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1/4/2004 TT2A target test PS BEAM performanceM.Giovannozzi, C.Carli, S.Gilardoni, K.Yoshimura, S.Hancock, H.Kirk, A.FabichCC presented two slides telling the scheme of possible PS bucket filling, pulse lenghts and batch compression. Additional comments: - PSB run in h=1 is best suited for maximum flexibility to fill the buckets of PS - intensities: 5*10^12/bunch can be expected, 7*10^12/bunch is possible, but needs several MD weeks; there we could profit from the R&D done for CNGS. A typical cycle would contain four bunches. - fill all eight PS buckets 1) PSB in h=2 and each bucket at half intensity 2) filling with double cycle <-> demand for more beam time (two subcycles instead of one) - nTof receives 7*10^12/bunch in dedicated mode, half of it in parasitic mode, nToF runs only at 20 GeV/c - the beam elements of the nToF line can transport up to 24 GeV/c - the four rings of the PSB can be distributed in ANY scenario on the eight buckets of the PS - TT2A target experiment desires pulse length at full intensity from 0.5 to a few microseconds - for 20*10^12 the pulse length can be minimum about 900 nanoseconds, for 15*10^12 one could use bunch compression to achieve pulse-lengths of about 350 nanoseconds (needs R&D!, 2 men-months) - maximum pulse length: see comment below by MG - simulation on TT2A spot size and impact of TT2A beam windows on the nToF spot size needed - 20 GeV/c is preferred momentum due to: > running parasitic with nToF and due to the DC magnets > kicker strength - bunch compression from 13 to 6 ns r.m.s. is not envisaged, would only increase the spot size (KH: factor 3) and the bunch length is short enough for the physics case. - PS could easily switch between operation for nToF and TT2A within cycles, if run at the same beam momentum - manpower: setting up a "standard beam" needs a few men*days, and during beam operation on TT2A target one person permanently present (~1 men*month). Additional menpower is required for special demands on beam performance as mentioned above. MG: I had a discussion with the experts (operation and kicker) for the issue of multi-kicks. R. Steerenberg told me that the strength necessary to extract the beam at 20 GeV/c corresponds to 700 kV. K.-D. Metzmacher told me that there are twelve generators, each delivering about 80 kV. Therefore, using according to this information we can RULE OUT the possibility of having a SECOND KICK one turn after the first extraction. -> maximum pulse length limited to 2 microseconds |