LHC Progress Friday 30 th October 2015 Coordination Week 44: Massimo Giovannozzi, Wolfgang Hofle, Jorg Wenninger

Plan of the day 30/10/2015 LHC Morning meeting – WH & JW 2 skipped + BI test done beam lost in ramp being prepared, injectors checking

Thursday daytime Set-up of 2.51 TeV cycle for reference run ramp with probes – 8:10 probes in – 12:20 collide & TeV to 4 m – Q, Q’ orbit  ok – Beta beating < 20% – Ready for nominals: to do’s Align TCTs, find collisions MPS validation at FT and in collisions Intensity ramp up and, Q, Q’ for high intensity 30/10/2015 LHC Morning meeting – WH & JW 3

Feedbacks (2.5 TeV cycle) 30/10/2015 LHC Morning meeting – WH & JW 4 Feedbacks behaved and Fidel model after ramp down to 450 GeV ok.

Flat Top RF TeV 30/10/2015 LHC Morning meeting – WH & JW 5 For dispersion measurement

Beam 1: Optics at 2.5 TeV 30/10/2015 LHC Morning meeting – WH & JW 6

Beam 2: Optics at 2.5 TeV 30/10/2015 LHC Morning meeting – WH & JW 7

Thursday p.m. Check of Beam Intensity measurement sensitivity to bunch length – 450 GeV, 12 bunches – Change bunch length by RF voltage trim at Several trips of RF for beam 2 Beam 2 voltage changed in steps between 3 MV and 9 MV 30/10/2015 LHC Morning meeting – WH & JW 8

Thursday evening night Filling for Physics – 18:20 TDI B2 vacuum dumped during filling (increased to 1e-5) 2 pumps went off Vacuum Piquet restarted pumps – 20:30 Dumped again by vacuum of TDI B2 Exceeded interlock level with beam 2 with 2/3 of total number of bunches After discussion between equipment experts thresholds for vacuum increased by 25% to 1e-5 – CBCM issues with multiple requests to SPS 30/10/2015 LHC Morning meeting – WH & JW 9

Thursday evening night Filling for Physics 1:30 TDI B2 vacuum not recovering and dumping beam while filling – 2e-5 measured after last injection 4:20 Machine full and ramp started Mismatch of RF functions (prepare for ramp) 5:40 beams GeV After long wait time at 450 GeV Beam 2 losses (BLM IR7) 7:40 MKI 2.D faulty, piquet called, extended soft start 30/10/2015 LHC Morning meeting – WH & JW 10

TDI B2 vacuum 30/10/2015 LHC Morning meeting – WH & JW 11 Beams dumped several time at 450 GeV while filling over night 1:30 a.m. 1e-5 1e-6 1:00 a.m.

Fill 4554: Dumped by BLM IR7 30/10/2015 LHC Morning meeting – WH & JW 12

Plans and options Test of 2.51 TeV cycle - settings ready  probes done BCMS is ready  take with 601 bunches, ramp + Physics if injection ok – 25ns_601b_589_438_459_96bpi9inj_bcms (250 ns gap between 48’s) – 25ns_601b_589_522_540_48bpi15inj_bcms (back-up) Physics with 2244 bunches Second test with asymmetric filling (1825b in B2, 12b in B1) End of run last minute test requests: – Injection with inverted tunes (0.31/0.28) to understand the source of electron cloud (dipoles/quads) – e-cloud team. – 50 Hz from PCs – G. Arduini 30/10/2015 LHC Morning meeting – WH & JW 13

BCMS Filling scheme 30/10/2015 LHC Morning meeting – WH & JW 14 Injection kicker length to be adjusted

To do list 30/10/ b4eDone short fill SB & 1593b to FT BCMSType test  next ADT full bandwidthGA request  skip ? ULO scanTowards the end Reference heat loadBefore TS3 Check deconditioning at 450 GeVAfter TS3 Heat load with single beams to FTB1 done, B2 1824b with wire scans in B1 with 12 bunches Bunch flattening tests in SBDone First look at 2.51 TeVDone with probes, optics at 2.5 TeV DoubletPushed to 2016 LHC Morning meeting – WH & JW