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Space Telescope Imaging Spectrograph
STIS CCD Spectroscopic Flatfield Monitor C17

STIS Cycle-17 Calibration Phase-1 Template

Last Revised:                   17 March, 2009
Proposal ID:                    11852
Title:                          STIS CCD Spectroscopic Flatfield Monitor C17
PI:                             Charles Proffitt
Co-I(s):                        

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# Orbit estimates are TOTAL for all of cycle-12; assume 52 weeks) 

Total Prime Orbits:             0
External Parallel Orbits:       0
Internals or no-impact orbits:  50
Comments on orbit estimate:     6 orbits for the 1/8 week 50 CCD G430M 5216 TUNGSTEN
                                5 orbits 52X2    G430L    4300 TUNGSTEN
                                10 orbits 52X2    G430M    5216 TUNGSTEN
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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:  Obtain CCD flats on the STIS CCD in spectroscopic mode.  

Description:

1). 1 visit every 2 months for one grating (G430M, 5216 Angstroms) with
Gain= 1 & 4. Use Tungsten lamps. 6 orbits total.

2). G430M 5216 Angstroms 52X2.  4 exposures per dither position at each of 5
slitpos dither positions. For this setting, we get 2 exposures per internal orbit,
so we need 10 orbits total.

3). G430L One orbit at each of 5 slit-pos dither positions. 5 orbits total.

Follow-on to 9613

Accuracy:                       < 1%

Comments on Accuracy:           How well science data can be flattened (i.e.
                                photometry).  

Products:                       Reference files.




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# THE REST OF THIS FORM IS FOR INTERNAL USE


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Observation summary: 

# Target information (copy for each target)

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


# Exposure list plan at the Phase I level. Be as complete as reasonable. 
# If possible information should be complete enough to allow easy 
# submission of a Phase 2 from this form. However, if you have to leave
# some of the fields blank below, or want to provide the information
# in another format, that is acceptable. (Make sure you do the BOP checking
# though, as this is a phase-1 issue.)

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

The first target should be done monthly for monitoring:

Target or lamp..........................: Tungsten lamp
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430M
Aperture................................: 50CCD
Central Wavelength......................: 5216
Exposure Time...........................: 21s, crsplit=no
Number of Iterations ...................: 6  (x 21 visits)
ETC PID IDs for Count Rates.............: (Bohlin)
Special Requirements or options.........: GAIN=4, 
Comments: Every other week for 16 weeks, then once per four weeks. visits 01-21

Target or lamp..........................: Tungsten lamp
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430M
Aperture................................: 50CCD
Central Wavelength......................: 5216
Exposure Time...........................: 21s, crsplit=no
Number of Iterations ...................: 5 (x 21 visits)
ETC PID IDs for Count Rates.............: (Bohlin)
Special Requirements or options.........: GAIN=1, 
Comments: Bi-weekly for 16 weeks, then once per four weeks. visits 01-21


Target or lamp..........................: Tungsten lamp
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430M
Aperture................................: 52X2
Central Wavelength......................: 5216
Exposure Time...........................: 550s, crsplit=no
Number of Iterations ...................: 5 X 5 slitsteps
ETC PID IDs for Count Rates.............: (Bohlin)
Special Requirements or options.........: GAIN=4, dither with special slitpos pattern
Comments: Do once early in Cycle 17, repeat after 6 months with 4 iters/slit-step
visits 31-39, repeat visit 84-92

Target or lamp..........................: Tungsten lamp
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430L
Aperture................................: 50CCD
Central Wavelength......................: 4300
Exposure Time...........................: 2.5s, crsplit=no
Number of Iterations ...................: 17 x 5 visits
ETC PID IDs for Count Rates.............: (Bohlin)
Special Requirements or options.........: GAIN=4
Comments: Do three visits early, and repeat two more after 6 months

Target or lamp..........................: Tungsten lamp
Type of Acquisition.....................: n/a
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G750L
Aperture................................: 50CCD
Central Wavelength......................: 4300
Exposure Time...........................: 4.8s, crsplit=no
Number of Iterations ...................: 12
ETC PID IDs for Count Rates.............: (Bohlin)
Special Requirements or options.........: GAIN=4
Comments: do once - scattered light halo may adversely affect results.


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# Special needs of this proposal?

Scheduling: 

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

Fraction of science programs supported by this calibration:   30.2% of STIS

List categories of science which can't be executed until after this proposal:
why:

List categories of science which are best performed contemporaneous with 
this proposal: High S/N CCD spectroscopy
why: For programs that need very high S/N, it would be best if the
epoch of the flats spans the observations.  So the flat program
should be spread out over the whole cycle.

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# Analysis Plan

Expected FTE weeks for analysis:                               3
Required turnaround on analysis (weeks):                       4
Data volume (Mb needed for analysis):                         500
Special software needed for analysis? (Describe):             none

Description of analysis Plans:  (1-2 paragraphs)

Do statistical analysis of data yearly to check for any
significant changes in pixel-to-pixel flats. Coadd G430M flats
after 8 weeks and then again at end of cycle to make new pfl files. 
Coadd G430L data to make L-flat for L models. Also use
G750L data to make independent Lflat, and compare to G430L to
estimate red-halo scattered light effects.