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Sample records for beam extraction kicker

  1. REDUCING BEAM COUPLING IMPEDANCES IN SNS RING EXTRACTION KICKERS

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S. (Sergey); Davino, D. (Daniele); Lee, Y. Y.

    2001-01-01

    The Spallation Neutron Source (SNS) Accumulator ring extraction system includes 14 modules of windowframe ferrite pulsing kicker magnets with the rise time of about 200 ns. Their contribution to the beam coupling impedances is a serious concern. The kicker impedances, as well as its deflecting magnetic field versus time, are studied using detailed 3-D MAFIA modeling. Various design options, external circuit resistances, and a range of ferrite permeabilities are explored. A kicker module with wide conductor windings around the ferrite behind the kicker current sheet suggests a significant reduction of the kicker transverse and longitudinal coupling impedances. This design provides a good extraction field performance, as demonstrated by electromagnetic simulations. Results of measurements for a small model are also presented.

  2. REDUCING BEAM COUPLING IMPEDANCES IN SNS RING EXTRACTION KICKERS.

    Energy Technology Data Exchange (ETDEWEB)

    KURENNOY,S.S.; DAVINO,D.; LEE,Y.Y.

    2001-06-18

    The Spallation Neutron Source (SNS) Accumulator ring extraction kickers [1] consists of 14 modules of windowframe ferrite pulsing magnets with the rise time of about 200 ns. Their contribution to the beam coupling impedances is a serious concern. The kicker impedances, as well as its deflecting magnetic field versus time, are studied using detailed 3-D MAFIA modeling. Various design options, external circuit resistances, and a range of ferrite permeabilities are explored. A kicker module with wide conductor windings around the ferrite behind the kicker current sheet suggests a significant reduction of the kicker transverse and longitudinal coupling impedances. This design provides a good extraction field performance, as demonstrated by electromagnetic simulations. Results of measurements for a small model are also presented.

  3. REDUCING BEAM COUPLING IMPEDANCES IN SNS RING EXTRACTION KICKERS

    Energy Technology Data Exchange (ETDEWEB)

    S.S. KURENNOY; D. DAVINO; Y. LEE

    2001-06-01

    The Spallation Neutron Source (SNS) Accumulator ring extraction system [1] includes 14 modules of window-frame ferrite pulsing kicker magnets with the rise time of about 200 ns. Their contribution to the beam coupling impedances is a serious concern. The kicker impedances, as well as its deflecting magnetic field versus time, are studied using detailed 3-D MAFIA modeling. Various design options, external circuit resistances, and a range of ferrite permeabilities are explored. A kicker module with wide conductor windings around the ferrite behind the kicker current sheet suggests a significant reduction of the kicker transverse and longitudinal coupling impedances. This design provides a good extraction field performance, as demonstrated by electromagnetic simulations. Results of measurements for a small model are also presented.

  4. Beam Coupling Impedances of Traveling-Wave Ferrite-Free Extraction Kickers

    Science.gov (United States)

    Kurennoy, Sergey

    2002-04-01

    Fast traveling-wave extraction kickers contain no ferrite and consist of two long metallic parallel plates supported by insulators inside a beam pipe. A beam is deflected by both the electric and magnetic fields of a TEM wave created by a pulse propagating along the strips in the direction opposite to the beam. Computations of the beam coupling impedances for such structures are difficult because of their length. In the paper, the beam coupling impedances of such transmission-line kickers are calculated by combining analytical and numerical methods: the wake potentials computed in short models are extended analytically to obtain the wakes for the long kickers, and then the corresponding beam impedances are derived. As one can expect, at very low frequencies the results are in agreement with simple analytical expressions available for the coupling impedances of striplines in beam position monitors.

  5. 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...

  6. 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)

  7. 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...

  8. SPS extraction kicker magnet thermal analysis

    CERN Document Server

    Timmins, M

    2004-01-01

    As the SPS accelerator will be used for the CNGS project and as LHC injector, the proton beams passing through its extraction kickers will have a much higher intensity than in the past. The image currents generated by this beam may provoke a temperature increase in the magnet's ferrite core to temperatures above the Curie temperature, unless the heat produced is effectively removed. A further complication arises from the fact that a high voltage is applied to the ferrites. The solution adopted consists in transferring the heat via Aluminium Nitride insulators to a water cooling circuit. The heat transfer analysis and the calculated thermal distribution of the magnet are presented.

  9. 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.

  10. 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.

  11. 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 ...

  12. Beam coupling impedances of fast transmission-line kickers.

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S. (Sergey)

    2002-01-01

    Fast transmission-line kickers contain no ferrite and consist of two long metallic parallel plates supported by insulators inside a beam pipe. A beam is deflected by both the electric and magnetic fields of a TEM wave created by a pulse propagating along the strips in the direction opposite to the beam. Computations of the beam coupling impedances for such structures are difficult because of their length. In the paper, the beam coupling impedances of transmission-line kickers are calculated by combining analytical and numerical methods: the wake potentials computed in short models are extended analytically to obtain the wakes for the long kickers, and then the corresponding beam impedances are derived. At very low frequencies the results are compared with simple analytical expressions for the coupling impedances of striplines in beam position monitors.

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

    Science.gov (United States)

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

    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)

  14. 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...

  15. A Retrofit Technique for Kicker Beam-Coupling Impedance Reduction

    CERN Document Server

    Caspers, Friedhelm; Kroyer, T; Timmins, M; Uythoven, J; Kurennoy, S

    2004-01-01

    The reduction of the impedance of operational ferrite kicker structures may be desirable in order to avoid rebuilding such a device. Often resistively coated ceramic plates or tubes are installed for this purpose but at the expense of available aperture. Ceramic U-shaped profiles with a resistive coating fitting between the ellipse of the beam and the rectangular kicker aperture have been used to significantly reduce the impedance of the magnet, while having a limited effect on the available physical aperture. Details of this method, constraints, measurements and simulation results as well as practical aspects are presented and discussed.

  16. 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

  17. Design and Manufacturing Description of the Prototype Striplines for the Extraction Kicker of the CLIC Damping Rings

    CERN Document Server

    Belver-Aguilar, C; Faus-Golfe, A; Gómez, J; Gutiérrez, D; Toral, F

    2013-01-01

    The Pre-Damping Rings (PDRs) and Damping Rings (DRs) of CLIC are needed to reduce the beam emittances to the small values required for the main linacs. The injection and extraction, from the PDRs and DRs, are carried out by kicker systems. In order to achieve both low beam coupling impedance and reasonable broadband impedance matching to the electrical circuit, striplines have been chosen for the kicker elements. The design of the stripline kicker was previously carried out by modelling the striplines with simulation codes such as HFSS, Quickfield and CST Particle Studio. In order to have a complete analysis of the striplines, the effect of electrode supports and coaxial feedthroughs have been studied in detail. In this paper, electromagnetic analyses of the complete striplines, including fabrication tolerances, are reported. Furthermore, a new idea for impedance matching is presented.

  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. 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.

  20. 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.

  1. BEAM DYNAMICS ANALYSIS FOR THE ULTRA-FAST KICKER IN CIRCULAR COOLER RING OF JLEIC

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Yulu [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Inst. Modern Phys., Chinese Academy of Sciences, Lanzhou, China; Wang, Haipeng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Rimmer, Robert A. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wang, Shaoheng [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-05-01

    An ultra-fast kicker system consisting of four quarter wavelength resonator based deflecting cavities was developed that simultaneously resonates at 10 subharmonic modes of the 476.3MHz bunch repetition frequency. Thus every 10th bunch in the bunch train will experience a transverse kick while all the other bunches are undisturbed. This fast kicker is being developed for the Energy Recovery Linac (ERL) based electron Circular Cooler Ring (CCR) in the proposed Jefferson Lab Electron Ion Collider (JLEIC, previously MEIC). The electron bunches can be reused 10-30 turns thus the beam current in the ERL can be reduced to 1/10 - 1/30 (150mA - 50mA) of the cooling bunch current (1.5A). In this paper, several methods to synthesize such a kicker waveform and the comparison made by the beam dynamics tracking in Elegant will be discussed.

  2. Kicker impedance measurements for the future multiturn extraction of the CERN Proton Synchrotron

    CERN Document Server

    Métral, Elias; Giovannozzi, Massimo; Grudiev, Alexei; Kroyer, Tom; Sermeus, Luc

    2006-01-01

    In the context of the novel multi-turn extraction, where charged particles are trapped into stable islands in transverse phase space, the ejection of five beamlets will be performed by means of a set of three new kickers. Before installing them into the machine, a measurement campaign has been launched to evaluate the impedance of such devices. Two measurement techniques were used to try to disentangle the driving and detuning impedances. The first consists in measuring the longitudinal impedance for different transverse offsets using a single displaced wire. The sum of the transverse driving and detuning impedances is then deduced applying Panofsky- Wenzel theorem. The second uses two wires excited in opposite phase and yields the driving transverse impedance only. Finally, the consequences on the beam dynamics are also analyzed.

  3. 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...

  4. Upgrade and Tests of the SPS Fast Extraction Kicker System for LHC and CNGS

    CERN Document Server

    Gaxiola, E; Burkel, P; Carlier, E; Castronuovo, F; Ducimetière, L; Sillanoli, Y; Timmins, M; Uythoven, J

    2004-01-01

    A fast extraction kicker system has been installed in the SPS and successfully used in extraction tests in 2003. It will serve to send beam to the anticlockwise LHC ring and the CNGS neutrino facility. The magnets and pulse generators have been recuperated from an earlier installation and upgraded to fit the present application. Hardware improvements include diode stacks as replacement of the previous dump thyratron switches, a cooling system of the magnets, sensors for its ferrite temperatures and magnetic field quality assessment. In preparation of the future use for 450 GeV/c transfer to LHC and double batch extraction at 400 GeV/c for CNGS the tests comprised extractions of single bunches, twelve bunches in a single extraction and single bunches in a double extraction. The measured kick characteristics of the upgraded system are presented, along with a discussion of Pspice simulation results. Further improvements will be discussed which are intended to make the system comply with the specifications for CN...

  5. NuMI Proton Kicker Extraction Magnet Termination Resistor System

    CERN Document Server

    Reeves, Scott

    2005-01-01

    The temperature stability of the kicker magnet termination resistor assembly directly affects the field flatness and amplitude stability of the kick. Comprehensive thermal enhancements were made to the existing Main Injector resistor assembly design to satisfy NuMI performance specifications. Additionally, a fluid-processing system utilizing Fluorinert® FC-77 high-voltage dielectric was built to precisely control the setpoint temperature of the resistor assembly from 70 to 120F, required to maintain constant resistance during changing operational modes. The Fluorinert® must be continually processed to remove hazardous breakdown products caused by radiation exposure to prevent chemical attack of system components. Design details of the termination resistor assembly and Fluorinert® processing system are described. Early performance results will be presented.

  6. 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...

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. Solid State Switch Application for the LHC Extraction Kicker Pulse Generator

    CERN Document Server

    Carlier, E; Jansson, U; Schlaug, M; Schröder, G; Vossenberg, Eugène B

    1996-01-01

    A semiconductor solid state switch has been constructed and tested in the prototype extraction kicker pulse generator of CERN's Large Hadron Collider (LHC) [1]. The switch is made of 10 modified 4.5 kV, 66 mm symmetric GTO's (also called FHCT-Fast High Current Thyristor), connected in series. It holds off a d.c. voltage of 30 kV and conducts a 5 µs half-sine wave current of 20 kA with an initial di/dt of 10 kA/µs. Major advantages of the switch are the extremely low self-firing hazard, no power consumption during the ready-to-go status, instantaneous availability, simple condition control, very low noise emission during soft turn-on switching and easy maintenance. However, the inherent soft, relatively slow turn-on time is a non negligible part of the required rise time and this involves adaptation of generator components. A dynamic current range of 16 is achieved with variations in rise time, which stay within acceptable limits. Important generator improvements have been made with the series diodes and fre...

  13. 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...

  14. 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

  15. 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.

  16. 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)

  17. 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.

  18. Concept for ELENA Extraction and Beam Transfer Elements

    CERN Document Server

    Borburgh, J; Balhan, B; Barna, D; Bartmann, W; Fowler, T; Pricop, V; Sermeus, L; Vanbavinckhove, G

    2013-01-01

    In 2011 the ELENA decelerator was approved as a CERN project. Initially one extraction was foreseen, which should use a kicker and a magnetic septum which can be recuperated from an earlier installation. Since then a second extraction has been approved and a new solution was studied using only electric fields to extract the beam. This will be achieved by fast pulsing a separator, allowing single-bunch but also a full single-turn extraction from ELENA towards the experiments. The extraction and transfer requirements of ELENA are described, followed by the principal differences between the magnetic and electric field concepts. The design of electrostatic focussing and bending devices for the transfer lines will be presented. Finally the field quality which can be achieved with the separator and the concept of its power supply will be discussed.

  19. Magnetic Field Measurement on a Refined Kicker

    CERN Document Server

    Fan, Tai-Ching; Lin, Fu-Yuan

    2005-01-01

    To prepare for the operation of top-up mode and increase the efficiency of injection at storage ring, National Synchrotron Radiation Research Center (NSRRC) has upgraded the kicker magnets and power supply. We have built up a new magnetic field measurement system to test the kicker. This system, including a search coil and a coil loop, can map the field and take the first integral of field automatically. We also simulate the trajectory of electron beam by pulsed wire method of field measurement. We analyze the performance of the kicker system in this paper.

  20. 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...

  1. Using a ceramic chamber in kicker magnets

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S.

    1993-05-01

    A ceramic chamber inside kicker magnets can provide the relevant field risetime. On the other hand, some metallic coating inside has to prevent static charge buildup and shield the beam from ceramic and ferrite at high frequencies to avoid possible resonances. The issues concerning the metallized ceramic chamber, such as coupling impedances and requirements on the coating, are studied to find a compromise solution for kickers of the Medium Energy Booster at the Superconducting Super Collider.

  2. 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.

  3. 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 ...

  4. 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.

  5. 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.

  6. 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}.

  7. 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}.

  8. 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...

  9. Targets and Secondary Beam Extraction

    Science.gov (United States)

    Noah, Etam

    2014-02-01

    Several applications make use of secondary beams of particles generated by the interaction of a primary beam of particles with a target. Spallation neutrons, bremsstrahlung photon-produced neutrons, radioactive ions and neutrinos are available to users at state-of-the-art facilities worldwide. Plans for even higher secondary beam intensities place severe constraints on the design of targets. This article reports on the main targetry challenges and highlights a variety of solutions for targetry and secondary beam extraction. Issues related to target station layout, instrumentation at the beam-target interface, safety and radioprotection are also discussed.

  10. 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...

  11. Calculation of Metallization Resistivity and Thickness for MedAustron Kickers

    CERN Document Server

    Barnes, M J; Stadlbauer, 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 facility. The kicker magnets are outside machine vacuum: each kicker magnet has a ceramic beam chamber whose inner surface is metalized. The resistivity and thickness of the metallization are chosen such that the induced eddy currents, resulting from the pulsed kicker magnetic field, do not unduly affect the rise/fall times or homogeneity of the magnetic field. A comparison of an analytical calculation and measurement is reported for the effect of metallization of a ceramic chamber in an existing kicker system at CERN. Conclusions concerning the metallization of the ceramic chambers for the MedAustron kicker magnets are presented.

  12. 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).

  13. 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.

  14. 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.

  15. 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...

  16. 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

  17. Investigation of Planar Pick-up and Kicker Electrodes for Stochastic Cooling

    CERN Document Server

    Balk, M; Weiland, T; Nolden, F; Caspers, Friedhelm

    2002-01-01

    The success of stochastic cooling crucially depends on the interaction between the beam and high frequency devices for detection (pick-up electrodes) and deflection (kicker electrodes). This contribution shows the theoretical investigation of a planar electrode to be used for stochastic cooling of secondary particles with a beta of 0.83. The coupling to the beam is realised by a slot line. Transition networks are added to extract the signal. The detailed investigation is performed via a numerical electromagnetic field analysis. The longitudinal kick of the deflectors is calculated as a function of the beam position and scaled to the applied voltage. According to the Panofsky-Wenzel theorem the transverse kick is obtained simultaneously. The electromagnetic properties of the discussed electrode are compared to existing ones as currently in use in the ESR storage ring (GSI, Darmstadt).

  18. 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...

  19. 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...

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

    CERN Document Server

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

    2005-01-01

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

  1. 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

  2. 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.

  3. 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.

  4. 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.

  5. SPS Beam Steering for LHC Extraction

    Energy Technology Data Exchange (ETDEWEB)

    Gianfelice-Wendt, Eliana [Fermilab; Bartosik, Hannes [CERN; Cornelis, Karel [CERN; Norderhaug Drøsdal, Lene [CERN; Goddard, Brennan [CERN; Kain, Verena [CERN; Meddahi, Malika [CERN; Papaphilippou, Yannis [CERN; Wenninger, Jorg [CERN

    2014-07-01

    The CERN Super Proton Synchrotron accelerates beams for the Large Hadron Collider to 450 GeV. In addition it produces beams for fixed target facilities which adds complexity to the SPS operation. During the run 2012-2013 drifts of the extracted beam trajectories have been observed and lengthy optimizations in the transfer lines were performed to reduce particle losses in the LHC. The observed trajectory drifts are consistent with the measured SPS orbit drifts at extraction. While extensive studies are going on to understand, and possibly suppress, the source of such SPS orbit drifts the feasibility of an automatic beam steering towards a “golden” orbit at the extraction septa, by means of the interlocked correctors, is also being 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.

  6. 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.

  7. 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

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. STRIPLINE KICKER DESIGN FOR NSLS2 STORAGE RING

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, W.; Blednykh, A.; Krinsky, S.; Singh, O.

    2011-03-28

    In the NSLS2 storage ring, there are four stripline kickers/pickups. Two long striplines with electrode length of 30cm will be used as bunch-by-bunch transverse feedback actuators. Two short stripline kickers/pickups with 15cm length will mainly used for tune measurement excitation or signal pickup for the beam stability monitor. High shunt impedance of the long stripline kickers is demanded to produce 200 {micro}s damping time. Meanwhile the beam impedance should be minimized. The design work for these two types of stripline is discussed in this paper. NSLS2 is a third-generation light source under construction at Brookhaven National Laboratory. The machine will have < 1nm.rad horizontal emittance by using weak dipoles together with damping wigglers. For the storage ring of 792m circumference, geometric impedance, resistive wall impedance and ion effects are expected to be significant. A transverse bunch-by-bunch feedback system has been designed to suppress the coupled bunch instabilities. More information can be found in previous paper.

  13. 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...... 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......) 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....

  14. 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.

  15. 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)

  16. 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.

  17. 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

  18. 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

  19. 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.

  20. THE EXTRACTION LAMBERTSON SEPTUM MAGNET OF THE SNS.

    Energy Technology Data Exchange (ETDEWEB)

    RANK J.; MIGLIONICO, G.; RAPARIA, D.; TSOUPAS, N.; TUOZZOLO, J.; LEE, Y.Y.

    2005-05-16

    In the Spallation Neutron Source, after multiple injections to an accumulator ring, a final extraction delivers the full proton beam to the target, achieved by a series of kickers and a thin septum magnet. Here we discuss the lattice geometry, beam dynamics and optics, and the vacuum, electromagnetic and mechanical design aspects of the Extraction Lambertson Septum Magnet (ELS). Relevant data are established. Vector calculus is solved for pitch and roll angles, which are shown schematically in magnet sections.

  1. 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.

  2. 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.

  3. 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

  4. LHC beam dumping system Extraction channel layout and acceptance

    CERN Document Server

    Goddard, B; Uythoven, J; Veness, R; Weterings, W

    2003-01-01

    The LHC beam dumping system must safely abort the LHC beams under all conditions, including those resulting from abnormal behaviour of machine elements or subsystems of the beam dumping system itself. The extraction channels must provide sufficient aperture both for the circulating and extracted beams, over the whole energy range and under various beam parameters. These requirements impose tight constraints on the tolerances of various extraction channel components, and also on the allowed range of beam positions in the region of these components. Operation of the beam dumping system under various fault states has been considered, and the resulting apertures calculated. After describing briefly the beam dumping system and the extraction channel geometry, the various assumptions made in the analysis are presented, before deriving tolerance limits for the relevant equipment and beam parameters.

  5. 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.

  6. 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

  7. 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...

  8. 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.

  9. Energy compensation of slow extracted beams with RF acceleration

    Science.gov (United States)

    Fujimoto, Tetsuya; Souda, Hikaru; Torikoshi, Masami; Kanai, Tatsuaki; Yamada, Satoru; Noda, Koji

    2016-03-01

    In a conventional carbon-ion radiotherapy facility, a carbon-ion beam is typically accelerated up to an optimum energy, slowly extracted from a synchrotron ring by a resonant slow extraction method, and ultimately delivered to a patient through a beam-delivery system. At Japan's Gunma University, a method employing slow-beam extraction along with beam-acceleration has been adopted. This method slightly alters the extracted-beam's energy owing to the acceleration component of the process, which subsequently results in a residual-range variation of approximately 2 mm in water-equivalent length. However, this range variation does not disturb a distal dose distribution with broad-beam methods such as the single beam-wobbling method. With the pencil-beam 3D scanning method, however, such a range variation disturbs a distal dose distribution because the variation is comparable to slice thickness. Therefore, for pencil-beam 3D scanning, an energy compensation method for a slow extracted beam is proposed in this paper. This method can compensate for the aforementioned energy variances by controlling net energy losses through a rotatable energy absorber set fixed between the synchrotron exit channel and the isocenter. Experimental results demonstrate that beam energies can be maintained constant, as originally hypothesized. Moreover, energy-absorber positions were found to be significantly enhanced by optimizing beam optics for reducing beam-size growth by implementation of the multiple-scattering effect option.

  10. 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.

  11. 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

  12. A Wideband Slotted Kicker Design for SPS Transverse Intra-Bunch Feedback

    CERN Document Server

    Cesaratto, John M; DeSantis, S; Drago, A; Fox, J D; Gallo, A; Hofle, W; Marcellini, F; Rivetta, C H; Zobov, M

    2013-01-01

    Control and mitigation of transverse beam instabilities caused by electron cloud and TMCI will be essential for the SPS to meet the beam intensity demands for the HL-LHC upgrade. A wideband intra-bunch feedback method is in development, based on a 4 GS/s data acquisition and processing, and with a back end frequency structure extending to 1 GHz. A slotted type kicker, similar to those used for stochastic cooling, has been considered as the terminal element of the feedback chain. It offers the most promising deflecting structure characteristics to meet the system requirements in terms of bandwidth, shunt impedance, and beam coupling impedance. Different types of slotted structures have been explored and simulated, including a ridged waveguide and coaxial type waveguide. In this paper we present our findings and the conceptual design of a vertical SPS wideband kicker consistent with the stay clear, vacuum, frequency band coverage, and peak shunt impedance requirements.

  13. 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.

  14. 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 ion beam with low beam emittance and high brightness.The simulation process can provide a good study for optimizing the extraction and focusing system of the ion beam without any losses and transported to the required target.Also,a study of a simulation model for the extraction system of the ion source was used to describe the possible plasma boundary curvatures during the ion extraction that may be affected by the change in an extraction potential with a constant plasma density meniscus.

  15. Turn-By Beam Extraction during Acceleration in a Synchrotron

    Science.gov (United States)

    Tsoupas, Nicholaos; Trbojevic, Dejan

    2014-02-01

    A synchrotron to accelerate protons or carbon ions for medical applications is being designed at Brookhaven National Laboratory (BNL). Single beam bunches with maximum beam energy of 1.18 GeV and 400 MeV/u for protons and carbon ions respectively will be extracted from the synchrotron at 15 Hz. For protons, the maximum required energy for irradiating a tumor is ˜206 MeV. A pencil-like proton beam containing ˜5.4×107 p/bunch delivers a therapeutic dose of 2.5 Gy in ˜1.5 minutes to treat a tumor of 1 liter volume. It will take ˜80 minutes with bunches containing 4.5×104 ions/bunch to deliver the same dose of 2.5 Gy with a 400 MeV/u pencil-like carbon beam. This extended treatment time when using carbon ions is not acceptable. In addition, the synchrotron cannot be controlled with a beam bunch containing such a low number of carbon ions. To overcome these two problems of the extended treatment time and the low bunch intensity required for the treatment when carbon ions are used, we have devised a method to “peel” the required 4.5×104 carbon-ions/bunch from the accelerating carbon beam bunch containing ˜108 ions/bunch and deliver them to the tumor on a “turn-by-turn” basis. Unlike other methods of beam extraction from a synchrotron, such as resonance extraction, this method does not allow for any beam losses during the extraction and the carbon beam can be peeled off in less than 15 ms during the acceleration or deceleration cycle of the synchrotron. Thus, this turn-by-turn beam extraction method provides beam with variable energy and precisely controlled beam current during the 30 ms acceleration or deceleration time.

  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. 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.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. FLUKA Simulation of Particle Fluences to ALICE due to LHC Injection Kicker Failures

    CERN Document Server

    Shetty, N V; Di Mauro, A; Lechner, A; Leogrande, E; Uythoven, J

    2014-01-01

    The counter-rotating beams of the LHC are injected in insertion regions which also accommodate the ALICE and LHCb experiments. An assembly of beam absorbers ensures the protection of machine elements in case of injection kicker failures, which can affect either the injected or the stored beam. In the first years of LHC operation, secondary particle showers due to beam impact on the injection beam stopper caused damage to the MOS injectors of the ALICE silicon drift detector as well as high-voltage trips in other ALICE subdetectors. In this study, we present FLUKA [1,2] simulations of particle fluences to the ALICE cavern for injection failures encountered during operation. Two different cases are reported, one where the miskicked beam is fully intercepted and one where the beam grazes the beam stopper.

  3. 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)

  4. 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

  5. Dynamic structural analysis of the TPSG4 & TPSG6 beam diluters

    CERN Document Server

    Massidda, L; Kadi, Y; Balhan, B

    2005-01-01

    In this report we present the technical specification for the numerical model and the study of the dynamic structural behaviour of the beam diluter elements (TPSG4 & 6) protecting the extraction septum magnets (MSE & MST) in the event of an asynchronous firing of the extraction kickers (MKE). The deposited energy densities, estimated by the high-energy particle transport code FLUKA, were converted to internal heat generation rates according to the time dependence of the extracted beam. The transient response to this thermal load was obtained by solving the power deposition and structural deformation problem by the spectral-element code ELSE.

  6. 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.

  7. The PS Booster's ejection kicker: full house.

    CERN Multimedia

    1971-01-01

    The modules of the Booster's four-storied full-aperture kicker pretty much fill their vacuum tank (front cover removed). In the original 800 MeV version, the delay-type modules were pulsed at 30 kV from a Pulse-Forming-Network (PFN), yielding a field risetime as short as 60 ns. The fieldstrength was 0.1 T at a current of 1200 A. The modules are made from steel plates and ferrite slabs. The ferrite's high initial outgassing rate presented a serious vacuum problem for a long time.

  8. 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)

  9. 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

  10. 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...

  11. DESIGN OF BEAM-EXTRACTION SEPTUM MAGNET FOR THE SNS.

    Energy Technology Data Exchange (ETDEWEB)

    TSOUPAS,N.; LEE,Y.Y.; RANK,J.; TUOZZOLO,J.

    2001-06-18

    The beam-extraction process from the SNS accumulator ring [1,2] requires a Lambertson septum magnet. In this paper we discuss the geometrical and magnetic field requirements of the magnet and present results obtained from two and three dimensional magnetic field calculations that shows the field quality in the regions of interest of the septum magnet.

  12. TANGO standard software to control the Nuclotron beam slow extraction

    Science.gov (United States)

    Andreev, V. A.; Volkov, V. I.; Gorbachev, E. V.; Isadov, V. A.; Kirichenko, A. E.; Romanov, S. V.; Sedykh, G. S.

    2016-09-01

    TANGO Controls is a basis of the NICA control system. The report describes the software which integrates the Nuclotron beam slow extraction subsystem into the TANGO system of NICA. Objects of control are power supplies for resonance lenses. The software consists of the subsystem device server, remote client and web-module for viewing the subsystem data.

  13. 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.

  14. 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.

  15. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, P.; /Queen Mary, U. of London; Christian, G.B.; Hartin, A.F.; Dabiri Khah, H.; White, G.R.; /Oxford U.; Clarke, C.C.; Perry, C.; /Oxford Instruments; Kalinin, A.; /Daresbury; McCormick, D.J.; Molloy, S.; Ross, M.C.; /SLAC

    2007-04-16

    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.

  17. 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

  18. Pulse Power Modulator development for the CLIC Damping Ring Kickers

    CERN Document Server

    Holma, Janne

    2012-01-01

    The Compact Linear Collider (CLIC) study is exploring the scheme for an electron-positron collider with high luminosity (10-34 – 10-35 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 Pre-Damping Rings (PDR) and Damping Rings (DR) to achieve the very low emittance, through synchrotron radiation, needed for the luminosity requirements of CLIC. To limit the beam emittance blow-up due to oscillations, the pulse power modulators for the DR kickers must provide extremely flat, high-voltage pulses: the 2 GHz specification called for a 160 ns duration flat-top of 12.5 kV, 250 A, with a combined ripple and droop of not more than ±0.02 %. In order to meet these demanding specifications, a combination of broadband impedance matching, optimized electrical circuit layout and advanced control techniques is required. A solid-state modulator, the inductive adder, is the most promising approach to meeting the demanding specifications...

  19. 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 ...

  20. 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.

  1. 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.

  2. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, Natsuko, E-mail: fujita.natsuko@jaea.go.jp [Graduate School of Humanities and Sciences, Nara Women’s University, Nara, 630 8506 (Japan); Yamaki, Atsuko [Graduate School of Humanities and Sciences, Nara Women’s University, Nara, 630 8506 (Japan); Ishii, Kunikazu; Ogawa, Hidemi [Department of Physics, Nara Women’s University, Nara, 630 8506 (Japan)

    2013-11-15

    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.

  4. 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.

  5. EM Simulations in Beam Coupling Impedance Studies: Some Examples of Application

    CERN Document Server

    Zannini, C

    2012-01-01

    In the frame of the SPS upgrade an accurate impedance model is needed in order to predict the instability threshold and if necessary to start a campaign of impedance reduction. Analytical models, 3-D simulations and bench measurements are used to estimate the impedance contribution of the different devices along the machine. Special attention is devoted to the estimation of the impedance contribution of the kicker magnets that are suspected to be the most important impedance source in SPS. In particular a numerical study is carried out to analyze the effect of the serigraphy in the SPS extraction kicker. An important part of the devices simulations are the ferrite model. For this reason a numerical based method to measure the electromagnetic properties of the material has been developed to measure the ferrite properties. A simulation technique, in order to account for external cable is developed. The simulation results were benchmarked with analytical models and observations with beam. A numerical study was a...

  6. Kicker磁铁电源控制系统设计%Design of Control System for Kicker Magnet Power Supply

    Institute of Scientific and Technical Information of China (English)

    郭玉辉; 王彦瑜; 周德泰; 刘伍丰

    2013-01-01

    兰州重离子加速器冷却储存环包含多个注入和引出环节,其中较为关键的是CSRm的引出和CSRe的注入系统,其时间控制精度直接影响束流的注入引出效率.本文采用先进的ARM+ FPGA技术实现对踢轨电源系统的精确控制,其时间控制精度达ns量级.ARM主要实现控制数据的下载与上传,踢轨系统的控制时序主要通过FPGA编程完成.远程时序控制信号均通过光纤传输,同时对踢轨电源的电压给定采用数字电位器技术实现,给定精度达0.1%.%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 %.

  7. 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

  8. 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...

  9. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Burrows, P.; /Queen Mary, U. of London; Christian, G.B.; Hartin, A.F.; Dabiri Khah, H.; White, G.R.; /Oxford U.; Clarke, C.C.; Perry, C.; /Oxford Instruments; Kalinin, A.; /Daresbury; McCormick, D.J.; Molloy, S.; Ross, M.C.; /SLAC

    2007-04-16

    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. 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

  12. 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

  13. 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.

  14. 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.

  15. 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

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

    Science.gov (United States)

    Zou, Ye; Tang, Jingyu; Yang, Zheng; Jing, Hantao

    2014-02-01

    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 2×104 protons per cycle or 5×105 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.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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 ...

  9. On the energy dependence of proton beam extraction with a bent crystal

    CERN Document Server

    Arduini, Gianluigi; Fidecaro, Giuseppe; Gyr, Marcel; Herr, Werner; Klem, J T; Mikkelsen, U; Weisse, E

    1998-01-01

    Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators.

  10. 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.

  11. Magnet Design for the ISIS Second Target Station Proton Beam Line

    CERN Document Server

    Thomas, Chris; Jago, Stephen

    2005-01-01

    The ISIS facility, based at the Rutherford Appleton Laboratory in the UK, is an intense source of neutrons and muons for condensed matter research. The accelerator facility delivers an 800 MeV proton beam of 2.5x1013 protons per pulse at 50 Hz to the present target station. As part of a facility upgrade, it is planned to share the source with a second, 10 Hz, target station. The beam line supplying this target will extract from the existing target station beam line. Electromagnetic Finite Element Modelling techniques have been used to design the magnets required to meet the specified beam line optics. Kicker, septum, dipole, quadrupole, and steering magnets are covered. The magnet design process, involving 2D and 3D modelling, the calculation of ideal shims and chamfers, choice of steel, design of conducting coils, handling of heating issues and eddy current effects, is discussed.

  12. Proton and Pb ion beam extraction experiments with bent crystals at the CERN-SPS

    CERN Document Server

    Elsener, K; Klem, J T; CERN. Geneva. SPS and LEP Division

    1997-01-01

    Extraction of particle beams from the CERN-SPS using bent silicon crystals is described. A summary of the early results is given. Emphasis is on the recent experiments, in particular on the energy dependence of proton extraction at 14, 120 and 270 GeV. 'U-shaped' crystals of different thickness and with a different miscut angle have been compared at 120 GeV. Non-linear excitation of the beam was used in one experiment, with the aim to achieve larger impact parameters - the results show a particular behaviour in the tails of the beam. Finally, the first experimental result on extraction of a 22 TeV fully stripped Pb ion beam with a bent crystal is also described.

  13. Simulation and optimization of beam losses during continuous transfer extraction at the CERN Proton Synchrotron

    CERN Document Server

    Garcia, J B

    2011-01-01

    The proton beams used for the fixed target physics at the Super Proton Synchrotron (SPS) are extracted from the Proton Synchrotron ( PS) by a multiturn technique called continuous transfer (CT). During the CT extraction, large losses are observed in locations where the machine aperture should be large enough to accommodate the circulating beam. This limits the maximum intensity deliverable due to the induced stray radiation outside the PS tunnel. Scattered particles from the interaction with the electrostatic septum are identified as the possible source of these losses. This article presents a detailed study aiming to understand the origin of losses and propose possible cures. The simulations could reproduce accurately the beam loss pattern measured in real machine operation and determine the beam shaving, intrinsic to the extraction process, as the cause for the unexpected losses. Since these losses are unavoidable, the proposed solution implies a new optics scheme displacing the losses to a region with bett...

  14. 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

  15. 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.

  16. 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

  17. 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.

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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)

  3. Construction and 60 kV tests of the prototype pulser for the LHC injection kicker system

    CERN Document Server

    Barnes, M J; Carlier, E; Ducimetière, L; Schröder, G; Vossenberg, Eugène B

    1999-01-01

    The European Laboratory for Particle Physics (CERN) is constructing the Large Hadron Collider (LHC). 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 900 ns rise time and 6.6 mu s flat top duration with a ripple of less than +or-0.5Both injection systems are composed of 4 travelling wave kicker magnets of 2.17 m length each, powered by pulse forming networks (PFNs). To achieve the high-required kick strength of 1.2 Tm, for a compact and cost efficient design, a characteristic impedance of 5 Ohms has been chosen. The design strategy for the magnets and generators has been defined after detailed analysis of existing systems. The electrical circuit has been optimised using the circuit analysis software PSpice. Most known parasitics have been modelled. A prototype PFN has been constructed at CERN and successfully tested at 60 kV. A calibration procedure has been developed and utilised for obtainin...

  4. High efficiency multi-pass proton beam extraction with a bent crystal at the SPS

    Science.gov (United States)

    Altuna, X.; Bussa, M. P.; Carboni, G.; Dehning, B.; Elsener, K.; Ferrari, A.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Klem, J.; Laffin, M.; Lanceri, L.; Mikkelsen, U.; Møller, S. P.; Scandale, W.; Tosello, F.; Uggerhøj, E.; Vuagnin, G.; Weisse, E.; Weisz, S.

    1995-02-01

    Recent measurements of 120 GeV proton extraction by means of a bent silicon crystal at the CERN-SPS accelerator are summarized. The existence of multi-pass extraction has been proven by blocking first-pass extraction: using a crystal covered with an amorphous layer, extracted beam with high efficiency was observed, which provides a direct proof for the importance of the multi-pass mechanism. This opens new possibilities in the design and optimization of a bent crystal extraction scheme.

  5. 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

  6. 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

  7. 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.

  8. 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

  9. Research and development of RHIC injection kicker upgrade with nano second FID pulse generator

    Energy Technology Data Exchange (ETDEWEB)

    Zhang W.; Sandberg, J.; Hahn, H.; Fischer, W.; Liaw, C.J.; Pai, C.; Tuozzolo, J.

    2012-05-20

    Our recent effort to test a 50 kV, 1 kA, 50 ns pulse width, 10 ns pulse rise time FID pulse generator with a 250 ft transmission cable, resistive load, and existing RHIC injection kicker magnet has produced unparalleled results. This is the very first attempt to drive a high strength fast kicker magnet with a nano second high pulsed power (50 MVA) generator for large accelerator and colliders. The technology is impressive. We report here the result and future plan of RHIC Injection kicker upgrade.

  10. 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.

  11. Optimization of cold neutron beam extraction at ESS

    DEFF Research Database (Denmark)

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

    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.......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...

  12. 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

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

    Energy Technology Data Exchange (ETDEWEB)

    Hurst, N. C.; Danielson, J. R.; Surko, C. M., E-mail: csurko@physics.ucsd.edu [Physics Department, University of California, 9500 Gilman Drive, San Diego, La Jolla, California 92093 (United States)

    2015-07-15

    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.

  14. 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

  15. Optimization of the beam extraction systems for the Linac4 H{sup −} ion source

    Energy Technology Data Exchange (ETDEWEB)

    Fink, D. A.; Lettry, J.; Scrivens, R.; Steyaert, D. [CERN, 1211 Geneva 23 (Switzerland); Midttun, Ø. [University of Oslo, P.O. Box 1048, 0316 Oslo (Norway); CERN, 1211 Geneva 23 (Switzerland); Valerio-Lizarraga, C. A. [Departamento de Investigación en Fisica, Universidad de Sonora, Hermosillo (Mexico); CERN, 1211 Geneva 23 (Switzerland)

    2015-04-08

    The development of the Linac 4 and its integration into CERN’s acceleration complex is part of the foreseen luminosity upgrade of the Large Hadron Collider (LHC). The goal is to inject a 160 MeV H{sup −} beam into the CERN PS Booster (PSB) in order to increase the beam brightness by a factor of 2 compared to the 50 MeV proton linac, Linac 2, that is currently in operation. The requirements for the ion source are a 45 keV H{sup −} beam of 80 mA intensity, 2 Hz repetition rate and 0.5 ms pulse length within a normalized rms-emittance of 0.25 mm· mrad. The previously installed beam extraction system has been designed for an H{sup −} ion beam intensity of 20 mA produced by an RF-volume source with an electron to H{sup −} ratio of up to 50. For the required intensity upgrades of the Linac4 ion source, a new beam extraction system is being produced and tested; it is optimized for a cesiated surface RF-source with a nominal beam current of 40 mA and an electron to H{sup −} ratio of 4. The simulations, based on the IBSIMU code, are presented. At the Brookhaven National Laboratory (BNL), a peak beam current of more than 100 mA was demonstrated with a magnetron H{sup −} source at an energy of 35 keV and a repetition rate of 2 Hz. A new extraction system is required to operate at an energy of 45 keV; simulation of a two stage extraction system dedicated to the magnetron is presented.

  16. 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

  17. On the energy dependence of proton beam extraction with a bent crystal

    Science.gov (United States)

    Arduini, G.; Elsener, K.; Fidecaro, G.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Weisse, E.

    1998-03-01

    Proton beam extraction from the CERN SPS by means of a bent silicon crystal is reported at three different energies, 14 GeV, 120 GeV and 270 GeV. The experimental results are compared to computer simulations which contain a sound model of the SPS accelerator as well as the channeling phenomena in bent crystals. The overall energy dependence of crystal assisted proton beam extraction is understood and provides the basis to discuss such a scheme for future accelerators. © 1998

  18. 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.

  19. 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.

  20. 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)

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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)

  7. 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 ...

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. 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

  17. 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

  18. 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.

  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. 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.

  1. 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.

  2. 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

  3. 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

  4. Injection Beam Loss and Beam Quality Checks for the LHC

    CERN Document Server

    Kain, Verena; Bartmann, Wolfgang; Bracco, Chiara; Drosdal, Lene; Holzer, Eva; Khasbulatov, Denis; Magnin, Nicolas; Meddahi, Malika; Nordt, Annika; Sapinski, Mariusz; Vogt, Mathias

    2010-01-01

    The quality of the injection into the LHC is monitored by a dedicated software system which acquires and analyses the pulse waveforms from the injection kickers, and measures key beam parameters and compares them with the nominal ones. The beam losses at injection are monitored on many critical devices in the injection regions, together with the longitudinal filling pattern and maximum trajectory offset on the first 100 turns. The paper describes the injection quality check system and the results from LHC beam commissioning, in particular the beam losses measured during injection at the various aperture limits. The results are extrapolated to full intensity and the consequences are discussed

  5. 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.

  6. Simulations of Full Impact of the LHC Beam With a Solid Graphite Target

    CERN Document Server

    Tahir, N A; Brugger, M; Shutov, A; Lomonosov, I V; Piriz, A R; Hoffmann, D H H

    2009-01-01

    The Large Hadron Collider (LHC) will operate with 7~TeV/c protons with a luminosity of 10$^{34}$ cm$^{-2}$s$^{-1}$. This requires two beams, each with 2808 bunches. The nominal intensity per bunch is 1.15$\\;\\times\\;$10$^{11}$ protons and the total energy stored in each beam is 362 MJ. In previous papers, the mechanisms causing equipment damage in case of a failure of the machine protection system was discussed, assuming that the entire beam is deflected onto a copper target. Another failure scenario is the deflection of beam, or part of it, into carbon material. Carbon collimators and beam absorbers are installed in many locations around the LHC close to the beam, since carbon is the material that is most suitable to absorb the beam energy without being damaged. In case of a failure, it is very likely that such absorbers are hit first, for example, when the beam is accidentally deflected. Some type of failures need to be anticipated, such as accidental firing of injection and extraction kicker magnets leading...

  7. A new concept for the control of a slow-extracted beam in a line with rotational optics: Part II

    CERN Document Server

    Benedikt, Michael; Pullia, M

    1999-01-01

    The current trend in hadrontherapy is towards high-precision, conformal scanning of tumours with a 'pencil' beam of light ions or protons, delivered by a synchrotron using slow extraction. The particular shape of the slow-extracted beam segment in phase space and the need to vary the beam size in a lattice with rotating optical elements create a special problem for the design of the extraction transfer line and gantry. The design concept presented in this report is based on telescope modules with integer-pi phase advances in both transverse planes. The beam size in the plane of the extraction is controlled by altering the phase advance and hence the rotation of the extracted beam segment in phase space. The vertical beam size is controlled by stepping the vertical betatron amplitude function over a range of values and passing the changed beam size from 'hand-to-hand' through the telescope modules to the various treatment rooms. In the example given, a combined phase shifter and 'stepper', at a point close to ...

  8. Study of Slow Beam Extraction Through the Third Order Resonance with Transverse Phase Space Manipulation by a Mono-Frequency RFKO

    CERN Document Server

    Miyamoto, Atsushi; Hinode, Fujio; Kawai, Masayuki; Shinto, Katsuhiro; Tanaka, Takumi

    2005-01-01

    An electron pulse-stretcher ring (STB ring) has a function which converts a pulse beam generated by RF linac into a quasi-continuous beam. Circulating beam in the ring is extracted by the third order resonance. Since there is no accelerating field in the ring, the beam approaches a transverse resonance condition due to synchrotron radiation loss with finite chromaticity. The extracted beam from the ring has some spread in time and space corresponding to injected beam from linac even if the injected beam is perfectly matched to the ring optics. However, the extracted beam emittance can be reduced by applying a phase space manipulation using an RF shaker. Under the influence of perturbation using an RF shaker driven by a mono-frequency, the betatron amplitude of circulating beam can be controlled in order to reduce the extracted beam emittance. The experimental results will be reported in this conference.

  9. 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.

  10. 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.

  11. 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.

  12. 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)

  13. 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.

  14. 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.

  15. 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

  16. 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)

  17. Beam diagnostics, collimation, injection/extraction, targetry, accidents and commissioning: Working group C&G summary report

    Energy Technology Data Exchange (ETDEWEB)

    Mokhov, N.V.; /Fermilab; Hasegawa, K.; /JAEA, Ibaraki; Henderson, S.; /Oak Ridge; Schmidt, R.; /CERN; Tomizawa, M.; /KEK, Tsukuba; Wittenburg, K.; /DESY

    2006-11-01

    The performance of accelerators with high beam power or high stored beam energy is strongly dependent on the way the beam is handled, how beam parameters are measured and how the machine is commissioned. Two corresponding working groups have been organized for the Workshop: group C ''Beam diagnostics, collimation, injection/extraction and targetry'' and group G ''Commissioning strategies and procedures''. It has been realized that the issues to be discussed in these groups are interlaced with the participants involved and interested in the above topics, with an extremely important subject of beam-induced accidents as additional topic. Therefore, we have decided to combine the group sessions as well as this summary report. Status, performance and outstanding issues of each the topic are described in the sections below, with additional observations and proposals by the joint group at the end.

  18. 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.

  19. 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.

  20. 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.

  1. 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

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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 ...

  7. Energy spread and time structure of ion beams extracted from the ReA-EBIT rare isotope charge breeder

    Energy Technology Data Exchange (ETDEWEB)

    Baumann, Thomas M.; Lapierre, Alain; Schwarz, Stefan; Kittimanapun, Kritsada; Bollen, Georg [National Superconducting Cyclotron Laboratory (NSCL), Michigan State University (MSU), 640 S. Shaw Lane, East Lansing, Michigan 48824 (United States)

    2015-01-09

    The ReA re-accelerator of the National Superconducting Cyclotron Laboratory at Michigan State University utilizes an Electron Beam Ion Trap (EBIT) for charge breeding thermalized rare isotope beams. Recent commissioning measurements have been performed to characterize the performance of this EBIT. The energy spread of extracted highly charged ion beams was measured to be about 0.3% of the total beam energy. From this, the temperature of the ion ensemble in the trap is calculated to be kT{sub q}/q = 31eV for O{sup 7+}, while it is kT{sub q}/q = 25eV for K{sup 15+}. In addition initial results are presented for two extraction schemes developed to spread highly charged ion pulses in time.

  8. Design of the beam transport line and injection system of the compact storage ring for TTX

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    In this article, we present the design of the beam transport line and injection system of the compact storage ring for the Tsinghua Thomson scattering X-ray (TTX) source. The layout of the beam transport line fits in with the limited available space. The injection system is simplified, consisting of only one single kicker; the stray field on the reference orbit is also reduced without the septum magnet. We choose a travelling wave kicker and present both 2D and 3D simulations for the structure design.

  9. Extraction of a strongly focusing He+ beam from three-stage concave electrodes for alpha particle measurement system in ITER.

    Science.gov (United States)

    Kobuchi, T; Sasao, M; Kisaki, M; Tsumori, K; Tanaka, N; Okamoto, A; Kitajima, S; Kaneko, O; Shinto, K; Wada, M

    2012-02-01

    A strongly focusing He(+) ion beam source equipped with concave multi-aperture electrodes was developed for production of He(-) through a charge exchange cell. The beam was extracted at a voltage less than 20 kV from 301 apertures distributed in an area of 100 mm φ, and focused at 750 mm distance. The beam current and the beam size of 2 A and 20 mm in diameter, respectively, were achieved with an arc power less than 10 kW. The optimum perveance was obtained at 0.02 A∕kV(1.5) at the beam energy less than 20 keV which is suitable for the conversion to He(-) in an alkali vapor cell.

  10. 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.

  11. 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

  12. 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)

  13. 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.

  14. Radiologic study of the healing process of the extracted socket of beagle dogs using cone beam CT

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Bong Won; Lee, Won; Lee, Byung Do [Department of Oral and Maxillofacial Radiology, School of Dentistry, Wonkwang University, Iksan (Korea, Republic of); Kim, De Sok [Department of Electrical Engineering, Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2009-03-15

    To longitudinally observe the healing process of extracted socket and the alterations of the residual ridge in healthy adult dogs using cone beam CT (CBCT). The mandibular premolars of two beagle dogs were removed and the extraction sites were covered with the gingival tissue. CBCTs (3D X-ray CT scanner, Alphard vega, Asahi Co.) were taken at baseline and at 1 week interval for 12 weeks. Radiographic density of extracted wounds was measured on normalized images with a custom-made image analysis program. The amount of alveolar crestal resorption after the teeth extraction was measured with a reformatted three-dimensional image using CBCT. Bony healing pattern of extracted wound of each group was also longitudinally observed and analyzed. Dimensional changes occurred during the first 6 weeks following the extraction of dogs' mandibular premolars. The reduction of the height of residual ridge was more pronounced at the buccal than at the lingual aspect of the extraction socket. Radiographic density of extracted wounds increased by week 4, but the change in density stabilized after week 6. New bone formation was observed at the floor and the peripheral side of extracted socket from week 1. The entrance of extracted socket was sealed by a hard-tissue bridge at week 5. The healing process of extracted wound involved a series of events including new bone formation and residual ridge resorption.

  15. 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.

  16. 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.

  17. 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

  18. First beam measurements on the vessel for extraction and source plasma analyses (VESPA) at the Rutherford Appleton Laboratory (RAL)

    Energy Technology Data Exchange (ETDEWEB)

    Lawrie, Scott R., E-mail: scott.lawrie@stfc.ac.uk [ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, OX11 0QX (United Kingdom); John Adams Institute for Accelerator Science, Department of Physics, University of Oxford (United Kingdom); Faircloth, Daniel C.; Letchford, Alan P.; Perkins, Mike; Whitehead, Mark O.; Wood, Trevor [ISIS Neutron and Muon Facility, STFC Rutherford Appleton Laboratory, Harwell Oxford, OX11 0QX (United Kingdom)

    2015-04-08

    In order to facilitate the testing of advanced H{sup −} ion sources for the ISIS and Front End Test Stand (FETS) facilities at the Rutherford Appleton Laboratory (RAL), a Vessel for Extraction and Source Plasma Analyses (VESPA) has been constructed. This will perform the first detailed plasma measurements on the ISIS Penning-type H{sup −} ion source using emission spectroscopic techniques. In addition, the 30-year-old extraction optics are re-designed from the ground up in order to fully transport the beam. Using multiple beam and plasma diagnostics devices, the ultimate aim is improve H{sup −} production efficiency and subsequent transport for either long-term ISIS user operations or high power FETS requirements. The VESPA will also accommodate and test a new scaled-up Penning H{sup −} source design. This paper details the VESPA design, construction and commissioning, as well as initial beam and spectroscopy results.

  19. The CERN PS multi-turn extraction based on beam splittting in stable islands of transverse phase space Design Report

    CERN Document Server

    Barnes, M J; Berrig, O E; Beuret, A; Borburgh, J; Bourquin, P; Brown, R; Burnet, Jean Paul; Caspers, Friedhelm; Cravero, J M; Dobers, T; Fowler, T; Gilardoni, S S; Hourican, M; Kalbreier, Willi; Kroyer, T; Di Maio, F; Martini, M; Mertens, V; Métral, E; Metzmacher, K D; Rossi, C; Royer, J P; Sermeus, L; Steerenberg, R; Villiger, G; Zickler, T

    2006-01-01

    Since 2001 considerable effort has been devoted to the study of a possible replacement of the continuous-transfer extraction mode from the PS to the SPS. Such an approach, called Multi-Turn Extraction (MTE), is based on capture of the beam inside stable islands of transverse phase space, generated by sextupoles and octupoles, thanks to a properly chosen tune variation. Both numerical simulations and measurements with beam were performed to understand the properties of this new extraction mode. The experimental study was completed at the end of 2004 and by the end of 2005 a scheme to implement this novel approach in the PS machine was defined and its performance assessed. This design report presents the outcome of the studies undertaken both in terms of technical issues as well as of resources necessary to implement the proposed scheme.

  20. 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

  1. 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

  2. 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.

  3. 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.

  4. 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 C4+ 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 C4+ was almost 14 μA at 15 kV extraction voltage. To get higher current of the C4+ 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 C4+ 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.

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. \\title{MARS15 Simulation Studies in the CMS Detector of Some LHC Beam Accident Scenarios}

    CERN Document Server

    Bhat, Pushpalatha C; Striganov, S.I; Singh, Amandeep

    2009-01-01

    \\begin{abstract} The CMS tracker, made of silicon strips and pixels and silicon-based electronics, is vulnerable to effects of radiation exposure during the LHC operation. Of much concern is the potential for damage from a high instantaneous dose to the pixel detectors and electronics located only a few centimeters from the beam in the event of a fast accidental beam loss. One of the worst case scenarios for such a beam loss is an unintended firing of an abort kicker module, referred to as the kicker pre-fire. MARS15 simulation studies of radiation loads in CMS for the kicker pre-fire scenario are described in this paper. It is found that, in a kicker pre-fire accident, in a time span of about 100 ns, the innermost pixel layer may see a radiation dose of about 0.02 Gy \\-- equivalent to a fluence of $\\sim 6\\times 10^{7}$ MIPs/$cm^2$. No discernible damage to the pixel detectors or the electronics were seen at these levels of fluence in recent beam tests. We note that the dose is about 1000 times smaller t...

  10. 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.

  11. 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.

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

    Science.gov (United States)

    Choi, Jong-il; Kim, Jae-Kyung; Srinivasan, Periasamy; Kim, Jae-Hun; Park, Hyun-Jin; Byun, Myung-Woo; Lee, Ju-Woon

    2009-07-01

    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.

  13. 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.

  14. Upgraded millimeter-wave interferometer for measuring the electron density during the beam extraction in the negative ion source

    Science.gov (United States)

    Tokuzawa, T.; Kisaki, M.; Nagaoka, K.; Tsumori, K.; Ito, Y.; Ikeda, K.; Nakano, H.; Osakabe, M.; Takeiri, Y.; Kaneko, O.

    2016-11-01

    The upgraded millimeter-wave interferometer with the frequency of 70 GHz is installed on a large-scaled negative ion source. Measurable line-averaged electron density is from 2 × 1015 to 3 × 1018 m-3 in front of the plasma grid. Several improvements such as the change to shorter wavelength probing with low noise, the installation of special ordered horn antenna, the signal modulation for a high accuracy digital phase detection, the insertion of insulator, and so on, are carried out for the measurement during the beam extraction by applying high voltage. The line-averaged electron density is successfully measured and it is found that it increases linearly with the arc power and drops suddenly at the beam extraction.

  15. 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...

  16. 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...

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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)

  2. Panofsky magnet for the beam extraction from the synchrotron using a fast Q-magnet and RF-knockout

    Science.gov (United States)

    Masubuchi, S.; Nakanishi, T.

    2011-12-01

    The fast control of the beam spill extracted from a synchrotron is a key function for the spot scanning irradiation in cancer therapy application. The authors propose an extraction method which uses the quadruple field of fast response, as well as the RF-knockout. A Panofsky magnet was developed as a quadruple magnet, with a frequency response of around 10 kHz. The Panofsky magnet has a rectangular beam aperture and plate coils attached to the pole face. A model magnet has been manufactured with ferrite, and static and dynamic magnetic fields were measured. From the measurement we observed that the effects of eddy current in the plate coils were large and the uniformity of the magnetic field gradient in the beam aperture was worse than ±5% with a plate thickness of 0.02 cm and a frequency of current of 10 kHz. For the future, in a detailed design the eddy current effects have to be taken into account.

  3. Panofsky magnet for the beam extraction from the synchrotron using a fast Q-magnet and RF-knockout

    Energy Technology Data Exchange (ETDEWEB)

    Masubuchi, S., E-mail: cisa09016@g.nihon-u.ac.jp [College of Industrial Technology, Nihon University, 1-2-1 Izumicho, Narashino, Chiba 275-8575 (Japan); Nakanishi, T., E-mail: nakanishi.tetsuya@nihon-u.ac.jp [College of Industrial Technology, Nihon University, 1-2-1 Izumicho, Narashino, Chiba 275-8575 (Japan)

    2011-12-15

    The fast control of the beam spill extracted from a synchrotron is a key function for the spot scanning irradiation in cancer therapy application. The authors propose an extraction method which uses the quadruple field of fast response, as well as the RF-knockout. A Panofsky magnet was developed as a quadruple magnet, with a frequency response of around 10 kHz. The Panofsky magnet has a rectangular beam aperture and plate coils attached to the pole face. A model magnet has been manufactured with ferrite, and static and dynamic magnetic fields were measured. From the measurement we observed that the effects of eddy current in the plate coils were large and the uniformity of the magnetic field gradient in the beam aperture was worse than {+-}5% with a plate thickness of 0.02 cm and a frequency of current of 10 kHz. For the future, in a detailed design the eddy current effects have to be taken into account.

  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. 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.

  6. Experiments on the margin of beam induced quenches a superconducting quadrupole magnet in the LHC

    CERN Document Server

    Bracco, C; Bednarek, M J; Nebot Del Busto, E; Goddard, B; Holzer, E B; Nordt, A; Sapinski, M; Schmidt, R; Solfaroli Camillocci, M; Zerlauth, M

    2012-01-01

    Protection of LHC equipment relies on a complex system of collimators to capture injected and circulating beam in case of LHC kicker magnet failures. However, for specific failures of the injection kickers, the beam can graze the injection protection collimators and induce quenches of downstream superconducting magnets. This occurred twice during 2011 operation and cannot be excluded during future operation. Tests were performed during Machine Development periods of the LHC to assess the quench margin of the quadrupole located just downstream of the last injection protection collimator in point 8. In addition to the existing Quench Protection System, a special monitoring instrumentation was installed at this magnet to detect any resistance increase below the quench limit. The correlation between the magnet and Beam Loss Monitor signals was analysed for different beam intensities and magnet currents. The results of the experiments are presented.

  7. Beam Losses in the Extraction Line of a TeV E+ E- Linear Collider With a 20-Mrad Crossing Angle

    Energy Technology Data Exchange (ETDEWEB)

    Ferrari, A.; /Uppsala U.; Nosochkov, Y.; /SLAC

    2006-03-29

    In this paper, we perform a detailed study of the power losses along the postcollision extraction line of a TeV e+e- collider with a crossing angle of 20 mrad between the beams at the interaction point. Five cases are considered here: four luminosity configurations for ILC and one for CLIC. For all of them, the strong beam-beam effects at the interaction point lead to an emittance growth for the outgoing beams, as well as to the production of beamstrahlung photons and e+e- pairs. The power losses along the 20 mrad extraction line, which are due to energy deposition by a fraction of the disrupted beam, of the beamstrahlung photons and of the e+e- coherent pairs, were estimated in the case of ideal collisions, as well as with a vertical position or angular o set at the interaction point.

  8. 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...

  9. 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)

  10. 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.

  11. 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.

  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. 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.

  14. 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

  15. EXTRACT

    DEFF Research Database (Denmark)

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

    2016-01-01

    therefore developed an interactive annotation tool, EXTRACT, which helps curators identify and extract standard-compliant terms for annotation of metagenomic records and other samples. Behind its web-based user interface, the system combines published methods for named entity recognition of environment...... 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/....

  16. 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.

  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. 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.

  19. 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

  20. 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

  1. 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

  2. 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.

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

    Science.gov (United States)

    Tsumori, K.; Ikeda, K.; Nakano, H.; Kisaki, M.; Geng, S.; Wada, M.; Sasaki, K.; Nishiyama, S.; Goto, M.; Serianni, G.; Agostinetti, P.; Sartori, E.; Brombin, M.; Veltri, P.; Wimmer, C.; Nagaoka, K.; Osakabe, M.; Takeiri, Y.; Kaneko, O.

    2016-02-01

    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.

  4. Thermomechanical assessment of the effects of a jaw-beam angle during beam impact on Large Hadron Collider collimators

    Science.gov (United States)

    Cauchi, Marija; Assmann, R. W.; Bertarelli, A.; Carra, F.; Lari, L.; Rossi, A.; Mollicone, P.; Sammut, N.

    2015-02-01

    The correct functioning of a collimation system is crucial to safely and successfully operate high-energy particle accelerators, such as the Large Hadron Collider (LHC). However, the requirements to handle high-intensity beams can be demanding, and accident scenarios must be well studied in order to assess if the collimator design is robust against possible error scenarios. One of the catastrophic, though not very probable, accident scenarios identified within the LHC is an asynchronous beam dump. In this case, one (or more) of the 15 precharged kicker circuits fires out of time with the abort gap, spraying beam pulses onto LHC machine elements before the machine protection system can fire the remaining kicker circuits and bring the beam to the dump. If a proton bunch directly hits a collimator during such an event, severe beam-induced damage such as magnet quenches and other equipment damage might result, with consequent downtime for the machine. This study investigates a number of newly defined jaw error cases, which include angular misalignment errors of the collimator jaw. A numerical finite element method approach is presented in order to precisely evaluate the thermomechanical response of tertiary collimators to beam impact. We identify the most critical and interesting cases, and show that a tilt of the jaw can actually mitigate the effect of an asynchronous dump on the collimators. Relevant collimator damage limits are taken into account, with the aim to identify optimal operational conditions for the LHC.

  5. 一台14GHz CAPRICE型ECR离子源的束流引出%Ion Beam Extracted from a 14GHz ECRIS of CAPRICE Type

    Institute of Scientific and Technical Information of China (English)

    P.Sp(a)dtke; R.Lang; J.M(a)der; J.Roβbach; K.Tinschert; J.Stetson

    2007-01-01

    An ion beam extracted from an ECRIS suffers from the inhomogeneous distribution of cold electrons within the minimum B configuration,necessary to confine the plasma.Especially for higher ion currents,the space charge force is not negligible any more,and because of the nonlinear force,emittance growth will occur.Measurements of the profile and the emittance of the beam directly behind the source show the complicated correlation between extraction voltage and plasma density.The emittance has been measured with a pepper pot device to account for the inhomogeneous azimuthal distribution of the beam.These results indicate that further information about the profile is required.To visualize the beam profile a tantalum foil with a thickness of 20μm has been used for an electrical beam power between 10 and 50W.Looking on the back side of the foil with a CCD camera it is possible to record the profile in real time.As a more sensitive diagnostic tool viewing targets made from BaF has been used.Three dimensional computer simulations have been used to identify the reason for the structures,observed in measurements.

  6. 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.

  7. 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

  8. 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.)

  9. Extraction of radioactive positive ions across the surface of superfluid helium : A new method to produce cold radioactive nuclear beams

    NARCIS (Netherlands)

    Huang, WX; Dendooven, P; Gloos, K; Takahashi, N; Pekola, JP; Aysto, J

    2003-01-01

    Alpha-decay recoils Rn-219 were stopped in superfluid helium and positive ions were extracted by electric field into the vapour phase. This first quantitative observation of extraction was successfully conducted using highly sensitive radioactivity detection. The efficiency for extraction across the

  10. 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.

  11. Conceptual Design of a Beam line for Post-Collision extraction and diagnostics at the multi-TeV Compact Linear Collider

    CERN Document Server

    Ferrari, A; Appleby, R; Salt, M

    2009-01-01

    Strong beam-beam effects at the interaction point of a high-energy e+e- linear collider such as the Compact Linear Collider (CLIC) lead to an emittance growth for the outgoing beams, as well as to the production of beamstrahlung photons and e+e- coherent pairs. In this paper, we present a conceptual design of a 150 m long post-collision extraction line for the CLIC machine at 3 TeV, which separates the various components of the outgoing beam using a vertical magnetic chicane, before transporting them to their respective dump. In addition, detailed studies are performed in order to compute the power losses along the CLIC post-collision line. For the vacuum window at the exit of the post-collision line, we propose a thick (1.5 cm) layer of carbon-carbon composite, with a thin (0.2 mm) aluminum leak-tight foil. The stress levels in this exit window are estimated. Finally, we discuss the use of diagnostics along the post-collision line for monitoring and improving the quality of the e+e- collisions and, in turn, ...

  12. 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.

  13. 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)

  14. 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.

  15. 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.

  16. 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.

  17. Clinical use of cone beam CT in impacted maxillary tooth extraction and artifistulation%锥形束CT定位埋伏牙的临床应用

    Institute of Scientific and Technical Information of China (English)

    董辉; 冯春丽; 孙蕾; 祁森荣; 夏登胜

    2011-01-01

    目的 探讨锥形束CT影像和三维重建技术在辅助埋伏牙拔除和正畸开窗牙牵引术中的作用.方法 选择53颗常规曲面断层片难以确定埋伏牙空间位置的患者进行锥形束CT扫描,其中对5例复杂埋伏牙的CT图像进行三维重建.45例埋伏牙依据CT图像选择不同手术入路行拔牙术,8例埋伏牙采用颌骨开窗牵引术.结果 螺旋CT影像对正确选择埋伏牙拔除的手术入路具有良好的指导作用;CT三维重建图像能清楚地显示埋伏牙的牙体形态、唇腭向位置以及和邻牙的关系,正确指导手术开窗牵引的入路和开窗牵引装置的固定.结论 锥形束CT和三维重建技术在显示埋伏牙的位置和牙体形态上明显优于传统的曲面断层和根尖片.%Objective To evaluate the value of cone beam CT and three-dimensional reconstruction in impacted maxillary tooth extraction and artifistulation. Methods Fifty-three patients with impacted maxillary teeth were included and examined by cone beam CT, and 3D reconstruction was conducted in five of them . Results The cone beam CT images clearly denmonstrated the location of the teeth and provided help in the impacted tooth extraction. The threedimensional reconstruction technique guided and simplified the procedure of artifistulation. Conclusion Cone beam CT has more advantages in assistance of impacted tooth extraction and artifistulation in orthodontics compared with traditional panoramic radiography.

  18. 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.

  19. 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.

  20. 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)

  1. Power combiners/dividers for loop pickup and kicker arrays for FNAL stochastic cooling rings

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, J.K.; Nemetz, R.

    1985-05-01

    The anti-proton accumulator and debuncher at FNAL will use stochastic methods to ''cool'' the beam. Pairs of quarter-wavelength directional-coupler loops are used to detect and kick the beam. The loops are copper plates which are flush with the upper and lower wall of a rectangular beam pipe. The plates, when surrounded by a properly sized pocket, form a 100-ohm transmission-line directional coupler. As the beam passes, a signal which gives position and time information, is induced in the plates. But, because the signal levels are low (<.5 picowatts per pair), a power combiner (usually several primary combiners feeding a secondary combiner) is used to combine the outputs of many loops. Subsequently, the combined signal is amplified, filtered and then fed into a divider, (that is, a combiner operating in reverse). The divider distributes the signal into a different set of loops which modify (kick) the beam's position. Since the loop couplers are arranged linearly, in arrays of various lengths, combiners also provide a convenient method of reducing the number of vacuum feedthroughs and preamplifiers and their related costs in performance and dollars. In this note we describe various stripline combiner systems that add the outputs of 4, 8, 16 or 32 loops.

  2. 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...

  3. 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.

  4. Using a carbon beam as a probe to extract the sensitive volume thickness; Utilisation d'un faisceau de carbon pour extraire le volume sensible

    Energy Technology Data Exchange (ETDEWEB)

    Inguimbert, C.; Duzellier, S. [Office National d' Etudes et de Recherches Aerospatiales (ONERA/DESP), 31 - Toulouse (France); Ecoffet, R. [Centre National d' Etudes Spatiales (CNES), 31 - Toulouse (France)

    1999-07-01

    Most of the models of proton SEUs predictions use the sensitive volume concept. The sensitive region is modeled by a parallelepiped with length l, width w and thickness d, buried at depth h. We propose a new method to extract the sensitive thickness d. The idea is to use low energy, low range ion in order to probe the component to measure the sensitive volume. The thickness d is obtained by de-convoluting the heavy ion upset cross-section curve with the LET (linear energy transfer) curve, both curves being considered as functions of the range of the incident ion. This method has been tested using a beam of carbon ions and the calculated thickness is closed to the theoretical expected value. The deconvolution method which couples together a sensitive thickness d and a charge collection efficiency {alpha} improves the sensitive volume concept.

  5. 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.

  6. 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.

  7. 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...

  8. Method of Extracting Information from Single Beam Forward-Looking Sonar%单波束前视声纳的信息提取方法研究

    Institute of Scientific and Technical Information of China (English)

    杨辉; 李硕; 曾俊宝

    2012-01-01

    介绍了一种可用于小型水下机器人的前视声纳信息提取方法.利用该方法获取了声纳视域内目标的方位信息,这在小型水下机器人的自主目标跟踪和避碰方面具有很大的应用价值.该方法主要包括3个部分的内容:利用声纳数据生成声纳图像;对声纳图像进行预处理;从处理后的图像中提取目标的特征信息.针对图像中较大目标的边缘信息,提出了一种基于最小二乘法的分段曲线拟合的方法,并给出了基于实验室的水池中获得的实测数据的拟合结果,验证了该方法的有效性.%A method of extracting information from raw sonar scanline data generated by a single-beam FLS mounted on a small UUV (unmanned underwater vehicle) is described. The bearing and distance information has been acquired through this method and this result could be highly used in the problems of auto-tracking and obstacle detection and avoidance. This procedure includes generating sonar image by raw sonar scanline data, processing the raw sonar image and extracting feature information of objects detected in the processed image . Aiming at extracting the edge feature information of a large object, a segmented curve fitting method is proposed based on least squares theory and the effectiveness of the method is verified by the experiment of processing the actual data acquired from the laboratory pool.

  9. 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

  10. 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...

  11. Design of Phase Feed Forward System in CTF3 and Performance of Fast Beam Phase Monitors

    CERN Document Server

    Skowronski, P K; Ghigo, A; Marcellini, F; Burrows, PN; Christian, GB; Perry, C; Gerbershagen, A; Roberts, J; Ikarios, E

    2013-01-01

    The CLIC two beam acceleration technology requires a drive beam phase stability better than 0.3 deg rms at 12 GHz, corresponding to a timing stability below 50 fs rms. For this reason the CLIC design includes a phase stabilization feed-forward system. It relies on precise beam phase measurements and their subsequent correction in a chicane with the help of fast kickers. A prototype of such a system is being installed in the CLIC Test Facility CTF3. In this paper its design and implementation is described in detail. Additionally, the performance of the precision phase monitor prototypes installed at the end of the CTF3 linac, as measured with the drive beam, is presented.

  12. 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

  13. 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

  14. Advanced module for model parameter extraction using global optimization and sensitivity analysis for electron beam proximity effect correction

    Science.gov (United States)

    Figueiro, Thiago; Choi, Kang-Hoon; Gutsch, Manuela; Freitag, Martin; Hohle, Christoph; Tortai, Jean-Hervé; Saib, Mohamed; Schiavone, Patrick

    2012-11-01

    In electron proximity effect correction (PEC), the quality of a correction is highly dependent on the quality of the model. Therefore it is of primary importance to have a reliable methodology to extract the parameters and assess the quality of a model. Among others the model describes how the energy of the electrons spreads out in the target material (via the Point Spread Function, PSF) as well as the influence of the resist process. There are different models available in previous studies, as well as several different approaches to obtain the appropriate value for their parameters. However, those are restricted in terms of complexity, or require a prohibitive number of measurements, which is limited for a certain PSF model. In this work, we propose a straightforward approach to obtain the value of parameters of a PSF. The methodology is general enough to apply for more sophisticated models as well. It focused on improving the three steps of model calibration procedure: First, it is using a good set of calibration patterns. Secondly, it secures the optimization step and avoids falling into a local optimum. And finally the developed method provides an improved analysis of the calibration step, which allows quantifying the quality of the model as well as enabling a comparison of different models. The methodology described in the paper is implemented as specific module in a commercial tool.

  15. 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.

  16. 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...

  17. Installation and Hardware commissioning of the Multi-Turn extraction at the CERN proton synchrotron

    CERN Document Server

    Gilardoni, S; Barnes, M; Berrig, O; Beuret, A; Bodart, D; Bourquin, P; Brown, R; Caccioppoli, M; Caspers, Friedhelm; Cravero, JM; De Almeida Martins, C; Dehavay, C; Dobers, T; Dupont, M; Favre, G; Fowler, T; Franchi, A; Giovannozzi, M; Hansen, J; Karppinen, M; Lacroix, C; Mahner, E; Mertens, V; Monteiro, JL; Noulibos, R; Page, E; Principe, R; Rossi, C; Sermeus, L; Steerenberg, R; Vandoni, G; Villiger, G; Zickler, T

    2010-01-01

    The implementation of the new Multi-Turn Extraction (MTE) at the CERN Proton Synchrotron required major hardware changes for the nearly 50-year old accelerator. The installation of new Pulse Forming Networks (PFN) and refurbished kicker magnets for the extraction, new sextupole and octupole magnets, new power converters, together with an in-depth review of the machine aperture leading to the design of new vacuum chambers was required. As a result, a heavy programme of interventions had to be scheduled during the winter shut-down 2007-8. The newly installed hardware and its commissioning is presented and discussed in details.

  18. 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.

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

    Science.gov (United States)

    Nelson, Jovan; Bhat, Chandrashekhara; Hendricks, Brian

    2016-03-01

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

  20. 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.

  1. LS1 Report: alive and kicking!

    CERN Document Server

    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...

  2. 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...

  3. 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.

  4. 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.)

  5. 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

  6. 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.

  7. 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.

  8. 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)

  9. 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.

  10. 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.

  11. 锥形束CT在埋伏牙拔除中的临床应用%Clinical use of cone beam CT in extraction of impacted tooth

    Institute of Scientific and Technical Information of China (English)

    陈井鑫; 邓伟; 王鸿; 符良斌; 甘成文

    2012-01-01

    目的:评价锥形束CT (CBCT)在颌骨埋伏牙诊断和治疗中的临床价值.方法:对常规口腔全景片和咬合片不能清楚定位的埋伏牙20例患者进行锥形束CT扫描获得高分辨率影像,并使用专用软件“i-View”进行任意断面的观察.结果:本组共23颗埋伏牙被精确定位,并根据“i-View”软件分析最佳手术入路后均顺利拔除埋伏牙.结论:锥形束CT是检查埋伏牙准确有效的方法,在埋伏牙拔除的方案制定中有重要的指导价值.%Objective To investigate the value of diagnosisand treatment of the impacted teeth in jaw bones by Cone-beam CT. Methods Cone-beam CT was applied to localize impacted teeth in jaw bones in 20 cases that can not be localized exactly by Oral panoramic and occlusal film.And we observeany section by"i-View"software. Results Cone-beam CT was applied tolocalizeexactly in 23 cases of impacted teeth in jaw bones. The impacted teeth in jaw bones were successfully removed. Conclusion Cone-beam CT is aneffective method to check impacted teeth. Cone-beam CT has an important guiding valuein removing impacted teeth.

  12. 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.

  13. 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.

  14. 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...

  15. 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

  16. Resolving two beams in beam splitters with a beam position monitor

    Energy Technology Data Exchange (ETDEWEB)

    Kurennoy, S. (Sergey)

    2002-01-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters. Monitoring two separated beams in a common beam pipe in the splitter sections imposes certain requirements on diagnostics for these sections. In this note we explore a two-beam system in a generic beam monitor and study the feasibility of resolving the positions of the two beams with a single diagnostic device. In the Advanced Hydrotest Facility (AHF), 20-ns beam pulses (bunches) are extracted from the 50-GeV main proton synchrotron and then are transported to the target by an elaborated transport system. The beam transport system splits the beam bunches into equal parts in its splitting sections so that up to 12 synchronous beam pulses can be delivered to the target for the multi-axis proton radiography. Information about the transverse positions of the beams in the splitters, and possibly the bunch longitudinal profile, should be delivered by some diagnostic devices. Possible candidates are the circular wall current monitors in the circular pipes connecting the splitter elements, or the conventional stripline BPMs. In any case, we need some estimates on how well the transverse positions of the two beams can be resolved by these monitors.

  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. 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)

  19. 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

  20. A beam source model for scanned proton beams

    Science.gov (United States)

    Kimstrand, Peter; Traneus, Erik; Ahnesjö, Anders; Grusell, Erik; Glimelius, Bengt; Tilly, Nina

    2007-06-01

    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.

  1. 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)

  2. 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...

  3. 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.

  4. 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.

  5. Cold and Slow Molecular Beam

    CERN Document Server

    Lu, Hsin-I; Wright, Matthew J; Patterson, Dave; 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. One modestly boosted beam has a forward velocity of vf = 65 m/s, a narrow velocity spread, and a flux of 10^9 molecules per pulse. The other has the slowest forward velocity of vf = 40 m/s, a longitudinal temperature of 3.6 K, and a flux of 5x10^8 molecules per pulse.

  6. 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)

  7. ALCBEAM - Neutral beam formation and propagation code for beam-based plasma diagnostics

    Science.gov (United States)

    Bespamyatnov, I. O.; Rowan, W. L.; Liao, K. T.

    2012-03-01

    ALCBEAM is a new three-dimensional neutral beam formation and propagation code. It was developed to support the beam-based diagnostics installed on the Alcator C-Mod tokamak. The purpose of the code is to provide reliable estimates of the local beam equilibrium parameters: such as beam energy fractions, density profiles and excitation populations. The code effectively unifies the ion beam formation, extraction and neutralization processes with beam attenuation and excitation in plasma and neutral gas and beam stopping by the beam apertures. This paper describes the physical processes interpreted and utilized by the code, along with exploited computational methods. The description is concluded by an example simulation of beam penetration into plasma of Alcator C-Mod. The code is successfully being used in Alcator C-Mod tokamak and expected to be valuable in the support of beam-based diagnostics in most other tokamak environments. Program summaryProgram title: ALCBEAM Catalogue identifier: AEKU_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEKU_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 66 459 No. of bytes in distributed program, including test data, etc.: 7 841 051 Distribution format: tar.gz Programming language: IDL Computer: Workstation, PC Operating system: Linux RAM: 1 GB Classification: 19.2 Nature of problem: Neutral beams are commonly used to heat and/or diagnose high-temperature magnetically-confined laboratory plasmas. An accurate neutral beam characterization is required for beam-based measurements of plasma properties. Beam parameters such as density distribution, energy composition, and atomic excited populations of the beam atoms need to be known. Solution method: A neutral beam is initially formed as an ion beam which is extracted from

  8. 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.

  9. 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.)

  10. Beam collimator

    CERN Multimedia

    1977-01-01

    A four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with SPS secondary beams, the collimator operates under vacuum conditions. See Annual Report 1976 p. 121 and photo 7701014.

  11. Beam Interlocks for LHC and SPS

    CERN Document Server

    Dinius, A; Gimeno-Vicente, J; Nouchi, P; Puccio, B; Schmidt, R; Wenninger, J

    2003-01-01

    The Large Hadron Collider at CERN (LHC) will operate at 7 TeV/c with a luminosity of 10 cms. This requires two beams with about 3^10 protons/beam, corresponding to a stored energy of about 350 MJ, sufficient to heat and melt 500 kg of copper. Protection of equipment from damage in case of uncontrolled beam losses is challenging. Injection of the beam from the SPS to the LHC could already damage equipment and is only permitted when all LHC systems are correctly prepared. In case of an uncontrolled loss of the circulating LHC beams, it is required to extract the beams into a specially designed target as soon as possible. Beam loss monitors and equipment for hardware surveillance are distributed around the 26 km long accelerator. In case of failures or beam losses, the beam interlock system is informed and sends a dump request to the beam dumping system. The beam interlock system also inhibits injection when the LHC is not ready for beam. In this paper the requirements for the beam interlock system are discussed...

  12. The ELENA Beam Diagnostics Systems

    CERN Document Server

    Tranquille, G

    2013-01-01

    The Extra Low ENergy Antiproton ring (ELENA) to be built at CERN is aimed at substantially increasing the number of antiprotons to the low energy antiproton physics community. It will be a small machine which will decelerate low intensity beams (<4x107) from 5.3 MeV to 100 keV and will be equipped with an electron cooler to avoid beam losses during the deceleration and to significantly reduce beam phase space at extraction. To measure the beam parameters from the extraction point of the Antiproton Decelerator (AD), through the ELENA ring and all the way to the experiments, many systems will be needed to ensure that the desired beam characteristics are obtained. Particular attention needs to be paid to the performance of the electron cooler which depends on reliable instrumentation in order to efficiently cool the antiprotons. This contribution will present the different monitors that have been proposed to measure the various beam parameters as well as some of the developments going on to further improve th...

  13. 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

  14. 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)

  15. 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.

  16. 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

  17. 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.

  18. 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)

  19. Resolution studies with the DATURA beam telescope

    CERN Document Server

    Jansen, Hendrik

    2016-01-01

    We present resolution studies carried out with the DATURA beam telescope, which belongs to the family of EUDET-type beam telescopes. The EUDET-type beam telescopes make use of CMOS MIMOSA 26 pixel detectors for particle tracking allowing for precise characterisation of particle sensing devices. A profound understanding of the performance of the beam telescope as a whole is obtained by a detailed characterisation of the sensors themselves. We extract the differential intrinsic resolution as measured in a MIMOSA 26 sensor using an iterative pull method and show various clustersize dependent quantities as the residual distribution, the intra-pixel residual width distribution and the intra-pixel frequency distribution.

  20. 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

  1. 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 ...

  2. 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

  3. 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.

  4. 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

  5. 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)

  6. 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.

  7. 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

  8. 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

  9. 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.

  10. 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)

  11. Stable beams

    CERN Multimedia

    2015-01-01

    Stable beams: two simple words that carry so much meaning at CERN. When LHC page one switched from "squeeze" to "stable beams" at 10.40 a.m. on Wednesday, 3 June, it triggered scenes of jubilation in control rooms around the CERN sites, as the LHC experiments started to record physics data for the first time in 27 months. This is what CERN is here for, and it’s great to be back in business after such a long period of preparation for the next stage in the LHC adventure.   I’ve said it before, but I’ll say it again. This was a great achievement, and testimony to the hard and dedicated work of so many people in the global CERN community. I could start to list the teams that have contributed, but that would be a mistake. Instead, I’d simply like to say that an achievement as impressive as running the LHC – a machine of superlatives in every respect – takes the combined effort and enthusiasm of everyone ...

  12. 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. THE LINAC LASER NOTCHER FOR THE FERMILAB BOOSTER

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, David E, [Fermilab; Duel, Kevin [Fermilab; Gardner, Matthew [Fermilab; Johnson, Todd [Fermilab; Slimmer, David [Fermilab; Patil, Screenvias [PriTel, Inc; Tafoya, Jason [Optical Engines, Inc

    2016-09-27

    In synchrotron machines, the beam extraction is accomplished by a combination of septa and kicker magnets which deflect the beam from an accelerator into another. Ideally the kicker field must rise/fall in between the beam bunches. However, in reality, an intentional beam-free time region (aka "notch") is created on the beam pulse to assure that the beam can be extracted with minimal losses. In the case of the Fermilab Booster, the notch is created in the ring near injection energy by the use of fast kickers which deposit the beam in a shielded collimation region within the accelerator tunnel. With increasing beam power it is desirable to create this notch at the lowest possible energy to minimize activation. The Fermilab Proton Improvement Plan (PIP) initiated an R&D project to build a laser system to create the notch within a linac beam pulse at 750 keV. This talk will describe the concept for the laser notcher and discuss our current status, commissioning results, and future plans.

  14. 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...

  15. 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.

  16. 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.

  17. 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.)

  18. Beam-beam effects in the Tevatron

    Energy Technology Data Exchange (ETDEWEB)

    Shiltsev, V.; Alexahin, Y.; Lebedev, V.; Lebrun, P.; Moore, R.S.; Sen, T.; Tollestrup, A.; Valishev, A.; Zhang, X.L.; /Fermilab

    2005-01-01

    The Tevatron in Collider Run II (2001-present) is operating with 6 times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Electromagnetic long-range and head-on interactions of high intensity proton and antiproton beams have been significant sources of beam loss and lifetime limitations. We present observations of the beam-beam phenomena in the Tevatron and results of relevant beam studies. We analyze the data and various methods employed in operations, predict the performance for planned luminosity upgrades, and discuss ways to improve it.

  19. Scattering of singular beams by subwavelength objects

    CERN Document Server

    Hemo, Evyatar; Shamir, Joseph

    2013-01-01

    In recent years, there has been a mounting interest in better methods of measuring nanoscale objects, especially in fields such as nanotechnology, biomedicine, cleantech, and microelectronics. Conventional methods have proved insufficient, due to the classical diffraction limit or slow and complicated measuring procedures. The purpose of this paper is to explore the special characteristics of singular beams with respect to the investigation of subwavelength objects. Singular beams are light beams that contain one or more singularities in their physical parameters, such as phase or polarization. We focus on the three-dimensional interaction between electromagnetic waves and subwavelength objects to extract information about the object from the scattered light patterns.

  20. Beam halo in high-intensity beams

    International Nuclear Information System (INIS)

    In space-charge dominated beams the nonlinear space-charge forces produce a filamentation pattern, which in projection to the 2-D phase spaces results in a 2-component beam consisting of an inner core and a diffuse outer halo. The beam-halo is of concern for a next generation of cw, high-power proton linacs that could be applied to intense neutron generators for nuclear materials processing. The author describes what has been learned about beam halo and the evolution of space-charge dominated beams using numerical simulations of initial laminar beams in uniform linear focusing channels. Initial results are presented from a study of beam entropy for an intense space-charge dominated beam

  1. ACCELERATOR SYSTEMS MODIFICATIONS FOR A SECOND TARGET STATION AT THE OAK RIDGE SPALLATION NEUTRON SOURCE

    Energy Technology Data Exchange (ETDEWEB)

    Galambos, John D [ORNL; Kim, Sang-Ho [ORNL; Plum, Michael A [ORNL

    2014-01-01

    A second target station is planned for the Oak Ridge Spallation Neutron Source. The ion source will be upgraded to increase the peak current from 38 to 49 mA, additional superconducting RF cavities will be added to the linac to increase the H beam energy from 938 to 1300 MeV, and the accumulator ring will receive modifications to the injection and extraction systems to accommodate the higher beam energy. After pulse compression in the storage ring one sixth of the beam pulses (10 out of 60 Hz) will be diverted to the second target by kicker and septum magnets added to the existing Ring to Target Beam Transport (RTBT) line. No further modifications will be made to the RTBT so that when the kicker and septum magnets are turned off the original beam transport lattice will be unaffected. In this paper we will discuss these and other planned modifications and upgrades to the accelerator facility.

  2. Beam imaging sensor

    Energy Technology Data Exchange (ETDEWEB)

    McAninch, Michael D.; Root, Jeffrey J.

    2016-07-05

    The present invention relates generally to the field of sensors for beam imaging and, in particular, to a new and useful beam imaging sensor for use in determining, for example, the power density distribution of a beam including, but not limited to, an electron beam or an ion beam. In one embodiment, the beam imaging sensor of the present invention comprises, among other items, a circumferential slit that is either circular, elliptical or polygonal in nature.

  3. 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)

  4. 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.)

  5. 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

  6. High intensity proton beam transportation through fringe field of 70 MeV compact cyclotron to beam line targets

    Science.gov (United States)

    Zhang, Xu; Li, Ming; Wei, Sumin; Xing, Jiansheng; Hu, Yueming; Johnson, Richard R.; Piazza, Leandro; Ryjkov, Vladimir

    2016-06-01

    From the stripping points, the high intensity proton beam of a compact cyclotron travels through the fringe field area of the machine to the combination magnet. Starting from there the beams with various energy is transferred to the switching magnet for distribution to the beam line targets. In the design of the extraction and transport system for the compact proton cyclotron facilities, such as the 70 MeV in France and the 100 MeV in China, the space charge effect as the beam crosses the fringe field has not been previously considered; neither has the impact on transverse beam envelope coupled from the longitudinal direction. Those have been concerned much more with the higher beam-power because of the beam loss problem. In this paper, based on the mapping data of 70 MeV cyclotron including the fringe field by BEST Cyclotron Inc (BEST) and combination magnet field by China Institute of Atomic Energy (CIAE), the beam extraction and transport are investigated for the 70 MeV cyclotron used on the SPES project at Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro (INFN-LNL). The study includes the space charge effect and longitudinal and transverse coupling mentioned above, as well as the matching of beam optics using the beam line for medical isotope production as an example. In addition, the designs of the ±45° switching magnets and the 60° bending magnet for the extracted beam with the energy from 35 MeV to 70 MeV have been made. Parts of the construction and field measurements of those magnets have been done as well. The current result shows that, the design considers the complexity of the compact cyclotron extraction area and fits the requirements of the extraction and transport for high intensity proton beam, especially at mA intensity levels.

  7. Micro computer aided beam transport for the SF cyclotron

    International Nuclear Information System (INIS)

    An improvement of the beam transport system for the SF cyclotron is described. The system was designed to handle on-line alignment of the beam extracted from the SF cyclotron onto the optical axis of the transport line. It also enables to measure the beam emittance. The measurement of the emittance parameters is in particular necessary to calculate the beam optics. The calculation has been modified to become easy to handle. With the help of the computer-aided on-line beam profile measurement system, the operation of the beam transport system is very subservient to shorten the beam-tuning time and to improve the beam-transmission efficiency and the quality. (author)

  8. Beam dynamics design of the Compact Linear Collider Drive Beam injector

    Energy Technology Data Exchange (ETDEWEB)

    Hajari, Sh. Sanaye, E-mail: ssanayeh@cern.ch [Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); European Organization for Nuclear Research (CERN), BE Department, CH-1211 Geneva 23 (Switzerland); Shaker, H. [Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, P.O. Box 19395-5531, Tehran (Iran, Islamic Republic of); European Organization for Nuclear Research (CERN), BE Department, CH-1211 Geneva 23 (Switzerland); Doebert, S. [European Organization for Nuclear Research (CERN), BE Department, CH-1211 Geneva 23 (Switzerland)

    2015-11-01

    In the Compact Linear Collider (CLIC) the RF power for the acceleration of the Main Beam is extracted from a high-current Drive Beam that runs parallel to the main linac. The longitudinal and transverse beam dynamics of the Drive Beam injector has been studied in detail and optimized. The injector consists of a thermionic gun followed by a bunching system, some accelerating structures, and a magnetic chicane. The bunching system contains three sub-harmonic bunchers, a prebuncher, and a traveling wave buncher all embedded in a solenoidal magnetic field. The main characteristic of the Drive Beam injector is the phase coding process done by the sub-harmonic bunching system operating at half the acceleration frequency. This process is essential for the frequency multiplication of the Drive Beam. During the phase coding process the unwanted satellite bunches are produced that adversely affects the machine power efficiency. The main challenge is to reduce the population of particles in the satellite bunches in the presence of strong space-charge forces due to the high beam current. The simulation of the beam dynamics has been carried out with PARMELA with the goal of optimizing the injector performance compared to the existing model studied for the Conceptual Design Report (CDR). The emphasis of the optimization was on decreasing the satellite population, the beam loss in the magnetic chicane and limiting the beam emittance growth in transverse plane.

  9. A symplectic coherent beam-beam model

    International Nuclear Information System (INIS)

    We consider a simple one-dimensional model to study the effects of the beam-beam force on the coherent dynamics of colliding beams. The key ingredient is a linearized beam-beam kick. We study only the quadrupole modes, with the dynamical variables being the 2nd-order moments of the canonical variables q, p. Our model is self-consistent in the sense that no higher order moments are generated by the linearized beam-beam kicks, and that the only source of violation of symplecticity is the radiation. We discuss the round beam case only, in which vertical and horizontal quantities are assumed to be equal (though they may be different in the two beams). Depending on the values of the tune and beam intensity, we observe steady states in which otherwise identical bunches have sizes that are equal, or unequal, or periodic, or behave chaotically from turn to turn. Possible implications of luminosity saturation with increasing beam intensity are discussed. Finally, we present some preliminary applications to an asymmetric collider. 8 refs., 8 figs

  10. Literature in Focus Beta Beams: Neutrino Beams

    CERN Multimedia

    2009-01-01

    By Mats Lindroos (CERN) and Mauro Mezzetto (INFN Padova, Italy) Imperial Press, 2009 The beta-beam concept for the generation of electron neutrino beams was first proposed by Piero Zucchelli in 2002. The idea created quite a stir, challenging the idea that intense neutrino beams only could be produced from the decay of pions or muons in classical neutrino beams facilities or in future neutrino factories. The concept initially struggled to make an impact but the hard work by many machine physicists, phenomenologists and theoreticians over the last five years has won the beta-beam a well-earned position as one of the frontrunners for a possible future world laboratory for high intensity neutrino oscillation physics. This is the first complete monograph on the beta-beam concept. The book describes both technical aspects and experimental aspects of the beta-beam, providing students and scientists with an insight into the possibilities o...

  11. Telecommunication using muon beams

    Science.gov (United States)

    Arnold, Richard C.

    1976-01-01

    Telecommunication is effected by generating a beam of mu mesons or muons, varying a property of the beam at a modulating rate to generate a modulated beam of muons, and detecting the information in the modulated beam at a remote location.

  12. CTF3 Drive Beam Injector Optimisation

    CERN Document Server

    AUTHOR|(CDS)2082899; Doebert, S

    2015-01-01

    In the Compact Linear Collider (CLIC) the RF power for the acceleration of the Main Beam is extracted from a high-current Drive Beam that runs parallel to the main linac. The main feasibility issues of the two-beam acceleration scheme are being demonstrated at CLIC Test Facility 3 (CTF3). The CTF3 Drive Beam injector consists of a thermionic gun followed by the bunching system and two accelerating structures all embedded in solenoidal magnetic field and a magnetic chicane. Three sub-harmonic bunchers (SHB), a prebuncher and a travelling wave buncher constitute the bunching system. The phase coding process done by the sub-harmonic bunching system produces unwanted satellite bunches between the successive main bunches. The beam dynamics of the CTF3 Drive Beam injector is reoptimised with the goal of improving the injector performance and in particular decreasing the satellite population, the beam loss in the magnetic chicane and the beam emittance in transverse plane compare to the original model based on P. Ur...

  13. Cryogenic Beam Loss Monitoring for the LHC

    CERN Document Server

    Kurfuerst, C; Sapinski, M

    A Beam Loss Monitoring (BLM) system was installed on the outside surface of the LHC magnet cryostats to protect the accelerator equipment from beam losses. The protection is achieved by extracting the beam from the ring in case thresholds imposed on measured radiation levels are exceeded. Close to the interaction regions of the LHC, the present BLM system is sensitive to particle showers generated in the interaction region of the two beams. In the future, with beams of higher energy and brightness resulting in higher luminosity, distinguishing between these interaction products and possible quench-provoking beam losses from the primary proton beams will be challenging. The particle showers measured by the present BLM configuration are partly shielded by the cryostat and the iron yoke of the magnets. The system can hence be optimised by locating beam loss monitors as close as possible to the protected element, i. e. the superconducting coils, inside the cold mass of the magnets in superfluid helium at 1.9 K. T...

  14. 10 MeV Medical Cyclotron Prototype Beam Commissioning

    Institute of Scientific and Technical Information of China (English)

    GUAN; Feng-ping; GE; Tao; YIN; Zhi-guo; SONG; Guo-fang; ZHANG; Tian-jue; JI; Bin; LI; Peng-zhan; CAO; Lei; HOU; Shi-gang; LIU; Geng-shou; WANG; Feng; LEI; Yu; WU; Long-cheng; WEN; Li-peng; LI; Zhen-guo; CUI; Tao; JIA; Xian-lu; YAO; Hong-juan; PAN; Gao-feng; ZHANG; Su-ping; CAI; Hong-ru; XIE; Huai-dong

    2012-01-01

    <正>A 10 MeV medical cyclotron prototype for the production of short-lived isotopes has been developed independently at CIAE with a time span of 2 years. On the inner target, 8 hours stability test has been finished. The extraction beam is 10 MeV with a beam intensity of 100 μA.

  15. 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

  16. Reconstruction of negative hydrogen ion beam properties from beamline diagnostics

    Energy Technology Data Exchange (ETDEWEB)

    Ruf, Benjamin

    2014-09-25

    For the experimental fusion reactor ITER, which should show the feasibility of sustaining a fusion plasma with a positive power balance, some technology still has to be developed, amongst others also the plasma heating system. One heating technique is the neutral beam injection (NBI). A beam of fast deuterium atoms is injected into the fusion plasma. By heavy particle collisions the beam particles give their energy to the plasma. A NBI system consists of three major components. First, deuterium ions are generated in a low temperature, low pressure plasma of an ion source. At ITER, the requirements on the beam energy of 1 MeV cause the necessity of negative charged deuterium ions. Secondly, the ions are accelerated within an acceleration system with several grids, where the plasma grid is the first grid. The grids are on different descending high voltage potentials. The source itself is on the highest negative potential. Thirdly, the fast deuterium ions have to be neutralised. This thesis deals with the second step in the mentioned beam system, the ion acceleration and beam formation. The underlying experiments and measurements were carried out at the testbeds BATMAN (BAvarianTest MAchine for Negative ions) and ELISE (Extraction from a Large Ion Source Experiment) at the Max-Planck-Institut fuer Plasmaphysik Garching (IPP Garching). The main goal of this thesis is to provide a tool which allows the determination of the beam properties. These are beam divergence, stripping losses and beam inhomogeneity. For this purpose a particle trajectory code has been developed from scratch, namely BBC-NI (Bavarian Beam Code for Negative Ions). The code is able to simulate the whole beam and the outcome of several beam diagnostic tools. The data obtained from the code together with the measurements of the beam diagnostic tools should allow the reconstruction of the beam properties. The major beam diagnostic tool, which is used in this thesis, is the beam emission spectroscopy

  17. Parabolic scaling beams.

    Science.gov (United States)

    Gao, Nan; Xie, Changqing

    2014-06-15

    We generalize the concept of diffraction free beams to parabolic scaling beams (PSBs), whose normalized intensity scales parabolically during propagation. These beams are nondiffracting in the circular parabolic coordinate systems, and all the diffraction free beams of Durnin's type have counterparts as PSBs. Parabolic scaling Bessel beams with Gaussian apodization are investigated in detail, their nonparaxial extrapolations are derived, and experimental results agree well with theoretical predictions.

  18. Ion beam diagnosis

    International Nuclear Information System (INIS)

    This report is an introduction to ion beam diagnosis. After a short description of the most important ion beam parameters measurements of the beam current by means of Faraday cups, calorimetry, and beam current transformers and measurements of the beam profile by means of viewing screens, profile grids and scanning devices, and residual gas ionization monitors are described. Finally measurements in the transverse and longitudinal phase space are considered. (HSI)

  19. Beam induced heating

    CERN Document Server

    Salvant, B; Arduini, G; Assmann, R; Baglin, V; Barnes, M J; Baudrenghien, P; Bracco, C; Bruce, R; Bertarelli, A; Carra, F; Cattenoz, G; Caspers, F; Claudet, S; Day, H; Esteban Mueller, J; Gentini, L; Goddar, B; Grudiev, A; Henrist, B; Jones, R; Lanza, G; Lari, L; Mastoridis, T; Métral, E; Mounet, N; Nougaret, J L; Piguiet, A M; Redaelli, S; Roncarolo, F; Rumolo, G; Sapinski, M; Shaposhinkova, E; Tavian, L; Timmins, M; Uythoven, J; Vidal, A; Wollmann, D

    2012-01-01

    In 2011, the rapid increase of the luminosity performance of LHC came at the expense of increased temperature and pressure readings on several near-beam LHC equipments. In some cases, this beam induced heating was suspected to cause beam dumps and even degradation of the equipment. This contribution aims at gathering the observations of beam induced heating due to beam coupling impedance, their current level of understanding and possible actions that could be implemented during the winter stop 2011-2012.

  20. Section of CMS Beam Pipe Removed

    CERN Multimedia

    2013-01-01

    Seven components of the beam pipe located at the heart of the CMS detector were removed in recent weeks. The delicate operations were performed in several stages as the detector was opened. Video of the extraction of one section: http://youtu.be/arGuFgWM7u0

  1. The ATLAS Diamond Beam Monitor

    CERN Document Server

    Schaefer, Douglas; The ATLAS collaboration

    2015-01-01

    After the first three years of the LHC running the ATLAS experiment extracted it's pixel detector system to refurbish and re-position the optical readout drivers and install a new barrel layer of pixels. The experiment has also taken advantage of this access to also install a set of beam monitoring telescopes with pixel sensors, four each in the forward and backward regions. These telescopes were assembled based on chemical vapour deposited (CVD) diamond sensors to survive in this high radiation environment without needing extensive cooling. This talk will describe the lessons learned in construction and commissioning of the ATLAS x Diamond Beam Monitor (DBM). We will show results from the construction quality assurance tests, commissioning performance, including results from cosmic ray running in early 2015 and also expected first results from LHC run 2 collisions.

  2. Molecular-beam scattering

    Science.gov (United States)

    Vernon, M. F.

    1983-07-01

    The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N2 from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HC1 (FEMALE) NAC1 + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(2(2)P/sub 3/2/) and Na(3(2)P/sub 3/2) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included.

  3. Molecular-beam scattering

    Energy Technology Data Exchange (ETDEWEB)

    Vernon, M.F.

    1983-07-01

    The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N/sub 2/ from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HCl ..-->.. NaCl + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(2/sup 2/P/sub 3/2/) and Na(3/sup 2/P/sub 3/2/) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included.

  4. Molecular-beam scattering

    International Nuclear Information System (INIS)

    The molecular-beam technique has been used in three different experimental arrangements to study a wide range of inter-atomic and molecular forces. Chapter 1 reports results of a low-energy (0.2 kcal/mole) elastic-scattering study of the He-Ar pair potential. The purpose of the study was to accurately characterize the shape of the potential in the well region, by scattering slow He atoms produced by expanding a mixture of He in N2 from a cooled nozzle. Chapter 2 contains measurements of the vibrational predissociation spectra and product translational energy for clusters of water, benzene, and ammonia. The experiments show that most of the product energy remains in the internal molecular motions. Chapter 3 presents measurements of the reaction Na + HCl → NaCl + H at collision energies of 5.38 and 19.4 kcal/mole. This is the first study to resolve both scattering angle and velocity for the reaction of a short lived (16 nsec) electronic excited state. Descriptions are given of computer programs written to analyze molecular-beam expansions to extract information characterizing their velocity distributions, and to calculate accurate laboratory elastic-scattering differential cross sections accounting for the finite apparatus resolution. Experimental results which attempted to determine the efficiency of optically pumping the Li(22P/sub 3/2/) and Na(32P/sub 3/2/) excited states are given. A simple three-level model for predicting the steady-state fraction of atoms in the excited state is included

  5. Passive and active plasma deceleration for the compact disposal of electron beams

    Energy Technology Data Exchange (ETDEWEB)

    Bonatto, A., E-mail: abonatto@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); CAPES Foundation, Ministry of Education of Brazil, Brasília, DF 700040-020 (Brazil); Schroeder, C. B.; Vay, J.-L.; Geddes, C. G. R.; Benedetti, C.; Esarey, E.; Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2015-08-15

    Plasma-based decelerating schemes are investigated as compact alternatives for the disposal of high-energy beams (beam dumps). Analytical solutions for the energy loss of electron beams propagating in passive and active (laser-driven) schemes are derived. These solutions, along with numerical modeling, are used to investigate the evolution of the electron distribution, including energy chirp and total beam energy. In the active beam dump scheme, a laser-driver allows a more homogeneous beam energy extraction and drastically reduces the energy chirp observed in the passive scheme. These concepts could benefit applications requiring overall compactness, such as transportable light sources, or facilities operating at high beam power.

  6. 吸头小柱微萃取-解吸电晕束电离质谱用于快速分析体液中的降压药物%Coupling Micropipette Tip-based Micro-extraction with Desorption Corona Beam Ionization Mass Spectrometry for Rapid Analysis of Antihypertensive Drugs in Body Fluid

    Institute of Scientific and Technical Information of China (English)

    游金清; 郝艳红; 黄云清; 程玉鹏; 孙文剑; 余琼卫; 袁必锋; 冯钰锜

    2013-01-01

    We developed a convenient method by coupling micropipette tip-based micro-extraction ( TBME) with desorption corona beam ionization mass spectrometry ( DCBI-MS) for rapid analysis of medicines in biological samples. The operation of TBME is easy and fast, and it can enrich the analyte concentration and eliminate background interference, which makes it suitable as a novel sample preparation method before ambient Ionization. We have systematically optimized the extraction conditions and the instrument parameters. The typical analysis procedure includes the steps of extraction, drying and DCBI-MS detection, and the all processes take less than three minutes. The method was successfully used for the analysis of antihypertensive drugs such as nifedipine, nitrendipine and nimodipine and illegal drugs in body fluid. The method is of considerable interest for broadening the application of ambient ionization mass spectrometry for body fluid analysis.%将C18ZipTip吸头小柱微萃取(Micropipette tip-based micro-extraction)与解吸电晕束电离质谱(Desorption corona beam ionization mass spectrometry,DCBI-MS)联用,用于快速分析复杂生物样品中的小分子药物.吸头小柱微萃取装置简单、操作快速,适合作为与常压直接离子化质谱技术联用的前处理技术,能实现分析物的富集和基质干扰的消除.优化了萃取条件和离子源的参数,最终选择20%(V/V)乙腈溶液作为上样溶液,4 μL乙腈作为解吸液.分析全过程包括萃取、自然挥干、电晕束解析电离等步骤,并可以在3 min内完成.此方法用于血浆中的地平类降血压药及尿液中氯胺酮的快速分析,结果满意.这种方法拓展了常压直接离子化质谱技术在体液分析中的应用.

  7. Preparation of a beam quality indicator for effective energy determinations of continuum beams: establishment of traceability

    CERN Document Server

    Matsubayashi, M; Kobayashi, H

    1999-01-01

    A new beam quality indicator (BQI) was designed and fabricated to determine effective energies of beams extracted from neutron radiography facilities. Performances of the five new BQIs were compared with the original BQI which was recently proposed and tested by various beams. Non-filtered thermal neutrons, filtered thermal neutrons, and cold neutrons from a guide tube were used in the performance test program. The new BQIs were also examined by four different detection systems using a combination of a Gd converter and a X-ray film, a neutron imaging plate, a cooled charge coupled device camera, and a silicon intensified target tube camera.

  8. Maskless micro-ion-beam reduction lithography

    International Nuclear Information System (INIS)

    An ion projection lithography (IPL) technique called maskless micro-ion-beam reduction lithography (MMRL) is being studied for future dynamic random access memory and microprocessors manufacturing. In addition to minimum feature sizes of 50 nm or less required of next generation lithography, this MMRL system is proposed to completely eliminate the first stage of the conventional IPL system that contains the complicated beam optics design in front of the stencil mask and the mask itself. Its main components consist of a multi-cusp, rf plasma generator, a multi-beamlet extraction system, and an accelerator column for beam reduction. The viability of this MMRL system hinges upon the successful development of these components, most importantly the proposed all-electrostatic accelerator column. This article describes the different components of the MMRL system and its ion optics. Computational results of beam demagnification and optics optimization are also presented along with design progress of the prototype MMRL system. (c) 1999 American Vacuum Society

  9. Synchronous Characterization of Semiconductor Microcavity Laser Beam

    CERN Document Server

    Wang, Tao

    2015-01-01

    We report on a high-resolution double-channel imaging method used to synchronously map the intensity- and optical-frequency-distribution of a laser beam in the plane orthogonal to the propagation direction. The synchronous measurement allows us to show that the laser frequency is an inhomogeneous distribution below threshold, but that it becomes homogeneous across the fundamental Gaussian mode above threshold. The beam's tails deviations from the Gaussian shape, however, are accompanied by sizeable fluctuations in the laser wavelength, possibly deriving from manufacturing details and from the influence of spontaneous emission in the very low intensity wings. In addition to the synchronous spatial characterization, a temporal analysis at any given point in the beam cross-section is carried out. Using this method, the beam homogeneity and spatial shape, energy density, energy center and the defects-related spectrum can also be extracted from these high-resolution pictures.

  10. Synchronous characterization of semiconductor microcavity laser beam.

    Science.gov (United States)

    Wang, T; Lippi, G L

    2015-06-01

    We report on a high-resolution double-channel imaging method used to synchronously map the intensity- and optical-frequency-distribution of a laser beam in the plane orthogonal to the propagation direction. The synchronous measurement allows us to show that the laser frequency is an inhomogeneous distribution below threshold, but that it becomes homogeneous across the fundamental Gaussian mode above threshold. The beam's tails deviations from the Gaussian shape, however, are accompanied by sizeable fluctuations in the laser wavelength, possibly deriving from manufacturing details and from the influence of spontaneous emission in the very low intensity wings. In addition to the synchronous spatial characterization, a temporal analysis at any given point in the beam cross section is carried out. Using this method, the beam homogeneity and spatial shape, energy density, energy center, and the defects-related spectrum can also be extracted from these high-resolution pictures. PMID:26133832

  11. First results on proton extraction from the CERN-SPS with a bent crystal

    Science.gov (United States)

    Akbari, H.; Altuna, X.; Bardin, S.; Bellazzini, R.; Biryukov, V.; Brez, A.; Bussa, M. P.; Busso, L.; Calcaterra, A.; Carboni, G.; Costantini, F.; de Sangro, R.; Elsener, K.; Ferioli, F.; Ferrari, A.; Ferri, G. P.; Ferroni, F.; Fidecaro, G.; Freund, A.; Guinand, R.; Gyr, M.; Herr, W.; Hilaire, A.; Jensen, B. N.; Klem, J.; Lanceri, L.; Maier, K.; Massai, M. M.; Mertens, V.; Møller, S. P.; Morganti, S.; Palamara, O.; Peraire, S.; Petrera, S.; Placidi, M.; Santacesaria, R.; Scandale, W.; Schmidt, R.; Taratin, A. M.; Tosello, F.; Uggerhøj, E.; Vettermann, B.; Vita, P. F.; Vuagnin, G.; Weisse, E.; Weisz, S.

    1993-09-01

    The feasibility of extracting protons from the halo of a high energy beam by means of a bent silicon crystal has been investigated. Protons diffusing from a GeV beam circulating in the SPS at CERN have been extracted at an angle of 8.5 mrad. Efficiencies of abour 10 percent, orders of magnitude higher than the values achieved previously, have been measured. The present results are promising in view of beam extraction from future multi-TeV proton accelerators.

  12. Energy verification in Ion Beam Therapy

    CERN Document Server

    Moser, F; Dorda, U

    2011-01-01

    The adoption of synchrotrons for medical applications necessitates a comprehensive on-line verification of all beam parameters, autonomous of common beam monitors. In particular for energy verification, the required precision of down to 0.1MeV in absolute terms, poses a special challenge regarding the betatron-core driven 3rd order extraction mechanism which is intended to be used at MedAustron [1]. Two different energy verification options have been studied and their limiting factors were investigated: 1) A time-of-flight measurement in the synchrotron, limited by the orbit circumference information and measurement duration as well as extraction uncertainties. 2) A calorimeter-style system in the extraction line, limited by radiation hardness and statistical fluctuations. The paper discusses in detail the benefits and specific aspects of each method.

  13. Pyramid beam splitter

    Science.gov (United States)

    McKeown, Mark H.; Beason, Steven C.; Fairer, George

    1992-01-01

    The apparatus of the present invention provides means for obtaining accurate, dependable, measurement of bearings and directions for geologic mapping in subterranean shafts, such as, for example, nuclear waste storage investigations. In operation, a laser beam is projected along a reference bearing. A pyramid is mounted such that the laser beam is parallel to the pyramid axis and can impinge on the apex of the pyramid thus splitting the beam several ways into several beams at right angles to each other and at right angles to the reference beam. The pyramid is also translatable and rotatable in a plane perpendicular to the reference beam.

  14. Low current beam techniques

    Energy Technology Data Exchange (ETDEWEB)

    Saint, A.; Laird, J.S.; Bardos, R.A.; Legge, G.J.F. [Melbourne Univ., Parkville, VIC (Australia). School of Physics; Nishijima, T.; Sekiguchi, H. [Electrotechnical Laboratory, Tsukuba (Japan).

    1993-12-31

    Since the development of Scanning Transmission Microscopy (STIM) imaging in 1983 many low current beam techniques have been developed for the scanning (ion) microprobe. These include STIM tomography, Ion Beam Induced Current, Ion Beam Micromachining and Microlithography and Ionoluminense. Most of these techniques utilise beam currents of 10{sup -15} A down to single ions controlled by beam switching techniques This paper will discuss some of the low beam current techniques mentioned above, and indicate, some of their recent applications at MARC. A new STIM technique will be introduced that can be used to obtain Z-contrast with STIM resolution. 4 refs., 3 figs.

  15. External proton and Li beams

    International Nuclear Information System (INIS)

    In the frame of a feasibility study to introduce proton therapy in Argentina in a collaborative agreement between the Physics and Radiobiology Departments of the National Atomic Energy Commission or Argentina and the Centre de Protontherapie de Orsay, France, external proton and Li beams were produced at the TANDAR accelerator in Buenos Aires. The specific aim of this work was to start radiobiology studies on cell cultures and small laboratory animals. In particular we seek to determine here the relative biological effectiveness, RBE, for proton and Li beams as a function of energy for different tumor and normal cell lines. The 24 MeV proton beam was diffused using a 25 μm gold foil and extracted through a Kapton window to obtain a homogeneous field (constant to 95%) of about 7 cm in diameter. Measurements were carried out with quasi-monoenergetic beams (of 20.2 ± 0.07 MeV, 2.9 ± 0.10 MeV y 1.5 ± 0.1 MeV for protons and 21.4 ± 0.4 MeV for Lithium). Proton fluence and Bragg peaks were measured. The dose delivered in each case was monitored on-line with a calibrated transmission ionization chamber. Three cell lines PDV, PDVC 57 and V 79 (as a reference) were irradiated with γ-rays, proton and lithium beams with linear energy transfer (LET) from 2 to 100 keV/μm. RBE values in the range of 1.2-5.9 were obtained. In addition preliminary studies on chromosomal aberrations and viability of alveolar macrophages were carried out. (author)

  16. Beam line to S155

    CERN Multimedia

    1977-01-01

    The experiment S155 was designed by the Orsay (CSNM-CNRS) Collaboration to observe the properties of exotic light nuclei. It was installed in the PS neutrino tunnel. The photo shows a mass spectrometer (in the background) on line with the PS proton beam which arrives (bottom, right) from the fast extraction FE74. Roger Fergeau stands on the left. The alkaline isotopes produced in the carbon-uranium target heated at 2000°C were swiftly extracted, mass separated, and brought to a detector behind the shielding. Sodium 34 (11 protons and 23 neutrons) was observed and its half-life of only 5 ms was measured. The excited levels 2+ of Magnesium 30 and Magnesium 32 (Sodium descendants) were localised, and the magic number 20 was found to vanish. Thus, the discovery made earlier for Sodium 30 and Sodium 32, with the same apparatus, was confirmed. (See also photo 7706511.)

  17. Transverse beam emittance measurement using quadrupole variation at KIRAMS-430

    Science.gov (United States)

    An, Dong Hyun; Hahn, Garam; Park, Chawon

    2015-02-01

    In order to produce a 430 MeV/u carbon ion (12 C 6+) beam for medical therapy, the Korea Institute of Radiological & Medical Sciences (KIRAMS) has carried out the development of a superconducting isochronous cyclotron, the KIRAMS-430. At the extraction of the cyclotron, an Energy Selection System (ESS) is located to modulate the fixed beam energy and to drive the ion beam through High Energy Beam Transport (HEBT) into the treatment room. The beam emittance at the ion beamline is to be measured to provide information on designing a beam with high quality. The well-known quadrupole variation method was used to determine the feasibility of measuring the transverse beam emittance. The beam size measured at the beam profile monitor (BPM) is to be utilized and the transformation of beam by transfer matrix is to be applied being taken under various transport condition of varying quadrupole magnetic strength. Two different methods where beam optics are based on the linear matrix formalism and particle tracking with a 3-D magnetic field distribution obtained by using OPERA3D TOSCA, are applied to transport the beam. The fittings for the transformation parameters are used to estimate the transverse emittance and the twiss parameters at the entrance of the quadrupole in the ESS. Including several systematic studies, we conclude that within the uncertainty the estimated emittances are consistent with the ones calculated by using Monte Carlo simulations.

  18. Beam Dynamics and Beam Losses - Circular Machines

    CERN Document Server

    Kain, V

    2016-01-01

    A basic introduction to transverse and longitudinal beam dynamics as well as the most relevant beam loss mechanisms in circular machines will be presented in this lecture. This lecture is intended for physicists and engineers with little or no knowledge of this subject.

  19. Beam-beam issues in asymmetric colliders

    Energy Technology Data Exchange (ETDEWEB)

    Furman, M.A.

    1992-07-01

    We discuss generic beam-beam issues for proposed asymmetric e{sup +}- e{sup -} colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II).

  20. Optimization of a charge-state analyzer for electron cyclotron resonance ion source beams

    NARCIS (Netherlands)

    Saminathan, S.; Beijers, J. P. M.; 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+ 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 b

  1. Vacuum extraction

    DEFF Research Database (Denmark)

    Maagaard, Mathilde; Oestergaard, Jeanett; Johansen, Marianne;

    2012-01-01

    with daily work in the obstetric field were tested. Methods. The Delphi method was used for development of the scale. In a simulated vacuum extraction scenario first-year residents and obstetric chief physicians were rated using the developed OSATS scale for vacuum extraction to test construct validity...... of the scale. Main outcome measures. Consensus for the content of the scale. To test the scale Cronbachs alpha, interclass correlation and differential item function was calculated in the prospective study. Results. 89% completed the first and 61% completed the second Delphi round. Hereafter, consensus......Objectives. To develop and validate an Objective Structured Assessment of Technical Skills (OSATS) scale for vacuum extraction. Design. Two part study design: Primarily, development of a procedure-specific checklist for vacuum extraction. Hereafter, validationof the developed OSATS scale for vacuum...

  2. Laser-Beam Separator

    Science.gov (United States)

    Mcdermid, I. S.

    1984-01-01

    Train of prisms and optical stop separate fundamental beam of laser from second and higher order harmonics of beam produced in certain crystals and by stimulated Raman scattering in gases and liquids.

  3. Beam Loss in Linacs

    CERN Document Server

    Plum, M A

    2016-01-01

    Beam loss is a critical issue in high-intensity accelerators, and much effort is expended during both the design and operation phases to minimize the loss and to keep it to manageable levels. As new accelerators become ever more powerful, beam loss becomes even more critical. Linacs for H- ion beams, such as the one at the Oak Ridge Spallation Neutron Source, have many more loss mechanisms compared to H+ (proton) linacs, such as the one being designed for the European Spallation Neutron Source. Interesting H- beam loss mechanisms include residual gas stripping, H+ capture and acceleration, field stripping, black-body radiation and the recently discovered intra-beam stripping mechanism. Beam halo formation, and ion source or RF turn on/off transients, are examples of beam loss mechanisms that are common for both H+ and H- accelerators. Machine protection systems play an important role in limiting the beam loss.

  4. Space charge dominated beams

    International Nuclear Information System (INIS)

    After an introductory section on the relationship between emittance and beam Coulomb energy we discuss the properties of space charge dominated beams in progressive steps: from uniformly charged bunched beams to non-uniformly charged beams to correlation effects between particles (simulation beams or 'crystalline' beams). A practical application can be found in the beam dynamics of a high-current injector. The concept of correlation energy is of practical interest in computer simulation of high-brilliance beams, where one deals with an artificially enhanced two-particle Coulomb energy, if many real particles are combined into one simulation super-particle. This can be a source of non-physical emittance growth. (orig./HSI)

  5. High energy beam lines

    Science.gov (United States)

    Marchetto, M.; Laxdal, R. E.

    2014-01-01

    The ISAC post accelerator comprises an RFQ, DTL and SC-linac. The high energy beam lines connect the linear accelerators as well as deliver the accelerated beams to two different experimental areas. The medium energy beam transport (MEBT) line connects the RFQ to the DTL. The high energy beam transport (HEBT) line connects the DTL to the ISAC-I experimental stations (DRAGON, TUDA-I, GPS). The DTL to superconducting beam (DSB) transport line connects the ISAC-I and ISAC-II linacs. The superconducting energy beam transport (SEBT) line connects the SC linac to the ISAC-II experimental station (TUDA-II, HERACLES, TIGRESS, EMMA and GPS). All these lines have the function of transporting and matching the beams to the downstream sections by manipulating the transverse and longitudinal phase space. They also contain diagnostic devices to measure the beam properties.

  6. Drift distance survey in direct plasma injection scheme for high current beam production

    International Nuclear Information System (INIS)

    In a laser ion source, plasma drift distance is one of the most important design parameters. Ion current density and beam pulse width are defined by plasma drift distance between a laser target and beam extraction position. In direct plasma injection scheme, which uses a laser ion source and a radio frequency quadrupole linac, we can apply relatively higher electric field at beam extraction due to the unique shape of a positively biased electrode. However, when we aim at very high current acceleration such as several tens of milliamperes, we observed mismatched beam extraction conditions. We tested three different ion current at ion extraction region by changing plasma drift distance to study better extraction condition. In this experiment, C6+ beam was accelerated. We confirmed that matching condition can be improved by controlling plasma drift distance.

  7. The Superconducting Magnets of the ILC Beam Delivery System

    Energy Technology Data Exchange (ETDEWEB)

    Parker, B.; Anerella, M.; Escallier, J.; He, P.; Jain, A.; Marone, A.; /Brookhaven; Nosochkov, Y.; Seryi, Andrei; /SLAC

    2007-09-28

    The ILC Beam Delivery System (BDS) uses a variety of superconducting magnets to maximize luminosity and minimize background. Compact final focus quadrupoles with multifunction correction coils focus incoming beams to few nanometer spot sizes while focusing outgoing disrupted beams into a separate extraction beam line. Anti-solenoids mitigate effects from overlapping focusing and the detector solenoid field. Far from the interaction point (IP) strong octupoles help minimize IP backgrounds. A low-field but very large aperture dipole is integrated with the detector solenoid to reduce backgrounds from beamstrahlung pairs generated at the IP. Physics requirements and magnetic design solutions for the BDS superconducting magnets are reviewed in this paper.

  8. Recovery of CTF beam signals from a strong wakefield background

    International Nuclear Information System (INIS)

    The beam monitor for the CERN Linear Collider Test Facility (CTF) has to work not only with very short pulses (350 ps FWHM) at a spacing of 330 ps, but also in a strong wakefield background. A cone-shaped button pickup electrode has been designed and constructed for use with CTF beams and tests have been made using a real time analogue Gaussian filter to recover the beam signals from the strong wakefield signals. As a comparison to the analogue filter, a study has been made to process the data off-line and extract the beam signals using digital filtering based on the wavelet concept. (author). 3 refs., 7 figs

  9. Beam Position Monitor Electronics Upgrade for Fermilab Switchyard

    CERN Document Server

    Stabile, P; Fitzgerald, J A; Liu, N; Morris, D K; Prieto, P S; Seraphin, J P

    2015-01-01

    The beam position monitor (BPM) system for Fermilab Switchyard (SY) provides the position, intensity and integrated intensity of the 53.10348 MHz RF bunched resonant extracted beam from the Main Injector over 4 seconds of spill. The total beam intensity varies from 1x10^11 to 1x10^13 protons. The spill is measured by stripline beam postion monitors and resonant circuit. The BPMs have an external resonant circuit tuned to 53.10348 MHz. The corresponding voltage signal out of the BPM has been estimated to be between -110 dBm and -80 dBm.

  10. Proton beam writing

    OpenAIRE

    Frank Watt; Breese, Mark B H; Bettiol, Andrew A; Jeroen A. van Kan

    2007-01-01

    Proton beam (p-beam) writing is a new direct-writing process that uses a focused beam of MeV protons to pattern resist material at nanodimensions. The process, although similar in many ways to direct writing using electrons, nevertheless offers some interesting and unique advantages. Protons, being more massive, have deeper penetration in materials while maintaining a straight path, enabling p-beam writing to fabricate three-dimensional, high aspect ratio structures with vertical, smooth side...

  11. Welding by laser beam

    International Nuclear Information System (INIS)

    A laser which does not require a vacuum and the beam from which can be projected over a distance without loss of power is sited outside a welding zone and the beam projected through a replaceable laser transparent window. The window is designed and shaped to facilitate access of the beam of workpiece items to be welded in containment. Either the workpiece or the laser beam may be moved during welding. (author)

  12. Slow kaon beams

    International Nuclear Information System (INIS)

    A short description is given of considerations for the design of low-momentum kaon beam lines. Relevant data for the performance of seven existing and decommissioned slow kaon beams are presented. For single-stage separated beams the observed ratio all/K- is greater than 50 for momenta less than 500 MeV/c. We recommend a two-stage separated beam with perhaps an upstream cleanup section for maximal purity

  13. Beam Dynamics for ARIA

    CERN Document Server

    Ekdahl, Carl

    2015-01-01

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  14. PARTICLE BEAM TRACKING CIRCUIT

    Science.gov (United States)

    Anderson, O.A.

    1959-05-01

    >A particle-beam tracking and correcting circuit is described. Beam induction electrodes are placed on either side of the beam, and potentials induced by the beam are compared in a voltage comparator or discriminator. This comparison produces an error signal which modifies the fm curve at the voltage applied to the drift tube, thereby returning the orbit to the preferred position. The arrangement serves also to synchronize accelerating frequency and magnetic field growth. (T.R.H.)

  15. Electron beam focusing system

    Energy Technology Data Exchange (ETDEWEB)

    Dikansky, N.; Nagaitsev, S.; Parkhomchuk, V.

    1997-09-01

    The high energy electron cooling requires a very cold electron beam. Thus, the electron beam focusing system is very important for the performance of electron cooling. A system with and without longitudinal magnetic field is presented for discussion. Interaction of electron beam with the vacuum chamber as well as with the background ions and stored antiprotons can cause the coherent electron beam instabilities. Focusing system requirements needed to suppress these instabilities are presented.

  16. Beam Dynamics for ARIA

    Energy Technology Data Exchange (ETDEWEB)

    Ekdahl, Carl August Jr. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-10-14

    Beam dynamics issues are assessed for a new linear induction electron accelerator being designed for flash radiography of large explosively driven hydrodynamic experiments. Special attention is paid to equilibrium beam transport, possible emittance growth, and beam stability. It is concluded that a radiographic quality beam will be produced possible if engineering standards and construction details are equivalent to those on the present radiography accelerators at Los Alamos.

  17. Production of radioactive molecular beams for CERN-ISOLDE

    CERN Document Server

    AUTHOR|(SzGeCERN)703149; Kröll, Thorsten

    SOLDE, the Isotope Separation On-Line facility, at CERN is a leading facility for the production of beams of exotic radioactive isotopes. Currently over 1000 different isotopes with half lives down to milliseconds can be extracted with beam intensities of up to 10^11 ions per second. However, due to the reactive target environment not all isotopes are extractable in sufficient amounts. In this work the extraction of short lived carbon and boron isotopes is investigated. Therefore a variety of experimental and computanional techniques have been used.

  18. Production of radioactive molecular beams for CERN-ISOLDE

    Energy Technology Data Exchange (ETDEWEB)

    Seiffert, Christoph

    2015-06-15

    ISOLDE, the Isotope Separation On-Line facility, at CERN is a leading facility for the production of beams of exotic radioactive isotopes. Currently over 1000 different isotopes with half lives down to milliseconds can be extracted with beam intensities of up to 10{sup 11} ions per second. However, due to the reactive target environment not all isotopes are extractable in sufficient amounts. In this work the extraction of short lived carbon and boron isotopes is investigated. Therefore a variety of experimental and computational techniques have been used.

  19. Production of radioactive molecular beams for CERN-ISOLDE

    International Nuclear Information System (INIS)

    ISOLDE, the Isotope Separation On-Line facility, at CERN is a leading facility for the production of beams of exotic radioactive isotopes. Currently over 1000 different isotopes with half lives down to milliseconds can be extracted with beam intensities of up to 1011 ions per second. However, due to the reactive target environment not all isotopes are extractable in sufficient amounts. In this work the extraction of short lived carbon and boron isotopes is investigated. Therefore a variety of experimental and computational techniques have been used.

  20. Beams 92: Proceedings

    International Nuclear Information System (INIS)

    This report contains papers on the following topics: Ion beam papers; electron beam, bremsstrahlung, and diagnostics papers; radiating Z- pinch papers; microwave papers; electron laser papers; advanced accelerator papers; beam and pulsed power applications papers; pulsed power papers; and these papers have been indexed separately elsewhere

  1. Accelerating nondiffracting beams

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Shaohui; Li, Manman; Yao, Baoli, E-mail: yaobl@opt.ac.cn; Yu, Xianghua; Lei, Ming; Dan, Dan; Yang, Yanlong; Min, Junwei; Peng, Tong

    2015-06-05

    We present a set of beams which combine the properties of accelerating beams and (conventional) diffraction-free beams. These beams can travel along a desired trajectory while keeping an approximately invariant transverse profile, which may be (higher-order) Bessel-, Mathieu- or parabolic-nondiffracting-like beams, depending on the initial complex amplitude distribution. A possible application of these beams presented here may be found in optical trapping field. For example, a higher-order Bessel-like beam, which has a hollow (transverse) pattern, is suitable for guiding low-refractive-index or metal particles along a curve. - Highlights: • A set of beams having arbitrary trajectories of accelerating and nondiffracting behaviors are generalized and presented. • Bessel-like accelerating beams are generalized to the higher-order (hollow) version. • Mathieu-like accelerating beams and parabolic-nondiffracting-like accelerating beams are presented. • A possible application of these beams may be found in optical trapping and guiding of particles.

  2. An Electromagnetic Beam Converter

    DEFF Research Database (Denmark)

    2009-01-01

    The present invention relates to an electromagnetic beam converter and a method for conversion of an input beam of electromagnetic radiation having a bell shaped intensity profile a(x,y) into an output beam having a prescribed target intensity profile l(x',y') based on a further development...

  3. Klystron beam bunching

    International Nuclear Information System (INIS)

    A detailed description of electron-beam bunching phenomena in klystrons is presented. Beam harmonic current is defined, both space-charge and ballistic bunching are analyzed, Ramo's theorem is used to describe how a bunched beam drives a cavity, and a general cavity model including external coupling is provided. (author)

  4. Target development for a radioactive ion beam

    Energy Technology Data Exchange (ETDEWEB)

    Arnould, M.; Vanhorenbeeck, J. (Universite Libre de Bruxelles (Belgium). Inst. d' Astronomie et d' Astrophysique); Baeten, F.; Dom, C. (Institut National des Radioelements, Fleurus (Belgium)); Darquennes, D.; Delbar, T.; Jongen, Y.; Lacroix, M.; Lipnik, P.; Loiselet, M.; Ryckewaert, G.; Wa Kitwanga, S.; Vervier, J.; Zaremba, S. (Louvain Univ., Louvain-la-Neuve (Belgium). Centre de Physique Nucleaire; Louvain Univ., Louvain-la-Neuve (Belgium). Lab. de Cyclotron); Huyse, M.; Reusen, G.; Duppen, P. van (Leuven Univ. (Belgium). Inst. voor Kern- en Stralingsfysika)

    1989-10-01

    A proton bombarded target coupled to an ion source is a key-equipment to produce a cyclotron accelerated Radioactive Ion Beam (RIB). This note concerns the target development for a {sup 13}N ion beam which will be the first one out of a more general project at Louvain-la-Neuve (Report RIB-1988-01). A 30-MeV proton beam of up to 300-{mu}A intensity from the CYCLONE 30 bombards a graphite target to produce the {sup 13}N isotope via the {sup 13}C(p, n){sup 13}N reaction. Two major problems have to be solved: The extraction and transport of {sup 13}N and the beam-heat dissipation. These aspects are somewhat correlated to the temperature dependence of the {sup 13}N release and to the heat conductivity of graphite. A disk shaped target can be cooled through its side-face or through its back-face, and in fact both designs are explored. The extraction yield of the first one varies with the beam intensity up to a maximum value of 46% at 170 {mu}A. For the second one, which is presently under development, the target temperature can be adjusted by a cooled finger of variable length. (orig.).

  5. Laser driven proton acceleration and beam shaping

    OpenAIRE

    Sinigardi, Stefano

    2014-01-01

    In the race to obtain protons with higher energies, using more compact systems at the same time, laser-driven plasma accelerators are becoming an interesting possibility. But for now, only beams with extremely broad energy spectra and high divergence have been produced. The driving line of this PhD thesis was the study and design of a compact system to extract a high quality beam out of the initial bunch of protons produced by the interaction of a laser pulse with a thin solid target, usi...

  6. FNAL main ring to energy save antiproton transfer system for Tevatron I

    International Nuclear Information System (INIS)

    A system for antiproton beam transfer from the Main Ring to the Energy Saver for colliding beam operations has been designed and fabricated. The system is similar to the existing proton beam transfer system used for fixed target operation of the Energy Saver. Using a fast kicker in the Main Ring, one or several bunches of 150 GeV pbars will be kicked horizontally across the septa of two Lambertsons into a short transfer line. At the end of this line, they are injected into the Energy Saver through two more Lambertsons and kicked onto a closed orbit by a second fast kicker. For commissioning and tune-up, the system will be operated in reverse, extracting 150 GeV protons from the Energy Saver to the Main Ring. In addition to a description of the design of the system and its components, the status of the installation and commissioning will also be discussed

  7. Pushing the limits - beam

    CERN Document Server

    Métral, E

    2011-01-01

    Many collective effects were observed in 2010, first when the intensity per bunch was increased and subsequently when the number of bunches was pushed up and the bunch spacing was reduced. After a review of the LHC performance during the 2010 run, with a particular emphasis on impedances and related single-beam coherent instabilities, but mentioning also beam-beam and electron cloud issues, the potential of the LHC for 2011 will be discussed. More specifically, the maximum bunch/beam intensity and the maximum beam brightness the LHC should be able to swallow will be compared to what the injectors can provide.

  8. Beam-helicity and beam-charge asymmetries associated with deeply virtual Compton scattering on the unpolarised proton

    Energy Technology Data Exchange (ETDEWEB)

    Airapetian, A. [Giessen Univ. (Germany). Physikalisches Inst.; Michigan Univ., Ann Arbor, MI (United States). Randall Laboratory of Physics; Akopov, N. [Yerevan Physics Institute (Armenia); Akopov, Z. [DESY Hamburg (DE)] (and others)

    2012-03-15

    Beam-helicity and beam-charge asymmetries in the hard exclusive leptoproduction of real photons from an unpolarised hydrogen target by a 27.6 GeV lepton beam are extracted from the HERMES data set of 2006-2007 using a missing-mass event selection technique. The asymmetry amplitudes extracted from this data set are more precise than those extracted from the earlier data set of 1996-2005 previously analysed in the same manner by HERMES. The results from the two data sets are compatible with each other. Results from these combined data sets are extracted and constitute the most precise asymmetry amplitude measurements made in the HERMES kinematic region using a missing-mass event selection technique. (orig.)

  9. Beam-helicity and beam-charge asymmetries associated with deeply virtual Compton scattering on the unpolarised proton

    CERN Document Server

    Airapetian, A; Akopov, Z; Aschenauer, E C; Augustyniak, W; Avakian, R; Avetissian, A; Avetisyan, E; Blok, H P; Borissov, A; Bowles, J; Bryzgalov, V; Burns, J; Capiluppi, M; Capitani, G P; Cisbani, E; Ciullo, G; Contalbrigo, M; Dalpiaz, P F; Deconinck, W; De Leo, R; De Nardo, L; De Sanctis, E; Diefenthaler, M; Di Nezza, P; Düren, M; Ehrenfried, M; Elbakian, G; Ellinghaus, F; Fantoni, A; Felawka, L; Frullani, S; Gabbert, D; Gapienko, G; Gapienko, V; Garibaldi, F; Gavrilov, G; Giordano, F; Gliske, S; Golembiovskaya, M; Hadjidakis, C; Hartig, M; Hasch, D; Hoek, M; Holler, Y; Imazu, Y; Jackson, H E; Jo, H S; Kaiser, R; Karyan, G; Keri, T; Kinney, E; Kisselev, A; Kobayashi, N; Korotkov, V; Kozlov, V; Kravchenko, P; Krivokhijine, V G; Lagamba, L; Lapikás, L; Lehmann, I; Lenisa, P; Lorenzon, W; Ma, B -Q; Mahon, D; Makins, N C R; Manaenkov, S I; Manfré, L; Mao, Y; Marianski, B; de la Ossa, A Martinez; Marukyan, H; Miller, C A; Miyachi, Y; Movsisyan, A; Muccifora, V; Murray, M; Mussgiller, A; Nappi, E; Naryshkin, Y; Nass, A; Nowak, W -D; Pappalardo, L L; Perez-Benito, R; Petrosyan, A; Raithel, M; Reimer, P E; Reolon, A R; Riedl, C; Rith, K; Rosner, G; Rostomyan, A; Rubin, J; Ryckbosch, D; Salomatin, Y; Sanftl, F; Schäfer, A; Schnell, G; Schüler, K P; Seitz, B; Shibata, T -A; Shutov, V; Stancari, M; Statera, M; Steffens, E; Steijger, J J M; Stewart, J; Taroian, S; Terkulov, A; Truty, R; Trzcinski, A; Tytgat, M; Van Haarlem, Y; Van Hulse, C; Veretennikov, D; Vikhrov, V; Vilardi, I; Wang, S; Yaschenko, S; Ye, Z; Yen, S; Yu, W; Zagrebelnyy, V; Zeiler, D; Zihlmann, B; Zupranski, P

    2012-01-01

    Beam-helicity and beam-charge asymmetries in the hard exclusive leptoproduction of real photons from an unpolarised hydrogen target by a 27.6 GeV lepton beam are extracted from the HERMES data set of 2006-2007 using a missing-mass event selection technique. The asymmetry amplitudes extracted from this data set are more precise than those extracted from the earlier data set of 1996-2005 previously analysed in the same manner by HERMES. The results from the two data sets are compatible with each other. Results from these combined data sets are extracted and constitute the most precise asymmetry amplitude measurements made in the HERMES kinematic region using a missing-mass event selection technique.

  10. Beam Transfer Systems for the LAGUNA-LBNO Long Baseline Neutrino Beam from the CERN SPS

    CERN Document Server

    Goddard, B; Efthymiopoulos, I; Papaphilippou, Y; Parfenova, A

    2013-01-01

    For the Long Baseline neutrino facility under study at CERN (LAGUNA-LBNO) it is initially planned to extract a 400 GeV beam from the second long straight section in the SPS into the existing transfer channel TT20 leading to the North Area experimental zone, to a new target aligned with a far detector at a distance of 2300 km [1]. In a second phase a new High-Power Proton Synchrotron (HPPS) accelerator is proposed, to give a 2 MW beam at about 50 GeV on the same target. In this paper the required beam transfer systems are outlined, including the new sections of transfer line between the Superconducting Proton Linac (SPL), HP-PS and SPS, and from the SPS to the target, and also the injection and extraction systems in the long straight section of the HPPS. The feasibility of a 4 GeV H- injection system is discussed.

  11. Cluster ion beam evaporation

    International Nuclear Information System (INIS)

    Cluster ions can be made by the supercooling due to adiabatic expansion of substances to be vaporized which are ejected from a nozzle. This paper is described on the recent progress of studies concerning the cluster beam. The technique of cluster ion beam has been applied for the studies of thermonuclear plasma, the fabrication of thin films, crystal growth and electronic devices. The density of cluster ion beam is larger than that of atomic ion beam, and the formation of thin films can be easily done in high vacuum. This method is also useful for epitaxial growth. Metallic vapour cluster beam was made by the help of jetting rare gas beam. Various beam sources were developed. The characteristics of these sources were measured and analyzed. (Kato, T.)

  12. THE FONT5 PROTOTYPE ILC INTRA-TRAIN FEEDBACK SYSTEM AT ATF2

    CERN Document Server

    Apsimon, R J; Burrows, P N; Christian, G B; Constance, B; Perry, C; Resta-Lopez, J

    2011-01-01

    We present the design and beam test results of a prototype beam-based digital feedback system for the Interaction Point of the International Linear Collider. A custom analogue front-end signal processor, FPGA-based digital signal processing boards, and kicker drive amplifier have been designed, built, deployed and tested with beam in the extraction line of the KEK Accelerator Test Facility (ATF2). The system was used to provide orbit correction to the train of bunches extracted from the ATF damping ring. The latency was measured to be approximately 140 ns.

  13. Design of slow extraction system at Booster Synchrotron for MUSES

    International Nuclear Information System (INIS)

    The Booster Synchrotron Ring (BSR) is a part of Multi-USe Experimental Storage rings (MUSES). BSR functions exclusively for the acceleration of ion and electron beams. The maximum accelerating energy is, for example, to be 3 GeV for proton; 1.45 GeV/nucleon for light ions of q/A=1/2; 800 MeV/nucleon for heavy ions of q/A=1/3. Electron beam is accelerated to 2.5 GeV from the injection energy 300 MeV. The accelerated ion and electron beams will be fast extracted and injected into the Double Storage Rings (DSR) by one turn injection. As another operation mode, ion beams will be slowly extracted for the experiments. In this paper, injection and extraction procedures of the BSR, especially slow extraction, are presented. (author)

  14. Development of non-contact beam intensity monitor by residual gas ionization

    International Nuclear Information System (INIS)

    Non-contact beam intensity monitor is an important device for high-intensity proton accelerator, such as J-PARC. Especially, it is difficult to measure beam intensity of DC-like beam with off-contact. We have developed non-contact beam intensity monitor for J-PARC slow-extraction beam line by measuring charge of ionization electrons in 1 Pa residual gas. In this article, specifications of the residual gas ionization current monitor (RGICM) and results of a test experiment with 65 MeV proton beam at Research Center for Nuclear Physics in Osaka University are reported. (author)

  15. Preliminary considerations for a surface muon beam line at the SNS

    International Nuclear Information System (INIS)

    A design to transport a beam of low momentum surface muons (29 MeV/c) is presented. The muon beam is obtained from the decay of pions at rest within a transmission target in the 800 MeV extracted proton beam of the Spallation Neutron Source (SNS) being constructed at the Rutherford and Appleton Laboratories. Three different solutions, using beam compression or beam chopping techniques, are presented. A beam line capable of transporting both μ+ and μ- is also briefly outlined. (author)

  16. Beam Loss Patterns at the LHC Collimators Measurements & Simulations

    CERN Document Server

    Böhlen, Till Tobias

    2008-01-01

    The Beam Loss Monitoring (BLM) system of the Large Hadron Collider (LHC) detects particle losses of circulating beams and initiates an emergency extraction of the beam in case that the BLM thresholds are exceeded. This protection is required as energy deposition in the accelerator equipment due to secondary shower particles can reach critical levels; causing damage to the beam-line components and quenches of superconducting magnets. Robust and movable beam line elements, so-called collimators, are the aperture limitations of the LHC. Consequently, they are exposed to the excess of lost beam particles and their showers. Proton loss patterns at LHC collimators have to be determined to interpret the signal of the BLM detectors and to set adequate BLM thresholds for the protection of collimators and other equipment in case of unacceptably increased loss rates. The first part of this work investigates the agreement of BLM detector measurements with simulations for an LHC-like collimation setup. The setup consists ...

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

    CERN Document Server

    AUTHOR|(CDS)2080862

    2015-01-01

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

  18. Colliding Crystalline Beams

    International Nuclear Information System (INIS)

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. We study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. We initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then over-lapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, we find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong coding, although theoretically achievable, is a challenge in practice

  19. On the propagation of a low energy oxygen ion beam

    International Nuclear Information System (INIS)

    Positive ion beams, in the range from about tens eV to several hundred eV are frequently used in RIE and RIBE etching systems. The experimental limitations in this energy range are severe and there are still many unsolved problems. Optimal ion beam focusing and maximum current beam at the substrate target are assured by the adequate ion beam neutralization. The electrons from the target plasma and also the secondary ones resulted from the ion-grid and ion-neutral interactions form a negative space charge that is involved in the ion beam neutralization. After the extraction, both the angular divergence and damping of the beam are essential to settle the position of the substrate. The beam angular divergence is established by the ion trajectories in the extraction region and also is strongly influenced by the ion beam neutralization. The shape and thickness of the space charge near the grid, which in turn is determined by the beam intensity, grid characteristics and target plasma parameters is necessary to be investigated. Positive ion bombardment plays an important role in the plasma treatments of polymers. This was the reason that investigations about the surface modifications of polymers in a positive oxygen ion beam-low density plasma (IB-LDP) system were carried out by our group [2-6]. In such system the electrons of the low-density target plasma neutralize the positive space charge of the beam and also that brought by the beam onto the polymer (insulator) surface. Results concerning the investigations of the IB-LDP system, in oxygen, by Langmuir probe method, in different experimental conditions are given in the present paper. They are compared with those obtained by using Monte Carlo method for elementary processes (ion charge transfer, electronic ionisation) in 'particle in cell' numerical simulation. (authors)

  20. Dose rate measurements around the electron extraction at FLASH

    OpenAIRE

    Leuschner, Albrecht

    2015-01-01

    The free-electron-laser FLASH at DESY was upgraded with a second undulator beam line in a separate tunnel. The safety concept regarding the electron beam extraction was confirmed by measurements. Here, LB 6419 devices of the PANDORA - system were used.

  1. Beam-beam effect seen through forced vibration

    International Nuclear Information System (INIS)

    In electron accelerator, tune is measured by giving beam transverse forced vibration caused by RF frequency. It is well known that beam-beam parameter can be measured if beam-beam interaction exists. Generally, small value is chosen as the amplitude of forced vibration, and many researches were done in this case. In this report, we discuss effect of resonance caused by beam-beam interaction in case of amplitude of forced vibration being big. (author)

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

    Science.gov (United States)

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

    2015-12-01

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

  3. Investigation of accelerated neutral atom beams created from gas cluster ion beams

    Energy Technology Data Exchange (ETDEWEB)

    Kirkpatrick, A., E-mail: akirkpatrick@exogenesis.us [Exogenesis Corporation, 20 Fortune Drive, Billerica, MA 01821 (United States); Kirkpatrick, S.; Walsh, M.; Chau, S.; Mack, M.; Harrison, S.; Svrluga, R.; Khoury, J. [Exogenesis Corporation, 20 Fortune Drive, Billerica, MA 01821 (United States)

    2013-07-15

    A new concept for ultra-shallow processing of surfaces known as accelerated neutral atom beam (ANAB) technique employs conversion of energetic gas cluster ions produced by the gas cluster ion beam (GCIB) method into intense collimated beams of coincident neutral gas atoms having controllable average energies from less than 10 eV per atom to beyond 100 eV per atom. A beam of accelerated gas cluster ions is first produced as is usual in GCIB, but conditions within the source ionizer and extraction regions are adjusted such that immediately after ionization and acceleration the clusters undergo collisions with non-ionized gas atoms. Energy transfer during these collisions causes the energetic cluster ions to release many of their constituent atoms. An electrostatic deflector is then used to eliminate charged species, leaving the released neutral atoms to still travel collectively at the same velocities they had as bonded components of their parent clusters. Upon target impact, the accelerated neutral atom beams produce effects similar to those normally associated with GCIB, but to shallower depths, with less surface damage and with superior subsurface interfaces. The paper discusses generation and characterization of the accelerated neutral atom beams, describes interactions of the beams with target surfaces, and presents examples of ongoing work on applications for biomedical devices.

  4. Proton extraction from the CERN SPS using bent silicon crystals

    Science.gov (United States)

    Elsener, K.; Fidecaro, G.; Gyr, M.; Herr, W.; Klem, J.; Mikkelsen, U.; Møller, S. P.; Uggerhøj, E.; Vuagnin, G.; Weisse, E.

    1996-10-01

    The extraction of high energy particles from a circular accelerator by means of channeling in bent crystals is an attractive alternative to classical extraction schemes, in particular for high energy proton colliders where a classical scheme becomes expensive and incompatible with normal operation. This paper reviews the ongoing extraction experiments at the CERN-SPS with bent silicon crystals. It describes the principles of beam extraction by means of a bent crystal and the different extraction schemes used: first- and multi-pass extraction and the methods to create diffusion. The limitations in tuning the accelerator to the desired impact parameters and crucial items concerning crystal preparation, bending and pre-alignment are discussed. The experimental procedures including an overview of the detection of circulating and extracted beam are given. Finally, the paper summarizes the results of these experiments together with ideas for future developments.

  5. Vibrating Wire for Beam Profile Scanning

    CERN Document Server

    Arutunian, S G; Mailian, M R; Sinenko, I G; Vasiniuk, I E

    1999-01-01

    The method for measurement of transverse profile (emittance) of the bunch by detecting of radiation arising scattering at of the bunch on the scanning wire is wide-spread. In this work the information about scattering bunch is proposed to measure using the oscillation frequency of the tightened scanning wire. In such way the system of radiation (or secondary particles) extraction and measurement can be removed. Dependence of oscillations frequency on beam scattering is determined by several factors, including changes of wire tension caused by transverse force of the beam, influence of beam self field. Preliminary calculations show that influence caused by wire heating will dominate. We have studied strain gauges on the basis of vibrating wire from various materials (tungsten, beryl bronze, niobium zirconium alloys). A scheme of self oscillations generation by alternating current in autogeneration circuit with automatic frequency adjustment was selected. Special method of wire fixation and elimination of trans...

  6. High repetition rate intense ion beam diode

    International Nuclear Information System (INIS)

    A magnetically insulated ion beam diode with a gas-breakdown plasma anode has been successfully developed recently. In this paper, the authors report the experiment results of operating a version of this diode at a 1-Hz repetition rate. Intense ion beams (100ns, 200Kv and 20kA per pulse) are generated by using an inductive voltage to breakdown an annular hydrogen gas puff (8.5cm mean radius, and 160cm2 in area), and magnetically driving the resulting plasma toward a magnetically insulated accelerating gap. The high voltage pulses on the accelerating gap are supplied using two thyratron switch chassises which are connected to the diode through a series of capacitors coupled with saturable inductors. To understand the operation of the diode, the anode plasma source and the extracted ion beams are characterized by using various diagnostics

  7. Neutralized transport of high intensity beams

    International Nuclear Information System (INIS)

    The NTX experiment at the Heavy Ion Fusion Virtual National Laboratory is exploring the performance of neutralized final focus systems for high perveance heavy ion beams. A converging ion beam at the exit of the final focus magnetic system is injected into a neutralized drift section. The neutralization is provided by a metal arc source and an RF plasma source. Effects of a ''plasma plug'', where electrons are extracted from a localized plasma in the upstream end of the drift section, and are then dragged along by the ion potential, as well as the ''volumetric plasma'', where neutralization is provided by the plasma laid down along the ion path, are both studied and their relative effects on the beam spot size are compared. Comparisons with 3-D PIC code predictions will also be presented

  8. Inner Crack Detection Method for Cantilever Beams

    Science.gov (United States)

    Li, Zheng; Zhang, Wei; Li, Yixuan; Su, Xianyue

    2008-02-01

    In this paper, continuous wavelet transform has been performed to extract the inner crack information from the guided waves in cantilever beams, and the location and size of crack can be detected exactly. Considering its best time-frequency property, Gabor continuous wavelet transform is employed to analyze the complicated flexible wave signals in cantilever beam, which is inspirited by an impact on the free end. Otherwise, in order to enhance the sensitivity of detection for some small cracks, an improved method is discussed. Here, both computational and experimental methods are carried out for comparing the influence of different crack location in beam. Therefore, the method proposed can be expected to expand to a powerful damage detection method in a broad engineering application.

  9. KEKB beam instrumentation systems

    Science.gov (United States)

    Arinaga, M.; Flanagan, J.; Hiramatsu, S.; Ieiri, T.; Ikeda, H.; Ishii, H.; Kikutani, E.; Mimashi, T.; Mitsuhashi, T.; Mizuno, H.; Mori, K.; Tejima, M.; Tobiyama, M.

    2003-02-01

    For the stable high-luminosity operation and luminosity increase, the electron and positron storage rings of the KEK B-Factory (KEKB) is equipped with various beam instrumentations, which have been working well since the start of the commissioning in December, 1998. Details and performance of the beam-position monitor system based on the spectrum analysis using DSPs, the turn-by-turn BPM with four-dimensional function available for measurements of the individual bunch position, phase and intensity, the parametric beam-DCCTs designed so as to avoid the magnetic-core-selection problems for the parametric flux modulation, the bunch-by-bunch feedback system indispensable to suppress the strong multibunch instabilities in KEKB, the various optical beam diagnostic systems, such as synchrotron radiation interferometers for precise beam-size measurement, the tune meters, the bunch length monitors and the beam-loss monitors are described. Delicate machine tuning of KEKB is strongly supported by these instrumentations.

  10. Laser Beam Focus Analyser

    DEFF Research Database (Denmark)

    Nielsen, Peter Carøe; Hansen, Hans Nørgaard; Olsen, Flemming Ove;

    2007-01-01

    The quantitative and qualitative description of laser beam characteristics is important for process implementation and optimisation. In particular, a need for quantitative characterisation of beam diameter was identified when using fibre lasers for micro manufacturing. Here the beam diameter limits...... the obtainable features in direct laser machining as well as heat affected zones in welding processes. This paper describes the development of a measuring unit capable of analysing beam shape and diameter of lasers to be used in manufacturing processes. The analyser is based on the principle of a rotating...... mechanical wire being swept through the laser beam at varying Z-heights. The reflected signal is analysed and the resulting beam profile determined. The development comprised the design of a flexible fixture capable of providing both rotation and Z-axis movement, control software including data capture...

  11. Study of Cone Beam CT in risk assessment and planning approach for extraction of impacted mandibular third molar%CBCT在下颌阻生第三磨牙拔除术前风险评估中的应用

    Institute of Scientific and Technical Information of China (English)

    黄兰柱; 王铁梅; 黄政; 盛璐; 刘澍

    2014-01-01

    Objective:To investigate the risks of inferior alveolar nerve(IAN) injury by removing impacted mandibular third molar,and difference of the surgical techniques by cone beam CT(CBCT). Method:Subjects with an increased risk of IAN injury,as diagnosed on panoramic radiographs,were enrolled in this study and underwent additional CBCT imaging. Two groups of doctors(each group contains a oralmaxillofacial surgeon and a radiologist) independently planned the surgical tech-nique and estimated the risk of IAN injury on panoramic radiographs and on CBCT images.A test of Chi-square test was exe-cuted to calculate the differences between the two imaging modalities. Result:The study sample comprised 42 patients(mean age 30.5 years) presenting 65 mandibular third molars. Risk assessment for IAN injury based on panoramic radiography compared with CBCT imaging differed significantly (P<0.001). After reviewing the CBCT images,the clinicians get the pre-cise distance and the relative relationship of the mandibular third molar and inferior alveolar canal compared with the panoramic radiograph assessments. This change in risk assessment also resulted in a significantly different surgical approach (P <0.001). Conclusion: This study show that CBCT contributes to optimal risk assessment and,as a consequence,to more adequate surgical planning,compared with panoramic radiography.%目的:运用CBCT评估下颌阻生第三磨牙拔除术中下牙槽神经损伤的手术风险,并指导拔牙手术径路选择。方法:对曲面体层片显示下颌第三磨牙根端与下颌神经管接触重叠,评估下牙槽神经易损伤病例42例,65侧下颌阻生第三磨牙,进行CBCT检查。两组医师(每组口腔外科医师和颌面影像科医师各1名)分别根据曲面体层片和CBCT图像评估拔除下颌第三磨牙时下牙槽神经损伤的风险程度并进行手术设计,应用x2检验两种影像评测结果之间的差异度。结果:评估拔除下颌阻生

  12. Proton Beam Energy Characterization

    OpenAIRE

    Marus, Lauren A.; Engle, J.W.; John, K. D.; Birnbaum, E. R.; Nortier, F. M.

    2015-01-01

    Introduction The Los Alamos Isotope Production Facility (IPF) is actively engaged in the development of isotope production technologies that can utilize its 100 MeV proton beam. Characterization of the proton beam energy and current is vital for optimizing isotope production and accurately conducting research at the IPF. Motivation In order to monitor beam intensity during research irradiations, aluminum foils are interspersed in experimental stacks. A theoretical yield of 22Na from...

  13. Hyperon beam physics

    Energy Technology Data Exchange (ETDEWEB)

    Cooper, P.S.

    1996-03-01

    This report reviews the present status and recent results in hyperon physics concentrating on results from high energy hyperon beam experiments performed at Fermilab over the past several years. The report focuses on hyperon production polarization, precision hyperon magnetic moment measurements and radiative decay studies. Modern charged hyperon beam experiments are characterized by {approx}100m long apparatus and hyperon beams with {gamma}{sub Y}{approx}100 and hyperon fluxes in the 1-100 kHz range.

  14. Chilled beam application guidebook

    CERN Document Server

    Butler, David; Gräslund, Jonas; Hogeling, Jaap; Lund Kristiansen, Erik; Reinikanen, Mika; Svensson, Gunnar

    2007-01-01

    Chilled beam systems are primarily used for cooling and ventilation in spaces, which appreciate good indoor environmental quality and individual space control. Active chilled beams are connected to the ventilation ductwork, high temperature cold water, and when desired, low temperature hot water system. Primary air supply induces room air to be recirculated through the heat exchanger of the chilled beam. In order to cool or heat the room either cold or warm water is cycled through the heat exchanger.

  15. Semiconductor laser beam bending

    OpenAIRE

    YILDIRIM, REMZİ; ÇELEBİ, FATİH VEHBİ

    2015-01-01

    This study is about a single-component cylindrical structured lens with a gradient curve that was used for bending laser beams. It operates under atmospheric conditions and bends the laser beam independently of temperature, pressure, polarity, polarization, magnetic field, electric field, radioactivity, and gravity. A single-piece cylindrical lens that can bend laser beams was developed. Lenses are made of transparent, tinted, or colored glass and are used to undermine or absorb the energy of...

  16. Mechanical beam isolator

    International Nuclear Information System (INIS)

    Back-reflections from a target, lenses, etc. can gain energy passing backwards through a laser just like the main beam gains energy passing forwards. Unless something blocks these back-reflections early in their path, they can seriously damage the laser. A Mechanical Beam Isolator is a device that blocks back-reflections early, relatively inexpensively, and without introducing aberrations to the laser beam

  17. Resolving Two Beams in Beam Splitters with a Beam Position Monitor

    Science.gov (United States)

    Kurennoy, Sergey

    2002-04-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters. Monitoring two transversely separated beams in a common beam pipe in the splitter sections imposes certain requirements on beam diagnostics for these sections. We explore a two-beam system in a generic beam monitor and study the feasibility of resolving the transverse positions of the two beams with one diagnostics device. Effects of unequal beam currents and of finite transverse sizes of the beams are explored analytically for both the ultra relativistic case and the long-wavelength limit.

  18. Beam cavity interaction

    CERN Document Server

    Gamp, A

    2011-01-01

    We begin by giving a description of the rf 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, rf feedback, and feed-forward are described. Examples of digital rf 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.

  19. Beam alignment system

    International Nuclear Information System (INIS)

    A patent is claimed for the invention of a beam alignment system. The aim of the invention is the obtention of an accurate monitoring of the beam position and direction. It is of great interest in the nuclear industry. The invention can be applied in an infrared laser beam for welding operations. An auxiliar radiation source is incorporated to the device. The system's configuration allows a simultaneous and separated utilisation of two beams. The description and the design of the proposed system are provided

  20. Simulation of Beam-Beam Background at CLIC

    CERN Document Server

    Sailer, A

    2010-01-01

    The dense beams used at CLIC to achieve a high luminosity will cause a large amount of background particles through beam-beam interactions. Generator level studies with GUINEAPIG and full detector simulation studies with an ILD based CLIC detector have been performed to evaluate the amount of beam-beam back- ground hitting the vertex detector.

  1. A hydrogen ion beam method of molecular density measurement inside a 4.2-K beam tube

    International Nuclear Information System (INIS)

    In our first experiments on synchrotron radiation-induced photodesorption in a 4.2-K beam tube, the moleculm density was measured by room temperature ion gauges and RGAs outside the beam tube. The molecular density inside the 4.2-K beam tube was therefore unknown, since the mean molecular speed of photodesorbed molecules had not been measured. To determine the density inside the 4.2-K beam tube we have developed a direct method of measurement utilizing the neutralization of H+ beams, which are proportional to gas density. The hydrogen ion beams (up to 20 keV, ∼1 μA) are extracted from an rf ion source and guided into the cold beam tube by a bending magnet. The H0 and H- produced in the beam tube are magnetically separated from H- and detected with secondary electron multipliers (SEMs). Small superconducting dipole magnets located near the center of the beam tube allow a ∼20-cm segment of the injected ion beam to be offset a few mm from the injection axis; detection of H0 and H- produced along this offset segment provides a localized density measurement. If necessary, detector background due to synchrotron radiation photons can be discriminated against by gating the detector on between the bursts of synchrotron radiation. The experimental setup and initial data will be presented

  2. A hydrogen ion beam method of molecular density measurement inside a 4.2-K beam tube

    Energy Technology Data Exchange (ETDEWEB)

    Alinovsky, N.; Anashin, V.; Beschasny, P. [Budker Inst. of Nuclear Physics, Novosibirsk (Russian Federation)] [and others

    1994-06-01

    In our first experiments on synchrotron radiation-induced photodesorption in a 4.2-K beam tube, the moleculm density was measured by room temperature ion gauges and RGAs outside the beam tube. The molecular density inside the 4.2-K beam tube was therefore unknown, since the mean molecular speed of photodesorbed molecules had not been measured. To determine the density inside the 4.2-K beam tube we have developed a direct method of measurement utilizing the neutralization of H{sup +} beams, which are proportional to gas density. The hydrogen ion beams (up to 20 keV, {approximately}1 {mu}A) are extracted from an rf ion source and guided into the cold beam tube by a bending magnet. The H{sup 0} and H{sup {minus}} produced in the beam tube are magnetically separated from H{sup {minus}} and detected with secondary electron multipliers (SEMs). Small superconducting dipole magnets located near the center of the beam tube allow a {approximately}20-cm segment of the injected ion beam to be offset a few mm from the injection axis; detection of H{sup 0} and H{sup {minus}} produced along this offset segment provides a localized density measurement. If necessary, detector background due to synchrotron radiation photons can be discriminated against by gating the detector on between the bursts of synchrotron radiation. The experimental setup and initial data will be presented.

  3. Ion beam emittance from an ECRIS

    Energy Technology Data Exchange (ETDEWEB)

    Spädtke, P., E-mail: p.spaedtke@gsi.de; Lang, R.; Mäder, J.; Maimone, F.; Schlei, B. R.; Tinschert, K. [Gesellschaft für Schwerionenforschung (GSI), Darmstadt (Germany); Biri, S.; Rácz, R. [MTA Atomki, Debrecen (Hungary)

    2016-02-15

    Simulation of ion beam extraction from an Electron Cyclotron Resonance Ion Source (ECRIS) is a fully 3 dimensional problem, even if the extraction geometry has cylindrical symmetry. Because of the strong magnetic flux density, not only the electrons are magnetized but also the Larmor radius of ions is much smaller than the geometrical dimension of the plasma chamber (Ø 64 × 179 mm). If we assume that the influence of collisions is small on the path of particles, we can do particle tracking through the plasma if the initial coordinates of particles are known. We generated starting coordinates of plasma ions by simulation of the plasma electrons, accelerated stochastically by the 14.5 GHz radio frequency power fed to the plasma. With that we were able to investigate the influence of different electron energies on the extracted beam. Using these assumptions, we can reproduce the experimental results obtained 10 years ago, where we monitored the beam profile with the help of viewing targets. Additionally, methods have been developed to investigate arbitrary 2D cuts of the 6D phase space. To this date, we are able to discuss full 4D information. Currently, we extend our analysis tool towards 5D and 6D, respectively.

  4. Random coincidences during in-beam PET measurements at microbunched therapeutic ion beams

    Science.gov (United States)

    Parodi, K.; Crespo, P.; Eickhoff, H.; Haberer, T.; Pawelke, J.; Schardt, D.; Enghardt, W.

    2005-06-01

    At the experimental carbon ion tumour therapy facility at GSI Darmstadt, in-beam positron emission tomography (PET) is used to monitor the dose delivery precision. A dual head positron camera has been assembled from commercial detector components in order to measure the β+-activity, induced by the irradiation, simultaneously to the dose application. Despite the positive clinical impact, the image quality is limited by the low counting statistics, orders of magnitude below that in standard PET applications to nuclear medicine. This paper investigates the origin for the noisy acquisition during particle extraction from the synchrotron of GSI. The results demonstrate the failure of standard random correction techniques due to a γ-ray background correlated in time with the carbon ion beam microstructure. This prevents the use of data acquired during beam extraction for imaging. The loss of counting statistics is expected to rise further at the future hospital-based facility at Heidelberg, due to a more efficient utilisation of the accelerator resulting in shorter beam pauses and a reduced treatment time. In this respect, this paper provides the basis for a new data acquisition concept tailored to the unconventional application of in-beam PET imaging to therapy monitoring at radiofrequency pulsed radiation sources.

  5. Resolving Two Beams in Beam Splitters with a Beam Position Monitor

    CERN Document Server

    Kurennoy, S S

    2002-01-01

    The beam transport system for the Advanced Hydrotest Facility (AHF) anticipates multiple beam splitters [1]. Monitoring two separated beams in a common beam pipe in the splitter sections imposes certain requirements on diagnostics for these sections. In this note we explore a two-beam system in a generic beam monitor and study the feasibility of resolving the positions of the two beams with a single diagnostic device.

  6. Damping of a vibrating beam

    NARCIS (Netherlands)

    Hietanen, Jarmo; Bomer, Johan; Jonsmann, Jacques; Olthuis, Wouter; Bergveld, Piet; Kaski, Kimmo

    2000-01-01

    This study examines the vibration in a beam with one fixed end. The set-up consisted of a beam with one end clamped and a rigid plate having the same thickness of the beam, located adjacent to the unfixed end of the beam. The gap between the beam and the plate varied from 4 to 128 μm depending on th

  7. Generation of compensated ion beams from source with oscillating electrons

    CERN Document Server

    Borisko, V N; Yunakov, N N

    2000-01-01

    The generation of compensated ion beams from electrically unsymmetrical reflecting discharge was investigated.The spatial location of a compensation zone,the optimal values of operating gas pressures P=(0.8/1) centre dot 10 sup - sup 4 Torr and potential difference between cathodes DELTA U = 80B were determined.The way to control the current compensation degree of the extracted ion beam a several to 100% was found.

  8. Beam distribution reconstruction simulation for electron beam probe

    CERN Document Server

    Feng, Yongchun; Li, Peng; Kang, Xincai; Yin, Yan; Liu, Tong; You, Yaoyao; Chen, Yucong; Zhao, Tiecheng; Xu, Zhiguo; Wang, Yanyu; Yuan, Youjin

    2016-01-01

    Electron beam probe (EBP) is a new principle detector, which makes use of a low-intensity and low-energy electron beam to measure the transverse profile, bunch shape, beam neutralization and beam wake field of an intense beam with small dimensions. While can be applied to many aspects, we limit our analysis to beam distribution reconstruction. This kind of detector is almost non-interceptive for all of the beam and does not disturb the machine environment. In this paper, we present the theoretical aspects behind this technique for beam distribution measurement and some simulation results of the detector involved. First, a method to obtain parallel electron beam is introduced and a simulation code is developed. And then, EBP as a profile monitor for dense beam is simulated using fast scan method under various target beam profile, such as KV distribution, waterbag distribution, parabolic distribution, Gaussian distribution and halo distribution. Profile reconstruction from the deflected electron beam trajectory...

  9. Linearizing Intra-Train Beam-Beam Deflection Feedback

    International Nuclear Information System (INIS)

    Beam-beam deflection feedback acting within the crossing time of a single bunch train may be needed to keep linear collider beams colliding at high luminosity. In a short-pulse machine such as the Next Linear Collider (NLC) this feedback must converge quickly to be useful. The non-linear nature of beam-beam deflection vs. beam-beam offset in these machines precludes obtaining both rapid convergence and a stable steady-state lock to beam offsets with a linear feedback algorithm. We show that a simply realizable programmable non-linear amplifier in the feedback loop can linearize the feedback loop, approximately compensating the beam-beam deflection non-linearity. Performance of a prototype non-linear amplifier is shown. Improvement of convergence and stability of the beam-beam feedback loop is simulated

  10. Beaming teaching application

    DEFF Research Database (Denmark)

    Markovic, Milos; Madsen, Esben; Olesen, Søren Krarup;

    2012-01-01

    BEAMING is a telepresence research project aiming at providing a multimodal interaction between two or more participants located at distant locations. One of the BEAMING applications allows a distant teacher to give a xylophone playing lecture to the students. Therefore, rendering of the xylophon...

  11. Ionization beam scanner

    CERN Multimedia

    CERN PhotoLab

    1973-01-01

    Inner structure of an ionization beam scanner, a rather intricate piece of apparatus which permits one to measure the density distribution of the proton beam passing through it. On the outside of the tank wall there is the coil for the longitudinal magnetic field, on the inside, one can see the arrangement of electrodes creating a highly homogeneous transverse electric field.

  12. 锥形束CT在下颌阻生第三磨牙拔除术前诊断应用的初步研究%Pilot clinical study of the dental cone beam CT examination before the impacted mandibular third molar extraction

    Institute of Scientific and Technical Information of China (English)

    陈全; 张晓; 张刚; 马绪臣

    2011-01-01

    Objective To evaluate the diagnostic accuracy of the cone beam computed tomography(CBCT)in judging the relationship between the impacted mandibular third molar(IMTM)and the inferior alveolar canal(IAC).Methods Sixty IMTM superimposing on the canal partially or touching the canal in line on panoramic radiograms were examined by CBCT. All CBCT images of these cases were observed by two dentists respectively. Then, all these IMTM were extracted by minimally invasive surgery, and the conditions of the IMTM sockets were observed. Two dentists observed the CBCT images independently and reached a consensus. Diagnosis test was performed in this study. Results Eight IMTM sockets were bleeding during the extracted operation, and whether the IAC wall was broken could not be judged. The other 52 IMTM sockets were clear and the walls of IAC were broken in 29 IMTM extractions. The sensitivity, specificity, Youden index, positive predictive value and negative predictive value of CBCT were 82.8%, 87.0%, 88.9% and 80.0% respectively. The diagnostic accuracy judged by the two dentists and Kappa coefficient were calculated as 84.6% and 0.800. Conclusions The CBCT examination had good authenticity and reliability, and it was very helpful in predicting the actual relationship between the IMTM and IAC.%目的 评价口腔颌面锥形束CT(cone beam CT,CBCT)确定下颌阻生第三磨牙(impacted mandibular third molar,IMTM)与下牙槽神经管位置关系,为IMTM拔除术中预防下牙槽神经损伤提供临床依据.方法 通过IMTM拔除术前曲面体层X线片检查,筛选出IMTM与下牙槽神经管存在较大范围接触或部分重叠影像表现的49例患者(60侧),进一步行CBCT检查,结合种植机微动力系统微创拔牙术中观察结果,应用诊断试验的方法评价术前CBCT检查结果的准确性.结果 术前CBCT观察IMTM突破下牙槽神经管壁判断的灵敏度82.8%、特异度87.0%,Youden指数0.69,阳性预测值88.9%,阴性预测值80.0%.两位

  13. Mechanically reinforced glass beams

    DEFF Research Database (Denmark)

    Nielsen, Jens Henrik; Olesen, John Forbes

    2007-01-01

    The use of glass as a load carrying material in structural elements is rarely seen even though glass is a popular material for many architects. This is owed to the unreliable and low tensile strength, which is due to surface flaws and high brittleness of the material. These properties lead...... to breakage without any warning or ductility, which can be catastrophic if no precautions are taken. One aspect of this issue is treated here by looking at the possibility of mechanically reinforcing glass beams in order to obtain ductile failure for such a structural component. A mechanically reinforced...... laminated float glass beam is constructed and tested in four-point bending. The beam consist of 4 layers of glass laminated together with a slack steel band glued onto the bottom face of the beam. The glass parts of the tested beams are \\SI{1700}{mm} long and \\SI{100}{mm} high, and the total width of one...

  14. Beam director design report

    Energy Technology Data Exchange (ETDEWEB)

    Younger, F.C.

    1986-08-01

    A design and fabrication effort for a beam director is documented. The conceptual design provides for the beam to pass first through a bending and focusing system (or ''achromat''), through a second achromat, through an air-to-vacuum interface (the ''beam window''), and finally through the vernier steering system. Following an initial concept study for a beam director, a prototype permanent magnet 30/sup 0/ beam-bending achromat and prototype vernier steering magnet were designed and built. In volume II, copies are included of the funding instruments, requests for quotations, purchase orders, a complete set of as-built drawings, magnetic measurement reports, the concept design report, and the final report on the design and fabrication project. (LEW)

  15. Beam director design report

    International Nuclear Information System (INIS)

    A design and fabrication effort for a beam director is documented. The conceptual design provides for the beam to pass first through a bending and focusing system (or ''achromat''), through a second achromat, through an air-to-vacuum interface (the ''beam window''), and finally through the vernier steering system. Following an initial concept study for a beam director, a prototype permanent magnet 300 beam-bending achromat and prototype vernier steering magnet were designed and built. In volume II, copies are included of the funding instruments, requests for quotations, purchase orders, a complete set of as-built drawings, magnetic measurement reports, the concept design report, and the final report on the design and fabrication project

  16. Muon Beam at the Fermilab Test Beam Area

    OpenAIRE

    Denisov, Dmitri; Evdokimov, Valery; Lukić, Strahinja; Ujić, Predrag

    2016-01-01

    The intensities and profiles of the muon beam behind the beam dump of the Fermilab test beam area when the facility is running in the "pion" beam mode are measured and summarized in this note. This muon beam with momenta in the range 10 - 50 GeV/c provides an opportunity to perform various measurements in parallel with other users of the test beam area.

  17. Current performance of the self-extracting cyclotron

    International Nuclear Information System (INIS)

    The self-extracting cyclotron is a 14MeV multi-mA H+ machine from which the beam extracts without a deflector. The development of this prototype has started in 1998, and has now reached a point such that IBA considers to use it as a production machine. It is now installed in an irradiation facility and is equipped with two beam lines and two high power target-system. Beams of more than 1 mA have been extracted and transported to targets Further development is ongoing in order to increase the current on target to at least 2 mA in the coming months. Commercial isotope production will start at the end of this year. This paper will describe the current configuration of the cyclotron and the associated performances. Emphases will be put on reliability and associated problems, beam optics and performances of sub-systems

  18. Diffraction of a Laser Beam.

    Science.gov (United States)

    Jodoin, Ronald E.

    1979-01-01

    Investigates the effect of the nonuniform irradiance across a laser beam on diffraction of the beam, specifically the Fraunhofer diffraction of a laser beam with a Gaussian irradiance profile as it passes through a circular aperture. (GA)

  19. MULTIPLE SINGLE BUNCH EXTRACTION TO THE AGS SWITCHYARD

    International Nuclear Information System (INIS)

    In this report we will describe the multiple single bunch extraction system as utilized to deliver beams to the Brookhaven's Alternating Gradient Synchrotron (AGS) switchyard area. We will describe modifications of the AGS switchyard, necessary to allow it to accept bunched beam, and results of the first commissioning of this system. The AGS Switchyard has for many years been used to simultaneously deliver (unbunched) resonant extracted beam to a set of fixed target experiments. In order to accommodate new fixed target experiments which require bunched beams, a method of sending the bunched beams to the AGS Switchyard was required. In addition, by using the AGS switchyard instead of the upstream section of the Brookhaven's Relativistic Heavy Ion Collider (RHIC) injection line the accelerators can be reconfigured quickly and efficiently for filling RHIC. We will present results of the commissioning of this system, which was done in January 2001

  20. Commissioning of heating neutral beams for COMPASS-D tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Deichuli, P.; Davydenko, V.; Belov, V.; Gorbovsky, A.; Dranichnikov, A.; Ivanov, A.; Sorokin, A.; Mishagin, V.; Abdrashitov, A.; Kolmogorov, V.; Kondakov, A. [Budker Institute of Nuclear Physics, 630090 Novosibirsk (Russian Federation)

    2012-02-15

    Two neutral beam injectors have been developed for plasma heating on COMPASS-D tokamak (Institute of Plasma Physics, Prague). The 4-electrodes multihole ion-optical system with beam focusing was chosen to provide the low divergence 300 kW power in both deuterium and hydrogen atoms. The accelerating voltage is 40 kV at extracted ion current up to 15 A. The power supply system provides the continuous and modulated mode of the beam injection at a maximal pulse length 300 ms. The optimal arrangement of the cryopanels and the beam duct elements provides sufficiently short-length beamline which reduces the beam losses. The evolution of the impurities and molecular fraction content is studied in the process of the high voltage conditioning of the newly made ion sources. Two injectors of the same type have been successfully tested and are ready for operation at tokamak in IPP, Prague.