STRUCT and MARS codes have evaluated the impact of beam loss of 1.6 x 10{sup 14} protons per pulse at 120 GeV, ranging from a single pulse full loss to sustained small fractional loss. It is shown that loss of a single beam pulse at 2.3 MW will result in a catastrophic event: beam pipe destruction, damaged magnets and very high levels of residual radiation inside and outside the tunnel. Acceptable beam loss limits have been determined and robust solutions developed to enable efficient proton beam operation under these constraints.

  9. Beam quality measure for vector beams.

    Science.gov (United States)

    Ndagano, Bienvenu; Sroor, Hend; McLaren, Melanie; Rosales-Guzmán, Carmelo; Forbes, Andrew

    2016-08-01

    Vector beams have found a myriad of applications, from laser materials processing to microscopy, and are now easily produced in the laboratory. They are usually differentiated from scalar beams by qualitative measures, for example, visual inspection of beam profiles after a rotating polarizer. Here we introduce a quantitative beam quality measure for vector beams and demonstrate it on cylindrical vector vortex beams. We show how a single measure can be defined for the vector quality, from 0 (purely scalar) to 1 (purely vector). Our measure is derived from a quantum toolkit, which we show applies to classical vector beams. PMID:27472580

  10. Phoenix I energy extraction experiment

    International Nuclear Information System (INIS)

    Energy extraction experiments are reported for the Phoenix I amplifier driven by a discharge-initiated oscillator-preamplifier system operating on mixtures of either SF6-HI or SF6-C2H6 and an electron-beam-initiated intermediate amplifer (lambda-3) fueled with H2 and F2 mixtures. When the oscillator-preamplifier system operated with mixtures of SF6-HI the input spectrum to the Phoenix I amplifier contained approx. 28 P-branch vibrational-rotational lines which were almost identical to the input spectrum from the H2-F2 fueled oscillator. In this case the energy extraction measurements were essentially the same as the results obtained with the spectrum produced using H2 and F2 mixtures. For an input intensity of 107 W/cm2, 170 J were extracted from the amplifier. With the SF6-C2H6 spectrum, extraction was only obtained from the first three excited vibrational levels. This result indicates that most of the energy in the amplifier could be extracted on the first three excited vibrational levels. It is shown that the extraction results can be fit with a simple two level model. The radius of curvature of the beam was estimated using a lateral shearing interferometer. It was found that the Phoenix I amplifier altered the radius of curvature

  11. Intense relativistic electron beam: generation and propagation

    International Nuclear Information System (INIS)

    A general review of relativistic electron beam extracted from explosive field emission diode has been presented here. The beam current in the diode gap taking into account cathode and anode plasma expansion velocity and excluding the self magnetic field effect is directly proportional to gap voltage V3/2 and inversely proportional to the square of the effective diode gap (d-vt). In the limit of high current, self magnetic field focusing effect comes into play and results in a critical current at which pinching will take place. When the diode current exceeds the critical current, the electron flow is in the para-potential regime. Different diode geometries such as planner, coaxial, rod-pinched, reflex triode are discussed qualitatively. When the beam is injected into a vacuum drift tube the propagation of the beam is only possible in presence of a strong axial magnetic field which prevents the beam expansion in the radial direction. If the beam is injected in the drift tube filled with dense plasma, then the redistribution of the plasma electrons effectively neutralizes the beam space charge, resulting subsequent propagation of the beam along the drift tube. The beam propagation through neutral gas is similar to the plasma filled drift tube. In this case both the neutral gas pressure and the beam current regulate the transmission of the REB. (author)

  12. Beam propagation

    International Nuclear Information System (INIS)

    The main part of this thesis consists of 15 published papers, in which the numerical Beam Propagating Method (BPM) is investigated, verified and used in a number of applications. In the introduction a derivation of the nonlinear Schroedinger equation is presented to connect the beginning of the soliton papers with Maxwell's equations including a nonlinear polarization. This thesis focuses on the wide use of the BPM for numerical simulations of propagating light and particle beams through different types of structures such as waveguides, fibers, tapers, Y-junctions, laser arrays and crystalline solids. We verify the BPM in the above listed problems against other numerical methods for example the Finite-element Method, perturbation methods and Runge-Kutta integration. Further, the BPM is shown to be a simple and effective way to numerically set up the Green's function in matrix form for periodic structures. The Green's function matrix can then be diagonalized with matrix methods yielding the eigensolutions of the structure. The BPM inherent transverse periodicity can be untied, if desired, by for example including an absorptive refractive index at the computational window edges. The interaction of two first-order soliton pulses is strongly dependent on the phase relationship between the individual solitons. When optical phase shift keying is used in coherent one-carrier wavelength communication, the fiber attenuation will suppress or delay the nonlinear instability. (orig.)

  13. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  14. Development of Cogging at the Fermilab Booster

    CERN Document Server

    Seiya, K; Drennan, C; Pellico, W; Triplett, A K; Waller, A

    2015-01-01

    The development of magnetic cogging is part of the Fermilab Booster upgrade within the Proton Improvement Plan (PIP). The Booster is going to send 2.25E17 protons/hour which is almost double the present flux, 1.4E17 protons/hour to the Main Injector (MI) and Recycler (RR). The extraction kicker gap has to synchronize to the MI and RR injection bucket in order to avoid a beam loss at the rising edge of the extraction and injection kickers. Magnetic cogging is able to control the revolution frequency and the position of the gap using the magnetic field from dipole correctors while radial position feedback keeps the beam at the central orbit. The new cogging is expected to reduce beam loss due to the orbit changes and reduce beam energy loss when the gap is created. The progress of the magnetic cogging system development is going to be discussed in this paper.

  15. Development of Cogging at the Fermilab Booster

    Energy Technology Data Exchange (ETDEWEB)

    Seiya, K. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Chaurize, S. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Drennan, C. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Pellico, W. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Triplett, A. K. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Waller, A. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-01-30

    The development of magnetic cogging is part of the Fermilab Booster upgrade within the Proton Improvement Plan (PIP). The Booster is going to send 2.25E17 protons/hour which is almost double the present flux, 1.4E17 protons/hour to the Main Injector (MI) and Recycler (RR). The extraction kicker gap has to synchronize to the MI and RR injection bucket in order to avoid a beam loss at the rising edge of the extraction and injection kickers. Magnetic cogging is able to control the revolution frequency and the position of the gap using the magnetic field from dipole correctors while radial position feedback keeps the beam at the central orbit. The new cogging is expected to reduce beam loss due to the orbit changes and reduce beam energy loss when the gap is created. The progress of the magnetic cogging system development is going to be discussed in this paper.

  16. A study on beam profile at an industrial electron beam accelerator

    International Nuclear Information System (INIS)

    An industrial type electron beam accelerator located at BARC-BRIT complex, Vashi, Navi Mumbai is operational for development of applications and technology demonstration to the Indian industry in the field of polymer modifications and for processing of various other products. Recently the accelerator has been upgraded from 2 MeV to 5 MeV to process thick polymers, packaged products and for waste water treatment. This accelerator is capable of delivering powered electron beams up to 15 kW average beam power in the energy range 3 to 5 MeV. In the facility, product is irradiated either in static or conveyor mode of operation under the scanning- type beam. In the present work, we have performed beam profile measurement at different distances from the beam extraction window under conveyor and static mode of operation. We have used cellulose triacetate (CTA) strip dosimeters for the beam profile measurement. Dose profile measured along the scan direction (beam width) in conveyor mode and beam length profile in static mode of operation at different distances below accelerator beam exit window is shown. In the conveyor mode of operation, as the distance increases from the beam window the uniformity of the dose distribution improves but dose decreases linearly with distance. For a scanned beam, the beam width defines the dimension of the beam sweep. For static mode of operation, the dose from the exit window of the accelerator follows inverse relation with distance (i.e. l/r). This shows that the system is a line-type directional radiation source. Beam length is critical for processes where product is stationary under the beam and also for setting speed of the conveyor depending on pulse frequency in conveyor mode of operation. The present paper describes optimization of operational parameters to maximize the efficiency of the irradiation process based on these measurements. (author)

  17. Optimization of a charge-state analyzer for ECRIS beams

    CERN Document Server

    Saminathan, S; Kremers, H R; Mironov, V; Mulder, J; Brandenburg, S

    2012-01-01

    A detailed experimental and simulation study of the extraction of a 24 keV He-ion beam from an ECR ion source and the subsequent beam transport through an analyzing magnet is presented. We find that such a slow ion beam is very sensitive to space-charge forces, but also that the neutralization of the beam's space charge by secondary electrons is virtually complete for beam currents up to at least 0.5 mA. The beam emittance directly behind the extraction system is 65 pi mm mrad and is determined by the fact that the ion beam is extracted in the strong magnetic fringe field of the ion source. The relatively large emittance of the beam and its non-paraxiality lead, in combination with a relatively small magnet gap, to significant beam losses and a five-fold increase of the effective beam emittance during its transport through the analyzing magnet. The calculated beam profile and phase-space distributions in the image plane of the analyzing magnet agree well with measurements. The kinematic and magnet aberrations...

  18. Two 352 MHz push pull linac pairs to generate two drive beams for CLIC multibunch operation

    International Nuclear Information System (INIS)

    90 deg. arcs and no fast kickers. The drive beam generation process thus occur over a limited and almost the straight length of about 1 km including superconducting cavities, magnets and straight sections. b) acceleration in mainly large-aperture 352 MHz superconducting structures causing low wakes. (Y. Tanaka)

  19. Stable atomic hydrogen: Polarized atomic beam source

    International Nuclear Information System (INIS)

    We have carried out experiments with stable atomic hydrogen with a view to possible applications in polarized targets or polarized atomic beam sources. Recent results from the stabilization apparatus are described. The first stable atomic hydrogen beam source based on the microwave extraction method (which is being tested ) is presented. The effect of the stabilized hydrogen gas density on the properties of the source is discussed. (orig.)

  20. Plasma studies and beam emittance measurements of 2.45 GHz microwave ion source at VECC

    International Nuclear Information System (INIS)

    A 2.45 GHz microwave ion source operating at VECC is able to produce a total beam current of ∼ 12 mA at a beam energy of 75 KeV with a microwave power of 400 W as described in. In order to optimize the performance of the ion source, we have conducted systematic studies with the variation of ion source gas flow rate, magnetic field, extraction voltage, suppressor voltage, microwave power etc. The total extracted beam current was recorded as a function of each of the earlier mentioned parameters. Moreover, we have studied the effect on extracted beam current and its transmission in the beam transport line due to dielectric and water introduction into the plasma chamber. In the best setting, we have found a total extracted beam current of 12.5 mA with a beam transmission of 70 %. Furthermore, we have also studied the extracted beam current and its transmission in the beam transport line using aluminum plasma chamber of different diameters. Finally, we have estimated the beam emittance by solenoid scan technique of a neutralized 75 KeV, 5 mA proton beam by measuring beam profile using a non-interceptive residual gas fluorescence monitor. The measured normalized rms emittance of the neutralized beam is 0.05 mm-mrad, which seems to be quite reasonable. (author)