due to large obscuration, the outflow activity of the youngest low-mass stars remains poorly understood. recent ground-based near-infrared imaging of outflows from embedded ysos has opened a promising obser- -vational approach using h2 lines which trace radiative shocks. these new observations suggest that the fast, highly collimated co outflows emanating from the youngest (class 0) protostars are driven by jets fairly similar to the optical jets observed around some unobscured pre-main sequence stars. a unified model is now emerging, according to which all co outflows represent ambient gas that has been entrained by an underlying fast jet. however, most low-mass embedded ysos have much weaker co outflow activity than class 0 protostars, and we lack a direct confirmation of the existence of the jet in these cases. isocam provides a unique opportunity to image with a good resolution and sensitivity some of the major cooling lines of low-velocity radiative shocks. we thus propose to use isocam to extend the ground- based to extend the ground-based investigations of the 2.2 micron h2 line to mid-ir h2 lines of lower excitation levels which will probe lower velocity shocks and will be much less sensitive to extinction from the ambient cloud. the target fields we have selected have all been observed by us with the vla in the radio continuum, and are covered by the central programme survey for ysos (nordh et al.). by combining all these observations, we hope to reach statistically significant conclusions about the nature and frequency of occurrence of jets in young stellar populations.
Instrument
CAM01
Temporal Coverage
1996-09-22T22:03:46Z/1997-02-14T22:16:18Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the worlds first true orbiting infrared observatory. Equipped with four highly-sophisticated and versatile scientific instruments, it was launched by Ariane in November 1995 and provided astronomers world-wide with a facility of unprecedented sensitivity and capabilities for a detailed exploration of the Universe at infrared wavelengths.
European Space Agency, BONTEMPS et al., 1999, 'MID-IR SEARCH FOR EMBEDDED OUTFLOW SHOCKS AROUND YSOS', 1.0, European Space Agency, https://doi.org/10.5270/esa-n4gd2xw
