Transcript .ppt

2009 LO WFS Summit
A Joint Meeting of the NGAO, IRIS, and
K1 LO WFS Teams
12/15/2009
7/13/2016
Richard Dekany
1
Agenda
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8.30am-8.45am
8.45am-9.45am
9.45am-10.45am
10.45am - 11.00am
11.15am-12.15pm
12.15pm-12.45pm
12.45pm-1pm
WFS requirement comparisons RGD (15 mins)
NGAO WFS (Kent/Alex) + discussion
TMT IRIS OIWFS + discussion (David L.)
Break
Keck IR TT + discussion (Roger)
Detector update + discussion (Roger)
Summing up
LO WFS Requirements Comparison
2009 LO WFS Summit
12/15/2009
7/13/2016
Richard Dekany
3
AO system comparisons (All # TBC during meeting)
Keck 1
LGS asterism
Single, on-axis
Laser power
30 W of LMCT format
First Light Science Instrument(s)
TT NGS sharpening strategy
First light (if funded)
NGAO
Fixed 3+1 tetrad on 10” radius
and
Patrolling 3 within 60” radius
4 x 12.5 W SOR format
and
3 x 8.6 W SOR format
NFIRAOS
Fixed 5+1 on 30” radius
6 x 25 W SOR format
OSIRIS, NIR IFS and imager
NGAO NIR IFS and imager
IRIS, NIR IFS and imager
IRMS, NIR MOS
SCAO
MOAO
MCAO
2013-14 for IR TT
>= 2015
>= 2018
LO WFS Input Plate Scales
• Keck
1 arcsec = 0.727 mm
1 mas = 0.727 m
1 mm = 1.38 arcsec
1 m = 1.38 mas
• TMT
1 arcsec = 2.18 mm
1 mas = 2.18 m
1 mm = 4.29 arcsec
1 m = 4.29 mas
Driving Requirements
Keck 1
NGAO
IRIS
Tight; complex
Tight; complex
…containable w/in… 2m diameter and 750 mm
height
[REQ-3-IRISOIWFS-0010] (BFD is actually 780 mm)
~12 mas
~12 mas
…pixel IFoV shall be 4.297+-0.200 mas
[REQ-3-IRISOIWFS-0220]
Redefinable multiple RoI;
Full-field ACQ mode
Redefinable single RoI;
Full-field ACQ mode
Rapidly redefinable single RoI;
Full-field ACQ mode
ADC
No requirement
No requirement
Each WFS subass’ly shall include a separate ADC
[REQ-3-IRISOIWFS-0170]
Power dissipation
No requirement
No requirement
…< 2 W into NFIRAOS chamber… (0.5 W goal)
[REQ-3-IRISOIWFS-0090]
None
Ø120” = 87 mm
[FR-159]
…enough to meet NFIRAOS sky coverage…
[REQ-3-IRISOIWFS-0280]
TBD
[FR-177]
(typ. 2 m precision?)
ø15 mm = 20”
ø29 mm = 40” (goal)
[FR-41]
…absolute accuracy…< 2 mas RMS anywhere
in…patrol range…[e.g. < 4.6 m]
[REQ-3-IRISOIWFS-0610]
Volume constraint
Pixel IFoV
Detector readout
(per chip)
Patrol range per OSM
channel
OSM motion
accuracy/precision
Science FoV
(to not obscure)
None
No requirement
(restricted J-H FoR)
Ø58 mm = 25”
[REQ-3-IRISOIWFS-0240] (changing as of 12/15/09)
OIWFS comparisons
Keck 1
NGAO
IRIS
1 TT (TTF goal)
2 TT + 1 TTFA (dedicated)
3 TT / TTFA (selectable)
Object Selection
Mechanism
None
Theta-phi probe arms
R-theta probe arms
Active mirrors
None
32 x 32 MEMS DM
None
(accessible pupil)
LO WFS gravity
environment
Fixed at Nasmyth
OSM patrols vertical plane at
Nasmyth
Patrols horizontal plane at Nasmyth;
rotates
LO WFS acquisition
Full FoR imaging
Ø 5 arcsec OSM FoV
w/ aux. visible ACQ camera
available
Ø 4.4 arcsec OSM FoV
w/ aux. IR ACQ camera available
K (full FoR)
or
J through H (> 35” off-axis)
J through H
J through H
Number / Type of NGS
WFS
Spectral band
LO WFS Summit Wrap-Up
2009 LO WFS Summit
12/15/2009
7/13/2016
Richard Dekany
8
Areas of potential common interest
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Detectors
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HxRG characterization
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NGAO needs to tackle this in next couple months
Time studies for acquisition timeline (Bouchez)
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Collimator squiggle stage vs. sensor plunger stage
Dithering strategies?
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J through H vs. J + H (w/ possible K-blocking)
ADC designs?
Dewar thermal designs / cooling systems (Smith / Vasisht)
Small OSM focus motions?
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Linux controller implementation
Pixel sampling (/2D; arguments for J vs. H?)
Filters / Coatings
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Other interests: HgCdTe e-APD (256 x 320, ~60-80% QE coming)?
Requirement of 120 seconds each (after slew)
Component cost estimates?
Calibration units
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Positional accuracy of probe arms (e.g. I&T position calibration using aux. equipment)
AO relay distortions (e.g. using a fiducial pinhold grid mask for IRIS)