**Volume Title** ASP Conference Series, Vol. **Volume Number** **Author** c  **Copyright Year** Astronomical Society of the Pacific Population synthesis of post-common envelope white dwarf-main sequence binaries in the Sloan Digital Sky Survey Santiago Torres 1,2 , Judit Camacho 1,2 , Alberto Rebassa-Mansergas 3 ,M´ onica Zorotovic 4,5 , Matthias. R. Schreiber 3 , & Enrique Garc´ ıa–Berro 1,2 1 Departament de F´ ısica Aplicada, Universitat Polit` ecnica de Catalunya, c/Esteve Terrades 5, 08860 Castelldefels, Spain 2 Institute for Space Studies of Catalonia, c/Gran Capit` a 2–4, Edif. Nexus 104, 08034 Barcelona, Spain 3 Departamento de F´ ısica y Astronom´ ıa, Universidad de Vapara´ ıso, Avda. Gran Breta˜ na 1111, Valpara´ ıso, Chile 4 Departamento de Astronom´ ıa, Universidad Pontificia Cat´ olica de Chile, Vicu˜ na Mackenna 4860, 7820436 Macul Santiago, Chile 5 European Southern Observatory, Alonso de C´ ordova 3107, Vitacura Santiago, Chile Abstract. We present preliminary results of detailed Monte Carlo simulations of the population of binary systems in the Sloan Digital Sky Survery Data Release 7 (SDSS DR7). We have used the most up-to-date stellar evolutionary models, a complete treat- ment of the Roche lobe overflow episode, as well as a full implementation of the orbital evolution of the binary system. Moreover, we included the different selection criteria and observational biases and examined the role played by the binding energy parameter and by the common envelope efficiency. Our Monte Carlo simulator correctly repro- duces the properties of the observed distribution white dwarf plus main sequence binary systems. 1. The model and results We have expanded an existing Monte Carlo code (Garc´ ıa-Berro et al. 1999, 2004) specifically designed to study the Galactic populations of single white dwarfs to deal with the population of binaries in which one of the components is a white dwarf. The masses of each of the components of the binary system were obtained using a standard initial mass function (Kroupa et al. 1993). Also, a constant star formation rate and a disk age of 10 Gyr were adopted. In addition, orbital separations were randomly drawn according to a logarithmic probability distribution (Nelemans et al. 2001). The eccen- tricities were also randomly drawn according to a thermal distribution (Heggie 1975). For each of the components of the binary system analytical fits to detailed stellar evo- lutionary tracks were used (Hurley et al. 2000). We also used a detailed prescription for evolution during the common envelope (de Kool 1990), and up-to-date white dwarf cooling tracks (Renedo et al. 2010). Tidal effects and wind mass-loss were also consid- ered. Angular momentum losses due to to magnetic braking and gravitational radiation were taken into account as well (Schreiber & G¨ ansicke 2003; Zorotovic et al. 2010). Our synthetic binary systems were distributed in the direction of the SEGUE fields 1