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