INNAME Input UV file name (name) INCLASS Input UV file name (class) INSEQ 0.0 9999.0 Input UV file name (seq. #) INDISK 0.0 9.0 Input UV file disk unit # SRCNAME Source name CALCODE Calibrator code QUAL -1.0 Source qualifier -1 => any DOCLIP > 0 allows the task to clip bad values at DOCLIP * rms ORDER Order of fit REFREQ Reference frequency in GHz < 0 -> header, 0 -> 1 GHz NOISE Noise in Jy for each freq 0 => 0.1 initially 0 => rms on the plots FLDSIZE (Flux, freq) in (Jy, GHz) 0 => use source table DOCONFRM -1.0 1.0 > 0 => replace SU table values with fit SNVER -1.0 > 0 -> also correct SN table INVERS -1.0 > 0 -> correct SNVER-INVERS SYMBOL 0.0 24.0 Symbol to use on plot FACTOR 0.0 20.0 Scale plot symbols PIXRANGE Control the Y plot range DOTV > 0 => plot on TV, 0 no plots < 0 => make 2 plot files GRCHAN 0.0 7.0 TV graphics channel to use SPECFLUX @ Flux at REFREQ SPECINDX @ Spectral index SPECURVE @ Spectral index curvature

SOUSP Task: This task fits fluxes for a source to determine the spectral index and spectral index curvature: log10 (flux) = A + SPECINDX * log10(f/f0) + SPECURVE(1) * [log10(f/f0)]^2 + ... where A is log10 of the flux at REFREQ, f is the frequency, and f0 is REFREQ. It then plots the fit in both log and linear space on the TV or in plot files. It will return the adverbs SPECINDX and SPECURVE for use in other tasks such as BPASS. Adverbs: INNAME.....Input UV file name (name). Standard defaults. INCLASS....Input UV file name (class). Standard defaults. INSEQ......Input UV file name (seq. #). 0 => highest. INDISK.....Disk drive # of input UV file. 0 => any. SRCNAME....Name of source ' ' not allowed CALCODE....SOURCES(1) may occur more than once in the source table with different calibator codes. CALCODE may then be used to select which one you want. ' ' => any calibrator code selected '* ' => any non blank code (cal. only) '-CAL' => blank codes only (no calibrators) anything else = calibrator code to select. NB: The CALCODE test is applied in addition to the other tests, i.e. SOURCES(1) and QUAL, in the selection of the source for which to determine the solution. QUAL.......Source qualifier: -1 => any, 0 is a real value. DOCLIP.....> 0 -> examine fluxes(if) and drop any more than DOCLIP(1) times the rms away from the median, all evaluated in log10(flux(if)), 0 < DOCLIP <= 1 -> 5. ORDER......<= 1 => fit spectral index only, 2 also fit SPECURVE(1), 3 also fit SPECURVE(2), 4 also fit SPECURVE(3). You will normally not wish to use more than 2. REFREQ.....Compute total flux, spectra index and curvature with reference frequency REFREQ in GHz 0 => use 1 GHz; < 0 => use header frequency If FLDSIZE is used, REFREQ is set to 1 GHz. NOISE......Noise value for frequencies 1 up to 64. If FLDSIZE is not used, then these apply to the fluxes in the SU table for the named source. Otherwise, they apply to the fluxes and frequencies listed in FLDSIZE. 0 -> 0.1 Jy for the weighting used in fitting The error bars in the plots use NOISE(i), if > 0, and the actual rms otherwise. FLDSIZE....FLDSIZE(1,i) is the flux for the i'th frequency to be fit in Jy and FLDSIZE(2,i) is the frequency in GHz. The number of frequencies to be fit is determined by the number of FLDSIZE pairs that are both > 0. If all are 0, then the SU table is used to provide the fluxes for the various IF frequencies. DOCONFRM...> 0 => ask after plotting if the SU table values should be replaced by the fit values - a YES or yes answer must be given to make this happen. This is only done if all of FLDSIZE is 0. <= 0 => do not change the fluxes in the SU table and do not ask about it. SNVER......If > 0 and DOCONFRM > 0 and all of FLDSIZE is 0, then correct SN table version SNVER for new fluxes (if any). INVERS.....If > SNVER > 0, correct SN table versions SNVER through INVERS for new fluxes (if any). SYMBOL.....Choices are 1: Plus sign 13: Star of David 2: Cross (X) 14: Seven-pointed star 3: Circle 15: Eight-pointed star 4: Box 16: Nine-pointed star 5: Triangle 17: Ten-pointed star 6: Diamond 18: 11-pointed star 7: Pentagon 19: 12-pointed star 8: Hexagon 20: 13-pointed star 9: Septagon 21: 14-pointed star 10: Octagon 22: Plus (+) with gap 11: Nine-gon 23: Cross (X) with gap 12: Five pointed star 24: Vertical line FACTOR.....Scale plot symbols by FACTOR 0 -> 1. Data points are plotted as symbols, error bars as vertical lines, and the fit as a connected line. PIXRANGE...If PIXRANGE(2) > PIXRANGE(1), the plot will only cover that range in flux. Otherwise it will cover the full trange of the data (only). DOTV.......> 0 => plot directly on the TV device, otherwise make a plot file for later display on one or more devices (including the TV if desired). GRCHAN.....Graphics channel (1 - 7) to use for line drawing. A value of 0 causes more than one graphics channel to be used. Returned adverbs SPECFLUX...Flux at REFREQ SPECINDX...Spectral index defined above. SPECURVE...Spectral index curvature parameters based on a reference frequency of REFREQ GHz and base-10 logarithms.