NGAO System Design Phase
Update
Peter Wizinowich, Rich Dekany, Don Gavel, Claire Max, Sean Adkins
for NGAO Team
SSC Meeting
November 6, 2007
Presentation Sequence
•
•
•
•
•
•
Management
NSF Proposals
Science & System Requirements
System Engineering
System Design
Summary
2
Management Report
10/1/06
3/31/08
PDR
System
Design
Started
now
System
Design
Review
Project Reports
•
4th & 5th reports submitted to Directors on 9/19 & 11/2
http://www.oir.caltech.edu/twiki_oir/bin/view.cgi/Keck/NGAO/SystemDesignPhasePlanning
•
Emphasis during this report period has been on:
–
–
–
–
–
System architecture evaluation & selection (June – Aug.)
Functional requirements (Aug. – Dec.)
Subsystem design (Sept. – Dec.)
Proposals to TSIP & ATI
Plus: completion of two performance budgets, incorporation of
additional atmospheric characterization data, & summary reports for
the performance budgets & trade studies
4
System
Design
Milestones
#
MILESTONE
DATE
STATUS
1
SD SEMP Approved
10/9/06
Complete
2
SD phase contracts in place
10/27/06
Complete
3
Science Requirements Summary
v1.0 Release
10/27/06
Complete
4
System Requirements Document
(SRD) v1.0 Release
12/8/06
Complete
5
Performance Budgets Summary
v1.0 Release
6/15/07
Complete
6
SRD v2.0 Release
5/22/07
Nearly complete
7
Trade Studies Complete
6/22/07
Complete
8
SRD
v3.0 Release
9/7/07
Not started
9
System Design Manual (SDM)
v1.0 Release
9/21/07
Complete
10
Technical Risk Analysis
V1.0 Release
9/21/07
Complete
11
Cost Review Complete
12/7/07
Some work as part of
system architecture
12
SDM
v2.0 Release
2/12/08
13
System Design Review
Package Distributed
3/4/08
14
System Design Review
3/31/08
15
SDR Report & Project Planning
Presentation at SSC meeting
4/14/08
Requirements 
Performance Budgets +
Trade Studies 
System Architecture +
Functional Requirements 
Subsystem Design +
Functional Requirements 
Management Plan
(post-SDR)
4 milestones completed
since June SSC meeting
5
Schedule & Budget
Schedule: 53% of System Design Phase work complete through Oct.
Budget: 64% of System Design Phase budget ($730k) spent through Sept.
–
92% of the $798k FY07 budget, excluding $20k contingency
Plan to be reviewed to ensure deliverables complete for SDR
6
NGAO Keck AO Notes
20 reports document technical progress since last SSC meeting:
KAON
484
485
487
490
491
492
493
494
495
496
497
499
500
501
502
503
504
506
509
510
511
512
Title
Optical Design Standards for NGAO
Adaptive Secondary Mirror Trade Study
LOWFS Architecture Trade Study
Rayleigh Rejection Trade Study
Performance Budget Summary
Null-mode & Quadratic Mode Tomography Error
Science Instrument Reuse Trade Study
NGAO System Design Phase Report #3
Summary of NGAO Trade Studies
MK turbulence statistics from the T6 MASS/DIMM
(restricted)
High-contrast & companion sensitivity performance
budget
NGAO System Architecture definition
Keck AO upgrade feasibility
NGAO background & transmission budgets
Keck AO Upgrade engineering costs basis
Mauna Kea Ridge turbulence models
Performance vs technical field of view for LOWFS
Split relay evaluation (packaging constraints, tip/tilt
stability)
Uplink compensation trade study
Preliminary technical risk evaluation
System Design Manual
NGAO System Design Phase Report #4
Program RequireModel
Perfor- AO Trade Laser
Mgmt
ments Validation mance Study (TS)
TS
OperInstruSystem
ations TS ment TS Architecture
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
x
All KAONs at http://www.oir.caltech.edu/twiki_oir/bin/view.cgi/Keck/NGAO/NewKAONs
7
NSF Proposals
NSF Proposals Submitted
•
NGAO preliminary design
–
–
–
•
Deployable near-IR integral field spectrograph system design
–
–
–
•
$2M TSIP proposal submitted on Aug. 31
Funds ~70% of preliminary design
Detailed schedule/budget to be determined during system design
$1.1M ATI proposal submitted on Nov. 1
Proposed to ATI program because
• Most complex NGAO instrument, with longest lead time
• Advanced nature of key components made it suitable for ATI
System design scheduled from May/08 to Dec/09
Proposal writing in both cases led by Adkins with support from WMKO
management, NGAO EC & science community
9
Deployable IFS: Project Organization
• Adkins (co-PI) : overall architecture, systems engineering, project
management
• Larkin (co-PI): IFS design, instrument scientist
• Science team members: Barton (UCI), Lu (UCLA), Shapley
(Princeton/UCLA), Steidel (CIT), Treu (UCSB)
• Optical design
– UCSC, UCLA
• MOAO
– UCSC, WMKO
• Mechanical design
– Caltech, UCLA, WMKO
• Electronics and Software
– UCLA, WMKO
Project requires close liaison with NGAO PD phase!
10
Deployable IFS: Science Cases
• Extragalactic Science
–
–
–
–
–
Galaxy Assembly and Star Formation History
Properties of Extremely High Redshift Galaxies
Cluster Scale Lensing
Stellar Populations and Kinematics in High Redshift Galaxies
Galaxy Formation and AGNs
• Galactic Science
– Young Massive Star Clusters
– Physics of Star Forming Regions
• Science cases in bold face discussed in proposal
11
Deployable IFS: Observing Features
• Entire near-IR band (J, H or K) in one exposure
• Rectangular IFS FOV 1" x 3" (baseline)
• Nominal 50 to 70 mas spatial scale, selected to match AO
performance and give 50% EE in each spatial sample
• R ~4,000
• Background limited (sky+telescope) performance goal (cooled AO
enclosure)
• Close packed mode:
Image credit: UCLA Galactic Center Group
12
Deployable IFS: Instrument Concept
14
Deployable IFS: Synergy with Other Projects
Significant commonality with key elements of TMT instruments:
• IRIS
– Image sampling
– Near-IR tip-tilt wavefront sensing
– Spectrograph
• IRMOS
– NGAO deployable IFS is a pathfinder or “prototype” instrument
– Object selection
– MOAO
• ATI Letter of support provided by TMT for “leveraging” common
areas of technical problem solving and design
15
Science Case & System Requirements
Keck leadership in AO science
• Keck LGS science dominated last week’s Ringberg
meeting on “Astronomy with LGS AO”
– 12 meaty Keck science papers
– Campbell’s stunning summary talk on Keck LGS experience
– Hans-Walter Rix: Congratulations!
• Ambitious ESO VLT future AO plans
– “Laser guide star facility” - one whole VLT telescope with two
Ground Layer AO systems (MUSE, HAWK-I)
– Relatively modest narrow-field AO system in near IR
• NGAO has unique science role
• Will maintain Keck’s world leadership!
17
Science Cases
•
Recall presentations at Keck Strategic Planning Meeting
–
–
–
–
•
Science case overview (Max)
Astrometry (Cameron & Lu)
High redshift galaxies (Steidel & Law)
Gravitationally lensed galaxies (Marshall & Treu)
One result of KSPM talk  New volunteers to work on NGAO
science cases
– Eisner, Fitzgerald, Metchev, Perrin
– Many others reiterated their interest
•
Reminder of astronomers who have been involved in science cases
& requirements subsequent to proposal:
– Ammons, Barth, Cameron, Ghez, Koo, Law, Le Mignant, Liu, Lu,
Macintosh, Marchis, Marshall, Max, McGrath, Steidel, Treu
18
NGAO is complementary to
TMT IRMS
• TMT IRMS: AO multi-slit, based on MOSFIRE
– Slits: 0.12” and 0.16”, Field of regard: 2 arc min
– Lower backgrounds: 10% of sky + telescope
• NGAO with multiplexed deployable IFU’s
– Multi-object AO  better spatial resolution (0.07”) over full
field
– Backgrounds:  30% of sky + telescope
•
•
Pros for TMT: lower backgrounds, higher sensitivity
Pros for NGAO: higher spatial resolution, 2D information,
better wide field performance, sooner than TMT
19
Progress on defining science requirements
• Release 2 of the Science Case Requirements & System
Requirements Documents are well under way
– Observatory requirements further developed
– Remaining tasks identified and assigned
– David Le Mignant & Liz McGrath supporting this effort
22
Science Requirements Summary
Requirement
l (µm)
Field of view diameter (")
Field of regard diameter (")
Pixel size (mas)
Minimum # of IFUs
IFU separation
AO Background
Sky coverage
High order WFE (nm) for ≤ 5" fov
Tip/tilt error (mas)
50% Ensquared energy (mas)
Companion sensitivity
Photometry (mag)
Astrometry (mas)
Polarimetry (%)
PSF estimation
Differential tracking
Acquisition accuracy (mas or %
of instrument field)
Dither dist (" or % of inst field)
Dither accuracy (mas)
Dither time (sec)
Micro dither distance (mas)
Micro dither accuracy (mas)
Micro dither time (sec)
Nod reacquisition time (sec)
Positioning knowledge (mas)
Science image drift (mas/hr)
NGS mode
AO instrument switching
AO backup switching
Science Cases
Visible
Imager
Spectrograph
0.7-1.0
0.7-1.0
≥3
≥ 2 (goal ≥ 3)
na
na
≤ 7 (Nyquist at R)
na
na
na
na
na
na
na
≥ 30% for X3
≥ 30% for X3
≤ 170
≤ 170
≤ 15
≤ 15
na
≤ 25
Near-IR
Imager
Spectrograph
1.0-2.4 (+Y&z)
1.0-2.4 (+Y&z)
≥ 15 for X4b
≥4
na
na
≤ 13 (Nyquist at J)
na
na
na
na
na
≤ 30% of total
≤ 30% of total
≥ 30% for X1,X3,X4b
≥ 30% for X3,X4a
≤ 170
≤ 170
≤ 15 for sky cover; ≤ 3 for G2
≤ 15
na
≤ 25
DH ≥ 5.5 at 0.5" for S1b; DJ
≥ 8.5 at 0.1" & DJ ≥ 11 at
DI ≥ 7.5 at 0.75" for S1b
na
0.2" for G1
na
g: ≤ 0.05 relative for
na
≤ 0.05 relative for S1&G1
na
≤ 1.5-2 for S1b&G1; ≤ 0.1
≤ 1.5 relative for S1b
na
for G2a
na
na
na
required
goal
required
goal
required
required
required
required
≤ 10% for IFU; ≤
≤ 10% for IFU; ≤
≤ 10%
0.25l/D for slit
≤ 10%
0.25l/D for slit
≤ 3"? or 65%
≤ 3"? or 65% of field
≤ 5"? or 33%
≤ 3"?, or 65%
≤ l/D
≤ l/D
≤ l/D
≤ l/D
≤3
≤3
≤3
≤3
≤ 0.5l/D
≤ 0.5l/D
≤ 0.5l/D
≤ 0.5l/D
≤ 0.25l/D
≤ 0.25l/D
≤ 0.25l/D
≤ 0.25l/D
≤3
≤3
≤3
≤3
≤ 10?
≤ 10?
≤ 10?
≤ 10?
≤ 0.1l/D
≤ 0.1l/D
≤ 0.1l/D
≤ 0.1 l/D
≤5
≤5
≤5
≤5
required
required
required
required
to vis spectro
to vis imager
to NIR spectro (goal: vis) to NIR imager (goal: vis)
goal: to NIR instrument goal: to NIR instrument
not required
not required
S1b,S2,S3,X3
X3
S1,S3,S4,G1,G2a,X1,X3,X4b S4,G1,G2b,X3,X4a
Near-IR
Deployable IFU
1.0-2.4 (+Y&z)
≥1x3
≥ 120
≤ 35 (2 pixels/spaxel)
4
> 1 IFU in 10x10"??
≤ 30% of total
≥ 30% for X2
derived
derived
≤ 70
na
na
na
na
PSF spectrum reqd
goal: 1 tip/tilt sensor
≤ 10% (≤ 35 relative)
≤ 2" or 65%
≤ 70
≤ 10
≤ 35
<10
≤3
≤ 30?
≤5
≤5
single IFU
not required
23
single IFU
G2b,X2
System Engineering:
System Architecture
System Architecture
Selected
•
Five architectures evaluated
versus technical, cost &
programmatic ranking criteria
–
–
–
–
–
Split relay
Adaptive secondary
Large relay
Keck I upgrade
Cascaded relay
25
Selected System Architecture
•
•
•
•
Tomography to measure
wavefronts & overcome
cone effect
AO-corrected, IR tip-tilt
stars for broad sky
coverage
Closed-loop AO for 1st relay
Open-loop AO for
deployable IFUs & 2nd relay
26
Model used to ensure Low Background
Wide-field mode
Narrow-field mode
Filte
Total
Background
Total
Background
r
transmission
transmission
(mag. arcsec-2)
(mag. arcsec-2)
J
55.6 %
15.89
37.5 %
15.88
H
62.4 %
13.71
44.9 %
13.70
K
62.0 %
13.64
45.5 %
13.18
L'
59.6 %
3.57
46.4 %
3.14
Ms
59.6 %
0.42
46.4 %
0.02
Predicted broadband transmission (telescope + AO) and background for
the Cascaded Relay candidate architecture cooled to 259.0 K.
Transmission/background model
• Detailed coating model, ~10
coating types in each
science camera & WFS path
• Selectable spectral resolution
• KAON 501
Used to ensure
efficacy of faint IFU
K-band science case
Total
AO
Telescope
Atmosphere
Wide Field Background (260 K)
28
•
Risks identified & ranked.
– One more iteration to be performed
– Will be tracked
Conse- Like# Trend quence lihood
1
2
4
4
Description
4
Inadequate PSF
calibration to
support precision
astrometry,
photometry and
companion
sensitivity
science.
3
Astrometry
performance
requirement not
achieved
5
Likelihood
Technical Risk Analysis (v1)
Completed
1
4
3
17
6-9
4
2,3
18 10-16 5
2
1
1
20
19
2
3
4
Consequences
Status
Mitigation
1) As a result of these
recommendations NGAO team
members wrote a two-year PSF
reconstruction proposal to the
CfAO that has been funded and
which will begin in Nov/07. 2)
NGAO resources will also be
applied to this problem during the
preliminary design phase. We
will consider implementation of an
atmospheric profiler and
The importance of PSF calibration experiments with the existing
and approaches to this calibration Keck AO system in support of
are documented in KAONs 474, PSF reconstruction tests and
480 and 497.
demonstrations.
1) We will continue to work with
the UCLA Galactic Center team
and CIT proper motions team to
understand the limitations
Error budget not adequately
imposed by the existing Keck AO
understood. Current
system and science instrument.
understanding and
2) An error budget needs to be
recommendations summarized in developed during the preliminary 29
KAON 480.
design phase.
5
Functional Requirements Management Database
Requirements document
section: easier to organize
final document from database
Organized by
SEMP WBS
Rational and traceability
(just text field for now)
Short name
for easier
searching
30
NGAO System Design
Design Teams
•
•
•
•
•
•
AO architecture overall + opto-mechanical (Lead - Gavel)
AO wavefront sensors (Velur)
AO operational tools (Neyman)
Laser facility (Chin)
Controls (Johansson)
Science operations (Le Mignant)
•
Process: Work scope planning sheets (21) produced for all
major design tasks
– Define tasks, approach, inputs, products & personnel
– Ensure agreement on scope
– Some still pending EC approval
32
AO Opto-Mechanical
Design
•
Field of view expanded from 120”
to 180” diameter in response to
sky coverage analysis
– Impacts on K-mirror, 2nd layer
height, deployable IFU location
•
•
•
ADC concept & location
determined
Space frame structure being
evaluated for optics support
Draft opto-mechanical ICD
produced
180” side
view
33
Laser Facility Design
•
System Architecture Draft Document generated.
– Describes pros and cons of the laser architectures.
– Describes current laser systems & their applicability to NGAO & the Keck
telescopes.
– Provides criteria for down selection process.
•
From system architecture, generated initial list of requirements and
considerations to discuss with laser vendors.
– Some of this discussion took place at CfAO laser workshop (Nov. 2)
•
•
1st order subsystem block diagram completed with interfaces shown.
Further updates to Functional Requirements Document 2.0.
36
Non-Real-Time Controls Update
•
Draft of initial system context block diagram produced
– Still needs some work to incorporate and interconnect science operations
& instruments
– Identifies the major controls modules required to implement the NGAO
system
– Will be used to guide remainder of non-RTC controls design effort
•
Next steps:
– Block level design of
individual control modules
– Revise the functional
requirements
37
Real-Time Controller Block Diagrams
Data Hardware Interfaces
Software Flow
38
Science Operations
Design
•
Draft pre-observing interfaces
specification & design manual
produced
•
System Requirements
Document updated to include
science operations
requirements from observer &
Observatory points of view
•
Working on an observation
timeline document to define
many aspects of the operations
39
Summary
•
Management
– Major milestones met
•
Exception: science/system requirements document releases v2 & 3
– Schedule slip over last 2-3 months
•
EC will be reviewing schedule & deliverables to ensure SDR is held on
schedule & within budget
•
NSF funding proposals for NGAO preliminary design & deployable
IFS system design submitted
•
Technical:
– Completed phases: performance budgets v1, trade studies & system
architecture
– System architecture selected
– Good progress on functional requirements & database implementation to
maintain them
– Subsystem design phase has begun
Team remains committed & excited about NGAO!
40