High completeness sub-selection of stellar objects from Source. |
This view of table Source defines a highly complete selection of point sources. The select statement of the view requires the source to be present on at least two out of four plates (Nplates > 1) along with an adequate astrometric fit (ie. chi-squared value < 5.0) and on each plate the following conditions are placed on available morphological parameters: ellipticity < 0.33 (ie. image elongation is less than 50%); -3.0 < profile statistic < 4.5 (ie. the areal profile set of the source is close to an idealised PSF set in terms of a 3sigma lower limit and +4.5 upper limit on the N(0,1) profile statistic); quality flag < 2048 (ie. strong warnings concerning quality issues reject sources from the view). The use of this, or any other, SSA view depends on the particular science application. If your science application needs a high completeness selection of stellar objects but can cope with some contamination (particularly misclassified sources, poorly parameterised deblends at the faint end and poorly parameterised/calibrated images in very crowded regions) then use this view. |
SELECT *
FROM Source
WHERE chi2 < 5.0 AND
Nplates > 1 AND
ellipB < 0.3333333 AND qualB < 2048 AND
((prfstatB > -3.0 AND prfstatB < +4.5) OR prfstatB < -0.9e9) AND
ellipR1 < 0.3333333 AND qualR1 < 2048 AND
((prfstatR1 > -3.0 AND prfstatR1 < +4.5) OR prfstatR1 < -0.9e9) AND
ellipR2 < 0.3333333 AND qualR2 < 2048 AND
((prfstatR2 > -3.0 AND prfstatR2 < +4.5) OR prfstatR2 < -0.9e9) AND
ellipI < 0.3333333 AND qualI < 2048 AND
((prfstatI > -3.0 AND prfstatI < +4.5) OR prfstatI < -0.9e9)