we propose to do low resolution spectroscopy with isocam and the sws of two very distant iras galaxies in order to search for dust features in their infrared spectrum, and to measure their continuum ir emission. the near and mid infrared domain is well suited since well known spectral features due to dust grains appear either in absorption: the silicate band at 9.8 microns and the ice band at 13.3 microns, or in emission: the uir bands at 3.3, 6.2, 7.7, 8.6 and 11.3 microns. we shall also measure the overall continuum spectrum, a very important ingredient in the interpretation of faint galaxy counts and in the prediction of the extragalactic background in the infrared. due to the high redshift of the targets, the wavelength of the dust features is shifted in the mid infrared where iso is most sensitive. such observations are of utmost importance for the understanding of the formation of galaxies. moreover, the dust is an ubiquitous component of the interstellar medium which properties are still poorly known. these new observations in conditions very different from the galactic molecular clouds will help to understand the mechanism of formation and the nature of the dust.
Instrument
CAM04 , PHT03
Temporal Coverage
1996-12-27T12:35:09Z/1996-12-27T21:54:33Z
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.
