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electron

             
Paper Title Other Keywords Page
MOYMA01 Overview of Energy-Recovery Linacs linac, emittance, radiation, laser 11
 
  • R. Hajima
    JAEA/ERL, Ibaraki
  An energy-recovery linac (ERL) is capable of generating an electron beam of high-brightness and high average current. It is, thus, a promising device for future light sources such as next-generation X-ray sources and high-power FELs, and several projects are under way in the world. In this talk, we overview the current status of these projects. Recent studies on beam dynamics issues and development of key components for the ERLs are also presented.  
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MOOPMA05 R&D on Vacuum Components for High-Current Accelerators vacuum, positron, impedance, radiation 41
 
  • Y. Suetsugu, H. Hisamatsu, K.-I. Kanazawa, K. Shibata, M. Shirai
    KEK, Ibaraki
  In anticipation of coming high current accelerators era, R&D on various vacuum components has been carried out at KEK. Copper beam ducts with ante-chambers were designed to deal with the intense synchrotron radiation (SR) power density emitted from the high current beam. The ante-chamber structure is also effective to reduce photoelectrons around positron beam, which is helpful to suppress the electron cloud instability (ECI). A comb-type RF-shield was developed to reduce the beam impedance and improve the thermal strength compared to the conventional finger-type one, and applied to bellows chambers and gate valves. The connection flange with the same cross section to the beam duct was also developed in parallel. Novel structure of a movable mask (collimator) was recently proposed, which had lower impedance compared to the conventional one, and now the test model was under fabrication. The beam ducts, the bellows chambers, and the gate valves have been installed in the KEK B-factory (KEKB) positron ring for several years. The performance of these components has been studied during beam operation, and the promising results have been obtained.  
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TUXMA03 Next Generation Electron-Ion Colliders ion, luminosity, collider, proton 56
 
  • I. Ben-Zvi
    BNL, Upton, Long Island, New York
  The next generation of electron-ion colliders is expected to deliver much higher luminosity, a high degree of polarization of both the leptons and hadrons, multiple interaction points and large ratios of beam energies as compared to the first end only such collider, HERA. Energy Recovery Linacs (ERLs) have significant potential uses as providers of lepton beams for colliders in High Energy Physics and Nuclear Physics. We describe plans for these colliders which are under development by various laboratories and the technology issues that are associated with these applications. The advantages of ERLs for these applications are numerous and will be outlined in the text. It is worth noting that some of these advantages are the high-brightness of the ERL beams and their relative immunity to beam-beam disturbances.  
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TUZMA01 RHIC Status luminosity, polarization, proton, ion 74
 
  • T. Roser
    BNL, Upton, Long Island, New York
  As the first hadron accelerator and collider consisting of two independent superconducting rings RHIC has operated with a wide range of beam energies and particle species. Machine operation and performance will be reviewed that includes high luminosity gold-on-gold and copper-on-copper collisions at design beam energy (100 GeV/u), asymmetric deuteron-on-gold collisions as well as high energy polarized proton-proton collisions (100 GeV on 100 GeV) with beam polarization of up to 65%. Plans for future upgrades of RHIC will also be discussed.  
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TUZH102 Ion Instability Issues in Electron Rings ion, vacuum, undulator, damping 79
 
  • T.-Y. Lee, J. Choi, H.-S. Kang
    PAL, Pohang, Kyungbuk
  The fast ion instability (FII) attracts interests recently for the International Linear Collider Project. FII was found by simulation in SLAC and later observed experimentally. Brief introduction and history of FII is given in this talk and a recent observation of FII in the PLS in-vacuum undulator is reported.  
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TUZH103 Electron Cloud Experiments, Simulation and Cure simulation, feedback, quadrupole, dipole 89
 
  • H. Fukuma
    KEK, Ibaraki
  A large number of electrons called electron clouds have been observed both in positron and hadron accelerators. Possible sources of the electron clouds are photoelectrons generated by synchrotron radiation, electrons produced by beam hitting vacuum components, electrons multiplied by beam induced multipacting, electrons created by ionization of residual gasses and so on. The electron clouds produce various effects such as pressure rise, heat load on a cold chamber wall, beam induced multipacting, betatron tune shifts, coupled bunch instability and beam size blow-up which often limit the performance of the accelerators. Many experimental and theoretical studies on the electron clouds have been carried out and their results have contributed to the improvement of performance of existing accelerators and design of future accelerators. This talk reviews experiments, simulations and cures of the electron cloud effects in positron and hadron accelerators.  
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TUC3MA03 Ultimate Abilities of Conventional Positron Sources positron, target, linac, acceleration 97
 
  • P. V. Logachev, M. S. Avilov, M. B. Blinov, P. Martyshkin, T. A. Vsevolozhskaya
    BINP SB RAS, Novosibirsk
  Significant increasing of desired luminosity for future e+e- colliders leads to corresponding enlargement of positron production rate. Conventional technology of positron production have not reached yet its technical limits. Experimental study in order to find out these limits for basic subsystems of positron source is presented in this paper.  
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TUPMA005 Simulation Study on Bunch Lengthening storage-ring, single-bunch, damping, synchrotron 106
 
  • Y. Sun, Z. Y. Guo
    PKU/IHIP, Beijing
  • J. Gao
    IHEP Beijing, Beijing
  The bunch lengthening phenomenon is resulted from one of the most severe single bunch instabilities in electron storage rings. As for BEPCII, controlling the bunch length is the most critical task to fulfil the designed luminosity goal. A new code is developed to calculate the single bunch length and energy spread in storage rings using FORTRAN. In this code, the wake field is calculated using an analytical formula. The bunch length and energy spread under different bunch current are calculated for BEPCII. The tracking results clearly show that the microwave instability threshold is around 65 mA for BEPCII storage ring. The tracking results of this code are in good accordance with those from other codes.  
 
TUPMA012 Measurement of Bremsstrahlung Dependent on Stored Beam Current vacuum, storage-ring, radiation, ion 115
 
  • Y. Yamamoto
    Ritsumeikan University, Kusatsu-City, Shiga
  Bremsstrahlung was measured as a function of stored beam current using the BGO scintillation spectrometer at the compact superconducting storage ring of Ritsumeikan University. Bremsstrahlung is emitted for collision of stored electrons and residual gas on the beam orbit. Yield of bremsstrahlung depend on stored beam current and residual gas density. We tried to determine gas density on the beam orbit by present measurement.  
 
TUPMA031 Development of Trigger and Clock Delay Module with Ultra-wide Range and High Precision laser, controls, synchrotron, insertion 145
 
  • T. Ohshima, Y. Fukuyama, J. Kim
    JASRI/SPring-8, Hyogo-ken
  • E. Nonoshita, H. Sengoku
    Candox Systems Inc., Gyoda city, Saitama perfecture
  • Y. T. Tanaka
    RIKEN Spring-8 Harima, Hyogo
  Pump and probe experiments using pulse lasers and synchrotron radiation require precise timing relation between the laser pulse and the RF signal of the accelerator. The pulse laser needs clock signal for a mode-locked oscillator and trigger signal to a regenerative oscillator. The delay time of these two signals were usually adjusted by using a mechanical phase shifter or a cable delay. They have disadvantages of short tuning range or discontinuity in the clock signal. We developed a new delay module, which can continuously change the delay time with the range of ±1 s and the precision better than 5 ps. The key point of the module is combination of an IQ modulator and a synchronous counter. The IQ modulator can change the phase of the RF signal with infinite amount with high precision in both plus and minus direction, which is used to produce the laser clock. The phase-modulated RF signal is also fed to the synchronous counter and its output is used to the trigger of the regenerative oscillator. The effectiveness of this module was confirmed by an experiment carried out at the SPring-8. Detail composition of the module, its application and performance are described in the paper.  
 
TUPMA035 SCSS Prototype Accelerator Timing System controls, acceleration, gun, klystron 154
 
  • N. Hosoda, T. Ohata, T. Ohshima
    JASRI/SPring-8, Hyogo-ken
  • H. Maesaka, Y. Otake
    RIKEN Spring-8 Harima, Hyogo
  SPring-8 Compact SASE-FEL Source (SCSS) project is in progress. To verify its feasibility, the 250MeV SCSS prototype accelerator (SPA) was constructed and beam commissioning started in October 2005. We observed first lazing of 49nm wave length in June 2006. In this paper, we describe the timing system of SPA. The target time jitter was selected under 1ps. To achieve this, A master trigger generator unit (MTU), a master trigger distribution unit, a 5712MHz synchronous trigger delay unit (TDU) and a level converter unit were newly developed. The MTU generates a 1-120Hz master trigger to drive all accelerator components synchronously from 60Hz AC line and 238MHz RF. The TDU is an 8ch 24bit delay counter to generate required timing signals for each component using the master trigger from the MTU. The TDU uses 238MHz RF as a counter clock and uses 5712MHz RF to recover the circuit jitter and to synchronize to the electron beam. The time jitter of 0.71ps in the TDU was achieved. We measured the time jitter between an electron beam and a 5712MHz RF that is a main acceleration RF frequency, and obtained 0.34ps. This demonstrates good stability of SPA.  
 
TUPMA036 Comparative Studies of Electron Sources for a Free Electron Laser at PSI emittance, gun, cathode, space-charge 157
 
  • M. Dehler, A. Anghel
    PSI, Villigen
  Within the low emittance gun project LEG, the Paul Scherrer is currently conducting research into the development of a high brightness electron source suitable for free electron laser. The gun, planned to generate up to 5.5 Amperes of beam current, consists of a pulsed DC diode followed by a 1 1/2 cell RF gun. Using specialized codes, the performance of field emitter arrays is evaluated assuming realistic geometries. As alternatives, we examine the performance of using individual macroscopic field emission tips or conventional photo emission using copper cathodes. For these, optimized cathode geometries are presented and the performance is compared to that of field emitter arrays.  
 
TUPMA037 Project of Infrared Storage Ring Free Electron Lasers at AIST undulator, storage-ring, free-electron-laser, klystron 160
 
  • N. Sei, H. Ogawa, K. Y. Yamada, M. Y. Yasumoto
    AIST, Tsukuba, Ibaraki
  Development of free electron lasers (FELs) with a compact storage ring NIJI-IV in the near and middle infrared regions is planned in National Institute of Advanced Industrial Science and Technology (AIST). Infrared FELs with a linear accelerator have already been developed and used for various applications in many FEL facilities. However, there is no storage ring FEL (SRFEL) which can oscillate in those regions widely. Although an SRFEL is inferior to a linear accelerator FEL in the average power, it has an extremely stable wavelength and its line width is as narrow as that of a monochromatic light in a synchrotron radiation facility. The average power of the synchrotron radiation in an infrared beam line is about 10 micro-watt at most. Then the SRFEL can be expected as a light source which is more intense than the synchrotron radiation. The output power which is our target is 1 mill-watt. We are aiming at SRFEL oscillations in a wavelength region from 1 to 10 micron which include the fingerprint region partly.

sei.n@aist.go.jp

 
 
TUPMA038 Start-up of an FEL Oscillator from Shot Noise radiation, simulation, undulator, free-electron-laser 163
 
  • V. Kumar, S. Krishnagopal
    RRCAT, Indore (M. P.)
  • W. M. Fawley
    LBNL, Berkeley, California
  In free-electron laser (FEL) oscillators, as in self-amplified spontaneous emission (SASE) FELs, the build-up of intra-cavity power starts from shot noise resulting from the discreteness of charge in the electron bunch. It is important to do the start-up analysis for the build-up of intracavity power in order to fix the macropulse width from the electron accelerator such that the system reaches saturation. In this paper, we show that one can use the time-dependent oscillator code GINGER [1] to perform this anlysis. we present results of this analysis for the parameters of the Compact Ultrafast TErahertz FEL (CUTE-FEL) [2] being built at RRCAT.

1. W. Fawley, 'A user Manual for GINGER and Its Post-Processor XPLOTGIN}},LBNL-49625-Rev. I' ed., Lawrence Berkley National Laboratory (2004).2. S. Krishnagopal et al., Proceedings of FEL conference (2006) 496.

 
 
TUPMA039 Comparison of Codes for Smith-Purcell FEL simulation, free-electron-laser, plasma, laser 166
 
  • V. Kumar
    RRCAT, Indore (M. P.)
  • K.-J. Kim
    ANL, Argonne, Illinois
  • D. Li
    ILT, Suita, Osaka
  Smith-Purcell FELs using low energy electron beam are being seen as attractive option for a compact source of coherent Terahertz ratiation. Recently, Kumar and Kim [1] have performed numerical simulation of Smith-Purcell free-electron lasers (SP-FELs) based on a computer code using Maxwell-Lorent equations. Li et al. [2], and Dounhue et al. [3] have performed calculations using PIC codes. In this paper, we present a comparision of these methods and compare results obtained using different codes.

1. V. Kumar et al., Phys. Rev. E 73, 026501 (2006). 2. D. Li et al., Phys. Rev. ST Accel. Beams 9, 040701 (2006). 3. J. T. Donohue et al., Phys. Rev. ST Accel. Beams 9, 060701 (2006).

 
 
TUPMA042 Beam Parameters of the SCSS Prototype Accelerator Designed by PARMELA and Comparison with Measured Values emittance, gun, simulation, cathode 169
 
  • T. Hara, H. Kitamura, T. Shintake, K. Togawa
    RIKEN Spring-8 Harima, Hyogo
  • H. Tanaka
    JASRI/SPring-8, Hyogo-ken
  • T. Tanikawa
    University of Hyogo, Hyogo
  The 250 MeV prototype facility of the SCSS X-FEL project was constructed in the Octorber 2005 and the machine commissioning was started in May 2006. One month later, we have succeeded in confirming the amplification of the synchrotron radiation. The electron beam parameters, such as peak current and emittance, have been designed and estimated using PARMELA. In contrast to other X-FEL projects, the SCSS injector uses a thermionic pulsed electron gun [1]. Compared with RF photocathode guns, the thermionic gun is stable and easy to handle. Its peak current, however, is smaller, and the compression of the electron bunch is necessary at early stage of the low beam energy injector. In this report, we compare the simulation and measured values, such as a bunch length and projected emittance, on the SCSS prototype accelerator. The measured beam parameters, after the bunch compression procedure and emittance degradation due to space charge, show fairly good agreement with the simulation.

[1] K. Togawa, et al., “Emittance Measurement on the CeB6 Electron Gun for the SPring-8 Compact SASE Source”, Proceedings of the 2004 FEL Conference, (2004)351-354, URL: http://www. JACoW.org.

 
 
TUPMA047 Development of a Photocathode DC Gun at JAEA-ERL gun, emittance, cathode, laser 175
 
  • R. Hajima, H. Iijima, R. Nagai, N. Nishimori, T. Nishitani
    JAEA/ERL, Ibaraki
  An electron gun producing an e-beam with high-brightness and high average-current is a key component to realize a next-generation X-ray light source based on energy-recovery linac (ERL). In JAEA, we are developing a photocathode DC gun for a future ERL light source. The DC gun is operated at 250 kV and 50 mA at maximum, and equipped with a load-lock chamber for cathode preparation. In order to keep small emittance at high current operation, we adopt superlattice semiconductor as a photocathode. In this paper, we present the status of the gun development and future plans towards the ERL test facility to construct in collaboration with KEK.  
 
TUPMA052 Study on Compact DC Electron Gun using Single Crystal Cathode of LaB6 cathode, gun, emittance, simulation 181
 
  • K. Kasamsook, K. Akiyama, H. Hama, F. Hinode, M. Kawai, T. Muto, K. Nanbu, T. Tanaka, M. Yasuda
    Tohoku University, School of Scinece, Sendai
  A novel, compact DC gun has been designed and is currently on a test bed at LNS. Applying 50 kV high voltage for the gun, it is expected to supply a high brightness beam of which the beam current of 300 mA and the variable pulse duration from 1 to 5 ?sec. In addition, a floating bias voltage can be applied between the cathode and the wehnelt to manipulate electric field near cathode surface. In order to produce lower emittance beam, the thermionic cathode should have very much higher current density and the size of that should be very small. Consequently we have chosen single crystal LaB6 as the thermionic cathode, which can provide higher current density with good homogeneity electron emission. The design parameters and initial operating experience of the DC gun are discussed. This DC gun will be used for free electron lasers such as backward-wave oscillator, advanced accelerator researches and other experiments. Results of numerical calculations show good distribution of macroparticles in the phase space, which results from optimization of the bias voltage. A normalized rms emittance at the exit of the gun is expected to be less than 1 ? mm mrad.  
 
TUPMA057 Physics Design of PAL-XFEL Undulator undulator, radiation, linac, vacuum 190
 
  • D. E. Kim, C. W. Chung, J.-S. Oh, K.-H. Park
    PAL, Pohang, Kyungbuk
  • I. S. Ko
    POSTECH, Pohang, Kyungbuk
  Pohang Accelerator Laboratory(PAL) is planning a 0.3 nm – 0.45 nm SASE (Self Amplification of Spontaneous Emission) XFEL based on 3.7 GeV linear accelerator. It is targeting utilization of 0.1 nm X-ray radiation using the 3rd harmonic FEL radiation. With 3.7 GeV electron beam energy, achieving 0.3 nm fundamental FEL lazing is very challenging and it requires very low emittance electron beam with minimum energy spread. It also requires small period undulator with very small gap. In this context, application of SPring8 type in vacuum undulator is seriously considered. This reflects the experiences from SPring8 SCSS project. In this report, the physics design efforts of the undulator is described. The periodic parts are optimized to achieve the highest field with other requirements. The end structures were designed to be asymmetric along the beam direction to ensure systematic zero 1st field integral. The thickness of the last magnets were adjusted to minimize the transition distance to the fully developed periodic field. The final design features 4 mm minimum pole gap, 15 mm period, peak effective field of 1.09 Tesla.  
 
TUPMA060 A Hamiltonian for Wave Length Shifter and its Studies on INDUS-1 injection, quadrupole, dynamic-aperture, betatron 199
 
  • A. A. Fakhri, G. Singh
    RRCAT, Indore (M. P.)
  The INDUS-1 is a 450 MeV synchrotron radiation source for the production of VUV radiation. In order to produce the radiation of shorter wavelengths(lc = 31 Ao), a superconducting wavelength shifter (WLS) with peak fieldof 3T is being considered for Indus-1. In this paper, L. Smith's Hamiltonian for Halbach's magnetic field model has been re-derived to estimate focussing component under the compensated electron beam trajectory transformation. Various linear compensation schemes are presented to minimize the linear effects of the WLS and its effects on machine operation are also theoretically studied.  
 
TUPMA064 ILC Activity at JINR and Siting in Dubna Region power-supply, linear-collider, collider, luminosity 202
 
  • G. V. Trubnikov, Yu. N. Denisov, I. N. Meshkov, G. Shirkov, A. N. Sissakian
    JINR, Dubna, Moscow Region
  JINR actively participates in ILC project. JINR physicists are planning to take part in several fields of activity in ILC: works on photo injector prototype, participation in design and construction of cryomodules, laser metrology, etc. Moreover Joint Institute is full-member pretender for possible hosting of ILC in the region near Dubna. International intergovernmental status of JINR, comfortable location of site, well developed infrastructure, geological, climate and relief conditions may become powerful advantages of Dubna siting among other proposals of ILC location. All above mentioned topics are discussed in the presented report.  
 
TUPMA067 New Timing System for the L-band Linear Accelerator at Osaka University linac, laser, gun, single-bunch 208
 
  • S. Kashiwagi, G. Isoyama, R. Kato, S. Suemine
    ISIR, Osaka
  • T. Asaka, Y. Kawashima
    JASRI/SPring-8, Hyogo-ken
  A highly precise and flexible timing system has been developed for the L-band linac at ISIR, Osaka University. It provides four RF signals and several timing signals for operation of the linac and for experiments with the linac. In order to realize long-term stability of the timing system and hence operation of the linac, a rubidium atomic clock producing a 10 MHz RF signal with the fractional stability of 10-15 is used as a time base for a synthesizer used as a master oscillator for generating the acceleration frequency of 1.3 GHz. The 1.3 GHz signal from the master oscillator is directly counted to produce the four RF signals and the clock signal of the timing system at 27 MHz. The master timing signals for linac operation is taken from the AC line frequency and it is synchronized with the 27MHz clock signal precisely. To make an arbitrary delayed timing signal, a standard digital delay generator is used to make a gate signal for a GaAs RF switch, with which one of the 27MHz clock pulses is sliced out to generate the delay timing signal. Any timing signal can be made in an interval of 37 ns and the timing jitter of the delayed signal is achieved to be as short as 2 ps.  
 
TUPMA075 Status of the CTF3 Frequency Multiplication Rings linac, vacuum, injection, collider 217
 
  • A. Ghigo, C. Biscari, F. Marcellini, M. Serio, A. Stella
    INFN/LNF, Frascati (Roma)
  • R. Corsini, S. Doebert, G. Geschonke, L. Rinolfi, F. Tecker, P. Urschütz
    CERN, Geneva
  The CLIC Test Facility (CTF3) is in construction at CERN by an international collaboration to demonstrate the feasibility of two beam acceleration scheme at the CLIC parameters. The drive beam of the CTF3 is composed by a fully loaded Linac that generates a long bunch train and two rings that provide the high current and bunch frequency multiplication by interleaving bunch trains. The status of the commissioning of the first ring (Delay Loop) and of the transfer lines are reported together with the installation of the second ring (Combiner Ring).  
 
TUPMA076 Design and Development of Beam Transport Elements for the BARC-ECIL Linac linac, gun, target, focusing 220
 
  • P. Roychowdhury, D. P. Chakravarthy, P. Jain, K. C. Mittal, A. K. Ray
    BARC, Mumbai
  A 10 MeV, 2 kW RF electron linac is under development for cargo scanning. It consists of electron gun, RF linac structure, solenoid focusing magnets, steering magnet, beam diagnostics and x-ray target. The beam diameter requirement at the target is 2mm. Since the beam is to be focused to a diameter of 2mm at the target; the transverse beam optics of the whole linac structure from gun end to the target has been simulated by solving the beam envelope equation. The beam envelope equation has been solved in radial direction by Runga-Kutta method consisting of external focusing field, RF fields, beam perveance and emittance. Various combinations of solenoid magnet focusing have been studied. It has been found that three solenoid magnets are required to focus the beam to a diameter of 2mm at the target, two between the electron gun and the linac entrance and the other between the linac exit and the target. Based on these studies two solenoid magnets has been designed and fabricated. Details of beam optics simulation results and the design of the solenoid magnets will be presented.  
 
TUPMA083 High Quantum Efficiency Photocathode for RF Guns cathode, gun, laser, space-charge 223
 
  • D. Sertore, P. Michelato, L. Monaco, C. Pagani
    INFN/LASA, Segrate (MI)
  • S. Schreiber
    DESY, Hamburg
  • F. Stephan
    DESY Zeuthen, Zeuthen
  High Quantum Efficiency Photocathodes are nowadays routinely used as electron sources for laser driven RF guns. In this paper, we review the production, characterization and operation performances of the Cs2Te photocathodes prepared at INFN Milano – LASA and operated at DESY for the FLASH and the PITZ photoinjectors.  
 
TUPMA085 LEIR: Towards the Nominal Lead Ion Beam ion, injection, linac, vacuum 229
 
  • M. Chanel, M.-E. Angoletta, V. Baggiolini, P. Belochitskii, A. Beuret, A. Blas, J. Borburgh, C. Carli, K. Cornelis, T. Fowler, M. Gourber-Pace, S. Hancock, C. E. Hill, M. Hourican, D. Kuchler, E. Mahner, D. Manglunki, S. Maury, M. M. Paoluzzi, S. Pasinelli, J. Pasternak, U. Raich, F. Roncarolo, C. Rossi, J.-P. Royer, M. Royer, R. Scrivens, L. Sermeus, G. Tranquille, M. Vretenar
    CERN, Geneva
  The Low Energy Ion Ring (LEIR) is a central piece for LHC ion operation at CERN, transforming long Linac3 pulses into high density bunches needed for LHC. The first phase of LEIR commissioning successfully attained its goal of providing the so-called 'early ion beam' (one bunch of 2.25 108 Lead ions) needed for the first LHC ion runs with reduced luminosity. Studies in view of generating the beam needed for nominal ion operation (2 bunches of 4.5 108 ions in LEIR) are being carried out in parallel with the setting-up of the early beam in the accelerators further downstream in the LHC injector chain. The main characteristics of the machine using a new state of the art electron cooler are discussed together with the latest results.  
 
TUPMA094 Electron Cooling Rates in FNAL's Recycler Ring antiproton, emittance, pick-up, instrumentation 238
 
  • A. V. Shemyakin, L. R. Prost
    Fermilab, Batavia, Illinois
  A 0.1-0.5 A, 4.3 MeV DC electron beam provides cooling of 8 GeV antiprotons in Fermilab's Recycler storage ring. The paper presents cooling rate formulas derived in the framework of a simple non-magnetized model and compares them with measurements.  
 
TUPMA113 Design of High Current RF Ion Source for Micromachining Applications ion, plasma, ion-source, extraction 262
 
  • P. Y. Nabhiraj, R. K. Bhandari, C. Mallik, R. Menon
    DAE/VECC, Calcutta
  • G. G, S. Mohan
    IISC, Bangalore
  Liquid Metal Ion Source (LMIS) and Gas Field Emission Ion Source (GFEIS) are the major ones in micromachining applications so far. They have limitations of contaminations and low throughput respectively. Plasma based ion sources can produce heavier ions for higher throughput, lighter ions for fabrication of higher resolution structures, ions for doping, ion assisted direct writing of metallic, oxide, nitride and carbide layers and lines. Considering wide range of applications, a 13.56 MHz inductive coupled plasma (ICP) ion source for producing high brightness ion beams with very low energy spread has been developed. It is a very compact ion source with external helical antenna wound around a 30 mm quartz tube. 1 mA of Argon and 0.5 mA of proton ion beams have been extracted from 2 mm dia aperture in plasma electrode at 3.5 kV extraction potential and ~200W of RF power. Using LabView software and field point modules, an automated plasma diagnostic system has been designed and used to measure the plasma parameters. This paper describes the features of the ion source, ion beams produced, some results of the plasma diagnostics.  
 
TUPMA115 Simulations of Non-uniform High Density Electronegative Plasma for Optimization of H- ions and their Extraction plasma, ion, ion-source, simulation 265
 
  • A . Kumar, S. Kotaiah
    RRCAT, Indore (M. P.)
  • V. K. Senecha
    KEK, Ibaraki
  Numerical simulations of radio frequency multi-cusp volume type H- ion source have been performed under non-uniform electronegative plasma equilibrium conditions in order to understand the physics of formation of various ion species (H+, H-, e- etc.) and for optimization of H- ion formation and extraction. Coupled momentum balance equations along with continuity equations were solved in a cylindrical geometry to obtain the density profile of various ion species. The relevant cross-section data available in the literature as a function of temperature has been used in the computation. The hydrodynamic model of plasma in equilibrium with background neutral gas has been used. Low degree of ionization ( ~1%) has been assumed. The collision less sheath formation, penetration of electric and magnetic field and power requirement to sustain the plasma has been worked out numerically. An effort has been made to give a self-consistent numerical scheme for the solution of inductively coupled plasma (ICP) in equilibrium, and the results obtained have been presented  
 
TUPMA116 Periodic Ion Current Burst in 6.4 GHz ECR Source ion, plasma, ion-source, cyclotron 268
 
  • G. S. Taki, R. K. Bhandari, P. R. Sarma
    DAE/VECC, Calcutta
  • A. G. Drentje
    KVI, Groningen
  • T. Nakagawa
    RIKEN/RARF/CC, Saitama
  • P. K. Ray
    Bengal Engineering and Science University, Howrah
  We studied the enhancement in extracted ion current in the 6.4 GHz ECR ion source at VECC, Kolkata by inserting a negatively biased disc in the main stripping stage. In addition to the expected increase in current, we observed a sudden jump in the current at some low bias voltage. The jump amplitude is larger for higher charge states. In order to understand the origin of the jump, we recently measured the time spectra of high charge state ion current for neon. The time spectra revealed the presence of a burst frequency in the kilohertz range. This frequency shows a correlated jump with the ion current described above. Another feature is that the observed burst frequency shows a good linear correlation with the extracted ion current. This may signify that current per burst is a constant factor, higher current means that there are more number of bursts.  
 
TUPMA122 High Power Neutron Converter for Low Energy Proton/Deuteron Beams: Present Status target, proton, vacuum, radiation 274
 
  • K. Gubin, A. V. Antoshin, M. S. Avilov, D. Bolkhovityanov, S. Fadeev, N. N. Lebedev, P. V. Logachev, P. Martyshkin, S. Shiyankov
    BINP SB RAS, Novosibirsk
  • L. B. Tecchio
    INFN/LNL, Legnaro, Padova
  In BINP, Russia, the high temperature neutron target for SPES project (INFN-LNL, Italy) is proposed. The target is designed to produce up to 10**14 neutron per second within the energy range of several MeV under irradiation by proton/deuteron beam of power up to 200 kW. By now the target prototype is successfully tested. The development of liquid metal driving system and target general design is started. Presented paper describes the design of the target and the target prototype as well as the results of prototype tests under high-power electron beam. Special attention is paid to the carbon material with high content of 13C isotope. The material is produced following the original technology and used for manufacturing the converter irradiated with the proton beam.  
 
TUPMA123 Electron Acceleration in the Wake Field Excited by 200TW Femto Second Laser in Underdense Plasma plasma, laser, scattering, acceleration 277
 
  • R. Taki
    GUAS/AS, Ibaraki
  • W. M. An, Hua, J. F. Hua, W.-H. Huang, C.-X. Tang
    TUB, Beijing
  • S.-I. Kurokawa, K. Nakajima
    KEK, Ibaraki
  Laser-plasama acceleration experiment has been carried out using 200TW, 30fs Ti:Sapphire laser pulses focused on helium gas-jets with F/8.75 optics. Intense mono-energetic electron beams have been produced by controlling plasma length and density precisely. Energy spectral oscillations in respect to ejection angle have been also observed. Measurements of images from Thomson scattering and fluorescence side scattering from plasma indicate highly relativistic effects such as a long self-channeling, hosing instability and filamentation. It seems that these nonlinear phenomena strongly disturb high energy gain acceleration and high quality beam generation.  
 
WEXMA01 Status of KEKB and Upgrade Plan to SuperKEKB luminosity, positron, linac, klystron 280
 
  • M. Yoshida, T. A. Agoh, K. Akai, M. Akemoto, A. Akiyama, A. Arinaga, K. Ebihara, K. Egawa, A. Enomoto, J. W. Flanagan, S. Fukuda, H. Fukuma, Y. Funakoshi, K. Furukawa, T. Furuya, J. Haba, K. Hara, T. Higo, S. Hiramatsu, H. Hisamatsu, H. Honma, T. Honma, T. Ieiri, N. Iida, H. Ikeda, M. Ikeda, S. Inagaki, S. Isagawa, H. Ishii, A. Kabe, E. Kadokura, T. Kageyama, K. Kakihara, E. Kako, S. Kamada, T. Kamitani, K.-I. Kanazawa, H. Katagiri, S. Kato, T. Kawamoto, S. Kazakov, M. Kikuchi, E. Kikutani, H. Koiso, Y. Kojima, I. Komada, T. Kubo, K. Kudo, N. K. Kudo, K. Marutsuka, M. Masuzawa, S. Matsumoto, T. Matsumoto, S. Michizono, K. Mikawa, T. Mimashi, S. Mitsunobu, K. Mori, A. Morita, Y. Morita, H. Nakai, H. Nakajima, T. T. Nakamura, H. Nakanishi, K. Nakanishi, K. Nakao, H. Nakayama, S. Ninomiya, Y. Ogawa, K. Ohmi, Y. Ohnishi, S. Ohsawa, Y. Ohsawa, N. Ohuchi, K. Oide, M. Ono, T. Ozaki, K. Saito, H. Sakai, Y. Sakamoto, M. Sato, M. Satoh, K. Shibata, T. Shidara, M. Shirai, A. Shirakawa, T. Sueno, M. Suetake, Y. Suetsugu, R. Sugahara, T. Sugimura, T. Suwada, S. Takano, S. Takasaki, T. Takenaka, Y. Takeuchi, M. Tawada, M. Tejima, M. Tobiyama, N. Tokuda, S. Uehara, S. Uno, N. Yamamoto, Y. Yamamoto, Y. Yano, K. Yokoyama, Ma. Yoshida, S. I. Yoshimoto, K. Yoshino
    KEK, Ibaraki
  The KEKB is an electron-positron two-ring collider for the leading B meson factory. It consists of an 8 GeV electron ring (HER) and a 3.5 GeV positron ring (LER) and their injector linac. It has been operated since December 1998, and has recently marked the peak luminosity of 16.52 /nb/s. This peak luminosity is obtained under the crab-ready beam optics having the robust operating condition by some efforts to solve the optics problems. The integrated luminosity has also recently exceeded 1.2 /fb /day under the continuous injection mode. We are aiming more luminosity improvement after the crab cavity installation. Further the major upgrade plan for SuperKEKB is expected to achieve 400 /nb/s keeping the baseline of the original proposal and another upgrade plans are also considered towards over 1000 /nb/s based on the recent beam-beam simulation. This paper describes the recent status of KEKB and upgrade plans for SuperKEKB.  
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WEYMA02 India-based Neutrino Observatory - Present Status simulation, site, target, controls 290
 
  • V. M. Datar
    BARC, Mumbai
  The current status of the India based Neutrino Observatory (INO) project is summarized. The two major physics goals are (a) unambiguous demonstration of neutrino oscillation and a more precise measurement of the associated neutrino parameters and (b) to search for matter effects in neutrino oscillation, using the charge identification capability of the magnetized iron calorimeter, which would help determine the signs of one pair of mass differences. The status of the 1 m3 prototype iron calorimetric detector, the design of the 50 kton magnet, the experience with resistive plate chambers used for tracking the charged particles produced in neutrino-iron interactions and the planned electronics and data acquisition system will be presented.  
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WEZH102 Beam Instrumentation Experience at ATF laser, extraction, emittance, radiation 305
 
  • Y. Honda
    KEK, Ibaraki
  Accelerator Test Facility (ATF) at KEK is a test accelerator for linear collider development. It produces a stable low emittance beam that satisfies the requirements in the ILC. Various beam instrumentations (cavity BPM, laser wire, fast feedback, XSR, ODR etc.) have been tested. This presentation will review our recent experiences.  
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WEPMA011 Design and Operating Experience of Triode Electron Guns for Industrial Electron Accelerators gun, cathode, linac, emittance 348
 
  • A. Jain, A. R. Chindarkar, K. C. Mittal
    BARC, Mumbai
  The Accelerator and Pulse Power Division of BARC is presently constructing three industrial electron accelerators for radiation applications. a) a 500 keV, 10 KW Cockcroft-Walton accelerator b) a 10 MeV ,10 KW RF electron linac and c) a 3 MeV, 30 KW DC machine. While the DC accelerators require an almost parallel beam with less than 0.5 degree divergence, the RF linac gun requires a 50 keV , 2 ampere pulsed beam of low emittance Using relativistic electron optics, including space charge effects, very simple triode gun designs with flat cathode, grid and anode apertures which fulfill these requirements and are easy to fabricate experimentally are described. Our operating experience with these guns will also be described.  
 
WEPMA022 Electron Guns and Beamlines in the View of Emittance Compensation gun, emittance, space-charge, cathode 360
 
  • S. V. Miginsky
    BINP SB RAS, Novosibirsk
  Space charge effect is ever of fundamental importance for low-energy parts of accelerators. Criteria of the significance of space charge effect are derived in the presentation. Simple and robust estimations of the emittance degradation in various space charge affected beamlines and electron guns were obtained analytically and numerically. Nonuniform longitudinal and transverse distribution of current, accelerating and bunching were taken into account. The parameters of optimal beamlines for space charge affected beams were estimated.  
 
WEPMA030 The Bunch Lengthening due to Electron Cloud in Positron Storage Ring positron, simulation, storage-ring, damping 366
 
  • Y. D. Liu
    IHEP Beijing, Beijing
  The electron cloud generates not only the transverse wake field but also the longitudinal wake field. The mechanism of the bunch lengthening due to longitudinal wake produced by the electron cloud in the positron storage ring is analyzed. The longitudinal field, which depends on the density of the electron cloud in the storage ring, arises from the accumulation of the electrons near to the center of the bunch during the bunch passage. Based on the longitudinal wake field, tracking method is used to simulate variation of the bunch longitudinal profile in different electron cloud density. According to simulation, the longitudinal action on the bunch from electron cloud is the similar as the potential-well distortion to shift the bunch distribution and give a rise to the bunch deformation. The result has been used to the simulation for BEPCII.  
 
WEPMA050 BPM (Beam Position Monitor) in the PAL Linac and BTL linac, feedback, pick-up, controls 393
 
  • S.-C. Kim, J. Choi, Y. J. Han, J. Y. Huang, D. T. Kim, W. W. Lee, H. J. Park
    PAL, Pohang, Kyungbuk
  In Aug. 2004, thirteen BPMs are installed at BTL (Beam Transport Line), and later in Aug. 2005, three BPM installed at main linac for beam trajectory measurement and feedback. BPMs for the BTL consist of 100mm strip-line electrodes in 150mm long chamber and uses SMA-R type feed-throughs. BPMs of the Linac consist of 57mm strip-line electrodes in 100mm short chamber and SMA-R type feed-throughs. 500MHz log-ratio signal processing circuits are used for the Linac and BTL BPM electronics. BPM data acquisition system is developed as an EPICS IOC by using NI S-series DAQ board and NI LabView 7.1. Best read-out accuracy of BPM system is measured as 20mm including BPM electronics. In this paper, we describe on the status of the BPM and its characteristics for PAL Linac and BTL.  
 
WEPMA068 Comparison of the Methods for Beam Energy Spread Measurement at the VEPP-4M collider, betatron, wiggler, resonance 416
 
  • A. N. Zhuravlev, V. Kiselev, O. I. Meshkov, N. Yu. Muchnoi, V. V. Smaluk, V. N. Zhilich
    BINP SB RAS, Novosibirsk
  The knowledge of beam energy spread is necessary for the experimental program of VEPP-4M collider. In this report we discuss the application of several diagnostics for studying of this value. We applied the Compton BackScattering (CBS) technique for direct measurement of the energy spread of the beam. The obtained data are compared with the value of the spread derived from the radial and longitudinal beam size as well as from betatron frequencies of the beam. The value of energy spread were determined for set of operating mode of the collider.  
 
WEPMA073 Control System based on PCs and PLCs for the L-band Linac at Osaka University controls, linac, power-supply, klystron 425
 
  • R. Kato, G. Isoyama, S. Kashiwagi, S. Suemine, T. Yamamoto
    ISIR, Osaka
  The L-band electron linac at the Institute of Scientific and Industrial Research (ISIR), Osaka University, has been remodeled for higher stability and reproducibility of operation. A computer control system has been newly introduced for the linac not only to realize precise reproducibility of operation but also to make routine operation possible by even an unskilled operator. The new control system is based on personal computers (PCs) and programmable logic controllers (PLCs). The PCs and the PLCs are connected with networks using two different communication protocols. As the network connecting the PLCs, we have chosen FL-net, which is an open PLC network for factory automation. On the other hand, the PCs communicate each other with Ethernet. In order to transfer control information between these two networks with different protocols, one of the PCs is equipped with both FL-net and Ethernet and works as a gateway server. The PC converts data in the common memory in FL-net to the form accessible to the other PCs and vice versa. In this paper, we present details of the control system and operational experiences.  
 
WEPMA078 HTS-ECRIS and Low Energy Beam Transport System of the High Current Injector ion, extraction, ion-source, linac 434
 
  • G. Rodrigues, R. Ahuja, D. Kanjilal, P. Kumar, P. S. Lakshmy, A. Mandal, Y. Mathur, D. Naik, A. Roy, U. Unnam
    IUAC, New Delhi
  A high performance electron cyclotron resonance ion source (ECRIS) called PKDELIS capable of operation at 14.5 and 18 GHz and which uses High Temperature Superconducting (HTS) coils designed jointly by IUAC, Delhi (earlier called NSC), Pantechnik, Caen and ISN, Grenoble is presently in operation. The source is very suitable for operation on a 400 kV high voltage platform for injecting beams from the High Current Injector (HCI) into the Superconducting Linear Accelerator Booster. In the low energy beam transport (LEBT) system of the HCI, the beam extraction and transport becomes more and more challenging. In order to avoid the losses of the beam, the complete transport system is being made as short as possible. In addition, due to the high currents (~10 mA) extracted, the extraction system needs proper cooling requirements and possibility of movement of the electrodes for tuning various A/q beams. Typical axial and radial bremstraahlung spectra have been measured from the ECR plasma. Details will be discussed and further measurements are being explored to obtain a better understanding.  
 
WEPMA083 Design of C-band Standing-wave Accelerating Structure coupling, bunching, linac, resonance 440
 
  • S. H. Kim, M.-H. Cho, W. Namkung, B. Park, H. R. Yang
    POSTECH, Pohang, Kyungbuk
  • S. D. Jang, J.-S. Oh, S. J. Park, Y. G. Son
    PAL, Pohang, Kyungbuk
  We design a C-band standing-wave accelerating structure for a compact electron linac. It is capable to produce electron beams with the beam energy of 4 MeV and the pulsed beam current of 50 mA. It is to be operated in the π/2 mode with the on-axis coupled structure. The beamline is composed of the E-gun and the accelerating column with 3 and half bunching cells and 9 and half normal cells. We design standing-wave RF cavities using the OMEGA3P code to implement the asymmetric magnetic coupling slots. For the beam dynamics study, we use the PARMELA code with the SUPERFISH fields configuration. Without the pre-buncher cavity and the focusing magnets, the lost beam power to the wall is 10 kW for the output beam power of 200 kW, while the transmission is 58%.  
 
WEPMA087 Control System for Beam Diagnostic System of Indus-2 controls, diagnostics, monitoring, injection 449
 
  • A. Chauhan, P. Fatnani, S. Gangopadhyay, B. N. Merh
    RRCAT, Indore (M. P.)
  This paper presents the Beam Diagnostics Control System for Indus-2 that monitors and controls the parameters related to Beam Profile Monitors (BPM), Beam Position Indicators (BPI), Direct Current Transformer (DCCT) and XZ-selection for strip-lines. The system has three-layered architecture. The middle and lower layer have VME stations with CPU cards having RTOS OS-9. The lowest layer has nine stations that house various Analog and Digital I/O boards connected to the actual devices in the field. The boards include 4-channel 16-bit ADC cards developed for BPI interfacing. The middle layer collects the data from lower layer and passes to top layer and passes the commands from top layer to the lower layer. The top layer has the GUI for operator control built using a SCADA software PVSS. It provides various features to the user for graphical display, trending, configuring, controlling, data-logging and selective data monitoring of the parameters. This system finds use right from the beam injection stage to the Orbit correction stage in addition to the normal operation stage of the machine.  
 
WEPMA109 Positron Injector Accelerator and RF System for the ILC positron, target, photon, linac 473
 
  • J. W. Wang, C. Adolphsen, V. Bharadwaj, G. B. Bowden, E. N. Jongewaard, Z. Li, R. H. Miller, J. Sheppard
    SLAC, Menlo Park, California
  Due to the extremely high energy deposition from positrons, electrons, photons and neutrons behind the positron target, and because a solenoid is required to focus the large emittance positron beam, the 1.3 GHz pre-accelerator has to use normal conducting structures up to energy of 400 MeV. There are many challenges in the design of the normal-conducting portion of the ILC positron injector system such as obtaining high positron yield with required emittance, achieving adequate cooling with the high RF and particle loss heating, and sustaining high accelerator gradients during millisecond-long pulses in a strong magnetic field. Considering issues of feasibility, reliability and cost savings for the ILC, the proposed design for the positron injector contains both standing-wave (SW) and traveling-wave (TW) L-band accelerator structures. A short version of the new type of the SW section is under fabrication and testing, an updated status report is given. This paper also covers the acceleration vs. deceleration for pre accelerator sections, SW vs. TW structures, as well as the longitudinal matching from target to linac and linac to damping ring.

* Work supported by U. S. Department of Energy, contract DE-AC02-76SF00515.

 
 
WEPMA112 Thermal Simulations of a Photocathode R. F. Gun gun, simulation, vacuum, laser 482
 
  • B. Biswas, S. Krishnagopal, A. Kumar, S. Lal, K. K. Pant
    RRCAT, Indore (M. P.)
  We are developing a photocathode linac, which uses a 2856 MHz r.f. gun, with a copper cathode driven by a 102 MHz, 266 nm laser at inclined incidence. The laser photocathode r.f. gun is a 1.6 cell BNL/SLAC/UCLA type III r.f. gun. In this paper we present the dynamic thermal cooling simulations to calculate the structural deformations and consequent frequency drift of the gun. We have done a complete r.f.-thermal-structural-r.f finite-element analysis (FEA) of the gun in that order, using ANSYS/MULTIPHYSICS. We find that with the present coolant channel design the gun can operate at up to 2 Hz without any significant change in resonant frequency and field balance.  
 
WEPMA122 Design and Development of 30 MeV, 3 kW RF Electron LINAC linac, target, coupling, acceleration 491
 
  • V. T. Nimje, D. Bhattacharjee, K. Dixit, D. Jayaprakash, K. C. Mittal, A. K. Ray
    BARC, Mumbai
  A 30 MeV, 3 kW RF Electron linac for neutron generation is being designed and developed. The Design parameters, beam studies etc. will be described in this paper.  
 
WEPMA123 Comparative Analysis of Blade Tuner Optimization Options for the ILC simulation, superconducting-RF, vacuum 494
 
  • C. Pagani, N. Panzeri
    INFN/LASA, Segrate (MI)
  Following the successful experience of the blade tuner concept for superconducting cavities, a full parametric analysis has been performed for ILC cost optimization. Different design details have been reconsidered and optimized on the basis of their impact on the ILC requirements and on production costs. Two different designs have been then developed for two options of fabrication material: titanium or stainless steel. The realization of two prototypes, one for each type, has been recently launched for the designs qualification and comparison. In this paper we discuss the optimization rationales and the expected differences in cost and tuner integration and performances. Cold tests on cavities will be at the basis of the final choice for the ILC.  
 
WEPMA132 Superconducting Niobium Resonator Fabrication And Testing At IUAC linac, coupling, controls, proton 500
 
  • P. N. Prakash, D. Kanjilal, K. K. MISTRI, A. Roy, S. S.K. Sonti, J. Zacharias
    IUAC, New Delhi
  Superconducting niobium resonator fabrication and testing facilities have been developed at Inter-University Accelerator Centre. The facilities are used to construct niobium resonators for the superconducting booster linac as well as for future accelerator development projects. In the first phase a single quarter wave resonator (QWR) was successfully fabricated and tested. In the second phase two completely indigenously built QWRs were constructed. In cold tests at 4.5 K one of them performed at 3.5 MV/m with 3.5 W RF input power, exceeding the nominal design goal. After the successful completion of this project production of fifteen QWRs for the 2nd and 3rd linac modules began. This work has progressed sufficiently and we plan to complete the production by mid ‘2007. In addition to resonator fabrication the facilities have been used for other developments such as a new design of niobium-stainless steel transition assembly, slow tuner modifications, and repairing of the existing QWRs. Details of the activities and performance of the resonators will be presented.  
 
WEPMA139 Development of High-power Microwave Devices in Toshiba klystron, vacuum, cathode, linac 511
 
  • K. Hayashi, M. Irikura, Y. Okubo, H. Urakata
    TETD, Otawara
  • M. Y. Miyake
    Toshiba, Yokohama
  Vacuum microwave devices continue to be essential for high-power RF accelerator systems and plasma heating or current drive systems for fusion experimental devices. Klystrons are suitable for use in amplification at the frequency ranges from 300 MHz to X band, while gyrotrons are mainly utilized in the millimeter wave range. Input couplers also play an important role in the building of acceleration cavity systems. TETD (Toshiba Electron Tubes & Devices Co., LTD.) has been developing these vacuum microwave devices in collaboration with some Japanese research institutes. Two kinds of long-pulse klystron for the J-PARC project were developed in collaboration with KEK and JAEA, which each have their operation frequencies, 324 MHz and 972 MHz. Both tubes output 3 MW with the pulse duration of 0.62 ms at the repetition frequency of 50 pps. They have a triode-type electron gun and same beam parameters and operate with an anode-modulating mode to reduce the cost of the power supply system.  
 
WEPMA140 Development of C-band Multi Beam Sub-booster Klystron klystron, simulation, gun, cathode 514
 
  • M. Yoshida, S. Fukuda
    KEK, Ibaraki
  • V. E. Teryaev
    BINP SB RAS, Novosibirsk
  A C-band small multi beam klystron (MBK) has been under development. It is designed for the sub-booster klystron which is required to drive multiple 50 MW C-band klystrons for the SuperKEKB injector upgrade plan. The designed output power is over 100 kW in case of the applied voltage of 25 kV which is suitable for the existing pulse modulator for the S-band sub-booster klystron. At this operating condition, the designed micro-perveances of the total and the each beamlet are 2.0 and 0.25 respectively. The design overview will be presented.  
 
WEPMA144 High Power Microwave Generation From Coaxial Virtual Cathode Oscillator cathode, impedance, plasma, space-charge 523
 
  • A. Roy, RM. Menon, S. Mitra, K. C. Mittal, J. Mondal, D. D. Praveen Kumar, A. S. Sharma
    BARC, Mumbai
  A coaxial virtual cathode oscillator (VIRCATOR) has been designed to generate Relativistic Electron Beams and High Power Microwaves. Coaxial virtual cathode oscillators are known for better efficiency compared to the axial virtual cathode oscillators. This Coaxial VIRCATOR has been designed for the KALI-5000 (1MeV, 60kA, 100 ns) pulse power system. Provision for a large anode cathode gap has been kept to avoid the prepulse effect during the electron beam generation from the KALI-5000 system. Experimental studies are carried out to generate and characterize Relativistic Electron Beams and High Power Microwaves. Relativistic Electron Beams are generated by the Coaxial Explosively emitted graphite cathodes. Electron beam voltage has been measured by a copper sulphate voltage divider and beam current by a B-dot probe. High Power Microwaves are detected by the glow of neon lamps placed closed to the output window.  
 
THC3MA04 Status of the Novosibirsk High Power Terahertz FEL radiation, undulator, laser, vacuum 616
 
  • S. V. Miginsky, B. A. Knyazev, E. I. Kolobanov, V. V. Kotenkov, V. V. Kubarev, G. Kulipanov, A. V. Kuzmin, A. S. Lakhtychkin, A. N. Matveenko, L. E. Medvedev, L. A. Mironenko, A. D. Oreshkov, A. V. Ovchar, V. M. Popik, T. V. Salikova, M. A. Scheglov, S. S. Serednyakov, O. A. Shevchenko, A. N. Skrinsky, N. Vinokurov
    BINP SB RAS, Novosibirsk
  • D. Kayran
    BNL, Upton, Long Island, New York
  The first stage of Novosibirsk high-power free-electron laser (FEL) was commissioned in 2003. It is based on the normal conducting CW energy recovery linac. Now the FEL provides electromagnetic radiation in the wavelength range 120–180 micrometers. The average power is 400 W. The minimum measured line width is 0.3%, which is close to the Fourier-transform limit. The assembly of user beamline is in progress, parts of the full-scale machine are manufactured. The latter will operate in the near IR region and will provide higher average power.  
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THC3MA05 Bunch Compression using the Transport Line and Short Bunch revolving in NewSUBARU linac, injection, storage-ring, radiation 619
 
  • S. Suzuki, T. Asaka
    JASRI/SPring-8, Hyogo-ken
  • Y. Hisaoka, T. Matsubara, T. Mitsui, Y. Shoji
    NewSUBARU/SPring-8, Laboratory of Advanced Science and Technology for Industry (LASTI), Hyogo
  We have demonstrated the idea of circulating a short, intense linac bunch for some tens of turns in an isochronous ring. We compressed a bunch from the SPring-8 linac to a few picoseconds rms by means of an energy compression system and a beam transport line from the linac to NewSUBARU. The NewSUBARU storage ring was set to a quasi-isochronous condition and the bunch circulated for some tens of turns after injection while maintaining the short bunch length. And we measured the coherents synchrotron radiation at 90-140GHz by semiconducter detector. The bunch length is maintained in about 20 microseconds, but the CSR power decreases little by little.  
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THC3H101 Status of the Industrial RF-accelerators in BINP extraction, vacuum, coupling, shielding 622
 
  • V. Auslender, A. A. Bryazgin, V. G. Cheskidov, B. L. Faktorovich, V. Gorbunov, I. V. Gornakov, V. E. Nekhaev, A. D. Panfilov, A. I. Sidorov, V. O. Tkachenko, A. F.A. Tuvik, L. A. Voronin
    BINP SB RAS, Novosibirsk
  ILU type of industrial RF accelerators developed and producing in BINP involve the energy range from 0.5 to 5 MeV with power up to 50 kWt. Compact size of this type of the accelerators and no necessity of SF6 allows to use their in the wide spectrum of technology, including the food and drug treatment. Described the status of the novel ILU-12 accelerator with energy up to 5 MeV and power up to 300 kWt. BINP developed series of X-ray converters based on tantalum and wolfram targets. The family of ILU accelerators includes the ion accelerator ILU-9. This report involves the new radiation technologies which use ILU type of accelerators, based on e-beam, X-ray and ion beams.  
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THC3H103 The Compact Induction Circular Accelerator for Radiation Technologies induction, betatron, acceleration, focusing 628
 
  • G. Dolbilov
    JINR, Dubna, Moscow Region
  The variant of the circular accelerator of electrons with energy up to 10 ?eV is discussed. Acceleration is carried out by an induction electric field on a constant equilibrium orbit of radius about 50 cm. For reduction of reactive power of the accelerator the alternating magnetic fields are concentrated in small volume near to the equilibrium orbit. Use of high-frequency magnetic fields (tens or hundreds ?Hz) allows to increase power of the accelerated electron beam up to some tens kW or hundred kW.  
 
THPMA005 SCSS RF Control Toward 5712 MHz Phase Accuracy of One Degree controls, klystron, laser, acceleration 634
 
  • Y. Otake, M. Kitamura, H. Maesaka, T. Shintake
    RIKEN Spring-8 Harima, Hyogo
  • T. Fukui, N. Hosoda, T. Ohata, T. Ohshima
    JASRI/SPring-8, Hyogo-ken
  To check the feasibility of X-FEL(SCSS), the 250 MeV prototype accelerator was constructed at SPring-8. The low level RF control system with a 5712 MHz pulsed RF signal was built to achieve very-tight requirements that were phase stability and resolution of less than 1 deg.. These requirements correspond to a beam energy variation of 10-4 at the crest acceleration and time stability and resolution of less than 500 fs. To realize the requirements, IQ modulators/detectors, arbitrary wave form generators/detectors of VME modules to handle an IQ function were developed. The PID control and the adaptive control method, which the modules can manipulate, were employed to obtain the requirements. We finally achieved the phase setting and detecting resolution of the IQ detectors/modulators of ± 0.5 deg.. Decreasing the phase drift was achieved by the PID control program, and reducing the phase variation within a pulse width of 2 us was achieved by the adaptive control function on the VME modules. The unnecessary time jitters of the pulse were also automatically detected by the module function. In this paper, we describe a summary of the system and its phase control performance.  
 
THPMA015 Performance of 6 MW Peak, 25kW Average Power Microwave System for 10 MeV, 10 kW Electron LINAC klystron, linac, gun, vacuum 649
 
  • P. Shrivastava, P. Mohania, J. Mulchandani, Y. W. Wahnmode
    RRCAT, Indore (M. P.)
  An S-Band microawave system with peak power capability of 6MW and average power capability of 25 kW was designed, constructed and commissioned at RRCAT. The inhouse development of various microwave technologies and pulse modulator technologies was successfully achieved and the microwave system was interfaced to the 10MeV, 10kW electron LINAC. The electron LINAC could be tested to full rated energy and power using the present microwave system. The present paper highlights the details of the performance results.  
 
THPMA039 300 kV/ 6 kW Power Supply System for Self-shielded Low Energy DC Accelerator at RRCAT Indore controls, power-supply, damping, cathode 679
 
  • R. Banwari, A. Kasliwal, S. Kotaiah, A. Kumar, T. G. Pandit, P. R. Peteti, A. Upadhyay
    RRCAT, Indore (M. P.)
  A compact, low energy, self-shielded dc accelerator for industrial applications requiring beam energy in the range of 100 to 300 keV is under development at RRCAT, Indore. The power supply and control system for this accelerator is discussed here in this paper. The high voltage source is a series fed cascade generator driven by a 30 kHz sine wave inverter. Two asymmetrical cascade generators are run in parallel to enhance the current capacity of the generator. A 15-0-15 kV, 30 kHz ferrite core transformer interfaces the cascade generators with IGBT based H-bridge inverter. A buck chopper controls the dc bus voltage of the inverter so as to control the terminal voltage of the high voltage generator. A low power high frequency inverter generates the filament power supply floating at terminal voltage of the accelerator through a capacitive isolation column. Control of the filament power supply is achieved by sensing the accelerator beam current and controlling the low power inverter in a closed loop. A PC based control system designed with Lab-view 7.0 software and ADUC812 Micro-converter cards monitors and displays the various parameters of the power supply and accelerator.  
 
THPMA043 Development of 3 MeV, 30 kW DC Electron Accelerator at EBC, Kharghar controls, vacuum, radiation, gun 682
 
  • K. C. Mittal, S. Acharya, R. Agarwal, R. Barnwal, D. P. Chakravarthy, A. S. Chawala, A. R. Chindarkar, S. R. Ghodke, B. S. Israel, A. Jain, D. Jayaprakash, M. K. Kumar, M. K. Kumar, R. L. Mishra, K. V. Nagesh, K. Nanu, M. K. Pandey, G. P. Puthran, R. N. Rajan, S. R. Raul, A. K. Ray, P. C. Saroj, D. K. Sharma, V. Sharma, R. Shilendra, S. K. Suneet, S. B. Supriya, D. P. Suryaprakash
    BARC, Mumbai
  A 3 MeV, 30 kW DC industrial electron accelerator has been designed and is in advanced stage of development at EBC, Kharghar, Navi Mumbai. Electron beam at 5 keV is generated in electron gun with LaB6 cathode and is injected into accelerating column at a vacuum of 10-7 torr. After acceleration, the beam is scanned and taken out in air through a 100 cm X 7 cm titanium window for radiation processing applications. The high voltage accelerating power supply is based on a capacitive coupled parallel fed voltage multiplier scheme operating at 120 kHz. A 50 kW oscillator feeds power to high voltage multiplier column. The electron gun, accelerating column and high voltage multiplier column are housed in accelerator tank filled with SF6 gas insulation at 6 kg/sq.cm. The accelerator is located in a RCC building with product conveyor for handling products. A central computerized control system is adopted for operation of the accelerator. Accelerator is in the advance stage of commissioning. This paper describes the design details and current status of the accelerator and its various subsystems.  
 
THPMA046 Study and Comparison of Reactive Power Compensation Schemes for Air-Core Transformer in ELV-type DC Accelerators simulation, synchrotron, vacuum, impedance 688
 
  • M. Borage, S. Kotaiah, S. R. Tiwari
    RRCAT, Indore (M. P.)
  The ELV-type electron accelerators are widely used in industrial and research applications. The scheme for generating high voltage in these machines is based on air-core transformer, which has large leakage inductance and small magnetizing inductance. To minimize the reactive power loading on the inverter feeding the primary winding, suitable compensation scheme must be employed. Conventional compensation scheme using shunt capacitor and a series inductor however can minimize the reactive power only at one particular loading condition. Also the compensating inductor becomes heavy and bulky. In this paper, the results of studies done to investigate suitability of various compensation networks are presented. Following desirable features are looked for: (1) Near-unity power factor operation under all loading conditions. (2) Nearly load independent output voltage. (3) Minimum additional reactive components. (4) Elimination of compensating inductor. Characteristics of compensation networks are studied and compared using simulation software PSpice wherein with the proposed method, normalized results suitable for comparison are directly obtained.  
 
THPMA047 Stair Current Output Power Supply for Switching Magnet controls, power-supply, feedback, quadrupole 691
 
  • S.-H. Jeong, J. Choi, H.-S. Kang, D. E. Kim, K.-H. Park
    PAL, Pohang, Kyungbuk
  The switching magnet for beam distribution to 5 beamlines of 20-MeV PEFP is served with DSP-controlled PWM switching-mode converter. This converter is employed IGBT module and a DSP (Digital Signal Processor) that is operated at ?350A, 2.5 Hz stair output. Current feedback and input voltage feed-forward control schemes are applied to improve the output current stability. Designed filter result in the good stability of each stair. Simulation and experimental results show that the implemented converter achieves stable repeat response at each stair and feasibility for versatile power supply.  
 
THPMA062 An APPLE-II Type Helical Undulator for SSRF undulator, polarization, synchrotron, radiation 714
 
  • Q. G. Zhou, M. Zhang
    SINAP, Shanghai
  Shanghai Synchrotron Radiation Facility (SSRF) is an intermediate energy (3.5GeV) light source under construction. Specially designed insertion devices will be required to realize the high brightness photon beams made possible by the low emittance electron beam. The first insertion device to be designed is a 4.2m long, 10cm period, APPLE-II type helical undulator, U10.0. The U10.0 will use a permanent magnetic configuration corresponding to four standard Halbach-type magnet rows which consist of two pairs of planar permanent magnet rows above and below the electron orbit plane. The C-frame support structure is selected. The design of U10.0, including magnetic structure, backing beams, support structures and drive systems, is described  
 
THPMA065 Theoretical Analysis of the Recovery Times in Low Pressure Sparkgaps - Positive Ion Diffusion Method ion, plasma 723
 
  • K. V. Nagesh, K. V. Nagesh
    BARC, Mumbai
  The recovery characteristics of the low-pressure sparkgaps in the time interval of 300*s to 50ms, for hydrogen, argon and deuterium gases,had shown thatthat the breakdown voltage under second pulse is higher than the breakdown voltage under first pulse along the left hand side of Paschen's characteristics and defined as over recovery (>100% recovery). An attempt has been made to calculate and analyze the recovery times of low pressure sparkgaps based on diffusion of positive ions here. The recovery times are calculated based on the reported data of plasma diffusion rates. The spherical ambipolar and free diffusion recovery times are generally in good agreement with the experimental recovery times at higher pressures. The cylindrical ambipolar and free diffusion recovery times are an order of magnitude lower than spherical diffusion recovery times. The recovery times are not in good agreement for positive polarity experimental recovery times. The theoretical calculation of recovery times, comparison of calculated and experimental recovery times and discussions are presented in this paper.  
 
THPMA067 Stability Analysis of a Klystron-Modulator for PAL XFEL klystron, impedance, linac, free-electron-laser 729
 
  • J.-S. Oh, C. W. Chung, S. D. Jang, S. J. Kwon, Y. G. Son, J.-H. Suh
    PAL, Pohang, Kyungbuk
  • I. S. Ko, W. Namkung
    POSTECH, Pohang, Kyungbuk
  The PAL (Pohang Accelerator Laboratory) is persuading to construct a SASE-XFEL facility (PAL XFEL). The stable electron beam is essential for the single-pass free electron laser facility. The beam stability is governed by an accelerating RF field, of which fluctuation is mainly caused by the modulation of klystron voltage pulses. Therefore, it is directly determined by the charging stability of a modulator that uses an inverter charging system. The stable charging power supply can be realized by a stable probing and correct manipulating of a charging signal, a fine control of charging current, low noise environment, etc. This paper shows the detail analysis of the stability dependency of a klystron-modulator on the related parameters.  
 
THPMA073 Artificial Neural Network Calculates Backward Wave Oscillator Parameters Reliably For Pulsed Accelerators simulation, plasma, controls, radiation 738
 
  • A. Gokhale
    Terna Collage of Engineering, Navi Mumbai
  • B. P. Dubey
    Bhabha Atomic Research Center, Computer Division, Mumbai
  • A. S. Sharma
    BARC, Mumbai
  A method of quickly and accurately getting the dispersion curves for a slow wave structure filled with plasma is investigated. A universal dispersion equation is derived by utilizing the field theory and expressing the slow wave structure's profile in a finite Fourier series. In principle simulation program takes nearly 6 to 8 hours to generate a single result. A trained Artificial Neural Network, used in this study, calculates the BWO dispersion curve in a fraction of a second accurately and reliably.  
 
THPMA074 Operational Analysis of Klystron-Modulator System for PLS 2.5-GeV Electron Linac klystron, linac, feedback, controls 740
 
  • S. S. Park, J. Y. Huang, S. H. Kim, S.-C. Kim
    PAL, Pohang, Kyungbuk
  The klystron-modulator(K&M) system of the Pohang Accelerator Laboratory (PAL) generates high power microwaves for the acceleration of 2.5 GeV electron beams. There are 12 modules of K&M system to accelerate electron beams up to 2.5 GeV nominal beam energy. One module of the K&M system consists of the 200 MW modulator and an 80 MW S-band (2856 MHZ) klystron tube. The total accumulated high-voltage run-time of the oldest unit among the 12 K&M systems has reached nearly 92,300 hours as of June 2006. The overall system availability is well over 95%. In this paper, we review overall system performance of the high-power K&M system and the operational status of the klystrons and thyratron lifetimes, and overall system's availability will be analyzed for the period of 1994 to June 2006.  
 
THPMA087 Prototype Beam Dump For 10 kW LINAC linac, radiation, radioactivity, beam-transport 764
 
  • R. S. Sandha, S. C. Bapna, J. Dwivedi, V. C. Petwal, H. C. Soni
    RRCAT, Indore (M. P.)
  A 10 MeV, 10 kW electron LINAC has been developed at RRCAT, Indore for developing applications in the area of radiation processing of agricultural products and medical sterilization. This paper presents the functional requirements, design and manufacturing aspects of beam dump for this LINAC. Activation, conversion of electron energy into primary bremmstralung and radiation damage are important parameters for material selection of the beam dump. Other important parameters considered are mechanical strength, thermal conductivity, corrosion in ozone environment and manufacturability. Calculations of heat deposition due to electrons & photons, thermal design, hydraulic, structural and engineering design were done. FEM based analysis was performed for calculating temperature rise, deformation and stresses. The maximum temperature is estimated to be about 320 K. A prototype beam dump has been manufactured and installed and it is being tested under actual operating conditions.  
 
THPMA088 Bremsstrahlung Converter For High Power EB Radiation Processing Facility target, photon, radiation, radioactivity 767
 
  • V. C. Petwal, S. C. Bapna, S. Kotaiah, R. S. Sandha
    RRCAT, Indore (M. P.)
  • K. V. Subbaiah
    Safety Research Institute, Indira Gandhi Center for Atomic Research, Tamilnadu
  A radiation processing facility based on 10 kW Linac is being set up at RRCAT for irradiation of food products and sterilization of medical items. The facility is planned to operate in electron (10 MeV) and X-ray (5 & 7.5 MeV)mode. The required X-rays will be generated by bombarding an optimised target with 5 or 7.5 MeV electron beam. Monte Carlo simulation with MCNP has been performed to optimise the design of the targets for maximizing the X-ray output. The composite target is made of Ta, water & SS. Characteristics of the emerging X-ray field e.g. photon energy spectrum, angular distribution, radial dose and depth dose distribution in unit density material have been simulated & compared for 5 & 7.5 MeV. Our simulation results show that for optimised design, the fraction of the energy transmitted at 5 & 7.5 MeV is 9.3% & 14.2 % respectively, which is useful for radiation processing. The most probable energy of the photons is 0.3 MeV for both 5 and 7.5 MeV electrons and the average energy is 0.84 MeV & 1.24 MeV respectively. Large fraction of electron beam power is dissipated as heat in the targets. Necessary data has been generated to carry out thermal design.  
 
THPMA094 SF6 Gas Handling System for 3 MeV, 30 kW Industrial Electron Beam Accelerator at EBC, Kharghar, Navi Mumbai vacuum, controls, gun, instrumentation 779
 
  • S. R. Ghodke, K. K. Abdullah, R. Barnwal, D. P. Chakravarthy, D. Jayaprakash, M. K. Kumar, N. Lawangare, R. L. Mishra, K. C. Mittal, K. Nanu, G. P. Puthran, A. K. Ray, S. B. Supriya, V. S. Veer
    BARC, Mumbai
  The 3 MeV Accelerator Project involves designing, fabrication, installation and commissioning of a 3 MeV, 30 kW Industrial Electron Beam Accelerator with a terminal voltage of 3 MV and is housed inside the Electron Beam Centre building at Kharghar, Navi Mumbai. The Accelerator has capability of delivering electron beam of 3 MeV energy for radiation processing applications. For ecological and economical reason, the SF6 gas is reincorporated into closed cycle because gas should not be released into the atmosphere. The aim of the SF6 gas handling system is to introduce the gas at high pressure to the accelerator tank after evacuation and to bring back into the storage tanks with minimum loss. The gas handling system also provides purification of gas, prevention from mixing with air or any other substances, which may contaminate and thus bring down the high voltage insulation characteristics of the gas. This paper discusses about mechanical design, fabrication, testing and safety of different components of SF6 gas handling system such as gas piping, non lubricating compressor, dryer, vacuum pump, dust & oil filters, storage tanks etc.  
 
THPMA100 Multipacting Study of Linac Prebuncher at CAMD linac, focusing, power-supply, storage-ring 785
 
  • Y. Wang
    LSU/CAMD, Baton Rouge, Louisiana
  Multipacting currents can absorb RF energy and produce breakdown in the prebuncher cavity of CAMD linac*. This phenomenon starts when the magnetic field to focus the electron beam is applied. The multipacting has been studied in different magnetic field and RF electric field, and can be eliminated by RF processing. In the paper, the theoretical and experimental results of multipacting study will be presented; moreover, the operability of the system will be analyzed.

* Y. Wang et al., “Upgrades of the Linac System at CAMD”. PAC2003, Portland, May 2003, p. 2892.

 
 
THPMA114 Activities on the Nuclear Data Measurement at the Pohang Neutron Facility Based on Electron Linac target, linac, quadrupole, background 800
 
  • G. N. Kim
    Kyungpook National University, Daegu
  • M.-H. Cho, I. S. Ko, W. Namkung
    POSTECH, Pohang, Kyungbuk
  • H.-S. Kang, Y. D. Oh
    PAL, Pohang, Kyungbuk
  We report the present status of the Pohang Neutron Facility which consists of an electron linear accelerator, a water-cooled Ta target, and a 12-m time-of-flight path. We measured the neutron total cross-sections in the neutron energy range from 0.1 eV to few hundreds eV by using the neutron time-of-flight method. A 6LiZnS(Ag) glass scintillator was used as a neutron detector. The neutron flight path from the water-cooled Ta target to the neutron detector was 12.1 m. The background level was determined by using notch-filters of Co, In, Ta, and Cd sheets. In order to reduce the gamma rays from Bremsstrahlung and those from neutron capture, we employed a neutron-gamma separation system based on their different pulse shapes. The present measurements of Ta, Hf, Ag, and Mo samples are in general agreement with the evaluated data in ENDF/B-VI. The resonance parameters were extracted from the transmission data from the SAMMY fitting and compared with the previous ones.  
 
THPMA118 Electron Accelerator of ELV-type and their Worldwide Application controls, extraction, vacuum, radiation 809
 
  • N. K. Kuksanov, S. Fadeev, P. I. Nemytov, R. A. Salimov, M. E. veis
    BINP SB RAS, Novosibirsk
  D. C.ELV accelerators are the most popular Russian accelerators for industrial and research purposes. More than 100 accelerators were deliverd from Germany at west to Japan and Malaya at east. By now the total operation time exceeds 1000 accelerato-years. The design and schematic solutions provide the long term and round-the -clock operation. The specific features of the ELV-accelerators are the simplicity of design, convenience and ease in control and reliability in operation. ELV-type acceleratodrs is covering the energy range from 0.2 to 2.5 MeV with a beam current of up to 500 mA and maximum power of up to 400 kW. The accumulated experience in the design, development, and manufacturing of the ELV-series accelerators enables us to propose the machines which by their parameters do not rank below but in the majority of cases even surpassing the best world samples of such machines. In the work presented here the parameters of ELV electron accelerators are given and the main systems of the accelerator and a wide set of supplementary devices extending the application range of the accelerator is given. The main industrial applications of ELV accelerators are considered also.  
 
THPMA126 Beam Optics Design for DC High-voltage Accelerator of MW Level cathode, gun, extraction, optics 818
 
  • H. B. WANG, X. Jin, M. Li, X. S. Liu, Z. Xu
    CAEP/IAE, Mianyang, Sichuan
  Here, we report on the working group ''beam optics design'' of MW levels dc high-voltage accelerator, that will be used in radiation technologies in large-scale industrial production (flue gas treatment, metallurgy; waste water treatment, etc.). This workshop also had working groups on ''Electron Guns Designs and Beam control device'', ''MW level high-voltage power supply designs and fabrication'', and ''Beam scanning and extraction devices designs and fabrication''. Comparing with existent high-voltage accelerators, our facility have higher average power of >500mA dc, which resulting in some technological challenges on beam production, power supply, and beam extraction. Here, we are concerned with several proposals that other laboratories have been working on. Subjects of concern are optics, accelerator design and modeling, stability requirements that connects the conventional DC high-voltage accelerators for round-the-clock operation. We describe the design, the projected performance and the status of our facility.

WANG Han-bin*, XU Zhou, JIN Xiao, LI Ming, LIU Xi-san

 
 
THPMA127 Development of L-band Electron Accelerator for Irradiation Source klystron, linac, bunching, beam-loading 821
 
  • S. H. Kim, M.-H. Cho, S.-I. Moon, W. Namkung, B. Park, H. R. Yang
    POSTECH, Pohang, Kyungbuk
  • S. D. Jang, J.-S. Oh, S. J. Park, Y. G. Son
    PAL, Pohang, Kyungbuk
  An intense L-band electron accelerator is under development for irradiation applications. It is capable of producing 10-MeV electron beams of 30 kW with the fully beam-loaded condition. The accelerator is powered by a pulsed klystron of 1.3 GHz and 25 MW with the 60-kW average power. The accelerating column, a traveling-wave structure, is operated with the 2π/3 mode and is installed vertically with other beam-line components. With the beam dynamics simulation, the beam transmission efficiency is over 90% and the beam size is enough to clear the apertures. Design details and the status of installation are presented for the L-band electron accelerator.  
 
THPMA129 High Power Industrial Electron Accelerator controls, power-supply, vacuum, industrial-accelerators 824
 
  • S. C. Bapna, R. Banwari, M. Borage, A. Kasliwal, S. Kotaiah, A. Kumar, P. Kumar, R. Promod, S. R. Tiwari, S. V. Venkateswaran
    RRCAT, Indore (M. P.)
  Development of 2.5MeV/ 100kW air-core transformer type electron Accelerator is in progress at RRCAT in collaboration with BINP, Russia. Energy of the accelerator is variable from 1 to 2.5 MeV with maximum beam current, power and beam scanning width of 50mA, 100kW and 1.5m respectively. High voltage generator, accelerating tube and injector control unit are housed inside the tank filled with pressurized SF6. A 430Hz, 150kW input power source to high voltage generator is based on a high-frequency switching (25kHz) dual half-bridge inverter and modular in construction with 6 modules (each 30kW) operating in parallel. In case one module fails, remaining modules will continue to feed power without de-rating. In this scheme, transformer leakage and magnetizing inductances will be compensated with high voltage capacitors eliminating the need of bulky inductors. The beam is scanned in two mutually perpendicular directions using scanning magnets. The control system uses microcontroller ADuC 812 based cards. Each subsystem will have one such card and a single RS485 multidrop communication link with the PC. The accelerator will be useful for various industrial applications.  
 
FRXMA01 Progress of the Laser-Plasma Acceleration Research at KERI laser, plasma, acceleration, background 832
 
  • H. Suk, M. S. Hur, J.-U. Kim, S. H.Yoo. Yoo
    KERI, Changwon
  • J.-H. Jang
    KAERI, Daejon
  There rise great interest worldwide in plasma accelerators driven by ultra-intense lasers or electron beams which make it possible to generate ultra-high gradient acceleration and high quality particle beams in a much more compact size compared with conventional accelerators. A frontier research on laser and plasma accelerators is focused on high energy electron acceleration and ultra-short coherent X-ray and Tera Hertz radiations as their applications. These achievements will provide not only a wide range of sciences with benefits of a table-top accelerator but also a basic science with a tool of ultrahigh energy accelerators probing an unknown extremely microscopic world. Harnessing the recent advance of ultra-intense ultra-short pulse lasers and accelerators, the worldwide research has made a tremendous breakthrough in demonstrating high-energy high-quality particle beams in a compact scale. This talk highlights recent progress of results on laser and plasma based acceleration experiments to quest for physics of acceleration and beam physics in plasma and to present new outlook for applications of laser and plasma accelerators.  
 
FRYMA01 Experiences With The Hera Lepton-Proton Collider proton, luminosity, lepton, resonance 842
 
  • F. J. Willeke
    DESY, Hamburg
  A review of the experience of operating the HERA lepton proton collider with a high luminosity of up to 5∙1031cm-2s-1, a discussion of the important accelerator physics issues and a summary of the most important physics results of the lepton-hadron (ep) collider HERA is presented.