Contact Stansberry - "; echo " there is a problem w/ your write-up.\n"; return ; } $row = mysql_fetch_array($result); $title = $row["title"]; $princ = $row["principal"]; $deputy= $row["deputy"]; $campn0 = $row["campn0"]; $aorkeys = $row["aorkeys"]; // get real name of principal, deputies $princ = ioc_get_person($princ); $princ = $princ[0]; $deps = explode(",",$deputy); foreach ($deps as $depty) { $depty = trim($depty); $depty = ioc_get_person($depty); $depty = $depty[0]; $depty = explode(",",$depty); $depty = $depty[0]; // last names only $deplist[] = $depty; } $deplist = implode(", ", $deplist); $caid = sprintf("%03d",$caid); $file = "mips-".$caid.$campn.".analysis.php"; // END PHP. ?> <? echo "MIPS-$caid, Campaign $campn IOC/SV Analysis"; ?>

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Task Outcome Summary


Abstract

The D2 execution of this task used an outdated IER which resulted in an incomplete data set. Because of this, the comparison between RAW and SUR exposures was done for only 4 second exposure times and a non-optimal stim setting. Despite these problems, the data set shows that the SUR data compression algorithm works as determined by ground testing. The first DCE commanded in an exposure sequence (DCE0) continues to produce a lower on-board slope value than fitting of a comparable RAW ramp.

Analysis

Twenty DCEs were obtained in both the RAW and SUR modes with the 24 micron stimulator set to "24FLD" "LOW". The CSMM was positioned at the 24 micron dark position, which eliminated all but a few DN/sample-time from scattered light at the 31 K temperatures of D2. The RAW data were processed using the SUR processing emulation software "sursimslope" written by Frank Masci. This software was compared against the DAT slope fitting algorithm written by James Muzerolle and was found to produce virtually the same result. These algorithms emulate the on-board SUR processor by making a linear, least-squares fit to the samples in the RAW ramp after discarding the specified number of "ignore frames" at the beginning of the exposure. The "ignore frames" parameter is a patchable constant. There is a different "ignore frames" parameter for the first DCE in a commanded exposure sequence (DCE0) and all subsequent DCEs produced by a single CEMIPSUR command. The "sursimslope" program was run using ignore frame = 3 for DCE0 and ignore frames = 1 for all subsequent DCEs. The simulated SUR images were compared with actual SUR images of the same exposure time and commanded order. The comparison utilized the IDL "dostats" program written by Susan Stolovy.

Results

A table of the comparison between slopes derived from 4 second RAW and SUR images of the 24FLD_LOW stim is below: DCE AORKEY.EXPID.DCENUM Plane Mean Median Min Max EXPTIME 0 6763264.0.0 0 1093.32 884.000 0 5780 2.62000 1 6763264.1.0 0 1193.56 965.500 -6.10352e-11 5148.00 2.62000 2 6763264.0.1 0 1176.03 953.000 0 5210 3.67000 3 6763264.1.1 0 1199.37 971.714 -4.76837e-12 5181.00 3.67000 4 6763264.0.2 0 1194.84 968.000 0 5280 3.67000 5 6763264.1.2 0 1203.08 975.071 -4.76837e-12 5212.86 3.67000 6 6763264.0.3 0 1199.50 972.000 0 5244 3.67000 7 6763264.1.3 0 1204.63 976.536 -4.76837e-12 5256.82 3.67000 8 6763264.0.4 0 1201.76 973.000 0 5254 3.67000 9 6763264.1.4 0 1205.57 976.143 -4.76837e-12 5225.96 3.67000 10 6763264.0.5 0 1203.17 974.000 0 5291 3.67000 11 6763264.1.5 0 1206.39 977.464 -4.76837e-12 5285.93 3.67000 12 6763264.0.6 0 1204.19 976.000 0 5232 3.67000 13 6763264.1.6 0 1206.54 978.321 -4.76837e-12 5241.96 3.67000 14 6763264.0.7 0 1204.35 975.000 0 5271 3.67000 15 6763264.1.7 0 1207.01 977.357 -4.76837e-12 5234.36 3.67000 16 6763264.0.8 0 1205.33 976.000 0 5281 3.67000 17 6763264.1.8 0 1206.67 977.929 -4.76837e-12 5207.46 3.67000 18 6763264.0.9 0 1205.53 977.000 0 5241 3.67000 19 6763264.1.9 0 1207.08 978.286 -4.76837e-12 5254.54 3.67000 20 6763264.0.10 0 1205.52 977.000 0 5272 3.67000 21 6763264.1.10 0 1206.82 978.357 -4.76837e-12 5254.64 3.67000 22 6763264.0.11 0 1206.25 977.000 0 5295 3.67000 23 6763264.1.11 0 1207.14 978.357 -4.76837e-12 5237.18 3.67000 24 6763264.0.12 0 1206.23 977.000 0 5255 3.67000 25 6763264.1.12 0 1207.44 978.429 -4.76837e-12 5285.68 3.67000 26 6763264.0.13 0 1206.68 978.000 0 5288 3.67000 27 6763264.1.13 0 1207.32 978.321 -4.76837e-12 5299.36 3.67000 28 6763264.0.14 0 1206.64 977.000 0 5228 3.67000 29 6763264.1.14 0 1207.86 978.857 -4.76837e-12 5304.93 3.67000 30 6763264.0.15 0 1206.90 978.000 0 5214 3.67000 31 6763264.1.15 0 1207.37 978.929 -4.76837e-12 5274.11 3.67000 32 6763264.0.16 0 1207.07 978.000 0 5248 3.67000 33 6763264.1.16 0 1207.28 978.643 -4.76837e-12 5241.36 3.67000 34 6763264.0.17 0 1207.06 978.000 0 5228 3.67000 35 6763264.1.17 0 1208.13 978.786 -4.76837e-12 5269.50 3.67000 36 6763264.0.18 0 1207.00 978.000 0 5200 3.67000 37 6763264.1.18 0 1207.35 977.929 -4.76837e-12 5250.93 3.67000 38 6763264.0.19 0 1207.55 978.000 0 5218 3.67000 39 6763264.1.19 0 1207.75 979.393 -4.76837e-12 5270.68 3.67000 For DCE0, there is a large (9%) disparity between the predicted median slope in DN/sample-time derived from the RAW DCE and the actual SUR slope. Subsequent DCEs rapidly converge on extremely similar values for the RAW and SUR slopes. The DCE1 SUR slope is low by 2%, DCE2 is low by 0.7%, and by DCE5, the values differ by less than 0.3%. The results found in campaign D2 are very similar to the results obtained by an identical analysis of the LF1 ground test (9/14/02). The table of results for that test (which used the identical stimulator setting) is below: DCE AORKEY.EXPID.DCENUM Plane Mean Median Min Max EXPTIME 0 12032.0.0 0 1085.15 868.000 0 6363 3.15000 1 12032.1.0 0 1236.73 998.500 87.0857 9362.14 3.15000 2 12032.0.1 0 1194.96 963.000 0 5633 4.19000 3 12032.1.1 0 1218.40 983.286 -4.76837e-12 5702.00 4.19000 4 12032.0.2 0 1211.57 976.000 0 5618 4.19000 5 12032.1.2 0 1221.35 985.679 -4.76837e-12 5670.21 4.19000 6 12032.0.3 0 1215.64 980.000 0 5619 4.19000 7 12032.1.3 0 1222.62 986.321 -4.76837e-12 5695.00 4.19000 8 12032.0.4 0 1217.95 982.000 0 5585 4.19000 9 12032.1.4 0 1223.22 987.393 -4.76837e-12 5730.21 4.19000 10 12032.0.5 0 1219.39 983.000 0 5641 4.19000 11 12032.1.5 0 1223.50 987.964 -4.76837e-12 5706.93 4.19000 12 12032.0.6 0 1220.47 983.000 0 5603 4.19000 13 12032.1.6 0 1223.97 987.679 -4.76837e-12 5777.71 4.19000 14 12032.0.7 0 1221.21 984.000 0 5596 4.19000 15 12032.1.7 0 1224.10 988.214 -4.76837e-12 5705.18 4.19000 16 12032.0.8 0 1221.94 985.000 0 5572 4.19000 17 12032.1.8 0 1224.15 988.250 -4.76837e-12 5751.36 4.19000 18 12032.0.9 0 1222.41 985.000 0 5653 4.19000 19 12032.1.9 0 1224.40 987.857 -4.76837e-12 5732.11 4.19000 20 12032.0.10 0 1222.99 986.000 0 5634 4.19000 21 12032.1.10 0 1224.39 988.607 -4.76837e-12 5713.61 4.19000 22 12032.0.11 0 1223.39 986.000 0 5625 4.19000 23 12032.1.11 0 1224.58 988.821 -4.76837e-12 5704.29 4.19000 24 12032.0.12 0 1223.72 987.000 0 5613 4.19000 25 12032.1.12 0 1224.66 988.679 -4.76837e-12 5746.82 4.19000 26 12032.0.13 0 1224.05 987.000 0 5643 4.19000 27 12032.1.13 0 1224.48 988.571 -4.76837e-12 5673.46 4.19000 28 12032.0.14 0 1224.13 987.000 0 5638 4.19000 29 12032.1.14 0 1224.60 988.357 -4.76837e-12 5735.46 4.19000 30 12032.0.15 0 1224.44 987.000 0 5683 4.19000 31 12032.1.15 0 1224.71 989.107 -4.76837e-12 5716.25 4.19000 32 12032.0.16 0 1224.53 988.000 0 5651 4.19000 33 12032.1.16 0 1224.57 989.214 -4.76837e-12 5718.68 4.19000 34 12032.0.17 0 1224.68 988.000 0 5640 4.19000 35 12032.1.17 0 1224.65 989.429 -4.76837e-12 5718.32 4.19000 36 12032.0.18 0 1224.79 988.000 0 5628 4.19000 37 12032.1.18 0 1224.67 988.643 -4.76837e-12 5759.46 4.19000 38 12032.0.19 0 1224.91 988.000 0 5706 4.19000 39 12032.1.19 0 1224.54 989.250 -4.76837e-12 5761.54 4.19000 Note that the exposure times appear different because of an error in the 9/02 version of the pipeline TRANHEAD module. In this test, the DCE0 SUR slope is lower than the derived RAW slope by 15%. The differences between the subsequent DCE RAW and SUR slopes is very similar to the on-orbit data. Thus, we have demonstrated that for 4 second exposures, the on-board SUR algorithm produces results very similar to ground testing. For DCE0, the on-orbit SUR results are better than the ground results (although we are only comparing 2 DCEs). Excluding the first DCE taken in an exposure sequence, the SUR algorithm produces slopes within 1% of slopes derived from RAW DCEs.

Conclusions

For the first DCE commanded by each exposure sequence (single execution of CEMIPSUR), the slope produced by the on-board SUR algorithm is systematically 9% lower than slopes fit to comparable RAW mode data. This effect was seen (at an even worse level) in ground testing. For other DCEs, the SUR algorithm produces slopes for unsaturated pixels which are within 1% of slopes derived by linear, least-squares fitting of RAW ramps. We conclude that until and if the DCE0 SUR disparity can be calibrated, the first DCE taken by a command sequence should be discarded.

Output and Deliverable Products

None

Actions Following Analysis

The first DCE taken in each exposure sequence (DCE0000) should not be used in deriving important calibration products or scientific results. The IER used for this task in D2 was outdated, resulting in no useful comparison data for 10 second and 30 second exposure times, and a non-optimal stimulator setting. The 30 second RAW data would be especially useful for confirming that the 24um nonlinearity has not changed on-orbit. The task should be repeated with an updated IER if there is time in IOC/SV.