; SPECINDX
;---------------------------------------------------------------
;! Spectral index used to correct calibrations
;# ADVERB CALIBRATION SPECTRAL
;-----------------------------------------------------------------------
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;-----------------------------------------------------------------------
;---------------------------------------------------------------
SPECINDX  LLLLLLLLLLLLUUUUUUUUUUUU CCCCCCCCCCCCCCCCCCCCCCCCCCCCC
----------------------------------------------------------------
SPECINDX
Type: Adverb (Real)
Use:  Spectral index defined so that the flux is proportional to
             (frequency) ^ (spectral index)
      In full detail:

            log(T(f)/T(f0) = S * log(f/f0) + C(1) * (log(f/f0))^2
               + C(2) * (log(f/f0))^3 + C(3) * (log(f/f0))^4

      where S is SPECINDEX and C is SPECURVE, f0 is 1 GHz for
      simplicity, and all logs are base 10.  It is unlikely for you to
      have reliable values for SPECURV(3); SETJY uses only through
      SPECURVE(2) for the basic flux calibration sources.
Tasks:
  BPASS.....Computes spectral bandpass correction table.
            SPECINDX is used to remove a slope from the derived
            bandpass amplitude spectrum.
  SOUSP.....Fits SPECINDX and SPECURVE to the fluxes in an SU table
            returning the values for input to BPASS.
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