• R.P. Fliller, R. Heese, S. Kowalski, J. Rose, T.V. Shaftan, G.M. Wang
  BNL, Upton, Long Island, New York

The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster synchrotron. The injection system needs to deliver 7.5 nC in 80 - 150 bunches to the storage ring every minute to achieve current stability goals in the storage ring. This is a very stringent requirement that has not been demonstrated at an operating light source, though it should be achievable. To alleviate the charge requirement on the linac, we have designed a scheme to stack two bunch trains in the booster. In this paper we discuss this stacking scheme. The performance of the stacking scheme is studied in detail at injection and through a full booster ramp. We show the the ultimate performance of the stacking scheme is similar to a single bunch train in the booster if the linac emittance meets the requirements. Increasing the emittance of the linac beam degrades the performance, but still allows an overall increase of train charge vs. one bunch train.

• T.V. Shaftan, A. Blednykh, Y. Kawashima, S. Krinsky, J. Rose, L.-H. Yu
  BNL, Upton, Long Island, New York

Booster extraction presents a number of problems that include strengths and waveforms of the pulsed magnets and design of the vacuum chamber. Instabilities in the booster extraction may compromise the extracted beam quality deteriorating value of high-performance injector design. Here we discuss requirements and tolerances for the extraction system components and methods of increasing its performance.

• A. Blednykh, W.X. Cheng, R.P. Fliller, Y. Kawashima, J. Rose, T.V. Shaftan, L.-H. Yu
  BNL, Upton, Long Island, New York

In this paper, we present an overview of the impact of collective effects upon the performance of the NSLS-II booster.

• Y. Kawashima, J. Cupolo, H. Ma, J. Oliva, J. Rose, R. Sikora, M. Yeddulla
  BNL, Upton, Long Island, New York

The booster synchrotron for NSLS-II accepts beam with 200 MeV from a linac and raises its energy up to 3 GeV. In order to raise beam energy up to 3 GeV, a 7-cell PETRA cavity is installed. Beam instabilities related with the cavity are discussed. In particular, in order to avoid coupled-bunch instability, we consider that cooling water temperature for the cavity should be changed to shift frequencies of higher order modes (HOM) to avoid beam revolution lines. To obtain the relation between the temperature dependence of amount of frequency shift in each HOM and cavity body temperature, we carried out the measurement by changing cavity body temperature. From the measurement data, we calculate the required temperature variation. We summarize the results and describe the system design.

• R.P. Fliller, W.R. Casey, R. Faussete, H. Fernandes, G. Ganetis, R. Heese, H.-C. Hseuh, P.K. Job, B.N. Kosciuk, R. Meier, D. Padrazo, I. Pinayev, J. Rose, T.V. Shaftan, O. Singh, J. Skaritka, C.J. Spataro, G.M. Wang
  BNL, Upton, Long Island, New York

The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster synchrotron and associated transport lines. The transport lines need to transport the beam from the linac to the booster and from the booster to the storage ring in a way that provide high injection efficiency. In this paper we discuss progress on specifying and prototyping the NSLS-II transfer lines including diagnostics, magnet specifications, and safety systems. Commissioning plans are also discussed.

• T.V. Shaftan, A. Blednykh, W.R. Casey, L.R. Dalesio, R. Faussete, M.J. Ferreira, R.P. Fliller, G.S. Fries, G. Ganetis, W. Guo, R. Heese, H.-C. Hseuh, Y. Hu, P.K. Job, E.D. Johnson, Y. Kawashima, B.N. Kosciuk, S. Kowalski, S. Krinsky, Y. Li, H. Ma, R. Meier, S. Ozaki, D. Padrazo, B. Parker, I. Pinayev, M. Rehak, J. Rose, S. Sharma, O. Singh, P. Singh, J. Skaritka, C.J. Spataro, G.M. Wang, F.J. Willeke, L.-H. Yu
  BNL, Upton, Long Island, New York

We discuss status and plans of development of the NSLS-II injector. The injector consists of 200 MeV linac, 3-GeV booster, transport lines and injection straight section. The system design is now nearly completed and the injector development is in the procurement phase. The injector commissioning is planned to take place in 2012.