1. MCAO MCAO for Gemini South Preliminary Design Review May 24-25 Hilo, Hawaii

2. MCAO MCAO Project Overview Brent Ellerbroek

3. MCAO May 24-25, 2001MCAO Preliminary Design Review3 Presentation Outline Gemini AO program overview MCAO context –Concept and benefits –Other MCAO projects –MCAO and Conventional LGS AO for Gemini-South –MCAO and Altair Project schedule, organization, and partners Progress during the Preliminary Design phase PDR groundrules, logistics, and schedule

4. MCAO May 24-25, 2001MCAO Preliminary Design Review4 Gemini AO Requirements and MCAO Science Requirements Document, 1992: –Tip/tilt correction: Image quality in K band better than 0.1 arc sec over a 1 arc min field. –Higher-order correction: Delivered on-axis H band Strehl of 50% under median seeing conditions Altair Science Requirements, 1995: –LGS AO: Objective is to increase sky coverage at above performance levels MCAO on Gemini South can provide –Mean H band Strehl of 40% over square 1 arc minute field –Sky coverage equal or superior to conventional LGS AO 18% sky coverage at galactic pole, 77% at 30 degree latitude

5. MCAO May 24-25, 2001MCAO Preliminary Design Review5 Gemini AO System Summary SystemTelescopeOrder/TypeAvailability Hokupa’aNorth36/NGS CurvatureNow Hokupa’a-85North85/NGS Curvature? AltairNorth12 by 12/NGS Shack Hartmann 2 nd Sem 2002 Altair LGS upgradeNorth12 by 12/LGS Shack Hartmann 1 st Sem. 2004 GSAO—Conventional LGS AO Mode South16 by 16/LGS Shack Hartmann 1 st Sem. 2005 GSAO—MCAO ModeSouth16 by 16/LGS Shack Hartmann 1 st Sem. 2006 (TBR)

6. MCAO May 24-25, 2001MCAO Preliminary Design Review6 MCAO Concept, Benefits, Requirements Wide field-of-view turbulence compensation –Multiple deformable mirrors conjugate to distinct ranges –Multiple wave front sensing guidestars and tomography Highly uniform point spread functions –Improved observing efficiency, simplified data reduction Satisfactory sky coverage using laser guide stars –3 tip/tilt natural guide stars correct tilt and tilt anisoplanatism Feasible AO component requirements –Orders of individual mirrors and sensors equivalent to conventional AO systems –Processing requirements now straightforward –Laser requirements equivalent to conventional LGS AO on a per- beacon basis

7. MCAO May 24-25, 2001MCAO Preliminary Design Review7 MCAO Demonstration Programs Three programs announced since Gemini MCAO CoDR Demonstrators, not facility instruments All expect first results within 2-3 years ESO –Multiple NGS WFS and two low-order bimorph DM’s –“Conventional” and/or “layer-oriented” MCAO University of Arizona –5 Rayleigh guide stars, two deformable mirrors Palomar/CfAO –Tomographic NGS wave front sensing with multiple Shack- Hartmann WFS –Potential future upgrades to multiple DM’s and laser beacons

8. MCAO May 24-25, 2001MCAO Preliminary Design Review8 MCAO and Conventional LGS AO for Gemini-South Gemini Board has approved LGS AO for Gemini-South MCAO is our long-term goal Conventional LGS AO is the first step –Subset of MCAO system with a single DM, WFS, LGS –Designs fully compatible No penalty (beyond two reflections) for including MCAO upgrade path in LGS AO design MCAO depends on several milestones –Board-mandated technical peer review (this PDR) –Review of science case and costs (CDR—late 2002) –Successful laser development process (2002/03)

9. MCAO May 24-25, 2001MCAO Preliminary Design Review9 MCAO and Altair Conjugation to altitude unsuitable for Cerro Pachon –~60% of turbulence power near the ground Systems will employ common LGS infrastructure –Safety systems –Beam transfer optics –Laser launch telescope –Control systems Laser systems will be specified/procured separately –Single or multiple lasers for MCAO –Pulsed vs. CW issues for MCAO –Need to procure Altair laser system now

10. MCAO May 24-25, 2001MCAO Preliminary Design Review10 MCAO Project Milestones Feasibility Study Report: November 1999 Conceptual Design Review: May 2000 Preliminary Design Review: May 2001 Subsystem RFPs (excepting lasers): July-August 2001 Laser System RFP: Mid-2002 Subsystem Critical Design Reviews: July-August 2002 System CDR: September 2002 Laser System CDR: Mid-2003 AO Module lab integration: 11/03-6/04 LGS subsystems integration (initial laser): 2/04-9/04 System integration and test (initial laser): 07/04-12/04 Follow-on laser integration and test: 2005

11. MCAO May 24-25, 2001MCAO Preliminary Design Review11 MCAO Preliminary Design Project Team Project Manager Brent Ellerbroek Associate Director For Engineering Jim Oschmann Contracts Andy Flach Safety System Jacques Sebag Beam Transfer Optics /Launch Telescope Celine d’Orgeville AO Module Eric James Laser System Celine d’Orgeville Software/Controls Corinne Boyer System Engineering /Modeling Brent Ellerbroek Project Scientist Francois Rigaut Coherent Technologies U Chicago/LiteCycles Starfire Optical Range Les Saddlemyer (HIA) the Optical Sciences Company SHAKTIWARE Jim Catone Brian Baumann (LLNL) Don Gavel (LLNL) Electronics Mark Hunten Paul Clark (Durham) Tim Hardy (HIA) Mechanics Andre Anthony (HIA) Joeleff Fitsimmons (HIA) Kei Szeto (HIA) Optics Richard Buchroeder (ODS) Jim Stillburn (HIA) Glen Herriot (HIA) Jean-Pierre Veran (HIA) Chip Kobulnicki (U. Wisconsin) Ivan Baldry (AAO) Eric Steinbring (UCSC) Workshop leaders and chairs

12. MCAO May 24-25, 2001MCAO Preliminary Design Review12 MCAO Project Partners Preliminary design support –HIA (RTC electronics/algorithms, reliability analysis, WFS CCD electronics, NGS T/T WFS design, mechanical design) –LLNL (BTO/LLT design/modeling) –U Durham (DM electronics) Laser risk reduction projects –AFRL, CTI, U Chicago/LiteCycles (CfAO support) Real-time control benchmarking/architecture –HIA, SHAKTIWARE (ESO support), tOSC CTIO sodium layer measurements –Imperial College (ESO and NOAO support) Laser safety and traffic control –Keck Observatory Algorithm and modeling collaborations –AFRL, CELT, CfAO, ESO, HIA

13. MCAO May 24-25, 2001MCAO Preliminary Design Review13 Preliminary Design Phase Highlights Subsystem design –AO Module opto-mechanical design –BTO/LLT layout, budgets, mechanical design –RTC benchmarking, architecture studies and algorithms –Control system software specifications Laser risk reduction –10 W, 1.319  m, mode-locked CW, Nd:YAG laser demo Science case –Santa Cruz MCAO science workshop Management and system engineering –Management and integration/test plans Modeling and analysis –Wave optics propagation simulation

14. MCAO May 24-25, 2001MCAO Preliminary Design Review14 Technical Risks—CoDR and Now Subsystem/ComponentIssue(s)Progress LaserPerformance, reliability Risk reduction demonstrations AOM optical designPackaging,performanceImproved design 1 vs, 5 LGS WFS CamerasPackagingFeasible layout defined LGS/NGS BeamsplitterFeasibilityROM quote RTCComputational load Algorithm specifics Benchmarks Algorithm specified LLT/BTO optical designIncomplete concept Deployable LLT Approach revised Error budgets defined Fixed LLT + periscope AOM HVA electronicsPackaging Heat dissipation Space available Heat load acceptable Reliability/availabilityNot evaluatedEvaluated

15. MCAO May 24-25, 2001MCAO Preliminary Design Review15 PDR Objectives Present results of the Preliminary Design effort –Science case –System performance estimates –System and subsystem design –Laser requirements and options –Program cost and schedule estimates Committee peer review of technical approach –Approval necessary for pursuit of MCAO Obtain more general feedback from the Committee –Design suggestions –Integration and test plan –Cost estimates, management plan, science case

16. MCAO May 24-25, 2001MCAO Preliminary Design Review16Logistics/Procedures Lunch here (both days) Please sign attendance sheet Design report available electronically –Viewgraphs and selected appendices available upon request Please document comments for the committee and/or Gemini on the forms provided Friday PM session restricted to the committee, vendors, and Gemini management chain We will keep to schedule –Hold all but most essential questions to end of presentation –Committee questions first, audience questions as time allows (and during breaks)

17. MCAO May 24-25, 2001MCAO Preliminary Design Review17 PDR Agenda Thursday, 5/24 0800 Welcome 0805 Project overview 0830 Science case 0930 Break 0945 System overview 1015 System modeling 1100 AO Module optics 1145 Lunch 1245 AO Module mechanics 1340 AO Module electronics 1400 Break 1415 Beam Transfer Optics 1510 Laser Launch Telescope 1545 Closed committee session 1800 Adjourn

18. MCAO May 24-25, 2001MCAO Preliminary Design Review18 PDR Agenda Friday, 5/25 0800 Laser System 0900 CTIO Sodium Studies 0915 Control System 0945 Break 1000 RTC Electronics 1045 Safety System 1100 Availability analysis 1130 Closed vendor Sessions 1200 Lunch 1300 Cost and schedule 1400 Committee session 1700 Committee report 1800 Adjourn

19. MCAO May 24-25, 2001MCAO Preliminary Design Review19 PDR Agenda PDR Agenda Thursday, 5/24 0800 Welcome 0805 Project overview 0830 Science case 0930 Break 0945 System overview 1015 System modeling 1100 AO Module optics 1145 Lunch 1245 AO Module mechanics 1340 AO Module electronics 1400 Break 1415 Beam Transfer Optics 1510 Laser Launch Telescope 1545 Closed committee session 1800 Adjourn