Question: how do you get particles to experiment with?

Steve Marsden answered on 17 Mar 2016:

We start of with hydrogen atoms, and we strip the orbiting electron from it. The remaining hydrogen ion consists of a single proton.

We fire them round in a circle repeatedly. Each time they come round, we give them another kick, adding a little more energy until they’re travelling close to the speed of light. The circle has a 27 km long circumference, and the protons go around it 11,000 times per second!

This is similar to standing outside of a revolving door and trying to spin it as quickly as possible. Each time a door comes past you can give it an extra push, and bit by bit it gets quicker and quicker.

Eventually we reach our maximum energy, at which point we collide the protons head on. Energy can be turned into mass, and mass into energy (with a small amount of mass equaling a huge amount of energy). In the collision, all the kinetic energy we gave the protons can be converted into new particles. Potentially particles that haven’t existed since a fraction of a second after the big bang.

It’s these new particles that we wish to study.