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AIPS HELP file for SPECINDX in 31DEC22

#### As of Sat Mar 25 1:54:14 2023

### HELP SECTION

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:
BLCHN.....Compute closure offset corrections on a channel-by-channel
basis. SPECINDX is used to remove a slope from the derived
spectrum of baseline corrections.
BPASS.....Computes spectral bandpass correction table.
SPECINDX is used to remove a slope from the derived
bandpass amplitude spectrum.
CPASS.....Computes polynomial spectral bandpass correction table.
SPECINDX is used to remove a slope from the derived
bandpass amplitude spectrum.
EVAUV.....Subtracts & divides a model into UV data, does statistics on
results. SPECINDX is the spectral index used with SMODEL.
SETJY.....Task to enter source info into source (SU) table. SPECINDX
is the spectral index to be used with ZEROSP and SPECURVE.
SOUSP.....Fits SPECINDX and SPECURVE to the fluxes in an SU table
returning the values for input to BPASS.

### EXPLAIN SECTION