2022MNRAS.514.3212H

We conduct three-dimensional hydrodynamical simulations of common envelope jets supernova (CEJSN) events where we assume that a neutron star (NS) launches jets as it orbits inside the outer zones of a red supergiant (RSG) envelope, and find the negative jet feedback coefficient to be ≃ 0.1-0.2. This coefficient is the factor by which the jets reduce the mass accretion rate on to the NS as they remove mass from the envelope and inflate bubbles (cocoons). Our results suggest that in most CEJSN events the NS-RSG binary system experiences the grazing envelope evolution before it enters a full common envelope evolution (CEE). We also find that the jets induce upward and downward flows in the RSG envelope. These flows together with the strong convection of RSG stars might imply that energy transport by convection in CEJSNe is very important. Because of limited numerical resources we do not include in the simulations the gravity of the NS, nor the accretion process, nor the jets launching process, and nor the gravity of the deformed envelope. Future numerical simulations of CEE with a NS/BH companion should include the accretion process on to the NS (and vary the jets' power accordingly), the full gravitational interaction of the NS with the RSG, and energy transport by the strong convection.