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Wednesday 13 th February - last 24 hours. 07:41 Programmed dump of fill 3556 (510 bunches) after 5h 26min 09:01 Start injection of fill 3557 (1347 bunches) 10:30 Stable beams, initial lumi ~90E30 11:32 Beam dump BLM spurious trigger on a BLM optical board in R1
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Wednesday 13th February - last 24 hours • 07:41 Programmed dump of fill 3556 (510 bunches) after 5h 26min • 09:01 Start injection of fill 3557 (1347 bunches) • 10:30 Stable beams, initial lumi ~90E30 • 11:32 Beam dump • BLM spurious trigger on a BLM optical board in R1 • 14:07 Stable beams fill 3558, initial lumi above 100E30 • 15:15 Beam dump • RF fault • 16:25 LHC in access mode (RF + MQK) • 20:25 Patrol started in PM45 (lost during access) • 21:39 Ready for injection • dump test for XPOC data collection test • 22:40 Stable beams fill 3559 – initial lumi ~120E30 • 07:00 Beams dumped by OP • ~2 pb-1 in 8h30m Thanks to MatteoSolfaroli for the slides! LHC status
Total integrated luminosity at 1.38 TeV 3556(500b) 3559 3558 3557 ATLAS total now ~3.5 pb-1 LHC status
Last 24 hours 3557 3558 3559 Abort gap high cleaning effect LHC status
Fill 3557 Intensity ~ 1.2E11 p/bunch Injection B1 then B2 Big losses on B1 at start of collisions Peak lumi ~95E30 Improvement on lifetime (~5h) when trimming the octupoles down from 3.0 to 2.6 units in collisions LHC status
Fill 3557 Strong excitation visible on B1 and B2 around 0.29 (8 kHz line?) which becomes more pronounced when going into collision. The line is visible already before and seems to be most pronounced in the vertical plane. B1H B1V 0.29 0.29 B2H B2V 0.29 0.29 LHC status
Fill 3558 Lifetime dip and losses improvedchanges wrt previous fill • Some time spent at flat-top to wait for the tunes to stabilise • Alternating injection B1 and B2 • Reduced landau octupoles strength on the second part of the collision BP from 3 to 2.6 (~120 A to 100A) Peak lumi ~140E30 LHC status
Fill 3558 - dump • At 15:15 beam dump due to trip of RF module M1B1 Alarms on RF: ACSModuleM1B1 : Crowbar Grid current (LV side) out of range. Else HV-RF specialist intervention required to check and in case replace crowbar. ACSLine4B1: Main HV Power not at Nominal • ACSLine1B1: Main HV Power not at NominalACSLine3B1: Main HV Power not at NominalACSLine2B1: Main HV Power not at Nominal-> The power converter is not delivering a minimal nominal voltage (set to 40kV). Power converter off or wrong voltage output. Measurement system faulty. Check power converter settings and acquisition with expert interface. In case call power converter piquet or access required. LHC status
Access – Tuesday evening • Access was given to RF zone to fix the fault on M1B1 • In parallel access for the MQK – a test was performed to check the MKQ functionality • During the access the patrol on PM45 sector 1 was lost – had to be redone LHC status
Fill 3559 Peak lumi~155E30 Octupoles strength further lowered while in stable beams down to 1 unit, then trimmed back to 1.2 Bigimprovement on lifetime Octupoles to 2 units Octupoles to 1.2 units Abort gap cleaning ON AGC had to be switched ON continuously during the fill LHC status
Plans • Refill for physics • (beam unavailable from Booster this morning for 4 hours) • This afternoon – VdM – INDIVs • Plus loss map • Operational development • Fill overnight to finish – RPs in to 13 sigma • 06:00 Thursday – start quench test program • No ions LHC status
Roman pots - request Mario Deile • At the end of the upcoming 1400 bunch fill we briefly insert the pots to the validated position of 22 sigma, just as a necessary condition for proceeding further in the plan. I remind that last night's insertion to • 22 sigma from the 500 bunch fill was without any problem. • At the end of a low-intensity fill, possibly the VdM fill, we insert the pots to 13 sigma (where we would have physics acceptance) and do a quick loss map at dumping time. • If this loss map is ok, we insert to 13 sigma in the remaining fills. LHC status
Accesses • Accesses for quench test: • Scope installation in IP6 (12L6). 2 hours. It has priority over Q6L8 scope installation • Fast measurement system on RQ6.L8 (30 min in the UA83 by Jaromir Ludwig). Ramp to 300 A afterwards. • Access for circuit tests – in the shadow • Change hardware limits on all Individual Powered Quads • EPC, 2 hours during working hours LHC status