The number of radiant-energy particles emitted from or incident on a surface in a given period of time, divided by the area of the surface.
NOTE 1 The equation "fluence = N/A" applies, where N and A represent the quantities number of particles and area. Fluence can also be calculated by integrating the flux density over the given period of time, e.g., as in a run.
NOTE 2 The unit symbol (e.g., cm‑²) does not identify particle type. The particle name may be placed before the term, e.g., "neutron fluence", or in the spelled-out unit name, e.g., "neutrons per square centimeter".
NOTE 3 Fluence of particle radiation incident on a surface is maximized when the surface is perpendicular to the direction of the incident particle flow.
Contact Julie Carlson, 703-624-9230