The Mid-Infrared Narrow-Line Baldwin Effect Revealed by Spitzer

International audienceWe present our discovery of a narrow-line Baldwin effect, an anticorrelation between the equivalent width (EW) of a line and the flux of the associated continuum, in 5-20 mum mid-infrared (mid-IR) lines from a sample of 68 active galactic nuclei (AGNs), located at zEdd), we find no strong relationship for mid-IR lines. Our study indicates that the narrow-line mid-IR Baldwin effect is quite different from the broad-line optical/UV Baldwin effect, and it is possible that the two effects are unrelated. The anticorrelations discovered open new possibilities in understanding the physics of the ionizing region and the continuum reprocessing by dust