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Space Telescope Imaging Spectrograph
Phase I: CCD Hot Pixel Annealing

STIS Cycle-18 Calibration Phase-1

Last Revised: August 24, 2010
Proposal ID: 12404
Title: CCD Hot Pixel Annealing
PI: Michael A. Wolfe
Co-I(s): William Van Dyke Dixon, Elena Mason

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# Orbit estimates are TOTAL for all of cycle-18; assume 13 weeks) 
# 01 November 2010 to 31 October 2011

Total Prime Orbits:                  0
External Parallel Orbits:            0
Internals or no-impact orbits:      39
Comments on orbit estimate:   1 anneal will execute every 4th
week using 3 orbits.  


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# This section should be written with a GO audience in mind -- use 
# Calibration plans in WFPC-2 handbook as a guide.

Purpose:         To anneal hot pixels and the effectiveness of the CCD
hot pixel annealing is assessed by measuring the dark current behavior
before and after annealing.
                                      
Description: The CCD Thermoelectric cooler will be turned off to allow
the CCD detector temperature to rise from ~ -80 C to +5 C. The CCD
will be left in the uncooled state for appoximately 12 hours. At the end
of this period the Thermoelectric cooler is turned back on and the CCD
is cooled to its normal operating temperature. Since the CCD on Side-2
does not have thermistor, a 3 hour period, at a minimum, is necessary to
ensure that the CCD is cool and stable
               
Accuracy:                            1%

Comments on Accuracy:     Anneal the CCD and measure the growth rate
of hot pixels
     
Products:  Hot pixel growth rate, median dark count rate, ISR,
reference files


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# THE REST OF THIS FORM IS FOR INTERNAL USE
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# Target information (copy for each target)

Target Name.............................: n/a (internal)	
RA.............................................: n/a 		
Dec...........................................: n/a		
Flux (and units)........................: n/a	
Visibility window (if known or relevant): n/a
Comment on choice of target: n/a

# Table of exposures (copy for each exposure):

Target or lamp..........................: DARK
Type of Acquisition.....................: 
Detector for observation................: STIS/CCD
Operating mode .........................: 
Spectral Element........................:  DEF
Aperture................................:  DEF
Central Wavelength......................:  
Exposure Time...........................: 1200s
Number of Iterations ...................: 3
BOP Predicted Local Count Rate for MAMA.:
BOP Predicted Global Count Rate for MAMA:
ETC PID IDs for Count Rates.............:
Special Requirements or options.........: 
Comments: Take Exposure every 4th week.

Target or lamp..........................: BIAS
Type of Acquisition.....................: 
Detector for observation................: STIS/CCD
Operating mode .........................:  
Spectral Element........................: DEF
Aperture................................: DEF
Central Wavelength......................:  
Exposure Time...........................: 0
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.:
BOP Predicted Global Count Rate for MAMA:
ETC PID IDs for Count Rates.............:
Special Requirements or options.........: 
Comments: Take exposure every 4th week.

Target or lamp..........................: TUNGSTEN
Type of Acquisition.....................: FLAT
Detector for observation................: STIS/CCD
Operating mode .........................: ACCUM
Spectral Element........................: MIRROR
Aperture................................: 50CCD
Central Wavelength......................:  
Exposure Time...........................: 0.6s
Number of Iterations ...................: 3
BOP Predicted Local Count Rate for MAMA.:
BOP Predicted Global Count Rate for MAMA:
ETC PID IDs for Count Rates.............:
Special Requirements or options.........: GAIN=4
Comments: Take exposure every 4th week.

Target or lamp..........................: TUNGSTEN
Type of Acquisition.....................: FLAT
Detector for observation................: STIS/CCD
Operating mode .........................: ACCUM
Spectral Element........................: G750M
Aperture................................: 52X2
Central Wavelength......................: 6768  
Exposure Time...........................: 0.1s
Number of Iterations ...................: 3
BOP Predicted Local Count Rate for MAMA.:
BOP Predicted Global Count Rate for MAMA:
ETC PID IDs for Count Rates.............:
Special Requirements or options.........: 
Comments: Take exposure every 4th week.

Target or lamp..........................: NONE
Type of Acquisition.....................: 
Detector for observation................: STIS/CCD
Operating mode .........................: ANNEAL
Spectral Element........................: 
Aperture................................:  
Central Wavelength......................:  
Exposure Time...........................: 0
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.:
BOP Predicted Global Count Rate for MAMA:
ETC PID IDs for Count Rates.............:
Special Requirements or options.........:
Turn of TED for 12 hours and let cool and stabilize for 3
hours when turning the TEC back on.
Comments: Take exposure every 4th week.

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# Special needs of this proposal?

Scheduling: Schedule every four weeks. Start on November  01, 2010.

Prerequisites: n/a

PDB update?               no
On-board table update?    no

# Special Requirements:
Real time?                N
Special commanding?       N
Quick Data turnaround?    N
Special timing required?  N
Other?                    N
Describe (& justify) special requirements:


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# Link to Cycle 18 Science

Fraction of science programs supported by this calibration: 60%

List categories of science which can't be executed until after this proposal:
  none
why: 

List categories of science which are best performed contemporaneous with 
this proposal: 
  none
why:

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Expected FTE weeks for analysis:                  3   
Required turnaround on analysis (weeks):          3
Data volume (Mb needed for analysis):             10.5Mb
Special software needed for analysis? (Describe):   dotnorm.cl, doanneals.cl
dotnorm.cl normalizes the darks to the ccd housing temperature.
doanneals.cl calculates the growth rates, anneal rates, number of hot pixels,
and raw mean and median dark current. saa_plot.pro tracks whether a 
sub-exposure interacted with the SAA.

Description of analysis Plans:	
Data reduction and analysis will be done using calstis and various IDL and
IRAF scripts. Data reduction will be done using calstis to reduce the raw fits
files to cosmic ray rejected fits files. Analysis will determine the location,
brightness and number of hot pixels from the pre and post-darks. From this 
analysis,  comparisons of which hot pixels persist, hot pixels that are not
affected by the annealing and annealed hot pixels are made. From these
results the growth rate of hot pixels, annealed away rate of hot pixels, mean
raw dark count rate and median dark count rates can be determined. Furthermore,
from these results, linear expressions for mean raw and median count rates per
day or year can be determined from linear fit routines. Further analysis will be
done on both types of flats to evaluate if any window contamination was acquired
during the annealing period.