get_atran¶
- sofia_redux.instruments.fifi_ls.get_atran.get_atran(header, resolution=None, filename=None, get_unsmoothed=False, use_wv=False, atran_dir=None)[source]¶
Retrieve reference atmospheric transmission data.
ATRAN files in the data/atran_files directory should be named according to the altitude, ZA, and wavelengths for which they were generated, as:
atran_[alt]K_[za]deg_[wmin]-[wmax]mum.fits
For example, the file generated for altitude of 41,000 feet, ZA of 45 degrees, and wavelengths between 40 and 300 microns should be named:
atran_41K_45deg_40-300mum.fits
If use_wv is set, files named for the precipitable water vapor values for which they were generated will be used instead, as:
atran_[alt]K_[za]deg_[wv]pwv_[wmin]-[wmax]mum.fits
The procedure is:
Identify ATRAN file by ZA, Altitude, and WV , unless override is provided.
Read ATRAN data from file and smooth to expected spectral resolution.
Return transmission array.
- Parameters:
- headerfits.Header
ATRNFILE keyword is written to the provided FITS header, containing the name of the ATRAN file used.
- resolutionfloat, optional
Spectral resolution to which ATRAN data should be smoothed.
- filenamestr, optional
Atmospheric transmission file to be used. If not provided, a default file will be retrieved from the data/atran_files directory. The file with the closest matching ZA and Altitude to the input data will be used. If override file is provided, it should be a FITS image file containing wavelength and transmission data without smoothing.
- get_unsmoothedbool, optional
If True, return the unsmoothed atran data in addition to the smoothed.
- atran_dirstr, optional
Path to a directory containing ATRAN reference FITS files. If not provided, the default set of files packaged with the pipeline will be used.
- use_wvbool, optional
If set, water vapor values from the header will be used to select the correct ATRAN file.
- Returns:
- numpy.ndarray
Filename of the atmospheric transmission file used and a (2, nw) array containing wavelengths and (optionally smoothed) transmission data.