The temperature of non - spherical interstellar grains
نویسندگان
چکیده
A model of spheroidal particles is used to calculate the steady-state temperature of dust grains immersed in the interstellar radiation field. It is found that the temperature of non-spherical grains with the aspect ratios a/b < ∼ 2 deviates from that of spheres less than 10 %. More elongated or flattened particles are usually cooler than spheres of the same mass and in some cases the temperatures may differ by even about a factor of 2. The shape effects increase with the infrared absorptivity of the grain material and seem to be more important in dark interstellar clouds.
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