extinction.calzetti00

extinction.calzetti00(wave, a_v, r_v, unit='aa', out=None)

Calzetti (2000) extinction function.

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. They estimate \(R_V = 4.05 \pm 0.80\) from optical-IR observations of 4 starburst galaxies.

Parameters:
wave : numpy.ndarray (1-d)

Wavelengths or wavenumbers.

a_v : float

Scaling parameter, A_V: extinction in magnitudes at characteristic V band wavelength.

r_v : float

Ratio of total to selective extinction, A_V / E(B-V).

unit : {‘aa’, ‘invum’}, optional

Unit of wave: ‘aa’ (Angstroms) or ‘invum’ (inverse microns).

out : np.ndarray, optional

If specified, store output values in this array.

Returns:
Extinction in magnitudes at each input wavelength.