TW Hydrae: multi-wavelength interferometry TW Hydrae: of a transition disk multi-wavelength interferometry Jonathan Menu of a transition disk Intro TW Hydrae
High resolution study Jonathan Menu Discussion
Conclusions Institute for Astronomy (IvS) KU Leuven, Belgium
R. van Boekel, T. Henning (MPIA) M. Benisty (IPAG) C. Chandler (NRAO) C. Waelkens (IvS)
1 / 19 ? ? TW Hydrae: Protoplanetary disks multi-wavelength The Astrophysical Journal, 745:5 (12pp), 2012 January 20 Krausinterferometry& Ireland of a transition disk LkCa 15 Jonathan Menu
(Kraus & Ireland 2012) Intro
TW Hydrae
High resolution study
Discussion
Figure 3. Left: the transitional disk around LkCa 15, as seen at a wavelength of 850 µm (Andrews et al. 2011). All of the flux at this wavelengthConclusionsis emitted by cold ∼ dust in the disk; the4 deficit in the center denotes an inner gap with radius of 55QuAUan.zR eight:t al.an expanded view of the central part of the cleared region, showing a composite of two reconstructed images (blue: K′ or λ = 2.1 µm, from 2010 November; red: L′ or λ = 3.7 µm, from all epochs) for LkCa 15. The location of the central star is also marked. Most of the L′ flux appears to come from two peaks that flank a central K′ peak, so we model the system as a central star and three faint point sources. HD 100546 3.2. Orbital, Morphological, and Atmospheric Properties a spatially resolved region, then it could be subject to two (Quanz et al. 2013) uncertainties. Since we are fitting a potentially resolved source The observed morphology of LkCa 15’s candidate companion as a point source, model mismatch could cause systematic is more complicated than that of older directly imaged exoplan- astrometric errors. More seriously, if the emission comes from ets, which are seen as unresolved point sources (Marois et al. an extended dusty structure, then the centroid of the emission itself could change (with respect to that structure’s position) 2008; Kalas et al. 2008; Lagrange et al. 2009). The flux is mostly ′ concentrated in a single unresolved location at 2.1 µm, but it is over time. Even if the dust producing the L emission is orbiting clearly extended at 3.7 µm. The most simple interpretation is at a Keplerian velocity, the emission from different points in the that the central source is therefore a newly formed exoplanet, structure might wax or wane. A conservative estimate of orbital which emits significant flux at 2.1 µm due to either a warm motion should be based on at least several additional epochs, atmospheric temperature or accretion of hot material. The sur- in order to determine the residuals around its apparent orbital rounding 3.7 µm dominated emission would then trace extended velocity. circumplanetary material, most likely as it is accreting down to The observed contrasts can be converted into absolute the planet, though perhaps as it accretes past the planet and onto magnitudes using the observed photometry for LkCa 15 A ± the inner disk (e.g., Dodson-Robinson & Salyk 2011). We can (Appendix) and the distance to Taurus–Auriga, 145 15 pc Fig. 2.— The HD100546 disk on different scales. In the HST/A(TCSorresimage eotbtail.ned2009in th);e Fthe814Wcombinedfilter (left) tabsolutehe circumstmellagnitudeer disk and extrapolate thearorbitalound HDr100546adii, absolutecan be tramcedagnitudes,out to a fewandhundcolorsred AUoifn scattered light (Ardila et al. 2007). The inner disk regions ( 1′′ in radius) ′ = ∼ ± these structuresarefromhiddenour behglobalind the cfitoroofnagallraphobservor suffaetionsr from (TPSableF sub2tr,action rcoloresidualsfor. Thaellpothreelarizaticomponentson fraction imagaere(leMft)Lobtaine6d.8at th0e .V2LTmag and in PDI mode in the H band (Quanz et al. 2011b) probes regions veKry ′c−loseLt′o=the1.s7tar±, e0na.2blimngag.theYdoungetectionhot-startof disk aspylanetsmmetriesshouldnot have ? ? bottom section)acceusingssible wtiheth oapparentther imagingmagnitudes,techniques. Thdeistance,position oandf the planet candidate is overlaid in the PDI image. North is up and east to the Protoplanets age for LkCa 15left winTransitionhich both iwemagdescribees. further in Appendix disks. SEDs similar to L dwarfs, so assuming an approximate tempera- We converteddiskthe surfaobservce wase sdmooseparationth and azimanduthaPlly.A.syformmeeachtric, the turebeofr t1500ranslaKtesandintoappropriate a probabilitbolometricy of having correctionssuch a physi-(Leggett ⇒ disk image shown in Figure 2 should be mirror symmet- et cal.ally2002unre),lathented sotheurcecorrespondingin a 1′′ 1′′ fiebolometricld of view alruminosityound is source into a deprojected orbital radius using the observed −3 5 × ric with re◦spect to the dis◦k minor axis running with a L the=st2ar×of10p = 1L.3⊙,10w−ith. Fanuruncertaintythermore, theoffaatctleast that tahfeactor of disk geometry (i = 49 ,P.A. = 241 ;Andrewsetal.2011): bol · position angle of 48◦ through the image center (Quanz 2–3L (bdependingand emissioonn atheppeactualars to btemperature).e extended argues against RNE = 20.1e±t a2l..8A2011Ub,). RHCENo∼wev=er, 15the.9re±are2. c1AlearUa,syRmmSWetr=ies in a background object. 2 / 19 ◦ Since the observed flux comes from spatially resolved struc- 18.4 ± 2.6 AU.formModelof a dfitseficfitorindiskspolartizypicallyation fravcatryionbyin ∼no5–10rthern di- Disk feature: The observed L′ brightness and mini- between differentrectioobservn, i.e.,ationsalongandthe modelspositionooffthethesamedetectartedgets,object. turesmuandm lumnotinoasitsingley are dpointifficultsource,to explathenin wtheith dphyisk-sicalinternpropertiesal so we adopt aBsaystematicsed on Figuncertaintyure 2 the disofk “±ho5le◦ ”inexthetendinclination;s to larger sep- of peachrocesscomponentes alone as mustthe exbepecconsideredted temperainditureviduallyin the d. isIfkthe flux arations and appears more like a “wedge”. As discussed seenmidfrom-planetheatcentral the locastourceion of (nearthe sotheurceKis′ opeak)nly 50correspondsK combined with the distance uncertainty of ±15 pc, the total ∼ in Quanz et al. (2011b) the underlying physical reason (Mulders et al. 2011). Furthermore, we are not′ =aware ± uncertainty in deprojected radii is ∼15%. Given deprojected to the planet, then its brightness and color (MK 9.1 0.2; for this feature is not clear at the moment (e.g., drop K′o−f sLho′ c=k-p0r.98oce±sse0s.22)thatareactmoorenly consistentlocally andwithmighatphotospherelead orbital radii oinf s∼ur16–20face denAUsity,, tdhenisk stheurfacecorrespondinggeometry, chaorbitalnging dust to the observed luminosity in a disk that appears to be period and orbitalpropmerotionties). aHroundowevera, sfindolarin-typeg an astarsymmareet∼ry90atyears this spe- thannotwithverywmaarmssivdust.e. If Fitorwagesas scaoftte1reMd ligyrh ort t5haMt wyre (bracksee, eting and ∼4 deg yearcific−lo1.caOtiournastrometricrenders plaupsrecisionible a phforysicathel lincentralk between theo1nσe wlimitsould eonxptheectage thatofalsLkCao in t15),he NthenIR athismabrightnessximum in would source (i.e., thethosperoposedstructuresplanetand thitself)e sourceisd∼etec1◦.t5ed(for here.its K′ naisvcealytteberedconsistentlight wouldwithbe saeemn.assUsinofg6thMeJupPDorI im15agMesJupasaccord- ingtrtaocetrhefo“hotr scattstart”ered ligmodelsht we find(Chabriera localetmainl.im2000um ).heHore wever, emission), so it is plausible that4we. DIcouldSCUSSIsOeeN orbital motion as described above. at the 3σ level within the next 1–2 years. Orbit determinations if this planet is newly formed, then even the value for 1 Myr 4.1. The image of an embedded exoplanet? mightPhobeto ansphoveriecrestimate. emission:Furthermore,If the observtehed ppresenceoint sourceof signif- for other high-contrast companions (such as GJ 802 B; Ireland flux arose solely from the photosphere of a young object et al. 2008) showBatshated theon tahstrometrice object’s errorspositiopredictedn angle, thbye dNRMisk incli- icantthecircumplanetaryCOND and DUSTmYaterialmodelssuggestssuggest thatmassitesisbequitetweenlikely to nation and t′he distance to HD100546, the object’s de- be accreting,15 – 20 Mand currentfor planetan ageformationof 5 – 10mModelsyr (Bsauggestraffe that a are typically vparlid.ojecTtehed sLepaastrometryration from forthe cethentSWral stsourcear is 68might10 AU, ∼ Jupiter ∼ ± giantet aplanetl. 2003should; Chabrinterceptier et al.much2000).ofMtheodedlsiskwmithasslowthater would already be shoi.ew.,ingwithoinrbitalthe lamrgotion,e circusincemstellather disokf.fsetDiffbetweenerent scenar- specific entropy in the initial conditions for the formation ios to explain both the L band emission and the observed otherwise accrete onto the central star (Lubow & D’Angelo 2009 and 2010 is almost entirely in the P.A. direction and has process predict even higher masses (cf. Spiegel &−7Burr−o9ws −1 2006; Machida et al. 2010), typically M˙ = 10 –10 M⊙ yr a magnitude ofdisk1.7 strσu.ctHuroew ceavner b,eiafsstehesseemissiond: comes from 2012). Classical binary formation via core fragmentation Background source: A background source would be ob- or formation via disk instability when the disk was still served through the HD100546 disk. Based on the disk 7 massive would be the preferred formation mechanisms model presented in Mulders et al. (2011) background for an object of this mass. In this case the object formed flux in the L band should be attenuated by a factor of 3 7 roughly coeval with the star and would have had time 6.7 10− 5.4 mag at a location of 70 AU . Taking ∼ · ≈ ∼ to significantly alter the structure of the main disk, e.g., this factor into account we used the Besancon galactic dynamically clearing a large azimuthal gap, which has model (Robin et al. 2003) to estimate the number of ob- not been observed. jects in the apparent magnitude range 7 mag L 9 Ejected planet: Another massive planet is thought to mag. This yielded 330 objects in a 2 squar≤e deg≤ree ∼ be orbiting in the inner disk gap (e.g., Acke & van den patch on the sky centered around HD100546. This num- Ancker 2006; Tatulli et al. 2011) and we speculate that 7 This factor does not include that the object is seen through an dynamical interactions between multiple planets and the inclined disk which would yield an even higher optical depth. disk could have led to an ejection event. The emission TW Hydrae: TW Hydrae multi-wavelength interferometry of a transition disk
“TW Hydrae may become the Rosetta stone for our Jonathan Menu understanding of the evolution and dissipation of Intro protoplanetary disks.” (Calvet et al. 2002) TW Hydrae
High resolution study
Discussion TW Hya: Conclusions
I closest accreting T Tauri star
I disk oriented pole-on, Rout > 200 AU I inner gap Fig. Hubble 1.1-µm image (Weinberger 1999)
3 / 19 TW Hydrae: One decade of “hole” models multi-wavelength interferometry of a transition disk
Calvet et al. (2002) Ratzka et al. (2007) Jonathan Menu SED SED + MIDI Intro
TW Hydrae
High resolution 4 3.2AU4" study 0.72.17 AU" Discussion
Conclusions
Akeson et al. (2011) Arnold et al. (2012) SED + MIDI + VLA SED + mid-IR speckle self-luminous source?
3.52.73 "AU 0.52.21 AU"
4 3.2AU4" 4 3.2AU4"
Fig. Overview of proposed disk models
4 / 19 TW Hydrae: Motivation multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro Decade of high spatial resolution studies TW Hydrae still not clear how inner disk is shaped High resolution ⇔ study Problems: Discussion Conclusions I an sich: what is the disk structure?
I inner “hole”: processes determining disk dispersal, physics of planet formation?
I modeling of the gas (H2O, Hogerheijde et al. 2011; HD, Bergin et al. 2013): radiation budget determined by dust, “boundary condition” for gas dynamics/chemistry
5 / 19 TW Hydrae: Data multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro
TW Hydrae
High resolution study
Discussion High angular resolution from near-infrared to millimeter Conclusions (credits: ESO, SMA, VLA)
instrument wavelength data VLTI/PIONIER 1.6 µm (H-band) near-IR interferometry VLT/NACO 3.6 µm (L-band) sparse aperture masking VLTI/MIDI 10 µm (N-band) mid-IR interferometry SMA 870 µm sub-mm interferometry EVLA 9 mm mm interferometry
6 / 19 TW Hydrae: Old models and new data multi-wavelength interferometry SED SMA of a transition disk SED SMA 2.0 Calvet02 Calvet02 Jonathan Menu Calvet02: separated Ratzka07 Ratzka07 10-12 Andrews12 Andrews12 1.5 Intro 10-13 TW Hydrae ) -14 2 10 1.0
(W/m High resolution 10-15 (Jy) flux λFλ study 0.5 10-16 Discussion
10-17 0.0 Conclusions
10-18 100 101 102 103 104 0 100 200 300 400 500 600 wavelength ( m) UVdist (kλ) MIDI EVLA
MIDI 50m EVLA 1.0 0.0025 Calvet02 Calvet02 Ratzka07 Ratzka07 Andrews12 0.0020 Andrews12 0.8
0.0015 0.6
0.0010 flux (Jy) flux visibility 0.4 0.0005
0.2 0.0000
0.0 −0.0005 8 9 10 11 12 13 0 500 1000 1500 2000 wavelength (µm) UVdist (kλ)
7 / 19 TW Hydrae: Old models and new data multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro
TW Hydrae
High resolution 4 conclusions: study 1. large grains ( µm) Discussion 2. importance of full radiative transfer Conclusions 3. SED modeling degenerate: different models 4. special care in mm: old VLA data (Hughes et al. 2007) new EVLA data ↔
8 / 19 TW Hydrae: Modeling multi-wavelength interferometry of a transition disk
Jonathan Menu
Radiative transfer code + genetic fitting algorithm: Intro
I generations of models, only best models kept for TW Hydrae High resolution offspring generation study I offspring: random models in neighborhood of parents in Discussion parameter space Conclusions
Select random Calculate Choose random para- Select best End of combinations of corresponding meters in neighbor- models iteration parameters models [parent selection] hood selected models [final model] [initial population] [model generation] [child population]
Fig. Genetic-algorithm principle
9 / 19 TW Hydrae: Modeling: 3 steps multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro
TW Hydrae
High resolution 1 2 3 study Discussion
Conclusions
Largest grains
Fig. Three steps in model refinement
10 / 19 TW Hydrae: Modeling: 3 steps multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro
TW Hydrae
High resolution 1 2 3 study Discussion
Conclusions
Largest grains
Fig. Three steps in model refinement
11 / 19 TW Hydrae: 1. Simple disk multi-wavelength interferometry of a transition disk
Jonathan Menu
Intro
TW Hydrae
High resolution study
Discussion
Conclusions
Fig. Fit parameters: Rin, Rout, Mdust, p, amax, α
12 / 19 TW Hydrae: 1. Simple disk multi-wavelength interferometry of a transition disk SED SMA 1.5 SED SMA Jonathan Menu simple disk simple disk 10-12
1.0 10-13 Intro )
2 -14 TW Hydrae
− 10 0.5 (W m (W flux (Jy) flux λ 10-15 High resolution λF study 10-16 0.0 Discussion 10-17 Conclusions 10-18 −0.5 10-1 100 101 102 103 104 0 100 200 300 400 500 600 wavelength ( m) UVwave (kλ)
MIDI EVLA 1.0 0.004 MIDI 00m EVLA MIDI 25m simple disk MIDI 50m 0.8 simple disk 0.003
0.6 0.002 flux (Jy) flux (Jy) flux 0.4 0.001
0.2 0.000
0.0 −0.001 8 9 10 11 12 13 0 500 1000 1500 2000 wavelength (µm) UVwave (kλ) −4 Fig. Parameters: R = 0.71 0.06 AU, Rout = 58.1 1.9 AU, M = (1.8 0.4) 10 M , in ± ± dust ± × −5 p = 0.29 0.14, amax = 1 cm, α = (1.0 0.5) 10 ± ± × 13 / 19 TW Hydrae: 3. Simple disk + rounded rim multi-wavelength interferometry + compact distribution of large grains of a transition disk Jonathan Menu
Intro
TW Hydrae
High resolution study
Discussion
Conclusions
Largest grains
Fig. Fit parameters: Rin, Rout, Mdust, p, α, Rexp, w, plarge 14 / 19 TW Hydrae: 3. Simple disk + round rim + compact distr. large grains multi-wavelength interferometry SED SMA 1.5 of a transition disk SED SMA simple disk simple disk 10-12 final disk final disk Jonathan Menu
1.0 10-13 Intro )
2 -14
− 10 0.5 TW Hydrae (W m (W flux (Jy) flux λ 10-15 λF High resolution 10-16 0.0 study
10-17 Discussion
10-18 −0.5 10-1 100 101 102 103 104 0 100 200 300 400 500 600 Conclusions wavelength ( m) UVwave (kλ)
MIDI EVLA 1.0 0.004 MIDI 00m EVLA MIDI 25m simple disk MIDI 50m final disk 0.8 simple disk 0.003 final disk
0.6 0.002 flux (Jy) flux (Jy) flux 0.4 0.001
0.2 0.000
0.0 −0.001 8 9 10 11 12 13 0 500 1000 1500 2000 wavelength (µm) UVwave (kλ) −4 Fig. Parameters: R = 0.48 0.08 AU, Rout = 62.0 0.6 AU, M = (1.2 0.4) 10 M , in ± ± dust ± × −5 p = 0.7 0.1, amax = 1 mm, α = (1.0 0.5) 10 , Rexp = 3.8 0.5 AU, w = 0.45 0.05, ± ± × ± ±
plarge = 1.4 0.1 ± 15 / 19 TW Hydrae: Discussion multi-wavelength interferometry of a transition disk
Jonathan Menu
Rim shape? Intro TW Hydrae 3! High resolution 1 R/Rexp study Σrim = exp − Σdisk − w Discussion Conclusions HD 100546 (Mulders et al. 2013b):
I observations + hydro simulations of rim shape
I agreement if 60 MJ brown dwarf
TW Hya: shape in agreement with this profile, companion within central 0.5 AU? ∼
16 / 19 TW Hydrae: Discussion multi-wavelength interferometry of a transition disk
Decoupling between different grain sizes? Jonathan Menu
Intro Process of dust growth (Birnstiel et al. 2012): TW Hydrae I after few Myr: largest High resolution study grains in inner region R−1.5 Discussion 1.5 I Σdust R− : Conclusions dust
∝ Σ fragmentation-limited R−0.75 0.75 I Σdust R− : drift-dominated∝
R This study:
I centrally concentrated large-grain population 1.4 0.1 I large grains (> 100 µm): Σdust R− ± ∝ 0.7 0.1 I small grains (< 100 µm): Σdust R ∝ − ±
17 / 19 TW Hydrae: Discussion multi-wavelength interferometry Final disk structure? of a transition disk Jonathan Menu Calvet et al. (2002) Ratzka et al. (2007) SED SED + MIDI Akeson et al. (2011) Arnold et al. (2012) SED + MIDI + VLA SED + mid-IR speckle self-luminous source? Intro TW Hydrae 4 3.2AU4" 0.72.17 AU" 3.52.73 "AU 0.52.21 AU"
4 3.2AU4" 4 3.2AU4" High resolution study
Discussion Current best model Conclusions
0.48 ± 0.08 AU
3.8 ± 0.5 AU
18 / 19 TW Hydrae: Summary multi-wavelength interferometry Radiative transfer modeling of multi-wavelength data at of a transition disk Jonathan Menu highest resolution: Intro
TW Hydrae
1. automatic fitting High resolution study
Discussion 2. models confirm earlier scales, integrate data at all Conclusions wavelengths
3. rim in agreement with profiles from hydrodynamical simulations, link with sub-stellar companion
4. separated large-grain population, limiting dust-growth regimes
???
19 / 19