LHC Wed 16 Sept 2015• Struggling with cryo o-night Tuesday - Wednesday• 07:11 Injecting again• 09:00 Dump on injection of train of 144 bunches, losses IP7• 10:07 Again

– Transverse damper investigations and reboot of ADT crates

• 11:00 Injectors problems, cryo needs a break …• 11:44 Beam Current Change Monitor dump upon injection (oscillations)• 12:30 Injecting again• 14:19 Stable beams, fill #4376, 1033 bunches, 144 bpi• 14:29 Dump due to UFO 19R4

LHC Morning meeting – SR & JU 117/09/2015

Last 24 hours

LHC Wed/Thur 16 Sept 2015• 14:30 After dump lost cryo in 34, slow abort

– Full pre-cycle needed– Access for LHCb + …

• 17:30 Injecting again• 19:00 Problems PS during injection – dump as wait is long• 21:30 Injecting again• 22:30 During cryo wait very strong blow-up B2V: dump• 23:19 Dump lost CM in arc 34, followed by pre-cycle• 01:10 Injecting again, fill in 3 steps

– Chroma only down in V at waits

• 03:44 Stable beams fill #4381 1033 bunches, 144 bpi• Cross fingers (04:53 UFO at 65 %)

LHC Morning meeting – SR & JU 217/09/2015

Transverse Damper Problem

• Daniel called, the injection gap cleaning FESA class has crashed, so it could be related to that – he's talking to Anthony.

• It seems the problem is related to a, yet unidentified, stability issues on ALLADTmDSPU processes. The quickfix that we can apply is a reboot from Diamon of the 4 ADT crates

• We will investigate on how to improve situation in the coming days, in between this methods should be applied as soon as you receive too many "RDA exceptions" on TRANSVERSE DAMPER CONTROL application.

LHC Morning meeting – SR & JU 317/09/2015

Anthony

Fill #4376, 1033 bunches, 144 bpi

• 10 min stable beams• UFO 19R4

LHC Morning meeting – SR & JU 417/09/2015

Fill 4379: Dump after cryo wait

• Strong blow-up B2H but especially V• restart, next time only chroma down

vertically during wait: OK

LHC Morning meeting – SR & JU 517/09/2015

Fill #4381• Emittances at start of fill

• Some abort gap cleaning. Seems captured.

LHC Morning meeting – SR & JU 617/09/2015

The Plan• At least two good fills with 1033 b, 144bpi• Then possible step-up another 144 bunches

– This would reach another rMPP milestone

• Under discussion, special fill for ATLAS for next week: – 25ns_893b_881_828_830_72bpi17inj

any scans etc. well defined

• Parasitic– RF studies as end of fill– TCL scans for Roman Pots– Monitoring of triplet movements and effect on orbit

LHC Morning meeting – SR & JU 715/09/2015