GSAOI CONCEPTUAL DESIGN REVIEW DOCUMENTATION VOL. 2 Submitted to the International Gemini Project Office under AURA Contract No. 9414257-GEM00304 Research School of Astronomy and Astrophysics Australian National University Canberra, Australia August 20-21, 2002 AUSTRALIAN NATIONAL UNIVERSITY RESEARCH SCHOOL OF ASTRONOMY AND ASTROPHYSICS This page is left blank intentionally. CONCEPTUAL DESIGN REVIEW VOL. 2 - ii - AUSTRALIAN NATIONAL UNIVERSITY RESEARCH SCHOOL OF ASTRONOMY AND ASTROPHYSICS TECHNICAL REVIEW GSAOI Conceptual Design Review Document Research School of Astronomy and Astrophysics Australian National University Canberra, Australia August 20-21, 2002 CONCEPTUAL DESIGN REVIEW VOL. 2 - 1 - AUSTRALIAN NATIONAL UNIVERSITY RESEARCH SCHOOL OF ASTRONOMY AND ASTROPHYSICS This page is left blank intentionally. CONCEPTUAL DESIGN REVIEW VOL. 2 - 2 - AUSTRALIAN NATIONAL UNIVERSITY RESEARCH SCHOOL OF ASTRONOMY AND ASTROPHYSICS Table of Contents 1 Overview ....................................................................................................................... 11 1.1 Design Priorities......................................................................................................... 11 1.2 Technical Implementation......................................................................................... 11 1.3 Systems Design........................................................................................................... 12 1.4 Optical Design............................................................................................................ 13 1.5 Mechanical Design .................................................................................................... 15 1.6 Detector Control Systems........................................................................................... 16 1.7 Instrument Control System........................................................................................ 18 1.8 Control Software ........................................................................................................ 18 1.9 Summary.....................................................................................................................19 2 Systems Design ............................................................................................................. 20 2.1 Introduction................................................................................................................20 2.2 Subsystem Interfaces.................................................................................................. 20 2.3 Environmental Heat Load ......................................................................................... 22 2.4 Mass Budget ............................................................................................................... 22 2.5 Center of Gravity Budget ........................................................................................... 22 2.6 Instrument Volume .................................................................................................... 22 2.7 Optical Image Quality Budget ................................................................................... 23 2.8 Throughput Budget.................................................................................................... 23 2.9 Emissivity Budget....................................................................................................... 23 2.10 Mechanical Flexure Performance .......................................................................... 23 2.11 Thermal Enclosure Space Allocation...................................................................... 23 2.12 Electrical Power Budget .......................................................................................... 26 2.13 Handling Equipment ............................................................................................... 27 2.14 Calibration Requirements........................................................................................ 27 2.15 Differential Atmospheric Refraction....................................................................... 29 2.16 Risk Analysis ............................................................................................................ 30 3 Optical Design .............................................................................................................. 33 3.1 Introduction................................................................................................................33 3.2 Cryostat Window Modification.................................................................................. 33 3.3 Input Image Condition............................................................................................... 33 3.4 General Layout........................................................................................................... 34 3.5 Imager Design............................................................................................................ 34 3.6 On-Instrument Wave-Front Sensor Design.............................................................. 55 3.7 Lens Mounting System .............................................................................................. 66 3.8 Cryogenic Compensation........................................................................................... 66 3.9 Filter Selection ........................................................................................................... 68 3.10 Optical Coatings....................................................................................................... 70 3.11 Emissivity.................................................................................................................. 70 3.12 Baffling..................................................................................................................... 70 CONCEPTUAL DESIGN REVIEW VOL. 2 - 3 - AUSTRALIAN NATIONAL UNIVERSITY RESEARCH SCHOOL OF ASTRONOMY AND ASTROPHYSICS 3.13 Blackening................................................................................................................ 71 3.14 Thermal Radiation................................................................................................... 71 3.15 Lens Material Availability ....................................................................................... 71 3.16 Lens Manufacture.................................................................................................... 71 3.17 Optical Design Risks ................................................................................................ 72 4 Mechanical Design ....................................................................................................... 74 4.1 Introduction................................................................................................................74 4.2 External Components ................................................................................................ 75 4.3 Cryostat Mechanical Design...................................................................................... 75 4.4 Imager Mechanical Design ....................................................................................... 78 4.5 OIWFS Mechanical Design ...................................................................................... 91 4.6 Instrument Alignment................................................................................................ 96 4.7 Flexure Analysis ...................................................................................................... 100 4.8 Instrument Integration ............................................................................................ 104 4.9 Handling Procedures ............................................................................................... 105 4.10 Mechanical Design Risks ...................................................................................... 107 5 Detector Control Systems.......................................................................................... 109 5.1 Introduction.............................................................................................................. 109 5.2 Imager Detector System........................................................................................... 109 5.3 OIWFS Detector System .......................................................................................... 145 5.4 Detector Systems Risks............................................................................................. 147 6 Instrument Control System....................................................................................... 149 6.1 Introduction.............................................................................................................. 149 6.2 Mechanisms Control System ................................................................................... 149 6.3 Temperature Control System................................................................................... 154 6.4 Thermal Enclosures................................................................................................. 155 6.5 Manufacture............................................................................................................. 160 6.6 Instrument Control System Risks............................................................................ 162 7 Control Software.......................................................................................................