ALMA survey of Lupus class III stars: Early planetesimal belt formation and rapid disc dispersal
Accepted version
Peer-reviewed
Repository URI
Repository DOI
Change log
Authors
Abstract
jats:titleABSTRACT</jats:title>
jats:pClass III stars are those in star forming regions without large non-photospheric infrared emission, suggesting recent dispersal of their protoplanetary discs. We observed 30 class III stars in the 1–3 Myr Lupus region with ALMA at ∼856μm, resulting in four detections that we attribute to circumstellar dust. Inferred dust masses are 0.036–0.093M⊕, ∼1 order of magnitude lower than any previous measurements; one disc is resolved with radius ∼80 au. Two class II sources in the field of view were also detected, and 11 other sources, consistent with sub-mm galaxy number counts. Stacking non-detections yields a marginal detection with mean dust mass ∼0.0048M⊕. We searched for gas emission from the CO J = 3–2 line, and present its detection to NO Lup inferring a gas mass (4.9 ± 1.1) × 10−5 M⊕ and gas-to-dust ratio 1.0 ± 0.4. Combining our survey with class II sources shows a gap in the disc mass distribution from 0.09–2M⊕ for
Description
Keywords
Journal Title
Conference Name
Journal ISSN
1365-2966
Volume Title
Publisher
Publisher DOI
Rights
Sponsorship
European Commission Horizon 2020 (H2020) Marie Sk?odowska-Curie actions (823823)
Science and Technology Facilities Council (ST/N000927/1)