In summary, stable beams were declared 30 minutes ago, but the initial collision rate is low, at only 0.2% of the design rate. This is because the machine operators must ensure safety and check for any potential dangers before filling in more protons. It will likely take a few weeks to reach the same collision rates as last year. Meanwhile, experiments are starting to collect initial data, and the low collision rate of 0.2% is actually ideal for certain analyses. However, at design values, this means that 99.9975% of collisions are discarded due to limitations in data processing. The beam dump, which is a block 70 cm x 70 cm x 7 meters in size and surrounded by
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The 2017 run has ended this morning and the machine is being shutdown.
Sector 1-2, which had the 16L2 problem, has been warmed up partially. It is expected that nearly all of the gas in it is gone now.
For 2018, 138 days of proton-proton running are planned (compared to 127 in 2017), with an expected luminosity of 60/fb for ATLAS and CMS.
It is expected that both ATLAS and CMS will want to keep pileup at about 60 interactions per bunch crossing. Without the 16L2 issue we get up to 2544 colliding bunches, or 2.15*1034/(cm2*s) luminosity, 215% the design value. If that works well and the experiments are happy with more pileup, the machine operators have some ideas how they could possibly go to 250% to 280% the design value. Such a high initial luminosity makes faster re-filling more interesting for ATLAS/CMS. LHCb mainly wants long fills and is not interested in these high luminosity values, so some compromise has to be found.
With 2018 data-taking probably. I don't expect so many events in 2018, however. Unless something unexpected comes up the focus will be on doing more of the same to get as many collisions as possible before the longer shutdown.
SuperKEKB/Belle II are expected to start data-taking in 2018, that will be new.
