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LHC Nominal injection sequence. Mike Lamont Acknowledgements: Reyes Alemany Fernandez, Brennan Goddard. Nominal injection. Overall injection scheme Pilot R1, Pilot R2, Intermediate R1 – Optimise Intermediate R2 – Optimise Dump & re-inject pilot R1 Dump & re-inject pilot R2
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LHC Nominal injection sequence Mike Lamont Acknowledgements: Reyes Alemany Fernandez, Brennan Goddard
Nominal injection • Overall injection scheme • Pilot R1, Pilot R2, • Intermediate R1 – Optimise • Intermediate R2 – Optimise • Dump & re-inject pilot R1 • Dump & re-inject pilot R2 • Interleafed nominal injection R1/R2 LHCCWG - injection
Mode: Setup Mode:Pilot Injection LHCCWG - injection
Mode: IntermediateInjection Mode:NominalInjection LHCCWG - injection
Injection plateau – no beam LHCCWG - injection
Injection plateau – no beam - RF LHCCWG - injection
Injecting pilot – R1 LHCCWG - injection
Circulating pilot R1/R2 LHCCWG - injection
Inject intermediate – R1/R2 LHCCWG - injection
Circulating intermediate LHCCWG - injection
Re-inject pilot– R1/R2 LHCCWG - injection
Inject nominal – R1/R2 * See Verena’s presentation at PM workshop LHCCWG - injection
Implicit LHCCWG - injection
Triggered data acquisition at injection • Beam based information: • Beam loss monitors (snap-shot, 1..2 seconds?) • BCT and FastBCT snap-shot • Radiation monitors • 2 seconds of tune/coupling trace (1 second before/1 second after) • 2 seconds of orbit, including some r.m.s. calculations for specific regions (e.g. collimation) • 2 seconds of chromaticity trace • bunch length of selected bunch (bes), RF voltage -> momentum spread • transverse beam profile (/emittance) • (time stamp of the event) • Some more hardware status information: • position of movable objects in the LHC (collimators, screens, Roman Pots) • temperature of the most important cryo-circuits (indicates also losses) • tunnel temperature (esp. in IR3 and IR7) • SPS/LHC injection momentum mismatch (energy feedback) • Number of people in the CCC. • Status/current of the main lattice circuits (main bends/quads) • Status of the BIC, QPS, SIS, Ralph Steinhagen LHCCWG - injection
Events Julian Lewis & friends LHCCWG - injection
Injection Event Table A variation will be played at each injection. Telegrams (ring, beam type, next bucket etc.) also going out LHCCWG - injection
CBCM API – injection request • Error = Set Next Injection Beam Type: Beam Type • OK, Not in Filling-Mod, Wrong LIC settings (LIC LHC Injector Chain) • The value is checked against the beam type in the SPS telegram - if its not the same; then the BTNI parameter is set to NO-BEAM in the LHC telegram. • Error = Set Next Injection Ring: Ring • OK, Not in Filling-Mode, Out of Range 1..2 • If the HLLSA sets the wrong value an out of range error is returned, and the RNGI parameter in the LHC telegram is forced to zero. • Error = Set Next Injection RF Bucket: RF Bucket 1..35640 • OK, Not in Filling-Mode, Out of Range 1..356402 • If the HLLSA sets the wrong value an out of range error is returned, and the BKNI parameter in the LHC telegram is forced to zero. • Error = Set CPS Batches: Batches 1..4 • OK, Not in Filling-Mode, Out of Range 1..4 • If the HLLSA gets this value wrong an out of range error is returned, and the internal variable controlling the number of injected CPS batches is set to zero. All subsequent CPS beams are dumped. (Modification in the CBCM needed here). Julian Lewis LHCCWG - injection
RF - injection • LHC RF system expects the bunch number and the destination ring to be delivered to SR4 by the LHC timing system. • This would be delivered every SPS cycle whenever the LHC is in injection mode. • The LHC be the master for the SPS-LHC transfer. • The SPS receives a train of pulses at the SPS-LHC common frequency. With its bucket selector the LHC can select the position for transfer from the SPS. • RF system updates the bucket selector and the phase of the 400 MHz sent to the SPS. • Fine positioning of the beam injection phase in the LHC buckets is adjusted with the phase of the LHC RF signal sent to the injectors. • Signals for RF synchronization must be available in the PS about 450 ms before extracting to the SPS. • RF generates injection pre-pulses LHCCWG - injection
P. Baudrenghien LHCCWG - injection
Conclusion • Timing requirements agreed (more-or-less) • Interface to timing system (Version 0) defined • Testing should start so • Loose FSM approach to defining LHC sequence • Work in progress • A first version of LHC “beam modes” defined. LHCCWG - injection