The inner rim of 51 HAeBe protoplanetary disks.

Transcription

1 The inner rim of HAeBe protoplanetary disks. A VLTI-Pionier survey Lazareff et al. ESO Large Program #9C-963 B. Lazare, J.-P. Berger 2,, J. Kluska 3, J.-B. Le Bouquin, M. Benisty, F. Malbet, C. Koen 4, C. Pinte 6, W.-F. Thi 7, O. Absil, F. Baron 8, A. Delboulbé, G. Duvert, A. Isella, L. Jocou, A. Juhasz 9, S. Kraus 3, R. Lachaume, 2, F. Ménard, R. Millan-Gabet 4,, J. Monnier 3, K. Perraut, F. Soulez 6, 7, M. Tallon 6, E. Thiébaut 6, W. Traub 8, and G. Zins 9

2 The structure of a disk inner rim Dullemond & Monnier 2 Questions: Magnetospheric accretion Accretion shock Dust-free inner gas disk Rounded off dust inner rim: a dust chemical reactor Radial structure Vertical structure Optically thick gas (?) Shadow cast by the gas (?); a possible safe haven for dust Near-IR-emitting surface of the dust inner rim Weak shadow cast by the dust rim (?) Dust temperature Dust composition Non axi-symmetry

3 A VLTI-PIONIER large program m H PIONIER: 2 4 Telescopes, 6 and 6 closure phases H band:.6 m, peak K at 2.2 mic, dust sublimation m baseline, 3mas, 3 pc B A F G 3 AT Nights HD SAMPLE: H AeBe (Hillenbrand.92, Thé94, Malfait98) 4 Non binary 26 High Quality Additional Photometry νf ν (erg cm 2 s ) 9 Usno Tycho 2mass Wise Exp Tanni SaVis2 SaIr2 Litterature + UBVRIJHK (SAAO Sutherland) λ (µ)

4 An example of HQ Pionier data.9 e Extended flux HD43.8 Wagner et al Resolved inner rim.3.2 sh c.d. s Unresolved stellar flux Mλ Chromatic dispersion: Temperature difference between star/hot dust

5 Table 8: Parameters for ring fits. Redundant parameter fs is also included, see Table 6 kc fc fh flor la lkr cos i A&A proofs: manuscript no. HAeBeLP_master ck, sk spectral index of circumstellar component fractional flux of circumstellar component fractional flux of halo component weighting for radial profile (log) half light semi major axis (log) ratio (kernel radius) / (ring radius) axis ratio of isophotes position angle of major axis, East from North cosine and sine amplitudes for mode k our goal is not to fineit represents reality; a ments on some large-s Parametric fitting: the method HD Ring m= Ring m= star HD3964 RingM fully resolved component (k) RingM Power law with inner boundary In some, if not all, current2 models for inner disk rims, one expects the brightness distribution to have a sharper cuto inwards we tested models with a radial disthan outwards. Accordingly, tribution: 2 ( if r < ar F (r) = ar 3 (9) r if r ar 4 2 ring of variable width (up to no ring at all).6 φc (o) HD Fig. 7: Examples of(l) model fits, showing four objects and fit results at four levels of complexity of the fit model Ring m= Temperatures from φc (o) Ellipsoid.6 2 φc (o) 2 RingM HD46 3 RingM φc (o) HD Dust temperatures HD HD 4677 HD 43 we discuss our sampl ties, which makes the not implying that real.2 Azimuthal modulation allowed to reproduce radiative transfer effects.2 and similar models with an exponent di erent from 3, or an ex- Figure 8 shows the histogr to fd >. to exclude obje meaningful. The histogram above 22K or below 2 of such outliers, we make The median value o 3.22). The median of th.26, consistent with an median log (T dp ) med dispersion being mostly fr The median value for sublimation temperatures regarding disks around HA (2) and references ther Königl (22). However, i exist over a range of tempe ature; furthermore, our fit bias. To address these tw diative transfer code to ge (SED) from a few simple two spectral types (for the The inner rim radius of ea imum grain temperature w tion temperature T sub for silicates, and 8K for c discuss dust temperatures, subsection 4.2. The values K) are used as input to th for deriving T dp from the Fig. 9. The results are sum T d,fit are plotted on Fig. 8; to agree better with the ob ence in log T dp betwee is 2.7 times larger than th We conclude that:

6 Dust temperature Temperature extracted from single BB fit to SED: 6 K Models Tsub K Models Tsub 8K In reality spread of Temperature below T sub 8 6 Fit on synthetic SED shows peak temperature correspond to dust rim Temperature of ~8 K T dp Favours carbon grains (big?) 3.4 Interferometric temperatures systematically lower log (T di ) Additional unresolved component not taken into account? log (T dp )

7 The radius luminosity relation RadiusLuminosity RingM.pdf HD4677 HD973 a t (au) HD3786 HD98922 MWC8 VV_SER AB_AUR HD8647 HD43 HD44668 HD63296 HD46 HD3964 HD44432 HD478 HD9748 HD4227 HD93 HD42666 HD8643 HD6942 HD2943 HD988 HD867 MWC297 HD log (L bol /L ) One possible reference radius-luminosity relation: Tsub ~8 K High cooling efficiency: (big grains) Backwarming coefficient: Cbw ~

8 RingM HD The width of inner rim.6.4 φc (o) HD w = ring radius / half light A&A radius.2 manuscript proofs: w = -> nor ring or ring not resolved w a (mas) Some objects do want rings(c) (w <.) preferfitfat ones Fig. 3:but Parametric results for(w the>.) 26 HQ objects. Normalized ring fitting width wprocess? versus half flux radius a. See text. is it a result of the Article number, page 34 of 43page.43

9 .2 χ2r(m=2) / χ2r(m=) The width of the inner rim.6 χ2r Ratio.8 Method: fitting of a population of MCFOST models at different distances and inclinations (Pinte 26) w Pure ellipsoids z (au) max T : B. Lazare et al.: Few pu ed-up rims found in large interferometric survey of Herbig A LP (HQ) impact visibilities to first order; (b) a ects the phase c in.3 Fig.. G. thm Conversely, an m=2 8 modulation (alone) a ects(above) visibili and t ell.2 6 files; in the c not closures, to first order. ature distribu 4. The values of the three models listed in Table onto that for ar 2 =.6µm a (mas) pared in Fig., with the un-modulated model serving low brightnea square root s erence. r (AU) As in Fig. 2, the objectsαare off (mas) ordered by object increas locate Fig. 4: Similar to Fig. 3, but with fits of Mcfost models in, thm (value of a). One can see that most, but not all, of the and ell added. thm resolved objects show improvement of 2. model; inspired by Tannirkulam Harries though Monnier we cannot 27 when comparemod one-to the "real" width (if only because is introduced; m = modulation seems to make a di tion for the latter), this plot make more than m = 2. of the LP objects are wider than t z (AU) HD2943 HD436 HD867 HD6942 HD8643 HD9748 HD988 HD42666 VV_SER HD4227 HD44432 HD3964 HD478 HD3786 HD8647 HD973 HD93 HD98922 HD44668 AB_AUR MWC8 HD63296 MWC297 HD46 HD43 Fig. : Improvement of 2 6 (or lack of-) when increas 4 number of azimuthal modes in the fit model, the 2 c 2 ing both the terms from and cp. Note that, in contra Fig. 2, the 2 for the un-modulated ring model includes r (au) α off (mas) sure residuals, to be comparable4 toinc; the.6µm other two fit mode 8 azimuthal modulation max T, smallest to largest grains in model; inspired by Isella + Natta δ off (mas) δ off (mas) 4 inc;.6µm HD4677

10 The vertical structure i max f NIR π = θ 2 Ω fbol = = sinθ 4π Statistics of inclination Statistics of reprocesses flux non Bin (Ellipsoid) HQ (Ring) 9 8 non Bin non Bin f rep = L NIR,d / L bol, cos(i) f rep = L NIR,d / L bol, B B A A F F Spectral type Observed statistics corresponds to z / r τ = Observed statistics corresponds to z / r ~.44

11 Wrap up: scientific results Kama et al. 29 edge has sub ~ 8 K.. large carbon grains Few objects fully resolved Radius-luminosity correlation confirmed Ring structure is found in % of object when resolved Wide rings are favoured (consistent with latest physical models Tannirkulam 7, Kama 9, Turner 4 Flock 6) Thickness z/r ~.2 near rim larger than ~. expected (Vinkovic 24) Evidence for substantial flaring Halo component correlates with Herbig class he central region of the dusty Herbig disk with (left to right) no magnetic support, magnetic support Turner et al. 24