ATLAS

July 18th, 2017
ATLAS

The last of the site visits of this three week course. This was a very special one ascthis visit was only for the four people working with the International Particle Physics Outreach Group IPPOG. The lead for IPPOG is Steven Goldfarb from the University of Melbourne, Australia. He is responsible for outreach for the ATLAS experiment here and invited the four of us to witness an on-line virtual visit to ATLAS and CMS with some Physics teachers in the USA. The four of us being Suliman (Iran), Rob (USA), Katrin (Estonia) and I. Steven has set up a pop up tv studio next to the ATLAS Control Room.

Check out the photos, the mural painted on the wall is of the ATLAS detector and has a scale of 1:1, so is real size. Remember though, that this is also 100m below ground. Other views show the control room and update displays, as well as a view of Steven talking to teachers in the USA.

The rest of the week is now made of the final lectures and reporting the progress of the working groups. Somupdates may become scarce.

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Alunite at CERN

July 18th, 2017
Alunite at CERN

I met with Richard Catherall yesterday over lunch. Richard is an ex Alun School student who is now Technical Co- ordinator for Isolde. This is the experiment I paid a visit to towards the end of last week.

Richard came to the Alun from Bryn Coch primary school and left age 16 to take up an apprenticship at what is now Airbus in Broughton. Afterca few years here, he applied for a job advertised locally for a welder who could speak French and was happy to move out to Geneva. Having an O-Level in French, he decided to go for it. This is how Richard arrived here from Mold. 

He spent 7 years as a sheet metal worker and welder whilst at the same time completing a degree with the Open University. After this, he became a technian on Isolde, with responsibilities for building targets and ion sources. Eventually, Richard found himself promoted to Technical Co-Ordinator in 2005 for Isolde. He has 20-25 people working for him now, a mixture of CERN staff, students and post doctorate personnel.

He still visits Mold occasionally, so one day, we may all see Richard paying us a visit.

LINACS

July 15th, 2017
LINACS

We have been able to see inside an old Linear Accelerator Assembly today. These may be familiar to yearr 13 students. The beam passes down the centre axis where they are accelerated across the gaps between each tube. The polarity of the potential on the tubes is switched rapidly, so a positive ion is attracted towards the tube (negative voltage acceleration). Whilst the ion is in the tube, the polarity is switched to become positive, which pushes the ion out towards the neighbouring negative polarity tube (acceleration again). You may just be able to notice the tubes have increaesing lengths along the LINAC. This is because the beam travels further (faster) between each time the tube polorities are switched.

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Antihydrogen

July 15th, 2017
Antihydrogen

It is not yet known if antimatter behavescthe same as ordinary matter in a gravitational field. Will Newtons antiapple fall in the same way as an apple? Will it indeed fall at all. Here is a view of the Aegis experiment in the antimatter factory. Antihydrogen enters via the sloping pipe from the right, with a detector below if they fall. They can also perform spectroscopy on Antihydrogen here. If antimatter behaves the same as ordinary matter, then the spectral lines in both should be identical.

Antimatter

July 15th, 2017
Antimatter

Have spent a lot of time today considering antimatter. A lecture in the morning, ripping to pieces the bad science in Angels and Demons about antimatter, very entertaining. Then a visit in the afternoon to the Antimatter Factory. Here they donthings in reverse to everywherevelse at CERN, where they need to slow down the beam to very low kinetic energies (keV) to the antiprotons and positrons can be trapped to for antihydrogen. Because the experiments are in operation, it wasnt possible to see the decelerator ring, but you may just be able to make out its path around the Antimatter Factory, it is underneath the really big concrete blocks in the video. These are needed to shield the users from the radiation emitted by the circulating beam.

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