CD 14 tasks: V 1.0

UPDATED: 11/30/12 (ver 1.1)

Changed some blocker notes.  changed lens wheel notes.

UPDATED: 11/2/12 (ver 1.0)

I've added a bit more to the list:
Filled in filter slots, filled in decker slots, added imaging tests, added fast framerate tests, added generic data taking tests.

Configuration:

1. Tilted focal plane at detector.  
2. Incorporate directional/size indicator at cold stop.
3. Lens Wheel (note: order isn’t important, but having these components is required)
1. Mirror (will always have mirror and make it position 1)
2. open
3. 1.5” diameter ZnSe lens (note distance of lens edge relative to detector side of lens mounting barrel - would like it to be about half as much as KRS5 lens)
4. 1.5” diameter KRS5 lens (note distance of lens edge relative to detector side of lens mounting barrel - use numbers for IR focus from blog post in May 2012)
5. 1.5” diameter ZnSe blocker 
6. UKIRT filter
4. Slit wheel should have mirror in place (only 1 open position)
5. Decker Wheel filters (note: order isn’t important, but having these components is required)
1. BBP_8000_11000 + BaF2 Blocker - NEW
2. BBP_4700_5615 (no blocker) - New
3. BBP5030_5720 (filter list suggests blocker is not needed. No blocker is mentioned for CD13.  If blocker is present, should be CaF2)  CD13: decker wheel 3
4. BBP5500_6000 (filter list suggests blocker needed, but no blocker is mentioned for CD13.  If blocker is present, should be CaF2) CD13: decker wheel 4
6. Filter Wheel (note: order isn’t important, but having these components is required) 
1. Open CD13: Slot 3
2. 18a (add KBr blocker) CD13: slot 1
3. Soifer Filter - Move from Decker wheel CD13: decker wheel 1
4. 6.2 + MgF2 blocker - New
5. BP14100_850 CD13: slot 12
6. N04679-4 + CaF2 blocker.  Note that this could be N04769-4 (dyslexia) For throughput testing, this need LONG integrations or the blackbody heated up. CD13 slot 2
7. N10247-9 + BaF2 blocker - New
8. OCLI Q + BaF2 blocker - New
9. OCLI R + BaF2 blocker CD13: slot 9
10. BP6000_250 + CaF2 blocker - New
11. BP6600_320 + CaF2 blocker - New
12. N04582-8 + CaF2 blocker - New

Tasks:  As much as possible, use Mike's GUI and ND sampling schemes with any number of S's thrown in to make the integration time as desired.   

There are a couple zeroth order tests relating to the detector and how the data taking software behave

1. see if the array behaves at 0.5 second frametime, which we would like to make our default.  If it doesn't behave at 0.5 second frametime, adjust frametime by 0.1 second intervals to see at what frametime we get good behavior.  Defining good behavior may be hard, but perhaps "repeatable" is more important than absolute performance. We want there to be no (or <1%???) echos from pixels with strong emission.
2. Verify some basic readout patterns and timing.  Assuming framerate is 0.5 seconds, every integration (time between Destructive reads "Ds") will be integer multiple of 0.5 seconds.  For all integrations of two or more frametimes, we will use a combination of a non-destructive read and a destructive read for the integration (ND).  The exact integration time will be achieved by including spins (S's) where we clock through the array, but do not reset or convert.  
1. Verify that doing something like 20 D's takes 10 seconds (0.5second frametime).  Ideally, this would result in a single FITS file with naxis3 = 20.  
2. Verify that doing 20 ND's takes 20 seconds (0.5 second frametime).  Ideally this would result in single FITS file with naxis3 = 40.  Every second frame from FITS file (corresponds to the D's) should have twice the signal of the other frames.
3. Verify that we can do integrations of arbitrary length up to 30 seconds and that timing and fluxes seem accurate.  For 0.5 second frametime, 30 seconds would be "N, 58 S's, D"

Optical tests to be done are:

1. Focus in Med mode at 13.7 microns
1. Investigate whether image size depends on location on detector.  With tilting, we expect ~2500 micron difference in path length from one end of detector to the other (Based on my memory that we’re getting 6 degree tilt with a 25 mm detector -> 25000*cos(6 deg) = 2526).  Orientation should be such that adjusting echelle grating to move a spot from one side of the detector to the other results in different path lengths.
2. Adjust echelle mirror to bring gas cell pinhole spots in center of array to best focus.
3. Assuming it is measurable, determine how many turns of echelle mirror required to go from best focus at one edge of detector to best focus at the other edge.  Assuming the number in 1.1 for path length difference across the full array (2500 microns), and the 80 turns/inch pitch of the mirror screws (317.5 microns per turn), and a 2:1 change in movement at the focal plane compared to movement at the mirror, we would expect 2500/317.5/2 = 4 turns.
4. Return to best focus at center of array.
5. Measure line profile at center of array using slits 1-6 (not flux slit).
2. Focus in High res mode at 13.7 microns
1. Minimize spot size in high res mode at center of array by adjusting echelon mirror while keeping echelle mirror fixed.  Hope is that we go through focus.
2. See if possible to reduce spot size by moving echelon and echelle mirrors in opposite directions.  Hope is that we go through best focus.
3. Map spot size around best focus with +-2 turn grid on both mirrors.  
4. Measure line profile at center of detector at best focus through slits 1-6 (not flux slit).
5. If echelle mirror is at different position from med mode best focus, than measure med mode resolving power at current mirror position.
3. For those filters that have not been tested, map filter transmissions looking at continuum source with short slit.  Adjust integration time so that good signal where light comes through well, but does not drive response >1% non-linear. We will be looking for grating positions that show 1% leaks.
4. Map 18a filter with ZnSe blocker in beam and with KBr blocker in beam
5. Investigate alignment of fore-optics ellipsoid compared to entrance window. 
6. Test imaging photon rate through N04679-4 filter and through N10247-9.
7. Image cold stop in pupil mode.  Use both KRS5 and ZnSe lenses.  Experiment with how moving optics impacts pupil image.  Restrict aperture at slit plane to sharpen image and cut down photon flux.  Try N04679-4 and N10247-9 filters
8. Mount to TAAS 
1. In pupil mode with restricted aperture at slit plane, use small chopped hot plate (SCHP) to map EXES beam.  Determine size of cold stop compared to size of SCHP and location of EXES beam center.  If EXES beam is good relative to entrance window (Item 5 above), then try “walking” beam via shimming at flange to SCHP position matching SOFIA.
2. Investigate alignment compared to large chopped hot plate in pupil mode.   Goal is to see image of LCHP at cold stop.  
3. Switch to FCLS and imaging mode.  Try imaging spot.  See if can get a spectrum of it.  Move FCLS so it matches slit location (don’t move slit around).