|
Date
|
Summary
|
Link to report from morning meeting
|
|
Monday 9th April |
- 4:50 Ramping down ALICE solenoid and dipole (+compensators)
- 7:32 beams dumped during squeeze by BLM at TCLA.D6L7 RS 1.3
sec (losses on B2).
- next: 624 bunches (6 hours stable beams with ALICE off)
till Tuesday morning
|
9:00 meeting |
|
Sunday 8th April |
- 0:48 – 5:09 Fill 2488 stable beams (264 bunches). Changing
luminosity at ATLAS and CMS by separating the beams (1st hour
75%, 2nd hour 100%, 3rd hour 75%, 4th hour 100%). Average
intensity at start of ramp: 1.34x1011 ppb and at
start of stable beams: 1.31x1011 ppb. Initial maximum
luminosity: 9.6x1032cm-2s-1,
total delivered luminosity: 10.5 pb-1.
- 7:17 Fill 2489 stable beams (264 bunches). Changing
luminosity at ATLAS and CMS by separating the beams (1st hour
95%, 2nd hour 100%, 3rd hour 95%, 4th hour 100%)
- 14:54 – 16:10 Fill 2490 (264 bunches) stable beams. Average
intensity 1.5e11 per bunch. Initial luminosity: 11e32cm-2s-1.
Losses not higher than 10-15% of dump thresholds all along the
cycle (below 10% on RS 1.3s during collisions BP). 5
pb-1delivered luminosity.
- 18:20 – 4:37 Fill 2491 stable beams (624 bunches). Average
intensity 1.4e11 ppb. Initial luminosity: 24e32cm-2s-1. 60
pb-1delivered luminosity.
|
9:00 meeting |
|
Saturday 7th April |
- 02:00 Fill #2482 STABLE BEAMS (1.3x1011 p/b) and
264 bunches with initial luminosity of >0.9x1033 cm-2
s-1.
- 05:30 End of fill #2482
- 08:00 Problem with the orbit feedback - investigating
- 12:13 Fill 2485 (3 bunches test fill) dumped by another OFSU
problem during squeeze
- Fill 2485: Corrected the beam process for going to LHCb
tilted crossing without having head-on collisions at LHCb.
Tested successfully.
- Loss maps: B1 H + V, B2 H + V + longitudinal (-500 Hz)
- 19:17 – 20:47 stable beams fill 2486 (84 bunches). Average
intensity at start of ramp: 1.35x1011 ppb and
at start of stable beams: 1.33x1011 ppb. Initial
luminosity: 2.9x1032cm-2s-1.
1.4 pb-1delivered in 1:36 hour.
- 22:00 - 23:23 no beam from SPS: trip of main power supply
|
9:00 meeting |
|
Friday 6th April |
- 00:18 End of fill #2472. 3.5 pb-1 in 4:24 hours (OP dump)
- 01:00 – 01:50: no beam form LINAC2
- 01:50-07:30 Damper setting-up for 1.4x1011
p/bunch
- 07:30-10:30 Asynchronous damp test.
- FIDEL update. Now chromaticity decay
corrected.
- 12:13 Beam dump due to problem in the storage
of the reference for the orbit feedback.
- Issues with RF cogging
- 15:00 STABLE BEAM #2479. Initial luminosity
3.5x1032cm-2s-1
- 17:45 end of fill #2479: 2.9 pb-1
in 3:45 hours
- •19:00-00:00 Fills (2480 and 2481) with 264
bunches/beam and bunch intensity close to 1.5x1011
p/b. Work on losses in the squeeze and stabilization.
|
9:00 meeting |
|
Thursday 5th April |
- 00:38 – 2:04 first stable beams 4 TeV (3 on 3 bunches)
(#2469) Initial luminosity 7.8x1030cm-2s-1
- 02:04 End of fill#2469. 39 nb-1 in 1:50 hours.
- 5:40 - 9:41 Stable Beams 47 bunches (Atlas low pile-up,
Alice satellite-main collisions; 11 indiv bunches 8-9E10 and 3
trains of 12 nominal bunches). Initial luminosity 8.1x1031cm-2s-1. Dumped by CMS BCM.
- 09:41: End of fill #2470. 1100 nb-1 in 4 hours
- Problems with the following injection due to to intermittent
loss of communication with the FGC. Traced back to an issue with
a client of the FGC acquisition (Luminosity scan application).
- 15:27 STABLE BEAMS #2471 (47 on 47 bunches). Initial luminosity:
8.7x1031cm-2s-1
- 17:47 End of Fill #2471. 540 nb-1 in ~2:15 hours
- 19:54 Stable beam #2472. (84 on 84 bunches): Initial
luminosity: 2.9x1032cm-2s-1
|
8:30 meeting |
|
Wednesday 4th April |
- 00:00-04:00 BI setting-up for 50 ns
- 04:11 Trip of Q4.R8. MP3 piquet called.
Pre-cycle.
- 08:30 Access for QPS for Q4.R8 for reset of
QPS card.
-
10:30-11:40 No beam from the injectors due to unplanned intervention
on RAMSES software and SPS extraction septum problem (beam 2)
-
Ramp-Squeeze for chromaticity measurement and verification of
the beta*-energy limits. Chromaticity correction during the ramp
very good. Still to be improved at flat-top.
-
Energy interlock on the TCTs at IP8 during the squeeze.
Corrected.
-
Ramp with new parameters for decayy and snap-back correction (FIDEL) and
aperture checks with squeezed optics: problems with the
FIDEL parameters, losses at the beginning of the ramp
- Revert back to previous FIDEL correction version.
-
14:28 Spurious trigger of the unmaskable BLMs in point 2
-
16:00 Spurious trigger of CMS BCM ==> Expert contacted.
-
16:30-21:30: Aperture verification at the end of squeeze
and in collision. Aperture sufficient to run with 60 cm optics.
- 23:00 Injecting.
-
Next: Stable Beams with 3 on 3 bunches
|
8:30
meeting
|
|
Tuesday 3rd April |
- 08:00 Loss maps + asynchronous dump tests at
injection
- Ramp and squeeze with probe beams for
chromaticity correction (including setting-up of the b3 decay
correction at flat-top). Beam 2 lost in the squeeze from 1 m.
Reason: radial modulation and loss of the lock of the phase loop
- 12:07 Trip of Q4.R8 due to noise on the HTS
quench protection system.
- 15:00 Asynchronous dump tests at injection
- 15:30-24:00: Setting-up of the 50 ns
injection: up to 144 bunches/pulse injected. Some vacuum
activity observable at MKI and TDI areas
|
8:30 meeting |
|
Monday 2nd April
|
- 06:00 Dump qualification test at 2 TeV.
- 08:00 Access to
prepare for stable beams (PC, BBQ Pt 4, cryo Pt 2 insulation vacuum,
BLM Pt 2+8, experiments)
- 13:00 machine closed,
RQTL10.R3B2 tripped, pre-cycle
- 14:30 RF blow-up test
ramp with new blow-up functions
- Test of the b3 knob
for chromaticity decay correction
- Loss maps at the end
of the squeeze (betatronic and asynch dump test)
- 20:30 Ramp with
old-blow-up. Still some issues with the control from the sequencer
- Loss maps +
asynchronous dump test in collision over night
|
8:30 meeting
|