# Third-party
import astropy.units as u
import numpy as np
# Project
from gala.potential.potential.builtin.core import (
HernquistPotential,
LogarithmicPotential,
MiyamotoNagaiPotential,
MN3ExponentialDiskPotential,
NFWPotential,
PowerLawCutoffPotential,
)
from gala.potential.potential.ccompositepotential import CCompositePotential
from gala.units import galactic
__all__ = [
"LM10Potential",
"MilkyWayPotential",
"MilkyWayPotential2022",
"BovyMWPotential2014",
]
[docs]
class LM10Potential(CCompositePotential):
"""
The Galactic potential used by Law and Majewski (2010) to represent
the Milky Way as a three-component sum of disk, bulge, and halo.
The disk potential is an axisymmetric
:class:`~gala.potential.MiyamotoNagaiPotential`, the bulge potential
is a spherical :class:`~gala.potential.HernquistPotential`, and the
halo potential is a triaxial :class:`~gala.potential.LogarithmicPotential`.
Default parameters are fixed to those found in LM10 by fitting N-body
simulations to the Sagittarius stream.
Parameters
----------
units : `~gala.units.UnitSystem` (optional)
Set of non-reducable units that specify (at minimum) the
length, mass, time, and angle units.
disk : dict (optional)
Parameters to be passed to the :class:`~gala.potential.MiyamotoNagaiPotential`.
bulge : dict (optional)
Parameters to be passed to the :class:`~gala.potential.HernquistPotential`.
halo : dict (optional)
Parameters to be passed to the :class:`~gala.potential.LogarithmicPotential`.
Note: in subclassing, order of arguments must match order of potential
components added at bottom of init.
"""
def __init__(self, units=galactic, disk=dict(), bulge=dict(), halo=dict()):
default_disk = dict(m=1e11 * u.Msun, a=6.5 * u.kpc, b=0.26 * u.kpc)
default_bulge = dict(m=3.4e10 * u.Msun, c=0.7 * u.kpc)
default_halo = dict(
q1=1.38,
q2=1.0,
q3=1.36,
r_h=12.0 * u.kpc,
phi=97 * u.degree,
v_c=np.sqrt(2) * 121.858 * u.km / u.s,
)
for k, v in default_disk.items():
if k not in disk:
disk[k] = v
for k, v in default_bulge.items():
if k not in bulge:
bulge[k] = v
for k, v in default_halo.items():
if k not in halo:
halo[k] = v
super().__init__()
self["disk"] = MiyamotoNagaiPotential(units=units, **disk)
self["bulge"] = HernquistPotential(units=units, **bulge)
self["halo"] = LogarithmicPotential(units=units, **halo)
self.lock = True
[docs]
class MilkyWayPotential(CCompositePotential):
"""
A simple mass-model for the Milky Way consisting of a spherical nucleus and
bulge, a Miyamoto-Nagai disk, and a spherical NFW dark matter halo.
The disk model is taken from `Bovy (2015)
<https://ui.adsabs.harvard.edu/#abs/2015ApJS..216...29B/abstract>`_ - if you
use this potential, please also cite that work.
Default parameters are fixed by fitting to a compilation of recent mass
measurements of the Milky Way, from 10 pc to ~150 kpc.
Parameters
----------
units : `~gala.units.UnitSystem` (optional)
Set of non-reducable units that specify (at minimum) the
length, mass, time, and angle units.
disk : dict (optional)
Parameters to be passed to the :class:`~gala.potential.MiyamotoNagaiPotential`.
bulge : dict (optional)
Parameters to be passed to the :class:`~gala.potential.HernquistPotential`.
halo : dict (optional)
Parameters to be passed to the :class:`~gala.potential.NFWPotential`.
nucleus : dict (optional)
Parameters to be passed to the :class:`~gala.potential.HernquistPotential`.
Note: in subclassing, order of arguments must match order of potential
components added at bottom of init.
"""
def __init__(self, units=galactic, disk=None, halo=None, bulge=None, nucleus=None):
default_disk = dict(m=6.8e10 * u.Msun, a=3.0 * u.kpc, b=0.28 * u.kpc)
default_bulge = dict(m=5e9 * u.Msun, c=1.0 * u.kpc)
default_nucl = dict(m=1.71e9 * u.Msun, c=0.07 * u.kpc)
default_halo = dict(m=5.4e11 * u.Msun, r_s=15.62 * u.kpc)
if disk is None:
disk = dict()
if halo is None:
halo = dict()
if bulge is None:
bulge = dict()
if nucleus is None:
nucleus = dict()
for k, v in default_disk.items():
if k not in disk:
disk[k] = v
for k, v in default_bulge.items():
if k not in bulge:
bulge[k] = v
for k, v in default_halo.items():
if k not in halo:
halo[k] = v
for k, v in default_nucl.items():
if k not in nucleus:
nucleus[k] = v
super().__init__()
self["disk"] = MiyamotoNagaiPotential(units=units, **disk)
self["bulge"] = HernquistPotential(units=units, **bulge)
self["nucleus"] = HernquistPotential(units=units, **nucleus)
self["halo"] = NFWPotential(units=units, **halo)
self.lock = True
[docs]
class MilkyWayPotential2022(CCompositePotential):
"""
A mass-model for the Milky Way consisting of a spherical nucleus and bulge, a
3-component sum of Miyamoto-Nagai disks to represent an exponential disk, and a
spherical NFW dark matter halo.
The disk model is fit to the Eilers et al. 2019 rotation curve for the radial
dependence, and the shape of the phase-space spiral in the solar neighborhood is
used to set the vertical structure in Darragh-Ford et al. 2023.
Other parameters are fixed by fitting to a compilation of recent mass measurements
of the Milky Way, from 10 pc to ~150 kpc.
Parameters
----------
units : `~gala.units.UnitSystem` (optional)
Set of non-reducable units that specify (at minimum) the
length, mass, time, and angle units.
disk : dict (optional)
Parameters to be passed to the
:class:`~gala.potential.MN3ExponentialDiskPotential`.
bulge : dict (optional)
Parameters to be passed to the :class:`~gala.potential.HernquistPotential`.
halo : dict (optional)
Parameters to be passed to the :class:`~gala.potential.NFWPotential`.
nucleus : dict (optional)
Parameters to be passed to the :class:`~gala.potential.HernquistPotential`.
Note: in subclassing, order of arguments must match order of potential
components added at bottom of init.
"""
def __init__(self, units=galactic, disk=None, halo=None, bulge=None, nucleus=None):
default_disk = dict(m=4.7717e10 * u.Msun, h_R=2.6 * u.kpc, h_z=0.3 * u.kpc)
default_bulge = dict(m=5e9 * u.Msun, c=1.0 * u.kpc)
default_nucl = dict(m=1.8142e9 * u.Msun, c=0.0688867 * u.kpc)
default_halo = dict(m=5.5427e11 * u.Msun, r_s=15.626 * u.kpc)
if disk is None:
disk = dict()
if halo is None:
halo = dict()
if bulge is None:
bulge = dict()
if nucleus is None:
nucleus = dict()
for k, v in default_disk.items():
if k not in disk:
disk[k] = v
for k, v in default_bulge.items():
if k not in bulge:
bulge[k] = v
for k, v in default_halo.items():
if k not in halo:
halo[k] = v
for k, v in default_nucl.items():
if k not in nucleus:
nucleus[k] = v
super().__init__()
self["disk"] = MN3ExponentialDiskPotential(units=units, **disk)
self["bulge"] = HernquistPotential(units=units, **bulge)
self["nucleus"] = HernquistPotential(units=units, **nucleus)
self["halo"] = NFWPotential(units=units, **halo)
self.lock = True
[docs]
class BovyMWPotential2014(CCompositePotential):
"""
An implementation of the ``MWPotential2014``
`from galpy <https://galpy.readthedocs.io/en/latest/potential.html>`_
and described in `Bovy (2015)
<https://ui.adsabs.harvard.edu/#abs/2015ApJS..216...29B/abstract>`_.
This potential consists of a spherical bulge and dark matter halo, and a
Miyamoto-Nagai disk component.
.. note::
Because it internally uses the PowerLawCutoffPotential,
this potential requires GSL to be installed, and Gala must have been
built and installed with GSL support enaled (the default behavior).
See http://gala.adrian.pw/en/latest/install.html for more information.
Parameters
----------
units : `~gala.units.UnitSystem` (optional)
Set of non-reducable units that specify (at minimum) the
length, mass, time, and angle units.
disk : dict (optional)
Parameters to be passed to the :class:`~gala.potential.MiyamotoNagaiPotential`.
bulge : dict (optional)
Parameters to be passed to the :class:`~gala.potential.PowerLawCutoffPotential`.
halo : dict (optional)
Parameters to be passed to the :class:`~gala.potential.NFWPotential`.
Note: in subclassing, order of arguments must match order of potential
components added at bottom of init.
"""
def __init__(self, units=galactic, disk=None, halo=None, bulge=None):
default_disk = dict(m=68193902782.346756 * u.Msun, a=3.0 * u.kpc, b=280 * u.pc)
default_bulge = dict(m=4501365375.06545 * u.Msun, alpha=1.8, r_c=1.9 * u.kpc)
default_halo = dict(m=4.3683325e11 * u.Msun, r_s=16 * u.kpc)
if disk is None:
disk = dict()
if halo is None:
halo = dict()
if bulge is None:
bulge = dict()
for k, v in default_disk.items():
if k not in disk:
disk[k] = v
for k, v in default_bulge.items():
if k not in bulge:
bulge[k] = v
for k, v in default_halo.items():
if k not in halo:
halo[k] = v
super().__init__()
self["disk"] = MiyamotoNagaiPotential(units=units, **disk)
self["bulge"] = PowerLawCutoffPotential(units=units, **bulge)
self["halo"] = NFWPotential(units=units, **halo)
self.lock = True
# --------------------------------------------------------------------
# class TriaxialMWPotential(CCompositePotential):
# def __init__(self, units=galactic,
# disk=dict(), bulge=dict(), halo=dict()):
# """ Axis ratio values taken from Jing & Suto (2002). Other
# parameters come from a by-eye fit to Bovy's MW2014Potential.
# Choice of v_c sets circular velocity at Sun to 220 km/s
# """
# default_disk = dict(m=7E10, a=3.5, b=0.14)
# default_bulge = dict(m=1E10, c=1.1)
# default_halo = dict(a=1., b=0.75, c=0.55,
# v_c=0.239225, r_s=30.,
# phi=0., theta=0., psi=0.)
# for k, v in default_disk.items():
# if k not in disk:
# disk[k] = v
# for k, v in default_bulge.items():
# if k not in bulge:
# bulge[k] = v
# for k, v in default_halo.items():
# if k not in halo:
# halo[k] = v
# kwargs = dict()
# kwargs["disk"] = MiyamotoNagaiPotential(units=units, **disk)
# kwargs["bulge"] = HernquistPotential(units=units, **bulge)
# kwargs["halo"] = LeeSutoTriaxialNFWPotential(units=units, **halo)
# super(TriaxialMWPotential, self).__init__(**kwargs)
# --------------------------------------------------------------------
