Preparing the next gravitational million-body simulations: Evolution of single and binary stars in Nbody6++GPU, MOCCA and McLuster

Understand

We present the implementation of updated stellar evolution recipes in the codes \texttt{Nbody6++GPU, MOCCA} and \texttt{McLuster}.

• We test them through numerical simulations of star clusters containing $1.1\times 10^5$ stars (with $2.0\times 10^4$ in primordial hard binaries) performing high-resolution direct $N$-body (\texttt{Nbody6++GPU}) and Monte-Carlo (\texttt{MOCCA}) simulations to an age of 10~Gyr.
• We compare models implementing either delayed or core-collapse supernovae mechanisms, a different mass ratio distribution for binaries, and white dwarf natal kicks enabled/disabled.
• Compared to \texttt{Nbody6++GPU}, the \texttt{MOCCA} models appear to be denser, with a larger scatter in the remnant masses, and a lower binary fraction on average.