The LHC in 60 seconds
Evelyn Thomson
Assistant Professor of Physics
The large hadron collider is a racetrack 16 miles around
for billions of protons moving at close to the speed of light. Round
and round the track the protons go, running 7352 marathons a second.
Two beams of such protons move in opposite directions around the track
and collide 32 millions times each second. Most collisions are glancing
and do little. A few collisions are head-on and convert energy to mass
in spectacular fashion by making exotic and massive particles that are truly the
universe's best kept secrets, having been hidden from view for 14
billion years since the Big Bang.
These exotic particles last only for a trillionth of a trillionth of a second,
then the fireworks from their decay rocket through giant detectors and light up
some of their 100 million channels of equipment made of silicon, xenon, liquid
argon, and lead. These detectors are the strictest of judges, auditioning 32
million proton collisions each second and selecting only the 200 most
interesting candidates, recording 30 audio CDs worth of information every
minute about those proton collisions for later review by scientists like me.