kicker

Paper	Title	Other Keywords	Page
MOPLT009	The Design of the New Fast Extraction Channel for LHC	extraction, septum, emittance, proton	548
	J. Borburgh, B. Balhan, E.H.R. Gaxiola, B. Goddard, Y. Kadi, J.A. Uythoven CERN, Geneva
	The Large Hadron Collider (LHC) project requires the modification of the existing extraction channel in the long straight section 6 of the CERN Super Proton Synchrotron (SPS). The new extraction will be used to transfer protons at 450 Gev/c as well as ions via the 2.8 km long transfer line TI 2 to the clockwise ring of the LHC. As the resonant extraction to the present SPS west area will be stopped after 2004, the electrostatic septa will be replaced by new fast extraction kicker magnets. The girder for the existing DC septa will be modified to accommodate a new septum protection element. Other modifications concern the replacement of a machine quadrupole, a new scheme for the extraction bumpers, new instrumentation and interlocks. The requirements and the design of the new extraction channel will be described as well as the modifications which will mainly be carried out in the long SPS shutdown 2005.
MOPLT015	Reliability Issues of the LHC Beam Dumping System	dumping, extraction, collider, hadron	563
	R. Filippini, E. Carlier, B. Goddard, J.A. Uythoven CERN, Geneva
	The Beam Dumping System of the Large Hadron Collider, presently under construction at CERN, must function with utmost reliability to protect the personnel, minimize the risk of severe damage to the machine and avoid undue impact to the environment. The dumping action must be synchronized with the particle free gap and the field of the extraction and dilution elements must be well adjusted to the beam energy. The measures taken to arrive at a reliable and safe system will be described, like the adoption of fault tolerant design principles and other safety related features as comprehensive monitoring, diagnostics and protection facilities. These issues will be discussed in the general framework of the IEC standard recommendations for safety critical systems. Some examples related to the most critical functions will be included.
MOPLT016	Upgrade and Tests of the SPS Fast Extraction Kicker System for LHC and CNGS	extraction, simulation, proton, diagnostics	566
	E.H.R. Gaxiola, A. Antoine, P. Burkel, E. Carlier, F. Castronuovo, L. Ducimetière, Y. Sillanoli, M. Timmins, J.A. Uythoven CERN, Geneva
	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 simulated and measured kick characteristics of the upgraded system are presented, along with results from uniformity calculations of the magnetic field after the modifications to accommodate the cooling circuitry. Further improvements will be discussed which are intended to make the system comply with the specifications for CNGS.
MOPLT017	Beam Commissioning of the SPS LSS4 Extraction and the TT40 Transfer Line	extraction, septum, controls, instrumentation	569
	B. Goddard, P. Collier, M. Lamont, V. Mertens, K. Sigerud, J.A. Uythoven, J. Wenninger CERN, Geneva
	The new fast extraction system in LSS4 of the SPS and the transfer line TT40 were installed between 2000 and 2003, and commissioned with beam in late 2003. The extraction system and transfer line will serve both the anti-clockwise ring of the Large Hadron Collider (LHC), and the long baseline neutrino (CNGS) facility. The layout and functionality of the main elements are briefly explained, including the various hardware subsystems and the controls system. The safety procedures, test objectives and results of the system commissioning with beam are described, together with the test methodology. Conclusions are drawn concerning the performance of the system elements, agreement between predicted and expected activation levels and test efficiency and procedures. The test results are also briefly discussed in the context of future LHC beam commissioning activities.
MOPLT018	Aperture and Delivery Precision of the LHC Injection System	injection, extraction, vacuum, quadrupole	572
	B. Goddard, M. Gyr, J.-B. Jeanneret, V. Kain, M. Lamont, V. Maire, V. Mertens, J. Wenninger CERN, Geneva
	The main LHC injection elements in interaction regions 2 and 8 comprise the injection septa (MSI), the injection kicker (MKI), together with three families of passive protection devices (TDI, TCDD and TCLI). The apertures of the injection septa for the injected and two circulating beams are detailed with a new enlarged vacuum chamber and final septum alignment. The circulating beam aperture of the TDI is detailed with a new TDI support design and modified vacuum tank alignment. A modified TCDD shape is also presented and the implications for the aperture and protection level discussed. The various errors in the SPS, the transfer lines and the injection system, which contribute to injection errors, are analysed, and the expected performance of the system is derived, in terms of the expected delivery precision of the injected beam.
MOPLT022	The Expected Performance of the LHC Injection Protection System	injection, simulation, proton, insertion	584
	V. Kain, O.S. Brüning, L. Ducimetière, B. Goddard, M. Lamont, V. Mertens CERN, Geneva
	The passive protection devices TDI, TCDD and TCLI are required to prevent damage to the LHC in case of serious injection failures, in particular of the MKI injection kicker. A detailed particle tracking, taking realistic mechanical, positioning, injection, closed orbit and local optical errors into account, has been used to determine the required settings of the absorber elements to guarantee protection against different MKI failure modes. The expected protection level of the combination of TDI with TCLI, with the new TCLI layout, is presented. Conclusions are drawn concerning the expected damage risk level.
MOPLT034	Possible Causes and Consequences of Serious Failures of the LHC Machine Protection System	dumping, extraction, injection, quadrupole	620
	J.A. Uythoven, R. Filippini, B. Goddard, M. Gyr, V. Kain, R. Schmidt, J. Wenninger CERN, Geneva
	The LHC machine protection systems, including the beam dumping system, are designed to ensure that failures leading to serious damage to the LHC during its lifetime are extremely unlikely. These kind of failures have to date been considered as being ?beyond the design case?, for instance requiring a combination of equipment failure and surveillance failure. However, they need to be evaluated to determine the required safety levels of the protection systems. A second objective is to understand if measures can and should be taken to further reduce the probability of such failures, or to minimise their impact. This paper considers various serious failure modes of the different machine protection systems. The probable consequences and possible ameliorating measures of the worst-case scenarios are discussed. The particular case of having a stored beam with an unavailable beam dumping system is mentioned, together with possible actions to be taken in such an event.
MOPLT035	Beam Induced Heating of the SPS Fast Pulsed Magnets	impedance, extraction, injection, vacuum	623
	J.A. Uythoven, G. Arduini, T. Bohl, F. Caspers, E.H.R. Gaxiola, T. Kroyer, M. Timmins, L. Vos CERN, Geneva
	Fast pulsed magnets with ferrite yokes are used in CERN?s SPS accelerator for beam injection, extraction and excitation for tune measurements. The impedance of the ferrite structures can provoke significant beam induced heating, especially for beams with high peak currents as for LHC operation, even beyond the Curie temperature. The expected heating in the different kicker systems for various operational modes is compared with beam measurements. Estimates of the beam induced power have been derived from measured beam spectra. A fast extraction kicker system has recently been equipped with a cooling system. The measured cooling performance is compared with data from laboratory setups and numerical simulations.
MOPLT037	Simulation of Transient Beam-feedback Interaction with Application to the Extraction of the CNGS Beam from the SPS	extraction, feedback, betatron, simulation	626
	E. Vogel, W. Höfle CERN, Geneva
	For actual and future high energy proton accelerators, such as the LHC, transverse feedback systems play an essential role in supplying the physics experiments with high intensity beams at low emittances. We developed a simulation model to study the interaction between beam and transverse feedback system in detail, bunch-by-bunch and turn-by-turn, considering the real technical implementation of the latter. A numerical model is used as the nonlinear behavior (saturation) and limited bandwidth of the feedback system, as well as the transient nature at injection and extraction, complicates the analysis. The model is applied to the practical case of the CNGS beam in the SPS accelerator. This beam will be ejected from the SPS in two batches causing residual oscillations by kicker ripples on the second batch. This second batch continues to circulate for some 1000 turns after the first batch has been extracted and oscillations are planned to be damped by the feedback system. It is shown how the model can be extended to the case of transients at injection (LHC), and to include coupled bunch instability effects.
MOPLT069	Investigation of Injection for the Low-emittance Lattice with New-6.25 ohm Kicker Magnet System at the Photon Factory	injection, factory, lattice, photon	710
	A. Ueda, K. Harada, Y. Kobayashi, T. Mitsuhashi KEK, Ibaraki
	We installed 6.25ohm traveling-wave kicker magnet in the Photon Factory to obtain a wide acceptance for the injected beam into the low-emittance lattice of the Photon Factory. We investigate the injection for the low-emittance lattice with this 6.25ohm kicker magnet system. Hence we have optical beam diagnostic systems which source point is inside of injection bump, we use this system for the investigation of injection. The pulse shape of the injection bump was measured by the optical beam profile monitor with high-speed gated camera by using a stored beam. The result of pulse shape of injection bump was agreed with the predicted one by using result of magnetic field measurement, and pulse duration was shorter than twice of revolution time. The instantaneous beam profile of injected beam was observed in turn by turn by using the same beam profile monitor system. We measure the turn by turn position of the injected beam from this observation and compare with a simulation. We also observe a smear out of beam oscillation by nonlinear effect from this instantaneous beam profile measurement.
MOPLT070	FFAG as Phase Rotator for the PRISM Project	synchrotron, simulation, lattice, injection	713
	A. Sato, M. Aoki, Y. Arimoto, Y. Kuno, M. Yoshida Osaka University, Osaka Y. Iwashita Kyoto ICR, Uji, Kyoto S. Machida, Y. Mori, C. Ohmori, T. Yokoi, K. Yoshimura KEK, Ibaraki S. Ninomiya RCNP, Osaka
	A Fixed Field Alternating Gradient (FFAG) ring will be used as a phase rotator in the PRISM project. We report a design of the PRISM-FFAG in this paper. PRISM stands for "Phase Rotated Intense Slow Muon beam". It is a project to realize a super muon beam, which combines high-intensity, low-energy, narrow energy-spread and high purity. Its aimed intensity is about 1011-1012 muons per sec. The muon beam will be provided with a low kinetic energy of 20MeV to optimize for the stopped muon experiments. FFAG has some advantageous characteristics to achieve such superb beam. These are a large momentum (longitudinal) acceptance, a wide transverse acceptance with strong focusing, and synchrotron oscillation, which is needed to perform phase rotation. According to simulations, initial energy spread of 20MeV±40% is reduced down to ±6% after 5 turns of muons in the FFAG ring. In the FFAG ring almost all pions decay into muon, hence extracted beam has extremely low pion contamination. A program to construct the PRISM-FFAG ring has been started. It would be completed by the end of JFY 2005.
MOPLT089	SOS-diode Based Pulser for the Injection System of the Collider VEPP-2000	injection, collider, positron, electron	743
	F.V. Podgorny, B.I. Grishanov, A.S. Kasaev BINP SB RAS, Novosibirsk
	We describe high voltage pulsers for supplying of kickers of the collider VEPP-2000 injection system. The high voltage pulse is formed as a result of a sharp break of a high current, accumulated previously in storage elements, by means SOS-diode. Pulse forming lines or inductances could be used as the storage elements. The generators form the quasi-rectangular pulses on the 50-Ohm load. The generator scheme is described also.
MOPLT107	Nanosecond-timescale Intra-bunch-train Feedback for the Linear Collider: Results of the FONT2 Run	feedback, linear-collider, collider, dipole	785
	P. Burrows, T. Hartin, S.M. Hussain, S. Molloy, G.R. White Queen Mary University of London, London C. Adolphsen, J.C. Frisch, L. Hendrickson, R.K. Jobe, T. Markiewicz, D.J. McCormick, J. Nelson, M.C. Ross, S. Smith, T.J. Smith SLAC, Menlo Park, California R. Barlow, M. Dufau, A. Kalinin CCLRC/DL/ASTeC, Daresbury, Warrington, Cheshire G. Myatt, C. Perry OXFORDphysics, Oxford, Oxon
	We report on experimental results from the December 2003/January 2004 data run of the Feedback On Nanosecond Timescales (FONT) experiment at the Next Linear Collider Test Accelerator at SLAC. We built a second-generation prototype intra-train beam-based feedback system incorporating beam position monitors, fast analogue signal processors, a feedback circuit, fast-risetime amplifiers and stripline kickers. We applied a novel real-time charge-normalisation scheme to account for beam current variations along the train. We used the system to correct the position of the 170 nanosecond-long bunchtrain at NLCTA, in both 'feed forward' and 'feedback' modes. We achieved a latency of 53 nanoseconds, representing a significant improvement on FONT1 (2002), and providing a demonstration of intra-train feedback for the Linear Collider.
MOPLT127	Diagnosing the PEP-II Injection System	injection, septum, luminosity, background	833
	F.-J. Decker, M.H. Donald, R.H. Iverson, A. Kulikov, G.C. Pappas, M. Weaver SLAC, Menlo Park, California
	The injection of beam into the PEP-II B-Factory, especially into the High Energy Ring (HER) has some challenges. A high background level in the BaBar Detector has so far inhibited us from trickling charge into the HER similar to the Low Energy Ring (LER). Analyzing the injection system has revealed many issues which could be improved. The injection bump between two kickers was not closed, mainly because the phase advance wasn't exactly 180 degrees and the two kicker strengths were not balanced. Additionally we found reflections which kick the stored beam after the main kick and cause the average luminosity to drop about 3% for a 10 Hz injection rate. The strength of the overall kick is nearly twice as high than the design, indicating a much bigger effective septum thickness. Compared with single beam the background is worse when the HER beam is colliding with the LER beam. This hints that the beam-beam force and the observed vertical blow-up in the HER pushes the beam and especially the injected beam further out to the edge of the dynamic aperture or beyond.
MOPLT177	Stochastic Cooling Power Requirements	emittance, betatron, pick-up, luminosity	941
	J. Wei, M. Blaskiewicz, J.M. Brennan BNL, Upton, Long Island, New York
	A practical obstacle for stochastic cooling in high-energy colliders is the large amount of power needed for the cooling system. This paper discusses the cooling power needed for the longitudinal cooling process. Based on the coasting-beam Fokker-Planck equation, we analytically derived the optimum cooling rate and cooling power for a beam of uniform distribution and a cooling system of linear gain function. The results indicate that the usual back-of-envelope formula over-estimated the cooling power by a factor of the mixing factor $M$. On the other hand, the scaling laws derived from the coasting-beam Fokker-Planck approach agree with those derived from the bunched-beam Fokker-Planck approach if the peak beam intensity is used as the effective coasting-beam intensity. A longitudinal stochastic cooling system of 4 – 8 GHz bandwidth in RHIC can effectively counteract intrabeam scattering, preventing the beam from escaping the RF bucket becoming debunched around the ring.
TUXLH01	Machine Protection Issues and Strategies for the LHC	beam-losses, injection, proton, insertion	88
	R. Schmidt, J. Wenninger CERN, Geneva
	For nominal beam parameters at 7 TeV/c, each of the two LHC proton beams has a stored energy of 350 MJ threatening to damage accelerator equipment in case of uncontrolled beam loss. Since the beam dump blocks are the only element of the LHC that can withstand the impact of the full beam, it is essential for the protection of the LHC that the beams are properly extracted onto the dump blocks in case of emergency. The time constants for failures leading to beam loss extend from 100 microseconds to few seconds. Several protection systems are designed to ensure safe operation, such as beam instrumentation, collimators and absorbers, and magnet protection. Failures must be detected at a sufficiently early stage and transmitted to the beam interlock system that triggers the beam dumping system. The strategy for the protection of the LHC will be illustrated starting from some typical failures.
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TUPLT008	A Retrofit Technique for Kicker Beam-coupling Impedance Reduction	impedance, simulation, resonance, extraction	1144
	F. Caspers, E.H.R. Gaxiola, T. Kroyer, M. Timmins, J.A. Uythoven CERN, Geneva S.S. Kurennoy LANL/LANSCE, Los Alamos, New Mexico
	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.
TUPLT077	R&D Status of the Fast Extraction Kicker Magnets for the KEK/JAERI 50 GeV Synchrotron	ion, septum	1333
	Y. Shirakabe, Y. Arakaki, T. Kawakubo, Y. Mori, S. Murasugi, E. Nakamura, I. Sakai, M. Tomizawa KEK, Ibaraki
	The 50 GeV proton synchrotron composes the final stage of the high intensity proton accelerator complex now on construction at JAERI/Tokai site as a joint project by KEK and JAERI. In this ring, the proton beam is accelerated from 3 GeV to 50 GeV, and delivered to the experimental facilities through the fast and slow extraction lines. The distinctive feature of the fast extraction line is that the bipolar extraction function will be provided. In normal operations, the beam is extracted toward the inner side of the ring and transported to the facility for the long baseline neutrino oscillation experiment using the Super-Kamiokande detector. In case of emergency, for example, quenches of the superconducting magnets of the neutrino line or malfunctioning of the ring RF systems, the beam is extracted toward the outer side of the ring and sent directly to the abort line with a beam dump at the end. In the current kicker design, the bipolar function will be achieved by the Symmetric Blumlein PFN (SBPFN) system with two switches on both ends. The designed parameters of the fast extraction kicker magnets and the recent hardware R&D status will be described in this paper.
TUPLT078	Study of Impedances and Instabilities in J-PARC	impedance, vacuum, resonance, synchrotron	1336
	T. Toyama, K. Ohmi KEK, Ibaraki Y. Shobuda JAERI/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken
	J-PARC consists of two high intensity proton rings with energies of 3 GeV and 50 GeV. Longitudinal impedances and instabilities, which are caused by beam chamber, cavities, kicker magnets and others, are mainly discussed in this paper.
TUPLT099	A Kicker Pulse Power Supply with Low Jitter	power-supply, injection, storage-ring, booster	1387
	C.-S. Fann, J.-P. Chiou, S.Y. Hsu, K.-B. Liu NSRRC, Hsinchu
	The performance of kicker pulse power supplies is the main parameter to increase injection efficiency of storage ring that is an important issue for laboratory of synchrotron radiation research. The output current waveform of a kicker pulse power supply with low timing jitter is our goal for years that must satisfy the Top-Up mode injection requirement of NSRRC. In the past years kicker pulse power supplies of storage ring of NSRRC are immersed in isolation oil to sustain high voltage operational environment that led difficult to maintain, electronic component degrading and uneasy to tune parameters. Air-cooling and air-isolation is adopted in the new design structure for kicker pulse power supply system and an pre-trigger unit MA2709A is installed to trigger thyratron tube CX1536A, a kicker pulse power supply with low timing jitter 1~2ns(p-p) is obtained and could satisfy for Top-Up mode injection and maintenance is more easier than before.
TUPLT103	Possibilities for Experiments with Rare Radioactive Ions in a Storage Ring Using Individual Injection	ion, injection, electron, target	1393
	A.O. Sidorin, I.N. Meshkov, A.O. Sidorin, A. Smirnov, E. Syresin, G.V. Troubnikov JINR, Dubna, Moscow Region T. Katayama CNS, Saitama W. Mittig, P. Roussel-Chomaz GANIL, Caen
	A radioactive ion beam produced at a target bombarded with a primary beam has after a fragment separator a relatively large emittance and small production rate. For instance, typical flux of 132Sn isotope at the exit of fragment-separator is about 5×105 ions/s. Conventionally used scheme of the ion storage in a ring based on multitutrn injection and (or) RF stacking and stochastic cooling application can not provide a high storage rate at so pure intensity especially for short lived isotopes. In this report we discuss an alternative storage scheme which is oriented to the continuous ion beam from fragment separator at production rate of 104 ions/s or even less. It is based on the fact, that at low production rate the parameters of each particle can be measured individually with rather high accuracy. The particle trajectory can be individually corrected in a transfer channel from fragment separator to the storage ring using system of fast kickers. A fast kicker in the ring synchronized with a circulating bunch provides continuous injection of the ions. The scheme permits to store the ion number required for precise mass measurements and internal target experiment. A hope to obtain large luminosity of ion-electron collisions is related with a possibility of the ion beam crystallization at small particle number.
TUPLT104	Particle Dynamics in the Low Energy Positron Toroidal Accumulator: First Experiments and Results	electron, positron, septum, quadrupole	1396
	G.V. Troubnikov, V. Antropov, E. Boltushkin, V. Bykovsky, A.I. Ivanov, S. Ivashkevich, A. Kobets, I.I. Korotaev, V. Lohmatov, I.N. Meshkov, D. Monahov, V. Pavlov, R. Pivin, I.A. Seleznev, A.O. Sidorin, A. Smirnov, E. Syresin, S. Yakovenko JINR, Dubna, Moscow Region
	The project of Low Energy Particle Toroidal Accumulator (LEPTA) is dedicated to construction of a positron storage ring with electron cooling of positrons circulating in the ring. Such a peculiarity of the LEPTA enables it automatically to be a generator of positronium (Ps) atoms, which appear in recombination of positrons with cooling electrons inside the cooling section of the ring. The project has a few goals: to study electron and positron dynamics in the ring (particle motion in the horizontal and vertical planes are coupled contrary to of classic cycle accelerators), to set up first experiments with Ps in flight; Magnetic measurements of main LEPTA elements are performed. Several elements : kicker, injection system of electron beam, helical quadrupole, septum magnet are tested and expected design parameters were achieved for those elements. The investigations of electron beam dynamics are started. First results of experiments with circulating electron beam are presented and discussed in this article. Several beam diagnostic methods for studying of strong coupled motion of charged particles are proposed and tested.
TUPLT154	Aperture Studies for the Fermilab AP2 Anti-proton Line	lattice, antiproton, injection, chromatic-effects	1491
	I. Reichel, M. Placidi, M.S. Zisman LBNL, Berkeley, California K. Gollwitzer, S. Werkema Fermilab, Batavia, Illinois
	The AP2 beamline transports anti-protons from the production target to the Debuncher ring. In the past the observed aperture has been smaller than that estimated from linear, on-energy optics. We have investigated possible reasons for the aperture limitation and have identified possible sources, including residual vertical dispersion from alignment errors and chromatic effects due to very large chromatic lattice functions. Some experiments have already been performed to study these effects. We present results of the experimental and theoretical studies and possible remedies.
TUPLT170	The SNS Beam Power Upgrade	linac, extraction, space-charge, klystron	1527
	S. Henderson, S. Assadi, R. Cutler, V.V. Danilov, G.W. Dodson, R.E. Fuja, J. Galambos, J.A. Holmes, N. Holtkamp, D.-O. Jeon, S. Kim, L.V. Kravchuk, M.P. McCarthy, G.R. Murdoch, D.K. Olsen, T.J. Shea, M.P. Stockli ORNL/SNS, Oak Ridge, Tennessee
	The Spallation Neutron Source (SNS) accelerator systems, which consist of an H- injector, a 1 GeV linear accelerator, an accumulator ring and associated transport lines, will provide a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron production. The SNS is presently under construction at Oak Ridge National Laboratory and will begin operations in 2006. Even in the baseline design, many of the accelerator subsystems are capable of supporting higher beam intensities and higher beam energy. We report on upgrade scenarios for the SNS accelerator systems which increase the 1.44 MW baseline beam power to at least 3 MW, and perhaps as high as 5 MW. The increased SNS beam power can be achieved primarily by increasing the H- ion source current, installing additional superconducting cryomodules to increase the final linac beam energy to 1.3-1.4 GeV, and modifying injection and extraction hardware in the ring to handle the increased beam energy. The upgrade beam parameters will be presented, the required hardware modifications will be described, and the beam dynamics implications will be discussed.
TUPLT187	SNS Extraction Kicker Power Supply Control	power-supply, extraction, proton, controls	1568
	J.-L. Mi, L. Hoff, R.F. Lambiase, Y.Y. Lee, J. Sandberg, Y. Tan, N. Tsoupas, R. Zapasek, W. Zhang BNL, Upton, Long Island, New York
	There are fourteen PFN power supplies, which will be installed in the SNS Extraction Kicker System. This paper will introduce these fourteen-power supplies arrangement and control schematic. These control instruments and boards are installed into four standard racks. Some of the control boards functions will be list in this paper. Control racks and some control boards pictures will be shown in this paper.
TUPLT188	SNS Extraction Kicker Power Supply Manufacture Status	power-supply, extraction, impedance, coupling	1571
	J.-L. Mi, H. Hahn, R.F. Lambiase, Y.Y. Lee, C. Pai, J. Sandberg, Y. Tan, N. Tsoupas, D.S. Warburton, R. Zapasek, W. Zhang BNL, Upton, Long Island, New York
	There are fourteen PFN power supplies, which will be installed in the SNS Extraction Kicker System. The Pulse Forming Network (PFN) power supplies for the SNS Extraction kicker were designed by Brookhaven. The basic configuration of the PFN is a lumped element Blumlein pulse forming network (BPFN). The PFN and power supply are fabricated by an industrial company. The first article of. PFN and power supply has been manufactured and tested with a dummy load at the company and onsite with the prototype magnet. The PFN has been tested beyond its specification and has met all requirements including rise time, pulse flatness, amplitude and pulse repetition rate. Additional heat runs are scheduled. The transverse coupling impedance of the kicker system with attached PFN has been measured. This paper will report on the SNS Extraction Kicker Power Supply engineering status, and will include output waveforms, impedance measurements, and production projections.
WEOCCH02	Construction Status and Issues of the Spallation Neutron Source Ring	injection, extraction, dipole, vacuum	156
	J. Wei BNL, Upton, Long Island, New York
	(For the Spallation Neutron Source collaboration) The Spallation Neutron Source (SNS) accelerator complex is now in its sixth year of a seven-year construction cycle. The design, fabrication, test, and assembly of the accumulator ring and its transport lines is approaching the final stage. In order to reach the design goal of this high-power ring to deliver 1.5 MW beam power (1.5$× 1014 protons of 1 GeV kinetic energy at a repetition rate of 60 Hz), stringent measures have been implemented to ensure the quality of the accelerator systems. This paper reviews the progress of the ring and transport systems with emphasis on the challenging technical issues and their solutions inccurred during the construction period.
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WEPKF026	Kicker Pulser with High Stability for the BESSY FEL	laser, power-supply, extraction, electron	1654
	J. Feikes, O. Dressler, J. Kuszynski BESSY GmbH, Berlin
	In the BESSY FEL design a kicker system is forseen to extract electron bunches from the main LINAC into two FEL beam lines, beside the straigth main beamline. Sine half wave pulsers with a repetion rate of up to 1 kHz and modest pulse currents of 120A will be used. To receive the maximum FEL gain, it is crucial, that the extracted bunches enter well centered into the undulators. Hence, the extraction demands for very high short-term stability of the magnetic field (shot to shot). A kicker pulse amplitude with a relative amplitude jitter smaller than 5* 10-5 would be tolerable ?more than one order smaller than the jitter of conventional BESSY II kicker systems in use. A new highly stable semiconductor based kicker pulser prototype was designed, built and tested at BESSY. It was shown that the stability of the pulse current fulfills the FEL requirements. The pulser design, its layout and the corresponding pulse current jitter measurements are presented.
WEPKF068	Developments in Magnet Power Converters at the SRS	power-supply, booster, septum, storage-ring	1759
	G.D. Charnley, J. Cartledge, P.A.D. Dickenson, S.A. Griffiths, S.H. Hands, R.J. Smith, J.E. Theed, C.J. White CCLRC/DL, Daresbury, Warrington, Cheshire
	A project to upgrade the magnet power converters of the SRS has commenced to ensure its efficient operation for its remaining operational lifetime. A recent risk analysis of the facilities equipment identified that the main areas for concern were the Storage Ring magnet power converters, kicker and septum pulse power supplies and the Booster Dipole "White Circuit" and associated power converters. This report detail the development and replacement programs currently active at Daresbury Laboratory, including future work identified to support and improve SRS utilisation.
WEPKF079	A Kicker Design for the Rapid Transfer of the Electron Beam between Radiator Beamlines in LUX	electron, septum, linac, injection	1786
	G.D. Stover LBNL/ALS, Berkeley, California
	I present in this paper preliminary design concepts for LUX - A ?fast kicker design for rapid transfer of the electron beam between radiator beamlines. This paper is a very simple feasibility study to find a rougly optimized subset of engineering parameters that would satisfy the initial design specifications of: Pulse width < 30us, time jitter < 1ns, magnetic length < 0.5meter, gap hight = 15mm, gap width = 25mm, peak field = .6Tesla, bend angle = 1.7 deg. for beam energy of 3.1 Gev, repetition rate = 10KHz. An H magnet core configuration was chosen. Through an iterative mathematical process a realizable design was chosen. Peak current, Peak voltages across the coils, conductor losses due to proximity and skin effects, di/dt rates, eddy and beam current heating in the ceramic vacuum chamber, and basic circuit topology were investigated. Types and losses of core material were only briefly discussed. The final topology consists of two magnets in series running at 10KHz, .3Tesla, 630 amp peak current, 10us pulse width, 364 Watts per coil section, driven by fast solid state switch with an energy recovery inductor. Eddy and beam image current losses were ~ 164 watts.
WEPKF087	SNS Extraction Fast Kicker Pulsed Power System	extraction, impedance, pulsed-power, vacuum	1810
	W. Zhang, H. Hahn, J.-L. Mi, C. Pai, J. Sandberg, Y. Tan, N. Tsoupas, J. Tuozzolo, D.S. Warburton, J. Wei BNL, Upton, Long Island, New York R. Cutler, K. Rust ORNL/SNS, Oak Ridge, Tennessee
	The Spallation Neutron Source (SNS) is a next generation high intensity beam facility. Its Accumulator Ring Extraction Fast Kicker System is a very high peak power, high average power, high precision pulse-waveform, ultra-low beam impedance, and high repetition rated pulsed power system. It has been successfully design and developed at Brookhaven National Laboratory. This system will consist of fourteen identical high voltage modulators and fourteen extraction magnet sections located inside of the SNS accumulator ring. The overall system output will reach multiple GW peak power with 60 Pulse-per-second repetition rates. The techniques of reducing impedance, improving rise time, and minimizing ripples will be discussed. The lifetime considerations, issues of the system design, development and construction are presented in this paper.
WEPLT036	Energy Loss of a Single Bunch in the CERN SPS	impedance, single-bunch, beam-loading, pick-up	1909
	E.N. Shaposhnikova, T. Bohl, T.P.R. Linnecar, J. Tuckmantel CERN, Geneva A. Hofmann Honorary CERN Staff Member, Grand-Saconnex
	The dependence of energy loss on bunch length was determined experimentally for a single proton bunch in the SPS at 26 GeV/c. This was done from measurements of the synchronous phase as a function of intensity for different capture voltages. The results are compared with the expected dependence calculated from the resistive part of the SPS impedance below 1 GHz. Two impedance sources, the cavities of the 200 MHz RF system and the extraction kickers, give the main contributions to particle energy loss in very good agreement with experiment. The results obtained allow a better understanding of some mechanisms leading to capture loss of the high intensity LHC beam in the SPS.
WEPLT084	Experimental Frequency Maps for the ESRF Storage Ring	resonance, storage-ring, dynamic-aperture, optics	2050
	Y. Papaphilippou, L. Farvacque, E. Plouviez, J.-L. Revol, A. Ropert ESRF, Grenoble J. Laskar IMCCE, Paris Ch. Skokos Academy of Athens, Athens
	Experimental frequency maps have already revealed many unknown characteristics of the ESRF storage ring non-linear dynamics. In the past year, several efforts were undertaken in order to establish this technique as an operational on-line tool. The acquisition time was significantly reduced by collecting data from a dedicated fast BPM system. The problem of beam decoherence was limited by establishing a method for accurate tune determination in a small number of turns, using the information from all the BPMs around the ring. The possibility to explore the off-momentum dynamics by exciting the beam, with synchronous transverse and longitudinal kicks was also investigated. Finally, measurements of resonance driving term amplitudes and phase advances were used to identify the efficiency of resonance corrections.
WEPLT143	Simulation Calculations of Stochastic Cooling for Existing and Planned GSI Facilities	ion, antiproton, pick-up, simulation	2170
	I. Nesmiyan National Taras Shevchenko University of Kyiv, Radiophysical Faculty, Kiev F. Nolden GSI, Darmstadt
	The process of longitudinal stochastic cooling is simulated using a Fokker-Planck model. The model includes the sensitivities of pick-up and kicker electrodes as calculated from field theoretical models. The effect of feedback through the beam is taken into account. Intra beam scattering is treated as an additional diffusive effect. The calculations cover the existing system of the ESR storage ring at GSI as well as the cooling system for secondary heavy ion and antiproton beams at the proposed new accelerator facility. The paper discusses the resulting cooling times. Requirements on the system layout as amplification factors and electrical power can be derived from the simulations.
THPLT019	Commissioning Results of the Multi Bunch Feedback System at SLS	feedback, diagnostics, storage-ring, betatron	2508
	M. Dehler, R. Kramert, P. Pollet, T. Schilcher PSI, Villigen D. Bulfone, M. Lonza ELETTRA, Basovizza, Trieste
	Within the frame of the project for a multi bunch feedback system for the Swiss Light Source (SLS), a new family of 500 MS/s analog to digital and digital to analog conversion boards with an 8 bit resolution has been developed, containing on board MUX and DEMUX circuitry to reduce data rates to approximately 20 MS/s using up to ten Front Panel Data Port (FPDP) ports. Using six quad processor DSP boards, full bandwidth bunch by bunch feedbacks in the transverse and longitudinal planes are set up to provide bunch by bunch correction kicks with a 2 nsec resolution. We report on the hardware setup and properties as well as feedback performance in the SLS storage ring.
THPLT066	Commissioning of 150MeV FFAG Synchronisation	injection, septum, extraction, acceleration	2643
	Y. Yonemura, M. Matoba Kyushu University, Fukuoka M. Aiba, M. Sugaya University of Tokyo, Tokyo S. Machida, Y. Mori, A. Muto, J. Nakano, C. Ohmori, I. Sakai, Y. Sato, A. Takagi, T. Yokoi, M. Yoshii, M. Yoshimoto, Y. Yuasa KEK, Ibaraki T. Uesugi NIRS, Chiba-shi A. Yamazaki LNS, Sendai
	A 150MeV proton FFAG (Fixed Field Alternating Gradient) synchrotron has been constructed to be a prototype for various applications such as proton beam therapy. At the moment, all the components are assembled, and multi-turn injection and beam storage were successfully performed. We are in the phase of beam acceleration up to final energy and expect the beam extraction in a few months. In this paper, beam commissioning results such as multi-turn injection, orbit correction, tune survey and optimization of RF gymnastics will be presented.
THPLT069	High Speed Beam Loss Monitor and its Deterioration by Radiation	beam-losses, radiation, septum, booster	2652
	T. Kawakubo, T. Ishida, T. Sanami KEK, Ibaraki
	High speed loss monitor is very useful for tuning and operating the beam in an accelerator, especially in the injection and extraction period. We made a new type loss monitor by connecting a fiber to a photo-multiplier (PMT). In the case that the fiber is made of quartz, the source of the signal is Cherenkov effect. And in the case of scintillation fiber, the signal comes from the scintillation effect. The quartz is much stronger than the scintillator to the radiation, but generating light in the quartz is weaker than scintillator, especially in low energy beam. It is very easy to make this monitor and the fabrication cost is cheap. The monitor can observe the bunch loss with an order of 10 ns. After long time use under high irradiation, the signal of the monitor will decrease. Therefore, we also report the dependence of the signal strength on accumulated radiation in various types of material.
THPLT137	Commissioning of the Head-tail Monitoring Application for the Tevatron	synchrotron, proton, acceleration, monitoring	2780
	V.H. Ranjbar, V. Lebedev, E. Lorman, A. Xiao Fermilab, Batavia, Illinois
	A head-tail beam monitoring application has recently been developed for use in the Tevatron. With this application beam dynamics problems including head-tail instabilities can be monitored. In addition it can be use to perform chromaticity measurements using the head-tail technique developed at CERN. This application speeds up chromaticity measurements in the Tevatron especially during the acceleration ramp and low beta squeeze, which previously required three separate ramps using uncoalesced protons
THPLT153	Commissioning and Initial Operation of the Isotope Production Facility at the Los Alamos Neutron Science Center	target, isotope-production, diagnostics, beam-losses	2816
	K.F. Johnson, H.W. Alvestad, W.C. Barkley, D.B. Barlow, D.S. Barr, G.A. Bennett, L.J. Bitteker, E. Bjorklund, W. Boedeker, M.J. Borden, R.A. Cardon, G. Carr, J.L. Casados, S. Cohen, J.F. Cordova, J.A. Faucett, M. Fresquez, F.R. Gallegos, J.D. Gilpatrick, F. Gonzales, F.W. Gorman, M.S. Gulley, M.J. Hall, D.J. Hayden, R.C. Heaton, D. Henderson, D.B. Ireland, G. Jacobson, G.D. Johns, D.M. Kerstiens, A.J. Maestas, A.R. Martinez, D. Martinez, G.C. Martinez, J. Martinez, M.P. Martinez, R. Merl, J.B. Merrill, J. Meyer, M.L. Milder, E.A. Morgan, F.M. Nortier, J.F. O'Hara, F.R. Olovas, M.A. Oothoudt, T.D. Pence, E.M. Perez, C. Pillai, F.P. Romero, C. Rose, L. Rybarcyk, G. Sanchez, J.B. Sandoval, S. Schaller, F.E. Shelley, R.B. Shurter, W. Sommer, M.W. Stettler, J.L. Stockton, J. Sturrock, T.L. Tomei, V.P. Vigil, P.L. Walstrom, P.M. Wanco, J. Wilmarth LANL/LANSCE, Los Alamos, New Mexico R.E. Meyer, E.J. Peterson, F.O. Valdez LANL, Los Alamos, New Mexico
	The recently completed 100-MeV H+ Isotope Production Facility (IPF) at the Los Alamos Neutron Science Center (LANSCE) will provide radioisotopes for medical research and diagnosis, for basic research and for commercial applications. A change to the LANSCE accelerator facility allowed for the installation of the IPF. Three components make up the LANSCE accelerator: an injector that accelerates the H+ beam to 750-KeV, a drift-tube linac (DTL) that increases the beam energy to 100-MeV, and a side-coupled cavity linac (SCCL) that accelerates the beam to 800-MeV. The transition region, a space between the DTL and the SCCL, was modified to permit the insertion of a kicker magnet (23o kick angle) for the purpose of extracting a portion of the 100-MeV H+ beam. A new beam line was installed to transport the extracted H+ beam to the radioisotope production target chamber. This paper will describe the commissioning and initial operating experiences of IPF.
THPLT163	High-temperature Kicker Electrodes for High-beam-current Operation of PEP-II	impedance, feedback, vacuum, radiation	2843
	U. Wienands, R. Akre, D.E. Anderson, S. Debarger, K. Fant, D. Kharakh, R.E. Kirby, A. Krasnykh, A. Kulikov, J. Langton SLAC, Menlo Park, California
	The strip line electrodes of the kickers used in the transverse bunch-by-bunch feedback systems see significant power deposition by beam and HOM-induced currents. This leads to elevated temperatures of the aluminum electrodes and will ultimately become a limit for the beam current in the Low Energy Ring. Heat is transported to the environment primarily by radiation from the blackened surface of the electrodes. In order to extend the beam-current range of these kickers, new electrodes have been fabricated from molybdenum which are able to run at significantly higher temperature, thus greatly increasing the efficiency of the radiative cooling of the electrodes. Blackening of the electrodes is achieved by oxidation in air at 1000°F using a recipe first applied in aviation research for supersonic aircraft. Emissivity was measured on coupons and a whole electrode to be about 0.6. In addition, the match at the terminations of the electrodes is improved following field calculations and measurements on a model of the kicker.
THPLT171	Stochastic Cooling Studies in RHIC, II	scattering, pick-up, feedback, proton	2861
	M. Blaskiewicz, J.M. Brennan, J. Wei BNL, Upton, Long Island, New York
	Intra-beam scattering is unavoidable for highly charged heavy ions and causes emittance growth during the store for collision physics. A longitudinal bunched beam stochastic cooling system will confine the bunch within the RF bucket increasing the useful luminosity. A single bunch, Palmer cooling system is under investigation. We present data and compare them with theory.