Spherical Shell Potential¶

class galpy.potential.SphericalShellPotential(amp=1.0, a=0.75, normalize=False, ro=None, vo=None)[source]¶

Class that implements the potential of an infinitesimally-thin, spherical shell

\[\rho(r) = \frac{\mathrm{amp}}{4\pi\,a^2}\,\delta(r-a)\]

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

__init__(amp=1.0, a=0.75, normalize=False, ro=None, vo=None)[source]¶

Initialize a spherical shell potential.

Parameters:

amp (float or Quantity, optional) – Mass of the shell (default: 1); can be a Quantity with units of mass or Gxmass.
a (float or Quantity, optional) – Radius of the shell (default: 0.75).
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.; note that because the force is always zero at r < a, this does not work if a > 1.
ro (float or Quantity, optional) – Distance scale for translation into internal units (default from configuration file).
vo (float or Quantity, optional) – Velocity scale for translation into internal units (default from configuration file).

Notes