shamrock.phys.epstein_stopping_time

shamrock.phys.epstein_stopping_time(*, rho_grain: float, s_grain: float, rho: float, cs: float, gamma: float, f: float = 1.0) → float

Epstein drag stopping time for spherical dust grains.

f[t_s = frac{rho_{rm grain} , s_{rm grain}}{rho , c_s , f} sqrt{frac{pi gamma}{8}}f]

where f$rho = rho_{rm g} + rho_{rm d}f$ is the total density and f$ff$ is the supersonic correction factor.

Args:

rho_grain: Internal density of the dust grain s_grain: Radius of the dust grain rho: Total density (f$rho_{rm g} + rho_{rm d}f$) cs: Gas sound speed gamma: Adiabatic index f: Supersonic correction factor (1.0 for subsonic)

Returns:

The stopping time