Cavity and other radial substructures in the disk around HD 97048

Abstract

Context. Gaps, cavities and rings in circumstellar disks are signposts of disk evolution and planet-disk interactions. We follow the recent suggestion that Herbig Ae/Be disks with a flared disk harbour a cavity, and investigate the disk around HD 97048. Aims. We aim to resolve the 34± 4 au central cavity predicted by Maaskant et al. (2013) and to investigate the structure of the disk. Methods. We image the disk around HD 97048 using ALMA at 0.85 mm and 2.94 mm, and ATCA (multiple frequencies) observations. Our observations also include the 12 CO J=1-0, 12 CO J=3-2 and HCO + J=4-3 emission lines. Results. A central cavity in the disk around HD 97048 is resolved with a 40-46 au radius. Additional radial structure present in the surface brightness profile can be accounted for either by an opacity gap at 90 au or by an extra emitting ring at 150 au. The continuum emission tracing the dust in the disk is detected out to 355 au. The 12 CO J=3-2 disk is detected 2.4 times farther out. The 12 CO emission can be traced down to ≈ 10 au scales. Non-Keplerian kinematics are detected inside the cavity via the HCO + J=4-3 velocity map. The mm spectral index measured from ATCA observations suggests that grain growth has occurred in the HD 97048 disk. Finally, we resolve a highly inclined disk out to 150 au around the nearby 0.5 M binary ISO-ChaI 126. Conclusions. The data presented here reveal a cavity in the disk of HD 97048, and prominent radial structure in the surface brightness. The cavity size varies for different continuum frequencies and gas tracers. The gas inside the cavity follows non-Keplerian kinematics seen in HCO + emission. The variable cavity size along with the kinematical signature suggests the presence of a substellar companion or massive planet inside the cavity.

Homogeneous Analysis of the Dust Morphology of Transition Disks Observed with ALMA: Investigating Dust Trapping and the Origin of the Cavities

“…cavity, in some cases showing almost a perfectly symmetric radial ring, and in other cases where the inner or the outer edge of the ring is very truncated. In the context of our models, r peak corresponds to the cavity size when comparing with observational analysis by, for example, Andrews et al (2011) and van der Marel et al ( , 2018, who fit the dust morphology by assuming a sharp edge of the dust density at the cavity location. The second motivation to use r peak as the cavity size is that the models of dust trapping predict well the location of the pressure maximum (the peak of the millimeter emission), and this has been used to infer planet properties such as planet mass and position (e.g., de Juan Ovelar et al 2013).…”

“…This is the case for the TDs around TW Hya, HD 169142, HD 97048 (e.g., Andrews et al 2016;Walsh et al 2016;Fedele et al 2017;van der Plas et al 2017b). In other cases, TDs have shown astonishing single high contrast asymmetries (e.g., HD 142527 and IRS 48, Casassus et al 2013;van der Marel et al 2013), or more complex structures such as spiral structures (e.g., AB Aur, Tang et al 2017), or a combination of single rings and crescent structures, such as the TD around MWC 758 and V1247 Orionis (Boehler et al 2017;Kraus et al 2017).…”

“…The sample includes the following disks: J16083070-3828268 (hereafter J16083070), RY Lup, Sz 111, Sz 100, J16070854-3914075 (hereafter J160708), Sz 118, and Sz 123A from the most recent survey of the Lupus star-forming region (Ansdell et al 2016). From this region, there are other disks with tentative cavities (Tazzari et al 2017;van der Marel et al 2018), but they are excluded from the sample since the cavity size remains unconstrained from our visibilities analysis, as explained in Section 4. From the most recent ALMA survey of the Upper Sco star-forming region, we perform our visibility analysis for all the potential TDs reported in Barenfeld et al (2016), which may show a clear null at the interferometric visibilities as evidence for the existence of a cavity (e.g., Hughes et al 2007).…”

“…However, in our sample, we keep the TDs whose asymmetries are low contrast or are debatable (e.g., SR21, HD 135344B, and HD 34282, Pinilla et al 2015c;van der Plas et al 2017a). In general, our interest is focused on large axisymmetric cavities.…”

1000 au exterior arcs connected to the protoplanetary disk around HL Tauri

“…Observations in (sub-)millimeter continuum at spatial resolutions of a few au and high-contrast imaging at infrared have revealed rings and gaps with widths of few au to tens of au in several protoplanetary disks (Akiyama et al 2015;Momose et al 2015;Rapson et al 2015;Isella et al 2016;Andrews et al 2016;Ginski et al 2016;Konishi et al 2016;Perrot et al 2016;van der Plas et al 2017). The presence of these gaps suggests decreases in surface density or changes in dust properties at the location of these gaps (Takahashi & Inutsuka 2014;Dipierro et al 2015;Dong et al 2015Dong et al , 2016Kanagawa et al 2015Kanagawa et al , 2016Tamayo et al 2015;Zhang et al 2015;Jin et al 2016;Okuzumi et al 2016;Dong & Fung 2017).…”