Jet-powered turbulence in common envelope evolution

TL;DR

This study uses 3D hydrodynamical simulations to explore how jets launched by a neutron star during common envelope evolution influence turbulence, angular momentum transfer, and potential observable phenomena like CEJSN events.

Contribution

It demonstrates that jets can induce turbulence, transfer angular momentum, and shape the envelope in CEE, highlighting their significant role in the evolution and observable outcomes.

Findings

Jets create vortices and inflate low-density bubbles.

Jets deposit angular momentum comparable to orbital angular momentum.

Turbulence from jets may cause bumps in light curves of CEJSN events.

Abstract

We conduct a three-dimensional hydrodynamical simulation of a common envelope evolution (CEE) where a neutron star (NS) spirals-in inside the envelope of a red supergiant (RSG) star in a predetermined orbit. We find that the jets shed pairs of vortices in an expanding spiral pattern, inflate two expanding spirally-shaped low-density bubbles, one above and one below the equatorial plane, and deposit angular momentum to the envelope. In the simulation we do not include the gravity of the NS such that all effects we find are solely due to the jets that the spiralling-in NS launches. The angular momentum that the jets deposit to the envelope is of the same order of magnitude as the orbital angular momentum and has the same direction. The turbulence that the jets induce in the common envelope might play a role in transporting energy and angular momentum. The jet-deposited energy that is radiated away (a process not studied here) leads to a transient event that is termed common envelope jets supernova (CEJSN) and might mimic an energetic core collapse supernova. The turbulence and the spiral pattern that we explore here might lead to bumps in the late light curve of the CEJSN when different segments of the ejected envelope collide with each other. This study emphasizes the roles that jets can play in CEE (including jets launched by black hole companions) and adds to the rich variety of processes in CEJSN events.