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They are starting on the 136 bunch fill now. This is an amazing rate of progress.

pcatom, thanks. I understand that they will increase bunch numbers as 32,64,104,152,200. Will they go all the way with 8 bunch injections or switch to 24 bunch injection at some point? If the current smooth running continues they should easily make it to 200 before the next technical stop on 28th Ma...

RocketManKSC, nice analysis although your extrapolation of the luminosity decay seems pessimistic. It should decay exponentially (perhaps faster at the start) The luminosity half life is about 15 hours. Theoretically the optimum runtime would be roughly 2 x sqrt(L*T) where L is the lifetime and T is...

tomey36, that question was answered by pcatom about 10 posts back in this thread.

64 bunches now circulating, preparing to ramp

They have been running with 32 bunches for peak luminosities of 33/ub/s. Already about 1/pb has been collected to add to the 40/pb from last year

They managed a turnround of only 2.5 hours between runs, much better than last year.

Objective for the week is 100+ bunches.

Multi bunch injections yesterday looked very smooth. The coordination page indicates that they will start running with stable beams and increasing bunch numbers from Wednesday. Everything is following the planned schedule nicely. Yesterday I was watching live events from CMS but the muon trackers we...

Todays morning report indicates that they are waiting on a decision to start stable beams. The collimator and beam dump have to give the all clear. http://lhc-commissioning.web.cern.ch/lhc-commissioning/news-2011/presentations/week10/2011.13.03-830meeting.pptx If we see stable beams today it may be ...

This is copied from the CERN bulletin at http://cdsweb.cern.ch/record/1335119 LHC Report: Towards stable beams and collisions Over the past two weeks, the LHC re-commissioning with beam has continued at a brisk pace. The first collisions of 2011 were produced on 2 March, with stable beams and collis...

@pcatom, thanks for the explanations

Does anyone know what the "intermediate energy run" is and what it is for? They have planned it for a few days some time in April.

Fingers crossed for some test collisions during the present fill.

Over the weekend they succeeded in squeezing down to beta* of 1.5m . Remember last year they only went to 3.5m so this is a big step forward. It will at least double the luminosity. According to the Sunday morning meeting report there were some problems with changes in the crossing angle bump during...

According to the coordination page they have injection studies this afternoon and first circulating beams tomorrow (Sunday 20th Feb)

The cryogenics page now indicates green status for all sectors while the coordination page indicates hardware commissioning and machine checkout are in progress until 21st Feb when we expect first beams for 2011, oh it just changed to "Prepare LHC for beam" with more details for next week: http://op...

The latest Reuters summary is at http://www.reuters.com/article/2011/02/09/us-science-cern-idUSTRE7185AQ20110209 The plan is to stay at 3.5TeV during 2011. There is still a possibility to increase energy to 4TeV during 2012 if ongoing measurements indicate that it is safe. Otherwise higher energies ...