Searching for Circumplanetary Dust in the Cavity of the AB Aurigae Disk with ALMA
Abstract
The young intermediate-mass star AB Aurigae is surrounded by a transition disk whose cavity contains several proposed protoplanets, including the debated source "AB Aur b" at a projected separation of ≈ 0.6 arcsec (≈ 93 au). To search for circumplanetary material associated with these candidates, we have obtained the most sensitive (∼ 20 μJy/beam rms) and highest angular resolution (∼ 30 mas) ALMA Band 7 (0.88 mm) observations of AB Aur to date. We recover the asymmetric dust ring in the continuum emission peaking at ∼ 0.9 arcsec (∼ 140 au) and compact emission at the stellar position, but detect no point source at the location of AB Aur b or any of the other proposed protoplanet candidates down to a 3σ limit of $60$ μJy. For optically thin emission, this corresponds to a dust mass of ≲ 0.0059 M⊕ (for a dust temperature of 40 K), comparable to the circumplanetary disk around PDS 70 c. The 12CO emission fills the continuum cavity, revealing inner spiral structure and a clear rotation pattern. The gas at the position of AB Aur b is smoothly connected to the ambient disk with no localized excess or obvious kinematic deviation. If any proposed candidates are accreting, their circumplanetary material must have a low dust mass, a small physical size, dust that is optically thick, or a dearth of large mm-emitting grains.
Related
- Feeding the Circumplanetary Disk: 3D Simulations of Dust Filtration and Accretion in PDS 70 c
- Mid-infrared Imaging of SR 12 c with JWST/MIRI: Grain Growth in an Evolved Circumplanetary Disk
- Mid-infrared Imaging of SR 12 c with JWST/MIRI: Grain Growth in an Evolved Circumplanetary Disk
- Young Planets around Young Accreting Stars: II. Circumplanetary Disk Formation and Accretion
- Destructuring the disk of AB Aurigae: Dynamics and accretion
BibTeX
@misc{jiang2026searching,
title = {{Searching for Circumplanetary Dust in the Cavity of the AB Aurigae Disk with ALMA}},
author = {Lillian Jiang and Brendan P. Bowler and Ya-lin Wu and Yifan Zhou},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.37792},
eprint = {2610.37792},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.37792},
}
RIS
TY - UNPB
TI - Searching for Circumplanetary Dust in the Cavity of the AB Aurigae Disk with ALMA
AU - Lillian Jiang
AU - Brendan P. Bowler
AU - Ya-lin Wu
AU - Yifan Zhou
PY - 2026
DA - 2026/10/27
PB - arXiv
DO - 10.48550/arxiv.2610.37792
UR - https://arxiv.org/abs/2610.37792
AB - The young intermediate-mass star AB Aurigae is surrounded by a transition disk whose cavity contains several proposed protoplanets, including the debated source "AB Aur b" at a projected separation of ≈ 0.6 arcsec (≈ 93 au). To search for circumplanetary material associated with these candidates, we have obtained the most sensitive (∼ 20 μJy/beam rms) and highest angular resolution (∼ 30 mas) ALMA Band 7 (0.88 mm) observations of AB Aur to date. We recover the asymmetric dust ring in the continuum emission peaking at ∼ 0.9 arcsec (∼ 140 au) and compact emission at the stellar position, but detect no point source at the location of AB Aur b or any of the other proposed protoplanet candidates down to a 3σ limit of $60$ μJy. For optically thin emission, this corresponds to a dust mass of ≲ 0.0059 M_⊕ (for a dust temperature of 40 K), comparable to the circumplanetary disk around PDS 70 c. The ^12CO emission fills the continuum cavity, revealing inner spiral structure and a clear rotation pattern. The gas at the position of AB Aur b is smoothly connected to the ambient disk with no localized excess or obvious kinematic deviation. If any proposed candidates are accreting, their circumplanetary material must have a low dust mass, a small physical size, dust that is optically thick, or a dearth of large mm-emitting grains.
ER -