October 2009 anneal report for and Cycle 17 Calibration program 11849

There was an anneal of the CCD on October 06, 2009, 28 days after the
previous anneal of September 08, 2009. 

For the most part, past trends continue. The number of post anneal hot
pixels continues to increase. The post-anneal dark now shows 44741 hot
pixels. For this anneal the number of pre-anneal hot pixels was lower
than the previous pre-anneal for all hot pixel levels except for the 10 e/s 
level. The pre-anneal result is 1065 hot pixels and the post-anneal is 
1089 hot pixels. This behavior is seen once in pre-failure data (see Figure 6 
in ISR STIS 2009-01). Two sub-exposures from the post_anneal dark were not 
used due to being SAA impacted. As a result only three of the dark 
sub-exposures were used in the anneal analysis.

1) The *raw* post-anneal dark count rate for this anneal is 0.06925
cnts/pixel for October 2009. This compares with 0.04788 cnts/pixel in 
September 2009 and 0.06643 cnts/pixel in August 2009.

2) The iterated median count rate (after iterating up to 30 times by
eliminating pixels +/- 5*sigma) is 0.01289113 cnts/pixel which is up
from the September's anneal which was 0.00918599 and up from
August's anneal which was 0.01224836. 

3) The creation rates of hot pixels for the last three anneals. 

   August 11, 2009
   > 0.1 e/s: 103.3
   > 1.0 e/s: 14.7
   > 10  e/s: 2.1
   
   September 7, 2009
   > 0.1 e/s: -113.7
   > 1.0 e/s: -39.3
   > 10  e/s: -8.0
 
   October 5, 2009
   > 0.1 e/s: 452.7
   > 1.0 e/s: 85.9
   > 10  e/s: 13.4
   
4) The rate at which new hot pixels are annealed for the last three anneals.

   August 11, 2009
   > 0.1 e/s: 45.6
   > 1.0 e/s: 46.8
   > 10  e/s: 68.4
   
   September 7, 2009
   > 0.1 e/s: -148.7
   > 1.0 e/s: -81.4
   > 10  e/s: -59.4
   
   October 5, 2009
   > 0.1 e/s: 17.2
   > 1.0 e/s: 5.1
   > 10  e/s: -6.6