Stellar Spectra Dust Attenuation¶
Class implementing dust attenuation of stellar spectra—the wavelength-dependent extinction (in magnitudes) applied to the intrinsic spectral energy distribution of a stellar population to model the absorption and scattering of starlight by interstellar dust grains. The attenuation depends on wavelength (following an extinction curve such as Calzetti or Charlot-Fall), the age of the stellar population (young stars embedded in birth clouds are more obscured), and the overall V-band optical depth. Both separable and non-separable implementations are supported.
Default implementation: stellarSpectraDustAttenuationZero
Methods¶
attenuation→double precisionReturn the attenuation, in magnitudes, of stellar spectra due to dust at the given wavelength, age, and V-band extinction.
double precision, intent(in ) :: wavelength, age, vBandAttenuation
isAgeDependent→logicalReturn true if the attenuation may depend on the age of the stellar population.
isSeparable→logicalReturn true if the attenuation is separable into a product of functions of wavelength, age, and V-band attenuation.
stellarSpectraDustAttenuationCalzetti2000¶
Returns the dust attenuation of stellar spectra according to the model of Calzetti et al. (2000).
stellarSpectraDustAttenuationCardelli1989¶
Returns the dust attenuation of stellar spectra according to the model of Cardelli et al. (1989).
Methods
a— Return fitting function \(a(x)\) for the dust attenuation model of Cardelli et al. (1989).b— Return fitting function \(b(x)\) for the dust attenuation model of Cardelli et al. (1989).
Parameters
[Rv](default3.1d0) — The ratio of total to selective extinction \(R_\mathrm{V} = A_\mathrm{V}/E(B-V)\) in the Cardelli et al. (1989) dust attenuation law; the standard Milky Way value is \(R_\mathrm{V} = 3.1\), with smaller values corresponding to greyer extinction curves.
stellarSpectraDustAttenuationCharlotFall2000¶
Returns the dust attenuation of stellar spectra according to the model of Charlot and Fall (2000).
Parameters
[opacityExponent](default0.7d0) — The power-law exponent of wavelength in the opacity \(\tau \propto \lambda^{-n}\) in the Charlot and Fall (2000) two-component dust attenuation model; a value of 0.7 corresponds to the standard parameterization for interstellar and birth cloud attenuation.[birthCloudLifetime](default1.0d-2) — The lifetime of stellar birth clouds (in Gyr) in the Charlot and Fall (2000) dust model; stars younger than this age are attenuated by both the ISM component and the birth cloud component, while older stars experience only ISM attenuation.[opticalDepthISM](default0.5d0) — The effective V-band optical depth \(\hat{\tau}_\mathrm{V}^\mathrm{ISM}\) of the diffuse interstellar medium in the Charlot and Fall (2000) dust attenuation model, applied to all stellar populations regardless of age.[opticalDepthBirthClouds](default1.0d0) — The effective V-band optical depth \(\hat{\tau}_\mathrm{V}^\mathrm{BC}\) of the stellar birth clouds in the Charlot and Fall (2000) dust model, applied only to stellar populations younger thanbirthCloudLifetime; must exceedopticalDepthISM.[filterName]— The filter to select.[filterType]— The filter type (rest or observed) to select.[redshiftBand]— The redshift of the band (if not the output redshift).[depthOpticalISMCoefficient](default1.0d0) — Multiplicative coefficient for optical depth in the ISM.[depthOpticalCloudsCoefficient](default1.0d0) — Multiplicative coefficient for optical depth in birth clouds.[wavelengthExponent](default0.7d0) — Exponent of wavelength in the optical depth.
stellarSpectraDustAttenuationGordon2003¶
Returns the dust attenuation of stellar spectra according to the model of Gordon et al. (2003).
Parameters
[sample](defaultvar_str('SMCbar')) — The name of the sample from Gordon et al. (2003) to use in dust attenuation calculations.
stellarSpectraDustAttenuationPrevotBouchet¶
Returns the dust attenuation of stellar spectra according to the model of Prevot et al. (1984) and Bouchet et al. (1985).
Parameters
[Rv](default2.7d0) — The ratio of total to selective extinction \(R_\mathrm{V} = A_\mathrm{V}/E(B-V)\) in the Prevot et al. (1984)/Bouchet et al. (1985) SMC-like dust attenuation law; the default value of 2.7 is typical for the Small Magellanic Cloud, which lacks the 2175 AAbump seen in Milky Way dust.
stellarSpectraDustAttenuationTabulated¶
Returns the dust attenuation of stellar spectra from a tabulated relation.
Methods
parameters— Return parameters of the current mass distribution.factoryTabulation— Return an instance of the class with the given tabulation parameters.suffix— Return a suffix to append to table file names.fileRead— Read tabulation data from file.fileWrite— Write tabulation data to file.tabulate— (Re)tabulate the mass distribution.interpolate— Interpolate in the mass distribution.isTabulating— Return true if the thread associated with the object is tabulating.velocityDispersion1D— Compute the 1D velocity dispersion at the given coordinates.initialize— Initialize the container (specifically the number of parameters).nameParameter— Return the name of the index parameter for a given tabulation.countParameters— Return the number of parameters for a given tabulation.
Parameters
[toleranceRelativeVelocityDispersion](default1.0d-6) — The relative tolerance to use in numerical solutions for the velocity dispersion in dark-matter-only density profiles.[toleranceRelativeVelocityDispersionMaximum](default1.0d-3) — The maximum relative tolerance to use in numerical solutions for the velocity dispersion in dark-matter-only density profiles.
stellarSpectraDustAttenuationWittGordon2000¶
Returns the dust attenuation of stellar spectra according to the model of Witt and Gordon (2000).
Parameters
[model](defaultvar_str('MilkyWayShellTau3.0')) — The name of the model from Witt and Gordon (2000) to use in dust attenuation calculations.
stellarSpectraDustAttenuationZero¶
Returns zero dust attenuation (an attenuation factor of unity) at all wavelengths, used to disable dust effects while still satisfying the interface requirements of the stellar spectra dust attenuation class.
(Default implementation)
Parameters
[dimensionless](default.true.) — If true the null profile is considered to be dimensionless.