{"title":"Filament power supply improvement of the TRIUMF RF system","authors":"A. Mitra, J.J. Lu","doi":"10.1109/PAC.1993.308614","DOIUrl":"https://doi.org/10.1109/PAC.1993.308614","url":null,"abstract":"The TRIUMF RF system, operating at a fixed frequency of 23.06 MHz, employs four push-pull power amplifiers using eight EIMAC 4CW250,000 tetrodes. The filament power supplies for the above tetrodes uses simplified three phase SCR control circuits to slowly ramp up the output voltage. Failure of SCR's during ramping and also during power bumps has been a source of RF downtime. A new SCR control scheme has been developed and tested which relies on the fact that the secondary output voltage from a three phase transformer will be 57.7% of it's rated output voltage if only two phases of the primary are connected. In this scheme, one phase is connected directly and the second phase is connected through two SCR's of which the conduction angle is controlled by a slow ramp. The third phase is initially blocked by two SCR's which are turned on fully after a fixed delay thereby limiting the surge current of the filament during start up. A greatly simplified firing circuit and smaller number of components has improved the reliability and the performance of such a power supply. Also, an alternate scheme of a power supply with series resistors in the primary of the transformer is described.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128711775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Wiggler as spin rotators for RHIC","authors":"A. Luccio, M. Conte","doi":"10.1109/PAC.1993.308889","DOIUrl":"https://doi.org/10.1109/PAC.1993.308889","url":null,"abstract":"The spin of a polarized particle in a circular accelerator can be rotated with an arrangement of dipoles with field mutually perpendicular and perpendicular to the orbit. To achieve spin rotation, a given field integral value is required. The device must be designed in a way that the particle orbit is distorted as little as possible. It is shown that wigglers with many periods are suitable to achieve spin rotation with minimum orbit distortions. Wigglers are also more compact than more established structures and will use less electric power. Additional advantages include their use for nondestructive beam diagnostics. Results are given for the Relativistic Heavy Ion Collider (RHIC) in the polarized proton mode.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128988022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Three dimensional field analysis for the AGS combined function magnets","authors":"W. Meng, M. Tanaka","doi":"10.1109/PAC.1993.309501","DOIUrl":"https://doi.org/10.1109/PAC.1993.309501","url":null,"abstract":"In order to study the particle trajectories in the fringe field of the AGS ring during the single bunch multiple extraction (or fast extraction) from the the AGS to the muon g-2 experiment and to the RHIC, the magnetic field of the AGS combined function magnets were calculated by using the TOSCA program. The results are compared with the field maps of the previous measurements. The particle tracking is achieved by using the TOSCA program postprocessor.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129358865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The high level RF system for transition crossing without RF focusing in the main ring at Fermilab","authors":"J. Dey, C. Bhat, A. Crawford, D. Wildman","doi":"10.1109/PAC.1993.308640","DOIUrl":"https://doi.org/10.1109/PAC.1993.308640","url":null,"abstract":"A new method for crossing transition at the Fermilab Main Ring has been developed. Near transition a third harmonic component is added to the fundamental RF voltage producing a flattened RF waveform. To generate this waveform required the development of a third harmonic system consisting of a 159 MHz cavity, a perpendicularly biased tuner,and a 10 kW power amplifier. The cavity is a modified CERN SPS 200 MHz cavity whose frequency was lowered to 159 MHz by inserting two sleeves at the cavity gap. This cavity is electrically tuned over a 60 kHz range by using an orthogonally biased Iron-Yttrium-Garnet ferrite tuner. The power amplifier is a grid driven tetrode that has a 3/4 /spl lambda/ anode resonator and produces a RF cavity gap voltage of greater than 300 kV. The power amplifier drives the cavity by way of a coupling loop. An overview of this high level RF system and the resulting waveform is given.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124602764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Design and performance of the inter-RFQ beam transport and matching section for the SAIC PET isotope production accelerator","authors":"W. Cornelius","doi":"10.1109/PAC.1993.309528","DOIUrl":"https://doi.org/10.1109/PAC.1993.309528","url":null,"abstract":"The SAIC PET isotope production accelerator is comprised of a 1 MeV /sup 3/He/sup +/ radio-frequency quadrupole (RFQ) accelerator followed by a charge-doubler and pair of RFQ accelerators to produce 8 MeV /sup 3/He/sup ++/ ions. The inter-RFQ section consists of a stripper and a transport system in order to match the beam into the following RFQ. This inter-RFQ section is functionally equivalent to a single-sided beam funnel where the bend magnet has been replaced with a stripper cell. The operating frequency is doubled from 212.5 MHz to 425 MHz and the beam must be matched transversely and longitudinally to the 425 MHz RFQ acceptance. The transverse matching is accomplished using permanent magnet quadrupoles and the longitudinal matching is accomplished using a buncher cavity. Our particular design is unique in that the transverse x:y diameter ratio can be as high as 4:1. Initially this asymmetry was thought to complicate the transport, however the system can be designed to exploit the unique features of a large aspect ratio and has important implications at other facilities.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124653889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I. Yampolsky, G. Kirkman, N. Reinhardt, J. Hur, B. Jiang
{"title":"Novel gigawatt power modulator for RF sources","authors":"I. Yampolsky, G. Kirkman, N. Reinhardt, J. Hur, B. Jiang","doi":"10.1109/PAC.1993.308606","DOIUrl":"https://doi.org/10.1109/PAC.1993.308606","url":null,"abstract":"A novel method for producing high voltage rectangular pulses for driving RF sources is described. The approach uses two advances in pulsed power technology: 1) The BLT switch and 2) Novel transmission line transformer techniques using switches between lines. Experimentally demonstrated is a modulator producing 80 kV, 800 A output pulse requiring only 22 kV switch voltage. The output pulse is /spl sim/120 nsec long with <40 nsec rise and fall times. A modulator designed to produce 1 MV, 1 kA output pulse using 50 kV switches is described and simulated by computer. The application of this modulator to drive RF sources for advanced accelerators is discussed.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124782864","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Measurement of trapped ion pockets and control of ion instabilities in the Fermilab antiproton accumulator","authors":"S. Werkema, K.D. Fullett, P. Zhou","doi":"10.1109/PAC.1993.309635","DOIUrl":"https://doi.org/10.1109/PAC.1993.309635","url":null,"abstract":"Resonant interaction of positively charged, trapped residual gas ions with a negatively charged, intense antiproton beam has been identified as the primary cause of transverse instability in the Fermilab antiproton accumulator. An upgraded ion clearing system was recently installed. This upgrade yielded a significant improvement in machine performance as well as an enhanced capability for studying trapped ion related phenomena. The operational impact and preliminary results from some initial measurements made with this system are presented herein.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"91 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129580580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
L. K. Mestha, V. Brouk, R. Webber, J. Mangino, T. Uher
{"title":"A digital beam phase loop for the Low Energy Booster","authors":"L. K. Mestha, V. Brouk, R. Webber, J. Mangino, T. Uher","doi":"10.1109/PAC.1993.309329","DOIUrl":"https://doi.org/10.1109/PAC.1993.309329","url":null,"abstract":"The Direct Digital Synthesizers (DDS) have a proven record of high frequency stability in accelerator beam control. For the Low Energy Booster working in the frequency range of 47 MHz to 60 MHz, a highly stable, high resolution DDS can improve the longitudinal beam stabilities. With the DDS as the source it would be highly desirable to make the beam phase loop digital. In this paper we show the description of the loop hardware and a method to simulate the performance in the presence of loop delay using a control system simulation software called SIMULINK. Some experimental hardware based on DDS system which was used to accelerate the beam in the FNAL booster is discussed.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129655772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Fontana, W. Kimura, L. Steinhauer, I. Pogorelsky
{"title":"Design analysis for a 100-MeV inverse Cerenkov laser accelerator","authors":"J. Fontana, W. Kimura, L. Steinhauer, I. Pogorelsky","doi":"10.1109/PAC.1993.309404","DOIUrl":"https://doi.org/10.1109/PAC.1993.309404","url":null,"abstract":"The analysis of a 100-MeV demonstration experiment based upon inverse Cerenkov acceleration (ICA) is presented. This experiment would use the Accelerator Test Facility (ATF) at Brookhaven National Laboratory. With 50-GW of delivered laser peak power from the ATF CO/sub 2/ laser, our analysis indicates the 65-MeV ATF e-beam can be accelerated to >165 MeV using three stages of acceleration in /spl sim/1 m of total length. The number of electrons accelerated can be raised to /spl sim/10/sup 9/ by prebunching the e-beam using an already available device.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"267 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129899687","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
G. Ingold, L. Solomon, I. Ben-Zvi, S. Krinsky, D. Li, D. Lynch, J. Sheehan, N. Woodle, X. Qiu, L. Yu, X. Zhang, W. Sampson, M. Gardner, K. Robins, I. Lehrman, R. Heuer, J. Sheehan, D. Weissenburger
{"title":"A superconducting short period undulator for a harmonic generation FEL experiment","authors":"G. Ingold, L. Solomon, I. Ben-Zvi, S. Krinsky, D. Li, D. Lynch, J. Sheehan, N. Woodle, X. Qiu, L. Yu, X. Zhang, W. Sampson, M. Gardner, K. Robins, I. Lehrman, R. Heuer, J. Sheehan, D. Weissenburger","doi":"10.1109/PAC.1993.308577","DOIUrl":"https://doi.org/10.1109/PAC.1993.308577","url":null,"abstract":"A three stage superconducting (SC) undulator for a high gain harmonic generation (HGE) FEL experiment in the infrared is under construction at the NSLS in collaboration with Grumman Corporation. A novel undulator technology suitable for short period (6-40 mm) undulators will be employed for all three stages, the modulator, the dispersive section and the radiator. The undulator triples the frequency of a 10.4 /spl mu/m CO/sub 2/ seed laser. So far a 27 period (one third of the final radiator) prototype radiator has been designed, built and tested.<<ETX>>","PeriodicalId":128308,"journal":{"name":"Proceedings of International Conference on Particle Accelerators","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1993-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130307603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}