Particle radiance

The quotient of $d\dot{Φ}$ by $dΩ$, where $d\dot{Φ}$ ̇is the fluence rate of particles propagating within a solid angle $dΩ$ around a specified direction, thus:

$d\dot{Φ}_Ω=\frac{d\dot{Φ}}{dΩ}$

The SI unit of particle radiance is m² s^-1 sr^-1. (ICRP Publication 123, 2013)

ICRP Glossary entry - May 2019