Download or read book Low level RF System Design for the Next Linear Collider 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 design current for the Next Linear Collider (NLC) damping rings is an order of magnitude higher than existing damping rings. As opposed to storage rings, damping rings are required to operate at a high repetition frequency. Transient beam loading is therefore particularly severe. The NLC design calls for a full current fill pattern consisting of up to 4 trains of 90 bunches for a total dc current of 1.2 A. However, using conventional filling techniques, with a rapid current ramp the ring energy acceptance could decrease due to transient loading and the beam might not be captured. In this paper the authors describe two features of the low-level rf system design. The first avoids any reduction of duty cycle while the second ensures beam capture and regulation of the cavity voltages and beam phase.

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 The Next Linear Collider Damping Ring Complex written by and published by . This book was released on 1999 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Damping Ring Design for the SLAC Next Linear Collider written by and published by . This book was released on 1995 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Damping Ring Rf System for SLC written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The linear collider project at SLAC contains two damping rings to reduce the emittance of short electron or positron bunches which contain 5 x 101° particles per bunch. Two of these bunches are stored at a time and then extracted for acceleration in the collider. The rf system is subject to strong transients in beam loading. A computer model is used to optimize capture while minimizing rf power. The introduction of phase jump in the rf drive at injection time together with offsets in the tuning loops of the rf cavities when no beam is stored allows optimum performance under heavy beam load conditions. The rf system (800 kV at 714 MHz) for the electron damping ring has been built, tested and installed, and is being tested with beam.

Download or read book Tavole written by and published by . This book was released on 1997 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vol. 2 Tomo 1-3

Download or read book The Next Linear Collider Damping Ring Lattices written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We report on the lattice design of the Next Linear Collider (NLC) damping rings. The damping rings are required to provide low emittance electron and positron bunch trains to the NLC linacs, at a rate of 120 Hz. We present an optical design, based on a theoretical minimum emittance (TME) lattice, to produce the required normalized extracted beam emittances gex = 3 mm-mrad and gey = 0.02 mm mrad. An assessment of dynamic aperture and non-linear effects is given. The positron pre-damping ring, required to reduce the emittance of the positron beam such that it may be accepted by a main damping ring, is also described.

Download or read book Low level RF Signal Processing for the Next Linear Collider Test Accelerator written by and published by . This book was released on 1997 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the X-band accelerator system for the Next Linear Collider Test Accelerator (NLCTA), the Low Level RF (LLRF) drive system must be very phase stable, but concurrently, be very phase agile. Phase agility is needed to make the Stanford Linear Doubler (SLED) power multiplier systems Energy work and to shape the RF waveforms to compensate beam loading in the accelerator sections. Similarly, precision fast phase and amplitude monitors are required to view, track, and feed back on RF signals at various locations throughout the system. The LLRF is composed of several subsystems: the RF Reference System generates and distributes a reference 11.424 GHz signal to all of the RF stations, the Signal Processing Chassis creates the RF waveforms with the appropriate phase modulation, and the Phase Detector Assembly measures the amplitude and phase of monitor3ed RF signals. The LLRF is run via VXI instrumentation. These instruments are controlled using HP VEE graphical programming software. Programs have been developed to shape the RF waveform, calibrate the phase modulators and demodulators, and display the measured waveforms. This paper describes these and other components of the LLRF system.

Download or read book A Damping Ring Design for Future Linear Colliders written by and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this paper we present a preliminary design of a damping ring for the TeV Linear Collider (TLC), a future linear collider with an energy of 1/2 to 1 TeV in the center of mass. Because of limits on the emittance, repetition rate and longitudinal impedance, we use combined function FODO cells with wigglers in insertion regions; there are approximately 22 meters of wigglers in the 155 meter ring. The ring has a normalized horizontal emittance, including the effect of intrabeam scattering, which is less than 3 /times/ 10/sup -6/ and an emittance ratio of epsilon/sub x/ approx. 100epsilon/sub y/. It is designed to damp bunches for 7 vertical damping times while operating at a repetition rate of 360 Hz. Because of these requirements on the emittance and the damping per bunch, the ring operates at 1.8 GeV and is relatively large, allowing more bunches to be damped at once. 10 refs., 5 figs., 2 tabs.

Download or read book Feedback Systems for Linear Colliders written by and published by . This book was released on 1999 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Feedback systems are essential for stable operation of a linear collider, providing a cost-effective method for relaxing tight tolerances. In the Stanford Linear Collider (SLC), feedback controls beam parameters such as trajectory, energy, and intensity throughout the accelerator. A novel dithering optimization system which adjusts final focus parameters to maximize luminosity contributed to achieving record performance in the 1997-98 run. Performance limitations of the steering feedback have been investigated, and improvements have been made. For the Next Linear Collider (NLC), extensive feedback systems are planned as an integral part of the design. Feedback requirements for JLC (the Japanese Linear Collider) are essentially identical to NLC; some of the TESLA requirements are similar but there are significant differences. For NLC, algorithms which incorporate improvements upon the SLC implementation are being prototyped. Specialized systems for the damping rings, rf and interaction point will operate at high bandwidth and fast response. To correct for the motion of individual bunches within a train, both feedforward and feedback systems are planned. SLC experience has shown that feedback systems are an invaluable operational tool for decoupling systems, allowing precision tuning, and providing pulse-to-pulse diagnostics. Feedback systems for the NLC will incorporate the key SLC features and the benefits of advancing technologies.

Download or read book Optics Design and Performance of an Ultra low Emittance Damping Ring for the Compact Linear Collider written by Maxim Korostelev and published by . This book was released on 2006 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Damping Ring R D at CESR TA written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Accelerators that collide high energy beams of matter and anti-matter are essential tools for the investigation of the fundamental constituents of matter, and the search for new forms of matter and energy. A "Linear Collider" is a machine that would bring high energy and very compact bunches of electrons and positrons (anti-electrons) into head-on collision. Such a machine would produce (among many other things) the newly discovered Higgs particle, enabling a detailed study of its properties. Among the most critical and challenging components of a linear collider are the damping rings that produce the very compact and intense beams of electrons and positrons that are to be accelerated into collision. Hot dilute particle beams are injected into the damping rings, where they are compressed and cooled. The size of the positron beam must be reduced more than a thousand fold in the damping ring, and this compression must be accomplished in a fraction of a second. The cold compact beams are then extracted from the damping ring and accelerated into collision at high energy. The proposed International Linear Collider (ILC), would require damping rings that routinely produce such cold, compact and intense beams. The goal of the Cornell study was a credible design for the damping rings for the ILC. Among the technical challenges of the damping rings; the development of instrumentation that can measure the properties of the very small beams in a very narrow window of time, and mitigation of the forces that can destabilize the beams and prevent adequate cooling, or worse lead to beam loss. One of the most pernicious destabilizing forces is due to the formation of clouds of electrons in the beam pipe. The electron cloud effect is a phenomenon in particle accelerators in which a high density of low energy electrons, build up inside the vacuum chamber. At the outset of the study, it was anticipated that electron cloud effects would limit the intensity of the positron ring, and that an instability associated with residual gas in the beam pipe would limit the intensity of the electron ring. It was also not clear whether the required very small beam size could be achieved. The results of this study are important contributions to the design of both the electron and positron damping rings in which all of those challenges are addressed and overcome. Our findings are documented in the ILC Technical Design Report, a document that represents the work of an international collaboration of scientists. Our contributions include design of the beam magnetic optics for the 3 km circumference damping rings, the vacuum system and surface treatments for electron cloud mitigation, the design of the guide field magnets, design of the superconducting damping wigglers, and new detectors for precision measurement of beam properties. Our study informed the specification of the basic design parameters for the damping rings, including alignment tolerances, magnetic field errors, and instrumentation. We developed electron cloud modelling tools and simulations to aid in the interpretation of the measurements that we carried out in the Cornell Electron-positron Storage Ring (CESR). The simulations provide a means for systematic extrapolation of our measurements at CESR to the proposed ILC damping rings, and ultimately to specify how the beam pipes should be fabricated in order to minimize the effects of the electron cloud. With the conclusion of this study, the design of the essential components of the damping rings is complete, including the development and characterization (with computer simulations) of the beam optics, specification of techniques for minimizing beam size, design of damping ring instrumentation, R & D into electron cloud suppression methods, tests of long term durability of electron cloud coatings, and design of damping ring vacuum system components.

Download or read book Radio Frequency Station beam Dynamics Interaction in Circular Accelerators written by Themistoklis Mastoridis and published by Stanford University. This book was released on 2005 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: The longitudinal beam dynamics in circular accelerators is mainly defined by the interaction of the beam current with the accelerating Radio Frequency (RF) stations. For stable operation, Low Level RF (LLRF) feedback systems are employed to reduce coherent instabilities and regulate the accelerating voltage. The LLRF system design has implications for the dynamics and stability of the closed-loop RF systems as well as for the particle beam, and is very sensitive to the operating range of accelerator currents and energies. Stability of the RF loop and the beam are necessary conditions for reliable machine operation. This dissertation describes theoretical formalisms and models that determine the longitudinal beam dynamics based on the LLRF implementation, time domain simulations that capture the dynamic behavior of the RF station-beam interaction, and measurements from the Positron-Electron Project (PEP-II) and the Large Hadron Collider (LHC) that validate the models and simulations. These models and simulations are structured to capture the technical characteristics of the system (noise contributions, non-linear elements, and more). As such, they provide useful results and insight for the development and design of future LLRF feedback systems. They also provide the opportunity to study diverse longitudinal beam dynamics effects such as coupled-bunch impedance driven instabilities and single bunch longitudinal emittance growth. Coupled-bunch instabilities and RF station power were the performance limiting effects for PEP-II. The sensitivity of the instabilities to individual LLRF parameters, the effectiveness of alternative operational algorithms, and the possible tradeoffs between RF loop and beam stability were studied. New algorithms were implemented, with significant performance improvement leading to a world record current during the last PEP-II run of 3212 mA for the Low Energy Ring. Longitudinal beam emittance growth due to RF noise is a major concern for LHC. Simulations studies and measurements were conducted that clearly show the correlation between RF noise and longitudinal bunch emittance, identify the major LLRF noise contributions, and determine the RF component dominating this effect. With these results, LHC upgrades and alternative algorithms are evaluated to reduce longitudinal emittance growth during operations. The applications of this work are described with regard to future machines and analysis of new technical implementations, as well as to possible future work which would continue the directions of this dissertation.

Download or read book 1 2 GeV Damping ring Complex for the Stanford Linear Collider written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The choice of parameters, the design, a 2-1/2 year consruction program and the early operation of a high field, high tune research and development damping ring complex for one of the two linear collider beams are described.

Download or read book written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design of an RF System for the ATF Damping Ring written by S. Sakanaka and published by . This book was released on 1995 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the 1999 Particle Accelerator Conference written by and published by . This book was released on 1999 with total page 862 pages. Available in PDF, EPUB and Kindle. Book excerpt: