Interstellar grain mantles

Technical Report · Sat Dec 01 04:00:00 EST 1984

OSTI ID:5605520

Tielens, A; Witteborn, F; Goebel, J; Bregman, J; Allamandola, L; Dhendecourt, L B

Techniques for determining the composition of small dust grains in interstellar matter are discussed. The best way to study the composition of interstellar grain mantles is by infrared spectroscopy. The absorption features in a complete infrared spectrum from 2 to 15 microns can be used as fingerprints to identify the absorbing molecule. Ground-based observations around 3 microns confirmed the presence of H2O ice in interstellar grain mantles, through the detection of the 3.08 micron OH stretching vibration. The detection of other molecules, in particular the carbon bearing molecules, is however hampered by atmospheric absorption in the 5-8 micron region and the presence of the strong ice and silicate bands, which dominate the 3 and 10 micron region respectively. Kuiper Airborne Observatory observations of the 5-8 micron region of the spectrum are therefore extremely important to determine the composition of interstellar grain mantles. The 5 to 8 micron spectra of molecular cloud sources was obtained using a 24 detector grating spectrometer. An important characteristic of this spectrometer is that the whole spectrum is obtained simultaneously. It is therefore relatively easy to correct for atmospheric transmission.

• Research Organization: National Aeronautics and Space Administration, Moffett Field, CA (USA). Ames Research Center
• OSTI ID: 5605520
• Report Number(s): N-85-17874
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CARBON
CHEMICAL COMPOSITION
CHEMISTRY
COSMIC DUST
COSMOCHEMISTRY
DUSTS
ELEMENTS
HYDROGEN COMPOUNDS
INFRARED SPECTRA
INTERSTELLAR GRAINS
NONMETALS
OXYGEN COMPOUNDS
PARTICLES
SPECTRA
WATER