2015/02/28 by Muhammad Akashi, Efrat Sabach, Ohad Yogev +1
Physics and Astronomy · #Astrophysics and Star Formation Studies #Gamma-ray bursts and supernovae #Stellar, planetary, and galactic studies #astro-ph.SR
paper · pdf · doi:10.1093/mnras/stv1666
Revision after referee report
arxiv created 2015/07/01 · openalex publication_date 2015/08/28 · arxiv updated 2015/09/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We suggest that clumpy dense outflowing equatorial rings around evolved giant stars, such as in supernova 1987A and the Necklace planetary nebula, are formed by bipolar jets that compress gas towards the equatorial plane. The jets are launched from an accretion disc around a stellar companion. Using the flash hydrodynamics numerical code we perform 3D numerical simulations, and show that bipolar jets expanding into a dense spherical shell can compress gas towards the equatorial plane and lead to the formation of an expanding equatorial ring. Rayleigh–Taylor instabilities in the interaction region break the ring to clumps. Under the assumption that the same ring formation mechanism operates in massive stars and in planetary nebulae, we find this mechanism to be more promising for ring formation than mass-loss through the second Lagrangian point. The jets account also for the presence of a bipolar nebula accompanying many of the rings.