Radiological Training for Accelerator Facilities
than protons or heavier particles. Some machines, called light sources, accelerate electrons
and positrons specifically for the purpose of producing synchrotron radiation.
DISCUSS special instruments and measurement techniques.
Neutrons can be produced through nuclear interactions of the primary or secondary beam
with matter. They can also be produced by interaction of high-energy photons with matter
(photonuetron reaction). The photoneutron reaction typically requires photons with energy
interact with matter, such as targets, beamline components, etc.
Neutrons do not lose energy by direct ionization like charged particles. They gradually lose
their energy through collisions with atoms in material. The most effective shielding is
material that contains hydrogen, such as concrete, earth, or water. When a neutron collides
with a hydrogen nucleus containing one proton, the neutron transfers energy to the proton
(like two billiard balls colliding). The proton is easily stopped because it is a charged
Labyrinth designs are often used to "trap" neutrons as they ricochet.
Location of potential sources of neutron radiation exposure. (Facility Specific)
Muons are short-lived particles that are physically similar to electrons, but about 200 times
Muons are produced by several mechanisms and require photon energies greater than 212
MeV or proton energies greater than 140 MeV. Muons are not usually seen in significant
amounts at machines with energies less than 1 giga volt (GeV = 1x109 eV).