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Space Telescope Imaging Spectrograph
Phase I: CCD Spectroscopic Dispersion Solution

STIS Cycle-17 Calibration Phase-1

Last Revised:	September 8, 2009	
Proposal ID:	11858		
Title: CCD Spectroscopic Dispersion Solution
PI:	D. Lennon
Co-I(s):	C. Proffitt, W. Zheng, M. Wolfe

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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:  7

Comments on orbit estimate:     Annual monitoring program

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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 constrain the wavelength and spatial distortion maps             

Description: Internal wavecals will be obtained with all 6 gratings (G230LB, G230MB, G430L, G430M, G750L, G750M) 
supported for use with the CCD.  All observations will be obtained with the 52x0.1 aperture, which maps to 2 pixels 
at the CCD. 

The HITM1 lamp will be used, rather than the LINE lamp. The HITM1 lamp has a more favorable spatial illumination 
pattern, dropping by only a factor of 3 at row 900, relative to the
peak brightness at row 420. A comparison LINE lamp wavecal is however included with the G430L/4300 grating.               

Accuracy:                      0.2 pixels

Comments on Accuracy:    Wavelength accuracy goal for row 900. Wavelength coefficients are tabulated every 32 rows 
in the CCD dispersion (_dsp) reference file. Exposure times in this program have typically been chosen to yield a 
S/N ratio of at least 10 per pixel in row 900 after combining 32 rows. This constraint must be satisfied in the left, 
middle, and right thirds of the image. Existing HITM1 wavecals were used to estimate exposure times assuming no 
significant degradation post-SM4.      


Products:    Accuracy of the existing CCD dispersion (_dsp) reference file will assessed and described in the Cycle 17 
calibration close-out report. If necessary, a new reference file will be created and delivered along with a supporting 
Instrument Science Report.  

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# Link to Cycle 17 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:
why: Calibrations can be applied after the observations


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# THE REST OF THIS FORM IS FOR INTERNAL USE
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Observation summary: Internal wavecals (TARGET=NONE, LAMP=HITM1) will be obtained with all 6 gratings 
(G230LB, G230MB, G430L, G430M, G750L, G750M) supported for use with the CCD.  All observations will be 
obtained with the 52x0.1 aperture, which maps to 2 pixels at the CCD.

Below is a summary table with information about each grating (column 1) and central wavelength (column 2) 
combination that appears in this program. Column 3 lists exposure times with the HITM1 lamp (and in one case 
with the LINE lamp, marked in the comment column).  
                     
   Grat   Wave Exptime  GAIN  Comment
          (AA)  (s)
  G230LB  2375  220      4   
  G230MB  1713  368      1
  G230MB  1854  600      1
  G230MB  1995  190      1
  G230MB  2135   30      1  
  G230MB  2276   84      1
  G230MB  2416   41      1
  G230MB  2557   63      1
  G230MB  2697   14      1
  G230MB  2794   30		1   
  G230MB  2836   24      1
  G230MB  2976   10      1
  G230MB  3115   24      1
  G430L   4300   10      4  
  G430L   4300   10      4      LINE
  G430M   3165   10      1
  G430M   3423   10      1
  G430M   3680   10      1
  G430M   3843   10      1
  G430M   3936   13      1   
  G430M   4194   17      1
  G430M   4451   18      1  
  G430M   4706   21      1
  G430M   4961   24      1
  G430M   5093   10      1
  G430M   5216   10      1
  G430M   5471   26      1
  G750L   7751   6.2     4   
  G750M   5734   5.9     4
  G750M   6252   4.1     4
  G750M   6581   4.1     4     
  G750M   6768   3.9     4
  G750M   7283   3.9     4
  G750M   7795   29      4
  G750M   8311   10      4
  G750M   8561   10      4   
  G750M   8825   10      1
  G750M   9336   10      1
  G750M   9851  220      1  


# Target information (copy for each target)
TARGET=NONE
LAMP=HITM1
But note that for G430L there are two exposures, one with LAMP=HITM1 and the other with LAMP=LINE

Special Requirements or options.........: GAIN=1 or 4 (see table above)

Comments: 1/year

# 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):

Target or lamp..........................: HITM1
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G230LB
Aperture................................: 52x0.1
Central Wavelength......................: 2375
Exposure Time...........................: 220 S
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4
Comments: (e.g. if monitoring, specify frequency)

Target or lamp..........................: HITM1
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G230MB
Aperture................................: 52x0.1
Central Wavelength......................: various (see table above)
Exposure Time...........................: various (see table above)
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=1
Comments: (e.g. if monitoring, specify frequency)

Target or lamp..........................: HITM1 and LINE
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430L
Aperture................................: 52x0.1
Central Wavelength......................: 4300
Exposure Time...........................: 10 S
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4
Comments: (e.g. if monitoring, specify frequency)

Target or lamp..........................: HITM1
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G430M
Aperture................................: 52x0.1
Central Wavelength......................: various (see table above)
Exposure Time...........................: various (see table above)
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=1
Comments: (e.g. if monitoring, specify frequency)

Target or lamp..........................: HITM1
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G750L
Aperture................................: 52x0.1
Central Wavelength......................: 7751
Exposure Time...........................: 6.2 S
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a
Special Requirements or options.........: GAIN=4
Comments: (e.g. if monitoring, specify frequency)

Target or lamp..........................: HITM1
Type of Acquisition.....................: none - internal
Detector for observation................: CCD
Operating mode .........................: ACCUM
Spectral Element........................: G750M
Aperture................................: 52x0.1
Central Wavelength......................: various (see table above)
Exposure Time...........................: various (see table above)
Number of Iterations ...................: 1
BOP Predicted Local Count Rate for MAMA.: n/a
BOP Predicted Global Count Rate for MAMA: n/a
ETC PID IDs for Count Rates.............: n/a



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# Special needs of this proposal?

Scheduling: 

Prerequisites: none

PDB update?               N
On-board table update?    N
# 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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# Analysis Plan

Expected FTE weeks for analysis:   4 weeks                             
Required turnaround on analysis (weeks):   not critical                     
Data volume (Mb needed for analysis):   400 Mb                        
Special software needed for analysis? (Describe): Custom IDL software may be needed to create new dispersion (_dsp) reference files.

Description of analysis Plans:	
Raw wavecal images will be self-calibrated using Calstis software. Existing wavelength solutions will be tested with available software within IRAF.