CMS had a fast abort of their solenoid on Friday morning. 3 to 4 days to recover. In the meantime we will bring forward planned operational development to minimize loss of luminosity. Program for the next few days follows.
| Friday morning |
Octupole polarity/ SPS wire scanner repair |
| Friday afternoon |
Octupole polarity/ SPS wire scanner repair |
| Friday night |
Switch LHCb polarity - test ramp - if SPS vacuum OK |
| Saturday morning |
Test ramp for chromaticity measurements through the cycle till
~12:00 |
| Saturday afternoon |
New SPS optics (Q20) to LHC |
| Sat night |
New SPS optics (Q20) to LHC |
| Sunday morning |
High intensity tests with normal setup |
| Sunday afternoon |
Transverse damper tune measurement tests |
| Sunday night |
Physics |
| Monday |
Switch ALICE polarity - 24 hour program (injection, tertiary collimators through the cycle, loss maps) |
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Date
|
Summary
|
Link to report from morning meeting
|
|
Mon 13 Aug |
- 00:00 Stable beams Fill #2927, intial lumi's 6.85e33
cm-2s-1
- Beams dumped by an interlock on TCTs in point 1.
Integrated lumi 152 pb-1
|
8:30 meeting |
|
Sun 12 Aug |
- 07:05 Ramp 2 x 2 x 144 bunches, injected with Q20
optics: all fine
- 07:51 Dump fill #2950
- BPMS interlock during injection
- 12:33 Ramp with 2 x 1374 bunches, 1.55e11 ppb, stability
checks
- 17:01 Dump beam
- 17:55 Injecting for ADT tune measurement test
- 19:37 Ramp for ADT
- 21:26 Dump ADT fill
- 23:12 Ramp for physics fill #2957
|
9:00 meeting |
|
Sat 11 Aug |
- 01:30 SPS kickers conditioned and ok but PS 40 MHz
cavity down
- 03:37 Injecting probes n05:24 Ramp with LHCb polarity
switched to negative, CMS solenoid off
- 07:00 Optimising collisions
- 08:35 Beams dumped, LHCb dipole tripped
- 10:34 Start test ramp for chromaticity measurements.
- 11:33 Beams dumped, prepare for SPS Q20 injection into
the LHC.
|
9:00 meeting |
|
Fri 10 Aug |
- 08:20 Beams dump. CMS solenoid emergency ramp down due
to cryogenics problems.
Integrated lumi 133 pb-1.
- 10:15 Octupole polarity measurements with beam.
SPS wire scanner exchange in parallel
- 19:58 End of measurements, beams dumped
|
8:30 meeting |
|
Thu 9 Aug |
- 01:48 Beams dumped. RB energy check went false, SMP
energy glitch? Integrated lumi 94 pb-1
- 05:35 Stable beams Fill #2932. Initial lumis 6.5e33
cm-2s-1
- 11:52 Beams dumped, SIS triggered following network
issue in CCR. Int. lumi 103 pb-1.
Going for access, while SPS is still down for EDF
intervention.
- 12:30 Access
- 16:30 Start pre-cycle
- 20:23 Fill #2933 dumped. Losses end of squeeze and
adjust. Vertical tune B2 hits third order resonance. Lower
tune for next fill.
- 23:25 Stable beams #2934. Initial lumi 6.5e33 cm-2s-1
|
8:30
meeting
|
|
Wed 8 Aug |
- 01:25 Stable Beams fill #2927, 1374 bunches (vertical instability end
of squeeze)
- 09:31 Operator dump.Int. lumi 103 pb-1
- 12:10 Stable beam fill #2928, still vertical instability end of
squeeze. Initial lumi 6.2e33 cm-2s-1
- 14:28 Beams dumped by QPS trigger on RQSX3.R1. Probably SEU. Int. lum
45 pb-1.
- 20:03 Stable Beams Fill #2929. Init lumi 6.3e33 cm-2s-1, still some
instability squeeze B2V at ~1.5 m beta star, but starts to look better.
|
8:30 meeting |
|
Tue 7 Aug |
- 00:24 Operator dump. Integrated lumi around 68 pb-1.
- 02:41 Fill #2919. Beams unstable throughout the squeeze.
Lost on HV BLM
- 05:05 Fill #2920 Stable Beams. Lumi’s around 6.3e33
cm-2s-1 (!), although some losses in squeeze.
- 06:20 Dump due to ALICE BCM. UFO…
- 08:10 Fill #2921 Dumped at start of ramp. Beam losses on
TDI IP8 which got stuck when moving out after injection,
resulting in a large angle.
- Switch octupole polarity: 450 GeV tests; test ramps - pilot, 12b;
- 21:21 Stable beams fill #2926 480 b
- 22:48 Operator dump
|
8:30
meeting |
|
Mon 6 Aug |
- 01:53 start injecting fill 2915, average bunch intensity
1.53E11, good ramp and squeeze
- 03:13 dump on instability 70 sec after the collision beam
process was launched due to RS9 losses on TCTH.4R5.B2
- 03:52 changing the thyristor did not solve the problem
with the ALICE solenoid à is staying off
- 04:20 SPS extraction kicker problem
- access in the mean time. ALICE solenoid fixed.
- 13:00 Pre-cycle by running nominal
ramp with reduced octupole currents in the ramp.
- 15:00 Injecting physics beams fill
#2917.
- 16:21 With squeeze finished beams
dumped due to ALICE interlock. ALICE BCM dumped with values
300 % of threshold. Expect UFO.
- 17:48 Injecting for physics, fill
#2918
- 19:07 Stable beams. Low initial
lumi's of 4.5e33 cm-2s-1 due to blow-up of bunches end of
ramp with octupoles at 150 A.
|
8:30 meeting |