Discovery of Seven Companions to Intermediate Mass Stars with Extreme Mass Ratios in the Scorpius-Centaurus Association
Kraus, Adam L.
Ireland, Michael J.
Carpenter, John M.
Astrophysical Journal Letters
American Astronomical Society / IoP Publishing
We report the detection of seven low-mass companions to intermediate-mass stars (SpT B/A/F; M ∼ 1.5–4.5Me) in the Scorpius–Centaurus (Sco–Cen) Association using nonredundant aperture masking interferometry. Ournewly detected objects have contrasts ΔL′ ≈ 4–6, corresponding to masses as low as ∼20 MJup and mass ratios of q ≈ 0.01–0.08, depending on the assumed age of the target stars. With projected separations ρ ≈ 10–30 AU, our aperture masking detections sample an orbital region previously unprobed by conventional adaptive optics imaging of intermediate-mass Sco–Cen stars covering much larger orbital radii (∼30–3000 AU). At such orbital separations, these objects resemble higher-mass versions of the directly imaged planetary mass companions to the 10–30 Myr, intermediate-mass stars HR 8799, β Pictoris, and HD 95086. These newly discovered companions span the brown dwarf desert, and their masses and orbital radii provide a new constraint on models of the formation of low-mass stellar and substellar companions to intermediate-mass stars.
NASA - Sagan Fellowship Program
NASA - Hubble Fellowship grant
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Vol. 806 (1), article L9
Hubble Fellowship grant 51257.01 awarded by the STScI, which is operated by AURA, Inc., for NASA, under contract NAS 5-26555