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Double power-law density spherical potential

class galpy.potential.TwoPowerSphericalPotential(amp=1.0, a=1.0, alpha=1.0, beta=3.0, normalize=False)

Class that implements spherical potentials that are derived from two-power density models

A
rho(r)= ————————————
(r/a)^lpha (1+r/a)^(eta-lpha)
__init__(amp=1.0, a=1.0, alpha=1.0, beta=3.0, normalize=False)

NAME:

__init__

PURPOSE:

initialize a two-power-density potential

INPUT:

amp - amplitude to be applied to the potential (default: 1)

a - “scale” (in terms of Ro)

alpha - inner power

beta - outer power

normalize - 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.

OUTPUT:

(none)

HISTORY:

2010-07-09 - Started - Bovy (NYU)