MCAO for Gemini South Preliminary Design Review

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MCAO for Gemini SouthPreliminary Design Review

• May 24-25
• Hilo, Hawaii

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MCAO Project Overview

• Brent Ellerbroek

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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

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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

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Gemini AO System Summary
System Telescope Order/Type Availability
Hokupaa North 36/NGS Curvature Now
Hokupaa-85 North 85/NGS Curvature ?
Altair North 12 by 12/NGS Shack Hartmann 2nd Sem 2002
Altair LGS upgrade North 12 by 12/LGS Shack Hartmann 1st Sem. 2004
GSAOConventional LGS AO Mode South 16 by 16/LGS Shack Hartmann 1st Sem. 2005
GSAOMCAO Mode South 16 by 16/LGS Shack Hartmann 1st Sem. 2006 (TBR)
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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

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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 DMs
• 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 DMs and
  laser beacons

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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 (CDRlate 2002)
• Successful laser development process (2002/03)

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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

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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

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MCAOPreliminary Design ProjectTeam
Associate Director For Engineering Jim Oschmann
Project Manager Brent Ellerbroek
Project Scientist Francois Rigaut
Chip Kobulnicki (U. Wisconsin) Ivan Baldry
(AAO) Eric Steinbring (UCSC) Workshop leaders and
chairs
Contracts Andy Flach
System Engineering /Modeling Brent Ellerbroek
Laser System Celine dOrgeville
Software/Controls Corinne Boyer
Coherent Technologies U Chicago/LiteCycles Starfir
e Optical Range
Les Saddlemyer (HIA) the Optical Sciences
Company SHAKTIWARE
Glen Herriot (HIA) Jean-Pierre Veran (HIA)
AO Module Eric James
Beam Transfer Optics /Launch Telescope Celine
dOrgeville
Safety System Jacques Sebag
Optics Richard Buchroeder (ODS) Jim
Stillburn (HIA)
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)
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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

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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 mm, mode-locked CW, NdYAG 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

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Technical RisksCoDR and Now
Subsystem/Component Issue(s) Progress
Laser Performance, reliability Risk reduction demonstrations
AOM optical design Packaging,performance Improved design
1 vs, 5 LGS WFS Cameras Packaging Feasible layout defined
LGS/NGS Beamsplitter Feasibility ROM quote
RTC Computational load Algorithm specifics Benchmarks Algorithm specified
LLT/BTO optical design Incomplete concept Deployable LLT Approach revised Error budgets defined Fixed LLT periscope
AOM HVA electronics Packaging Heat dissipation Space available Heat load acceptable
Reliability/availability Not evaluated Evaluated
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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

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Logistics/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)

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PDR Agenda

• Thursday, 5/24
• 0800 Welcome
• 0805 Project overview
• 0830 Science case
• 0930 Break
• 0945 System overview
• 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
• Closed committee session
• 1800 Adjourn

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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

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PDR Agenda

• Thursday, 5/24
• 0800 Welcome
• 0805 Project overview
• 0830 Science case
• 0930 Break
• 0945 System overview
• 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
• Closed committee session
• 1800 Adjourn