Videos

Common-envelope simulations including different sources of recombination energy

These videos are associated with the publication Common envelopes in massive stars II: The distinct roles of hydrogen and helium recombination (Lau et al., 2022b). Data accompanying our publication is available here.


For each simulation, we show the density cross-section in the equatorial/orbital plane, in the meridional plane, and in a meridional plane instantaneously co-rotating with the stellar cores.



Type of recombination  
H + He + H2 Equatorial   Meridional
He + H Equatorial   Meridional
He Equatorial   Meridional
None Equatorial   Meridional
None, fixed μ See the gas + radiation equation of state simulation in Paper I


H + He + H2 recombination energy

These simulations include energy from recombination into H, He and H2. This is similar to past 3D hydrodynamical simulations that have included recombination energy through using the MESA or OPAL equation of state tables.

H + He + H2 (equatorial plane).

H + He + H2 (meridional plane).


H + He recombination energy

These simulations include energy released during H and He atomic recombination.

H + He (equatorial plane).

H + He (meridional plane).


He recombination energy

These simulations include only He recombination energy.

He (equatorial plane).

He (meridional plane).


No recombination energy

These simulations do not include any recombination energy, but model the effect of increased mean molecular weight, μ, associated with recombination.

No recombination energy (equatorial plane).

No recombination energy (meridional plane).


No recombination energy, fixed μ

This is the case where no recombination energy is included, and the mean molecular weight is held fixed at μ = 0.62, corresponding to a fully ionised convective envelope. This case is identical to the gas + radiation equation of state simulation in Paper I (Lau et al., 2022)—its movies are shown on here.