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Refraction Study Group (RSG) Charter

Considering that the current standard model developed by Marini and Murray for applying atmospheric propagation delay corrections to SLR observations is believed to be uncertain by up to 1cm in the zenith delay term, and considering that it is tuned to particular wavelengths which do not encompass all the wavelengths which might be used in practice.

  • Assess the adequacy and accuracy of the Marini and Murray model for SLR at the 1 mm level, for all elevations above 15 degrees and all wavelengths from 355 to 1570 nanometers and perhaps beyond.
  • If necessary, define a new model and/or set of procedures which will satisfy these requirements, and verify it experimentally.
  • Define optimum schemes for the collection and pre-processing of meteorological and any other necessary data to be used as input to the models/procedures, and assess the impact of the absence of any such data which may be difficult or expensive to collect.
  • Prepare a formal recommendation to the ILRS, including a standard algorithm and set of recommended practices, for adoption by stations and analysis centers.