1. The problem statement, all variables and given/known data The circumference of the collider is 26.66 km, and there are 4 equally spaced points where the beams collide. A collision takes place every 22microseconds at each one of the collision points, with 4 bunches in each beam. The average current per beam is 3mA. I have to work out how many particles per bunch this corresponds to? I've looked everywhere for a relevant equation and can't find anything! Any ideas please?