CMS off line control room.

July 15th, 2017
CMS off line control room.

A couple of views of the Compact Muon Solenoid (CMS) off line data control centre. This is used to analyse data just sfter it is obtained from the experiment. There is an identical control room at FERMILAB in the USA for the same purpose.

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LEIR

July 15th, 2017
LEIR

This is the Low Energy Ion Ring used to accelerate Pb 82+ ions a few weeks each year for the ALICE experiment on the LHC. It camecat a good time on the course, as LEIR is small enough to view it all from above. In the pictures, you can make out the bending magnets (these are always red), the focusing magnets (always blue) and the Radio Frequency cavities which do the accekerating (tall, grey boxes at the far side). The focusing magnets are needed as the slightly different paths of ions through the bending magnets causes the beam to diverge (called emmitance), so the focusing magnets squeeze the beam so it is narrow again. You can also see part of the ring in a silver jacket. This is called the Kicker Magnet. This separates a part of the beam at a narrow angle from the main beam as it travels around the ring. This small part of the beam then passes through a septum magnet (far side, red, blue, red magnets) to the left of RF cavities. This separates the kicked beam and sends it out of the hall at top left wher bit enters the Super Proton Synchrotron for more acceleration before entering the LHC.

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Nobel Prize winner

July 13th, 2017
Nobel Prize winner

A view of the main lecture theatre at CERN. This is the view taken from just behind where Peter Higgs sat as the discovery ofvhis particle was announced 5 years ago. You may just be able to make out a clock on the far wall? Yes, it is a Rolex.

Ok, this place is big

July 13th, 2017
Ok, this place is big

Ok, this is a copy of a splendid slidecfrom our presentation today on CERN engineering. This is a jcb being lowered down the hole to where one of the detectors was to be installed 100m below ground. On the right is one of the 15m magnets being lowered into the LHC.

Magnet Facility

July 13th, 2017
Magnet Facility

The penultimate site tour this afternoon, this time to the Magnet Facility. It is here where the superconducting magnets are developed. This can take anything up to 4 years to go from design, prototyping, testing and then manufacture. They are currently building a prototype magnet for an LHC upgrade due in two years time. This prototype will not be complete until christmas this year, after which it will need testing before they will build the four magnets they need. If they need larger numbers of magnets then industry will manufacture them.

Because the LHC is a circle, the beam tube inside each 15m long superconducting magnet needs to be slightly curved, by 9mm +/- 1 mm between each end. This is done by building the magnet in two halves, bending it on a jig, then measuring with a laser where  to weld. After this has been done, a set of co ordinates are sent to a computer opperated welding machine for the welding to commence.

I also include a photo of all the wiring at thevend of a magnet which joins onto the neighbouring magnet. It is one of these connections that failed just afterv turning on the lhc in 2008 and damaged 15 magnets when they warmed up too quickly.

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