MIPS_261a Read Noise #2


IOC-MIPS_261a     10520C,10540C,10570C              
Title:   MIPS Read Noise and Dark Current and Stability of Read Noise and Dark Current                
    Second Measurement                
Objective:   Measure the read noise in each MIPS mode and check its stability over a week timescale.                
    The dark current will be measured using the same data set.                
                     
Description:     For each array, the scan mirror must be moved to the dark position before beginning the test.              
including flow / state diagram     The entire pattern should be repeated one day and one week after the initial test.              
      This template is the second execution of the test and should occur 1 day after the first.              
    Part 1: 1) Read noise test on the 24um array:              
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        100 repeats of the 30-second mode.            
    Part 2: 2) Read noise test on the 70um array:              
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Wait 2 hrs (other observing including programs using this array can occur).            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
      100 repeats of the 10-second mode.            
        Wait 4hrs (other observing can again proceed).            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Switch scan mirror to other 70um dark position.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
    Part 3: 3) Read noise test on the 160um array.              
        Perform a thermal anneal on the array.            
      100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Wait 2 hrs (other observing including programs using this array can occur).            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Wait 4hrs (other observing can again proceed).            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
        Perform a thermal anneal on the array.            
        100 repeats of the 3-second mode.            
        100 repeats of the 10-second mode.            
                     
Place in Schedule:                  
(relative to water shed events)     CTA and instrument must be at 5.5K.              
                     
Required Conditions:   Telescope must be pointed at a low sky background region as judged from IRAS data (if              
      the scattered light test as a function of telescope temperature indicates that MIPS is extremely dark,              
      then this requirement as well as the telescope temp. req. could be relaxed.)              
      This test should occur after the detector bias test and after the detector operating temperature test.              
      This test should occurr one day after the first read noise stability test.              
Resources:                    
                     
  duration (best estimate)         9hrs      
  real time downlink (Y / N)         No        
  special post event actions (Y / N)         No        
  Generates 3900 DCEs.                  
                     
Outcome:                    
  description         The lowest possible dark current will be known along with stability and anneal patterns.        
  can proceed in parallel with other activity         Yes, if pointing at low sky background areas        
  must outcome be confirmed before next event / test /activity         No        
  method of confirmation (sensor TLM, data analysis, etc.)         data analysis        
  estimate of data turn around if required for confirmation         N/A        
                     
Unique or included in planned AOT?                    
      Use the IER planned for anneals and darks.              
                     
Contingency Plan:                    
"What if..."     Only contingency here would involve repeating the test to explore more anneal timings.              
                     
IOC Critical     Y              
                     
References:                    
                     
Template last updated:     9/7/99              
      M. Rieke              
                     


Last Updated on 10/7/99
By Marcia Rieke
Email: mrieke@as.arizona.edu