Miyamoto-Nagai potential¶

class galpy.potential.MiyamotoNagaiPotential(amp=1.0, a=1.0, b=0.1, normalize=False, ro=None, vo=None)[source]¶

Class that implements the Miyamoto-Nagai potential [1]

\[\Phi(R,z) = -\frac{\mathrm{amp}}{\sqrt{R^2+(a+\sqrt{z^2+b^2})^2}}\]

with \(\mathrm{amp} = GM\) the total mass.

__init__(amp=1.0, a=1.0, b=0.1, normalize=False, ro=None, vo=None)[source]¶

Initialize a Miyamoto-Nagai potential.

Parameters:

amp (float or Quantity, optional) – Amplitude to be applied to the potential, the total mass (default: 1); can be a Quantity with units of mass or Gxmass.
a (float or Quantity, optional) – Scale length.
b (float or Quantity, optional) – Scale height.
normalize (bool or float, optional) – If True, normalize such that vc(1.,0.)=1., or, if given as a number, such that the force is this fraction of the force necessary to make vc(1.,0.)=1.
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

References