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NGAO SDR Agenda

NGAO SDR Agenda. 9:00 Welcome & Introductions (Armandroff) 9:10 Charge (Lewis) 9:20 Review Panel closed session (Hubin) 9:45 Re-entry for non-Panel participants 9:50 Comments from Chair (Hubin) 10:00 NGAO Report 17:30 General Discussion & Questions (Hubin et al.) 18:00 End.

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NGAO SDR Agenda

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  1. NGAO SDR Agenda 9:00 Welcome & Introductions (Armandroff) 9:10 Charge (Lewis) 9:20 Review Panel closed session (Hubin) 9:45 Re-entry for non-Panel participants 9:50 Comments from Chair (Hubin) 10:00 NGAO Report 17:30 General Discussion & Questions (Hubin et al.) 18:00 End KAON 584: NGAO SDR Presentation

  2. Keck AO has been a tremendous success thus far Galactic Center Crab Nebula LGS AO Kuiper Belt objects Substellar binaries Merging galaxies

  3. AO Science Productivity • 175 refereed AO science papers • 38 LGS AO • 18 Interferometer

  4. Most recent AO upgrade, NGWFC, resulted in significant performance gains Laser Guide Star Natural Guide Star 60+% Strehl for R=14 NGS

  5. WMKO is committed to raisingneeded NGAO funds • Funding plans will be reviewed by CARA Board • Goodwin, Armandroff, Bolte & Kulkarni are charged with NGAO fundraising • 2/3 private support • Very active Advancement Office at WMKO • MOSFIRE: about 50% private support • 1/3 federal support • All relevant funding opportunities • ExoPlanet Task Force recommendation: “Implement next-generation high spatial resolution imaging techniques on ground-based telescopes (AO for direct detection of young low mass companions)”

  6. Welcome Attendees Reviewers: Norbert Hubin (Chair - ESO), Brent Ellerbroek (TMT), Bob Fugate (NMT), Andrea Ghez (UCLA), Gary Sanders (TMT), Nick Scoville (CIT) SSC: Jean Brodie (UCSC), Tom Greene (NASA), Mike Liu (UH), Chris Martin (CIT), Jerry Nelson (UCSC) TSIP: Robert Blum, Mark Trueblood Directors: Taft Armandroff (WMKO), Hilton Lewis (WMKO), Shri Kulkarni (CIT) NGAO Participants: CIT: Antonin Bouchez, Rich Dekany, Anna Moore, Viswa Velur UCSC: Don Gavel, Renate Kupke, Chris Lockwood, Claire Max, Liz McGrath, Marco Reinig WMKO: Sean Adkins, Erik Johansson, David Le Mignant, Chris Neyman, Peter Wizinowich

  7. Thank you for your role in making Keck NGAO a success!

  8. Review Panel Report Questions • Assess the impact of the science cases in terms of the competitive landscape in which the system will be deployed. • Assess the maturity of the science cases & science requirements and the completeness & consistency of the technical requirements. • Evaluate the conceptual design for technical feasibility & risk, & assess how well it meets the scientific & technical requirements. • Assess whether the design can be implemented within the proposed schedule & budget. • Evaluate the suitability & effectiveness of the project management, organization, decision making & risk mitigation approaches, with an emphasis on the next project phase (preliminary design) and also with respect to the entire project. • Provide feedback on whether the overall strategy will optimize the delivery of new science. • Gauge the readiness of the project to proceed to the preliminary design phase.

  9. NGAO SDR Agenda 9:00 Welcome & Introductions (Armandroff) 9:10 Charge (Lewis) 9:20 Review Panel closed session (Hubin) 9:45 Re-entry for non-Panel participants 9:50 Comments from Chair (Hubin) 10:00 NGAO Report 17:30 General Discussion & Questions (Hubin et al.) 18:00 End

  10. NGAO System Design Review Report Peter Wizinowich, Rich Dekany, Don Gavel, Claire Max for NGAO Team: S. Adkins, B. Bauman, A. Bouchez, M. Britton, J. Bell, J. Chin, R. Flicker, E. Johansson, R. Kupke, D. Le Mignant, C. Lockwood, E. McGrath, D. Medeiros, A. Moore, C. Neyman, M. Reinig, V. Velur System Design Review April 21, 2008

  11. NGAO SDR Agenda 10:00 Introduction & Presentation Approach (Wizinowich) 10:05 Science Cases & Science Requirements (Max) SCRD 11:15 Break 11:30 Requirements (Wizinowich) SRD,FRD 12:00 Design (Gavel) SDM 12:30 Lunch 13:30 Design Q&A (Gavel) SDM 14:00 Performance Budgets (Dekany) SDM 14:45 Project Management (Wizinowich) SEMP 15:15 Risks (Wizinowich) Risk KAONs 15:45 Break 16:00 Cost Estimate (Dekany) SEMP 16:40 PD Schedule & Budget (Wizinowich) SEMP + Phased Implementation 17:20 Conclusion (Wizinowich) 17:30 General Discussion & Questions (Hubin et al.) 18:00 End

  12. Tomorrow’s Agenda 8:30 Review Panel closed session (Hubin) 9:30 Questions for NGAO EC as needed 10:00 Review Panel closed session 11:30 Review Panel draft report (Hubin) To Directors & NGAO EC 12:15 Lunch 13:00 End

  13. Presentation Approach • The agenda topics were selected to correspond to the major System Design deliverables and the 7 topics in the Review Panel Charge. • With input from the Panel Chair. • Each session in the agenda is organized to: • Provide a brief overview to address the specific charge & associated questions. • Provide answers to major questions from the reviewers. • Provide time for additional reviewer questions & team responses. • Assumptions: • People have read the System Design materials. • Reviewers have read our responses to their questions. • 89 questions received & answered. • We will not need to use this meeting to bring people up to speed.

  14. Science Case & Science Case Requirements

  15. Charges 1 & 2: Science Cases • Charge 1: “Assess the impact of the science cases in terms of the competitive landscape in which the system will be deployed.” • “Are the science cases given in the Science Case Requirements document complete & compelling?” • Charge 2: “Assess the maturity of the science cases & science requirements ...” • “Are the science requirements clear, complete & compelling?” • NGAO Team response: • NGAO will provide the WMKO community with an extremely competitive & complementary facility. • The science cases addressed to date are complete and compelling, and the science requirements are well defined. • Some requirements will be further developed during PD.

  16. We categorized science cases into 2 classes • Key Science Drivers: • These push the limits of AO system, instrument, and telescope performance. Determine the most difficult performance requirements. • Science Drivers: • These are less technically demanding but still place important requirements on available observing modes, instruments, and PSF knowledge.

  17. “Key Science Drivers” (in inverse order of distance) • High-redshift galaxies • Black hole masses in nearby AGNs • General Relativity at the Galactic Center • Planets around low-mass stars • Asteroid companions

  18. “Science Drivers” (in inverse order of distance) • Gravitationally lensed galaxies • QSO host galaxies • Resolved stellar populations in crowded fields • Astrometry science (variety of cases) • Debris Disks and Young Stellar Objects • Giant Planets and their moons • Asteroid size, shape, composition

  19. Conclusions from Science Cases • Our scientists want a high performance AO system that will enable a wide variety of science cases • They want it to open up new vistas of both wide and narrow field science at shorter wavelengths and higher sky coverage • We determined that these science goals could best be met by using new technologies rather than modest extension of existing ones • Scaling existing technologies did not meet the desired science performance (KAON 461) • Any new Keck AO system will be expensive, and hence should have a commensurately large payoff • Keck has an excellent history of world leadership in AO • First high-order AO systems on 8-10 m telescopes • First operational laser guide star • High payoff at modest risk are consistent with Keck’s approach to science and instrumentation

  20. Charge 1: “Assess impact of science cases in terms of competitive landscape...” • Other ground-based observatories • JWST & ALMA • TMT

  21. NGAO in the world of 8-10 m telescopes: Uniqueness is high spatial resolution, shorter ’s, AO-fed NIR d-IFS • Most 8-10 m telescopes plan either high contrast or wide field AO • Only the VLT has a narrow-field mode (7.5” FOV, 10% Strehl @ 750 nm)

  22. JWST will push major advances in: • End of the Dark Ages • Assembly of galaxies • Birth of stars, protoplanetary systems • Properties of planetary systems including our own Our goal is to position NGAO to build on, and complement, JWST discoveries

  23. Competitive Landscape: JWST • JWST advantages • JWST will have better sensitivity than NGAO (low backgrounds) • Diffraction limited imaging between 2.4 and 5 m • Multiplexed slit spectroscopy (x 100) • But only 1 IFU • Maximum spectral resolution R = 2700 • Keck NGAO advantages • Better spatial resolution than JWST at wavelengths below 2 m • JWST pixels under-sample the diffraction limit at these wavelengths • Spectroscopy at spatial resolutions < 0.1” • Multi-IFU spectroscopy • Spectroscopy at spectral resolutions R > 2700 • Higher resolution imaging at wavelengths < 2 m

  24. Competitive Landscape: ALMA • Millimeter and sub-millimeter wavelengths (0.35 - 9 mm) • Typical spatial resolutions ~ 0.1” • Resolutions for widest arrays as low as 0.004” at the highest frequencies • ALMA science: regions colder and more dense than those seen in the visible and near-IR by NGAO • Keck NGAO observations of H2 and atomic hydrogen near IR emission lines: characterize warmer outer regions of the disks and molecular clouds seen by ALMA, at similar spatial resolution • Keck NGAO and ALMA observations complementary for: • Spatially resolved galaxy kinematics, z < 3 • Debris disks and young stellar objects

  25. Complementarity with TMT • TMT (2017?) • TMT has significant spatial resolution & sensitivity advantages over NGAO • NGAO d-IFS has spatially resolved spectra & higher spatial resolution than TMT’s IRMS; available a generation before IRMOS • NGAO proving MOAO, variable asterisms, Point-and-Shoot sharpening, MEMS DM’s, to TMT’s benefit

  26. NGAO with multiplexed IFU: a real complement to TMT • TMT IRMS: AO multi-slit (MOSFIRE) fed by MCAO • Slits: 0.12” and 0.16”, Field of regard: 2 arc min • Lower backgrounds: 10% of sky + telescope • NGAO with multiplexed deployable IFUs • MOAO  better spatial resolution than MCAO over full field • Better spatial resolution: 0.07” is current spec. • Higher backgrounds:  30% of sky + telescope (but much better than current AO system) • TMT IRMS strengths: lower backgrounds, higher sensitivity • NGAO d-IFU strengths: higher spatial resolution, 3D information, wide field performance • NGAO d-IFU a pathfinder for TMT IRMOS

  27. Charge 2: “Assess the maturity of the science cases & science requirements ...” • Science Cases fully described in the Science Case Requirements Document (SCRD, KAON 455) • Here: Choose one “Key Science Driver” and walk through the requirements process with you Galaxy Assembly and Star Formation History • Broad scientific goals • Major sub-cases • How requirements were derived • Remaining issues

  28. JWST will excel here High Redshift Galaxy Internal velocities Star Formation star cluster Super- nova Bulge Metallicity Spiral Arm Galaxy Assembly and Star Formation History: Focusing our Analysis • “High Redshift Galaxies” has very wide scope • z > 6: Finding and characterizing galaxies • 3 < z < 6: Morphologies, colors • 1 < z < 3: Internal kinematics, structure at time of peak star formation • To define “Key Science Driver” we focused on 1 < z < 3 • 1 < z < 3 epoch: spatial resolution of 10-m telescope has strong impact • Prominent emission lines redshifted to J, H, K bands • Sufficient signal-to-noise to spatially resolve internal kinematics, star formation rates, metallicity gradients using spatially resolved spectroscopy

  29. What is happening to galaxies at 1  z  3? • At z ~ 1 – 3, galaxies accumulate most of their stellar mass, rate of major mergers peaks. • This activity transforms irregular galaxies into the familiar Hubble sequence of the local universe. • Studying these galaxies in detail is key to understanding galaxy formation and the buildup of structure in the universe. • Global properties of these galaxies are being well studied. • Little is known about internal kinematics or small-scale structure, mode of dynamical support, spatial distribution of star formation. • Is star formation due to rapid nuclear starbursts during major mergers? To circum-nuclear starbursts caused by bar-mode or other gravitational instabilities? Or to consumption of gas reservoirs in stable rotationally-supported structures?

  30. Substantial benefit from observing many of these galaxies at once • In survey mode, could make good use of as many as 20-25 IFUs at once • In more focused mode, typical science paper will study a sub-category of these galaxies. Multiplexing factors of 6-12 fit many subcases.

  31. Many Sub-Cases, Galaxies at 1  z  3 • Kinematic evolution from random sub-pieces to organized rotation • Patterns of star formation (nuclear first? rings? uniform? ...) and their trends with redshift • Dependence of star formation rate on current merger activity and/or existence of close companion galaxies • How does status as Active Galactic Nucleus influence star formation pattern and rate? • Does status as Active Galactic Nucleus correlate with recent merger activity? Existence of close companion galaxies? • Sub-classes of targets will be selected using ongoing large surveys (e.g. COSMOS, GOODS, ...) Goal is to derive science requirements to jointly optimize as many of these sub-cases as possible

  32. Requirements Shared by Most Sub-Cases • Spatially resolved spectroscopy (2 spatial dimensions) • e.g. to distinguish ordered rotation from discrete sub pieces, to see patterns of star formation or metallicity • Size of field for each galaxy? “Typical” galaxy is 1 arc sec; want additional real estate in order to measure sky background or to accomodate larger galaxies when needed. Chose 1” x 3” as minimum field size for IFUs. • High sky coverage fraction: ≥ 30% • Multiplexing to maximize science return per hour of observing • Multiplexing factor of N is equivalent to N Keck Telescopes • Requirement: Target sample size of ≥ 200 galaxies observable with ~10 nights of allocated telescope time. (More on next slide) • Spectral bands: J, H, K with spectral resolution 3000-4000 • Major emission lines redshifted into JHK (H and [NII], [OII], [OIII]) • Spectral resolution chosen to look between the OH night-sky lines • Choose lowest resolution that does this, to preserve faint-object sensitivity

  33. Sensitivity Requirement is the Hardest to Jointly Optimize • Overall requirement: spectra of ≥ 200 high-z galaxies in 10 nights of observing time • Must be able to observe ≥ 20 galaxies per 10-hour night (see table) to SNR ≥ 10 • Choice of pixel / spaxel scale is key, for galaxies with at least some fuzzy structure • Extended H emission, low surface-brightness disks, largest galaxies, ... • For these, larger pixels/spaxels are better for SNR. Optimum at 0.1”/px or more. • But of course larger pixels/spaxels are worse for spatial resolution • For smaller galaxies at 1  z  3, or those that have point-like substructures, pixel scales  0.05” are best * Not desirable

  34. Sensitivity Requirement and Pixel/Spaxel Size, continued • Recap: • Sensitivity will depend on pixel/spaxel size • Different sub-cases of the 1 ≤ z ≤ 3 science case optimize at different pixel/spaxel sizes • Large galaxies with diffuse Ha emission: 0.1” / px or more • “Galaxies” consisting of several point-like star-forming knots: ≤ 0.05” • Compromise for the deployable IFU: pixel/spaxel scale = 0.07” • Narrow-field high-resolution IFU (OSIRIS-like) will have variable scales. For example OSIRIS goes down to 0.02” • Implications for the deployable IFU: • Can meet 200-galaxy requirement with 0.07” spaxels, background due to AO less than 30% of unattenuated (sky + telescope) between OH lines • Yields 2-3 hr integration times (see next slide), min 4-6 deployable IFUs

  35. Requirement on AO background: Example of analysis logic • Tint = 3 hours  AO contribution to background = 30%, 6 IFUs • Then 70% throughput  cool AO system to -15C • Calculations will be refined for PDR, now that optical design is defined

  36. Each Science Driver has a “Requirements Table” • Summarizes requirements discussed in text and figures • Formatted for input into System Requirements Document and into the Contour Database of Functional Requirements • Example: part of the Requirements Table for High-Redshift Galaxies

  37. Science Team Tasks During PD Phase • Expand upon goals of “Science Drivers”, and finish documenting the AO performance necessary to achieve these goals. • Generate a Science Requirements Summary Matrix that rolls-up the most demanding requirements for each part of the architecture • Develop detailed observing scenarios for each “Key Science Driver” to define pre- and post-observing tools and observing sequences. • Detailed science simulations of “Key Science Drivers” to assess the required level of PSF accuracy, stability, uniformity, and knowledge as a function of position and time. Implications for: • achievable astrometric and photometric accuracy • achievable contrast ratio • morphological studies

  38. Science Team Tasks During DD-FSD Phases • Develop a “Design Reference Mission” for at least two “Key Science Drivers” • Simulate expected on-sky performance. • End-to-end simulation: planning tools, observing proposal, observing sequences, science operations, PSF models, analysis tools, data products. • Integrate tasks and deliverables from throughout the NGAO Work Breakdown Structure to ensure they work together and provide a seamless observing process that meets all specifications. • Design Reference Mission will help ensure that commissioning runs smoothly, to advance to full-scale science operations as quickly as possible and maximize the scientific return of NGAO.

  39. Additional Science Team Efforts • Continued discussions with Keck community to ensure that science case requirements remain consistent and up-to-date with changing methodology, advancing AO system design, and maturing instrument concepts. • Input from observers to improve planning tools, observing practices, support, and efficiency. • Feedback regarding NGAO science opportunities that complement other ground-based AO and space-based facilities, and that take advantage of the uniqueness space provided by NGAO at Keck.

  40. Reviewer Q & A • MCAO/MOAO Trade-offs • Contrast requirements and capabilities • PSF requirements and analyses

  41. MCAO/MOAO Tradeoff: Key Science Drivers • Four of the five Key Science Drivers use very narrow fields: • Black hole mass in nearby AGNs ( 5 arc sec field) • General Relativity in the Galactic Center (10 arc sec field) • Extrasolar planets around nearby stars (5 arc sec field) • Minor planet multiplicity (3 arc sec field) • The fifth Key Science Driver, Galaxy Assembly and Star Formation History, needs wide fields and high sky coverage. • In all Science Cases, infrared tip-tilt stars need to be AO-corrected, for high sky coverage. • More on this later

  42. All narrow-field Key Science Drivers are within one isoplanatic angle • Nearby AGNs, extrasolar planets, multiplicity of minor planets use 0.85  1.6 m, field radii  3 arc sec • Galactic Center uses  ~ 2.2 m, field radius  5 arc sec These cases don’t need MCAO or MOAO for the science field

  43. But most narrow field science cases need MCAO or MOAO for high sky coverage • Laser tomography needs 3 natural stars for tip-tilt and other low modes • For high sky coverage, these tip-tilt stars must be AO-corrected (can use fainter stars which are more plentiful) • Drives towards infrared tip-tilt stars, since these will have better AO-correction than visible ones • For AO correction of widely spaced tip-tilt stars, must have laser asterism extending to relatively large radius • TMT NFIRAOS: 2 arc min technical field for tip-tilt sensors, lasers on 1.2 arc min diameter circle. • NGAO: 2.5 arc min technical field for tip-tilt sensors; point 3 lasers directly at tip-tilt stars; science lasers variable up to 2.5 arc min diameter field. • Can be done either using overall wide-field MCAO correction, or putting MOAO units within each tip-tilt sensor. • This decision is independent of whether science field uses MCAO or MOAO.

  44. Can be done by mosaicing smaller fields Science Drivers (not “Key”): Which ones need wide science field? • Narrow Field Science (< isoplanatic angle, don’t need MOAO or MCAO except for tip-tilt) • QSO Host Galaxies • Gravitational lensing of galaxies by galaxies • Some of the narrow-field astrometry science • Debris disks • Young Stellar Objects • Size, shape, composition of minor planets • Gas giant planet moons • Uranus and Neptune • Wider Field Science • Gravitational lensing by clusters • Some wide-field astrometry science cases • Resolved stellar populations in crowded fields • Imaging of Jupiter and Saturn disks and rings • Imaging of Uranus and Neptune rings

  45. Potentially benefits most from MCAO Science Drivers (not “Key”): Which ones need wide science field? • Narrow Field Science (< isoplanatic angle, don’t need MOAO or MCAO except for tip-tilt) • QSO Host Galaxies • Gravitational lensing of galaxies by galaxies • Some of the narrow-field astrometry science • Debris disks • Young Stellar Objects • Size, shape, composition of minor planets • Gas giant planet moons • Uranus and Neptune • Wider Field Science • Gravitational lensing by clusters • Some wide-field astrometry science cases • Resolved stellar populations in crowded fields • Imaging of Jupiter and Saturn disks and rings • Imaging of Uranus and Neptune rings

  46. Can NGAO meet its contrast goals? • Science Case: Planets around nearby low-mass stars Giant planet (2x mass of Jupiter) Brown dwarf 1/30 mass of Sun (hidden behind occulting mask) Simulations by Bruce Macintosh and Chris Neyman

  47. Can NGAO meet its Contrast Goals? Target Sample 1: Old field brown dwarfs to 20pc Requirement: H=14, H=10 at 0.2” (2MJ at 4 AU) Target Sample 2: Young (<100Myr) brown dwarfs & low-mass stars to 80pc Requirement: J=11, 1MJ: J=11, 2MJ: J=8.5 • (minimum) J=8.5 at 0.1” • (nominal) J=11 at 0.2” • (goal) J=11 at 0.1” Target Sample 3: Solar-type stars in Taurus and Ophiuchus, and young clusters at 100-150 pc. Requirement: J=10-12, 1MJ: J=13.5, 5MJ: J=9 • (difficult goal) J=13.5 at 0.07” • (goal) J=9 at 0.07”

  48. Occulting spot sizes NGAO, no coronagraph Coronagraphs Simulations of Contrast Performance • Numerical simulation inputs: • Keck pupil • 7 layer turbulence model, median to good conditions • 36x36 subaps • Measurement errors due to spot elongation & fratricide • 1 kHz frame rate • 5 LGS at 11” • Tip/Tilt error (3 NGS, J=16 at 30”) • Static telescope errors - 65 nm • No treatment of non-common-path errors yet

  49. Target Sample 1 Target Sample 2a Target Sample 2b Target Sample 2c Target Sample 3b Target Sample 3a

  50. Conclude that Science “Requirements” (but only one “Goal”) can be met for Exoplanets science case Target Sample 1: Old field brown dwarfs to 20pc  at 8  Requirement: H=14, H=10 at 0.2” (2MJ at 4 AU) Target Sample 2: Young (<100Myr) brown dwarfs and low-mass stars to 80pc Requirement: J=11, 1MJ: J=11, 2MJ: J=8.5 • (minimum) J=8.5 at 0.1”  at 8  • (nominal) J=11 at 0.2”  at 5  • (goal) J=11 at 0.1”  Target Sample 3: Solar-type stars in Taurus and Ophiuchus, and young clusters at 100-150 pc. Requirement: J=10-12, 1MJ: J=13.5, 5MJ: J=9 • (difficult goal) J=13.5 at 0.07”  • (goal) J=9 at 0.07” ?at 5 

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