What the study found
Large protoplanetary disks in the exoALMA sample commonly show deviations from smooth Keplerian rotation, and these deviations appear in several different forms. The authors report spiral-like structures, arc- or ring-like features, and patterns consistent with changes in the emitting surface height.
Why the authors say this matters
The study suggests that deviations from Keplerian rotation in disk gas kinematics are key tracers of physical processes and the presence of protoplanets within disks. The authors conclude that their 2D atlas provides a first systematic and uniform overview of gas substructures across the full exoALMA sample.
What the researchers tested
The researchers used CO (carbon monoxide) J = 3–2 data from the exoALMA Large Program, covering 15 disks. They built two-dimensional maps of centroid velocity, line width, and peak intensity, then extracted non-Keplerian deviations by subtracting smooth Keplerian models.
What worked and what didn't
All targets showed large-scale deviations from smooth Keplerian disks. Nonaxisymmetric spiral-arm features were detected or suggested in five disks: CQ Tau, MWC 758, HD 135344B, HD 34282, and SY Cha, and these were preferentially found in Herbig Ae/Fe systems. Some other sources, including J1852, PDS 66, and V4046 Sgr, also showed noticeable deviations but appeared to be dynamically quieter.
What to keep in mind
The summary is based only on the abstract, so no detailed limitations are described here. The authors note that the atlas is based on observations with sufficient sensitivity, moderate-to-high spatial resolution of about 20 au, and high-velocity resolution of about 0.1 km s−1, and the sample consists of 15 disks aged a few million years.
Key points
- All 15 disks showed large-scale deviations from smooth Keplerian rotation.
- The deviations included spiral-like, arc- or ring-like, and surface-height-related patterns.
- Spiral-arm features were detected or suggested in five disks: CQ Tau, MWC 758, HD 135344B, HD 34282, and SY Cha.
- Spiral-arm features were preferentially found in Herbig Ae/Fe systems.
- Some sources, including J1852, PDS 66, and V4046 Sgr, appeared dynamically quieter despite noticeable deviations.
Disclosure
- Research title:
- Large protoplanetary disks show widespread non-Keplerian gas motions
- Publication date:
- 2026-03-16
- OpenAlex record:
- View
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