exoALMA. XXIII. Estimating Disk and Planet Properties from Dust Morphologies with DBNets 2.0

Journal article

The exoALMA large program provided an unprecedented view of the morphologies and kinematics of 15 circumstellar disks, offering a biased but homogenous and well-characterized sample for population-level analysis. Continuum observations revealed numerous dust substructures, known to be potential signatures of embedded planets. We analyze the observed dust morphologies with the simulation-based inference tool DBNets2.0, assuming these are due to embedded planets at fixed locations, to infer the system’s properties. We estimate the putative planet mass, the disk α viscosity, scale height, and dust Stokes number that would reproduce 19 substructures in 13 of the 15 exoALMA disks. We compare our results with literature estimates derived with different methods, and find good agreement in most cases. We further explore the implications of the inferred disk properties for accretion, showing that for the Herbig stars in our sample, the implied viscous accretion timescales are too long to account for their observed stellar accretion rates. Regarding planet migration, our results favor inward migration, with only three putative planets expected to migrate outward. Finally, we check for correlations of the inferred disk and planet properties with the disks’ gas-to-dust mass ratio, nonaxisymmetry index, and masses of the gas, dust, and host stars, finding no remarkable trends.

Authors: Ruzza, A; Lodato, G; Rosotti, G; Armitage, P; Facchini, S

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: American Astronomical Society
• Journal: The Astrophysical Journal Letters
• Volume: 1000
• Issue: 1
• Pages: L16
• Article number: L16
• Publication date: 2026-03-16
• Acceptance date: 2026-02-05
• DOI: 10.3847/2041-8213/ae434c
• EISSN: 2041-8213
• ISSN: 2041-8205
• Language: English
• Keywords: Astronomy image processing; Astronomy data analysis; Protoplanetary disks; Planetary system formation