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AIPS HELP file for SPECURVE in 31DEC18

#### As of Sat Jun 23 2:20:00 2018

### HELP SECTION

SPECURVE
Type: Adverb (Real array(3))
Use: Spectral index curvature defined so that the flux density goes
as
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.
SPECURVE is used to remove curvature from the derived
bandpass amplitude spectrum. f0 is the frequency in the
UV data set header and is independent of IF and channel.
SOUSP.....Fits SPECINDX and SPECURVE to the fluxes in an SU table
returning the values for input to BPASS.

### EXPLAIN SECTION