Next Generation O/IR Telescopes

Stephen E. StromAssociate Director

GSMT Development

NOAO User’s CommitteeOctober, 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

Science with a GSMT: The SWG View

The physics of young Jupiter's

GSMT SWG Members

Chair: Rolf-Peter Kudritzki, UH IfAVice-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

Probing the Distant Universe

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

30m

8m

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, 3 limit at R=5,000

0.1”x0.1” IFU pixel(sub-kpc scale structures)

J H K 26.5 25.5 24.0

Connecting the Distant & Local Universe

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

Deconstructing Nearby Galaxies

Stellar Populations in Galaxies

M 32 (Gemini/Hokupaa) GSMT with MCAO

20”

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

3% 1 Gyr/[Fe/H]=0.0

35% 5 Gyr/[Fe/H]=0.0

62% 10 Gyr/[Fe/H]=-0.3

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

Input Simulation 30 m GSMT JWST

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; )

• Key requirements:– On axis, high Strehl AO; low emissivity

– Exploit near-diffraction-limited mid-IR performance

• Time to complete study with GSMT:– 2 years

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

Planet formation studies in the infrared (5-30µm):

Probe forming planets in inner disk regions Residual gas in cleared region low emission Rotation separates disk radii in velocity High spectral resolution high spatial resolution

Simulated 8 hr exposure

H2H2

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

Detecting and Characterizing Exo-Planets

Key Parameters: 30m GSMT

5 D Separation @ 10pc

1.2 40 mas 0.4 AU

4.7 160 mas 1.6 AU

Aperture is critical to enable separation of planet from stellar image

Exo-Jupiter Examples