Collective Instabilities of Self - Gravitating Systems . III - - Disk - Halo System - - Fumio
نویسندگان
چکیده
The instability modes of the infinitesimally thin self-gravitating disk, which is composed of rotating and non-rotating parts, are investigated. By solving the dispersion relation numerically under various physical situations, two growing modes are found. They are the modified Jeans mode of rotating component or non-rotating one and the Landau mode by wave-particle (non-rotating component) interactions. Possible relevances to spiral arms are discussed briefly.
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