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Hubble Space Telescope
Phase I: 12080

COS Cycle-17 Calibration Phase-1 Template

Last Revised:			12 February 2010
Proposal ID:			 
Title: COS G140L Optics Alignment and Focus 
PI: Parviz Ghavamian	
Co-I(s): Daniel Lennon, Charles Proffitt

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# Orbit estimates are TOTAL for all of cycle-17; assume 72 weeks) 

Total Prime Orbits:             5
External Parallel Orbits:       0
Internals or no-impact orbits:  0
Comments on orbit estimate:      


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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: The purpose of this program is to identify the optimum focus 
setting for the COS FUV channel + G140L grating setup.
                        
Description: A focus sweep will be performed using the B2Ia star AZV18 in the Small
Magellanic Cloud.  A sequence of time-tag spectra will be acquired with the G140L 
grating through the PSA aperture (CENWAVE=1105 A), at a range of focus settings.  There
will be 17 focus settings sampled, ranging from -800 to +800 in 100-step intervals.  The 
optimum focus will be determined by cross-correlating prominent absorption features in 
the spectra with a template high resolution STIS E140M spectrum, then choosing the focus 
setting yielding the narrowest cross-correlation profile from the sequence. This is 
similar to the focusing procedure used for the G140L grating during SMOV (PID 11484, 
Visit 3), except that the new focus sweep will extend to more extreme focus positions 
around 0 (+/-800 instead of +/-600).   The inclusion of additional focus positions 
is necessary because the G140L focus curve from SMOV (cross-correlation FWHM vs. focus 
position) is broad and shallow, making it difficult to measure the minimum in the curve.  
After obtaining an exposure at the most extreme positive focus position (+800), the 
focus is returned to its nominal position (0).  A final spectrum is then acquired at 
that position, for repeatability comparison with the earlier FOCUS=0 spectrum.


Accuracy:                       +/-50 focus steps
Comments on Accuracy:           focus position should be known to within this range
				after the calibration activity   
Products:                       flight software change (uplink of new focus position),
				possible ISR


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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:     13% (GO COS programs)

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:
why:


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

Take a sequence of time-tag spectra of AZV 18 at 13 different focus settings,
through the PSA aperture with G140L, CENWAVE=1105, FPPOS=3, FLASH=YES.
	
# Target information (copy for each target)

Target Name.............................:  AZV-18	
RA......................................:  00:47:12.1700		
Dec.....................................:  -73:06:32.68		
Flux (and units)........................:  1e-13 ergs/cm^2/s/A (@1300 A)	
Visibility window (if known or relevant):  near-CVZ
Comment on choice of target:  The target was chosen because it exhibits
deep, saturated absorption features in its STIS E140M spectra.  This includes
both narrow and broad saturated features.  At the G140L resolution, the cores
of these features are filled in by the COS LSF, but the profiles themselves
remain sharp and well defined.  This makes them useful for cross-correlation
tests against existing high resolution STIS spectra.  The target is also 
bright (V=12.5) and blue (B-V=+0.03), allowing good S/N (S/N ~ 65 @1300 A
in 900 s) to be achieved over much of the G140L spectral range.

# 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.)

- The target passes the BOP check, since it was observed by COS in the FUV
with the G140L grating during SMOV.

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

Target or lamp..........................: Target
Type of Acquisition.....................: ACQ
Detector for observation................: NUV
Operating mode .........................: SEARCH
Spectral Element........................: MIRRORA
Aperture................................: BOA
Central Wavelength......................: N/A
Exposure Time...........................: 30s 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 16.8
BOP Predicted Global Count Rate.........: 193
ETC PID IDs for Count Rates.............: COS.A232408
Special Requirements or options.........: 

Target or lamp..........................: Target
Type of Acquisition.....................: ACQ
Detector for observation................: NUV
Operating mode .........................: IMAGE
Spectral Element........................: MIRRORA
Aperture................................: BOA
Central Wavelength......................: N/A
Exposure Time...........................: 30s 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 16.8
BOP Predicted Global Count Rate.........: 193
ETC PID IDs for Count Rates.............: COS.A232408
Special Requirements or options.........: 

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 600s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-800

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 600s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-700

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-600

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-500

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-400


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-400


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 900s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-300


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 900s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-200


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 900s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=-100


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=0


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+100


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+200


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+300


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+400


Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+500

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+600

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 600s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+700

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 600s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=+800

Target or lamp..........................: Target
Detector for observation................: FUV
Operating mode .........................: TIME-TAG
Spectral Element........................: G140L
Aperture................................: PSA
Central Wavelength......................: 1105
Exposure Time...........................: 700s, FPPOS=3 
Number of Iterations ...................: 1
BOP Predicted Local Count Rate..........: 0.16
BOP Predicted Global Count Rate.........: 4100
ETC PID IDs for Count Rates.............: COS.A228779
Special Requirements or options.........: FOCUS=0