Analysis of startup and shutdown sequences, Campaign 2

Abstract:  All SRSRN results are within the limits, but the SL SURN 
values after the startup anneal, after the mid-campaign anneal, and 
before the shutdown anneal were all over the 8.8 DN limit (at 9.0, 
9.4, and 9.1 DN respectively).  After the shutdown anneal, LH had 
SURN values at 17.7 DN (limit 17.6 DN).  Other than those excesses, 
all data were within SURN specifications.  In both halves of the 
campaign, the SUR read noise dropped by 10% or more between anneals.
Similarly, the LH SRSRN changed 2% in each half of the campaign,
leadingn to a cumulative shift of 4%.  While larger than any change
in SRSRN seen so far, this is still within the 5% yellow limit.
In both LL and LH, two pixels showed a change in photoresponse over
the 5% limit.

Analysts:  Greg Sloan
Procedure version:  2.7
Campaign 1, Startup
YEAR 2004 DOY 003
CE1 used for all data collection
AORKEY = 8546304 for startup
AORKEY = 8545792 for the mid-campaign anneal sequence
AORKEY = 8546048 for shutdown (but the AOR had no name)
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     8.0     9.0    15.0    12.0    12.1 
    SH       8.8     6.9     7.2    15.0    12.5    12.7 
    LL      14.5    10.5    12.4    15.0    12.7    12.6 
    LH      17.6    15.7    17.0    15.0    12.7    12.8 

Unruly.pro results for middle (IRS-002):

    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     7.9     9.4    15.0    12.3    12.3 
    SH       8.8     6.5     7.1    15.0    12.7    12.8 
    LL      14.5    12.5    12.0    15.0    12.9    12.9 
    LH      17.6    17.0    17.1    15.0    13.1    13.1 

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     9.1     8.6    15.0    12.0    12.3
    SH       8.8     6.2     7.1    15.0    12.8    12.7
    LL      14.5    12.2    10.3    15.0    13.1    12.9
    LH      17.6    17.4    17.7    15.0    13.0    13.0
                                                                                
    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:  All SRSRN data are within limits in both startup 
    and shutdown.  The SURN data are slightly more problematic,
    with SL over the 8.8 DN limit after the startup anneal and
    before the shutdown anneal, and LH over the 17.6 DN limit
    after the shutdown anneal.

Changes in read noise between anneals and from startup to shutdown:

            SUR data                       SRS data
            002pre/   003pre/    003pre/   002pre/   003pre/    003pre/
    Module  001post   002post    001post   001post   002post    001post

    SL      1.01      0.97       1.01      1.02      0.98       1.01
    SH      0.90      0.87       0.86      1.00      1.00       1.01
    LL      1.01      1.02       0.98      1.02      1.02       1.04
    LH      1.00      1.02       1.02      1.02      0.99       1.02

    Comments:  Given the length of this campaign compared to IOC/SV
    activities, the stability remains quite good.  There are two
    issues, though.  First, the SH SURN varied by 14% during the 
    campaign, and second, The LL SRSRN varied by 4%, the largest
    variation in SRSRN seen so far, although the variation in each 
    half of the campaign was only 2%.  

Photoresponse stability:

    Module  002 pre to 001 post  003 pre to 002 post  003 pre to 001 post
            yellow  red          yellow  red          yellow  red
    SL        0       0            0       0            0       0
    SH        0       0            0       0            0       0
    LL        0       0            1       0            2       0
    LH        1       0            2       0            2       0

    No pixel exceeds the red limit after flagging dead and warm pixels.
    Two LL pixels exceeded the yellow limit.  Pixel 23,119 dropped in
    sensitivity in the second half of the campaign, and pixel 46,78
    increased in senstivity when comparing the beginning and end of
    the campaign.  Two LH pixels also exceeded the yellow limit.
    Pixel 0,65 showed decreasing sensitivity in all three comparisons,
    and pixel 5,122 dropped in sensitivity when comparing IRS-003 to
    either of the previous anneal sequences.