... Tsuchiya

Present address: SGI Japan Ltd., Ebisu Garden Place Tower 31F, 4-20-3 Ebisu, Shibuya-ku, Tokyo 150-6031, Japan.

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... disk

It can be shown (Toomre & Kalnajs 1980, unpublished results; Sellwood & Kahn 1991; Fuchs 2005) that even the shearing sheet develops rigidly propagating, exponentially growing spiral modes, if a sharp left hand boundary is introduced.

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