*SUN Section

06MAR26
Type
Optional Section

Description
Name(s) of solar transmittance spectra.

Structure
Multiple fields, same type, any order
FieldTypeDescription
SUNFIL C200 Name of solar transmittance spectrum

Notes
  1. Solar transmittance spectra are used to initialise the transmittance spectrum calculation for instruments which do not automatically calibrate these out with a reference spectrum. These contain absorption lines from simple molecules in the sun's outer atmosphere.

  2. The files are in the RFM Spectral File format (either regular or irregular grid, but only text files, not binary).

  3. One SUNFIL value may include the #MIC token, which will be expanded to include all other microwinows specified in the *MIC section not explicitly included by other SUNFIL values.

  4. Internally only a single solar spectrum is stored. Where multiple files are supplied the spectra are simply merged with the later file replacing any duplicate points in the previous spectrum. Where there are gaps between the input files, or beyond the range of the input files, the spectrum is implicitly assumed to be 1.

Example