March 22: Initial Identification of Anomaly on HRC
Configuration:
- Mounting: ACS in TBF/Diamond Configuration, in Chamber 225
- Cooling: ASCS Simulator with GN2
- Optical Source: HRC: RAS/Cal point source
- Starting Temp: Warm, Instrument had been On for Several Hours
Results:
- Optical motion is correlated with cool-down of ASCS simulator at 1730
- Change of 7C at ASCS caused ~ 1 pixel motion
- Note that ACS Interface Plate and CCD Housing cools with ASCS
- Note that Optical Bench temperature is rising slightly through test
- No apparent motion is seen during ASCS warm-up
- Implies anomaly is not a simple CTE expansion/contraction effect
- Direction of HRC motion is:
- Parallel to floor, as viewed looking into aperture
- Side to side at the CCD, as viewed looking down on instrument
calibration 
