Mass Function at the end of the Main Sequence: the M35 Open Cluster

We present very deep RIc photometry of the M35 open cluster. We have covered 30' \times 30', equivalent to about a fourth of the total area of the cluster. The data range from I_c=17.5 to 23.5 magnitudes, and the color interval is $0.5 \le (R-I)_c \le 2.5$. Roughly, these values correspond from $0.6 M_\odot$ to $0.1 M_\odot$ in the cases of members of the cluster. By using the location of the stars on a Color-Magnitude Diagram, we have selected possible members of this cluster and obtained the Luminosity and Mass Functions of the M35 open cluster and compared them with those from the Pleiades.