RESEARCH HIGHLIGHTS
Jochen Stadler, PhD student, found a strong localized non-Keplerian feature within the dust cavity of a transition disk as well as a tightly wound spiral extending over 300 degrees in azimuth. We interpret both features as being due to an embedded companion located at the edge of the continuum ring.
Together with Carsten Dominik, Kate Follette, Antonio Garufi, Christian Ginski, Jun Hashimoto, Miriam Keppler, Willy Kley and John Monnier, we wrote a review for the series of chapters for the Protostars & Planets VII conference on "Optical and Near-infrared View of Planet-forming Disks and Protoplanets". We dedicated this work to our co-author Willy Kley, whose unique contributions to our field, optimism and kindness will be remembered for a long time.
We detected a clear signature of a circumplanetary disk around the planet PDS70c. This is the region where satellites form. With ALMA we found emission from dust co-located with PDS70c, and could determine that it has at least the mass needed for 3 Moons, and a radius smaller than 1 astronomical unit. Check out the press release and a few press articles (NYT, CNN, Science Mag, Reuters, Nat Geo). We also did a few interviews, including the SETI live.
2020 saw the first results of the DESTINYS Large Program that will target 85 young disks in nearby star forming regions. We are 60% through the program, and our objective is to assess the statistical prevalence of substructures in disks by probing a large and complete sample. Our first observations allow us to study the interplay between infalling material in the outer disk regions and misalignment of the inner disk in the SU Aur object. A beautiful DESTINYS result led by Christian Ginski, and also check the press release.
A year ago, a bunch of us met at the Flatiron Institute to brainstorm on how planet-disk interactions affect the gas velocity field, and how to best design observing programs to detect embedded planets in disks using ALMA data. An extensive summary of our discussions can be found in this white paper put together by Rich Teague.
My PhD student Marion Villenave published a beautiful analysis of very inclined and edge-on disks with Francois Menard, Bill Dent and colleagues. The image on the left shows the scattered light image of a disk obtained with HST, and in white contours that same disk as it appears in the millimeter continuum ! Fascinating! This indicates extremely efficient settling and radial drift of large dust grains. This is only the first part of the analysis as all these disks were also observed in gas tracers ! Find the paper here!
With Miriam Keppler, we look at a fascinating circumbinary disk, GG Tau, that shows spirals, streamers, and shadows. The streamer-like filaments appear to connect the outer ring with the northern arc and their spacing suggests that they may be generated through perturbations by the binary, which tear off material from the inner edge of the outer disk once during each orbit. This work was supported by hydrodynamical simulations by Anna Penzlin. Check the paper here!
Stefano Facchini discovered that two transition disks host multiple structures! How exciting! These disks have large cavities, likely carved by Jupiter-mass planets, and these new substructures tell us that there might be at least another planet out there. These rings might be favorable locations for second generation planet formation. The paper also presents hydrodynamical simulations by Jaehan Bae that show the choice of the disk cooling timescale can significantly impact the structure and observables of gas and dust. Paper here!
Together with Gabriela Muro-Arena, we recently published a scattered light image of a shadowed protoplanetary disk HD139614 observed with SPHERE. With radiative transfer simulations, we found that we could reproduce the very broad shadow only when considering multiple misalignments with disk regions. Check the paper here!
Gabriela also recently published a beautiful image of the SR21 transition disk showing spirals within a large cavity, see the paper here!
With Giovanni Rosotti and Attila Juhasz, we detected evidence for spiral arms in the thermal emission of HD100453. The spirals arms in the ALMA data show a smaller opening angle than the ones in scattered light, supporting a significant temperature variation between the midplane and the surface layers. The paper will soon be published in MNRAS.
2018 has seen the discovery of the first robust detection of proto-planets still embedded in their host disk: PDS70b and c. Since our original discovery, we have led other works to characterize this unique object. We looked at its thermal emission and found evidence for a continuum emission co-located with PDS70c. The system appears stable with the two planets in mean motion resonance. These papers were led by Miriam Keppler, Andrea Isella, and Jaehan Bae, and can be found here and here and here!
Together with Paola Pinilla, we looked at a fascinating transition disk (SR24) with ALMA at 3 different wavelengths, and detected an inner disk of large dust within a large cavity, likely carved by a planet or a massive companion. The paper is published in ApJ.
With Marion Villenave, we looked at the spatial distribution of small and large grains in two transition disks observed with SPHERE and ALMA, and found clear segregations both radially and vertically. These results are consistent with efficient settling of grains, and with dust trapping by planetary companions. The paper was published in A&A.
The Disk Substructures at High Angular Resolution Project (DSHARP ALMA Large Program) released all science ready data and 10 publications. At the Universidad de Chile, with Laura Pérez, we looked in details at a disk with evidence for inner disk misalignment and with Nicolas Kurtovic (now PhD student at MPIA with Paola) at multiple systems.
With Miriam Keppler and a large team of co-authors, we detected the first baby exoplanet, still in its nursery: PDS70b !
It's a massive planet carving a large gap in a protoplanetary disk.
The planet was further characterized by Andre Muller.
