Page   03     of 25

Detector Shapes

Physicists are curious about the events that occur during and after a particle's collision. For this reason, they place detectors in the regions which will be showered with particles following an event. Detectors are built in different ways according to the type of collision they analyize.

Fixed Target: With a fixed-target experiment the particles produced generally fly in the forward direction, so detectors are somewhat cone shaped and are placed "downstream" from the collision.

However, modern high energy detectors like Atlas use colliding beams and are somewhat cylindrically shaped.

Colliding Beams (Atlas detector): During a colliding-beam experiment, the particles radiate in all directions, so the detector is spherical or, more commonly, cylindrical.