treams.special.vsw_M

treams.special.vsw_M(l, m, x, theta, phi) = <ufunc 'vsw_M'>

Singular vector spherical wave M

The vector spherical wave is defined by \(\boldsymbol M_{lm}^{(3)} (x, \theta, \varphi) = h_l^{(1)} (x) \boldsymbol X_{lm}(\theta, \varphi)\) using treams.special.spherical_hankel1() and treams.special.vsh_X().

This function is describing a transverse solution to the vectorial Helmholtz wave equation, that is also tangential on a spherical surface. This is often used to describe a transverse electric (in spherical coordinates) (TE) wave. Additionally, the term magnetic (refferring to the multipole) is used for this solution.

Parameters:
  • l (int, array_like) – Degree \(l \geq 0\)

  • m (int, array_like) – Order \(|m| \leq l\)

  • x (float or complex, array_like) – Distance in units of the wave number \(kr\)

  • theta (float or complex, array_like) – Polar angle

  • phi (float, array_like) – Azimuthal angle

Returns:

complex, 3-array