A three-dimensional hydrodynamics simulation of oxygen-shell burning in the final evolution of a fast-rotating massive star

We perform for the first time a 3D hydrodynamics simulation of evolution last minutes pre-collapse oxygen shell fast-rotating massive star. This star has an initial mass 38 M$_\odot$, metallicity $\sim$1/50 Z$_\odot$, rotational velocity 600 km s$^{-1}$, and experiences chemically homogeneous evolution. It silicon- oxygen-rich (Si/O) convective layer at (4.7-17)$\times 10^{8}$ cm, where oxygen-shell burning takes place. The power spectrum analysis turbulent indicates dominance large-scale mode ($\ell \sim 3$), which also been seen in non-rotating stars that have wide Si/O layer. Spiral arm structures density silicon-enriched material produced by appear equatorial plane shell. Non-axisymmetric, ($m \le 3$) modes are dominant these structures. spiral not identified previous pre-supernova models. Governed such convection pattern, angle-averaged specific angular momentum becomes constant layer, is considered spherically symmetrical stellar Such arms might affect ensuing explosion or implosion