Dust (extinction correction)

hostphot.dust.calc_extinction(filt, survey, ra, dec, scaling=0.86, reddening_law='fitzpatrick99', r_v=3.1)

Calculates the extinction for a given filter, right ascension and declination or E(B-V).

Parameters:

  • filter_wave (array) – Filter’s wavelength range.

  • filter_response (array) – Filter’s response function.

  • ra (float) – Right ascension.

  • dec (float) – Declinationin degrees.

  • scaling (float, default 0.86) – Calibration of the Milky Way dust maps. Either 0.86 for the Schlafly & Finkbeiner (2011) recalibration or 1.0 for the original dust map of Schlegel, Fikbeiner & Davis (1998).

  • reddening_law (str, default fitzpatrick99) – Reddening law. The options are: ccm89 (Cardelli, Clayton & Mathis 1989), odonnell94 (O’Donnell 1994), fitzpatrick99 (Fitzpatrick 1999), calzetti00 (Calzetti 2000) and fm07 (Fitzpatrick & Massa 2007 with \(R_V\) = 3.1.)

  • r_v (float, default 3.1) – Total-to-selective extinction ratio (\(R_V\))

Returns:

A_ext – Extinction value in magnitudes.

Return type:

float

hostphot.dust.deredden(wave, flux, ra, dec, scaling=0.86, reddening_law='fitzpatrick99', r_v=3.1)

Dereddens the given spectrum, given a right ascension and declination or \(E(B-V)\).

Parameters:

  • wave (array) – Wavelength values.

  • flux (array) – Flux density values.

  • ra (float) – Right ascension in degrees.

  • dec (float) – Declination in degrees.

  • scaling (float, default 0.86) – Calibration of the Milky Way dust maps. Either 0.86 for the Schlafly & Finkbeiner (2011) recalibration or 1.0 for the original dust map of Schlegel, Fikbeiner & Davis (1998).

  • reddening_law (str, default fitzpatrick99) – Reddening law. The options are: ccm89 (Cardelli, Clayton & Mathis 1989), odonnell94 (O’Donnell 1994), fitzpatrick99 (Fitzpatrick 1999), calzetti00 (Calzetti 2000) and fm07 (Fitzpatrick & Massa 2007 with \(R_V\) = 3.1.)

  • dustmaps_dir (str, default None) – Directory where the dust maps of Schlegel, Fikbeiner & Davis (1998) are found.

  • r_v (float, default 3.1) – Total-to-selective extinction ratio (\(R_V\))

  • ebv (float, default None) – Colour excess (\(E(B-V)\)). If given, this is used instead of the dust map value.

Returns:

deredden_flux – Deredden flux values.

Return type:

array