iras16293-2422 is one of the youngest and best studied sources so far known (e.g. ceccarelli et al. 1997). the source is actually a binary system, whose components are both very cold and young objects, belonging to the so called class 0 (andre., ward-thompson & barsony 1993).both objects show well developed outflows almost perpendicurarly oriented, that have been observed in the co low-js transitions (walker et al. 1988; mizuno et al. 1990) and mapped in the oi(63um) line by kao (ceccarelli et al. 1997). the lws grating spectrum we obtained in february shows unequivocally the presence of two shocks responsible for the oi(63um) and a few intermediate-js co emission lines respectively (ceccarelli et al. in preparation). the oi(63um) line testifies for a high velocity, j-type shock originated when the stellar wind impacts the surrounding static medium, whereas the co lines probe the presence of a lower velocity, c-type shock caused by the wind that pushes forward the shocked material. we propose to obtain a sws low resolution spectrum, with the goal to observe the ir h recombination lines and pure rotational h2 lines, predicted by model computations (normalized with the lws observed fluxes) to be detectable in the sws01 mode. the observation of the h2 lines, together with the observed co lines in lws, will allow us to model the low velocity shock component deriving the (low velocity shocked) gas density and temperature and ultimately the preshock conditions of the gas. we also propose to observe neii(12.8um), siii(34.8um) and feii(26.0um) lines. the ir h recombination, oi(63um) and proposed ionic line fluxes will give us the opportunity to study the high velocity shock component, enabling us to estimate the (high velocity shocked) gas density and temperature and the preshock parameters, i.e. the density and temperature in the wind, and ultimately the rate of mass loss. we also propose to obtain high resolution measurementes of the oi(63um) and co 16->15 lines on-source to have the direct measure of the two shock velocities. finally, in order to study the morphology of the shocks, we propose to obtain the lws grating spectrum toward a 3x2 map overlapping the outflow; as a follow up the oi total flux will give us the mass loss rate from the central objects.
Instrument
LWS01 , LWS04 , SWS02
Temporal Coverage
1997-03-22T15:41:35Z/1997-08-09T07:07:09Z
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, CECCARELLI et al., 1998, 'MAP OF C AND J TYPE SHOCKS IN IRAS16293-2422', 1.0, European Space Agency, https://doi.org/10.5270/esa-skx1bsf