Calzetti00

class beast.physicsmodel.dust.attenuation.Calzetti00[source]

Bases: beast.physicsmodel.dust.extinction.ExtinctionLaw

Calzetti et al. (2000, ApJ 533, 682) developed a recipe for dereddening the spectra of galaxies where massive stars dominate the radiation output, valid between 0.12 to 2.2 microns. Extrapolation down to 0.0912 microns

Note that the supplied color excess should be that derived for the stellar continuum, EBV(stars), which is related to the reddening derived from the gas, EBV(gas), via the Balmer decrement by EBV(stars) = 0.44 times EBV(gas)

R_V - Ratio of total to selective extinction, default is 4.05. Calzetti et al. (2000) estimate R_V = 4.05 +/- 0.80 from optical-IR observations of 4 starbursts.

Methods Summary

function(lamb[, Av, Rv, Alambda]) Returns A(lambda) or tau for the Calzetti Law

Methods Documentation

function(lamb, Av=1, Rv=4.05, Alambda=True, **kwargs)[source]

Returns A(lambda) or tau for the Calzetti Law

Parameters:

lamb: float or ndarray(dtype=float)

wavelength [in Angstroms] at which evaluate the law.

Av: float

desired A(V) (default 1.0)

Rv: float

desired R(V) (default 4.05)

Alambda: bool

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

Returns:

r: float or ndarray(dtype=float)

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