Sequencer Site SIRTF IOC Activity c. 2002

The goals of this task are to determine the
thermal anneal frequency for the 70um and 
160um arrays (major goal) and to characterize the
behavior of the arrays between 
anneals (minor goal).  The reason to anneal the
Ga:Ge arrays is that the damage 
caused by cosmic rays accumulates and the
achievable S/N decreases significantly.  
Thermal anneals have been shown to remove the
affects of cosmic ray damage and 
"reset" the arrays.  The default anneal frequency
for both arrays is 3 hours.  As it is not 
possible to accurately simulate the environment
SIRTF will be in after launch, the 
actual desired anneal frequency is likely to be
different from the default.  The desired 
anneal frequency is also likely to be different
between the 70um and 160um arrays.

In order to determine the desired anneal
frequencies, we will take data to evaluate 
the performance of both arrays for a period of 6
hours.  At the start of this task, both 
arrays will be thermally annealed.  For the next 6
hours, we will take data to evaluate
the read noise, dark current, stim repeatability,
and responsivity for both arrays.  
Taking other data with the 70um or 160um arrays is
unlikely to be desirable during 
this task.  Taking 24um data during this task is
possible, but with the caveat that when 
the 160um stim is flashed, the 24um arrays sees
this stim.

Conditions