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January 2002 anneal report for program 8841.

There was an anneal of the CCD on Jan 9, 2002, 25 days after the previous
anneal on Dec 15, 2001.  A homogeneous set of data was obtained from proposal
8841:  The CCD Hot Pixel Annealing.

Previous trends continue.  The growth rate of hot pixels continues within the
range seen for previous months.

1) The number of post-anneal hot pixels has decreased or remained constant at
   all three levels.

   > 0.1 e/s: 15800 pixels on Jan 9, 2002
   > 1.0 e/s:  3295
   > 10. e/s:   353
   
   > 0.1 e/s: 15801 pixels on Dec 15, 2001
   > 1.0 e/s:  3340
   > 10. e/s:   387
   
   > 0.1 e/s: 15839 pixels on Nov 19, 2001
   > 1.0 e/s:  3250
   > 10. e/s:   346
   
   > 0.1 e/s: 15589 pixels on Oct 19, 2001
   > 1.0 e/s:  3266
   > 10. e/s:   365


2) The *raw* post-anneal dark countrate for this anneal is 0.02451 cts/pixel.
   This compares with 0.02550 cts/pixel a month ago, and 0.02481 cts/pixel 
   a year ago.
   
3) The iterated median count rate (after iterating up to 30 times by
   eliminating pixels +/- 5*sigma) is 0.00416, down from last month.

4) The creation rates for hot pixels over this period were within the normal
   range of fluctuations.

   > 0.1 e/s:  48.1 pixels/day in Jan 2002
   > 1.0 e/s:   3.7
   > 10  e/s:   0.0

   > 0.1 e/s:  31.0 pixels/day in Dec 2001
   > 1.0 e/s:   7.8
   > 10  e/s:   2.3

   > 0.1 e/s:  10.6 pixels/day in Nov 2001
   > 1.0 e/s:   2.5
   > 10  e/s:   0.0


   > 0.1 e/s:  41.3 pixels/day 1 year ago
   > 1.0 e/s:   5.3
   > 10  e/s:   0.8


5) The rate at which new hot pixels annealed out was within the normal range of
   fluctuations.

   > 0.1 e/s: 100.1% annealed away in the Jan 9, 2002 anneal
   > 1.0 e/s: 151.1%
   > 10  e/s:     0%
   
   > 0.1 e/s: 104.9% annealed away in the Dec 15, 2001 anneal
   > 1.0 e/s:  53.8%
   > 10  e/s:    28%
   
   > 0.1 e/s:  21.4% annealed away in the Nov 19, 2001 anneal
   > 1.0 e/s: 121.1%
   > 10  e/s:  2000%


   The usual plots are attached.

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