inertial_length¶
-
plasmapy.formulary.parameters.
inertial_length
(n: Unit("1 / m3"), particle: plasmapy.particles.particle_class.Particle) -> Unit("m")¶ Calculate a charged particle’s inertial length.
Aliases:
cwp_
Parameters: Returns: d – The particle’s inertial length in meters.
Return type: Raises: TypeError
– If n not aQuantity
or particle is not a string.UnitConversionError
– If n is not in units of a number density.ValueError
– The particle density does not have an appropriate value.
Warns: ~astropy.units.UnitsWarning – If units are not provided and SI units are assumed.
Notes
The inertial length of a particle of species \(s\) is given by
\[d = \frac{c}{\omega_{ps}}\]The inertial length is the characteristic length scale for a particle to be accelerated in a plasma. The Hall effect becomes important on length scales shorter than the ion inertial length.
The inertial length is also known as the skin depth.
Example
>>> from astropy import units as u >>> inertial_length(5 * u.m ** -3, 'He+') <Quantity 2.02985...e+08 m> >>> inertial_length(5 * u.m ** -3, 'e-') <Quantity 2376534.75... m>