|Posted on February 18, 2015 at 7:15 PM|
Genuine excitement at the prospect of getting up at 03:00 is not something commonly felt by a bunch of 16-18 year olds. However, thirty Berkhamsted physicists felt exactly that when given the incentive of a visit to the largest science experiments in the world.
CERN (European Council for Nuclear Research) is focused on providing answers to fundamental questions about the early universe, how particles interact and the laws of nature that govern the world around us. They use purpose-built particle accelerators and detectors to drive beams of particles to very high energies until they are travelling close to the speed of light; once at this speed the beams are collided. Several tens of millions of collisions occur each second and the products and nature of each one of these collisions are detected. From this, a worldwide network of computers studies every one of these results. Any patterns or abnormalities are noted and can then be analysed by scientists either working at CERN itself or anywhere else in the world.
Amongst other interesting activities, we were lucky enough to travel underground to see the CMS (Compact Muon Solenoid) which is a detector at the LHC (Large Hadron Collider). It is built around a huge magnet and in total it is 21 metres long, 15 metres wide and 15 metres high - it was at this point that we realised the astonishing engineering and technology that goes into these experiments. Indeed, it was at CERN where the World Wide Web was founded due to a scientist not wanting to travel around the site to deliver messages and results to colleagues. Laziness truly is the mother of invention.
The CMS is focusing on a range of ideas from simply studying the standard model to searching for extra dimensions and particles that could make up dark matter. A recent publication from the CMS provides the broadest set of results about the properties of the Higgs boson (discovered at CERN on 4th July 2012). From looking at data taken between 2011 and 2012, the particle detected cannot be distinguished from the Standard Model predictions for the Higgs boson.
The Higgs boson decays (splits) into many different particles, including photons, Z bosons, W bosons, tau leptons, b quarks and muons. By looking at how the Higgs boson decays into these particles, and with what probabilities, physicists will be able to gain a better understanding of the Higgs boson. Finding no significant discrepancies with the Standard Model so far has set the bar high for when the LHC is turned back on (as it is currently having a makeover in order to make it more powerful and more effective). Theoretical and experimental physicists are still continuing to work together to find a small fault in the (so far) perfect picture of the Higgs boson. That small fault could lead the way out of the safe and familiar Standard Model theory and into the as-yet unknown physics beyond. It's going to be an exciting second run for the whole science community.
The feeling amongst the students on the trip was one of genuine awe. It was not the case that we were simply impressed by the large-scale engineering and seemingly beautiful (yes, beautiful) design of the detectors and accelerators. We were all truly struck by the wide range of discoveries and advances in science that CERN has facilitated; their mindset of sharing data and being an international research facility; and the way in which they are constantly evolving and progressing to work in a more efficient and powerful way.
Whatever happens when the LHC is turned back on, we can’t wait to find out.
Photo by by Emma Lewis