Contents of: VI/111/./abstract/JCERNICH_DUSTJETS.abs

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HH  jets  and  molecular  outflows represent probably different aspects of the
same  physical  phenomena  :  the formation of stars and their first stages of
evolution.  This  conexion  between  HH  jets  and molecular outflows has been
strongly  confirmed  recently by Cernicharo and Reipurth (1996) in HH111 where
they  have  found  extremely  high velocity CO bullets just and the end of the
optical jet, i.e. the jet appears to coexist with previous ejections of matter
from  the  newly  formed  star  similar  to  that found in class 0 sources. In
proposal HH_jets we have obtained a CVF of HH1-2 and images of HH111. In HH1-2
we have detected the exciting source of the optical jet and we have discovered
a dust counterpart to this jet. Figure 1 shows a ISOCAM map taken with the LW2
filter  and pixel size of 6" of the HH1-2 region. The central source (which is
not  visible  in the near infrared) appears very prominently (see Figure 2 and
3).  Running  Northwest  of  this  source  we  have  found collimated emission
coinciding  in  position  and  size  with  the molecular emission of H2 in its
ro-vibrational  band  at  2  um.  The  emission over the jet (see Figure 3) is
featureless  which  means  that  we  are observing emission from warm dust. It
appears  very  strong  6  arcsec North of the star with a completely different
spectrum.  The  enhancement  of the emission can be seen in several positions.
The  exciting  source  exhibits  a spectrum typical of a deeply embedded young
star  (see Figures 2 and 3). Absorption features due to silicates, H2O (6 um),
CO2 (15 um) and the unknown 6.7 um band are easily identified. The CO2 feature
is so strong that it can observed at several positions. There is no doubt that
we are observing the cocoon around the central star.
In  the direction of the HH2 object we have found two different kind of shocks
(see Figure 4): a dissociative shock showing only strong NeII emission and one
no-dissociative  shock  exhibiting  all  the pure rotational lines of H2 from
S(2) to S(8). The proposed follow up will constitute an important input to the
study  of  the  formation  of  young  stars,  the physical properties of their
circumstellar disk and the temperature of the dust jet.


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