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Next Generation O/IR Telescopes. Stephen E. Strom Associate Director GSMT Development NOAO User’s Committee October, 2005. Outline. US Decadal Survey perspective AURA New Initiatives Office Science with a GSMT Top level summary of ELT Projects: OWL, GMT & TMT Overview of TMT
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Next Generation O/IR Telescopes Stephen E. Strom Associate Director GSMT Development NOAO User’s Committee October, 2005
Outline • US Decadal Survey perspective • AURA New Initiatives Office • Science with a GSMT • Top level summary of ELT Projects: OWL, GMT & TMT • Overview of TMT • Site Selection • Status of AURA/NSF support of TMT and GMT
AASC Vision for GSMT “The Giant Segmented Mirror Telescope (GSMT), the committee’s top ground-based recommendation….is a 30-m-class ground-based telescope that will be a powerful complement to NGST [and ALMA] in tracing the evolution of galaxies and the formation of stars and planets.”
Giant Segmented Mirror Telescope • 30m segmented primary mirror • 10x gain in light gathering power • Diffraction limited via Adaptive Optics (AO), • 3x gain in angular resolution • For (typical) background limited problems, time to reach fixed S/N reduced by 100x (point source)
A New Paradigm “GSMT requires a large investment of resources and offers an opportunity for partnership between national and university/independent observatories in producing and operating a world-class facility within the coordinated system of these two essential components of US ground-based astronomy.” “Half the total cost should come from private and/or international partners.”
AURA Response to AASC Challenge • In response, AURA formed a New Initiatives Office (NIO) to support scientific & technical studies to evaluate technical risk areas & cost of building a GSMT • NIO has been a joint venture of NOAO + Gemini
AURA-NIO Goals • Ensure community access to highly-capable next generation ELTs by enabling completion of • “Fast track” facilit(ies) contemporary with JWST/ALMA • “Ultimate” ground-based OIR observatory before 2025 • Develop partnerships to build and operate ELTs • Engage and involve the community at all phases • Design • Construction (instruments and key subsystems) • Operation • Look a decade ahead and begin dialog re next generation facilities
NIO Activities to Date • Identify key science drivers for a 30m-class ELT • Accomplish via a community-based GSMT SWG • Carry out technical studies common to all ELTs • AO; wind loading; segment fabrication; sites • Develop a ‘point design’ • Understand systems issues • Estimate system and subsystem costs • Results summarized in “GSMT Book” • http://www.aura-nio.noao.edu/book/index.html • Provide engineering support as part of TMT collaboration
GSMT Science Working Group - Identify forefront astrophysical science likely to emerge over next decade - Identify science potentially enabled by GSMT - Understand and assess design options that can achieve science - Identify technologies to be advanced or developed - Provide advice the NSF about investments needed - Advocate community interests in private/public partnerships • Establish working relationships with groups in Australia, Canada, • Europe, Japan, Mexico - Keep abreast of progress on TMT and GMT to ensure that emerging designs + instrument suites meet community aspirations
The physics of young Jupiter's Science with a GSMT: The SWG View
GSMT SWG Members Chair: Rolf-Peter Kudritzki, UH IfA Vice-Chair: Steve Strom, NOAO SWG Members: • Jill Bechtold -- UA • Mike Bolte -- UCSC • Ray Carlberg -- U Toronto • Matthew Colless -- ANU • Irena Cruz-Gonzales -- UNAM • Alan Dressler -- OCIW • Betsy Gillespie -- UCI • Michael Liu -- UHIfA • Kim Venn -- U Victoria • Terry Herter -- Cornell • Paul Ho -- CfA • Jonathan Lunine -- UA LPL • Claire Max -- UCSC • Chris McKee -- UCB • Francois Rigaut -- Gemini • Doug Simons -- Gemini • Chuck Steidel -- CIT
Science Enabled by GSMT • Tomography of the Intergalactic Medium at z > 3 • High resolution spectra of IGM absorption spectra • Determine 3-dimensional distribution of gas • Track evolution of metal abundance & relate to galactic activity • Observing the galaxy assembly process • Integral field unit spectra of pre-galactic fragments • Determine gas and stellar kinematics; measure mass directly • Quantify star formation activity and chemical composition • Separating constituent stellar populations in galaxies • MCAO imaging and spectroscopy • Determine age and distribution of chemical abundances • Understanding where and when planets form • Ultra-high resolution mid-IR spectra of ~1000 accreting PMS stars • Infer planetary architectures via observation of ‘gaps’ in disks • Detecting and characterizing mature planets • Extreme AO coronography; spectroscopy
IGM Tomography • Goals: • Map out large scale structure for z > 3 • Link emerging distribution of gas; galaxies to CMB • Determine metal abundances • Measurements: • Spectra for 106 galaxies (R ~ 2000) [wide-field 8-m?] • Spectra of 105 QSOs and galaxies (R ~20000) • Key requirements: • 15-20’ FOV; ~1000 fibers • Time to complete study with GSMT: 3 years
The Potential of GSMT Input 8m 30m
Analyzing Galaxies at High Redshift • Determine the gas and stellar dynamics within • individual galaxies • Quantify variations in star formation rate • Tool: IFU spectra • [R ~ 5,000 – 10,000] GSMT 3 hour, 3s limit at R=5,000 0.1”x0.1” IFU pixel (sub-kpc scale structures) J H K 26.5 25.5 24.0
Stellar Populations • Goals: • Quantify ages; [Fe/H]; for stars in nearby galaxies spanning all types • Use ‘archaelogical record’ to understand the assembly process • Quantify IMF in different environments • Measurements: • CMDs for selected areas in local group galaxies • Spectra of stars in selected regions (R ~ 1000) • Key requirements: • MCAO delivering 30” FOV; MCAO-fed NIR spectrograph • Time to complete study with GSMT: 3 years
Stellar Populations in Galaxies 20” M 32 (Gemini/Hokupaa) GSMT with MCAO JWST Population: 10% 1 Gyr ([Fe/H]=0), 45% 5 Gyr ([Fe/H]=0), 45% 10 Gyr ([Fe/H]=-0.3) Simulations from K. Olsen and F. Rigaut
Crowding Limits Photometric Accuracy Crowding introduces photometric error through luminosity fluctuations within a single resolution element of the telescope due to the unresolved stellar sources in that element.
Crowding Limits for GSMT JWST limit GSMT limit Limiting luminosity scales as ~ D-2
Modeling Population Mixes • Maximum likelihood method of Dolphin (1997) • 45 model isochrones with ages from 0.5 - 13 Gyr and [Fe/H]=0.0,-0.3,-0.6 compared with data
Recovering Population Mixes 30 m GSMT Input Simulation JWST 2% 1 Gyr/[Fe/H]=0.0 34% 5 Gyr/[Fe/H]=0.0 64% 10+/-1 Gyr/[Fe/H]=-0.3 5% 0.5--1 Gyr/[Fe/H]= -0.6 -- 0.0 15% 3--7 Gyr/[Fe/H]=0.0 80% 9--13 Gyr/[Fe/H]=-0.3 -- 0.0 3% 1 Gyr/[Fe/H]=0.0 35% 5 Gyr/[Fe/H]=0.0 62% 10 Gyr/[Fe/H]=-0.3
Origins of Planetary Systems • Goals: • Understand where and when planets form • Infer planetary architectures via observation of ‘gaps’ • Measurements: • Spectra of 103 accreting PMS stars (R~105; l ~ 5m) • Key requirements: • On axis, high Strehl AO; low emissivity • Exploit near-diffraction-limited mid-IR performance • Time to complete study with GSMT: • 2 years
Planet formation studies in the infrared (5-30µm): • Probe forming planets in inner disk regions • Residual gas in cleared region low t emission • Rotation separates disk radii in velocity • High spectral resolution high spatial resolution Probing Planet Formation with High Resolution Infrared Spectroscopy S/N=100, R=100,000, > 4m Gemini out to 0.2kpc 10s of objects GSMT 1.5kpc 1000s of objects JWST N/A Simulated 8 hr exposure
Detecting and Characterizing Exo-Planets Goal: Image and characterize exo-planets • Mass, radius, albedo • Atmospheric structure • Chemistry • Rotation Measurements: R~ 10 photometry & R ~ 200 spectra • Near-infrared (reflected light) • Mid-infrared (thermal emission) Role of GSMT: Enable measurements via • High sensitivity • High angular resolution
Key Parameters: 30m GSMT Aperture is critical to enable separation of planet from stellar image