| Paper | Title | Page |
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| MPPP036 | Collective Effects for NSLS-II | |
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| NSLS-II is a 3 GeV ultra high brightness storage ring that is planned to succeed the present NSLS rings at Brookhaven. NSLS-II will provide hard X-ray photons from ~20 mini-gap undulators that may significantly contribute to the machine impedance. This, in combination with very high beam phase space density, and low momentum compaction drives a number of coherent instabilities. This paper reviews the most important collective effects for NSLS-II and their implications on the machine design. | ||
| MPPP038 | Harmonic Cavity Performance for NSLS-II | 2544 |
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| NSLS-II is a 3 GeV ultra-high brightness storage ring that is planned to succeed the present NSLS rings at Brookhaven. Ultra-low emittance bunch combined with a short bunch length results in the Touschek lifetime of only a few hours, which strongly advocates including harmonic RF in the baseline design of NSLS-II. This paper describes the required harmonic RF parameters, trade-offs between the possible choices and the expected system performance, including the implications on lifetime and instabilities. | ||
| MPPP039 | Impedance of Finite Length Resistor | 2595 |
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Funding: Department of Energy contract DE-AC02-98CH10886. We determine the impedance of a cylindrical metal tube (resistor) of radius a and length g, attached at each end to perfect conductors of semi-infinite length. Our main interest is in the behavior of the impedance at high frequency (k>>1/a). In the equilibrium regime, ka2<<g, the impedance per unit length is accurately described by the well-known result for an infinite length resistive tube. In the transient regime, ka2>>g, we derive an analytic expression for the impedance and compute the short-range wakefield. |
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| TPAT017 | Transverse Impedance of Elliptical Tapers | 1535 |
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Funding: Work supported by the U.S. DOE. The geometric impedance of small-gap undulator chambers is of paramount importance for modern light sources because it may drive transverse single bunch instabilities. Analytical expressions are derived for the transverse impedance assuming a slowly tapered vacuum chamber with a confocal elliptical cross-section. The analytical results are confirmed by numerical simulations with the GdfidL Electromagnetic Field simulator and they yield the correct asymptotic limits for both round and flat chambers. |
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| TOAB008 | New Storage Ring Light Sources on the Horizon | |
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Funding: Work supported by the U.S. DOE. The world’s appetite for light sources keeps growing as new ones are under construction or being proposed for every continent but Antarctica. While some viable alternatives are emerging, the great majority of new light sources are based on mature electron storage ring technology. We review the design and performance of the new machines worldwide and speculate on the future directions. |
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| RPAE058 | NSLS-II Injection Concept | 3408 |
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| Currently the facility upgrade project is under progress at the NSLS (Brookhaven National Laboratory). The goal of NSLS-II is a 3 GeV ultra-low emittance storage ring that will provide three orders of magnitude increase in brightness over the present NSLS X-ray beamlines. The low emittance of the high brightness ring lattice results in quite short lifetimes, which makes operation in top-off injection mode a necessity. The NSLS-II injection system must be able to provide an electron beam at the high repetition rate and with good injection efficiency. In this paper we present a concept of the NSLS-II injection system and discuss conditions and constraints for the injector design. Various injection system parameters are estimated from the point of view of SR user demand. | ||
| RPAE068 | Very Short Bunches in MIT-Bates South Hall Ring | 3768 |
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Funding: Department of Energy The study of ultra-short bunches in MIT SHR storage ring with very small momentum compactions is carried out. The ultra-short bunches are to greatly enhence the coherent radiation by many orders of magnitude. The ring lattice is resigned to reach very small momentum compaction factor down to 1·10-5 levels. The measurement is performed with the streak camera. The various associated issues are discussed. |
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| RPAE069 | Terahertz Coherent Synchrotron Radiation in the MIT-Bates South Hall Ring | 3783 |
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| We investigate the terahertz coherent synchrotron radiation (CSR) potential of the South Hall Ring (SHR) at MIT-Bates Linear Accelerator Center. The SHR is equipped with a unique single cavity, 2.856 GHz RF system. The high RF frequency is advantageous for producing short bunch length and for having higher bunch current threshold to generate stable CSR. Combining with other techniques such as external pulse stacking cavity, femtosecond laser slicing, the potential for generating ultra-stable, high power, broadband terahertz CSR is very attractive. Beam dynamics issues related to short bunch length operation, and may associated with the high frequency RF system, such as multi-bunch instability are concerned. They could affect bunch length, bunch intensity and beam stability. The SHR is ideal for experimental exploration of these problems. Results of initial test of low momentum compaction lattice and bunch length measurements are presented and compared to expectations. | ||
| RPAE056 | NSLS II: The Future of the NSLS | 3345 |
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Funding: Under Contract with the United States Department of Energy Contract Number DE-AC02-98CH10886 The National Synchrotron Light Source at BNL was the first dedicated light source facility and it has now operated for more than 20 years. During this time the user community has grown to more than 2400 users annually. To insure that this vibrant user community has access to the highest quality photon beams, the NSLS is pursuing the design of a new ultra-high brightness (~10E21) electron storage ring, tailored to the 0.3-20 KeV photon energy range. We present our preliminary design and review the critical accelerator physics design issues. |