CCAT Primary Mirror Panel Study Mid –Term Status Review Xinetics Inc. 115 Jackson Road Devens, Massachusetts 01434-5022

AGENDA Profile of Xinetics & Capabilities CCAT Specifications & Residual Error Budgets CCAT Primary Mirror Pattern & Panel Configuration Trade Study Results Sample Panel Design & Performance Assesment Synopsis of Panel Manufacture Initial Risk Assessment

XINETICS – A Profile Founded In 1994 by Mark Ealey, President, To Exploit Deformable Mirror Technology Now Recognized As Principal Supplier To Government & Commercial Markets Supplier Of SiC Passive & Active Mirror Substrates Corporate Offices, Engineering & DM Manufacturing Done In 55K Ft2 Building In Devens, Massachusetts SiC Production Done In Templeton, MA, 25 Miles West Of Devens All SiC Production Activity To Be Consolidated In A 65K Ft2 Building In Devens In 2005 Principal Developer Of Replication Technology To Obviate Need For Polishing Current Employees – 72

1M Closed Back SiC Passive Mirror Blank An Example Of Xinetics Capabilities

CCAT Specifications Our Understanding Diameter 25M Center Hole Diameter 3.0M Figure F/0.6 Parabola Conic Constant -1.00154 Vertex ROC 30M Max. RMS Figure Error 5.0mm (over a 2cm dia. on 2mm grid) Reflectivity >80% @ 10m; >90% - 250 to 3mm No. Panels/No. Rings ~145 / 6 or 7 Panel-Panel Gap 2 to 5mm Support Points 3 Mandrel Roughness 25 to 30nm RMS Panel Roughness 1.25 x Mandrel Roughness Elevation Range TBD (Zenith Assumed for Study) Environments Isothermal Temperature Range 25C to 20C Altitude 16,400 – 18,400Ft Pressure 495 – 545 Kpa Relative Humidity 0 to 95% Temperature Gradients Axial 2C Lateral 2C Across Array

FIGURE ERROR SOURCES & BUDGET ALLOCATIONS REQUIREMENT IS 5.0 mM RMS ERROR VALUES IN MICRONS RMS

Preferred Panel Configuration Trapezoidal Perimeter Shape Panel – Fits In 2m x 2m Square 6 Concentric Rings, 5mm gaps 162 Panels RBO SiC Closed Back, Triangular Cell Core Substrate With Replicated Reflective Surface 3 Point Bipod Support Other Option Explored Hexagonal Panels – Requires Greater Number of Panels, Increases Costs

Panel Number & Dimensions For 6 Ring Pattern Ring No. No. Panels Arc Length - m Radial Dim. - m 1 12 1.740 1.828 2 18 1.799 1.828 3 24 1.828 1.828 4 30 1.845 1.828 5 36 1.862 1.828 6 42 1.865 1.828 Total Number of Panels - 162 25M OD, 3M ID 5 mm Gaps

Trade Studies Model Xinetics uses a Spreadsheet program to conduct trade studies. It is designed to provide data that leads to the selection of parameters (e.g., material properties, overall thickness; open or closed back; facesheet, backsheet, & rib thicknesses; triangular,square, or hex core geometry; core size; thickness and depth of cathedral ribs; active or passive control) to enable FEA modeling & refinement of the parameter set consistent with error budgets. The following is the model used in our trade studies. RBO SiC E = 4.5x107psi; r = 0.1060lbs/in3 Plano Shape 85 in. Diameter (Same Area As Concept Design) Closed Back With Triangular Core 5.918in. Cell Side Length No Cathedral Ribs Facesheet, Backsheet, Rib THK 0.120in. / 0.06 & 0.12 / 0.06 & 0.12 Passive, no Actuators

DESIGN OPTIONS CONSIDERED & TRADE SUMMARY Thickness - in 2.5 3.5 4.0 4.5 5.0 Face sheet Thickness - in 0.12 Rib Thickness - in 0.04 Back sheet Thickness - in 0.06 Weight – lbs ./ Kg 133 / 60 224 / 102 269 / 122 292 / 133 314 / 143 337 /153 Area – in2/ M2 5674 / 3.66 Areal Density – Kg / M2 16.5 27.9 33.4 36.2 39.0 41.8 Gravity SAG Edge Clamped – mm PV / RMS 3.33 / 0.95 3.59 / 1.03 2.0 / 0.58 1.6 / 0.46 1.34 / 0.38 1.13 / 0.32 Simply Supported – mm PV / RMS 15.03 / 4.29 16.18 / 4.62 9.14 / 2.61 7.32 / 2.09 6.04 / 1.73 5.09 / 0.32 3 Pt (est.) – mm RMS 2.14 2.31 1.31 1.05 0.87 0.73 Free-Free-Free – 1st Mode Hz 179 172 230 257 283 308

Sample SiC Panel Design Option3 Selected Taken From Third Ring From Third Ring From

Sample SiC Panel Design (Cont) Showing Rib Structure & Mount Locations

75CM SiC Hexagonal Mirror Substrate

1.25m SiC Outer Panel

Panel Performance Assessment Panel Performance & Figure Quality Forecast Weight < 300lbs Gravity Sag on 3 Points < < 4mM RMS Thermal Deformation < 4mM RMS Figure Quality Attainable 3.5mM RMS In The Next Period Revise Baseline Design Configuration To Maximize Compatability With Xinetics’ Capital Equipment Acquisition Plan Develop Composite FEA Model (SiC, Adhesive, Cladding) Compute Gravity Sag for 3 & 6 Points Supports; Isothermal & Gradient Thermal Deformations; Cladding Errors; Revise Error Budgets Explore Benefits/Regrets of Cathedral Ribs to Stiffen Intracell Facesheet Estimate Panel Cost

Panel Manufacturing Process Fabricate Mold Components & Tooling Free Abrasive Grind Clean Mold Parts after Machining Replication Make SiC Slip Assemble Mold Bipod Attachment Fill and Freeze Casting Leach Disposable Mold Parts Sublimation Drying Metrology / Testing Pre-Fire Pre-Fire Machining Blocking Body Siliconize Mount in Shipping Crate Mandrel Shape Generate Surface Shape

Initial Risk Assessment Magnitude of Thermal Deformations at –25C Disparate CTE’s Among Panel Components FEA Will Establish Criticality Forming & Replicating 2M Class Mirrors Will Not Have Been Done Before Start of CCAT Project Risk Reduction Activity Recommended Forecasting Impact on Optical Quality Caused By Replication Stress & Adhesive Shrinkage Quantify Adhesive Shrinkage With Test Pieces Use Stress Samples During Formation of Replication