doi.eso.org

• Decin, Leen [KU Leuven, Belgium]
• Gottlieb, Carl [Center for Astrophysics | Harvard & Smithsonian, Cambridge, USA]
• Richards, Anita [Jodrell Bank Centre for Astrophysics, Manchester, UK]
• Baudry, Alain [Bordeaux University, France]
• Danilovich, Taissa [KU Leuven, Belgium]
• Cannon, Emily [KU Leuven, Belgium]
• Ceulemans, Thomas [KU Leuven, Belgium]
• De Ceuster, Frederik [KU Leuven, Belgium]
• de Koter, Alex [University of Amsterdam, the Netherlands]
• El Mellah, Ileyk [Grenoble Alpes University, Grenoble, France]
• Etoka, Sandra [University of Manchester, UK]
• Gottlieb, Elaine [Harvard University, USA]
• Gray, Malcolm [NARIT, Thailand]
• Herpin, Fabrice [Bordeaux University, France]
• Homan, Ward [ULB, Brussels, Belgium]
• Jeste, Manali [Max Planck Institute for Radio Astronomy, Bonn, Germany]
• Kervella, Pierre [LESIA, Meudon, France]
• Maes, Silke [KU Leuven, Belgium]
• Malfait, Jolien [KU Leuven, Belgium]
• Marinho, Louise [Bordeaux University, France]
• Menten, Karl [Max Planck Institute for Radio Astronomy, Bonn, Germany]
• Millar, Tom [Queen’s University Belfast, UK]
• McDonald, Iain [Open University, UK]
• Montargès, Miguel [LESIA, Meudon, France]
• Müller, Holger [University of Cologne, Germany]
• Pimpanuwat, Bannawit [University of Manchester, UK]
• Plane, John [University of Leeds, UK]
• Sahai, Ragvendra [Jet Propulsion Laboratory, USA]
• Van de Sande, Marie [University of Leeds, UK]
• Wallström, Sofia [KU Leuven, Belgium]
• Wong, Ka Tat [IRAM, Grenoble, France]
• The ATOMIUM Consortium [KU Leuven, Belgium]

The goals of the Atacama Large Millimeter/submillimeter Array (ALMA) Large Programme ATOMIUM are to obtain a quantitative understanding of the chemical and physical processes that govern the phase transition from small gaseous molecules to dust grains in the inner wind of oxygen-rich evolved stars; and to study the interplay between dynamical and chemical phenomena in the outflow of 17 asymptotic giant branch (AGB) and red supergiant (RSG) stars which span a range in (circum)stellar and wind properties — such as mass-loss rate, pulsation behaviour, and spatial structure of the wind-dominated ambient medium. The observations were made with three configurations of the ALMA array that encompass a range in angular resolution of approximately 0.02–1 arcseconds. They consist of 27-GHz-wide homogeneous spectral-line and continuum surveys in the 214–270 GHz range in each source in the sample, and provide an unambiguous comparison among sources. Equipped with these tools, we then show how the stellar winds of all the ATOMIUM sources exhibit distinct non-spherical geometries that can be explained by binary interaction and — depending on the parameters of the binary system — can produce a wide variety of morphologies as illustrated by the example of the AGB star π¹ Gru. In parallel with ATOMIUM, contemporaneous observations of all but three of the 17 sources were made in the visible with the SPHERE/ZIMPOL instrument at ESO’s Very Large Telescope (VLT). The VLT/SPHERE observations provided direct images of the dust at a spatial resolution comparable to that obtained with ALMA. Novel hydrodynamical simulations of binary systems were done so as to further the interpretation of the near simultaneous observations of the gas and dust. We also present a brief overview of the 24 molecules that were identified in the survey, followed by a discussion of how the molecules inform us about the inner wind and the (super)giant outflow, and of some future possible observations with ALMA, ESO instruments, and the JWST.