GMTIFS – An AO-Corrected Integral-Field Spectrograph and Imager for GMT

transcript

GMTIFS – An AO-Corrected Integral-Field

Spectrograph and Imager for GMT

Peter McGregorThe Australian National University

AO-Corrected IFS

GMT 2010 Korea - 2010 October 4-6

Integral Field Unit SpectrographAdaptive Optics

GMT LTAO System GMTIFS

Δv = 60 km/sΔx = 6-50 mas

MOTIVATIONS

GMT 2010 Korea - 2010 October 4-6 3

Motivation - IFS

• AO-corrected integral-field spectroscopy was pioneered on 8-10m telescopes• NIFS on Gemini, SINFONI on VLT, OSIRIS on Keck• These have enabled “AO spectroscopy”

• It is now an essential feature on ~30 m telescopes• Imaging studies brightnesses, colors, morphology• Spectroscopy studies kinematics, excitation, physical processes

Motivation - GMT

• Deliver better angular resolution with Laser Tomography Adaptive Optics (LTAO)• Diffraction-limited FWHM on GMT is ~ 16 mas at 1.6 μm• Black-hole masses, protoplanetary disks• Diffraction-limited sampling, small FOV

• Collect more light from faint objects• Partial AO correction, but not diffraction limit• Galaxy dynamics: 0.05 arcsec sampling, 3 arcsec FOV

• GMTIFS will benefit in both these ways

GMTIFS – Overview

• Near-infrared; 1-2.5 μm• Single-object, AO-corrected, integral-field spectroscopy

• Primary science instrument• Two spectral resolutions: R = 5000 (Δv = 60 km/s) & 10000 (Δv = 30 km/s) • Range of spatial sampling and fields of view:

• Narrow-field, AO-corrected, imaging camera• Secondary science instrument• 5 mas/pixel, 20.4× 20.4 arcsec FOV• Acquisition camera for IFS

• NIR tip-tilt wave front sensor• 150 arcsec diam. guide field

• Flat-field and wavelength calibrationGMT 2010 Korea - 2010 October 4-6 6

Spaxel size (mas) 6 12 25 50

Field of view (arcsec) 0.54×0.27 1.08×0.54 2.25×1.13 4.5×2.25

GMTIFS on Instrument Platform

7GMT 2010 Korea - 2010 October 4-6

SCIENCE DRIVERS

GMT Science Drivers• Planets and Their Formation

• Imaging of exosolar planets• Radial velocity searches for

exoplanets• Structure and dynamics of proto-

planetary debris disks• Star formation and the initial mass

function• Stellar Populations and Chemical

Evolution• Imaging of crowded populations• Chemistry of halo giants in Local

Group galaxies

• Assembly of Galaxies• The mass evolution of galaxies• Chemical evolution of galaxies• Tomography of the inter-galactic

medium• Black Holes

• Mass determinations• Dark Energy and the Accelerating

Universe• Baryonic oscillations at z > 4• Supernovae at z > 1

• First Light and Reionization• The reionization era• First Light

Imaging of exosolar planets• Radial velocity searches for

exoplanets Structure and dynamics of proto-

planetary debris disks Star formation and the initial mass

Evolution Imaging of crowded populations• Chemistry of halo giants in Local

Group galaxies

• Assembly of Galaxies The mass evolution of galaxies Chemical evolution of galaxies• Tomography of the inter-galactic

Mass determinations• Dark Energy and the Accelerating

Universe• Baryonic oscillations at z > 4 Supernovae at z > 1

Imaging of exosolar planets• Radial velocity searches for

exoplanets Structure and dynamics of proto-

planetary debris disks Star formation and the initial mass

Evolution Imaging of crowded populations• Chemistry of halo giants in Local

Group galaxies

• Assembly of Galaxies The mass evolution of galaxies Chemical evolution of galaxies• Tomography of the inter-galactic

Mass determinations• Dark Energy and the Accelerating

Universe• Baryonic oscillations at z > 4 Supernovae at z > 1

SCIENCE DRIVER The Formation of Disk Galaxies at High Redshift

High-z Disk Galaxies

• Disk formation process• Rotational velocity vs velocity dispersion (Vrot/σ ~ 1-5 at z ~ 2)

• Mass accumulation history• Hα dynamics

• Star formation history• Hα luminosity

• Chemical abundance history• Rest-frame optical emission-line ratios

HUDF Chain Galaxies & Clump Clusters

ACS V ACS VNICMOS H NICMOS H

Clump ClustersChain Galaxies

Bulgeless

Elmegreen et al. (2008)

High-z Disk Galaxies

GMT 2010 Korea - 2010 October 4-6 15Elmegreen et al. (2009)

ClumpCluster

EarlyBulge

FlocculentSpiral

MatureSpiral

GDDS-22 2172 with NIFS

GMT 2010 Korea - 2010 October 4-6 16H

65831.0 arcsec

z = 1.563, 10 hr on Gemini North

Disk Galaxy at z=2.35; 6 x 900 s

GMTIFSsim simulation HUDF - i

Disk Galaxy at z=2.35; 6 x 900 s

Vrot σ

LineCentral

Intensity Continuum

Line Luminosities

Tresse et al. (2001) Erb et al. (2006)

NIRSPEC (K)SINFONI/OSIRIS + AOGMTIFS - detectableGMTIFS – not detectable

F(line) =3x10-17

erg/s/cm2

Hα 6563

[O II] 3727[O III] 5007

SCIENCE DRIVER Massive Nuclear Black Holes

Nuclear Black Holes

GMT 2010 Korea - 2010 October 4-6 21Graham (2008)

Nuclear Black Holes• High spatial resolution is required at high-mass end

• R = GMBH/σ2 ~ 10.8 pc (MBH/108 M☼)(σ/200 km/s)-2

~ 35.3 pc (MBH/109 M☼)(σ/350 km/s)-2

• H-band diffraction limit = 0.014"• 10 pc @ z = 0.04• 35 pc @ z = 0.15

• High spectral resolution is required at low-mass end• Probe 104-106 M☼ black holes in clusters• Velocity dispersions ~ 20-60 km/s => FWHM ~ 40-140 km/s• Requires R ~ 10,000 (Δv ~ 30 km/s) to detect presence of

black hole

High-Mass Black Holes

• How massive do MBHs get (> 109 M☼)?• MBH vs L and MBH vs σ give disparate results• What is the space density of MBHs?

> 5×109 M☼

from Karl Gebhardt

Stellar Velocity Dispersion

• Stellar absorption features• CO Δv=2 at ~ 2.3 μm• CO Δv=3 at ~ 1.7 μm• Ca II triplet at ~ 0.85 μm

Challenges of GMT Meeting - 2010 June 15-16 24

Watson et al. 2008, ApJ, 682, L21

Circumnuclear Gas Disks

Cygnus A Pα 1.876 μm: 2×109 M☼

Nuclear Star Clusters

GMT 2010 Korea - 2010 October 4-6 26Ferrarese et al. (2006)

Follow the black hole scaling relations

Low-Mass BlackHoles/Star Clusters

GMT 2010 Korea - 2010 October 4-6 27Scarlata et al. (2004)

SCIENCE DRIVER Protoplanetary Disks and Outflows from Young Stars

Protostellar Disks and Outflows

DG Tau – Integrated [Fe II] (2005)

• NIFS H band

• Inclination ~ 60°• > 5:1 jet aspect

• Launch radius expected to be ~ 1 AU

• 20 AU resolution with NIFS

• 3 AU resn. with GMT at diffraction limit

100 AU

1 yr at 200 km/s

Protoplanetary Disks & Outflows

• DG Tau jet with NIFS• [Fe II] 1.644 μm

• One stationary clump

• One moving clump• 0.2 arcsec in 13 months• 130 km/s

• We will see changes in ~ 1 month with GMT!

2007200620052004

DG Tau – Entrainment?-50 -100 -150

Bicknell (1984)

INSTRUMENT DESIGN

LGS WFS

NGS WFS

GMTIFS Light Paths

AO WFSs GMTIFS

NIR NGS WFS

F-converters

Imager

Calibration Dichroic

OptLGSNIR

Maximal Cryostat Design

NIR WFS Feed

Tertiary

DichroicWindow

Compensator

Field lens

Beam-steering mirror

Tip-tilt wave-frontsensor

Fore-Optics Layout

Science fold mirror

Rotating cold-stop mask

Imager Layout

Atmospheric DispersionCorrector

Imager feedImager filterwheels

Imager utilitywheel

Imager detectorand focus stage

IFS Layout

IFS mask wheelIFS anamorphic focal ratio converters

IFS filterwheel

IFS Layout

IFS detectorand focus stage

IFS image slicer

IFS pupil mirrors

IFS field mirrors IFS collimator

IFS grating wheel and steering mirrors

Optics – Trimetric View

Calibration system

Calibration feed mirror

Calibration Subsystem

LTAO wave-front sensors

GMTIFS calibration system GMTIFS cryostat

SYNERGIES

JWST Comparison

• Integral-Field Spectroscopy:• GMTIFS will have higher spectral resolution (R = 5000-10000 vs

2700)• AND higher spatial resolution (≤ 50 mas vs 100 mas)• AND GMTIFS may have lower read noise (??? vs ~ 5 e)

• GMTIFS will address broader science

• Imaging:• JWST will out-perform GMTIFS for imaging targets with 6.5 m

diffraction-limited resolution (85 mas @ K)• GMTIFS’s advantage is in observations requiring higher spatial

resolution (22 mas @ K)• Crowded fields, morphology, size measurement

• GMTIFS will do different science

Summary

• GMTIFS will be a general-purpose AO instrument for GMT

• It will address many of the key science drivers for GMT

• It will be competitive with similar instruments on other ELTs• (within certain caveats)

• It will fully utilize the LTAO capabilities of GMT

• It may be able to address key science (galaxy evolution) without phasing the seven M1 segments

GMTIFS – An AO-Corrected Integral-Field Spectrograph and Imager for GMT

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