• J. Skaritka, J. Bengtsson, G. Danby, G. Ganetis, W. Guo, R.C. Gupta, J.W. Jackson, A.K. Jain, S.L. Kramer, S. Krinsky, Y. Li, W. Meng, B. Nash, S. Ozaki, M. Rehak, S. Sharma, C.J. Spataro, F.J. Willeke
  BNL, Upton, Long Island, New York

Funding: US DOE Office of Basic Energy Sciences

NSLS-II is a new state-of-the-art medium energy synchrotron light source designed to deliver world leading brightness and flux with top-off operation for constant output. Design and engineering of NSLS-II began in 2005 and the beginning of construction and operations are expected to start in 2009 and 2015, respectively. The energy of the machine is 3Gev and the circumference 792 m. The chosen lattice requires tight on magnetic field tolerances for the ring magnets. These magnets have been designed with 3D Opera software. The required multipole field quality and alignment preclude the use of multifunctional sextupoles, leading to discrete corrector magnets in the storage ring. The corrector magnets are multifunctional and will provide horizontal and vertical steering as well as skew quadrupole. This paper describes the dipoles, quadrupoles, sextupoles, and corrector magnets design and prototyping status of the NSLS-II.

• R.P. Fliller, W. Guo, R. Heese, Y. Li, T.V. Shaftan
  BNL, Upton, Long Island, New York

The NSLS II is a state of the art 3 GeV synchrotron light source being developed at BNL. The injection system will consist of a 200 MeV linac and a 3GeV booster synchrotron. The injection system must supply 7.3nC every minute to satisfy the top off requirements. A large booster acceptance is neccessary to have a high booster injection efficiency and alleviate the requirements on linac gun. We also anticipate transverse stacking of bunches in the booster to increase the amount of charge that can be delivered. We present studies of the anticipated booster stay clear including lattice errors and the ramifications for injection efficiency and transverse stacking.

• W. Guo, S.L. Kramer, S. Krinsky, Y. Li, B. Nash, T. Tanabe
  BNL, Upton, Long Island, New York

Funding: NSLS-II, Brookhaven National Laboratory

NSLS-II, the third-generation light source which will be built at BNL is designed and optimized for 3 GeV energy, ultra-small emittance and high intensity of 500 mA. It will provide very bright synchrotron radiation over a large spectral range from IR to hard X-rays. Damping wigglers (DWs) are deployed to reduce the emittance of 2 nm by factors of 2-4, as well as for intense radiation sources for users. The linear and nonlinear effects induced by the DWs are integrated into the lattice design. In this paper, we discuss the linear and nonlinear optimization with DWs, and present a solution satisfying the injection and lifetime requirements. Our approach could be applied to the other light sources with strong insertion devices.

• S.L. Kramer, W. Guo
  BNL, Upton, Long Island, New York

Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886

The NSLS-II light source is a proposed 3 GeV storage ring, with the potential for ultra-low emittance*. The lattice design uses a 30 cell DBA structure with a periodicity of 15, for alternating long and short straight sections. All cells are tuned achromatic to maximize the emittance reduction achieved as damping wigglers are added to the ring. Recent optimization of the lattice consisted of increasing the number of possible hard X-ray beam ports using three pole wigglers, reducing the number of magnets (quadrupoles and sextupoles) and shifting the magnets to allow easier extraction of the photon beams. The impact of the reduction of magnets on the lattice flexibility will be presented in terms of the tuning range possible for the lattice parameters: tune, emittance, and chromaticity, beta function matching to user insertion devices (IDs) and for compensating for ID induced distortions to these parameters. This flexibility is important for optimizing the lattice linear and nonlinear properties, the dynamic aperture, and its impact on beam lifetime, as well as matching the user source requirements and for value engineering of magnets and power supplies.

*Work presented on behalf of the NSLS-II Design Team, CDR(2006), CD2(2007) and CD3(2008).

• C.T. Hliang, D. Robin, F. Sannibale, W. Wan
  LBNL, Berkeley, California
• W. Guo
  BNL, Upton, Long Island, New York

Funding: Supported by DOE BES contract DE-AC03-76SF00098.

Several years ago experiments at the APS demonstrated the possibility of creating crabbed beam through vertically kicking the beam and letting it oscillate for a half of a synchrotron period. Such a crabbed beam would allow the possibility of creating a few ps xrays. At the ALS we have repeated these experiments. In this paper we will present the results obtained and compare them to theoretical predictions.

• B. Nash, W. Guo
  BNL, Upton, Long Island, New York

Successful operation of NSLS-II requires sufficient dynamic aperture for injection, as well as momentum aperture for Touschek lifetime. We explore the dependence of momentum and dynamic aperture on higher-order multipole field errors in the quadrupoles and sextupoles. We add random and systematic multipole errors to the quadrupoles and sextupoles and compute the effect on dynamic aperture. We find that the strongest effect is at negative momentum, due to larger closed orbit excursions. Adding all the errors based on the NSLS-II specifications, we find adequate dynamic and momentum aperture.