The electron and the muon have the same charge, but the muon is 200 times heavier than the electron. The bremsstrahlung emitted by all charge particles in interactions with electric or magnetic fields depends on the mass of the particle:
In limiting cases examined the total radiation goes as at least m^-
which accounts for why electrons lose energy to bremsstrahlung radiation much more rapidly than heavier charged particles (e.g., muons, protons, alpha particles)
This is utilized by constructing electromagnetic calorimeters which absorb all the energy of the electrons while the same momentum muons pass through with minimum ionization losses, and also pass through the hadronic calorimeters without interacting, since they only have electromagnetic and weak interactions.
In this CMS detector slice one sees how the calorimeters perform.
One can see the muon going through all that mass of detectors, while the electrons shower in the electromagnetic calorimeter and are contained.
This post imported from StackExchange Physics at 2014-03-24 04:42 (UCT), posted by SE-user anna v