Formation of Close Double White Dwarfs: model results VS observation

We do a binary population synthesis (BPS) simulation about the close double white dwarfs (CDWDs), two main BPS modifications are as follows.

1.The mass–orbital period relation after stable RLOF is implemented into our BPS code;

2.The mass transfer stability criterionis obtained from adiabatic mass loss model(Ge, H et al. 2015).