Dust penetrated arm classes: insight from rising and falling rotation curves

Marc S. Seigar; David L. Block; Ivanio Puerari

doi:10.1007/978-1-4020-2862-5_12

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Dust penetrated arm classes: insight from rising and falling rotation curves

Marc S. Seigar·David L. Block·Ivanio Puerari

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Abstract

We present near-infrared K-band images of 15 galaxies. We have performed a Fourier analysis on the spiral structure of these galaxies in order to determine their pitch angles and dust-penetrated arm classes. We have also obtained rotation curve data for these galaxies and calculated their shear rates. We show that there is a correlation between pitch angle and shear rate and conclude that the main determinant of pitch angle is the mass distribution within the galaxy. This correlation provides a physical basis for the dust-penetrated classification scheme of Block & Puerari (1999).

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Marc S. Seigar, David L. Block, Ivanio Puerari. 2004-06-22. Dust penetrated arm classes: insight from rising and falling rotation curves. https://doi.org/10.1007/978-1-4020-2862-5_12

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