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Space Telescope Imaging Spectrograph
Phase I: STIS CCD Imaging Flat-field Monitor

STIS Cycle-18 Calibration Phase-1 Template

Last Revised: 10/08/2010			
Proposal ID:  12406		
Title:	 STIS CCD Imaging Flat-field Monitor
PI: 	 Elena Mason	
Co-I(s): Charles Proffitt 	

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# Orbit estimates are TOTAL for all of cycle-10; assume 72 weeks) 

Total Prime Orbits:             0
External Parallel Orbits:       0
Internals or no-impact orbits:  10
Comments on orbit estimate:     
_ 8 orbits  for 50CCD and F28X50LP spread across  the cycle: one orbit
every 47 days;
_  2 orbits  for  50CORON:  observing strategy  and  scheduling to  be
decided later on during the cycle


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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:  Investigate the  flat-filed  stability during  a 1.5  months
period  and   -possibly-  map  (for  cycle  19)   a  few  non-standard
step-position for 50CORON.

Description:
Once every seven weeks, obtain a series of imaging CCD flats using the
MIRROR with  the unfiltered 50CCD  aperture and the  filtered F28X50LP
aperture. These will be used to monitor the characteristics of the CCD
response,  and to  look for  the development  of new  cosmetic defects.
Additionally,  data  using  50CORON  might  be  taken  to  map  a  few
non-standard slit wheel positions for choronography.

The program is a continuation  of cycle 17 program 11853. However, the
5 bias sequences  taken within each visit for  50CCD and F28X50LP have
been removed. The  number of flats per visit  and mask/filter has been
increased to 6.

Accuracy: <= 0.5%
Comments  on  Accuracy: How  well  the  imaging  science data  can  be
flattened. 
Products: Reference files and ISR.


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# THE REST OF THIS FORM IS FOR INTERNAL USE
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Observation summary:  

Obtain, every  ~1.5 months, two  sets of 5  STIS CCD flats,  each. The
first set will be taken with the 50CCD aperture and MIRROR, the second
flat will be taken with F28x50LP  and MIRROR. In both case the lamp in
use will be the tungsten one.  These flats will be used to monitor the
flat  field stability  across the  cycle.  Later  during the  cycle we
might obtain data using non-standard slit wheel positions with 50CORON
to map and evaluate the possibility of using the choronography mask at
different position over the detector.

# Target information (copy for each target)

Target Name.............................: Tungsten
Flux (and units)........................: Internal Tungsten Lamp

Table of exposures (copy for each exposure as appropriate/desired):

Target or lamp..........................: Tungsten
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: MIRROR
Aperture................................: 50CCD
Central Wavelength......................: n/a
Exposure Time...........................: 0.3s, crsplit=no
Number of Iterations ...................: 6
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4
Comments: monitoring, every ~1.5 month

Target or lamp..........................: Tungsten
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: MIRROR
Aperture................................: F28X50LP
Central Wavelength......................: n/a
Exposure Time...........................: 0.3s, crsplit=no
Number of Iterations ...................: 5
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4
Comments: monitoring, monthly

Target or lamp..........................: Tungsten
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: MIRROR
Aperture................................: 50CORON
Central Wavelength......................: n/a
Exposure Time...........................: 0.3s, crsplit=no
Number of Iterations ...................: 5
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4, SLITSTEPS
Comments: Do late during the cycle. Use different slit wheel positions
to map the wedge positions.

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# Special needs of this proposal?

Scheduling: 
The 50CCD and F28X50LP flats  should be taken every ~1.5 month monthly
(together in  one orbit) throughout  cycle 18.  50CORON flats  will be
requested later during cycle 18.

Prerequisites: 	       	n/a
PDB update?		n/a
On-board table update?  n/a

# 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
# Use the GO + GTO Phase 1 exposure listing and derived statistics
# posted on WWW.

Fraction of  science programs supported  by this calibration:  34% (of
STIS)

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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# Analysis Plan

Expected FTE weeks for analysis:                     0.5/month
Required turnaround on analysis (weeks):             < 1/month 
Data volume (Mb needed for analysis):                500
Special software needed for analysis? (Describe):    None

Description of analysis Plans:
We will  obtain the  flats and monitor  both their variations  and the
development of any cosmetic defects.  Will wait for three months worth
of data before attempting to build a new flat.