"""A module for holding blackhole emission models.
The class defined here should never be instantiated directly, there are only
ever instantiated by the parametric/particle child classes.
BlackholesComponent is a child class of Component.
"""
import numpy as np
from unyt import Msun, c, cm, deg, erg, km, s, yr
from synthesizer import exceptions
from synthesizer.components.component import Component
from synthesizer.units import Quantity, accepts
from synthesizer.utils import TableFormatter
[docs]
class BlackholesComponent(Component):
"""
The parent class for stellar components of a galaxy.
This class contains the attributes and spectra creation methods which are
common to both parametric and particle stellar components.
This should never be instantiated directly, instead it provides the common
functionality and attributes used by the child parametric and particle
BlackHole/s classes.
Attributes:
spectra (dict, Sed)
A dictionary containing black hole spectra.
mass (array-like, float)
The mass of each blackhole.
accretion_rate (array-like, float)
The accretion rate of each blackhole.
epsilon (array-like, float)
The radiative efficiency of the blackhole.
accretion_rate_eddington (array-like, float)
The accretion rate expressed as a fraction of the Eddington
accretion rate.
inclination (array-like, float)
The inclination of the blackhole disc.
spin (array-like, float)
The dimensionless spin of the blackhole.
bolometric_luminosity (array-like, float)
The bolometric luminosity of the blackhole.
metallicity (array-like, float)
The metallicity of the blackhole which is assumed for the line
emitting regions.
Attributes (For EmissionModels):
ionisation_parameter_blr (array-like, float)
The ionisation parameter of the broad line region.
hydrogen_density_blr (array-like, float)
The hydrogen density of the broad line region.
covering_fraction_blr (array-like, float)
The covering fraction of the broad line region (effectively
the escape fraction).
velocity_dispersion_blr (array-like, float)
The velocity dispersion of the broad line region.
ionisation_parameter_nlr (array-like, float)
The ionisation parameter of the narrow line region.
hydrogen_density_nlr (array-like, float)
The hydrogen density of the narrow line region.
covering_fraction_nlr (array-like, float)
The covering fraction of the narrow line region (effectively
the escape fraction).
velocity_dispersion_nlr (array-like, float)
The velocity dispersion of the narrow line region.
theta_torus (array-like, float)
The angle of the torus.
torus_fraction (array-like, float)
The fraction of the torus angle to 90 degrees.
"""
# Define class level Quantity attributes
accretion_rate = Quantity("mass_rate")
inclination = Quantity("angle")
bolometric_luminosity = Quantity("luminosity")
eddington_luminosity = Quantity("luminosity")
bb_temperature = Quantity("temperature")
mass = Quantity("mass")
@accepts(
mass=Msun.in_base("galactic"),
accretion_rate=Msun.in_base("galactic") / yr,
accretion_rate_eddington=Msun.in_base("galactic") / yr,
inclination=deg,
bolometric_luminosity=erg / s,
hydrogen_density_blr=cm**-3,
hydrogen_density_nlr=cm**-3,
velocity_dispersion_blr=km / s,
velocity_dispersion_nlr=km / s,
theta_torus=deg,
)
def __init__(
self,
fesc,
mass=None,
accretion_rate=None,
epsilon=0.1,
accretion_rate_eddington=None,
inclination=0.0 * deg,
spin=None,
bolometric_luminosity=None,
metallicity=None,
ionisation_parameter_blr=0.1,
hydrogen_density_blr=1e9 / cm**3,
covering_fraction_blr=0.1,
velocity_dispersion_blr=2000 * km / s,
ionisation_parameter_nlr=0.01,
hydrogen_density_nlr=1e4 / cm**3,
covering_fraction_nlr=0.1,
velocity_dispersion_nlr=500 * km / s,
theta_torus=10 * deg,
**kwargs,
):
"""
Initialise the BlackholeComponent.
Where they're not provided missing quantities are automatically
calcualted. Not all parameters need to be set for every emission model.
Args:
mass (array-like, float)
The mass of each blackhole.
accretion_rate (array-like, float)
The accretion rate of each blackhole.
epsilon (array-like, float)
The radiative efficiency of the blackhole.
accretion_rate_eddington (array-like, float)
The accretion rate expressed as a fraction of the Eddington
accretion rate.
inclination (array-like, float)
The inclination of the blackhole disc.
spin (array-like, float)
The dimensionless spin of the blackhole.
bolometric_luminosity (array-like, float)
The bolometric luminosity of the blackhole.
metallicity (array-like, float)
The metallicity of the blackhole which is assumed for the line
emitting regions.
ionisation_parameter_blr (array-like, float)
The ionisation parameter of the broadline region.
hydrogen_density_blr (array-like, float)
The hydrogen density of the broad line region.
covering_fraction_blr (array-like, float)
The covering fraction of the broad line region (effectively
the escape fraction).
velocity_dispersion_blr (array-like, float)
The velocity dispersion of the broad line region.
ionisation_parameter_nlr (array-like, float)
The ionisation parameter of the narrow line region.
hydrogen_density_nlr (array-like, float)
The hydrogen density of the narrow line region.
covering_fraction_nlr (array-like, float)
The covering fraction of the narrow line region (effectively
the escape fraction).
velocity_dispersion_nlr (array-like, float)
The velocity dispersion of the narrow line region.
theta_torus (array-like, float)
The angle of the torus.
kwargs (dict)
Any other parameter for the emission models can be provided as
kwargs.
"""
# Initialise the parent class
Component.__init__(self, "BlackHoles", fesc, **kwargs)
# Save the black hole properties
self.mass = mass
self.accretion_rate = accretion_rate
self.epsilon = epsilon
self.accretion_rate_eddington = accretion_rate_eddington
self.spin = spin
self.bolometric_luminosity = bolometric_luminosity
self.metallicity = metallicity
# Below we attach all the possible attributes that could be needed by
# the emission models.
# Set BLR attributes
self.ionisation_parameter_blr = ionisation_parameter_blr
self.hydrogen_density_blr = hydrogen_density_blr
self.covering_fraction_blr = covering_fraction_blr
self.velocity_dispersion_blr = velocity_dispersion_blr
# Set NLR attributes
self.ionisation_parameter_nlr = ionisation_parameter_nlr
self.hydrogen_density_nlr = hydrogen_density_nlr
self.covering_fraction_nlr = covering_fraction_nlr
self.velocity_dispersion_nlr = velocity_dispersion_nlr
# The inclination of the black hole disc
self.inclination = (
inclination if inclination is not None else 0.0 * deg
)
# The angle of the torus
self.theta_torus = theta_torus
self.torus_fraction = (self.theta_torus / (90 * deg)).value
self._torus_edgeon_cond = self.inclination + self.theta_torus
# Check to make sure that both accretion rate and bolometric luminosity
# haven't been provided because that could be confusing.
if (self.accretion_rate is not None) and (
self.bolometric_luminosity is not None
):
raise exceptions.InconsistentArguments(
"""Both accretion rate and bolometric luminosity provided but
that is confusing. Provide one or the other!"""
)
if (self.accretion_rate_eddington is not None) and (
self.bolometric_luminosity is not None
):
raise exceptions.InconsistentArguments(
"""Both accretion rate (in terms of Eddington) and bolometric
luminosity provided but that is confusing. Provide one or
the other!"""
)
# If mass, accretion_rate, and epsilon provided calculate the
# bolometric luminosity.
if (
self.mass is not None
and self.accretion_rate is not None
and self.epsilon is not None
):
self.calculate_bolometric_luminosity()
# If mass, accretion_rate, and epsilon provided calculate the
# big bump temperature.
if (
self.mass is not None
and self.accretion_rate is not None
and self.epsilon is not None
):
self.calculate_bb_temperature()
# If mass calculate the Eddington luminosity.
if self.mass is not None:
self.calculate_eddington_luminosity()
# If mass, accretion_rate, and epsilon provided calculate the
# Eddington ratio.
if (
self.mass is not None
and self.accretion_rate is not None
and self.epsilon is not None
):
self.calculate_eddington_ratio()
# If mass, accretion_rate, and epsilon provided calculate the
# accretion rate in units of the Eddington accretion rate. This is the
# bolometric_luminosity / eddington_luminosity.
if (
self.mass is not None
and self.accretion_rate is not None
and self.epsilon is not None
):
self.calculate_accretion_rate_eddington()
# If inclination, calculate the cosine of the inclination, required by
# some models (e.g. AGNSED).
if self.inclination is not None:
self.cosine_inclination = np.cos(
self.inclination.to("radian").value
)
[docs]
def calculate_bolometric_luminosity(self):
"""
Calculate the black hole bolometric luminosity. This is by itself
useful but also used for some emission models.
Returns
unyt_array
The black hole bolometric luminosity
"""
self.bolometric_luminosity = self.epsilon * self.accretion_rate * c**2
return self.bolometric_luminosity
[docs]
def calculate_eddington_luminosity(self):
"""
Calculate the eddington luminosity of the black hole.
Returns
unyt_array
The black hole bolometric luminosity
"""
# Note: the factor 1.257E38 comes from:
# 4*pi*G*mp*c*Msun/sigma_thompson
self.eddington_luminosity = 1.257e38 * self._mass
return self.eddington_luminosity
[docs]
def calculate_eddington_ratio(self):
"""
Calculate the eddington ratio of the black hole.
Returns
unyt_array
The black hole eddington ratio
"""
self.eddington_ratio = (
self._bolometric_luminosity / self._eddington_luminosity
)
return self.eddington_ratio
[docs]
def calculate_bb_temperature(self):
"""
Calculate the black hole big bump temperature. This is used for the
cloudy disc model.
Returns
unyt_array
The black hole bolometric luminosity
"""
# Calculate the big bump temperature
self.bb_temperature = (
2.24e9 * self._accretion_rate ** (1 / 4) * self._mass**-0.5
)
return self.bb_temperature
[docs]
def calculate_accretion_rate_eddington(self):
"""
Calculate the black hole accretion in units of the Eddington rate.
Returns
unyt_array
The black hole accretion rate in units of the Eddington rate.
"""
self.accretion_rate_eddington = (
self._bolometric_luminosity / self._eddington_luminosity
)
return self.accretion_rate_eddington
def __str__(self):
"""
Return a string representation of the particle object.
Returns:
table (str)
A string representation of the particle object.
"""
# Intialise the table formatter
formatter = TableFormatter(self)
return formatter.get_table("Black Holes")