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4th July. Two physics fill during the day Smooth data taking LHC plans changed : 90m run postponed to tomorrow (24h) OT FE still excluded , to be looked at in more details today during the cryo intervention TPU TELL1 throttling. LHC. LHC LAST 24H AND PLANS (July 5)
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4thJuly • Twophysicsfillduring the day • Smooth data taking • LHC plans changed: 90m runpostponed to tomorrow (24h) • OT FE stillexcluded, to belookedat in more detailstodayduring the cryo intervention • TPU TELL1 throttling
LHC LHC LAST 24H AND PLANS (July 5) • - Wednesdaymorning - afternoon: Stable Beamsdeclared for fill 2806 with 1374 bunchesat 09:30, dumpedat 18:50. • - Wednesdayevening: Twoattempts to fill for physics in the eveninglostduring injection due to injection failureswithbuncheshitting straight the injection absorber. Bunchesarrived 50us tooearly due to SPS RF being on local clock. It is not understoodwhythiswas not caught by interlock, to beinvestigated. • - Wednesdayevening: Oilleakdiscovered on surface screwcryocompressorat point 2, intervention scheduled for Thursday morning for 4h. • - Wednesday night: Stable Beamsdeclaredwith 1374 bunchesatmidnight. Oilleak on screwcompressorworsened, and finallycompressorlostat 03:40. System reconfigured to survive withonly one screwcompressor, cryo conditions not lost, down in shadowwhilebeams in physics. Plan • - Attemptrepairingscrewcompressorat point 2 in the shadow of physicsfill, if the rewelddisturbesneighbouringequipmentcould lead to loss of cryo conditions and 12h recovery. If not, repairwouldbefinished by noonwith no loss of cryo and disturbance to beam. • - Keepcurrentfill. • - Refill for physicslatemorning-afternoondepending on success of compressorrepair. • 90m beta* setup starting Friday morning ~09:00 for 24h • - Resumephysics on Saturday morning
Fill2806 • Started9:00, ended18:48 • 1262collidingbunches, m=1.7, L=3.9x1032 • Record 12 pb-1, with94% efficiency • L0 raw rate: 937kHz • HLT Physics rate : 4kHz • Deferral23%, all deferredrunsprocessedafterfill. • Problems: • OT FE disabled • Somefarmnodesexcluded/included
Fill2807 • Startedmidnightongoing • 1262 collidingbunches, m=1.7, L=3.9x1032 • 11.7 pb-1recordedwith 95% efficiency • Problems: • OT FE desactivated • SomeFarmnodesexcluded/included • Manual reset of RICH to recoverdisabled HPD tooksome time to do