Debye_length¶

plasmapy.formulary.
Debye_length
(T_e: Unit(‘K’), n_e: Unit(‘1 / m3’))¶  Calculate the characteristic decay length for electric fields,
due to charge screening.
Aliases:
lambdaD_
 Parameters
 Returns
lambda_D – The Debye length in meters.
 Return type
 Raises
UnitConversionError – If either argument is in incorrect units.
ValueError – If either argument contains invalid values.
 Warns
UnitsWarning
– If units are not provided, SI units are assumed.
Notes
The Debye length is the exponential scale length for charge screening and is given by
\[λ_D = \sqrt{\frac{ε_0 k_b T_e}{n_e e^2}}\]for an electron plasma with nearly stationary ions.
The electrical potential will drop by a factor of \(1/e\) every Debye length.
Plasmas will generally be quasineutral on length scales significantly larger than the Debye length.
See also
Example
>>> from astropy import units as u >>> Debye_length(5e6*u.K, 5e15*u.m**3) <Quantity 0.002182... m>