Gordon16_RvFALaw

class beast.physicsmodel.dust.extinction.Gordon16_RvFALaw[source]

Bases: ExtinctionLaw

Gordon16 RvFA extinction law

Mixture of Milky Way R(V) dependent extinction law and Gordon et al. (2003) SMCBar average extinction curve.

This extinction curve model encompasses the average behavior of measured extinction curves in the Milky Way, LMC, and SMC.

Implemented as a mixture between Fitzpatrick99 and Gordon03_SMCBar classes

Methods Summary

function(lamb[, Av, Rv, Alambda, f_A])

Gordon16_RvFALaw

get_Rv(Rv_A[, f_A])

Calculate the Rv of the mixture law given R(V) of the A component

get_Rv_A(Rv[, f_A])

Calculate the R(V) of the A component given the R(V) of the mixture

Methods Documentation

function(lamb, Av=1, Rv=3.1, Alambda=True, f_A=0.5, **kwargs)[source]

Gordon16_RvFALaw

Parameters:

  • lamb (float or ndarray(dtype=float)) – wavelength [in Angstroms] at which to evaluate the law.

  • Av (float) – desired A(V) (default 1.0)

  • Alambda (bool) – if set returns +2.5*1./log(10.)*tau, tau otherwise

  • f_A (float) – set the mixture ratio between the two laws (default 0.5)

  • Rv (float) – R(V) of mixture law (default to 3.1)

Returns:

r – attenuation as a function of wavelength depending on Alambda option +2.5*1./log(10.)*tau, or tau

Return type:

float or ndarray(dtype=float)

get_Rv(Rv_A, f_A=0.5)[source]

Calculate the Rv of the mixture law given R(V) of the A component

Rv_A is such that:

1 / Rv = f_A / Rv_A + (1 - f_A) / Rv_B

where Rv_B = 2.74 by definition (see Gordon03_SMCBar)

Parameters:

  • Rv_A (float) – R(V) of the A component

  • f_A (float) – Mixture ratio between the two components [default is 0.5]

Returns:

Rv – R(V) of the mixture

Return type:

float

get_Rv_A(Rv, f_A=0.5)[source]

Calculate the R(V) of the A component given the R(V) of the mixture

Rv_A is such that:

1 / Rv = f_A / Rv_A + (1 - f_A) / Rv_B

Rv_A = 1. / (1. / (Rv * f_A) - (1. - f_A) / (f_A * Rv_B))

where Rv_B = 2.74 by definition (see Gordon03_SMCBar)

Parameters:

  • Rv (float) – R(V) of the mixture law

  • f_A (float) – Mixture ratio between the two components [default is 0.5]

Returns:

Rv_A – R(V) of the A componet

Return type:

float