A. Abergel, J.P. Bernard , F. Boulanger, C. Cesarsky, F.X. Désert, E. Falgarone, G. Lagache, M. Perault, J.-L. Puget, W.T. Reach, L. Nordh, G. Olofsson 3, M. Huldtgren, A.A. Kaas , P. André, S. Bontemps, M. Burgdorf, E. Copet, J. Davies , T. Montmerle, P. Persi, F. Sibille
We present preliminary results of the ISOCAM survey of the Ophiuchi main cloud L1688 (0.5 square degrees) conducted in the two broad-band filters LW2 (5-8.5 m) and LW3 (12-18 m). This letter focuses on the properties of the extended emission. The high angular resolution and sensitivity of the ISOCAM observations have revealed several previously unknown characteristics of the mid-IR diffuse emission: the small scale filamentary structure (thickness 0.03 pc) of the emission at the illuminated edge of the molecular cloud, the sharpness of color variations at cloud edges, the barely resolved filamentary structure of the dust emission surrounding a bright embedded source, and several dense cores seen as sharp and deep absorption structures against the diffuse cloud background.
Keywords:
- ISM: individual objects: Ophiuchus
- ISM: dust, extinction - ISM: clouds - Infrared: ISM: clouds