Perfect Ellipsoid potential

class galpy.potential.PerfectEllipsoidPotential(amp=1.0, a=5.0, b=1.0, c=1.0, zvec=None, pa=None, glorder=50, normalize=False, ro=None, vo=None)

Potential of the perfect ellipsoid (de Zeeuw 1985):

\[\rho(x,y,z) = \frac{\mathrm{amp\,a}}{\pi^2\,bc}\,\frac{1}{(m^2+a^2)^2}\]

where \(\mathrm{amp} = GM\) is the total mass and \(m^2 = x^2+y^2/b^2+z^2/c^2\).

__init__(amp=1.0, a=5.0, b=1.0, c=1.0, zvec=None, pa=None, glorder=50, normalize=False, ro=None, vo=None)

Initialize a perfect ellipsoid potential.

Parameters:

• amp (float or Quantity, optional) – Amplitude to be applied to the potential (default: 1); can be a Quantity with units of mass or G x mass.

• a (float or Quantity, optional) – Scale radius.

• b (float, optional) – Y-to-x axis ratio of the density.

• c (float, optional) – Z-to-x axis ratio of the density.

• zvec (numpy.ndarray, optional) – If set, a unit vector that corresponds to the z axis.

• pa (float or Quantity, optional) – If set, the position angle of the x axis (rad or Quantity).

• glorder (int, optional) – If set, compute the relevant force and potential integrals with Gaussian quadrature of this order.

• ro (float, optional) – Distance scale for translation into internal units (default from configuration file).

• vo (float, optional) – Velocity scale for translation into internal units (default from configuration file).

Notes

• 2018-08-06 - Started - Bovy (UofT)