| Description |
We propose to observe a sample of nine very red protostars serendipitously
identified in PACS observations for the Herschel Orion Protostar Survey (HOPS).
In contrast to the known Orion protostars targeted in HOPS, the new sources
are undetected or very faint in Spitzer 24 micron imaging of Orion. They are
redder than the known Orion Class 0 protostars, and appear similar to the
most extreme Class 0 objects known. These objects are likely to
be in a very early and short lived stage of protostellar evolution.
With this sample, we aim to determine if the youngest protostars
begin their lives in a violent energetic phase or in a more quiescent manner,
slowly building their accretion and outflow power. To do this, we propose
PACS Range Spectroscopy between 70 and 200 microns, observing the
CO and H2O lines, and line spectroscopy centered on the 63 micron
[OI] line. These far-IR cooling lines are powerful diagnostics of
shock heating by outflows and radiant UV heating from accretion
luminosity. Through a comparison with existing HOPS observations,
these observations will be a unique window on the early evolution
of outflows and accretion in protostars. |
