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Monday 12.7. 03:00 Stable beams 9_6_6_6 09:40 back to ADJUST to switch on damper and switch off octupoles . 10:20 back to STABLE BEAMS. 11:57 beam dumped by LHC VELO when switching back to ADJUST mode after ADJUST handshake. VELO was not fully out.
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Monday 12.7 • 03:00 Stable beams 9_6_6_6 • 09:40 back to ADJUST to switch on damper and switch off octupoles. • 10:20 back to STABLE BEAMS. • 11:57 beam dumped by LHC VELO when switching back to ADJUST mode after ADJUST handshake. VELO was not fully out. • End of a very good fill, luminosities still at 7E29. No problem with damper in stable beams. • 13:40 Access. • S12 QPS fixed. • FMCM threshold increase on RMSD.B1(2). Up by a factor ~ 4 at injection. Rough test with beam is OK (vertical shift of 3 mm on BTV in front of TDE). To be repeated with a complete OFF to the PC (injection). • RF access in P4. 8:30 meeting
Tune spectra damper On-Off 8:30 meeting
Monday 12.7 • 10:00-17:00 SPS multi-bunch cycle • Continued setting up of the cycle with 4 injections. Emittances below nominal. • Adjusted extraction kicker delays to extract ALL 4 bunches. • Extraction to upstream TEDs for both B1 and B2. • Extraction to TI2 downstream ok. • Everything looking ok – next step is injection into the LHC. • 15:00 LHCb with - polarity • 17:00 TDI P2 problem • Does not reach requested setting. Mechanical problem to be fixed today. • TDI in position with help of the piquet. • 17:30 Injection • Large orbit perturbation from LHCb polarity inversion – large local kick at MCBX.1R8. 8:30 meeting
Monday 12.7 • 19:30: Filling 12_8_8_8 9E10/bunch • 20:00: Ramp • 20:45: Flat top • Incorporated RT trims from orbit into settings/functions. Worked partly only – anything changed in the past 2 weeks??? • When the OFB was switched off, the settings of the RT suddenly jumped to NaN for all vertical orbit correctors (????????), horizontal plane OK. • Switching ON/OFF OFB seemed to indicate that it was still working… • 21:20 Squeeze • Beam lost due to vertical orbit change: the OFB did not act in vertical. • Beam dumped by losses in IR7 (84 s RS on MQWA). • 23:00 Setup • MKI problem IR8 – faulty after pressure rise. • 00:30 Injection 8:30 meeting
Tuesday 13.7 • 02:00: Again some issue get the OFB ON • 02:30: Ramp • 04:00: Squeeze • OFB off by itself while squeezing. Orbit change moderate and beam survived. Manual correction at 7 m, then OFB on again. • 05:20 Stable beams fill 1224 • L 1.4E30 cm-2s-1. • Some beam loss after ATLAS lumi scan. • Strong losses correlated with lines at 0.315 in Q spectrum. 8:30 meeting
Fill 1224 8:30 meeting
Tune spectrum lines… 8:30 meeting
Tuesday 13.7 • Keep this fill for some time, try again damper. • Multi-bunch injection studies later today. • Fill overnight. • Check OFB issues during the day (start with offline checks). 8:30 meeting