Calculate fluxes, FCFs and beam size from a given uncalibrated map of a point source. The results are
written to a log file called log.checkcal if desired.
The images are cropped to the given size (as specified in the FITS headers or via the MAP_HEIGHT
and MAP_WIDTH recipe parameters, whihc must be at least twice the diameter of the
A background may be fitted and removed. (Optional - only if the REMOVE_BACKGROUND recipe
parameter is true.)
The beam size is determined using KAPPA beamfit.
FCFs are calculated from the cropped (background-subtracted) image.
The source flux and its uncertainty are derived from aperture photometry on these images. The
background is estimate from an annulus with inner and outer radii of 1.25 and 2.0 times the aperture
The map is calibrated using either the standard FCF or the one derived above (if the USEFCF recipe
parameter is true).
The noise is calculated from the calibrated map.
The matched filter is applied to the calibrated map.
Results are written to a log file, log.checkcal.
By default this recipe only works on known calibration sources. However, the user may specify
the source flux at 850 and/or 450 um by using recipe parameters called FLUX_850 and
FLUX_450 respectively. The fluxes for different sources may be specified by appending
the target name (in upper case with spaces removed), e.g. FLUX_850.HLTAU. (See also
By default a log file is written containing a variety of information about the data and the values
The following parameters can be set via the -recpars option:
Radius of aperture in arcsec for calculating total flux. The default is 30 arcsec.
Method to use for removing background. May be fitsurface,
findback, plane or dc. Default is fitsurface.
Size of the box (in pixels) used by
findback. Default is 11.
Flag to indicate whether or not to force a Gaussian fit to
the source when estimating the beam parameters. Default is 1 (fit Gaussian).
flag to denote that the amplitude of the fit to the source should be fixed as the peak value
in the map. Default is 0 (amplitude is a free parameter).
background level to be used in the fit to the source. May be ! to allow the background
to float. If not given, the default is either a fixed level of 0 for known calibrators, or the
background is left as a free parameter.
Up to two values which
define either the order of the polynomial (for polynomial) or the number of knots (for
spline) in the X and Y directions respectively. A single number means the same value is
used for both axes. Default is 2 for polynomial, 4 for spline.
Type of fit to use with fitsurface. May be polynomial or spline. Default is polynomial.
A flag to denote whether or not to keep the fitted surface on disk.
Useful for debugging purposes. Default is 0 (do not keep on disk).
density at 450 um in Jy. Source-specific values may be given by dot-appending the source
name in upper case with spaces removed. For example, FLUX_450.DGTAU.
Source flux density at 850 um in Jy. Source-specific values may be given by dot-appending
the source name in upper case with spaces removed (see above).
A flag to
indicate whether or not to keep all files produced by the recipe. May be 0 to keep no files, or
keep only files with suffix _crop, _back and _mf. Default is -1 (keep all files).
denote whether to write results to a log file at the end of processing. Default is 1 (write log file).
Height of map in arcsec after cropping. Must be at least twice the aperture diameter.
Default is that in the FITS header.
Radius in arcsec of the circular region to define
the map. Must be at least twice the aperture radius. Overrides the use of MAP_HEIGHT
Width of map in arcsec after cropping. Must be at
least twice the aperture diameter. Default is that in the FITS header.
Flag to denote whether to mask the source before removing the background. Default is 0
(do not mask the source).
Method used to calculate the noise in the
calibrated image. May be VARIANCE to use the variance, MASK to mask out the source
and calculate the image-plane standard deviation, or MINIMUM to determine the lowest
standard deviation in a series of apertures placed on the image. Default is VARIANCE,
and minimum match is supported.
Name of a file to use as the
PSF when applying the matched filter.
A flag to indicate
whether or not a background should be estimated and removed from the image. Default
is 0 (do not remove a background).
Flag to denote whether to calibrate the
data using the FCFs derived in this recipe (1) or use standard FCFs (0). Standard FCFs
will be used if not specified.
Calibration type to use if USEFCF is
1. May be ARCSEC, BEAM or BEAMMATCH. Default is BEAM.
The log file contains the following entries: 1. Input filename 2. UT date
(YYYY-MM-DDTHH:MM:SS.S) 3. Object name 4. Observation number 5. Wavelength (um) 6. Airmass
7. 225-GHz tau 8. tau at observing wavelength 9. Aperture radius (arcsec) 10. USEFCF flag 11. Flux
within an aperture (pW) 12. Uncertainty in derived flux above (pW) 13. Noise derived from
variance (mJy/beam) 14. Flux conversion factor derived using the integrated flux within an
aperture (Jy/sq arcsec/pW) 15. Uncertainty in above FCF 16. Flux conversion factor derived
from peak of Gaussian fit to source (Jy/beam/pW) 17. Uncertainty in above FCF 18. Flux
conversion factor derived from peak of Gaussian fit to source after processing with a matched
filter (Jy/beam/pW) 19. Uncertainty in above FCF 20. FWHM of main beam (arcsec) 21.
Contribution of error beam (per cent) 22. Flag to indicate whether the beam fit was a Gaussian