NICMOS SMOV Update
November 4 2009
Agenda
1. Recent Activities
2. NICMOS SMOV Program Status
3. Recent Results and Analysis
- Focus Tilt measurement
- Aperture Locations
4. Tentative Forward Plan
1
Recent Activity:
• 11416 Thermal Background started Mon Oct 19
• 11417 Dark Monitoring and Detector Read Noise started Mon Oct 19
• Operation stopped Oct 22 due to SIC&DH lock-up
Planned activities:
Currently no planned activities. NICMOS/NCS warming up
Outstanding issues from previous SMOV activities:
— 11408:4 Update of nominal PAM Tilt settings visit 8
— SIAF update following analysis of 11410
2
NICMOS SMOV Status
Activity
Prop ID
Title
PI
Visits
Done
Total
Visits
Status
NIC03
11406
DC Transfer Test
Schneider
2
2
Completed
NIC04
11407
Filter Wheel Test
Wheeler
4
4
Completed
NIC05
11408
Focus/Tilt Test
Wiklind
7
8
Analysis in
progress (tilt)
NIC06
11409
FOM Functional
Dahlen
0
1
Deferred
NIC07
11410
Aperture Location
Koekemoer
3
3
Analysis in
progress
NIC08
11411
Optical Plate Scale
Wiklind
0
3
Deferred
NIC09
11412
Geometric Stability
Wiklind
0
2
Deferred
NIC10
11413
Mode-2 Coronagr. Target Acquisition
Schneider
0
(5)*
On Hold
NIC11
11414
Optimum Coronagraphic Focus
Schneider
0
(2)
On Hold
NIC12
11415
Coronagr. Performance Assessment
Schneider
0
(5)*
On Hold
NIC13
11416
Thermal Characterization
Barker
3
(100)
On Hold
NIC14
11417
Detector Read Noise and Dark Current
Dahlen
14
86
On Hold
New
11947
Dark Monitoring (C17 Cal Program)
Dahlen
48
48
Completed
*) Number of orbits changed
3
Recent Results
Glenn Schneider:
Airy Ring Asymmetry
• Average of 7 stars
• Flux normalized
• Smooth
• Measure intensity in 4
quadrants
• Asymmetry coefficient Ax,Ay
• Linear interpolation to find
minimum asymmetry
NIC2
(XTILT,YTILT) = (-2.1,+3.6)
4
Recent Results
(XTILT, YTILT) = (0.0,+1.5)
(XTILT, YTILT) = (0.0,+1.5)
(XTILT,YTILT) = (-2.1,+3.6)
(XTILT,YTILT) = (-2.1,+3.6)
(XTILT,YTILT) = (-0.5,+0.5)
(XTILT,YTILT) = (-1.5,+1.5)
5
History of optimal PAM Tilt
NIC1
XTILT
NIC2
YTILT
XTILT
YTILT
SMOV2
7
12
5
10
SMOV3b
16
14
15
10
SMOV4 (suggested values)
16
14
14
12
Reason for the discrepancy between phase retrieval and Airy
Ring Asymmetry not understood. However, the λ=1.7µm
wavefront error within the requirement (< λ/14) for either position.
Forward Plan
(depending on additional SMOV activities)
Leave NIC1 PAM unchanged
Correct NIC2 PAM with (XTILT,YTILT) = (–1.0, +2.0)
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Recent Results
Aperture Locations
• Astrometric Field (NGC188)
• Three different stars
• 9–point dither
• Detailed analysis in progress
Tentative Analysis: Compare
commanded x,y pixel with
observed
NIC1:
ΔX = –0.05” ± 0.01”
ΔY = +2.26” ± 0.01”
NIC2:
ΔX = –0.00” ± 0.07”
ΔY = +2.09” ± 0.03”
NIC3:
ΔX = +0.20” ± 0.18”
ΔY = –0.14” ± 0.15”
7
Recent Results
NIC3 :
NIC1 & NIC2:
No apparent change in aperture
+2.2” in Y, no change in X
PAM Focus change in 11408:4 +0.5mm for NIC1 & NIC2
(no focus change for NIC3)
A change in the PAM focus cause the field of view to move,
predominantly in the Y-direction:
Field of View offsets as a function of PAM Position
Camera
X–shift (arcsec/mm)
Y–shift (arcsec/mm)
NIC1
–0.018 ± 0.0005
+3.564 ± 0.0008
NIC2
–0.027 ± 0.0010
+3.568 ± 0.0010
NIC3
–0.009 ± 0.0021
+3.626 ± 0.0330
The change in nominal PAM position for NIC1 and NIC2
corresponds to a shift ΔY = +1.78”
Further results from the more detailed analysis (C. Cox)
8
Tentative Forward Plan
• NCS and NICMOS safed following the SIC&DH lock-up on October 22.
• No cold start of the NCS due to the potential for damage from ice
contamination in the circulator loop
• Discussions whether to attempt to remove the ice contamination by
purging the neon in the circulator loop (one refill available)
• No refill has previously been attempted
• Ice contamination will force warm-up at every safing
• A refill may allow operation at colder detector temperature (77.15K)
Re-start of NCS and cool-down:
Abbreviated NICMOS SMOV to verify functionality based on the
experience from SMOV3b and SMOV4 under consideration
 Filter Wheel Test
 Focus/Tilt
 Dark Characterization
 Thermal Background (continued)
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