1 The Thirty-Meter Telescope Project: Design and Development Phase Larry Stepp and Stephen Strom AURA New Initiatives Office GSMTCELTVLOT

2 Outline The TMT Partnership The next step: TMT Design and Development Phase Conceptual design process Technology development activities Site testing program Conclusions

3 Goals of TMT Partnership Combine the strengths of public and private observatories to create a 30-m diffraction-limited telescope –Contemporary with JWST/ALMA –Following the recommendation of the AASC decadal review Public access through peer review Involve the community in defining observatory goals Work with other ELT programs to maximize community benefit from available development funds

4 Proposed Partnership AURA Board of Directors CELTACURA Letters of Intent have been signed by each institution.

5 Project Will Be Fully Integrated Strong project scientist who helps guide all engineering decisions Strong project manager responsible for performance, budget and schedule –Budget and schedule contingency controlled by project manager Emphasis on systems engineering Design-to-life-cycle-cost approach Formal, rigorous design reviews A product-oriented WBS –Reflected in organization of the project team

6 TMT Project Organization

7 The next step: TMT Design and Development Phase

8 Top-level Schedule ALMA OperationsJWST Launch D&D Phase

9 Conceptual Design Process: System Architecture Issues

10 Comparison of Point Designs GSMTCELTVLOT cnrc.gc.ca/VLOT/index.html

11 Comparison of Point Designs Design FeatureGSMTCELTVLOT Optical DesignCassegrainRitchey-Chrétien Aperture StopAt secondary mirrorAt primary mirror M1 Diameter30 m 20 m M1 Focal RatioF/1.0F/1.5F/1.0 Segment Size1.33 m across corners1.0 m across corners1.8 m across corners Segment Thickness50 mm45 mm80 mm Number of Segments M2 Diameter2 m3.96 m2.5 m M2 ConfigurationAdaptiveActive Final Focal RatioF/18.75F/15 Telescope StructureAlt-Az: radio telescopeAlt-Az: large elevation journals Elevation axisBelow primaryAbove primaryBelow primary Instrument LocationsPrime Focus Cassegrain Focus Fixed-gravity Cass. Nasmyth (MCAO relay) NasmythVertical Nasmyth (fixed gravity orientation)

12 Key Design Decisions Primary mirror focal ratio Segment configuration, size & thickness Segment material Adaptive vs active secondary Gregorian vs Cassegrain secondary Nasmyth only vs multiple foci –Principal instrumental requirements on telescope Location of elevation axis: above vs below primary AO modes to be included; –Division of AO between telescope and instruments Configuration of enclosure

13 Conceptual Design Process Design trade studies consider performance, cost & risk –Performance evaluated by simulations and integrated modeling –Operations modeling used to consider effect of observing modes on scientific output and cost –Costs evaluated by parametric cost estimating –Science return evaluated using observing scenarios and quantitative figures of merit Trade studies performed by project team with help from consultants and industry Instrument conceptual designs developed by competing teams from observatories, universities or industry

14 Technology Development Activities

15 Adaptive Optics Technology development needed to support five AO modes: –Mid-IR, low emissivity NGS AO –MCAO –GLAO –ExAO –MOAO

16 Key AO Technology Developments MIRAOMIRAO MCAOMCAO GLAOGLAO ExAOExAO MOAOMOAO Improved analysis & simulation methods Adaptive secondary mirrors Other large adaptive mirrors MOEMS deformable mirrors Laser guidestar beacons Large-format, fast, low noise detectors Site testing of C N 2 distribution Cryogenic deformable mirrors Focal plane wavefront sensing Wavefront rec. & fast signal processors Required Development Possibly Required

17 Instrumentation Need for technology investment: Component cost & availability constrains instrument feasibility Early investment reduces cost and risk

18 Instruments Under Consideration Wide-field optical spectrograph Million-element IFU spectrograph High resolution optical spectrograph GLAO-fed near-IR MOS/IFU MCAO-fed near-IR imager MCAO-fed deployable IFU spectrograph Extreme AO coronagraph Near-IR Echelle spectrograph Mid-IR Echelle spectrograph Mid-IR imager/low resolution spectrograph

19 Summary of Instrumentation Technology Development Optical Detectors Near-IR Detectors Mid-IR Detectors Immersed Silicon Grisms Large Mosaic Gratings VPH Gratings Integral Field Units Large Cryo. Filters Sol-gel AR Coatings MEMS Slit Masks Wide-field optical spect. Million-element IFU spectrograph HR optical spectrograph GLAO-fed near-IR MOS/IFU MCAO-fed near-IR imager MCAO-fed deployable IFU spectrograph Extreme AO coronagraph Near-IR Echelle spect. Mid-IR Echelle spect. Mid-IR imager/low res. spectrograph Tech Dev Needed

20 Other Key Development Areas Investigate advanced structural approaches Stressed-mirror polishing on CP machine 3.66 m CP machine by CEBA Corp.

21 Other Key Development Areas Investigate advanced structural approaches Stressed-mirror polishing on CP machine 75-cm lightweight segment Alternate segment materials: SiC

22 Other Key Development Areas Investigate advanced structural approaches Stressed-mirror polishing on CP machine Alternate segment materials: SiC Analyze wind buffeting effects

23 Other Key Development Areas Investigate advanced structural approaches Stressed-mirror polishing on CP machine Alternate segment materials: SiC Analyze wind buffeting effects Develop integrated modeling tools High-performance durable coatings Software architecture Operations modeling

24 Site Evaluation

25 TMT Site Evaluation Program Remote sensing Wind CFD SimulationsWeather stations Seeing and C N 2 Site choice is a key element in overall system performance –AO performance –Atmospheric transmission –Structure, enclosure and controls systems implications Delivered science is closely linked with site characteristics Site selection is on the critical path for TMT

26 Key Requirements Uniform evaluation information + data for multiple sites –Cloud cover –Precipitable water vapor –Long-term weather patterns –Wind flow and turbulence modeling –In situ measurements of temperature; wind –Ground-layer and upper atmospheric turbulence measurements –Seismicity and geotechnical characteristics –Light pollution; demographic and ownership issues These data are essential to inform a site choice for any ELT

27 Remote Sensing Studies Objective evaluation of transparency and PWV Place current conditions in context of long-term patterns

28 Cloud cover at Selected Chilean Sites Fraction of time that sky cover conditions are clear (photometric) and transitional (spectroscopic) for the observing night.

29 Monitoring Atmospheric Turbulence MASS-DIMMs will be operating on 6 sites by 2004

30 C n 2 Profile from MASS Campaign Courtesy Andrei Tokovinin

31 DIMM and MASS Results Courtesy Andrei Tokovinin

32 Computational Fluid Dynamics Characterize wind flow to allow pre-selection of sites –Wind intensity –Turbulence characteristics –Down-wind wakes Characterization of Chilean sites well underway Analysis of other sites to be completed by Q Turbulent kinetic energy in air flow over Magellan site at Las Campanas Observatory Courtesy Konstantinos Vogiatzis Wind

33 Other TMT-Related Papers in this Workshop Richard Dekany, Exo-Earth Study with CELT René Doyon, Detecting and Characterizing Exo-planets using Multi-Color Detector Arrays Jerry Nelson et al, California Extremely Large Telescope Dennis Crabtree, An Overview of the Canadian VLOT Project Jeremy Mould, GSMT George Angeli, Robert Upton, Brooke Gregory, Brent Ellerbroek and Anna Segurson, Active Optics for a Giant Segmented Mirror Telescope Scott Roberts, John Pazder, Nathan Loewen, Joeleff Fitzsimmons, and Raymond Yu, Integrated Modeling of the Canadian Very Large Optical Telescope Konstantinos Vogiatzis and David S. DeYoung, Numerical Simulations of Flow in Extremely Large Telescope Enclosures Joeleff Fitzsimmons, Glen Herriot, Laurent Jolissaint, John Pazder, Scott Roberts, Mahmoud Mamou, and Kevin Cooper, Aerodynamic Modeling of the Canadian Very Large Optical Telescope

34 Other TMT-Related Papers in this Workshop Gary Chanan, Issues in Segment Alignment for Extremely Large Telescopes Don Gavel, Sodium Laser Guidestar Adaptive Optics: Lessons Learned Laurent Jolissaint, Jeffrey A. Stoesz, and Jean-Pierre Veran, Wide Field Adaptive Optics for Large Optical Telescopes: Upper Bound on Performance Brent Ellerbroek, Wavefront Reconstruction Algorithms and Simulation Results for Multi-Conjugate Adaptive Optics on Giant Telescopes Andrei Tokovinin, Sensing and Compensation of Ground-layer Turbulence at ELTs Mark Chun, Site Characterization at Mauna Kea for an ELT Konstantinos Vogiatzis and David S. DeYoung, Site Characterization through the Use of Computational Fluid Dynamics John Pazder, Laurent Jolissaint, Scott Roberts, and Malcolm Smith, The Optical Modeling Tools for the Canadian Very Large Optical Telescope Integrated Model Laurent Jolissaint and Jean-Pierre Veran, PAOLA, an Analytic Code for Fast and Accurate Astronomical Adaptive Optics Performance Studies

35 Current Status of TMT Project Proposals submitted to a private foundation & CFI; AURA proposal to NSF ready to submit Interim Board of Directors meeting monthly Science Advisory Committee meeting monthly –Developing Science Requirements Document Interim Steering Group meeting monthly, telecons weekly Advertisements placed for Project Manager –Send resumes to:TMT Search Committee c/o Stacey Scoville California Institute of Technology 1200 East California Boulevard Mail Code Pasadena, CA 91125, USA

36 Key Activities for Immediate Start We are initiating long-lead-time activities that will drive the conceptual design choices over the next 30 months: –Site testing –Develop stressed-mirror polishing techniques –Develop lightweight SiC mirror blanks –Model dynamic disturbances caused by wind –Develop large adaptive mirrors –Initiate AO development strategy –Develop durable coatings –Investigate designs for seeing-limited instruments to understand their impact on the telescope design

37 Conclusions We are launching the TMT D&D Phase Goal is to have CoDR in 30 months –Evaluate design options and costs –Develop needed technology –Evaluate potential sites –Select optimal design, define associated cost TMT goal is to have first light with all segments in 2014