This proposal is to observe the energy sources of molecular outflows,
to try and understand the physical properties of the stars at this
stage in their evolution. Most, and perhaps all stars, undergo a period
of intense outpouring of material early on in their lives. Some are
observed to eject optical jets, while others eject molecular outflows.
Indeed, it is believed that jets and molecular outflows are different
aspects of the same phenomenon. The energy sources for optical jets
are to be investigated in the guaranteed proposal BREIPURT_HHSOURCE. It
is important, therefore, to perform a similar investigation of the
energy sources for molecular outflows. What makes them different to
the sources of optical jets? What are the time scales for this phase
in a star's evolution?
It is intended that ISOPHOT will be
used to determine an accurate spectral energy distribution (SED)
of each of the sources, using the same filters as for
BREIPURT_HHSOURCE, but with the addition of a silicate feature
filter. These data, combined with ground based near-IR
and millimetre data and IRAS data, will provide a detailed picture
of the powerhouse for molecular outflows.