Link to report from morning meeting
Sunday 9th October
programmed dump after 17:17 hours in stable beams. : integrated
luminosity Atlas/CMS/LHCb: 115/120/21.3 pb-1; Alice: 58.5 nb-1
injecting physics beams
Extraction kicker problem for B1 in the SPS.
beams dumped (B2 already fully injected) as the SPS cannot deliver beams
stable beams Fill #2197 Initial luminosity: 3.42E33 cm-2 s-1!
Slightly higher bunch intensities (1.35E11p) and again an excellent beam
from the injectors!
Beams dumped. Trip of S56, PIC communication lost.
Saturday 8th October
- 01:44 Injection for physics.
Kicker problem solved. Injection efficiency is affected by a BPM
interlock in SPS-LSS6 for B1. SPS problems. Injected beam dumped.
- 03:00 Injection for
- 03:51 Ramp.
- 04:33 Stable beams.
Fill #2194. Initial luminosity: 3.2e33.
- 05:10 Beams dumped by
trip of sector 56. MP3 investigating. Integrated lumi:
7pb-1. Ramp down and recycle.
- 07:41 Access to point
6 (QPS problem) and point 2 (ALICE).
- 08:50 Precycling.
- 10:00 injecting probe
- 11:41 Stable Beams
Fill #2195. Initial luminosity: 3.3e33.
Friday 7th October
- 02:30 preparation of
25ns physics, 60 bunches/beam
- 05:23 stable beams
Fill #2186 (emittance in collision ~3.3um, bunch length 01.32/1.38ns, lifetime
125 hours) peak lumi ~0.06e33 cm-2 s-1
- 08:16 dumped by RF; integrated lumi 0.6 nb-1.
- 09:14 BIC problem in
TI8 and CMS recovering their tracker
- 10:09 Abort gap
- 16:29 End of abort gap
cleaning. Dump. Rampdown and precycle.
- 16:58 RF lines 7B1,
7B2 and 8B2 have an error on the LL.
- 17:59 RF back. Checks
for the new XPOC release.
- 18:32 Injection. Beam
2 injection problems. Transfer line steering. MKI8 faults. TI2 BPM LSS6
- 22:20 Machine filled.
- 22:29 Beams dumped.
Trips 2 RF modules, arcs detected. Ramp down and precycle.
- 23:28 Injection.
Injection problems. SPS injection oscillations. MKI8 faults.
- 23:55 Called kicker
expert. The problem with the MKI is that now there is a shift between
the prepulse and the abort gap keeper. Expert comes to CCC to correct
the shift. RF checked that all OK from their side.
'general power off'
Thursday 6th October
Accidental switch off LHC magnets including experiments
in all IPs except IP3 (EL, CV, RF, ADT, vacuum, optical fibers, EPC,
diamond BLM, vacuum, QPS and CNGS)
Patrol in Pt2 (end of vacuum intervention on TED)
beam back for 25ns MD
02:30 very successful 25ns MD (injection train of 288 bunches B2, 144
bunches B1; 732 bunches circulating B2 with 5h lifetime; ecloud, vacuum
and cryo activity)
Wed 5th October
- 05:31 Beam dump due to
QPS trigger in sector 78. Quench heaters discharged in MB10.L8.
- 07:28 Quench heaters
charged ok again in cell B10L8. Was a EN/EL circuit breaker (cell 32,
EOJ106/78.32R7). nr. Q3.
- 08:29 Cryo back.
- 08:20 RF tests without
beam. Check for problem of debunching observed
during fill #2182.
- 09:51 Vacuum leak in
TI2 TED bellows. Access breaks patrol. Initial estimate for repair and recovery:
- 15:16 Open LHC for
access. ELQA access in P8. Planning for beam 2 program over night: abort
gap cleaning and 25ns setup.
- 18:09 Vacuum group
identifies correct spare part. Recovery time revised to Thursday
morning. TED repair starting. Beam 2 program for the night cancelled.
Plan TI8 stability checks overnight (during pump down of TI2).
- 18:32 Starting the
PNO.a7 on RQ5.L8 and RQ6.L8.
- 19:03 Going through
access list to check who wants to go into LHC over night and during
- 20:10 Access in P8 (vac expert + RP) for preventive check of the TED
bellows in TI8.
Tuesday 4 October
- 12:12 Fill #2181
testing new tuner firmware in preparation for the 25ns MD on Thursday
- 14:00 RF problem
(rollback to previous firmware version)
- 14:50 BLM problem
gap cleaning MD moved to Friday afternoon
- 17:53 injection for
- 19:48 start of ramp
- 20:36 stable beams
Fill #2182 (1.8E14 protons, peak lumi ~3.2e33 cm-2
Mon 3rd October
Operator dump fill #2178, integrated lumi 107/108/18 nb-1. Trip of RQ4.R6
(fire heaters discharged) just after the beam dump but the QPS gave no
Try to reset Q4.R6. Not possible. Access needed.
Prepare access to UA area in point 6.
Prepare tunnel access in point 6.
Lost cryo conditions in the MSR6.
Q4.R6 problem solved (~5h impact). The firing of the heaters has somehow
affected the current lead instrumentation. Could not reset the QPS of
the Q4. Was issue with the ELQA proximity box, on the current lead side.
The fault was cleared by de-plugging and re-connecting the cable but it
is not clear what the source was. The QPS and ELQA teams are still
working to try and understand more in details what happened.
Pre-cycle. Some RF cavity studies (Philippe). Some BLM thresholds
Optimization of transfer line is required (~1h impact).
Injector beam optimization (~0.7h impact).
Stable beams. Fill #2180. Peak lumi ~3.2e33
Beams dumped due to high losses in IR2 after vacuum spike.
Stable beams. Fill #2181. Peak lumi ~3.2e33 cm-2 s-1.