Thermal properties of Small Grains with Fluctuating Temperature under Diffuse Interstellar Radiation Field.
Temperature history of very small interstellar dust particles is followed under diffuse interstellar radiation. Because of extremely small thermal capacities of these grains with sizes ranging from a few tens to hundred Angstroms in radii, they are to experience strong fluctuations in temperature whenever they are hit by interstellar ultraviolet photons. Fluctuating temperature can inhibit these smaller component of interstellar dust from growing into core-mantle particles of submicron sizes by continuosly evaporating atoms and molecules absorbed on their surface. This is interpreted as a possible physical reason for the bimodal nature in grain size distribution. A brief discussion is also given to the far infrared emission properties of such small grains in diffuse interstellar dust clouds.
Journal of Korean Astronomical Society
- Pub Date:
- December 1979
- GRAIN TEMPERATURE;
- TEMPERATURE FLUCTUATION;
- EVAPORATION RATE;
- FAR IR EMISSION