SHORT_SD_FACTOR

    REAL multiplicative calibration factor; it is used to convert from the  sin-
    gle dish map units (e.g., main-beam brightness temperature) to janskys.

    A  default  value  of  0 can be used if the original data file is in unit of
    Tmb, the main beam brightness temperature, because in this case the  conver-
    sion  factor can be derived from the beam size. UV_SHORT will complain if it
    cannot derive the appropriate value.