Presentation on theme: "LHC Injection in 07 “Summer MD-Planning” Milorad Popovic."— Presentation transcript:
LHC Injection in 07 “Summer MD-Planning” Milorad Popovic
Outlook General Remarks, Visits Heiko Damerau before PAC07 Elias Metral, Massimo Govannozzi after PAC07 Linac Debuncher Phase? PSBooster PS SuperPS Linac-Space Charge LHC@FNAL
From e-mail-Damerau ……I also wanted to come back to you with respect to the longitudinal blow-up in the CPS. The ESME simulations of the AD beam are quite close to reality now. I use a Mathematica script which generates a long ESME input file so that the modulation is generated as it should in the simulations. Apparently there are two ingredients to get them close to the measurements: space charge and a blow-up voltage that might be some 25% larger than what we think (in fact, the operational shunt impedance of the 200 MHz cavities, including amplifier, short circuit transmission lines, damping, etc. are not well known). …..The spread from the linac has not yet been tried.
Longitudinal Emittance Blow-up in the PS 08 December 2006 H. Damerau Acknowledgments: W. Höfle, T. Linnecar, A. Marmillon, M. Morvillo, M. Popovic (FNAL), E. Shaposhnikova, J. Tückmantel, J.- L. Vallet Accelerator Performance Committee
5 Three longitudinal blow-up options in the order of priority: 1.Optimize the blow-up with 200 MHz system to operate with three cavities only → AD first, then other beams 2.Explore the performance of the blow-up with an 80 MHz cavity → Further MDs in 2007 3.Find “good noise” (well adapted modulation signal) for the blow-up using phase modulation of the main RF system Blow-ups in 2007 (assuming larger voltage per cavity): Try low-energy blow-up with three RF cavities Keep one 200 MHz cavity as a hot spare Keep remaining two (not renovated) cavities untouched If successful → Two cavities to be removed 2007/2008 Outlook
From Gianluigi, e-mail Did you find some time to discuss woth you r colleagues in Fermilab about the possibility of contributing to the simulation of the space charge issues in the PSBooster for an H- injection at 160 MeV (LINAC4)? By the way: we made some progress in the understanding of the instability of the LHC beam in the PS: we have found that one of the 40 MHz cavities used for this beam was indeed delivering a voltage different form the expected and it was therefore generating shorter bunches. In that case the LHC beam is getting unstable under the influence of electron cloud. We are still analyzing the data but I'll keep you ineformed of the progress. Many thanks for your help during your stay at CERN Cheers Gianluigi