• 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, 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.