Download or read book Transient Beam Loading in the ALS Harmonic RF System written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on the commissioning of a higher harmonicradiofrequency system at the Advanced Light Source, designed to improvethe beam lifetime. We have achieved an increase above a factor of two inour best results up to now. Transient beam loading of the harmoniccavities, due to the unequal fill patterns, creates the greatestlimitation on lifetime improvement. We also describe several interestingeffects on the operation of the longitudinal and transverse multibunchfeedback system.
Download or read book Transient Beam Loading Effects in RF Systems in Jleic written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The pulsed electron bunch trains generated from the Continuous Electron Beam Accelerator Facility (CEBAF) linac to inject into the proposed Jefferson Lab Electron Ion Collider (JLEIC) e-ring will produce transient beam loading effects in the Superconducting Radio Frequency (SRF) systems that, if not mitigated, could cause unacceptably large beam energy deviation in the injection capture, or exceed the energy acceptance of CEBAF's recirculating arcs. In the electron storage ring, the beam abort or ion clearing gaps or uneven bucket filling can cause large beam phase transients in the (S)RF cavity control systems and even beam loss due to Robinson instability. We have first analysed the beam stability criteria in steady state and estimated the transient effect in Feedforward and Feedback RF controls. Initial analytical models for these effects are shown for the design of the JLEIC e-ring from 3GeV to 12GeV.
Download or read book Static and Transient Beam Loading of a Synchrotron written by and published by . This book was released on 1992 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a synchrotron, when the beam induced current is comparable to the driver current, the RF cavity is subjected to beam loading perturbation and corrective steps have to be implemented to regain beam stability. In this paper, the static and transient beam loading will be studied. We first discuss the static beam loading, which includes the cavity detuning condition, the stability condition, and the generator power dissipation. The beam current induced beam phase deviation is used as criterion to study the transient beam loading. The upgraded and the old AGS RF system parameters are used as an example to demonstrate how to choose cavity and generator parameters to satisfy the stability requirements under the beam loading. The dynamic models for the beam loading with beam control, and the beam loading with fast power amplifier feedback are presented and analyzed. It is shown that the beam phase and radial feedbacks alone are insufficient for the transient beam loading compensation, but the fast power amplifier feedback can provide effective correction on the beam loading. The limitation of the fast feedback and the beam loading with tuning and AVC loops are also discussed.
Download or read book Transient Beam Loading in the SLC Damping Rings written by and published by . This book was released on 1995 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effects arising from heavy beam loading in the Stanford Linear Collider (SLC) Damping Rings are described. The stability of the rf system and particle beam is studied using a numerical model of the beam cavity interaction with multiple feedback loops. Nonlinearities of the power source are also considered. The effects of beam-induced transients and intensity jitter on the rf system are analyzed and used to determine stability tolerances for both high current and low current pulses.
Download or read book Measurement and Control of Charged Particle Beams written by Michiko G. Minty and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: From the reviews: "This book is a very welcome and valuable addition to the accelerator literature. As noted by the authors, there is relatively little material in the book specifically for low-energy machines, but industrial users may still find it useful to read." Cern Courier
Download or read book Beam Loading Effects in the APS Booster written by and published by . This book was released on 1996 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Beam loading of the radio-frequency (rf) accelerating cavities is an important consideration in the design and operation of high-current circular particle accelerators and storage rings. The steady-state and transient perturbations of the rf cavity system by the circulating beam can be harmful to the beam and limit the accelerator performance. Transient beam loading effects have been observed soon after injection of the beam into the booster synchrotron of the Advanced Photon Source (APS). Data are presented quantifying the responses of both the beam and the rf cavities to beam loading under various conditions. A preliminary discussion addresses the compensation of these beam loading effects. 3 refs., 3 figs., 1 tab.
Download or read book Operating Experience with High Beam Currents and Transient Beam Loading in the SLC Damping Rings written by and published by . This book was released on 1995 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the 1994 SLC run the nominal operating intensity in the damping rings was raised from 3.5 x 101° to greater than 4 x 101° particles per bunch (ppb). Stricter regulation of rf system parameters was required to maintain stability of the rf system and particle beam. Improvements were made in the feedback loops which control the cavity amplitude and loading angles. Compensation for beam loading was also required to prevent klystron saturation during repetition rate changes. To minimize the effects of transient loading on the rf system, the gain of the direct rf feedback loop and the loading angles were optimized.
Download or read book Transient Beam Loading Effects in Gas filled RF Cavities for a Muon Collider written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A gas-filled RF cavity can be an effective solution for the development of a compact muon ionization cooling channel. One possible problem expected in this type of cavity is the dissipation of significant RF power through the beam-induced plasmas accumulated inside the cavity (plasma loading). In addition, for the higher muon beam intensity, the effects of the beam itself on the cavity accelerating mode are non-negligible (beam loading). These beam- cavity interactions induce a transient phase which may be very harmful to the beam quality [1]. In this study, we estimate the transient voltage in a gas-filled RF cavity with both the plasma and conventional beam loading and discuss their compensation methods.
Download or read book Rf Beam Loading in the Brookhaven AGS with Booster Injection written by and published by . This book was released on 1992 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-batch bunched beam loading during injection from the Booster to the AGS will be discussed. The full intensity beam injection to the upgraded AGS rf system with beam phase and radial feedbacks will be studied. It is shown that a beam phase feedback is necessary in order to guarantee a predictable hewn behavior after the first batch injection, otherwise the initial phase deviation for the following batch injections cannot be controlled. However, the effectiveness of the phase feedback control of the transient beam loading may be limited by an emittance blow up in the process. It is shown that a fast power amplifier feedback with a moderate gain can significantly reduce the transient effect of the bunched beam injection.
Download or read book Analysis of Periodic Transient Beam Loading of the AGS written by and published by . This book was released on 1992 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this note, we discuss the multi-batch bunched ;beam loading during the injection from the Booster to the AGS. The full intensity beam injection to the upgraded AGS RF system with beam phase and radial feedbacks will be studied. It is shown that a beam phase feed-back is necessary in order to guarantee a predictable beam behavior after the first batch injection, otherwise the initial phase deviation for the following batch injections cannot be controlled. However, the effectiveness of the phase feedback control of the transient beam loading is limited by the associated emittance blow-up in the process. It is shown that a fast power amplifier feedback with a moderate gain can significantly reduce the transient effect of the bunched beam injection.
Download or read book Low level RF System Design for the Accelerator Test Facility ATF Damping Ring written by and published by . This book was released on 1997 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ATF damping ring was built to demonstrate the production of low emittance, high current beams for future linear colliders. To attain high beam currents, multiple high current bunch trains are required. The low-level rf system should be designed to minimize both steady-state and transient beam loading effects in the accelerating cavities. In addition the design should be sufficiently flexible to allow for a variety of beam dynamics tests which require a wide range of beam currents and cavity voltages. The low-level rf system and stability boundaries for reduced power and full power operation are discussed in this paper.
Download or read book Transient Beam Loading and Rf Power Distribution in the SSC Superconducting Super Collider written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Transient beam loading will occur in the SSC at injection as the fifteen individual batches from the High Energy Booster are loaded box-car fashion into the main rings. Periodic transient beam loading will be present also at injection due to the gaps between the successive batches as well as the gap that remains to be filled. Even after the rings have been ''filled'' there will remain the abort gap of 3.1 .mu.sec. This can produce significant modulation of the phase and amplitude of the rf voltage seen by those bunches immediately following it unless corrective measures are taken. Two different methods of reducing this modulation will be discussed, each of which put certain requirements on the rf power distribution system.
Download or read book Variable Current Transient Beam Loading Compensation written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: The energy spread caused by transients during beam turn-on can be reduced by suitable timing of the beam turn-on[1]. If the beam is injected when the no-load voltage reaches the desired loaded voltage, then the energy spread is about 10%. To eliminate this energy spread, one can amplitude or phase modulate the section input power for one fill time, so that when the beam is turned on, the no-load voltage equals the desired loaded voltage and from then on, the change in no-load voltage tracks the beam induced voltage. It is known that for a constant gradient (CG) structure, and amplitude variation of the form E(t) = a0 + (1 - a0) t{sub p} will reduce the energy spread to zero for a current that is determined by a0. When one uses rf modulation for transient beam loading compensation, the beam is injected a fill time after the rf has been turned on, and one is forced to throw away a section's worth of rf energy. In addition, it requires extra components which use up additional rf energy. This note describes transient beam loading compensation with variable current. It will show that it increases the rf energy to beam energy transfer efficiency.
Download or read book Transient Beam Loading Compensation in Traveling Wave Linear Accelerators written by and published by . This book was released on 1998 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transient Beam Loading Compensation in Traveling Wave Linear Accelerators written by Norbert Holtkamp and published by . This book was released on 1996 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Transient Beam Loading in Electron positron Storage Rings written by and published by . This book was released on 1978 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this note the fundamental of transient beam loading in electron-positron storage rings will be reviewed. The notation, and some of the material, has been introduced previously. The present note is, however, more tutorial in nature, and in addition the analysis is extended to include the transient behaviour of the cavity fields and reflected power between bunch passages. Since we are not bound here by the rigid space limitations of a paper for publication, an attempt is made to give a reasonably coherent and complete discussion of transient beam loading that can hopefully be followed even by the uninitiated. The discussion begins with a consideration of the beam-cavity interaction in the ''single-pass'' limit. In this limit it is assumed that the fields induced in the cavity by the passage of a bunch have decayed essentially to zero by the time the next bunch has arrived. The problem of the maximum energy that can be extracted from a cavity by a bunch is given particular attention, since this subject seems to be the source of some confusion. The analysis is then extended to the ''multiple-pass'' case, where the beam-induced fields do not decay to zero between bunches, and to a detailed consideration of the transient variation of cavity fields and reflected power. The note concludes with a brief discussion of the effect of transient beam loading on quantum lifetime.
