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AURA’s road map to future 30m - 100m groundbased observatories - entering the “ era of the Giants ” in partnership. The New Initiatives Office - a partnership between Gemini, NOAO and our Communities. DRAFT – first thoughts (12/18/00) abbreviated version.
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AURA’s road map to future 30m - 100m groundbased observatories- entering the “era of the Giants” in partnership The New Initiatives Office - a partnership between Gemini, NOAO and our Communities DRAFT – first thoughts (12/18/00) abbreviated version
AURA’s “New Initiative Office”- a New Initiative for Groundbased Astronomy • Global context • Science Drivers (highly abbreviated in this version) • Organizing for success in partnership • Focusing on Innovation
Global context 2000 2010 Keck I&II Keck-Inter. ESO-VLTI NGST ALMA SIM VLA-upgrade UT1,UT2,UT3,UT4 Gemini N&S HET LBT LSST? CELT and maybe GSMT… OWL Phase A: of what? NIO timeline 2008 2000 2010 2015 The decade of adaptive optics The era of the “giants”
How we will be competitive from the ground • The “Next Generation” Space Telescope (NGST) will probably launch 2006 - 2010 • an 6m - 8m telescope in space • NGST will be extremely competitive for: • deep infrared imaging, • spectroscopy at wavelengths longer than 3 microns • Groundbased telescopes can still compete in the optical and near-infrared • moderate to high resolution spectroscopy • Groundbased facilities can also exploit large baselines • high angular resolution observations
“Deconstructing High z Galaxies” Integral field observations of a z = 1.355 irregular HDF galaxy (Ellis et al) “Starformation histories of physically distinct components apparently vary - dynamical data is essential” -- this is very hard on 8m – 10m telescopes
Log10 Fu (mJansky) x 30 Gemini 10 s, t = 10,000s R = 1800 l (mm) Going beyond Gemini Solar System @ 10 pc Jupiter 500 mas Gilmozzi et al (1998) Models for 1 MJ Planets at 10 pc from Burrows et al 1997
Observations at z = 2 - 5 1 - 10 milli- arcseconds Velocity dispersion R= 105 104 103 102 101 Imaging Spectroscopy 10 AU Galactic observations out to 1kpc at 10 mas resolution Going beyond 0.1 arcsecond astronomy requires resolution and sensitivity Flux 1 AU 1 R 100 AU 10 pc 100 pc 0.1 pc Accretion Disks Molecular Cloud Cores Mol. Outflows GMC Protoplanetary Disks AGN Jets/HH Planets Stellar Clusters
New Frontiers: Galaxies Dense sampling over large fields of view: Depth: to reach z=0.5-10 for dense sampling Capabilities Large aperture Telescope Large FOV (>20’) O/IR MOS at R~5000
Why a wide field Sensitivity + FOV* Large Scale Structure 100Mpc (5Ox5O), 27AB mag (L* z=9), dense sampling NBT 1.5 yr Gemini 50 yr NGST 140 yr *uniqueness cf. ESO 100m OWL
The NIO – organizing for success in partnership AURA External resources Steering Committee: Pres. AURA Dir. Gemini Dir. NOAO Another (S.Strom) NIO Advisory Committee Resources Resources Gemini NIO Office PM: J. Oschmann PS: (TBD) NIO staff (allocated FTE’s) NOAO Working Groups Study Contracts
Baseline Approach - ambitious at the outset • Diffraction limited telescope D ~ 30m - 100m • Operating wavelengths • Corrected Field of View • Uncorrected FOV 10 - 20 arcmins Tech. challenge 0.9mm - 3.8mm Science challenge Science challenge 1 arcmin - 3 arcmin Tech. challenge Tech. challenge • Minimize risk -- if at all possible • Focus on technologies that have the potential to produce the most innovative results • Multi-conjugate AO • Smart structures • Optical materials and support approaches • Analytical analysis of wind-buffeting • “Cheap” enclosures
New Initiative’s Office, a partnership between Gemini, NOAO and our Communities • Issues • Corrected vs. uncorrected FOV • Error Budget, Complexity • Strehl ratio vs. FOV vs. No. lasers • Cost of aspheric vs. spherical M1 • Wind buffeting analysis, the role of smart structures • Mauna Kea vs. Chajnantor • Narrow vs. Wide field, detectors • National vs. International support • Working Groups • Science • Systems • Adaptive Optics • Optics • Structures and Controls • Sites • Instrumentation • Management
Mirror-to-cell actuators Integrated mirror/cell segment Large stroke actuators Mirror support truss with smart structure elements/active damping as needed Possible Concept • A “radio telescope” married to active and adaptive optics Three levels of figure control: • Each mirror segment • is controlled within an individual cell • Each cell is then controlled with respect to the primary mirror support structure • The support structure may have to use “smart structure” technology to maintain sufficient shape and/or damping for slewing/tracking
A proposed approach to achieving the image quality science goals LGSs provide full S.C. Deformable M2 : First stage MCAO, wide field seeing improvement and M1 shape control • Wide and narrow field science multiplexing • M2: rather slow, large stroke DM to compensate ground layer and telescope figure, or to use as single DM at >3 m. (~20000 act) • Dedicated, small field (1-2’) MCAO system (~4-6DMs). Active primary (0.1Hz)? 10-20’ Field at 0.2-0.3” seeing 1-2’ field fed to the MCAO module Focal plane
How do we cost a 30 - 100m?Risk assessment examples 1 of 3 • Adaptive Optics • multiple-conjugate AO needs to be demonstrated • requires a laser solution • deformable mirror technology needs to expanded for 50m ( x 10 - 20 more actuators • How do we make “light-weight”, 2 - 4m aspheric segment mounted in its own active cell and can we afford hundreds of them? • How much dynamic range do we need to control cell-segment to cell-segment alignment ? • Will “smart”, and/or active damping systems have to be used telescope • evaluate by analysis and test. • Composites or Steel?
75m 75m 150m 150m An Enclosure for 50m -- “how big?” Risk assessment examples 2 of 3 • Restrict observing range to airmasses < 2.0 30 degrees • “Astro-dome” approach • Heretical proposition #1 - excavate • significantly lowers enclosure cost • further shields telescope from wind • reliant on AO to correct boundary layer • Heretical proposition #2 - perhaps the wind characteristics of a site are now more important than the seeing characteristics
Risk assessment examples 3 of 3 • Telescope Structure and wind loading • We need to characterize this loading in a way that is relatively easy to use in finite element analysis. This is easy, but mathematically intensive. Basically for each node that gets a wind force, a full vector of force cross spectra is generated, therefore the force matrix is a full matrix with an order equal to the number of forces (10’s of thousands). • Enclosure concept (do we need one)? • What concept can we afford both in terms of dollars/euros and environmental impact (note Heretical Proposition #2) • PROBABLE CONCLUSION: WE NEED A TECHNOLOGY TEST-BED • a 20m - 30m “new technology telescope” • this is probably to only way to establish a credible cost for a 50m - 100m diffraction limited optical/IR groundbased telescope
New Initiative’s Office, a partnership between Gemini, NOAO and our Communities • Working Groups • Science • Systems • Adaptive Optics • Optics • Structures and Controls • Sites • Instrumentation • Management Preliminary reports in draft form, community meetings and first design studies underway - Strategy Document by June 2001