Download or read book The Next Linear Collider Test Accelerator s RF Pulse Compression and Transmission Systems written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The overmoded rf transmission and pulsed power compression system for SLAC's Next Linear Collider (NLC) program requires a high degree of transmission efficiency and mode purity to be economically feasible. To this end, a number of new, high power components and systems have been developed at X-band, which transmit rf power in the low loss, circular TE01 mode with negligible mode conversion. In addition, a highly efficient SLED-II* pulse compressor has been developed and successfully tested at high power. The system produced a 200 MW, 250 ns wide pulse with a near-perfect flat-top. In this paper we describe the design and test results of the high power pulse compression system using SLED-II.

Download or read book The Next Linear Collider Test Accelerator s RF Pulse Compression And Transmission written by and published by . This book was released on 2011 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: The overmoded rf transmission and pulsed power compression system for SLAC's Next Linear Collider (NLC) program requires a high degree of transmission efficiency and mode purity to be economically feasible. To this end, a number of new, high power components and systems have been developed at X-band, which transmit rf power in the low loss, circular TE01 mode with negligible mode conversion. In addition, a highly efficient SLED-II* pulse compressor has been developed and successfully tested at high power. The system produced a 200 MW, 250 ns wide pulse with a near-perfect flat-top. In this paper we describe the design and test results of the high power pulse compression system using SLED-II. The NLC rf systems use low loss highly over-moded circular waveguides operating in the TE01 mode. The efficiency of the systems is sensitive to the mode purity of the mode excited inside these guides. We used the so called flower petal mode transducer [2] to excite the TE01 mode. This type of mode transducer is efficient, compact and capable of handling high levels of power. To make more efficient systems, we modified this device by adding several mode selective chokes to act as mode purifiers. To manipulate the rf signals we used these modified mode converters to convert back and forth between over-moded circular waveguides and single-moded WR90 rectangular waveguides. Then, we used the relatively simple rectangular waveguide components to do the actual manipulation of rf signals. For example, two mode transducers and a mitered rectangular waveguide bend comprise a 90 degree bend. Also, a magic tee and four mode transducers would comprise a four-port-hybrid, etc. We will discuss the efficiency of an rf transport system based on the above methodology. We also used this methodology in building the SLEDII pulse compression system. At SLAC we built 4 of these pulse systems. In this paper we describe the SLEDII system and compare the performance of these 4 systems at SLAC. We report the experimental procedures used to measure their performance as well as the results of high power tests.

Download or read book A Test Accelerator for the Next Linear Collider written by and published by . This book was released on 1993 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: At SLAC, the authors are pursuing the design of a Next Linear Collider (NLC) which would begin with a center-of-mass energy of 0.5 TeV, and be upgradable to at least 1.0 TeV. To achieve this high energy, they have been working on the development of a high-gradient 11.4-GHz (X-band) linear accelerator for the main linac of the collider. In this paper, they present the design of a {open_quotes}Next Linear Collider Test Accelerator{close_quotes} (NLCTA). The goal of the NLCTA is to incorporate the new technologies of X-band accelerator structures, RF pulse compression systems and klystrons into a short linac which will then be a test bed for beam dynamics issues related to high-gradient acceleration.

Download or read book The Next Linear Collider Test Accelerator written by and published by . This book was released on 1992 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past several years, there has been tremendous progress on the development of the RF system and accelerating structures for a Next Linear Collider (NLC). Developments include high-power klystrons, RF pulse-compression systems and damped/detuned accelerator structures to reduce wakefields. In order to integrate these separate development efforts into an actual X-band accelerator capable of accelerating the electron beams necessary for an NLC, we plan to build an NLC Test Accelerator (NLCTA). The goal of the NLCTA is to bring together all elements of the entire accelerating system by constructing. and reliably operating an engineered model of a high-gradient linac suitable for the NLC. The NLCTA win serve as a test-bed as the design of the NLC evolves and will provide a model upon which a reliable cost estimate can be based. In addition to testing the RF acceleration system, the NLCTA will be able to address many questions related to the dynamics of the beam during acceleration. In this paper, we will report on the status of the design and component development for the NLC Test Accelerator.

Download or read book Geistliche Lieder vnd Psalmen M D L III written by and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book RF Pulse Compression in the NLC Test Accelerator at SLAC written by and published by . This book was released on 1995 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: At the Stanford Linear Accelerator Center (SLAC), the authors are designing a Next Linear Collider (NLC) with linacs powered by X-band klystrons with rf pulse compression. The design of the linac rf system is based on X-band prototypes which have been tested at high power, and on a systems-integration test - the Next Linear Collider Test Accelerator (NLCTA) - which is currently under construction at SLAC. This paper discusses some of the systems implications of rf pulse compression, and the use of pulse compression in the NLCTA, both for peak power multiplication and for controlling, by rf phase modulation, intra-pulse variations in the linac beam energy.

Download or read book Status and Results from the Next Linear Collider Test Accelerator written by and published by . This book was released on 1996 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The design for the Next Linear Collider (NLC) at SLAC is based on two 11.4 GHz linacs operating at an unloaded acceleration gradient of 50 MV/m increasing to 85 MV/m as the energy is increased from 1/2 TeV to 1 TeV in the center of mass. During the past several years there has been tremendous progress on the development of 11.4 GHz (X-band) RF systems. These developments include klystrons which operate at the required power and pulse length, pulse compression systems that achieve a factor of four power multiplication and structures that are specially designed to reduce long-range wakefields. Together with these developments, we have constructed a 1/2 GeV test accelerator, the NLC Test Accelerator (NLCTA). The NLCTA will serve as a test bed as the design of the NLC is refined. In addition to testing the RF system, the NLCTA is designed to address many questions related to the dynamics of the beam during acceleration, in particular the study of multibunch beam loading compensation and transverse beam break-up. In this paper we present the status of the NLCTA and the results of initial commissioning.

Download or read book RF Pulse Compression for Future Linear Colliders written by and published by . This book was released on 1995 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Future (nonsuperconducting) linear colliders will require very high values of peak rf power per meter of accelerating structure. The role of rf pulse compression in producing this power is examined within the context of overall rf system design for three future colliders at energies of 1.0--1.5 TeV, 5 TeV and 25 TeV. In order keep the average AC input power and the length of the accelerator within reasonable limits, a collider in the 1.0--1.5 TeV energy range will probably be built at an x-band rf frequency, and will require a peak power on the order of 150--200 MW per meter of accelerating structure. A 5 TeV collider at 34 GHz with a reasonable length (35 km) and AC input power (225 MW) would require about 550 MW per meter of structure. Two-beam accelerators can achieve peak powers of this order by applying dc pulse compression techniques (induction linac modules) to produce the drive beam. Klystron-driven colliders achieve high peak power by a combination of dc pulse compression (modulators) and rf pulse compression, with about the same overall rf system efficiency (30--40%) as a two-beam collider. A high gain (6.8) three-stage binary pulse compression system with high efficiency (80%) is described, which (compared to a SLED-11 system) can be used to reduce the klystron peak power by about a factor of two, or alternately, to cut the number of klystrons in half for a 1.0--1.5 TeV x-band collider. For a 5 TeV klystron-driven collider, a high gain, high efficiency rf pulse compression system is essential.

Download or read book Loaded Delay Lines for Future RF Pulse Compression Systems written by and published by . This book was released on 1995 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The peak power delivered by the klystrons in the NLCRA (Next Linear Collider Test Accelerator) now under construction at SLAC is enhanced by a factor of four in a SLED-II type of R.F. pulse compression system (pulse width compression ratio of six). To achieve the desired output pulse duration of 250 ns, a delay line constructed from a 36 m length of circular waveguide is used. Future colliders, however, will require even higher peak power and larger compression factors, which favors a more efficient binary pulse compression approach. Binary pulse compression, however, requires a line whose delay time is approximately proportional to the compression factor. To reduce the length of these lines to manageable proportions, periodically loaded delay lines are being analyzed using a generalized scattering matrix approach. One issue under study is the possibility of propagating two TE{sub o} modes, one with a high group velocity and one with a group velocity of the order 0.05c, for use in a single-line binary pulse compression system. Particular attention is paid to time domain pulse degradation and to Ohmic losses.

Download or read book High Power Multimode X Band RF Pulse Compression System for Future Linear Colliders written by and published by . This book was released on 2005 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a multimode X-band rf pulse compression system suitable for a TeV-scale electron-positron linear collider such as the Next Linear Collider (NLC). The NLC main linac operating frequency is 11.424 GHz. A single NLC rf unit is required to produce 400 ns pulses with 475 MW of peak power. Each rf unit should power approximately 5 m of accelerator structures. The rf unit design consists of two 75 MW klystrons and a dual-moded resonant-delay-line pulse compression system that produces a flat output pulse. The pulse compression system components are all overmoded, and most components are designed to operate with two modes. This approach allows high-power-handling capability while maintaining a compact, inexpensive system. We detail the design of this system and present experimental cold test results. We describe the design and performance of various components. The high-power testing of the system is verified using four 50 MW solenoid-focused klystrons run off a common 400 kV solid-state modulator. The system has produced 400 ns rf pulses of greater than 500 MW. We present the layout of our system, which includes a dual-moded transmission waveguide system and a dual-moded resonant line (SLED-II) pulse compression system. We also present data on the processing and operation of this system, which has set high-power records in coherent and phase controlled pulsed rf.

Download or read book High power Rf Pulse Compression with SLED II at SLAC written by and published by . This book was released on 1993 with total page 3 pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasing the peak rf power available from X-band microwave tubes by means of rf pulse compression is envisioned as a way of achieving the few-hundred-megawatt power levels needed to drive a next-generation linear collider with 50--100 MW klystrons. SLED-II is a method of pulse compression similar in principal to the SLED method currently in use on the SLC and the LEP injector linac. It utilizes low-los resonant delay lines in place of the storage cavities of the latter. This produces the added benefit of a flat-topped output pulse. At SLAC, we have designed and constructed a prototype SLED-II pulse-compression system which operates in the circular TE01 mode. It includes a circular-guide 3-dB coupler and other novel components. Low-power and initial high-power tests have been made, yielding a peak power multiplication of 4.8 at an efficiency of 40%. The system will be used in providing power for structure tests in the ASTA (Accelerator Structures Test Area) bunker. An upgraded second prototype will have improved efficiency and will serve as a model for the pulse compression system of the NLCTA (Next Linear Collider Test Accelerator).

Download or read book RF Pulse Compression and Alternative RF Sources for Linear Colliders written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Future linear colliders will require a very high peak power per meter of accelerating structure at a relatively high frequency-greater than 10 GHz-but at a relatively short pulse length-less than 100 ns. One technique for generating the required peak power is to use a more or less conventional microwave power source, which produces power at a pulse length typically on the order of 1 s, together with RF pulse compression. Some parameters are given for a Binary Power Multiplier (BPM) pulse compression system operating at 17.1 GHz with an output pulse length of 60 ns. The peak power gain for a three stage system is estimated to be 6.6 (82% compression efficiency). Some possible long-pulse microwave sources which-when coupled with such a pulse compression system-would be suitable for driving a linear collider are briefly discussed. 13 refs., 1 fig., 1 tab.

Download or read book Epac 96 written by S. Myers and published by CRC Press. This book was released on 1996-01-01 with total page 1054 pages. Available in PDF, EPUB and Kindle. Book excerpt: EPAC 96; Proceedings of the Fifth European Particle Accelerator Conference, Sitges (Barcelona), 10 to 14 June 1996, Three Volume Set, also available on a CD-ROM, provides a comprehensive overview of research, technology, and special applications in the field of accelerators. It serves as a source for novel ideas and familiarizes researchers with advanced concepts.

Download or read book Radio Frequency Pulse Compression Experiments at SLAC Stanford Linear Accelerator Center written by and published by . This book was released on 1991 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proposed future positron-electron linear colliders would be capable of investigating fundamental processes of interest in the 0.5--5 TeV beam-energy range. At the SLAC Linear Collider (SLC) gradient of about 20 MV/m this would imply prohibitive lengths of about 50--250 kilometers per linac. We can reduce the length by increasing the gradient but this implies high peak power, on the order of 400-- to 1000-MW at X-Band. One possible way to generate high peak power is to generate a relatively long pulse at a relatively low power and compress it into a short pulse with higher peak power. It is possible to compress before DC to RF conversion, as is done using magnetic switching for induction linacs, or after DC to RF conversion, as is done for the SLC. Using RF pulse compression it is possible to boost the 50-- to 100-MW output that has already been obtained from high-power X-Band klystrons the levels required by the linear colliders. In this note only radio frequency pulse compression (RFPC) is considered.

Download or read book New Development in RF Pulse Compression written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Several pulse compression systems have been proposed for future linear collider. Most of these systems require hundreds of kilometers of low-loss waveguide runs. To reduce the waveguide length and improve the efficiency of these systems, components for multimoding, active switches and non-reciprocal elements are being developed. In the multimoded systems a waveguide is utilized several times by sending different signals over different modes. The multimoded components needed for these systems have to be able to handle hundreds of megawatts of rf power at the X-band frequency and above. Consequently, most of these components are overmoded. The authors present the development of multimoded components required for such systems. They also present the development efforts towards overmoded active component such as switches and overmoded non-reciprocal components such as circulators and isolators.

Download or read book Experimental Demonstration of an RF System for the X Band Linear Collider written by and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Designs for a future X-band linear collider (NLC/GLC) require an rf unit that can produce 450 MW to feed eight 60 cm accelerator structures. The implementation of this rf unit is envisioned to include a dual-moded SLED-II pulse compression system, with a gain of approximately three at a compression ratio of four, followed by an overmoded transmission and distribution system. We describe the tunnel layout plan for these rf systems. The design, construction, and operation of a prototype system are a focus of the 8-Pack project at SLAC. In its initial phase last fall, powered by four 50 MW X-band klystrons sharing a common 400 kV solid-state modulator, the SLED-II system delivered to a set of loads 400 ns pulses of up to 580 MW. In the next phase, this power will be delivered to the NLCTA beamline and distributed between several structures, through which a bunch train will be accelerated. We describe the layout of this system and the functionality of various overmoded, high-power components which comprise it. We also present data on the cold testing, processing and initial operation of the system, which is setting high-power records in pulsed rf.

Download or read book International Linear Collider Technical Review Committee Second Report 2003 written by International Linear Collider Technical Review Committee and published by . This book was released on 2003 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: