Three Miyamoto-Nagai disk approximation to an exponential disk¶
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class
galpy.potential.
MN3ExponentialDiskPotential
(amp=1.0, hr=0.3333333333333333, hz=0.0625, sech=False, posdens=False, normalize=False, ro=None, vo=None)¶ class that implements the three Miyamoto-Nagai approximation to a radially-exponential disk potential of Smith et al. 2015
\[\rho(R,z) = \mathrm{amp}\,\exp\left(-R/h_R-|z|/h_z\right)\]or
\[\rho(R,z) = \mathrm{amp}\,\exp\left(-R/h_R\right)\mathrm{sech}^2\left(-|z|/h_z\right)\]depending on whether sech=True or not. This density is approximated using three Miyamoto-Nagai disks
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__init__
(amp=1.0, hr=0.3333333333333333, hz=0.0625, sech=False, posdens=False, normalize=False, ro=None, vo=None)¶ NAME:
__init__PURPOSE:
initialize a 3MN approximation to an exponential disk potentialINPUT:
amp - amplitude to be applied to the potential (default: 1); can be a Quantity with units of mass density or Gxmass density
hr - disk scale-length (can be Quantity)
hz - scale-height (can be Quantity)
sech= (False) if True, hz is the scale height of a sech vertical profile (default is exponential vertical profile)
posdens= (False) if True, allow only positive density solutions (Table 2 in Smith et al. rather than Table 1)
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.
ro=, vo= distance and velocity scales for translation into internal units (default from configuration file)
OUTPUT:
MN3ExponentialDiskPotential objectHISTORY:
2015-02-07 - Written - Bovy (IAS)
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