Jets in common envelopes: a low-mass main-sequence star in a red giant

ABSTRACT We present small-scale 3D hydrodynamical simulations of the evolution a 0.3 M⊙ main-sequence (MS) star that launches two perpendicular jets within envelope 0.88 red giant (RG). Based on previous large-scale simulations, we study dynamics either when secondary is grazing, it has plunged-in, or well RG (in each stage for ∼11 d). The through common (CE) depend conditions environment as their powering. In grazing and commencement plunge self-regulated need higher efficiencies to break out RG. Deep inside CE, time-scales simulated, are choked independently whether they constantly powered. Jets able in our simulations. accreted angular momentum not large enough form disc. mass accretion MS 1–10 per cent Bondi–Hoyle–Littleton rate (∼10−3–10−1 yr−1). High-luminosity emission, from X-rays ultraviolet optical, expected if CE. Our illustrate inclusion more realistic jet models dynamical CEs.