qac Calibration Q/A Statistics
qac is an ascii file containing the Q/A statistics used by the VMICAL processing stage. Prior to the inclusion of GEOMPIPE into the VMICAL reduction stage, the QA file contained four individual files: qacBAD, qacV, qacM, and qacI. qacBAD contains a label as the first line, followed by a list of "Bad" images which have the header keyword FILLED defined and which should be ignored by processing stages subsequent to VMICAL . The format is the image name followed by ",FILLED = no" (or ",FILLED = yes"). qacV(M,I) contains a label on the first line, followed by two columns of numbers, the first being the GPS time and the second the average velocity (modulation, intensity). The average is computed by average over values of radius from 0 to 95% of maximum radius.
qaz files are bundled into the VMICAL qac files for data from 960801 and after. qaz files are the Quality Assurance parameter files for the GEOMPIPE subsystem of the VMICAL reduction stage. The QA files generated for GEOMPIPE include a list of FILLED images, a file containing the Point Spread Function QA parameters generated by GEOM and culled from the image headers, a file containing the HGEOM QA parameters culled from the image headers, and a file containing the updated image geometry ellipse parameters generated by GEOM and culled from the image headers.
These QA parameters include the following:
CHI2 reduced chi-squared of the least-squares fit performed by HGEOM SLR scattered light ratio LMB_GRAD gradient at the radius that HGEOM determines to be the "limb" C_MA corrected major axis C_MI corrected minor axis EXT_SLOP slope of the sky extension A(1) coefficient of the PSF A(1)_ERR errors of the coefficient A(2) A(2)_ERR A(3) A(3)_ERR FNDLMBXC X center coordinate FNDLMBYC Y center coordinate FNDLMBMI updated minor axis FNDLMBMA updated major axis FNDLMBAN ellipse angle
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