inertial_length
- plasmapy.formulary.lengths.inertial_length(n: Unit('1 / m3'), particle: str | Integral | Particle | CustomParticle | Quantity)
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
is not aQuantity
orparticle
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:
UnitsWarning
– If units are not provided and SI units are assumed.
Notes
The inertial length of a particle of species \(s\) is given by
\[d = \frac{c}{ω_{ps}}\]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.
Examples
>>> 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>