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 2
Mode: Setup Mode: Pilot Injection LHCCWG - injection 3
Mode: Intermediate Injection Mode: Nominal Injection LHCCWG - injection 4
Injection plateau no beam On entry Check power converter settings Check RF 400 MHz ON - 8 MV; RF frequency Load LFB, TFB settings Monitor power converters Set TDI settings parked Set collimators parked Set TCDQ parked Injection kickers ON Start auto harmonic decay correction Check and monitor transfer lines Beam dumps Ready Set BPM gains to pilot, set capture bunch and turns Check Beam interlock system Change injection master to LHC LHCCWG - injection 5
Injection plateau no beam - RF 400 MHz ON - 8 MV. Set RF frequency program to injection level Set the gain of the phase loop amplifier to filling value Set the gain and time constant of the synchronization loop amplifier to the filling value Close the phase loop around the VCO Switch the RF DRIVE ON Switch the phase loop to the cavity sum signal Reset the revolution frequency generator Check synchronization. LHCCWG - injection 6
Injecting pilot R1 On entry On event Check settings Load and/or check injection timing table [BCT, BPMs, BLMs, SRM] Make request to CBCM with ring, bucket number, PS user (intensity) and number of PS batches Injection into LHC - injection kickers, BI receive prepulses. BST sends out acquisition event for BPMs, BLMs as required. LFB,TFB,RF: Batch dependent settings triggered by timing events. Jump phase loop onto beam (beam/cavity sum) Switch synchro loop on LHCCWG - injection 7
Circulating pilot R1/R2 BPF SBF Entry False True Exit True True On entry On entry On entry On exit Check first turn, energy offset, beam loss, intensity, emittance, RF response, longitudinal emittance Check BLMs, trajectory in transfer line Measure tune, orbit, chromaticity Configure and start global orbit feedback Monitor lifetime, beam losses Monitor harmonic correction TDI,TCDQ to coarse Collimators to coarse Change mode LHCCWG - injection 8
Inject intermediate R1/R2 BPF SBF Entry True True Exit True False On event Check settings Monitor transfer lines Monitor pilot (check harmonic correction) Load LFB, TFB, RF settings Check timing table Set BPM gains to pilot, set capture bunch and turns Set Safe Beam Flag false Intermediate injection request Injection into LHC LHCCWG - injection 9
Circulating intermediate BPF SBF Entry True False Exit True False On entry On entry On entry On event On exit Check first turn, energy, beam loss, intensity, emittance, RF response, longitudinal emittance Check checks on BLMs, trajectory in transfer line Measure & correct tune, orbit, chromaticity Monitor lifetime, beam losses Fine adjustment: TDI to protect Fine adjustment: Collimators to protect Fine adjustment: TCDQ to protect Check crossing angle, separation, compensation Monitor pilot (check harmonic correction) Lifetime problems, high beam loss abort Change mode LHCCWG - injection 10
Re-inject pilot R1/R2 BPF SBF Entry True False Exit True False On event Check settings Monitor transfer lines Set BPM gains to pilot, set capture bunch and turns Load LFB, TFB settings Load disable PM timing table Dump beam [BPF to false] Re-enable PM LBDS XPOC Pilot injection request Injection into LHC [BPF to true] Check injection LHCCWG - injection 11
Inject nominal R1/R2 BPF SBF Entry True False Exit True False On entry On event Check settings Monitor transfer lines Monitor pilot (check harmonic correction) Set BPM gains to pilot, set capture bunch and turns Load LFB, TFB settings Load & Check timing table Intermediate injection request Injection into LHC ICQ*: abort gap, beam loss, lifetime, energy mis-match, injection oscillations, trajectory in lines, mountain range, beam sizes Measure tune, chromaticity, orbit, beam sizes, lifetimes, abort gap * See Verena s presentation at PM workshop LHCCWG - injection 12
Implicit On event TDI, TCDQ, Collimators not at Inhibit injection protect On event Beam permit pulled Both beams dumped On event ICQ fails Inhibit injection On event Injection BIS inhibit Hold sequence On event Cryo not OK Hold sequence On event Vacuum not OK Hold sequence On event SPS extraction inhibit Wait On event etc etc LHCCWG - injection 13
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 14
Events HX.BTNI 0x1401FFFF Next injection beam type HX.BPNM 0x1402FFFF Basic Period Number HX.BKNI 0x1403FFFF Next injection RF bucket HX.RNGI 0x1404FFFF Next injection ring HX.ENG 0x1405FFFF Beam energy HX.INT1 0x1406FFFF Beam intensity - Ring 1 HX.INT2 0x1407FFFF Beam intensity - Ring 2 HX.SBF1 0x1408FFFF Safe beam flag - Ring 1 HX.SBF2 0x1409FFFF Safe beam flag - Ring 2 HX.MODE 0x140AFFFF What the LHC is doing HX.FILLNUM 0x140BFFFF Fill number HX.BTC1 0x140CFFFF Circulating beam type - Ring 1 HX.BTC2 0x140DFFFF Circulating beam type - Ring 2 HX.DISPM1 0x14210000 Disable Post-Mortem Ring 1 HX.DISPM2 0x14220000 Disable Post-Mortem Ring 2 HX.ENBPM1 0x14230000 Enable Post-Mortem Ring 1 HX.ENBPM2 0x14240000 Enable Post-Mortem Ring 2 HX.DUMP1 0x14250000 Dump ring 1 HX.DUMP2 0x14260000 Dump ring 2 HX.PM1 0x14270000 Postmortem ring 1 HX.PM2 0x14280000 Postmortem ring 1 HIX.FW 0x14290000 Injection forewarning (Currently 1S) HX.SRMP-POW 0x142AFFFF Start ramp power converters HX.ARMP-POW 0x142BFFFF Abort ramp power converters HIX.REQ-RF 0x142CFFFF RF Injection request HX.SFRMP-RF 0x142DFFFF Start frequency ramp RF HX.SVRMP-RF 0x142EFFFF Start voltage ramp RF HIX.STFB-RF 0x142FFFFF Start TFB injection RF HIX.SLFB-RF 0x1430FFFF Start LFB injection RF HX.SYNC-RF 0x1431FFFF Synchronize rings RF Julian Lewis & friends HIX.W100 0x1432FFFF Warning injection 100ms (900ms after HIX.FW) HIX.W20 0x1433FFFF Warning injection 20ms (980ms after HIX.FW) HIX.AMC 0x1434FFFF Injection NOW (Acquisition master C, 1S after HIX.FW) HIX.APOST 0x1435FFFF Injection +10ms (1010 after HIX.FW) HX.RPLS 0x14FE0000 Ready telegram MX.CTRIG 0x0100FFFF The millisecond event LHCCWG - injection 15
Injection Event Table Injection forewarning (Currently 1S) -1000 Warning injection 100ms (900ms after HIX.FW) 100 Warning injection 20ms (980ms after HIX.FW) -20 Injection NOW (Acquisition master C, 1S after HIX.FW) 0 Start function TFB 0 Start function LFB 0 BLM snapshot 0 SRM 0 BPM capture 0 Injection +10ms (1010 after HIX.FW) 10 A variation will be played at each injection. Telegrams (ring, beam type, next bucket etc.) also going out LHCCWG - injection 16
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 17
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 18
sps frev f c = = 27 f 7 lhc rev P. Baudrenghien LHCCWG - injection 19
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 20