by Chris Baker
Conseil Europeen pour la Recherche Nucleaire or CERN to be brief is the Mecca of physical sciences and it has been my pleasure as an interested chemist to escort hundreds of physics and science teachers on this pilgrimage. (by the way they try to play down the “Nucleaire” bit – something about the public associating the word nuclear with very bad things ). So, what is it like?
Well on the surface it is a bit like a cross between a university campus and a light industrial estate, spread-eagled across the Swiss/French border.
Large Hadron Collider courtesy of CERN
You can choose to eat in Restaurant 1 which is in Switzerland or Restaurant 2 which is in France and somewhere in between you can straddle the border if the mood takes you. You may wonder why I mentioned restaurants? Well it is in these restaurants where staff dine on refectory style tables where much scientific discussion goes on. Teachers have reported exciting conversations with scientists they sat next to at lunch although no one has claimed to have spoken to a Noble Prize Winner to date – but give it time. CERN prides itself on its openness and there is no restriction on taking photographs.
I will get on to the LHC (large Hadron Collider) later, but first it is worth remembering that CERN is not just world class in particle accelerators. It was where Tim Burners-Lee, a scientist at CERN, invented the World Wide Web as a means of sharing information for scientists around the world. You can visit Tim’s old office – an unassuming room in a dingy corridor now resplendent with brass plaque recording the historic event, and yes, you can get your photograph taken next to it! This helps to get across the message that CERN is a collaborative venture of scientists spread across the world who may work full time in Geneva or just visit to do occasional research and experiments.
CERN teachers’ programme
The teachers’ programme is mixed and varied. There is a practical activity – making a cloud chamber using aquarium tanks which one teacher improved on tremendously with an ingenious design using cheap seed propagators and and LED rope light. There are lectures which focus on academic particle physics – useful for teachers who are a little rusty in this area and great for snippets to teach how science works.
Rolf Lander, antimatter scientist and Head of Education at CERN, explains how historically models were developed and become accepted until someone disproves the model and new models are put forward. We had a good example of HSW (how science works) recently when the scientists in CERN found unusual results when they timed how long it took for neutrinos to travel from CERN to Italy. They appeared to travel faster than the speed of light and this made headlines in TV News and newspapers around the world. CERN scientists invited other scientists to investigate and try to replicate their data. The invitation did not last too long as CERN scientists discovered the reason for these anomalous results – a loose wire! Strangely this did not make the news to such an extent.
In the lecture on Medical Physics. Manjit Dosnajh helped to answer a key question that many people have about CERN i.e. what tangible benefits do taxpayers get from funding all these scientists. Manjit illustrated how work on Positron Emission Tomography (PET) carried out at CERN in 1977 led to hospital imagers which now run alongside CT and MRI scanners (often in combination) to provide information to treat cancers. A specialised version of a PET scanner has been developed which can detect small tumours missed by other scanners. This has proved very successful in the detection of breast cancers – and using the same technology as the LHC. This shows that technology developed at CERN is in use in our hospitals to increase survival rates from life threatening conditions
Physics in the movies
Rolf Lander provides an excellent lecture on the physics behind the film Angels and Demons. In the film 1g of antimatter is stolen from a laboratory in CERN and the plan is to use this to blow up the Vatican. In an entertaining lecture Rolf explains the physics behind the film and if it is really possible to create 0.5g of antimatter (enough to make a powerful bomb), just how long and how much electricity it would theoretically take. The cost by the way is: 1,000,000,000,000,000 euros with a delivery time of 1,000,000,000 years. Great stuff for teachers who can now legitimately intersperse physics lessons with clips from the Angels and Demons film. For the antimatter enthusiasts, CERN have produced a teaching module on antimatter.
The hunt for the Higgs Bosun
Data from CMS. courtesy of CERN
The highlight of the programme is a visit to CMS – Compact Muon Solonoid. CMS is just one of the LHC experiments but it was CMS that confirmed the existence of the Higgs Boson in 2012 and it was enthralling to hear how this was done. When I got home my painter and decorator asked about my last visit. He had heard of the Higgs Boson and was interested. “Can you see it?” he asked. Several cups of tea later I had managed to explain that the Higgs Boson was detected by analysing signals and that the detection instruments took the equivalent of 4,000 pictures a second. He was still none the wiser and it really brought home to me that to teach particle physics successfully, it helps if you have a physics background but more importantly that you have the models, analogies and experiences which enable you to help students with the associated complex abstract thinking. This is one of the greatest benefits of a visit to CERN.
So the highlight for the teachers was CMS or maybe it was the magnet testing facility where you can stand next to some of the biggest electromagnets in the world. When fully operational over 21,000 amps flow through five huge coils to produce a magnetic field of between 4 and 8 tesla. One teacher proudly demonstrated a magnetic field detecting app on his iphone. He planned to use this in the magnetic testing area. We were expecting a fried iphone but he reported it worked really well!
The magnet testing facility also houses a mock up of the particle accelerator tunnel. This is very useful as access to the tunnel during operations is forbidden for obvious reasons. The tunnel is roughly the width and height of a poly-tunnel greenhouse with enough room to ride a bike along the side which is the primary mode of transport (when not operational!).
CERN programme highlights
The highlights of the CERN programme for me did not come from CERN but from the follow up day at the National Science Learning Centre in York. The programme has some interesting inputs on nuclear fusion amongst others, but the real stars were the teachers and what they did with the ideas, materials and experiences picked up at CERN. They were “fired up” by their visit and the enthusiasm of the CERN scientists and had completed a myriad of activities and projects. Many of them had gone on to arrange a CERN visit for their students. Others had woven anecdotes, models and analogies into theoretical topics. Some had run whole school assemblies on CERN and some showed pictures of their students and projects in their local newspaper.
If you have not made your pilgrimage to CERN, 2013 could be a good year to start.
The National Science Learning Centre is running a study visit to CERN in February 2013.
If you have already been to CERN we’d love to hear your thoughts and experiences of the trip as well as how you have applied it back into the classroom.
Filed under: chemistry teaching, Contemporary Science, Materials Science, physics teaching, Secondary and Post-16, triple science | Tagged: CERN visit, continuing professional development, Higgs Bosun, particle physics, Physics, Physics in the movies, Science Learning Centres, teacher programme | 2 Comments »