Plasma parameters (plasmapy.formulary.parameters)

Functions to calculate fundamental plasma parameters.


Alfven_speed(B, density[, ion, z_mean])

Calculate the Alfvén speed.

Bohm_diffusion(T_e, B)

Return the Bohm diffusion coefficient.

Debye_length(T_e, n_e)

Calculate the characteristic decay length for electric fields,

Debye_number(T_e, n_e)

Return the number of electrons within a sphere with a radius of the Debye length.

gyrofrequency(B, particle[, signed, Z, to_hz])

Calculate the particle gyrofrequency in units of radians per second.

gyroradius(B, particle, *[, Vperp, T_i])

Return the particle gyroradius.

Hall_parameter(n, T, B, ion, particle[, …])

Calculate the particle Hall parameter for a plasma.

inertial_length(n, particle)

Calculate a charged particle’s inertial length.

ion_sound_speed(T_e, T_i, ion[, n_e, k, …])

Return the ion sound speed for an electron-ion plasma.

kappa_thermal_speed(T, kappa, particle[, method])

Return the most probable speed for a particle within a Kappa distribution.

lower_hybrid_frequency(B, n_i, ion[, to_hz])

Return the lower hybrid frequency.


Calculate the magnetic energy density.


Calculate the magnetic pressure.

mass_density(density, particle[, z_ratio])

Calculate the mass density from a number density.

plasma_frequency(n, particle[, z_mean, to_hz])

Calculate the particle plasma frequency.

thermal_pressure(T, n)

Return the thermal pressure for a Maxwellian distribution.

thermal_speed(T, particle[, method, mass, ndim])

Return the most probable speed for a particle within a Maxwellian distribution.

upper_hybrid_frequency(B, n_e[, to_hz])

Return the upper hybrid frequency.


PlasmaPy provides short-named (alias) versions of the most common plasma functionality. These aliases are only given to functionality where there is a common lexicon in the community, for example plasma_frequency has the alias wp_. All aliases in PlasmaPy are denoted with a trailing underscore _.

betaH_(n, T, B, ion, particle[, …])

Alias to Hall_parameter().

cs_(T_e, T_i, ion[, n_e, k, gamma_e, …])

Alias to ion_sound_speed().

cwp_(n, particle)

Alias to inertial_length().

DB_(T_e, B)

Alias to Bohm_diffusion().

lambdaD_(T_e, n_e)

Alias to Debye_length().

nD_(T_e, n_e)

Alias to Debye_number().

oc_(B, particle[, signed, Z, to_hz])

Alias to gyrofrequency().


Alias to magnetic_pressure().

pth_(T, n)

Alias to thermal_pressure().

rc_(B, particle, *[, Vperp, T_i])

Alias to gyroradius().

rho_(density, particle[, z_ratio])

Alias to mass_density().

rhoc_(B, particle, *[, Vperp, T_i])

Alias to gyroradius().


Alias to magnetic_energy_density().

va_(B, density[, ion, z_mean])

Alias to Alfven_speed().

vth_(T, particle[, method, mass, ndim])

Alias to thermal_speed().

vth_kappa_(T, kappa, particle[, method])

Alias to kappa_thermal_speed().

wc_(B, particle[, signed, Z, to_hz])

Alias to gyrofrequency().

wlh_(B, n_i, ion[, to_hz])

Alias to lower_hybrid_frequency().

wp_(n, particle[, z_mean, to_hz])

Alias to plasma_frequency().

wuh_(B, n_e[, to_hz])

Alias to upper_hybrid_frequency().