planets & brown dwarf...

1

Gaël Chauvin, David Mouillet & Jean-Luc Beuzit

(LAOG Grenoble Observatory)

High contrast and High Angular Resolution Imaging

Planets & Brown Dwarf Companions

Spirit of Lyot Conference, Berkeley, June 2007

Gaël Chauvin

LAOG-CNRS, Grenoble Observatory, France

Outline

I- Brief introductionFirst discoveries (Gl299B, 51 Peg b).Development of new observing techniques.Advantage of direct imaging to explore the 5-500 AU missing link.

II- Observing challenge & technical needsFaint companion close to bright stars. Observing Limitations.Technical needs: AO, Coronography, Differential Imaging...

III- Target selection & main surveysTargets identification and selection: distance and age.Young, nearby stars. Intermediate-old stars, Very, nearby stars and Exoplanet hostsSummary of the main surveys: observing technique, sample size and performances

IV- Observing strategy & main results1) Deep imaging, 2) Astrometry and 3) Photometry + SpectroscopyAccess to planetary masses. Physical and chemical properties. Origin of formationTypical detection limits and statistical analysis

VI- Conclusion & perspectives


2

Gl 229 Ad = 5.7 pcAge ~0.5 GyrMA = 0.5 MSun

Gl 229 BTeff = 900 KMB=25 MJup

Sep = 45 UA

1995 : First brown dwarf, companion to Gliese 229 (Nakajima et al. 1995)‏Adaptive optics + coronography, Palomar Observatory

Brie

f Int

rodu

ctio

nFirst Brown Dwarf Discovery

Brown Dwarf: “predicted to be not massive enough to start Hydrogen-burning” (Kumar 1962) ‏

Mass < 75 MJup

Brie

f Int

rodu

ctio

n

Detection of the companion Epsilon Indi B (brown dwarf binary Ba & Bb)

Epsilon Indi A & Bab d = 3.6 pcAge = 0.8 - 2 GyrMBa = 50 MJup

MBb = 40 MJup

Sep = 1460 UA

1996-1997: Beginning of large surveys in optical (SDSS) and nIR (2MASS, DENIS) Hundreds of isolated brown dwarfs in the field (+600) ~10 Brown dwarf companions detected at large separations > 1000 AU

(Scholz et al. 2003)‏

Important Population of Brown Dwarfs

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

3

1997-2002 : New spectral classification beyond late-M dwarfs

- L Dwarfs (1300-2200K): atmosphere saturated with dust, extremely red colors. (optical) absence of TiO and VO - absorption of H2O

- T Dwarfs (500-1300K): dust condensation or rain-out in the atmosphere, bluer, near-IR spectra: absorption of H2O and CH4

L D w a r f s

T D w a r f s

M D w a r f s

E G P s M < 1 3 M J u p

B D s 1 3 < M < 7 5 M J u p

S t a r s M > 7 5 M J u p

New Spectral Classification

(Burrows et al. 2001) ‏

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

Discovery of the First Exo-planet

•1995 : Radial velocity measurements, 1st Exo-planet orbiting 51 Peg (Mayor & Queloz 1995) ‏

Minimum mass of M2sini > 0.45 MJup and a period P = 4.23 days

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

4

Nowadays,

•- The most successful technique!•- More than 200 Exo-planets discovered (www.exoplanets.org) •- Brown dwarf desert at short separations < 4 AU•- High diversity of masses, orbital parameters (P, a, e, M2sini) ‏

•Period – Mass – Eccentricity Distributions- RV precision allows access to telluric masses

- Host Stars Studies: Impact of MetallicityMultiplicityAge

Large Diversity of Planetary Systems

•1995 : Radial velocity measurements, 1st Exo-planet orbiting 51 Peg (Mayor & Queloz 1995) ‏

> G . M a r c y ' s R e v i e w

> X . B o n fi l s ' s T a l k

> M . M u g r a u e r ' s T a l k a n d T . S c h m i d t ' s P o s t e r

> X . B o n fi l s ' s T a l k

Minimum mass of M2sini > 0.45 MJup and a period P = 4.23 days

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

Ind

ire

ct

dir

ec

t

+ Astrometric Wobbling (VLTI/PRIMA, GAIA), Interferometry (SIM, TPF/Darwin) ‏

> Spectroscopic Characterization of Planet and BD atmopsheres

Radial Velocity

Pulsar Timing

Gravitational Micro-lensing

Photometric Transit(Secondary Eclipse)

Classical, HC & HAR Imaging

m2 sini (hyp. m1) ‏P, e, a, ω, T0

m2 sini (hyp. m1) ‏P, e, a, ω, T0

m2, m1, d ‏P, a (single event) ‏

R2, R1, m1 (e=0; R*-M*) ‏P, a, i, T0

m1, m2P, a, e, i, ω, T0

Planets (& BDs) hunting techniques

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

5

RV, Transit,Micro-lensing (< 5 AU)‏

> 200 exo-planetsBrown dwarf desert

Large surveys(> 500 AU) ‏

~10 brown dwarf companions2MASS and DENIS

Missing Link between 5 and 500 AU

- S o l a r S y s t e m

- C i r c u m s t e l l a r D i s k s

- M u l t i p l i c i t y

0 50 100 1000 (AU)1000‏

........... O o r t C l o u dK u i p e r

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

High Contrast/High Angular Resolution Direct Imaging

(Lowrance et al. 1999)‏TWA5 B (HST/NICMOS) ‏

R a p i d c o n fi r m a t i o n ( 1 - 2 y r s )

S p e c t r a l c h a r a c t e r i z a t i o n

S t u d y o f o r b i t a l p a r a m e t e r s

P h y s i c o - c h e m i s t r y ( S t r u c t u r e & a t m o s p h e r e ) ‏

O r i g i n o f f o r m a t i o n

Missing Link between 5 and 500 AU

- S o l a r S y s t e m

- C i r c u m s t e l l a r D i s k s

- M u l t i p l i c i t y

0 50 100 1000 (AU)1000‏

........... O o r t C l o u dK u i p e r

Brie

f Int

rodu

ctio

nB

rief I

ntro

duct

ion

6

Outline







Observing Challenge

D e t e c t / c h a r a c t e r i z e s o m e t h i n g f a i n t , s p a t i a l l y c l o s e t o s o m e t h i n g b r i g h t

- Relative flux (photometry)

Emitted light of the companionLuminosity vs model predictions(Mass, luminosity, Teff...)

- Relative position (astrometry)‏

proper motion (comoving?) ‏orbital motion (Bound companion?)‏

- Spectral information (spectroscopy)

Atmosphere characterizationMolecules, Dust propertiesGravity, Effective Temperature

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds

7

Technical Needs

- High image quality

High angular resolution PSF Stability

Calibration of statical aberrations

- PSF Halo Brightness

Halo attenuation? Inner working angle? Speckle-noise Photon-noise

- Intrinsic companion faintness

Long overall observationsBackground/Readout-noise limits

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds

C . M a r o i s , R . S o u m m e r ' s T a l k s

D e t e c t / c h a r a c t e r i z e s o m e t h i n g f a i n t , s p a t i a l l y c l o s e t o s o m e t h i n g b r i g h t

ESO3.6m/Come-On+ 1994

(Neuhäuser et al 05) (Janson et al. 2007) ‏

Technical Needs

I m p r e s s i v e E v o l u t i o n

G Q l u p

VLT/NACO 2005

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds

•L a r g e t e l e s c o p e s , w i t h A O s y s t e m f r o m t h e g r o u n d ( > L i s a P o y n e e r ) ‏

•Handling instrumental artefacts: design, active correction, calibration

8

Technical Needs

•L a r g e t e l e s c o p e s , w i t h A O s y s t e m f r o m t h e g r o u n d


•Coronography

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds

- Occulting Mask Saturated Imaging

- Lyot Coronography

Technical Needs

D e t e c t i o n L i m i t s :D e t e c t i o n L i m i t s :

H - b a n dH - b a n d

O b s . T i m e ~ 1 0 m i nO b s . T i m e ~ 1 0 m i n

S t a r , H = 5 - 6S t a r , H = 5 - 6

( d = 5 0 p c )( d = 5 0 p c ) ‏‏

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds



•Coronography

9

Technical Needs



•Coronography

•Differential techniques: ADI, SDI, Polarimetry

H S T r o l l a n g l e H S T r o l l a n g l e ( L o w r a n c e e t a l . 9 9 ; 0 0 ; 0 5 )( L o w r a n c e e t a l . 9 9 ; 0 0 ; 0 5 ) ‏‏

B e i n g r e v i s i t e d / o p t i m i z e d , f o r o b s .B e i n g r e v i s i t e d / o p t i m i z e d , f o r o b s .

p r o c e d u r e s a n d d a t a a n a l y s i sp r o c e d u r e s a n d d a t a a n a l y s i s

( M a r o i s e t a l . 2 0 0 6 ) ( M a r o i s e t a l . 2 0 0 6 ) ‏‏

D e t a i l s d e p e n d e n t o n t e l e s c o p e ,D e t a i l s d e p e n d e n t o n t e l e s c o p e ,

F o c u s , d e f e c t s o r i g i n a n d s t r u c t u r eF o c u s , d e f e c t s o r i g i n a n d s t r u c t u r e ……

> C . M a r o i s ' s T a l k

> J . F a r i h i a n d D . L a f r e n i è r e T a l k s

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds

Technical Needs

M e t h a n e - r i c h c o m p a n i o n , T 2 - T 8 B D s M e t h a n e - r i c h c o m p a n i o n , T 2 - T 8 B D s

S D I C o n c e p t :S D I C o n c e p t :

C F H T / T R I D E N T C F H T / T R I D E N T

( R a c i n e e t a l . 1 9 9 9 ; M a r o i s e t a l . 2 0 0 0 )( R a c i n e e t a l . 1 9 9 9 ; M a r o i s e t a l . 2 0 0 0 ) ‏‏

R e s u l t s :R e s u l t s : ( M c C a u g h r e a n e t a l . 1 9 9 4 ; ( M c C a u g h r e a n e t a l . 1 9 9 4 ;

C l o s e e t a l . 2 0 0 5 ; B i l l e r e t a l . 2 0 0 6 )C l o s e e t a l . 2 0 0 5 ; B i l l e r e t a l . 2 0 0 6 ) ‏‏

> B . B i l l e r ' s T a l k

> G . M o n t a g n i e r ' s T a l k

Obs

ervi

ng C

halle

nge

and

Tech

nica

l Nee

ds



•Coronography

•Differential techniques: ADI, SDI, Polarimetry

10

Outline







Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys

D i s t a n c e < 1 0 0 – 2 0 0 p c ‏

Target Selection: Stars near the Sun

11

E G P s M < 1 3 M J u p

B D s 1 3 < M < 7 5 M J u p

S t a r s M > 7 5 M J u p

Target Selection: AgeTa

rget

Sel

ectio

n &

Mai

n H

AR

and

HC

imag

ing

Sur

veys

(Burrows et al. 2001) ‏

- 1983. TW Hya, an isolated T Tauri star (Rucinski & Krautter 1983) ‏

- 1997. Identification of 5 first members of the TWA Association (Kastner et al. 1997) ‏

- Now. 5 associations: TWA, β Pictoris, AB Dor,Tucana/Horologium & η Chameleontis

+ New stars from the SACY survey

> Total of 200 - 300 young, nearby (AFGKM) stars ‏

Identification Groups: Zuckerman, Song et al.; Torres, de la Reza et al. Mamajek et al.; Ortega et al.; ByN et al.

Age & membership diagonostic- Abnormal colors, luminosity Optical/nIR photometry- Rotation & Stellar Activity Optical Spectroscopy: SpT, Hα, Li- Li Abundance X-ray Activity- Stellar Kinematics RV and proper motions

A g e ( < 1 0 0 M y r )

D i s t a n c e ( < 1 0 0 p c ) ‏

1) Young, nearby Associations

Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys

12

- HST/NICMOS Corono 45 Lowrance et al. (1999, 2000, 2005) ‏- Keck/NIRC AO-Corono - MacIntosh et al. (01); Kaisler et al. (01) - ESO3.6m/ADONIS AO-Corono 29 Chauvin et al. (2002, 2003) ‏- NTT3.5m/Sharp Saturated 32 Neuhäuser et al. (2003, 2005) ‏- VLT/NACO AO-Saturated 28 Masciadri et al. (2005)- VLT/NACO AO-Lp 22 Kasper et al. (2007)‏- VLT & MMT AO-SDI 45 Biller et al. (2007), Close et al. (2005) ‏

> Beth Biller's Talk

G S C 8 0 5 7 B

( C h a u v i n e t a l 2 0 0 3 )

T W A 5 B

( L o w r a n c e e t a l 1 9 9 9 )

H R 7 3 2 9 B

( L o w r a n c e e t a l 2 0 0 0 )

A B P i c B

( C h a u v i n e t a l 2 0 0 5 )


A g e ( < 1 0 0 M y r )

D i s t a n c e ( < 1 0 0 p c ) ‏

T y p i c a l d e t e c t i o n l i m i t s : MB

> 1 Mj u p

a t p h y s i c a l s e p a r a t i o n s > 1 0 - 4 0 A U

T o s e a r c h f o r a n d t o c h a r a c t e r i z e p l a n e t a r y m a s s c o m p a n i o n s

Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys

- HST/NICMOS Corono 45 Lowrance et al. (1999, 2000, 2005) ‏- Keck/NIRC AO-Corono - MacIntosh et al. (01); Kaisler et al. (01) - ESO3.6m/ADONIS AO-Corono 29 Chauvin et al. (2002, 2003) ‏- NTT3.5m/Sharp Saturated 32 Neuhäuser et al. (2003, 2005) ‏- VLT/NACO AO-Saturated 28 Masciadri et al. (2005)- VLT/NACO AO-Lp 22 Kasper et al. (2007)‏- VLT & MMT AO-SDI 45 Biller et al. (2007), Close et al. (2005) ‏

> Beth Biller's Talkand more results to come- HST/NICMOS Corono 109 > Jay Farihi's Talk- Gemini/GPDS AO-ADI 85 > David Lafreniere's Talk- VLT/NACO AO-Corono - Melo et al.; Chauvin et al.- Gemini/NICI AO-Corono - Liu et al.


Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys A g e ( < 1 0 0 M y r )

D i s t a n c e ( < 1 0 0 p c ) ‏


> 1 Mj u p

a t p h y s i c a l s e p a r a t i o n s > 1 0 - 4 0 A U

T o s e a r c h f o r a n d t o c h a r a c t e r i z e p l a n e t a r y m a s s c o m p a n i o n s

13

- Gemini/Hokupa'a Classical 31 Potter et al. (2002) ‏- Keck/NIRC AO-Corono 102 McCarthy & Zuckerman (2004) ‏ Lick/GEMINI AO-Corono 178- Palomar PALAO AO-Corono 101 Metchev et al. (2005, 2006)‏ KeckII/NIRC2- Spitzer Classical-midIR 73 Luhman et al. (2006)‏

H D 4 9 7 9 7 B

( M e t c h e v e t a l 2 0 0 4 )

H D 1 3 0 9 4 8 B C

( P o t t e r e t a l 2 0 0 2 )

H D 2 0 3 0 3 0 B

( M e t c h e v e t a l 2 0 0 6 )

2) Intermediate-old Stars

H N P e g B

( L u h m a n e t a l 2 0 0 6 ) Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys A g e ( 0 . 1 - 1 . 0 G y r )

D i s t a n c e ( < 2 0 - 5 0 p c ) ‏


> 1 0 Mj u p

( > 1 0 - 2 0 A U ) ‏

B D c o m p a n i o n s t u d y : E x t e n s i o n o f t h e B D d e s e r t a t i n t e r m e d i a t e s e p a r a t i o n s ?

- Palomar/AOC AO-Corono 24 (<10 pc) Nakajima et al. (1994) ‏- HST/WFPC Classical 13 (<13 pc) Schroeder et al. (2000) ‏- Palomar (60i, 200i) AO-Corono 107 (<8 pc) Oppenheimer et al. (2001)‏- Palomar PALAO AO-Corono 80 (<22 pc) Carson et al. (2005, 2006) ‏ - Palomar PALAO AO-Corono EPIcS sample > A. Tanner's Talk

3) Very Nearby Stars

H R 7 6 7 2 B

( L i u e t a l 2 0 0 2 )

G l 2 2 9 B

( N a k a j i m a e t a l 1 9 9 5 )

Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys A g e ( 0 . 1 - 1 0 . 0 G y r )

D i s t a n c e ( < 1 0 - 3 0 p c ) ‏


> 2 0 Mj u p

( 1 G y r ) a n d MB

> 6 0 Mj u p

( 1 0 G y r ) a t ( > 1 - 1 0 A U ) ‏


> V o l u m e - l i m i t e d s a m p l e o f A F G K M s t a r s

14

- Gemini/Hokupa'a AO-Classical 39 Close et al. (2002, 2003) - VLT/Gemini/Subaru AO-Classical 36 (<30 pc) Siegler et al., (2003, 2005) - CFHT/PUE'O AO-Classical (<12 pc) Beuzit et al. (2004) ‏- Gemini/Altair-NIRI AO-Saturated 41 (<20pc) Daemgen et al. (2007) ‏- VLT/NACO AO-Classical Biller et al. (2006); Montagnier et al. (2006) ‏ ‏

S C R 1 8 4 5 B

( B i l l e r e t a l 2 0 0 6 )

3) Very Nearby StarsTa

rget

Sel

ectio

n &

Mai

n H

AR

and

HC

imag

ing

Sur

veys A g e ( 0 . 1 - 1 0 . 0 G y r )

D i s t a n c e ( < 1 0 - 3 0 p c ) ‏


> 2 0 Mj u p


> 6 0 Mj u p

( 1 0 G y r ) a t ( > 1 - 1 0 A U ) ‏



> F o c u s e d o n M s t a r s

- Gemini/Hokupa'a AO-Classical 39 Close et al. (2002, 2003) - VLT/Gemini/Subaru AO-Classical 36 (<30 pc) Siegler et al., (2003, 2005) - CFHT/PUE'O AO-Classical (<12 pc) Beuzit et al. (2004) ‏- Gemini/Altair-NIRI AO-Saturated 41 (<20pc) Daemgen et al. (2007) ‏- VLT/NACO AO-Classical Biller et al. (2006); Montagnier et al. (2006) ‏ ‏

3) Very Nearby Stars

Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys A g e ( 0 . 1 - 1 0 . 0 G y r )

D i s t a n c e ( < 1 0 - 3 0 p c ) ‏


> 2 0 Mj u p


> 6 0 Mj u p

( 1 0 G y r ) a t ( > 5 - 1 0 A U ) ‏



> F o c u s e d o n M s t a r s

> L and T dwarfs multiplicity studies Bouy et al. (2003); Gizis et al. (2003) ‏Reid et al. (03): Burgasser et al. (2003) ‏

15

4) Stars with RV planets & RV driftsTa

rget

Sel

ectio

n &

Mai

n H

AR

and

HC

imag

ing

Sur

veys A g e ( 0 . 1 - 1 0 . 0 G y r )

D i s t a n c e ( < 5 0 p c ) ‏


> 2 0 Mj u p


> 6 0 Mj u p

( 1 0 G y r ) a t ( > 1 0 - 2 0

A U ) ‏

> Stars with RV planets

M a s s i v e c o m p a n i o n s a t l o n g - p e r i o d s ?

D y n a m i c a l i m p a c t o n i n n e r p l a n e t a r y s y s t e m s ?

- KeckII/kCam AO-Saturated 25 Luhman & Jayawardhana (2002) ‏- NTT/Sofi Classical-Saturated - Mugrauer et al. (2004, 2006, 2007) ‏- VLT/NACO AO-Corono 26 Chauvin et al. (2006, 2007)- VLT/NACO AO-Classical 103 Eggenberger et al. (2007) ‏- Spitzer Classical-midIR 48 Luhman et al. (2006) ‏

> Stars with long RV trends

- VLT/NACO AO-SDI > G . M o n t a g n i e r ' s T a l k

• Young Brown dwarfs

Favorable Contrast IR-AO, LGS-AO

> L. Close's Talk

• Star Forming Regions (1-120 Myr and >100 pc)

Chameleon, Pleiades, Taurussubstellar IMF StudiesVLM multiplicity

> A. Tanner's Talk

• White dwarfs

GD 165 B (Becklin & Zuckerman 1988) ‏Fossil of planetary system?

and more.....

D H T a u B

( I t o h e t a l 2 0 0 5 )

C H X R 7 3 B

( L u h m a n e t a l 2 0 0 6 )

G Q L u p B

( N e u h ä u s e r e t a l 2 0 0 5 )

2 M 1 2 0 7 B

( C h a u v i n e t a l 2 0 0 4 )

Targ

et S

elec

tion

& M

ain

HA

R a

nd H

C im

agin

g S

urve

ys

16

Outline







AB Pic

NACO/VLT, Ks + S27 (27 mas/pix), FoV 28'' × 28''Classical and coronographic (Ø = 0.7” et Ø = 1.4”) imagingObserving Time / source ~ 1 hr

I/3- Systematic Search for Faint Objects

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

17

Proper motion study of AB Pic b

AB Pic A:- Proper motion - Parallactic Motion

Follow-up at several epochs

2/3- Astrometric Follow-up Observations Background object or physical companion ?

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

AB Pic B2M0345 (L1)‏

H2OH2O

NaI 12CO 2-0

3-1

4-2

5-3

AB Pic BM ~ 10-20 Mjup et Sep = 260 AUSpectral Type ~L1

!! Gliese 86 B case !!same nIR L/colors for BD or WD

•Photometry versus predictions evolutionary modelsa •Identification of atomic and molecular lines: H20, CO, CH4, FeH, NaI, CaI, KI…•Confirmation of a cool atmosphere

3/3- Photometric & Spectroscopic Characterization

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

18

Results: Substellar companions of nearby stars

1 9 9 5 2 0 0 0 2 0 0 2 2 0 0 4 2 0 0 61 9 9 8

- G J 5 8 4 C

- G J 3 3 7 C D

- G l 5 7 0 D - ε I n d i B a b

- G l 4 1 7 B C- Gl1048 B

- GJ1001 BC

- Gl569 Bab

Gl229 B

TWA5 B HR7329 B

HD130948 BC

HR7672 B

GSC8048 B

HD49197 B Gl577 BC

DHTau B

HD203030 B

SCR1845 B

CHXR73 B

HD3651 B

HNPeg B

GQ Lup B

AB Pic B

G 1 9 6 - 3 B

AO, HST

Large Surveys, Classical Imaging

Spitzer

- GGTau B

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

2M1207 B

Results: Physical and Chemical Properties

Thermal Emission:

L (Teff & R) Mass, Age, composition (& Formation) ‏

Companions, thanks to the primary:

> known distance Hipparcos ParallaxMoving Cluster Method

> known metallicity Primary optical spectroscopy

> relatively well known age: age of the young, nearby associationPhotometry vs evol. modelsStellar kinematics, Dust lumikosityLi abundance, Stellar rotationStellar activity: X-ray, Hα, emission lines

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

19

nIR photometry L, Teff, R, M

Evolutionary Interior Models> Internal structure (Teff, L, mass, radius)Tucson: (Burrows et al. 1997; 1999)‏NASA-Ames: Marley et al. (2007) ‏Lyon: (Chabrier et al. 2000, Baraffe et al. 1998, 2003) ‏

Synthetic spectra of Atmospheric Models> Molecular, dust opacities. Dust formation/condensation> Boundary conditions on interior calculationsTucson: Burrow et al. (2001; 2002; 2006) ‏NASA-Ames: Marley et al. (1999; 2002) ‏Lyon: Allard et al. (2001; 2003) ‏‏‏

d , a g e

Results: Physical and Chemical PropertiesO

bser

ving

Stra

tegy

& M

ain

Res

ults


Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

nIR photometry L

nIR spectroscopy

d a g e

Teff, R, M

Spectral Type (Old field BDs)Spectral indexes (H2O, CO, CH4) ‏Bolometric corrections

Evol. Interior Models

Young / Old M, L dwarfs:

AB Pic B (10-20 Mjup; 260 AU)‏Spectral Type ~L1(Song et al. 2006) ‏

2MASS 0141; L0-L2(Kirkpatrick et al. 06)‏

20

R, M, L, age log(g), Teff


Synthetic spectra of substellar atmospheres> Molecular, dust opacities. Dust Formation/condensation> Boundary conditions on interior calculationsTucson: Burrow et al. (2001; 2002; 2006) ‏NASA-Ames: Marley et al. (1999; 2002) ‏Lyon: Allard et al. (2001; 2003) ‏‏

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

> K . L u h m a n ' s T a l k

d

nIR photometry L

nIR spectroscopy

d a g e

Teff, R, M

Spectral Type (Old field BDs)Spectral indexes (H2O, CO, CH4) ‏Bolometric corrections

Evol. Interior Models

M o d e l s : n e e d t o b e c a l i b r a t e d f o r y o u n g ( < 1 0 0 M y r ) a g e s a n d v e r y l o w m a s s e s

> D y n a m i c a l m a s s e s : E c l i p s i n g B i n a r y , D i s k K i n e m a t i c s , A s t r o m e t r y & S p e c t r o s c o p y

D M T a u , C Y T a u ( S i m o n e t a l . 2 0 0 0 ) ‏H D 9 8 8 0 0 A B ( B o d e n e t a l . 2 0 0 5 ) ‏T W A 5 A a b ( K o n o p a c k i e t a l . 2 0 0 7 )

2 M A S S 0 5 3 5 A B ( S t a s s u n e t a l . 2 0 0 6 )

A B D o r ( C l o s e e t a l . 0 5 , 0 7 ; L u h m a n e t a l . 2 0 0 6 ) ‏

‏


Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

> A . B o c c a l e t t i ' s T a l k

M . M a r l e y ' s T a l k : > U n c e r t a i n t i e s w i t h E v o l u t i o n a n d A t m o s p h e r i c M o d e l s

i n i t i a l C o n d i t i o n s

C o n v e c t i o n

F o r m a t i o n m e c h a n i s m s

C l o u d M o d e l l i n g

R e m a i n i n g l i n e s

C o m p o s i t i o n

21

M o d e l s : n e e d t o b e c a l i b r a t e d f o r y o u n g ( < 1 0 0 M y r ) a g e s a n d v e r y l o w m a s s e s

> D y n a m i c a l m a s s e s : E c l i p s i n g B i n a r y , D i s k K i n e m a t i c s , A s t r o m e t r y & S p e c t r o s c o p y

> H R - r e s o l u t i o n s p e c t r o s c o p y i n o p t i c a l + A t m o s p h e r i c M o d e l s

( M o h a n t y e t a l . 2 0 0 4 a , 2 0 0 4 b )

‏

Results: Physical and Chemical PropertiesO

bser

ving

Stra

tegy

& M

ain

Res

ults

M . M a r l e y ' s T a l k : > U n c e r t a i n t i e s w i t h E v o l u t i o n a n d A t m o s p h e r i c M o d e l s

i n i t i a l C o n d i t i o n s

C o n v e c t i o n

F o r m a t i o n m e c h a n i s m s

C l o u d M o d e l l i n g

R e m a i n i n g l i n e s

C o m p o s i t i o n

Large Surveys

Transits

Radial Velocity

µ Lensing

H C & H A R I m a g i n g

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

Results: Substellar companions of nearby stars

22

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts MB ~ 8 MJup

MA ~ 24 MJup

2M1207B, (Chauvin et al. 2005; Lodato et al. 2005) ‏

•> Opacity limit for fragmentation reached (Larson 1969) ‏

•> Overlap between formation mechanisms

•Other substellar companions (HC & HAR imaging):

•> Mass ratio, wide separation star/BD formation mechanism

•Soon, some ambiguous cases?

Formation scenario?

- Mdisk > 0.3 MA- Tcore Accr. > 10 Myr

Core-accretion (Pollack et al. 1996)‏ Disk Instability (Boss 1997) ‏ Collapse/Fragmentation (stars & BDs)‏

Results: 2M1207B, First Planetary Mass Companion?O

bser

ving

Stra

tegy

& M

ain

Res

ults

Y o u n g , N e a r b y S t a r

G K s t a r

K ~ 7

A g e ~ 1 0 M y r

d ~ 3 0 p c

E v o l . M o d e l

( B a r a f f e e t a l . 0 3 ) ‏

Results: Detection Limit Interpretation

23

Physical properties (mass, a, e) ‏of EGP and BD companion population

Monte Carlo Simulations

Detection Limits(minimum mass, projected physical separation)

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

tsResults: Statistical Analysis

Formation mechanisms of BDs & EGPs

Young (10-30 Myr), nearby stars: Population of EGPs at wide orbits?

- Probability Distributions: Semi-major axis P(a) ~ aα [0.3 – amax] AUEccentricity e = 0; RV distribution a

EGP Mass P(m) ~ m-1.5 [1 - 50] Mjup

- adjustement with RV surveys (3%, 1-3 AU, > 1 Mjup, Marcy et al. 2005) ‏

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts

> Observational constraints on the outer part of the planetray systems

Inp

ut

s

Results: Statistical Analysis

MC Drawing: Comparison with detection limits & null-detection

Probability for an EGP population to be consistent with the survey

Results: VLT/NACO-Lp (Kasper et al. 2007) ‏Small outer radii (amax < 15 AU) and Decreasing radial distrib. (α<0)

MMT-VLT/SDI (Biller et al. 2007) > Poster by E. NielsenRule out combination of M, e, constant-a distributions, amax

24

Very nearby MS stars: BD desert at intermediate separations?

- Set of simulated orbits: a, e, i, ω

- BD Mass function similar to SFRs

Obs

ervi

ng S

trate

gy &

Mai

n R

esul

ts (Carson et al. 2006; 2007) ‏

Inp

ut

s

Results: Statistical Analysis

MC Drawing: Comparison with detection limits & null-detection

Fraction of BD companion

Results: BD desert studies revisited for intermediate separations

fBD of 0.0 – 9.3% for a =[25 – 100] AU

RV: fBD < 1% for a < 3 AU (Marcy & Butler 2000)‏

> no significant conclusion about the BD desert extension

- Difference in the companion fraction between stellar/BD companions?

- Efficiency of the Acretion/ejection BD mechanism (Reipurth & Clarke 2001)?

Outline







25

Con

clus

ions

& P

ersp

ectiv

esConclusions

- HC and HAR Direct Imaging: - complementary to other techniques (RV, transit...) ‏

- Spectral characterization, orbit monitoring

- Missing link between 5 – 500 AU

- Impressive evolution: - Technique: telescope, AO, observing modes

- Target selection (Young, nearby associations) ‏

- Key results: - increasing number of substellar companions since 1995

- Importance of atmosphere and evolution models

- access to planetary mass companions

> raising questions related to fomation mechanisms

- Interpration of survey detection limits

> outer part of planetary systems

> constraints for planetary and BD formation scenarii

Con

clus

ions

& P

ersp

ectiv

es

Perspectives

- Upcoming:

NTT/Sofi, HST/NICMOS, GDPS-ADIGemini/NICI, VLT/NACO SACY surveyAEOS/Lyot project

- Horizon 2010

Subaru/HiCIAOGemini Planet ImagerVLT/SPHERE

> Session (tomorrow): Futur Instruments & Telescopes

planets & brown dwarf...

Documents