Analysis of startup, shutdown and middle sequences, Campaign 24 Abstract: The results are similar to previous campaigns, with the exception of the first middle anneal sequence, when all SURN measurements exceeded the limits and previous averages. All SRSRN data are fine, and of the remaining SURN tests, SL values hovered near the 8.8 DN limit, LH exceeded its 17.6 DN limit every time, but with noise levels comparable to previous campaigns, and the other models performed within specifications. The Solar flare event which began late on 7 September and ran into 12 September affected many of our results, but only one anneal sequence which took place on 8 September showed significantly higher noise levels. From this, we conclude that the IRS read noise is only sensitive to protons with energies higher than 100 MeV. Analysts: Lei Hao & Greg Sloan Procedure version: 2.7 Campaign 24, Startup, shutdown and middle anneal YEAR 2005 DOY 248 CE1 used for all data collection AORKEY = 15866624 for startup AORKEY = 15878912 for the first mid-campaign anneal sequence AORKEY = 15879168 for the second mid-campaign anneal sequence AORKEY = 15869440 for shutdown Number of files = 64 for each No known errors. Steps 2 through 5 run OK. Unruly.pro results for startup (IRS-001): Noise characteristics of the modules (in DN) SUR data SRS data noise pre post noise pre post Module limit anneal anneal limit anneal anneal SL 8.8 8.4 9.1 15.0 12.3 12.1 SH 8.8 7.0 6.9 15.0 12.9 12.7 LL 14.5 12.8 13.8 15.0 13.0 13.0 LH 17.6 19.5 19.6 15.0 13.2 13.2 Unruly.pro results for the first middle (IRS-002a): Noise characteristics of the modules (in DN) SUR data SRS data noise pre post noise pre post Module limit anneal anneal limit anneal anneal SL 8.8 11.9 16.6 15.0 13.7 13.6 SH 8.8 11.8 10.6 15.0 13.9 14.3 LL 14.5 18.7 19.6 15.0 13.6 13.9 LH 17.6 25.1 25.7 15.0 14.2 13.9 Unruly.pro results for the second middle (IRS-002b): Noise characteristics of the modules (in DN) SUR data SRS data noise pre post noise pre post Module limit anneal anneal limit anneal anneal SL 8.8 8.3 9.1 15.0 12.3 12.1 SH 8.8 6.8 7.1 15.0 12.9 12.9 LL 14.5 15.1 11.3 15.0 13.1 13.0 LH 17.6 19.1 19.4 15.0 13.2 13.3 Unruly.pro results for shutdown (IRS-003): Noise characteristics of the modules (in DN) SUR data SRS data noise pre post noise pre post Module limit anneal anneal limit anneal anneal SL 8.8 8.0 8.6 15.0 12.2 12.2 SH 8.8 7.0 7.1 15.0 12.8 12.8 LL 14.5 12.8 12.0 15.0 12.9 12.8 LH 17.6 21.2 19.4 15.0 13.3 13.3 The analysis applied the PIRAT procedure unruly.pro to FITS files generated by MIPL. For SUR data, the quoted values are the standard deviation of the read noise map. For SRS data, these are the median of the standard deviation map. Comments: The SRS tests are all within limits, even though the first middle campaign has slighly higher SRS noise than others. The SURN results are much like previous campaigns, except that the first middle anneal sequence was badly affected by a Solar flare event. Of the remaining six measurements, SL exceeded its limit twice, SH and LL stayed within their limits, and LH exceeded its limit every time, with noise values between 19 and 21 DN. These results for LH are typical. The behavior in the first and second middle anneal sequences provides some useful limits to the sensitivity of the noise in the system to flare-induced photons. The first middle anneal sequence took place at 1611 8 Sep 05, and the second at 1600 11 Sep 05 (UT). Proton counts were up at all levels on 8 Sep, but on 11 Sep, protons greater than 100 MeV had dropped from about 3 (cm^-2 s^-1 sr^-1) to 0.3, while protons greater than 10 MeV had risen (from 30 to 300) and protons greater than 50 MeV had only dropped slightly (from about 8 to 5). Thus, we conclude that the IRS read noise is really only sensitive to impacts from 100 MeV protons or greater. Changes in read noise between anneals and from startup to shutdown (using both mid-campaign seqeunce, IRS-002a, and IRS_002b): SUR data SRS data 002a-pre/ 003-pre/ 003-pre/ 002a-pre/ 003-pre/ 003-pre/ Module 001-post 002a-post 001-post 001-post 002a-post 001-post SL 1.32 0.49 0.89 1.13 0.90 1.01 SH 1.70 0.66 1.01 1.09 0.89 1.00 LL 1.35 0.65 0.92 1.05 0.93 1.00 LH 1.28 0.82 1.08 1.08 0.96 1.01 SUR data SRS data 002b-pre/ 003-pre/ 003-pre/ 002b-pre/ 003-pre/ 003-pre/ Module 001-post 002b-post 001-post 001-post 002b-post 001-post SL 0.92 0.88 0.89 1.01 1.01 1.01 SH 0.99 0.99 1.01 1.01 0.99 1.00 LL 1.09 1.13 0.92 1.01 0.99 1.00 LH 0.97 1.09 1.08 1.00 1.00 1.01 Comments: Because of the storm, noise comparisons involving the first middle campaign are very bad. Even the SRS results are affected, reaching values of 13% compared to the typical 1-2% Variation in SURN is up to 70%. Using the second middle anneal sequence instead of the first produces more reasonable results. Only in the case of LL do we see variations above the yellow limit, and nowhere do we exceed the red limit. Photoresponse stability (using the first middle IRS_002a): Module 002a-pre to 001-post 003-pre to 002a-post 003-pre to 001-post yellow red yellow red yellow red SL 3515 207 70 0 46 0 SH 0 0 0 0 0 0 LL 6759 1244 4000 5 4125 5 LH 5860 1174 17 4 20 4 Comments: SH was stable throughout the campaign. The Solar flare event has affected the results early in the campaign, but after that, the arrays seem to be well behaved. The SL1 slit is visible in the comparisons of 003-pre to 002a-post and 003-pre to 001-post. There are several latent images in the Peak-up field in SL, pushing 46-70 pixels over the yellow limit. The orders in LL orders are also clearly visible and very bright, forcing over 4000 pixels over the limit. The LH orders are also visible, though not very bright. For the comparison of 002a-pre to 001-post, the SL PU image is even worse, with more latent images and two widely extended bright regions. SL1 is again visible, though weak compared to the PU latent images. In LL the orders are again clearly visible. This is also true for LH. Pixels over Red Limit: LL: (52,4) (76,13) (64,27) (76,64 (47,105) LH: (15,74) (123,82) (8,84) (84,114)