MDM Trouble Report for 2005 Mar 9

Telescope: 2.4m
Observer(s): Basu-Zych (Columbia U.)
Instrument: MKIII

Problem(s) Encountered:
The CCD overheated noticibly around 12:30am (the dewar was filled recently, at 6:30pm).
I noticed the overheating suddenly in my observations when the signal from my 
source was no longer distinguishable from the noise (which was ~ 6000 counts for
a 30 min exposure). The 30 min exposure following this incident had noise 
>20000 counts. By typing 'ut' in ccdcom I realized the ccd temp was too high:-22.0. 
I took a couple of biases to find that the noise increased linearly in the y-direction.
I made the accident of refilling the dewar in hopes of cooling the ccd back down
(I only read the note about NOT doing this after I had already done so). In any
case, it made little difference, the temp fell a bit only to rise sharply after. The CCD 
temperature rose at a rate of about 0.3 degrees C per minute. I shut everything down
by 2:30 and tried instead to pinpoint the time and cause of the problem and found
no answer.

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Submitted on 2005 Mar 9 [4:54:30]