Transcript Instruments and Detector Systems for TMT Rebecca Bernstein, UCSC Detectors For Astronomy ESO 12 Oct 2009 TMT Keck.

Instruments and Detector Systems for TMT
Rebecca Bernstein, UCSC
Detectors For Astronomy
ESO
12 Oct 2009
TMT
Keck
Instruments and Detector Systems for TMT
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Motivation for ELTs — Science science science
— Why science scales with aperture (with & without AO)
— Illustrative science cases
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The TMT project
— Brief design status
— Performance challenges
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“Early-light” TMT instruments: overviews & detector requirements
— NFIRAOS (Narrow Field IR AO System)
— IRIS
(IR Imager & Spectrograph)
— WFOS/MOBIE (Wide Field Opt. Spec./Multi-Object Broadband Imaging Echellette)
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — why science scales with aperture
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Sensitivity (= 1/ time needed to get to a given signal to noise)
— Enables: fainter, higher spectral resolution  more targets, more distant, more info.
sensitivity 
— “seeing” limit:
D2

2
(In the background dominated regime!)
 ~ seeing ~ 0.3–1.0 arcsec
[optical to near-IR]

Atmospheric turbulence introduces wavefront
and image quality degradations.
Object’s light is
spread over
2 pixels
(Credit: Claire Max, UCSC)
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — why science scales with aperture
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Sensitivity (= 1/ time needed to get to a given signal to noise)
— Enables: fainter, higher spectral resolution  more targets, more distant, more info.
sensitivity 
— “seeing” limit:
D2

2
(In the background dominated regime!)
 ~ seeing ~ 0.3–1.0 arcsec
[optical to near-IR]

Atmospheric turbulence introduces wavefront
and image quality degradations.
Object’s light is
spread over
2 pixels
12 OCT 2009
Instruments and Detectors for the TMT
4
Motivation — why science scales with aperture
•
Sensitivity (= 1/ time needed to get to a given signal to noise)
— Enables: fainter, higher spectral resolution  more targets, more distant, more info.
sensitivity 

— “seeing” limit:
— diffraction limit:
D2

2
(In the background dominated regime!)
 ~ seeing ~ 0.3–1.0 arcsec
 ~ (1.2 /D)
Atmospheric turbulence introduces wavefront
and image quality degradations.
In principal, wavefront sensor/corrector can
measure compensate by measuring the errors
using a reference star.
* Fraunhoffer diffraction: 84% of light into first Airy ring.
[Ignoring Strehl ratio]
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — why science scales with aperture
•
Sensitivity (= 1/ time needed to get to a given signal to noise)
— Enables: fainter, higher spectral resolution  more targets, more distant, more info.
sensitivity 

— “seeing” limit:
— diffraction limit:
D2

2
(In the background dominated regime!)
 ~ seeing ~ 0.3–1.0 arcsec
 ~ (1.2 /D)
(Credit: VLT)
Atmospheric turbulence introduces wavefront
and image quality degradations.
In principal, wavefront sensor/corrector can
measure compensate by measuring the errors
using a reference star.
*Fraunhoffer diffraction: 84% of light into first Airy ring.
[Ignoring Strehl ratio]
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — why science scales with aperture
•
Sensitivity (= 1/ time needed to get to a given signal to noise)
— Enables: fainter, higher spectral resolution  more targets, more distant, more info.
sensitivity 
D2

2
(In the background dominated regime!)
— “seeing” limit:
 ~ seeing ~ 0.3–1.0 arcsec
background limited
 Sensitivity ~ D2
— diffraction limit:
 ~ (1.2 /D)
background limited
 Sensitivity ~ D4
— Extreme AO:
 ~ (1.2 /D)
background suppressed
 Sensitivity ~ D6

* Fraunhoffer diffraction: 84% of light into first Airy ring. [Ignoring Strehl ratio]
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the distant universe (high redshift)… Conversion of H  stars
Small star forming regions high redshift
(This one: gravitationally lensed)
(Credit: C. Steidel)
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the distant universe (high redshift)… galaxy formation
HST images of galaxies (1.5 < z < 2). Note
complex morphologies!
(Credit: C. Steidel)
12 OCT 2009
Integral-field spectroscopy
footprint
(Credit: J. Larkin)
Instruments and Detectors for the TMT
Goal:
dynamics, gas-phase abundances,
star formation rates
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the distant universe (high redshift)… galaxy formation
HST images of galaxies (1.5 < z < 2). Note
complex morphologies!
(Credit: C. Steidel)
12 OCT 2009
Integral-field spectroscopy
footprint
(Credit: J. Larkin)
Instruments and Detectors for the TMT
Goal:
dynamics, gas-phase abundances,
star formation rates
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the nearby universe (low redshift)… dynamics near black holes
4–10m + AO: Constraints on mass and dynamics at center of Milky Way
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the nearby universe (low redshift)… dynamics near black holes
4–10m + AO: Constraints on mass and dynamics at center of Milky Way
~30m +AO: Density distributions, better black hole masses & radii, relativitistic effects
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
In the nearby universe (low redshift)… image planets & planetary disks
(Credit: Nijita, NOAO group)
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
And everything in between …
Structure formation since the big bang
N-body simulation of dark matter
(and hydrogen with it) clustering
in the universe…
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Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
And everything in between …
Structure formation since the big bang
Background sources are used to “probe”
the intergalactic medium
12 OCT 2009
Instruments and Detectors for the TMT
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Motivation — Illustrative science cases
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Sensitivity: fainter, higher resolution
And everything in between …
Structure formation since the big bang
There are more faint probes than bright.
fainter
12 OCT 2009
Instruments and Detectors for the TMT
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The TMT project — brief design overview
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Configuration:
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30m filled-aperture
1.44 m segments (492 total)
F/1 primary
Secondary convex
F/15 focal plane
Elevation axis in front of the primary
Nasmyth instruments only
FOV: 20 arcmin
Pixel scale: 2.2 mm/arcsec
Wavelength 0.3 – 28 µm
Zenith Angles: 1°–65°
Seeing-limited in optical
Diffraction-limited (AO) in IR
12 OCT 2009
Instruments and Detectors for the TMT
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The TMT project — brief design overview
LGSF launch telescope
M2 support tripod
M2 structural hexapod
Tensional members
LGSF beam transfer
M2 hexagonal ring
NFIRAOS
M2 support columns
IRIS
MOBIE
Nasmyth
platform
Elevation journal
Laser room
12 OCT 2009
Azimuth cradle
M1 cell
Instruments and Detectors for the TMT
Azimuth truss
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The TMT project — brief design overview
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First decade instrument suite:
12 OCT 2009
Instruments and Detectors for the TMT
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The TMT project — brief design overview
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Secondary: 3.0m convex
Tertiary: 3.5m flat
Laser guide star system: launch telescope on back of M2 structure
12 OCT 2009
Instruments and Detectors for the TMT
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The TMT project — brief design overview
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Calotte Enclosure: mechanical and optical impact
Wind speed contours with 100% vents open
(flow along x-axis, Uo ~ 5 m/s)
12 OCT 2009
Instruments and Detectors for the TMT
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The TMT project — Performance challenges
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Example of performance challenge: wind-disturbance rejection
— dynamic response analysis: critical (and new!)
— Lowest vibrational mode are okay, but amplitude of modes = problem
— Stability depends on: wind power spectrum + structure
• M2: big flag out in the wind = problem.
Wind through opening
Dome seeing
M2 buffeting
M1 seeing
M1 buffeting
Wind through vents
12 OCT 2009
“Artistic”and
credit:
J. Nelson
Instruments
Detectors
for the TMT
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“Early-light” instruments — NFIRAOS — overview
NFIRAOS = Narrow Field IR AO System
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Multi-Conjugate AO (MCAO) System
Laser Guide Star (LGS) Facility
Feeds 1 of 3 instruments at one time
2 arcmin field of view
12 OCT 2009
Instruments and Detectors for the TMT
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NFIRAOS — overview
Future (third) Instrument
NFIRAOS Enclosure
Service Platform
Optics Bench and
Instrument Support
Structure
BTO Path
LGS WFS Optics
Nasmyth Platform
Interface
IRIS
Electronics Enclosure
Nasmyth Platform
12 OCT 2009
Instruments and Detectors for the TMT
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NFIRAOS — overview
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Multi-Conjugate AO (MCAO)
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3-D turbulence correction
2 Deformable Mirrors (DMs)
Actuator sampling: 64x64, 73x73
800 Hz, 38000x7000 control problem
Telescope
Deformable Mirrors
Wavefront
(DMs)
sensors
Multiple
guide stars
12 OCT 2009
Atmospheric turbulence
Control Algorithms
Instruments
for the TMT
“layers” and Detectors Processors,
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NFIRAOS — overview
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Laser Guide Star (LGS) Facility
— Na laser generates a “star” (at =0.589 mm) anywhere in the sky
• Rayleigh scatter at ~20 km
• Resonant scatter at 90-100 km
Keck and
Gemini
12 OCT 2009
LGS AO: Galactic Center
(Note Diffraction Rings)
Instruments and Detectors for the TMT
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NFIRAOS — overview
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Laser Guide Star (LGS) Facility
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150 Watt power
6 spots (25 Watts each): 1 central, 5 perimeter
Laser launch telescope behind M2
Within azimuth structure
Conventional optics for beam transport
Keck and
Gemini
12 OCT 2009
Instruments and Detectors for the TMT
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NFIRAOS — Detector Requirements
For Natural Guide Star (NGS) mode:
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Sub-apertures
Number of pixels:
Pixel size
Frame Rate
Read noise
QE:
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Prototype effort: [basis for design specs above]
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60x60 pupil sampling (0.5m diam, sq. grid, 3000 within pupil)
256x256 (60x60 sub-apertures, 4x4 pixels each)
21 µm
50 – 800 Frames Per Second
0.5-1.5 e75-90% <0.9µm, but 50-20% at 0.95–1µm
160x160 pixel CCID-56b developed by Keck and MIT/LL under TMT-AODP funding
Using 64 read channels
0.1 to 1.5 MHz pixel read rate
1-stage planar JFET amplifier
— To achieve 500 FPS with a 256x256, need 0.5 MHz pix read rate in 64 channels.
12 OCT 2009
Instruments and Detectors for the TMT
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NFIRAOS — Detector Requirements
For Laser Guide Star (LGS) mode:
“Polar Coordinate CCDs” (Matched to LGS elongation)
60x60 pupil sampling (0.5m diam, sq. grid, 3000 within pupil)
60x60 x [?x?] ~ 130k to 325k (6x6, center of pupil; 15x6, edge)
???
~800 FPS (corresponds to 500 µsec / pix = 2 KHz pix read rate)
3 e- at 800 FPS
90% at 0.589µm
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*Array Geometry
Sub-apertures
Number of pixels:
Pixel size
Frame Rate
Read noise
QE:
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Prototype effort: [basis for design specs above]
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160x160 CCID-56b developed by Keck and MIT/LL under AODP funding
Basis for design specs
128 video outputs
3.5 MHz pixel read rate
planar JFET amplifier
— To achieve 500 FPS with ~325k pixels, need 1.2 MHz pix read rate in 128 channels
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NFIRAOS — Detector Requirements
Fewer illuminated pixels reduces
pixel read rates and readout noise
sodium layer
ΔH =10km
H=100km
D = 30m
 Elongation  3-4”
LLT
TMT
AODP Design
12 OCT 2009
Instruments and Detectors for the TMT
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NFIRAOS — Detector Requirements
For Laser Guide Star (LGS) mode:
“Polar Coordinate CCDs” (Matched to LGS elongation)
60x60 pupil sampling (0.5m diam, sq. grid, 3000 within pupil)
60x60 x [?x?] ~ 130k to 325k (6x6, center of pupil; 15x6, edge)
(21 µm ?)
~800 FPS (corresponds to 500 µsec / pix = 2 KHz pix read rate)
3 e- at 800 FPS
90% at 0.589µm
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*Array Geometry
Sub-apertures
Number of pixels:
Pixel size
Frame Rate
Read noise
QE:
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Prototype effort: [basis for design specs above]
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160x160 CCID-56b developed by Keck and MIT/LL under AODP funding
128 video outputs
3.5 MHz pixel read rate
planar JFET amplifier
— To achieve 500 FPS with ~325k pixels, need 1.2 MHz pix read rate in 128 channels
12 OCT 2009
Instruments and Detectors for the TMT
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“Early-light” TMT instruments — IRIS — overview
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PI, Lenslet IFS: James Larkin (UCLA)
Co-PI, Slicer IFS: Anna Moore (CIT)
Project Scientist: Betsy Barton (UCI)
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Science Team:
Betsy Barton (UCI)
Maté Adamkovics (UCB)
Aaron Barth (UCI)
Joshua Bloom (UCB)
Pat Coté (HIA)
Tim Davidge (HIA)
Andrea Ghez (UCLA)
David Law (UCLA)
Shri Kulkarni (CIT)
Jessica Lu (CIT)
Hajime Sugai (Kyoto U)
Jonathan Tan (U. Florida)
Shelley Wright (UCI)
12 OCT 2009
Instruments and Detectors for the TMT
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IRIS — overview
IRIS = IR Imaging Spectrograph
• Behind NFIRAOS = diffraction limited
• On-Instrument WFS (deployable)
NFIRAOS MCAO system(Enclosure at -30C)
OIWFS dewar at 30C
— Correct field piston, tip/tilt
— Feed back to NFIRAOS
F/15 AO
Focus
Imager Filter
Wheels
IRIS dewar
(at 77K)
Grating
Common
spectrograph
and camera
for both IFUs
12 OCT 2009
Instruments and Detectors for the TMT
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IRIS — overview
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Spectrograph
— = 0.8-2.4 µm
— Spectral Resolution > 3500
— Lenslet (1282) Integral Field Unit:
• 0.004 or 0.010 arcsec/pix
• 5% of bandpass per exp.
• Best wavefront correction
— Slicer
• 90 slices, 2:1 aspect ratio
• 0.025 or 0.05 arcsec/pix
• Highest throughput
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NFIRAOS MCAO system(Enclosure at -30C)
OIWFS dewar at 30C
Imager Filter
Wheels
IRIS dewar
(at 77K)
Imager
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= 0.8-2.4 µm
FOV = 15 arcsec
0.004 arcsec/pix
Wavefront Error < 30 nm
Distortion error <0.050 arcsec.
Atmospheric Dispersion < 1 milliarcsec
12 OCT 2009
F/15 AO
Focus
Grating
Common
spectrograph
and camera
for both IFUs
Instruments and Detectors for the TMT
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IRIS — Detector Requirements
Baseline:
• TIS (Teledyne) H4RG
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4096x4096 detectors
15 µm pixels
= 0.8 to 2.5 µm coverage
32 channel read-out ASIC controller (on-board)
Goal: 2 cents/pix (current is ~9 cents/pix for H2RG)
Status
— H4RG-15 development recently funded by the NSF
— JWST SIDECAR ASICs use 4 read-out channels
— testing cryo-ASICS at UCLA/Caltech (ESO, UMich, RIT, etc etc)
12 OCT 2009
Instruments and Detectors for the TMT
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IRIS — Detector Requirements
Baseline:
• TIS (Teledyne) H4RG
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4096x4096 detectors
15 µm pixels
= 0.8 to 2.5 µm coverage
32 channel read-out ASIC controller (on-board)
Goal: 2 cents/pix (current is ~9 cents/pix for H2RG)
Concerns:
— Saturation / Read rate: 1 sec read-out speeds needed for imaging
— Thermal stability scaling up area from 2k to 4k
— Further improving ASICs:
• Simplify handling, cabling, control software
• Continuing to minimize power, heat dissipation, mass, etc.
12 OCT 2009
Instruments and Detectors for the TMT
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“Early-light” TMT instruments — WFOS/MOBIE
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PI / optical designer: Rebecca Bernstein
Project Manager: Bruce Bigelow
Project Scientist: Chuck Steidel
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Science Team:
Chuck Steidel (Caltech)
Rebecca Bernstein (UCSC)
Jason Prochaska (UCSC)
Judy Cohen (Caltech)
Alice Shapley (UCLA)
Raja Guhathakurta (UCSC)
Connie Rockosi (UCSC)
Sandy Faber (UCSC)
Bob Abraham (U. Toronto)
Jarle Brinchmann (Leiden)
Jason Kalirai (STScI)
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — overview
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Conflicting priorities: Multiplexing (Discovery) or Resolution (Diagnostic) ?
— Resolution (λ/Δλ): 1,000 – 5,000
— Multiplexing:
100’s
— Science examples: IGM structure and composition at 2<z<6
stellar populations, chemistry, and energetics z>1.5
Wide Field Multi-Object spectrographs: DEIMOS (Keck), VMOS (VLT), IMACS (Magellan)
Different
objects
12 OCT 2009
within order
Instruments and Detectors for the TMT
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WFOS/MOBIE — overview
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Conflicting priorities: Multiplexing (Discovery) or Resolution (Diagnostic) ?
— Resolution (λ/Δλ): 8,000 – 20,000 (depending on object/slit size)
— Multiplexing:
10’s
— Science examples: Kinematics and abundances of stars w/in 20 Mpc,
Galactic and Local Group structures.
Echellette spectrographs: ESI (Keck), MagE (Magellan), XShooter (VLT)
Note:
background
dominated!
Different
orders
12 OCT 2009
within order
Instruments and Detectors for the TMT
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“Early-light” TMT instruments — WFOS/MOBIE
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So do both:
Multi–object Broadband Imaging Echellette :
single-order, low resolution / multi-order, moderate resolution
Object: 2”
Spacing =
2.5” x #orders
Sky: 2”
Working example – MOE (Multi-Object Echellette, prism+grating) in IMACS on Magellan
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — overview
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Observer’s choice:
— 1000< R < 8000 and 100’s – 10’s objects
— Always can get full wavelength coverage
• More orders  fewer objects
• More objects  Order-blocking filters (1–5 orders)
— 2-5” long slit  fixed by order-spacing (prisms)
— Long slit  1 order
Object: 2”
Spacing =
2.5” x #orders
Sky: 2”
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — overview
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High transmission 0.3-1.0 µm
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Slit-mask fed
ADC (fused silica)
Mirror collimator
Dichroic split at ~550nm
Prism cross-dispersion
Reflection gratings
Refracting cameras
• Blue: fused silica, CaF2
• Red: fused silica, glass, CaF2
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — overview
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High transmission 0.3-1.0 µm
Pixel scale: 256 µm/ arcsec (if 15µm pix: 18 pix/arcsec !)
Focal plane: 220mm x 160 mm (big but not huge)
Readout control:
— Single-order: Nod/shuffle for background subtraction
— Multiple-order: charge “shifting”
~160 mm
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — Detector Requirements
“Requirements”
Dark current:
Read noise:
Readout:
Quantum efficiency:
Pixel size:
Device pixel format:
Mosaic format:
Dynamic range:
Controllers:
Blue Channel
Red Channel
< 0.003 e-/sec (binned)
same
< 4 e- at TBD pix/sec (binned)
time: 4 sec (binned)
direction: parallel transfer along short axis (rectangular)
The higher the better! Red/Blue optimized
≥15 µm (will bin as necessary)
TBD (minimize gaps)
TBD (e.g.: 4x2 mosaic, 3K x 8K x 15 µm pixels)
TBD (need high full-well for “summing“ pixels)
ASICS? (Minimize heat, power, mass. Simplify handling, cabling, software)
~160 mm
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — Detector Requirements
“Requirements”
Dark current:
Read noise:
Readout:
Quantum efficiency:
Pixel size:
Device pixel format:
Mosaic format:
Dynamic range:
Controllers:
Blue Channel
Red Channel
< 0.003 e-/sec (binned)
same
< 4 e- at TBD pix/sec (binned)
time: 4 sec (binned)
direction: parallel transfer along short axis (rectangular)
The higher the better! Red/Blue optimized
≥15 µm (will bin as necessary)
TBD (minimize gaps)
TBD (e.g.: 4x2 mosaic, 3K x 8K x 15 µm pixels)
TBD (need high full-well for “summing“ pixels)
ASICS? (Minimize heat, power, mass. Simplify handling, cabling, software)
STA OTA-CCDs for WIYN/ODI
MIT-LL Blue CCDs on Keck/HIRES
Backside illuminated
12 OCT 2009
Instruments and Detectors for the TMT
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WFOS/MOBIE — Detector Requirements
“Requirements”
Dark current:
Read noise:
Readout:
Quantum efficiency:
Pixel size:
Device pixel format:
Mosaic format:
Dynamic range:
Controllers:
Blue Channel
Red Channel
< 0.003 e-/sec (binned)
same
< 4 e- at TBD pix/sec (binned)
time: 4 sec (binned)
direction: parallel transfer along short axis (rectangular)
The higher the better! Red/Blue optimized
≥15 µm (will bin as necessary)
TBD (minimize gaps)
TBD (e.g.: 4x2 mosaic, 3K x 8K x 15 µm pixels)
TBD (need high full-well for “summing“ pixels)
ASICS? (Minimize heat, power, mass. Simplify handling, cabling, software)
(CCD 231-68)
(CCD 281-84) 4K x 4K, 15 µm pix
EEV
3K x 8K, 15 µm pix
(STA 1600B) 10.5K x 10.5K, 9 µm pix
EEV
16 output channels
STA
12 OCT 2009
Instruments and Detectors for the TMT
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Summary — “Generic” detector requirements
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Pixel scales: 2.2 mm/arcsec (big)
— Larger pixels
• If binning, need large dynamic range in wells
— Larger area
• Mosaics (not large compared to imaging surveys
• Packaging / controllers should be robust, compact (on-board?)
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Backgrounds: high compared to sources
— High signal levels (imaging, optical or IR)
• Read noise irrelevant
• Read-out speed critical
— Low signal levels (spectroscopy)
• Read noise critical
• Read-out speed less relevant
— Sky subtraction critical
• Charge shuffling — very appealing, CTE must be high
• Parallel transfer orientation — short or long axis of rectangular CCD)
• Orthogonal charge transfer — potentially interesting
12 OCT 2009
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This slide intentionally left blank.
Motivation — why science scales with aperture
•
Sensitivity (time to get to a given signal to noise)
— Enables: fainter, higher resolution (spatial, spectral), more targets, more distant…
— How it scales with D (in the background dominated regime)
Nobject
S
t D2
t D2
t D2






2
2
N
n pix
2
N object  n pix (N bkgnd  RN )
n pix t D


Nsource  number of photons from source
1 D2
sensitivity   2
t 
f
  (t D2 )
h
= flux of the source

f
 = efficiency (at mosph to ccd)
 = bandpass widt h
t (D2 ) = exp. t ime,collecting area
n pix =  2 = number of pixels source illuminate
12 OCT 2009
Instruments and Detectors for the TMT
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Generic detector requirements
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Pixel scales: 2.2 mm/arcsec (big)
— Larger pixels
• If binning, need large dynamic range in wells
— Larger area
• Mosaics (not large compared to imaging surveys)
• Packaging / controllers should be robust, compact (on-board?)
•
Backgrounds: high compared to sources
— High signal levels (imaging, optical or IR)
• Read noise irrelevant
• Read-out speed critical
— Low signal levels (spectroscopy)
• Read noise critical
• Read-out speed less relevant
— Sky subtraction critical
• Charge shuffling — very appealing, CTE must be high
• Parallel transfer orientation — short or long axis of rectangular CCD
• Orthogonal charge transfer — potentially interesting
12 OCT 2009
Instruments and Detectors for the TMT
52
The TMT project — Performance challenges
•
Example of performance challenge: wind-disturbance rejection
— dynamic response analysis: critical (and new!)
TMT
180o
Wind speed contours with 100% vents open
(flow along x-axis, Uo ~ 5 m/s)
12 OCT 2009
Instruments and Detectors for the TMT
53
The TMT project — Performance challenges
•
Example of performance challenge: wind-disturbance rejection
— dynamic response analysis: critical (and new!)
Note: motion of image = 2x [angle of Secondary Mirror]
2nd fore-aft mode (8.94 Hz)
GMT
(Not to scale.)
12 OCT 2009
Instruments
and Detectors
for the Heger
TMT for GMT
Modeling by S. Gunnels
and Simpson,
Gumpertz,&
54
The TMT project — Performance challenges
•
Example of performance challenge: wind-disturbance rejection
— dynamic response analysis: critical (and new!)
Note: motion of image = 2x [angle of Secondary Mirror]
GMT
12 OCT 2009
Instruments
and Detectors
for the Heger
TMT for GMT
Modeling by S. Gunnels
and Simpson,
Gumpertz,&
55
NFIRAOS — overview
•
CILAS conceptual design studies & performance demonstrators:
—
—
12 OCT 2009
9x9 subscale DM in 2006
20 Hz Tip/tilt stage prototype demonstration now underway
Instruments and Detectors for the TMT
56
NFIRAOS — overview
•
CILAS conceptual design studies & performance demonstrators:
—
—
12 OCT 2009
9x9 subscale DM in 2006
20 Hz Tip/tilt stage prototype demonstrated (removes need for tip/tilt mirror)
Instruments and Detectors for the TMT
57
“Early-light” TMT instruments — WFOS/MOBIE
•
•
•
Low: R~1000
Medium: R~ 2,500 and/or 5000
High: R ~ 8,000
Only dispersion elements change.
Each grating is fixed.
TMT focal plane.
(mask not visible)
collimator
grating
Fold mirror (red side)
Dichroic (blue side)
12 OCT 2009
Instruments and Detectors for the TMT
58
“Early-light” TMT instruments — WFOS/MOBIE
•
•
•
Low: R~1000
Medium: R~ 2,500 and/or 5000
High: R ~ 8,000
Only dispersion elements change.
Each grating is fixed.
TMT focal plane.
(mask not visible)
collimator
grating
Fold mirror (red side)
Dichroic (blue side)
12 OCT 2009
Instruments and Detectors for the TMT
59
“Early-light” TMT instruments — WFOS/MOBIE
•
•
•
Low: R~1000
Medium: R~ 2,500 and/or 5000
High: R ~ 8,000
Only dispersion elements change.
Each grating is fixed.
TMT focal plane.
(mask not visible)
collimator
grating
Fold mirror (red side)
Dichroic (blue side)
12 OCT 2009
Instruments and Detectors for the TMT
60
“Early-light” TMT instruments
Instruments
Near-IR DL Spectrometer &
Imager (IRIS)
Spectral
Resolution
≤4000
Wide-field Optical
Spectrometer (WFOS)
300 - 5000
Multi-slit near-DL near-IR
Spectrometer (IRMS)
2000 - 5000
Mid-IR Echelle Spectrometer
& Imager (MIRES)
5000 - 100000
ExAO I
(PFI)
50 - 300
High Resolution Optical
Spectrograph (HROS)
30000 - 50000
MCAO imager
(WIRC)
5 - 100
Near-IR, DL Echelle
(NIRES)
12 OCT 2009
Science Case
• Assembly of galaxies at large redshift
• Black holes/AGN/Galactic Center
• Resolved stellar populations in crowded fields
• Astrometry
• IGM structure and composition 2<z<6
• High-quality spectra of z>1.5 galaxies suitable for measuring stellar pops,
chemistry, energetics through peak epoch of gal form.
• Near-IR spectroscopic diagnostics of the faintest objects
• Close cousin of MOSFIRE for Keck
• Physical structure and kinematics of protostellar envelopes
• Physical diagnostics of circumstellar/protoplanetary disks: where and
when planets form during the accretion phase
• Direct
detection and spectroscopic characterization of extra-solar planets
• Stellar abundance studies throughout the Local Group
• ISM abundances/kinematics, IGM characterization to z~6
• Extra-solar planets!
• Galactic center astrometry
• Stellar populations to 10Mpc
• Precision radial velocities of M-stars and detection of low-mass planets
5000 - 30000
• IGM characterizations
for z>5.5
Instruments
and Detectors for
the TMT
61
“Early-light” TMT instruments — WFOS/MOBIE
•
1 order:
— Faintest sources, survey mode
— Nod/shuffle (20-30 sec beam-switching): best (<0.1%) background subtraction, no “fitting”
•
Multiple-orders:
— F/# variability across image: difficult to nod/shuffle between slits
— Multiple/short exposures: low read noise, even with high binning.
~2”
A
A
~4”
~2”
12 OCT 2009
B
B
Instruments and Detectors for the TMT
62