Liverpool scientists trap antimatter at ALPHA experiment

Physicists at the Universities of Liverpool and Swansea have succeeded in trapping atoms of antimatter for more than 16 minutes, long enough to begin to study their properties in detail. Antimatter was trapped using an experiment called ALPHA, part of a broad programme at CERN's (link to: http://public.web.cern.ch/public/) antiproton decelerator investigating the mysteries of one of nature's most elusive substances. ALPHA uses a silicon vertex detector which was designed, commissioned, and built in the Liverpool Semiconductor Detector Centre. Particles that are known to exist in the Universe have their mirror image in anti-matter, but with the opposite electrical charge. It is thought that when the Universe formed, matter and anti-matter existed in equal measure, until they collided and annihilated, with the residual matter making up the planets of the solar system. Although anti-matter is known to exist - in the stars for example - scientists have questioned for many years why it is only matter that can be seen in our physical world today. Professor Paul Nolan from the Department of Physics (link to: http://www.liv.ac.uk/physics/ ), who leads the Liverpool team, said: 'Our aim is to study antihydrogen, and make detailed comparisons with ordinary hydrogen.