Detection of Keplerian dynamics in a disk around the post-AGB star AC Her

Abstract

So far, only one rotating disk has been clearly identified and studied in AGB or post-AGB objects (in the Red Rectangle), by means of observations with high spectral and spatial resolution. However, disks are thought to play a key role in the late stellar evolution and are suspected to surround many evolved stars. We aim to extend our knowledge on these structures. We present interferometric observations of CO J=2-1 emission from the nebula surrounding the post-AGB star AC Her, a source belonging to a class of objects that share properties with the Red Rectangle and show hints of Keplerian disks. We clearly detect the Keplerian dynamics of a second disk orbiting an evolved star. Its main properties (size, temperature, central mass) are derived from direct interpretation of the data and model fitting. With this we confirm that there are disks orbiting the stars of this relatively wide class of post-AGB objects

4 pages, 3 figures

References in corpus (5)

• Millimeter imaging of HD 163296: probing the disk structure and kinematics
• The nebula around the post-AGB star 89 Her
• Minkowski's Footprint revisited. Planetary Nebula formation from a single sudden event?
• Two short mass-loss events that unveil the binary heart of Minkowski's Butterfly Nebula
• Gomez's Hamburger (IRAS 18059-3211): A pre main-sequence A-type star

Cited by in corpus (26)

• (Sub)stellar companions shape the winds of evolved stars
• Testing eccentricity pumping mechanisms to model eccentric long period sdB binaries with MESA
• Further ALMA observations and detailed modeling of the Red Rectangle
• Establishing binarity amongst Galactic RV Tauri stars with a disc
• A mid-IR interferometric survey with MIDI/VLTI: resolving the second-generation protoplanetary disks around post-AGB binaries
• A second post-AGB nebula that contains gas in rotation and in expansion: ALMA maps of IW Car
• The evolved circumbinary disk of AC Her: a radiative transfer, interferometric and mineralogical study
• ALMA high spatial resolution observations of the dense molecular region of NGC 6302
• Keplerian disks and outflows in post-AGB stars: AC Herculis, 89 Herculis, IRAS 19125+0343, and R Scuti
• Where Are the Binaries? Results of a Long-Term Search for Radial Velocity Binaries in Proto-Planetary Nebulae
• The ALMA detection of CO rotational line emission in AGB stars in the Large Magellanic Cloud
• Resolved imaging of the AR Puppis circumbinary disk
• Discovery of a Metal-poor, Luminous Post-AGB Star that Failed the Third Dredge-up
• Transition disc nature of post-AGB binary systems confirmed by mid-infrared interferometry
• What does a typical full-disc around a post-AGB binary look like? -- Radiative transfer models reproducing PIONIER, GRAVITY, and MATISSE data
• A detailed view on the circumstellar environment of the M-type AGB star EP Aquarii I. High-resolution ALMA and SPHERE observations
• Chemistry of nebulae around binary post-AGB stars: A molecular survey of mm-wave lines
• Multi-wavelength VLTI study of the puffed-up inner rim of a circumbinary disc
• Second-generation protoplanetary discs around evolved binaries: a high-resolution polarimetric view with SPHERE/IRDIS
• Dissecting the central regions of OH 231.8 + 4.2 with ALMA: a salty rotating disk at the base of a young bipolar outflow
• Three-dimensional orbit of AC Her determined: Binary-induced truncation cannot explain the large cavity in this post-AGB transition disk
• Magnetically driven winds from accretion disks in post-asymptotic giant branch binaries
• A SOFIA FORCAST Grism Study of the Mineralogy of Dust in the Winds of Proto-planetary Nebulae: RV Tauri Stars and SRd Variables
• Jet formation in post-AGB binaries: Confronting cold magnetohydrodynamic disc wind wind models with observations
• Modelling the impact of circumbinary disk accretion on post-AGB binary evolution and surface chemistry
• SPHERE/ZIMPOL insights into discs around evolved stars: arcs, asymmetries and dust properties