MATISSEMulti AperTure Mid-Infrared SpectroScopic Experiment

Sebastian WolfMATISSE Project Scientist

Emmy Noether Research Group “Evolution of Circumstellar Dust Disks to Planetary Systems”Max Planck Institute for Astronomy, Heidelberg

Bruno Lopez

PIObservatoire de la Cote d’Azur, Nice

+ Science Team

The Progenitor: MIDI

Perfect combination of observing wavelength (~10m) and spatial resolution (VLTI baselines => 10-20mas)

=> regions with hot dust can be spatially resolved

since 2002observations of the hot dust in circumstellar disks, AGB stars,

winds of hot stars, massive star forming regions, tori of AGNs, …

Results:Very successful in interferometric spectroscopy

(chemical composition of dust on different spatial scales)

Concept of mid-infrared long-baseline interferometry proven to work

but …

Mid-Infrared Interferometric Instrument

MIDI’s limitations

a) Small number of visibility points b) Lack of Phase Information

Investigation of small-scale structures (= main goal of MIDI) and quantitative analysis of spectroscopic observation

strongly limited

c) Interpretation of MIDI data:Comparison between modelled and observed visibility

points, using 2D models with point-symmetry (usually even rotation symmetry)

Approach justified only by large-scale (if at all existing) symmetries, but expected to be strongly misleading or

simply wrong on size scales investigated with MIDI

Proposed 2nd Generation VLTI Instrument

Specifications:

• L, M, N, Q band: ~2.7 – 25 m• Spectral resolutions: 30 / 100-300 / 500-1000• Simultaneous observations in 2 spectral bands

What’s new?

• Image reconstruction on size scales of 3 / 6 mas (L band) 10 / 20mas (N band) using ATs / UTs

• Multi-wavelength approach in the mid-infrared3 new mid-IR observing windows for interferometry (L,M,Q)

• Improved Spectroscopic Capabilities

MATISSE Multi AperTure Mid-Infrared SpectroScopic Experiment

High-Resolution Multi-Band Image Reconstruction+ Spectroscopy in the Mid-IR

MATISSE

MATISSE Multi AperTure Mid-Infrared SpectroScopic Experiment

AMBER

JWST

MATISSE Multi AperTure Mid-Infrared SpectroScopic Experiment

High-Resolution Multi-Band Image Reconstruction+ Spectroscopy in the Mid-IR

Successor of MIDI:Imaging Capability in the entire mid-IR accessible from the ground

Successor of AMBER:Extension down to 2.7m + General use of closure phases

Ground Precursor of DARWINWavelength range 6-18m

The M

ATIS

SE T

eam

The M

ATIS

SE T

eam

Individual Contributions

Obs. de Lyon, Obs. de Grenoble, Universite de Lille, TLS Tautenburg

Letters of Intent

Meudon, Torino-INAF

Studies:

a) Science Cases: Complex Structures

• Star and Planet Formation• Circumstellar Environment: Low / Intermediate mass stars

Massive StarsMultiple Stars

• Protostellar Disks: Planet FormationDisk evolution: Young

=> Debris Disks

• Extrasolar Planets

• AGBs / Evolved Stars / Hot Stars

• Active Galactic Nuclei

b) Image Reconstruction Studies

Science Team

The circumstellar environment of young low and intermediate mass stars

• Planet forming region

• Emission from hot dust from the inner region

Earth - 14 mas Jupiter - 74 masNeptune - 429

mas

d=140pc

AB Aurigae (Fukagawa, 2004)

Complex outer disk structures observed => Complex inner disk structure expected

FU Orionis outbursts -- Variability in general (flux, polarization)

-- Expected influence from the formation of Jets/Outflows

The circumstellar environment of young low and intermediate mass stars

Is there indirect or direct evidence for the presence of planets?Protoplanets:

Significant influence on the surface density / brightness profile: Hot spot / Gaps

Hot Accretion Region around the Planet

i=0deg i=60deg

10m surface brightness profile of a T Tauri disk

with an embedded planet ( inner 40AUx40AU,

distance: 140pc)

[Wolf & Klahr 2005]

The circumstellar environment of young low and intermediate mass stars

Is there indirect or direct evidence for the presence of planets?

Density profile of a 0.05 Msun disk with a Jupiter-mass planet orbiting a solar-mass star [Wolf, Gueth, Henning, Kley

2002]

m image of a) an undisturbed disk and b) a disk with a gap at 4AU

Location of the Planet formation region =>

Gaps are expected to occur in the mid-infrared bright region of disks

Massive Star FormationM*>10Msun

Butterfly Star (low mass young stellar object)

In a typical distance of nearby massive star forming

regions.

Massive Star FormationM*>10Msun

High-mass star forming regions are much more distant (in average)than those of low-mass stars (high-mass: 3-7kpc vs. low-mass: 0.1-0.3 kpc)

JHK composite of NGC 3603 from ISAAC data, dimension 25'' x 25''

OB starsOB stars- form preferentially in the centre of dense star - form preferentially in the centre of dense star clustersclusters- seem to live pref. in (tight) binary and higher order - seem to live pref. in (tight) binary and higher order systemssystems

The Orion BN/KL region at 12.5m,dimension 10'' x 10'' (distance 450

pc) [Shuping et al. 2004]

High number density of High number density of objectsobjects

Enhanced outflow activityEnhanced outflow activity

Strong stellar winds from Strong stellar winds from the massive stars after the massive stars after ignitionignition

Massive Star FormationM*>10Msun

What we can do with MIDI …

W3: UCHII region

Objects of this class are often faint in the near-IR, but bright in the mid-IR!

MATISSE

will for the first time allow a comprehensive

comparison between low and high mass star formation

Linz et al. 2004

[Disks, Jets, Multiplicity,…]

Image Reconstruction Studies

Goal:Justification that MATISSE will indeed be able to answer the questions addressed in the individual Science Case Studies

Strategy:Simulation of a realistic observation procedure

Image Reconstruction Studies

Problem: There are no observed 10m images of the targets on the size scale to be investigated

Solution: Radiative Transfer Simulations (MC3D)

10m image of a circumstellar disk with an inner hole, radius 4AU

(inclination: 60deg; distance 140pc, inner 60AU x 60AU)

Image Reconstruction Studies

SimVLTI3 :- Based on SimVLTI- Simulation of 3/4 beam combination

+ closure phases- Location of all AT stations added- Output: OI-FITS format

Definition of the Observing Procedure

+ location of ATs, number of nights, noise, etc, …

Image Reconstruction Studies

Tracks in the uv plane

Image Reconstruction Studies

Building Block Method (K.-H. Hofmann)

Hybrid Mapping & Self-Calibration (S. Kraus)

Difference Mapping(L. Mosoni)

Reconstruction with Building Block

Method

Image Reconstruction Studies

All 3 applied image reconstruction techniques allow to reconstruct main features in the considered

disk model

Best results: Building Block Method (Hofmann & Weigelt)

Sufficient uv coverage: 3-5 nights of observations

with ATs (at varying locations)

Improvement of reconstructed images:

4 telescopes (instead of 3)UT Single-dish data + VLTI (UTs/ATs)

interferometric data

Conclusions: Image Reconstruction Studies

Multiwavelength Imaging(L - M - N - Q)

Observations in different bands

• … trace regions with different characteristic temperatures

• …provide image with different spatial resolution

• … allow a comparison with lower-resolution images obtained at large telescopes with adaptive optics – tracing the large scale structure if the targets – in different wavelength regions (L/M: NACO, N/Q: VISIR)

L M N Q

Multiwavelength Imaging(L - M - N - Q)

Depending on the individual band

• …unique spectral features (dust/gas) are accessible

• …spectral features can be investigated that correspond to dust species which can also be observed in N band

L M N Q

L band

• H2O ice broad band feature (2.7-4.0m)

• PAHs: 3.3m, 3.4m

• Nanodiamonds: 3.52m

• Highest Sensitivity in the MIR (reduced background emission)

M band

• CO fundamental transition series (4.6-4.78m)

• CO ice features (4.6-4.7m)

• Recombination lines, (e.g., Pf at 4.65m)

Spectroscopy

The 3-25m spectral region is extremly rich in spectral diagnostics of gas and dust – covering a huge range of physical and chemical conditions

Gas

strong vibrational lines of abundant molecules (CO, OH, H2O, SiO, C2H2)

Dust

oxygen-rich dust

amorphous silicates, crystalline silicates (e.g. forsterite)

simple oxides (SiO2, amourphous Al2O3, Spinel – MgAl2O2)

other dust species

FeS (most abundant sulfur bearing solid), …

carbon-rich dust

TiC, PAHs, Nano-Diamonds

volatile dust or ice species

H2O ice (3.1 / 12m), CO (4.7m)

Example Application

Planet Formation - Protoplanetary Disks

Critical tests of models for the radial distribution of different dust species

Dust evolution in disks?

Determination of crystallization region / processes? - Radial Mixing Efficiency?

Origin of nano-diamonds in meteorites + IPD?

Distribution of Volatiles

Key importance for understanding the complex disk chemistry: Many (organic) molecules are formed in ice mantles – Transport to inner disk

region – Sublimation / Release to the gas phase

Spatial distribution of water / CO ice? - Where is the snowline?

Specifications:

• L, M, N, Q band: ~2.7 – 25 m• Spectral resolutions: 30 / 100-300 / 500-1000• Simultaneous observations in 2 spectral bands

• Image reconstruction on size scales of 3 / 6 mas (L band) 10 / 20mas (N band) using ATs / UTs

• Multi-wavelength approach in the mid-infrared3 new mid-IR observing windows for interferometry (L,M,Q)

• Improved Spectroscopic Capabilities

• Key Science Programs can be performed in 3-5 AT nights

• Perfect complement to high-resolution facilities in the near-IR and mm

Summary Multi AperTure Mid-Infrared SpectroScopic Experiment

High-Resolution Multi-Band Image Reconstruction+ Spectroscopy in the Mid-IR

Poster by B. Lopez et al.

extra slides

Active Galactic Nuclei

~1% of all Galaxies hosts an AGNDust Torus => Obscuration in the optical (=> Seyfert I/II)

Structure of the Torus?

Preparatory Studies: MIDI

What is the size of the torus? How does it depend on luminosity?What is the overall shape of the torus?

Emission of the Tori of Seyfert I/II galaxies compatible with the unified scheme?

MATISSE

In how far is the torus structure regulated by outflow phenomena (supersonic winds, jets)?

What fraction of the dust emission from the inner few parsecs of an AGN is emitted by the torus?

Is the torus just the inner, AGN heated part of the central molecular disk in the host galaxy?

Can we find direct evidence for the clumpiness of torii?

The circumstellar environment of young low and intermediate mass

multiple stars

• Degree of Multiplicity ~ 40% - 60% (depending on SpT)• Multiplicity observed in all stages of stellar evolution• Multiplicity plays explicit role in the evolution of the companions

MIDI measures the auto-correlation function only!

Case Study: Close young binary/multiple systems: 1. Do we find binary/multiple stars with individual / circumbinary disks?2. What is the spatial distribution of the circumstellar material within the system?3. How do Binary/Multiple Systems evolve during the formation process?

Binary evolution, low angular momentum

[Bate et al. 1997]

Dust and Winds from AGB / Evolved Stars

Low/Intermediate Mass Stars => Cool Late Type Stars=> Develop dense dusty stellar wind (10-8-10-4 Msun)

=> Loose up to 80% of their initial mass => Contribute significantly to the replenishment of the ISM

Mechanism (stellar pulsation + radiation pressure) poorly understood

• Red Super Giants: Bipolar Outflows? Asymmetric Envelopes?Asymptotic Giant Branch Stars: Clumpy Environment?R Coronae Borealis: Localization of the Dust Cloud Formation?Post-AGB, RV Tau: Geometry of the disk torus?Symbiotic Stars / Novae: Role of Binarity?Planetary Nebulae: Disk Geometry?

Hot Stars

• Stellar Winds from Hot Stars strongly affect the ISM by many aspectsbut: Nature of these Winds still poorly understood.

How can dust be formed in this hostile environment?• Goals:

1. Dust geometry in Carbon Wolf-Rayet Binaries2. Conditions of dust formation in B[e] stars3. Dust core of Eta Car

Deconvolved MIDI acquisition image at 8.7m [Chesneau et al. 2005]Two epochs of near-infrared images of WR 104,

tracing the rotation of the spiral nebula [Monnier at el. 1999]