The spin rates and spin evolution of the O components in WR+O binaries

Understand

Despite 50 years of extensive binary research we have to conclude that the Roche lobe overflow/mass transfer process that governs close binary evolution is still poorly understood.

• It is the scope of the present paper to lift a tip of the veil by studying the spin-up and spin-down processes of the O-type components of WR+O binaries.
• We critically analyze the available observational data of rotation speeds of the O-type components in WR+O binaries.
• By combining a binary evolutionary code and a formalism that describes the effects of tides in massive stars with an envelope in radiative equilibrium, we compute the corresponding rotational velocities during the Roche lobe overflow of the progenitor binaries.