Mode linewidths (normalized by the solar value, Γ_sun = 0.95   μHz) versus effective temperature. The squared symbols represent theoretical calculations computed as explained in Sects. 2.1 and 2.2. The triangles correspond to the observations of main-sequence stars derived by Appourchaux et al. (2012) from the Kepler data (with their 3-σ error-bars). The dots correspond to the observations of red giants (with T_eff < 5200 K) and main-sequence (with T_eff > 5200 K, with their 3-σ error-bars) stars as derived by Baudin et al. (2011) from the CoRoT data.