I LHC finishes proton-proton collisions in 2018

[websterling]

Also, Long Shutdown 2 will follow the Pb-Pb collisions, so no more p-p collisions till May, 2021.

 

[dukwon]

Ion run is over. LS2 started about 2 hours ago.

 

[websterling]

This is the LHC Status Page 1 this morning- There is some humor in the comments.

 

[mfb]

From the point of view of the experiments (especially LHCb) the energy situation is a bit annoying. You want your Monte Carlo simulations to be realistic, which means they should be at the energy the accelerator will run. Probably 14 TeV, but if the magnets can't be trained enough we might end up with 13 TeV or maybe 13.5 TeV. Do you do 14 TeV simulations now and risk that they become less useful? Do you delay the production until the energy is fixed and have less time for proper phase 3 preparation? Something in between?

For searches for heavy new particles (->ATLAS, CMS) the upgrade to 14 TeV is quite useful, so it is worth trying it. I don't know how LHCb thinks about this - they mainly look for decays of lighter particles and their production rate doesn't go up that much with 14 TeV.

 

[dukwon]

We produce MC for physics analysis after the data has been taken and we know what the conditions were. There is some Run 3 MC (at 14 TeV) but it's for detector upgrade studies, not physics analysis.
Our 2017 MC productions are only just starting now

 

[mfb]

You still have to optimize the trigger and so on.

ATLAS and CMS use MC produced in advance extensively for searches - you get results faster that way. Ideally the analysis methods are essentially fixed once the data comes in and you just have to run it over data and do all the various cross checks.

 

[websterling]

Run 2 is over and Long Shutdown 2 has started. No collisions till Spring 2021.

As usual, CERN has a number of interesting summaries-

A successful conclusion to Run 2

LHC Report: Another run is over and LS2 has just begun…

Key plans for the next two years of the LHC

 

[mfb]

LHC experiments share highlights for 2018

Nothing revolutionary but still nice to see progress.