Subaru Strategic E xploration of E xoplanets and Disks with - - PDF document

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Subaru Strategic E xploration of E xoplanets and Disks with HiCIAO/ AO188

( ( SE E DS=種 )

HiCIAO at Nasmyth AO188 2008.11.28 Tamura & Mayama

• n behalf of

the SE E DS team (list shown later)

Today’s Outlines

1.Introduction

• --How infrared observations(Subaru)

collaborate with radio

• bservations(ALMA)

2.Previous Star & Planet formation

researches by Subaru Telescope

3.SEEDS projects (instruments, sciences,

target summaries)

4.Summary (Subaru ALMA)

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ALMA strategy Infrared Radio

Infrared (Subaru)～0”.1 scattering light from star

and disk.

• detailed morphology(disk size,inclination, color,

etc.)

Radio (ALMA)～0”.01 (after 2011)

• disk mass, velocity distribution etc.
• Provide original targets to ALMA-Japan team.

Infrared observations: precursor to ALMA

• 1. Clouds collapse under gravity

10,000 yr IRSF/SIRIUS

• 2. Protoplanetary disks
• 3. Comets &

asteroids form

• 4. Planetary

system 1 Myr Subaru/CIAO 10 Myr Subaru/CIAO/POL 100 Myr Kaguya

E volution diagram

• from clouds to planets
• 0. Cloud and cloud cores

Currently best studied with NIR

Then ALMA from ~ 2011

3 Diversity of proto- Planetary disks Compact disk around massive YSOs

Subaru has an AO Coronagraph since 2001

CI AO + 36-actuator AO at Cass.

First dedicated cold coronagraph on 8-m telescopes

Young very low-mass Companion

Fukagawa+04,+06; Tamura+06; Kudo+07; Itoh+05; Jiang+06; +

Spiral-shape Disk around 2Mo-4Myr Herbig Ae star: AB Aur

disk with spiral arms (r= 450 AU) trailing arm ← com. w/radio data

+ brighter forward scattering

no nearby companions

Grady et al. (1999)

13CO Velocity field

Mannings (1997)

1000 AU 400 AU 100 AU (d= 144 pc) Fukagawa, Hayashi, Tamura et al. (2004)

1.6 μm n e a r

• s

i d e

brighter fainter flared disk

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Disk Really Spiral ? Disk Really Spiral ? -

• YE

S YE S

White White contours: contours: 345 GHz dust continuum (SMA) 345 GHz dust continuum (SMA) Lin Lin et al. 200 et al. 2006, ApJ 6, ApJ

A suggestion of planet formation by gravitational instability? (for some systems) Matsuo et al. 2007, ApJ

1 ≤ Σ Ω = G c Q

s

π

Probably supplies of matter from the envelope maintain the weak instability.

⇒ Q ~ 2; “weak” instability

Mdisk ~0.15M

Gravitational instability?

(instability condition)：

I n fact, planets imaged around A stars (HR8799, Fomalhaut) at r> 25AU !! Marois et al./ Kalas et al. 08

Disk directly imaged even around only 0.1 Solar-Mass T Tauri Star: FN Tau

Resolution: 0.14’’(H =21.5@5σ) r=260AU face-on disk detected!

• almost face-on
• lowest mass star whose disk has

been directly imaged.

Did not expect such a bright disk around low-mass stars. Surface brightness profile: ｒ - 2.5 → Flare-disk with efficient forward scattering.

FOV = 11” x 11” mask size = 0.8”

H-band (1.6μm) image

Kudo, Tamura et al. (2004)

5 Diversity of proto- Planetary disks Compact disk around massive YSOs

Subaru has an AO Coronagraph since 2001

CI AO + 36-actuator AO at Cass.

First dedicated cold coronagraph on 8-m telescopes

Young very low-mass Companion

But after 6 years' use, we could now improve;

• low order adaptive optics (AO36-> AO188+ Subaru),
• lack of differential capabilities (CIAO-> HiCIAO),
• limited upgrade flexibilities accepting various

coronagraph ideas and AO upgrades.

Fukagawa+04,+06; Tamura+06; Kudo+07; Itoh+05; Jiang+06; +

Nasmyth platfo rm Nasmyth platfo rm

T elesc o pe T elesc o pe

Co mmo n Co mmo n Optic s Optic s + +

AO AO Module Module Cor

• nagr

aph Cor

• nagr

aph Module Module IR Camer a IR Camer a Module Module High Contr ast High Contr ast Optic s Module Optic s Module

War m War m Co Cold ld

Cor

• nagr

aph Cor

• nagr

aph F

• c al masks

F

• c al masks

Pupil sto ps Pupil sto ps Differential Differential optic s

• ptic s

(Wo llasto n pr isms) (Wo llasto n pr isms) Hawaii 2 Hawaii 2-

• R

G R G 2 2k k × × 2 2k k array array

ASICS ASICS Sidec ar Sidec ar Contr

• ller

Contr

• ller

F ilter s F ilter s Co mmo n+Diffe re ntial Co mmo n+Diffe re ntial 188 188 ac tuator s ac tuator s AO AO F uture F uture : : Co mple me ntary Co mple me ntary ME M DM (32 ME M DM (32× ×32 32) )

HiCIAOConcept

Camera

Wollaston Prism

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The goals of the SEEDS survey

are to address the following key issues in exoplanet/ disk science:

① The detection and census of exoplanets

in the outer circumstellar regions around solar-mass stars.

② The evolution of protoplanetary and

debris disks.

③ The direct link between exoplanets and

circumstellar disks at a few AU to 10s AU regions for the first time.

What is the SE E DS project?: First Subaru Strategic Observations

Observations to be started in Early 2009.

• To conduct a Subaru-

HiCI AO-AO188 imaging survey in 5 years, searching for giant planets (~ 1-13 MJ) and protoplanetary/ debris disks around ~ 500 nearby solar-type young stars.

• Direct imaging is

indispensable for the detection of such "young", self-luminous planets, especially planets in outer circumstellar regions (~ a few AU-~ 20AU).

Proposed Observations in SE E DS

stars brown dwarfs planets

SEEDS age span SEEDS contrast

brighter and less-contrast when young

1M 10M 100M 1G 10Gyr

Note: Based on Burrow's model, but still fine with Marley's model.

Luminosity vs Age

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Disk Study---Our Goals

1.To reveal the morphology of the protoplanetary disks at 15-50 AU regions.

Disk structures that could be formed by planets or rather that lead to planet formation (gap, hole, warp, resonance)

2.To make a direct connection with giant planet formation where they can in fact form (not after migration) 3.To provide evidence for protoplanets as local low-polarized regions.

Main Targets of Disks ～Transitional Objects

Defined as the object with no or weak IR excess shortward of 10 μm and a significant excess at longer wavelengths

A possible signature of planets at least in the very inner region (<a few AU))

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SE E DS Target Summary: Original

SST/AKARI sample

TTS/HAeBE/ polarized sources

subcategory

U Ma/Hyades/ Pleiades/α Per

Tau/Sco Comment 5 Myr

• 6 Gyr

1-10 Myr 100 Myr

• 1 Gyr

~ 100 Myr 1-10 Myr Age < 130 pc ~ 140 pc < 30 pc 25-180 pc ~ 140 pc Distance 521 80 105 100 116 120 Number Debris disks

Protoplanetary

disks Nearby stars Open cluster SFR YSOs (e) (d) (c) (b) (a) Total number Disk Searches (in PDI mode) Planet searches (in methane SDI / ADI mode) Category

RA-DEC H-mag R-mag Sp-Type

We will conduct a 5-year legacy survey of ~ 500 solar-mass

young stars for direct imaging of exoplanets and disks in 120 nights with a "all-Japan" team collaborating with several distinctive foreign researchers (including Princeton, Taiwan, MPI , 2xUH, Goddard, Washington).

Our targets consist of 5 categories, each of which includes

about ~ 100 stars (enough for statistics).

We believe that we can image at least a handful of giant

(< 13 MJ) exoplanets in a few to 10s AU regions and the similar radial regions of many disks in each category.

Our planet/ disk survey is not only the most extensive one

so far but also about 3 years earlier than the other next generation surveys on 8-m class telescopes. Note GPI / SPHERE are both in the southern hemisphere.

Various follow-up programs should be organized, including

spectroscopy with various instruments and telescopes.

The observations will start from early 2009. Provide our original targets from SEEDS to ALMA team.

Propose to observe with gas and dust at once under an early science category.

SUMMARY