1. LHC status Wednesday 15 th July 2015 Coordination: Wolfgang Hofle, Mike Lamont

2. Tuesday 14 th July 08:19 Fill 3996: Ramp started (4 th ramp with 476 bunches), trip of RCO, RCD A78 before reaching flat-top 09:13 Stable beams, initial lumi 1.7x10 33 cm -2 s -2 – Record peak lumi, blow-up just under control at 450 GeV with Scrubbing recipe: 0.2 ADT gain, Chroma 10, octupoles -1.5 12:07 IP 1/5 optimization and separation in CMS to reduce lumi as requested, down to 70 then 50 (55  m separation in separation plane) 13:14 dumped by QPS A.23 – Before abort gap cleaning tests could be done 15/07//2015 LHC Morning meeting – WH & JU 2

3. Tuesday 14 th July 17:20 Getting ready for injection, plan: change back octupoles to -0.5 to disentangle influence of ADT gain, chroma and octupoles on blow-up (need to know in anticipation of next intensity step) 17:52 RF module M1B1 tripped due to glitch on temperature reading (RF window), Piquet called, ok to continue 18:09 Probes in, IT Database error, cannot control anything 18:51 Injection can continue 6 bunches ok, no blow-up 15/07//2015 LHC Morning meeting – WH & JU 3

4. IT-DB Issue IT-DB Administrators performed a supposedly "background" maintenance operation on some audit data on the ACCCON database cluster (hosting InCA/LSA, CCS, Logbooks, AFT) in order to recover the storage. This operation lasted ~10 minutes, and caused all sessions to queue - waiting for the operation to complete. IT-DB had previously performed this operation on other databases without any impact on the corresponding services. They will follow-up this procedure with Oracle to understand why it was not in the background as expected for this case. LHC did not lose the beam, but they did lose the means to control it. Other accelerator controls were also affected. Once the database maintenance operation completed, things receoved by themselves, with the exception of the ELogbook Web interface, and RBAC logins. Alastair restarted the Elogbook server, and Wojtek Sliwinski restarted the RBAC servers. Chris Roderick (called by L. Ponce for OP-LHC). 15/07//2015 LHC Morning meeting – WH & JU 4

5. Instabilities @450 GeV Scrubbing recipe: – ADT gain to 0.2 – octupoles to -1.5 – chromaticity to 10 Beam 2 octupoles back to - 0.5  horizontal blow-up first of parts of the trains, then vertical blow-up Beam 1 chromaticity to 5 units  blow-up vertical first, then some horizontal blow-up Continued with scrubbing recipe Injection cleaning test  no adverse effect seen on emittances (triggered by sending request w/o injecting beam) Injection oscillation on ADT ok, blow-up shortly after injection 15/07//2015 LHC Morning meeting – WH & JU 5

6. Instability check at 450 GeV 15/07//2015 LHC Morning meeting – WH & JU 6 Octupoles: -0.5 Chroma: 10 ADT: 0.2 Octupoles: -1.5 Chroma: 5 ADT: 0.2 Back to scrubbing settings: -1.5 / 10 / 0.2

7. Ramp Fill 4000, 14 th July Delayed filling due to Injection oscillation missing on IQC – Expert called for verification (Guillaume) – Also FBCTC-B2 measuring too low beam current; reboot cfv-ua47-bctfra ok On top: – SPS BQM stopping beam + PS RF cavity issue – BPM crate in point 5: issue is back (no data), c.f. crate was already changed 15/07//2015 LHC Morning meeting – WH & JU 7

8. No Injection Oscillations in IQC 15/07//2015 LHC Morning meeting – WH & JU 8 Needs experts: BE-BI to investigate urgently: w/o compensatory measure (t.b.d.). This is a potential blocking issue; appears for 2x36 bunches, but 36 and IND, probe ok ADT shows damped injection oscillations for the trains (1 st bunch)

9. Ramp Fill 4000, 14 th July Delayed filling due to Injection oscillation missing on IQC – BI Expert called for verification (Guillaume Baud) – Also FBCTC-B2 measuring too low beam current; after reboot cfv-ua47-bctfra ok On top: – SPS BQM stopping beam + PS RF cavity issue – BPM crate in point 5: issue is back (no data), c.f. crate was already changed 23:12 Ramp started 23:19 dumped by UFO 15R8 at 2.0 TeV 23:34 RCO.A78.B1 (2 nd time), V_out overvoltage on PC; EPC called 00:21 Cryo back (S81 quench recovery) 15/07//2015 LHC Morning meeting – WH & JU 9

10. UFO 15R8 15/07//2015 LHC Morning meeting – WH & JU 10 Quench of B15R8, dumped by BLMs

11. Fill 4001, 15 th July 2:23 injection started (476 b) – Confirmed IQC injection oscillations missing only with 2x36 bunches; verified oscillations damped using ADT displays – Losses at TDI < 50% (highest when probe kicked out) – Beam quality with “scrubbing recipe” marginally under control 15/07//2015 LHC Morning meeting – WH & JU 11 ADT vertical Beam 1 Inj oscillation ADT vertical Beam 2 Inj oscillation

12. Fill 4001 BSRT Emittances 15/07//2015 LHC Morning meeting – WH & JU 12 (Just) under control at 450 GeV using the “Scrubbing recipe”

13. Fill 4001, 15 th July 3:11 ramp started 3:18 QFB off beam 2, no RT values sent (after the fill reboot of crate) 3:54 colliding 4:06 stable beams 4:07 dumped by QPS B11.L1 (SEU) Preparing for injection: – Wire scanner B1-H: reset by Ana G. – QFB: process BOBIDT_B_DU_M restarted – BLM sanity checks (need to run them more than once) 5:52 pre-cycle started (after longer wait for dump resistors cool down) 15/07//2015 LHC Morning meeting – WH & JU 13

14. Overview 14 th July 2015 15/07//2015 LHC Morning meeting – WH & JU 14 3996 476 b QPS 4000 476 b UFO 4001 476 b QPS

15. Fill Summary with 476 bunches 15/07//2015 LHC Morning meeting – WH & JU 15 FillStable beamsbunchesPeak Lumi 10 33 cm -2 s -1 Int Lumi pb -1 dumped by 39925.304761.42 22.16QPS RB.A81 399404760 0UFO 10L3 399504760 0UFO with quench, 34L8 39964.014761.7 20.23QPS trip RB.A23 400004760 0UFO with quench, 15R8 ! 400169”4761.6 <0.1QPS B11.L1 100 pb -1

16. Issues UFOs (15R8 also back), two quenches QPS trips (SEU) IQC: BPM injection oscillation: no data 2x36  expert investigation needs to continue BPM crate Point 5 continues to give problems RCO67.B2, RCD …reduction of current to be looked at, circuits taken out BLM losses high around triplet when going into collision – Increase BLM monitor factor done; TCTs; TCLs would have reach 100 % soon; Master Threshold to be considered for change at TCT R8 BQM publishing zeros close to injection, being followed up in RF (pending) 50 Hz lines in horizontal BBQ spectrum, remedies being investigated QPS: Four boards may need intervention in tunnel, wait for longer stop ? 15/07//2015 LHC Morning meeting – WH & JU 16

17. On the list Abort Gap Cleaning at 6.5 TeV  Wednesday – Test during the fill – eventually aim for automatic cleaning start triggered by abort gap monitor Vacuum info for XPOC (new release) dry dumps required Doublet tests as preparation for scrubbing (E. Calvo prepared procedure); need reaction time before scrubbing run usage of doublet beam MKI waveform beam 2, AGK check Tests of direct of BLM to Beam dump (during 25 ns ramp-up) Optimization of injection gap cleaning ADT high bandwidth settings in squeeze, collide; restore 2012 scheme, but no instabilities yet observed with current scheme ADT complete gain measurements, increase gain (optional when required) 15/07//2015 LHC Morning meeting – WH & JU 17

18. Accesses BI (Marek) UJ14, UJ16 & point 4 (BBQ, vertical beam 1 S/N) Alice, CMS (2h during working time), LHCb (2h) RF UX45 (installation of observation box before MD period) daytime 1h Collimators IP7, 1h QPS, when access ? 15/07//2015 LHC Morning meeting – WH & JU 18

19. Present planning (t.b.c.) 15/07//2015 LHC Morning meeting – WH & JU 19 LHCb requests polarity change shifted from Wednesday to Thursday  50ns_476b_414_32_397_72bpi10inj Back-up: 50ns_476b_426_32_392_36bpi16injp