HR diagram for the FGK stars of the DUNES sample observed by the DEBRIS team (DUNES_DB). The colour codes following the Hipparcos spectral types are F stars (violet), G stars (green), and K stars (red). Solid circles represent FGK stars closer than 20 pc; empty triangles are FGK stars further away. The two red dots at the bottom right of the diagram are two stars classified as K5 in the Hipparcos catalogue, but their colours correspond to M stars. See text for details.