we propose to observe the interaction of x-rays from young stars in molecular clouds with the surrounding dust. for t tauri stars in the outer regions of molecular clouds, the signature of this interaction is predicted to be the disappearance of pah features within 0.01 to 0.1 pc from the star. for herbig ae/be stars, which are usually surrounded by dense circumstellar dust, the signature of x-ray interaction may be the disappearance of pah emission in the close vicinity of the star. from recent x-ray data provided by the rosat and asca satellites, we select 4 t tauri stars in the rho oph cloud (autumn launch), and 3 in the orion and taurus clouds (spring launch). we also select 6 herbig ae/be stars with a wide range of x-ray luminosities. we use the imaging properties of isocam (using 7 filters centered on pah and silicate features and their references) to study the dependence of the pah emission as a function of distance to the x-ray source. the results should constrain both our knowledge of the composition of the smallest dust grains, and of the heating of dust by hard radiation.
Instrument
CAM01 , SWS01
Temporal Coverage
1996-03-14T02:50:43Z/1996-06-24T00:28:31Z
Version
1.0
Mission Description
The Infrared Space Observatory (ISO) was the world's 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.
