**Definition:**The anisotropy factor,g, is the average cosine of the scattering angle for a typical scattering event, i.e., . For example, if each scatter tends to scatter incident photons into the forward direction, then the anisotropy factor will be close to unity; if the scattering tends to be isotropic, then the factor will be close to zero. The anisotropy factor can also define single scattering events.Definition: The anisotropy factor,g, is the average cosine of the scattering angle for a typical scattering event, i.e., . For example, if each scatter tends to scatter incident photons into the forward direction, then the anisotropy factor will be close to unity; if the scattering tends to be isotropic, then the factor will be close to zero. The anisotropy factor can also define single scattering events.

**Alternative definition:**

**Synonym:**Asymmetry factor

**References:**https://doi.org/10.1117/3.2624517

**Related terms:**Scattering phase function, Reduced scattering coefficient