EXTENDED MIDINFRARED EMISSION AROUND HERBIG AE BE STARS/

We have observed 7 young intermediate mass stars in the mid-infrared w ith two diaphragms of different sizes in order to detect extended emis sion. The mid-infrared part of the spectral energy distribution of HD 97048, HD 97300, and HD 176386 is dominated by extended emission. The extended mid-infrared emission can best be explained with emission fro m large molecules and small grains in a dust shell with a large inner cavity devoid of small particles. The 4 strong midinfrared sources of our sample (T CrA, R CrA, HD 104237 and IRAS 12496-7650) are dominated by emission within the smallest diaphragm (5.4'') used in this work. When extended emission around Herbig Ae/Be stars is present, it contri butes significantly to the mid-infrared luminosity and must be taken i nto account both in future observational and theoretical studies.