we propose to observe bright massive b[e] supergiants in the lmc and smc in order to study their circumstellar environment. this environment is very complex, with regions where gas flows out at high velocity and other regions where gas is very cool, dust is formed and the outflow velocities are low. it is suggested that b[e] stars are rapidly rotating post-main-sequence stars, but the precise nature of the stars (just evolved off the main sequence, or post-red-supergiant) is not understood. the iso observations will provide us with new insights into the mass loss and wind structure by measuring the 2-12 micron spectrum in low resolution. this will give us the line strengths of h and he emission lines, as well as several forbidden lines. in addition, we request for the brightest three stars full sws scans in order to investigate the 10-45 micron spectral region. many dust and line features can be found that are crucial for a better understanding of the evolutionary status of these stars. iso is the only instrument that will be able to provide the 10-45 micron data with a resolution of 500-1000, and the requested phot-s spectra are very difficult to obtain from the ground.
Instrument
PHT40 , SWS01
Temporal Coverage
1996-03-11T13:21:05Z/1997-08-05T13:37:55Z
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.
