The reason that detectors are divided into many components is that each
component tests for a special set of particle properties.
These components are
stacked so that all particles will go through the different
layers sequentially. A
particle will not be evident until
it either interacts with the detector in a
measurable fashion, or decays into detectable particles.
The interaction of various particles with the different
components of a detector:
*Neutrinos are not shown on this chart because they
rarely interact with matter,
and can only be detected by missing matter and energy.
Just so you know, the pion
() is a charged
A few important things to note:
- Charged particles, like
are detected both in the tracking
chamber and the electromagnetic calorimeter.
- Neutral particles, like
are not detectable in the tracking chamber;
they are only evident when they interact with the detector.
Photons are detected by the electromagnetic calorimeter,
while neutrons are evidenced by the energy they deposit in the
- Each particle type has its own "signature" in the detector.
For example, if a physicist detects a particle
only in the electromagnetic calorimeter,
then he is fairly certain that he observed a photon.
An electron and a positron
were produced when a particle and its antiparticle
collided head-on, perpendicular to this screen.
What conservation law APPEARS to have been broken?
Number of Leptons?