MCAO Brief Overview of the MCAO Science Case Francois Rigaut, Jean-René Roy

MCAOMCAO

Brief Overview of the Brief Overview of the MCAO Science CaseMCAO Science Case

Francois Rigaut, Jean-René Roy

May 24-25, 2001 MCAO Preliminary Design Review

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MCAOMCAO

OutlineOutline

• High resolution implementation at Gemini• The MCAO Science Workshop• Strawman Instrumentation for MCAO• Excerpt from the MCAO science case:

– Numerical Simulation & analysis results – The IMF in the Milky Way– Stellar populations in nearby galaxies– Distant galaxies: Assembly, Clustering, chemical

evolution

• Work to come on Science Case for CDR


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MCAOMCAO

An articulate AO Plan...An articulate AO Plan...

Gemini North:Gemini North:• 1999: Hokupa’a 36 (85 upgrade?) on GN• 2002: The Altair GN facility AO system• 2003: Laser on Altair increases Sky Coverage

Gemini South:Gemini South:• 2002: Possibly Hokupa’a south 85 on GS• 2005: GSAO & LGS available• 2006: MCAO available

Strong Team. Build or reinforce competence in-house.


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MCAOMCAOScience with MCAO: Science with MCAO: The Santa Cruz WorkshopThe Santa Cruz Workshop

• Following MCAO CoDR + 06/00 GSC, a workshop was organized to “explore the scientific opportunities for MCAO, quantify its advantages over current and planned AO systems for a comprehensive set of science cases and derive the MCAO instrument requirements”

• Organisation, preparation of science discussions led by P. Roche (Milky way), B. Schommer/ T. Armandroff/T. Lauer (nearby galaxies) and S. Morris (distant galaxies).

• Coordination: F. Rigaut/J.-R. Roy

• Modeling work: I. Baldry (AAO), C. Kobulnicky (U.Wisconsin) and E. Steinbring (CfAO) + GIRMOS studies

• Workshop Oct. 23-25, 2000 at CfAO, UCSC

– About 45 scientists from Gemini community

– Animated and open discussions


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MCAOMCAO

The Science Case DocumentThe Science Case Document

• Build prior, during and after the MCAO workshop.• ~ 15 direct contributors + many others• Contents:

– MCAO in the Gemini instrumentation program– CAO and MCAO– I: The global mass distribution of stars -MW– II: Evolution of galaxies thru stellar pop studies– III: Evolution of distant field and cluster galaxies– Appendices

• Science case document reviewed and commented by A.Ghez, R.Davies, B.Miller, I.Jorgensen


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MCAOMCAO

MCAO simulations, studiesMCAO simulations, studies

• Design study for MCAO deployable IFUs: sensitivities and source structures– I. K. Baldry and K. Taylor

• K band imaging with MCAO– I. K. Baldry

• A virtual observatory simulator (on line access)– E. Steinbring

• MCAO distant galaxies science: source density and emission line fluxes– H. Kobulnicky, S. Morris, I. Baldry & E. Steinbring

• GIRMOS: Operational Concept Definition Document– G. Wright & R. Sharples

• GIRMOS development studies– R. Haynes, I. K. Baldry, K. Taylor, D. Lee, et al.


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MCAOMCAOMultiplexing advantage and Multiplexing advantage and surface density of targetssurface density of targets

Haynes et al. 20001Proplyds/microjets in Orion

0.1T-Tauri stars

2Orion stars M<0.1 Msun

Schweizer&Seitzer 199810SSCs (B<23) ngc725

Kneib et al. 199610Grav. arcs A2218

Lowenthal et al. 19973Lyman break gals (R<25)

Fernandez-Soto et al. 19965-6HDF Irr (z=0.5-1)

Broadhurst et al. 199210All galaxies (K<20)

ReferenceN/arcmin2Object class


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MCAOMCAOMCAO Strawman MCAO Strawman InstrumentationInstrumentation

Nyquist sampled IMAGERNyquist sampled IMAGER

Band J H K/D [mas] 32 42 57

Pixel [mas] 16 21 29FoV (4k2) 66’’ 87’’ 118’’

• 80” field, 4k80” field, 4k22 pix, 20 mas/pixel pix, 20 mas/pixel

• ~ 4 million information points• Trade off FoV vs sampling • One plate scale !• Undersampling problems (HST) ? 80”x80”

ISS 2’ Ø hole and AO fold All images credit HST


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MCAOMCAOMCAO Strawman MCAO Strawman InstrumentationInstrumentation

d-IFU / GIRMOS:d-IFU / GIRMOS: • 16-32 units covering the 2’ Ø

field• ~ 0.1” “pixels”, 3” field IFUs• 1-2.5 m, R~5000 ->> Abingdon IIFlamingo II:Flamingo II: • Multi-slit spectrograph• 2.8 arcmin at F/34 (vs 2 arcmin MCAO

FoV)• Slit width down to 0.1 arcsec


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MCAOMCAO

Actual Anisoplanatism dataActual Anisoplanatism data

23”

Typical in H band, airmass=1.7, r0~ 14cm:

Hokupa’a : 0.12” to 0.19”-> CAO : 0.042” to 0.153”


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MCAOMCAOStellar population: Stellar population: SimulationsSimulations

15”

Generated Stellar fields:

• GC LF

• H-K=0

• Completed down to K=30

• + HB w/ |H-K| <2

• 1/10 GC crowding

• Isoplanatic conditions as for airmass=1.5


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MCAOMCAO

Seeing 0.65”, field 15”. 3600s. Crowded field.

AO


MCAO

Stellar populations: Stellar populations: SimulationsSimulations


Seeing


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MCAOMCAO

Cut-off on W43 (rich young cluster in the galactic plane). Blum et al 1999. CTIO 0.5-0.8” over 1’2

Data reduction: B.Blum, CTIO


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MCAOMCAO

The Quest for AstrometryThe Quest for Astrometry

• 1 mas/year = 4.5 km/s at 1kpc

• Typical V in Globulars, Open clusters = a few km/s

• Cluster partnership, mass distribution, ….• No Competition with space mission for sheer

accuracy (a few microarcsec), but (a) large field and (b) faint objects (8-m!)

• Problem = Systematics. Plate scale ~, static and dynamic distortions, detector, residual turbulence, non linearities in DM control.

• Auto-referenced method ?• Calibration scheme ? Precision and limitations?


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MCAOMCAO

The Science Case DocumentThe Science Case Document

• I : The global mass distribution of stars -MW– Probe the bottom of the H-burning sequence and sub-stellar

distribution as a function of environment

• II: Evolution of galaxies thru stellar pop studies– Calibration of the Sne Ia Zeropoint– Stellar pop in nearby Starbursts– Evolution of dIrr vs dE– Intergalactic stars– AGB & RGB tip in Virgo/Fornax clusters– Extragalactic Globular Clusters

• III: Evolution of distant field and cluster galaxies– Internal galaxies characteristics: Kinematics /

metallicity/extinction/SFR. Field and Clusters.– Lensed galaxies, galaxy clusters

Star formation and the Star formation and the Initial Mass Function in the Initial Mass Function in the Milky WayMilky Way

• Low end of the IMF: evolution w/ environment as a tool to investigate star formation processes– determine IMF for a variety of conditions:

densities, metallicities, ages

• Orion and other star forming regions: Densities

• Open Clusters: Ages• Globular Clusters: Metallicities• Young Stellar Super-Clusters: Densities, low to

high mass ratio

P. Roche, M. Meyer, H. Richer, P. McGregor, B. Brandl, P. Puxley, D. Simons, D. Crabtree and J.-R. Roy


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MCAOMCAOIMF as a function of cosmical IMF as a function of cosmical time and environmenttime and environment

• Orion - imaging– M, L distribution of stars at

bottom of H-burning sequence– Explore fragmentation limit

• In Orion, 1 mJ in 1hr at H• Orion - spectroscopy

– Surface gravity (M/R) and Teff– Proper stellar atmosphere

analysis• Astrometry: 0.5 mas/yr per

km/s– Membership and masses from

binaries


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MCAOMCAOYoung super stellar clusters: Young super stellar clusters: 30 Dor, NGC 3603, ...30 Dor, NGC 3603, ...

IMF: Probe high mass down to brown dwarfs

• 0.4 Msun, 1 Myr K=21.5– Beat confusion: PSF of

MCAO

• Spectroscopy – Age, mass– IFU privileged sampling

aperture


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MCAOMCAO

Instrument requirementsInstrument requirementsStar Cluster StudiesStar Cluster Studies

• Imaging – Largest field as possible (~80 arcsec)

• Edges more difficult for astrometry– Special readout time to avoid saturation of brightest

stars – Spatial resolution

• Nyquist sampled at H• Better understanding of crowding

– Faint stars vs background and foreground objects• Trade-off between sampling and field

• Spectroscopy (FLAMINGOS 2 is fine)– Slitlets for Orion: ~200 objects over 5x5 arcmin2– Dl = 0.1 mm per pointing; R = 4000 prefered


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MCAOMCAO

Nearby GalaxiesNearby Galaxies

• Contributors: B.Schommer, B.Brandl, G. da Costa,

T.Davidge, R.Doyon, T.von Hippel, J.R.Roy, ...

• General goal: investigates star formation in a variety of environment:– Starburst galaxies

– dIrr vs d Ellipticals

– Nearby galaxy spheroids

– Extragalactic globular clusters


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MCAOMCAO

Distant GalaxiesDistant Galaxies

• Contributors: S.Morris, M.Edmunds, I.Jorgensen, C.Kobulnicki, D.Koo, D.Schade, R.Sharples, T.Storchi-Bergmann, H.Yee, ...

• Galaxy formation and evolution:– Mass assembly of galaxies– When did the bulk of star formation occurred ?– History of galaxy clustering

• Proposed programs:– Evolution of field galaxies:

• Imaging: Morphology• Chemical evolution: metallicity/luminosity/linewidth

– Galaxy formation: Mass of galaxies at z=2– Galaxy formation in cluster– Gravitational lensing


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MCAOMCAOEmission lines in high z Emission lines in high z galaxiesgalaxies

The aim of MCAO spectro

-measure key diagnostic nebular lines to derive o velocities o extinction (Balmer dec) o abundances o SFR

-explore ~/> 10 objects per MCAO fields

-sample each object IFU > 10 points for gradients > 40 points for “breaks”


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MCAOMCAOGravitational lensing studies of Gravitational lensing studies of high z galaxieshigh z galaxies (Edmunds & Sharples)(Edmunds & Sharples)

• Exploit amplification– Spatial abundances

distribution– Resolved kinematics to study

gas flows and masses• Constrain inportance of

early strong flows and outflows

• Why?– Natural scale for strong

lensing (~0.25 Mpc) well-matched to MCAO fov

• Majority of lensed bkg galaxies lie at z = 1 – 2

• “gradient “ in z from center outward


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MCAOMCAOFormation of bulges/disks at Formation of bulges/disks at z=0.6 – 1.4 z=0.6 – 1.4 (H.Yee)(H.Yee)

• Understanding cluster growth/richness distribution of galaxy types– Variation of galaxy masses

• As as function of z• As function of radial distance

within cluster• Compare mean bulges and

disks to field• Strategy

– Imaging 10 clusters with MCAO and HST/ACS

– Non AO imaging with GMOS and FLAMINGOS

– MCAO spectroscopy at Ha to get rotation curves


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MCAOMCAO

The masses of galaxies at z=2The masses of galaxies at z=2 S. Morris et al.S. Morris et al.

• Understanding assembly of building blocks of galaxies at z = 1.3 – 2.7– Rotation curves from emission

lines; R ~ 3000-5000– MCAO multiplexing (12)

• Strong drive for 2’ field• But 1.5-2.0” IFU suffice

– Serendipity spectro of Ly galaxies (1 per sq. arcmin at z=4.5)


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MCAOMCAO……masses of galaxies: z=0.5-masses of galaxies: z=0.5-22

• Needed spectra = IFUs (~16)– Measurements of H disk rotation (50 km/s) to 1 scale

length (6 kpc: 0.’’75 at z=1)– [OII]+[OIII]/H or [NII]/[OIII] 12+log O/H

• Statistical sample requires multiplex gain– Surface density ~10 arcmin-2– 3 bins of morphology, luminosity, environment and redshift

• 10 objects per bin; >800 galaxies 30 nights

MCAOMCAO

MCAO Science CaseMCAO Science CaseThe next stepsThe next steps


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MCAOMCAO

From Jupiters to giant clustersFrom Jupiters to giant clusters


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MCAOMCAOImaging and spectroscopy with Imaging and spectroscopy with MCAOMCAO

• Imaging science cases: most convincing – Proof of astrometry to 2 mas/yr will greatly

strenghten the science case of MCAO imaging over ~1 arcmin field

• Spectroscopy with MCAO– Multi-slitlets: FLAMINGOS-2 fed by MCAO

could fulfill many key science objectives– Multi-deployable IFUs: most desirable for

distant galaxies and SSCs in nearby galaxies• Photon starved spectra


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MCAOMCAO

Exploring very distant galaxies (z>3)

Our knowledge of high z galaxies is rest frame UV based.

Probing the rest frame optical window is crucial:- Balmer Luminosities: SFR, extinction

o compare SFR(Ha) vs SFR(UV)- 12 + log O/H abundances- Integrated widths of lines= velocity dispersion Mass

Prominent HII region lines shifted to Near-IR, but need right match of z


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MCAOMCAO

LBG NIR spectraLBG NIR spectra

• Typically 2-hr exp. Times on Keck/NIRSEC or VLT/ISAAC

• R ~ 1500• Spectra dominated by

strong nebular lines– Little continuum

• Out of 15 galaxies, only 4 objects with sufficient S/N

Keck/NIRSPEC


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MCAOMCAO

Spatially resolved emission Spatially resolved emission

ISAAC spectrum:

[OIII] 5007, 18000s

FWHM = 0.62 arcsec (4.7

kpc)


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MCAOMCAO

MCAO view of z=3 galaxies will be no better than HST !

1’’ slit


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MCAOMCAO

Multiplexing requirementsMultiplexing requirements

• To extablish a radial behavior + a central value– Monotonic gradient: 12 points with S/N > 5– Gradient with single break (rotation curve or

abundance gradient in a young barred galaxies) : ~ 48 points with S/N > 5

– Gradient with two breaks : ~ 160 points with S/N > 5

• Recent spectroscopy of galaxies at z ~ 3 from Keck/VLT (e.g. Pettini et al. 2001) shows that it is extremely challenging – However, similar studies at z=1 are feasible


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MCAOMCAOSpectroscopy of distant galaxies Spectroscopy of distant galaxies (z>3)(z>3)

• Recording all the lines in JHK with adequate R and S/N one full night on 8-10 m

• Even with IR MOS, assembling a sizeable sample of high z galaxies major observational effort.– Getting robust physical parameters (O/H, rotation

curves) will require 30-50m


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MCAOMCAO……A living document: A living document: “final” version for CDR “final” version for CDR

• Develop simulation to strenghten the case for astrometry at the mas/yr level– Brent and Francois to explore further– Consult astrometrists

• MCAO spectroscopy – FLAMINGOS-2 capability at fulfilling near term

goals: Michael Meyer (Steward), Brian Miller (Gemini)


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MCAOMCAOSteps toward the final Steps toward the final version of the MCAO Science version of the MCAO Science CaseCase

• Establish for several science cases real fields– Put together potential MCAO fields, observing

schedule/timing (satellite interference), availability of tip/tilt stars

– Predict full field (JHK) performances and generate images/spectra

• Deadlines for “final” MCAO science case– GSC meeting of July 2001 and Board meeting

of November 2001 (updated from PDR input)– CDR in late 2002


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MCAOMCAO

ConclusionsConclusions

• Santa Cruz Workshop triggered strong interest for MCAO across the Gemini partnership– Provided backbone to current science case– Defined several MCAO imaging cases– FLAMINGOS-2 will cover most (but not all) spectroscopy

programs • GIRMOS to be re-visited during Abingdon II

• Community endorsement of MCAO+Near IR imager • Some of the science cases require a 30-50m

telescope with MCAO• Feasibility and more quantitive work to be

completed for CDR


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MCAOMCAO

PDR AgendaPDR Agenda

Thursday, 5/240800 Welcome 0805 Project overview 0830 Science case0930 Break0945 System overview1015 System modeling1100 AO Module optics1145 Lunch

1245 AO Module mechanics1340 AO Module electronics1400 Break1415 Beam Transfer Optics1510 Laser Launch

Telescope1545 Closed committee

session1800 Adjourn

Documents

MCAO Brief Overview of the MCAO Science Case Francois Rigaut, Jean-René Roy