Generalization of the lopsided and elliptical disk potentials to any m.
Class that implements the disk potential
This potential can be grown between \(t_{\mathrm{form}}\) and \(t_{\mathrm{form}}+T_{\mathrm{steady}}\) in a similar way as DehnenBarPotential, but times are given directly in galpy time units
NAME:
__init__
PURPOSE:
initialize an cosmphi disk potential
phi(R,phi) = phio (R/Ro)^p cos[m(phi-phib)]
INPUT:
amp= amplitude to be applied to the potential (default: 1.), see twophio below
tform= start of growth (to smoothly grow this potential
tsteady= time delay at which the perturbation is fully grown (default: 2.)
m= cos( m * (phi - phib) )
p= power-law index of the phi(R) = (R/Ro)^p part
Either:
phib= angle (in rad; default=25 degree)
phio= potential perturbation (in terms of phio/vo^2 if vo=1 at Ro=1)
cp, sp= m * phio * cos(m * phib), m * phio * sin(m * phib)
OUTPUT:
(none)
HISTORY:
2011-10-27 - Started - Bovy (IAS)