1. Programme for Saturday 10 July
Understand the RF problems affecting LHC
Filling for Physics fill with single10b_4_2_4_rot
EOF - ADT feedback
Injection studies
Physics fill with single9b_6_6_6

2. Saturday 10 July Morning: 8:00 -12:00
Filling for Physics fill with single10b_4_2_4_rot
Injected O.K. 10 bunches of beam 1 and 9 bunches of beam 2
On the request of the 10th bunch of beam 2: LHC-RF got de-synchronised – as last night.
Experts investigating. Meanwhile, RF noise on Beam 1 appeared again, creating beam 1 de-bunching (~1e10p in the abort gap). Total losses from the buckets: ~2.5 e11p
12:00 : dump beams (after cleaning some of the beam in the abort gap)

3. Saturday 10 July

4. Saturday 10 July
RF problems with single10b_4_2_4_rot on bucket number Philippe and Frederic
Request bucket number 29700
Processing of this value: an offset is added and then number cast in a short integer.
For value above there is an overflow and the most significant digit is disregarded resulting in a number which is too small for the bucket selector  common frequency generator is stopped.
SPS is locked on the LHC and without this common frequency it will not even take beam from the PS.
Fri-Sat night: SPS switched back to its local clock, and beam was re-established in the SPS.
LHC RF problem was then solved by sending manually a "NEXT INJECTION RF BUCKET“, which un-blocked the common frequency generator but … did not solve the problem.

5. Saturday 10 July Saturday morning :
Again we logically requested bucket number Same effects are observed  bucket selector stopped!
Had to switch off/on the synchro-crate which hosts this board in SR4
Dry test done with bucket 1  O.K. Test with bucket  same problem. And therefore investigated and understood the problem
DO NOT USE bucket number above 29626
Will be fixed on Monday (not needed in this fill)

6. Saturday 10 July B1 RF noise problems: Philippe and Frederic
While investigating, observed big de-bunching on beam 1 with signature similar to last Sunday  RF noise
The clock generator module in SR 4 produces the clock used by the RF demodulators. One of this clock (380 MHz) is produced by a Phase Lock Loop which was not locking anymore on beam 1, generating bursts of noise in the loop.
Re-tuned it to put it back in the middle of the range. The effects is not caused by temperature but probably humidity. To be monitored periodically.
The same module has been in operation in UX45 since Oct and showed small drift.

7. Saturday 10 July
13:30 : Refilling with the single9b_6_6_6, without this bucket number
At the end of injection  beam dump by an electrical glitch caught by the FMCM in IP6
14:30 : re-starting the injection, single9b_6_6_6.
18:30 : at 3.5 TeV, squeezed, right before collapsing the separation bumps, got hit by another electrical glitch on the network which was caught by the FMCM in Pt 1 and 5 and dumped the beams
18:30 : Ramp down combo
20:00 : Towards the end of ramp-down combo, got hit again by an electrical glitch which tripped S Later on, got hit again by cryo-maintain in S67 (spike in the pressure sensor)
20:00 – 22:00 : Pre-cycle sectors 67 and 78

8. Saturday 11 to Sunday 12 July
00:30 Injected 9+9 nominal bunches – TI 2 TL and protection device setting-up of Friday successful : IQC does not latched anymore for B1.
Ramped and started to squeeze. Orbit feedback was not on and the orbit drifted until the beams were dumped at 2:45 before getting to the 7 m stop point.
At about 4 am lost CM in 56 and 67 - this was quickly solved by the cryo piquet and operator so that at 6 am the conditions were already back.
4:15 - 8:00 : WorldFIP communication problem affecting cells 15R4 to 8R4: access in pt 4 – repeater changed.
Pre-cycling and preparing LHC for 450 GeV injection

9. Programme for Sunday 12 July
~11:00 – 23:00 : Injection studies pending readiness of the LINAC source (control problems)
Overnight : Physics fill

10. To Be Done
Establish absolute reference orbit with stable beam configuration – Joerg Wenninger
EOF:
ADT with colliding beams – Wolfgang Hofle
Octupoles to zero
WS (vs. BLM threshold, also during the ramp) – Bernd Dehning
Loss maps – Ralph Assmann
Beam time requests:
Hump measurements – Gianluigi – 450 GeV, 1.5h
Optics measurements – Rogelio Tomas, 450 GeV (8hr) and 3.5 TeV (8h)
Beam-beam studies – Werner Herr (few shifts)
High/Low gain sensitivity switch (mostly parasitically)
ADT: 450 GeV, 8 hrs, to check the noise improvement after going to the high intensity settings, complete the set-up of one missing pick-up

11. Pending Requests
FMCM : re-visit / tests whether the threshold can be relaxed?
Access requests:
Wire scanner B2: electronics board to change – Anna Guerrero
TCLA.B5L3.B2 collimator (during next TS) – Alessandro Masi
Check Clock Gen. in Faraday Cage (SR4) – Philippe Baudrenghien
In investigation:
RSS.A34B1 S34 : No PM by detector due to the low current level in the circuit --> no trigger. PM however from switch confirming self opening (both flags change state). 1st event of this kind in LHC to be studied by EE experts once back from holidays. But tripped again 2 other times