2011 March 17 1 JWST FGS & TFI CVAC Risk Mitigation Tests Pierre Chayer, André Martel, Alex Fullerton, Ed Nelan, Kevin Volk, Anand Sivaramakrishnan, Sherie Holfeltz, Comdev Canada, CSA, UdeM, HIA

Fine Guidance Sensor (FGS) Optical Layout 2011 March m 100 mm Pick-Off Mirror TMA Mirrors Focus Mirror Detectors Role of FGS: Provides centroids to the Attitude Control System.

FGS Optical Assembly 2011 March 17 3

Tunable Filter Instrument (TFI) Optical Layout 2011 March 17 4 Narrow Band Imager

TFI Optical Assembly 2011 March 17 5 Dual Wheel Collimator TMA Camera TMA Etalon Detector Assembly Kinematic Mounts

FGS & TFI Test Setup 2011 March 17 6

Chamber Darkness 2011 March 17 7

CVAC Risk Mitigation Test Objectives Verify modifications made to FSW for control of FGS. Verify modifications made to FSW for image processing. Continue with Risk Mitigation Activities for CVAC Performance Test. –Collect data that can be used to mitigate risk for the CVAC Performance Test in June. –Performance test for TFI without the Etalon. Complete Science Team Characterization activities 2011 March 17 8

CVAC Risk Mitigation Test 24 Day Test from January 10 th to February 3 rd. Test Started – January 10 th 2011 Cool-down Started – January 10 th 2011 Stable at 37 K – January 16 th 2011 FGS Powered Down – January 22 nd 2011 FGS Powered Up – January 25 th 2011 Completion of Test Plateau – January 26 th 2011 Warm-up Complete – January 29 th 2011 Test Completed – February 3 rd March 17 9

G1 Best Focus 2011 March 17 10

FGS Cal Lamp 2011 March 17 11

G2 & G1 images with Cal Lamp 2011 March 17 12

Feature Observed in G1 Cal Images 2011 March Perhaps light exits the instrument, hits a reflective surface such as OGSE rack (only for G1) and re-enters to image the Cal source…? output? Suggestion that the shape is reminisicent of the Cal source output? But how would that be imaged? Why only G1?

Feature Observed in G1 Cal Images 2011 March It is theorized that light from the cal source may exit the instrument, reflect from an external surface (OGSE?) and re- enter, reflect from the cal source output, and be imaged on the detector. Looking at the cal source testing, one can see a jet at the edge where the hemispheres join. Is there an optical path for the lines to also show up in the image? Jet

TFI Calibration Lamps 2011 March 17 15

TFI Cal Line 2011 March 17 16

Summary All objectives were completed with varying degrees of success. The team feels more confident to carry out the Proto- Flight CVAC Performance Test in June. The STScI team is looking forward to supporting the next round of tests March 17 17