we propose to observe the c+ 158-micron line emission in order to trace the phase transitions of c in the translucent cloud g236+39 (spring launch) or the edges of the dark cloud l183 (autumn launch). g236+39 has been shown to contain the phase transitions from h/h2 and c+/co, and we will propose to observe the ci 609-micron line for comparison to the iso observations. l183 has already be observed in ci line. both g236+39 and l183 have been observed in co and its 13co isotopomer. the c+ observations will be combined with ci observations in order to distinguish the c+/ci and ci/co transitions, which must lie between the cloud edge and the co cores. these phase transitions are a key both to the cloud thermodynamics (governed by the cooling through the c+ line) and the cloud chemistry of c-bearing species (governed by the abundance of c+).
Instrument
LWS01 , LWS02
Temporal Coverage
1997-02-05T19:17:10Z/1997-09-10T20:38:50Z
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.
