mhd_waves

plasmapy.dispersion.analytical.mhd_waves_.mhd_waves(*args, **kwargs)

Returns a dictionary containing objects of the three magnetohydrodynamic waves with identical parameters.

Parameters:

• B (Quantity) – The magnetic field magnitude in units convertible to T.

• density (Quantity) – Either the ion number density \(n_i\) in units convertible to m^-3 or the total mass density \(ρ\) in units convertible to kg m^-3.

• ion (particle-like) – Representation of the ion species (e.g., 'p+' for protons, 'D+' for deuterium, 'He-4 +1' for singly ionized helium-4, etc.). If no charge state information is provided, then the ions are assumed to be singly ionized.

• T (Quantity, keyword-only, default: 0 K) – The plasma temperature in units of K or eV.

• gamma (float or int, keyword-only, default: 5/3) – The adiabatic index for the plasma.

• mass_numb (‘int’, keyword-only, optional) – The mass number corresponding to ion.

• Z (float or ‘int’, keyword-only, optional) – The charge number corresponding to ion.

Returns:

mhd_waves – A named tuple of magnetohydrodynamic-wave objects. It contains three keys: 'alfven' for the Alfvén mode, 'fast' for the fast magnetosonic mode, and 'slow' for the slow magnetosonic mode.

Return type:

namedtuple[str, AlfvenWave or FastMagnetosonicWave or SlowMagnetosonicWave]

Raises:

• TypeError – If applicable arguments are not instances of Quantity or cannot be converted into one.

• TypeError – If ion is not particle-like.

• TypeError – If gamma or Z are not of type int or float.

• TypeError – If mass_numb is not of type int.

• UnitTypeError – If applicable arguments do not have units convertible to the expected units.

• ValueError – If any of B, density, or T is negative.

• ValueError – If ion is not of category ion or element.

• ValueError – If B, density, or T are not single-valued astropy.units.Quantity (i.e. an array).