‘maximum ’ disks
نویسنده
چکیده
Decompositions of the rotation curves of NGC 2613, 3198, 6503, and 7184 are analyzed. For these galaxies the radial velocity dispersions of the stars have been measured and their morphology is clearly discernible. If the parameters of the decompositions are chosen according to the 'maximum' disk hypothesis, the Toomre Q stability parameter is sytematically less than one and the multiplicities of the spiral arms as expected from density wave theory are inconsistent with the observed morphologies of the galaxies. The apparent Q <1 instability, in particular, is a strong argument against the 'maximum' disk hypothesis.
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تاریخ انتشار 1998