What's Up With Antimatter?

8th February 2018
Peter Knapp leading a tour

Back to work at CERN this week. The whole collaboration came together from all over the world for three days of discussion about what has happened over 2017 and the plans for next year. The construction of ALPHA-g (a device that will determine how antimatter falls in gravity) will call for ‘all hands on deck’ over the coming months as a space is cleared and the experiment is constructed. It will be wedged in the middle of the existing ALPHA apparatus, requiring one end to be rolled out by 4 metres to leave a space for the vertical atom trap to be installed. It will stand around 3 metres high and make our already-busy experiment even busier; it’s starting to feel a bit like the Industrial Zone in Sonic the Hedgehog.

You can still be a tourist working in a place as large as CERN. The LHC’s experiments are now open for tourists, although you have to book a place on a tour to go down. I took my video camera and spent the 15 minutes in the cavern interviewing a PhD student. When I was looking for videos on YouTube before I came to work at CERN there was very little out there about people like me; always experts in the field or presenters wowing things up. I wanted find out what life is really like for a research student at CERN, and this is a series I plan to make. Hopefully there will be about six interviews from researchers at a few varied experiments at the site.


My main ALPHA-g job this week is to make five aluminium boxes containing electronics to power five cameras that can image plasmas. The tasks include designing metal parts in software and sending the designs to a private company to make them, soldering and screwing the parts, and testing the components before they are fitted. More specifically, the camera is actually merely the imaging part of the apparatus, and the device that requires the power (with up to 5000 volts) are called MCPs (Micro-Channel Plates) that convert plasmas into electrons as they hit small channels of metal. These electrons then shower away and hit the channel again, liberating a few more. The high voltage is required to accelerate the electrons and give them enough energy to knock more off when they strike the metal again. This multiplying effect allows a small signal to be amplified and, once the electrons are converted into photons by a phosphor plate, allows a camera to image the size and number of particles hitting it. This is useful to know because only with this information can we change things around to improve the number of antihydrogen atoms made.

Since being back I have given a tour of the Antimatter Factory to a group of STEM (Science, Technology, Engineering, and Maths) Inspiration Award winners and three school talks. Over the coming weekend I will give a further three tours of the experiment to CERN alumni. It may seem like a lot, and all of it is unpaid, being a Master’s student, but this scientific world is just so interesting that it is a dream to tap into people’s curiosities and explain what unimaginable technology and science is at work here. I just have to find more time to earn money to pay the rent...