vac_to_air¶
- specutils.utils.wcs_utils.vac_to_air(wavelength, method='Morton2000', co2=None)[source]¶
Converts vacuum to air wavelengths using different methods.
- Parameters:
- wavelength
Quantity
object (number or sequence) Vacuum wavelengths with an astropy.unit.
- methodstr, optional
One of the methods in refraction_index(), default is ‘Morton2000’.
- co2number, optional
Atmospheric CO2 concentration in ppm. Only used for method=’Ciddor1996’. If not given, a default concentration of 450 ppm is used.
- wavelength
- Returns:
- air_wavelength
Quantity
object (number or sequence) Air wavelengths with the same unit as wavelength.
- air_wavelength