ISOCAM MOLECULAR-HYDROGEN IMAGES OF THE CEPHEUS-E OUTFLOW

The physical characteristics of the Cepheus E ''embedded'' outflow are analyzed using ISOCAM images in the upsilon = 0-0 S(5) 6.91 mu m and S(3) 9.66 mu m molecular hydrogen lines. We find that the morphology o f the Cep E outflow in the ground vibrational H-2 lines is similar to that in the near-infrared upsilon = 1-0 2.12 mu m line. At these mid-i nfrared wavelengths, we detect neither the second H-2 outflow that is almost perpendicular to the Cep E 2.12 mu m flow nor traces of H-2 emi ssion along the second (CO)-C-12 J = 2-1 outflow, at an angle of simil ar to 52 degrees, down to a surface brightness of 12-46 mu Jy arcsec(- 2). We do detect at 6.91 mu m the likely source of the main H-2 and CO outflows, IRAS 23011 + 6126, and show that the source is easily seen in all IRAS bands using HIRES images. The source is not detected at 9. 66 mu m, but we think this agrees with the interstellar extinction cur ve, which has a minimum at similar to 7 mu m but rises at similar to 9 .7 mu m as a result of the strong absorption silicate feature, enhance d in this case by a cocoon surrounding the Class 0 object. This idea i s supported by our models of the spectral energy distribution (SED) of the central object. The models assume that the main source of opacity is due to bare silicates, and our best fit for the SED yields a total envelope mass of 17 M. and a dust temperature of 18 K.