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arXiv · 0711.3055

Variation of Galactic Bar Length with Amplitude and Density as Evidence for Bar Growth over a Hubble Time

Bruce G. Elmegreen·Debra Meloy Elmegreen·Johan H. Knapen·Ronald J. Buta·David L. Block·Ivanio Puerari
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Abstract

K_s-band images of 20 barred galaxies show an increase in the peak amplitude of the normalized m=2 Fourier component with the R_25-normalized radius at this peak. This implies that longer bars have higher $m=2$ amplitudes. The long bars also correlate with an increased density in the central parts of the disks, as measured by the luminosity inside 0.25R_25 divided by the cube of this radius in kpc. Because denser galaxies evolve faster, these correlations suggest that bars grow in length and amplitude over a Hubble time with the fastest evolution occurring in the densest galaxies. All but three of the sample have early-type flat bars; there is no clear correlation between the correlated quantities and the Hubble type.

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Bruce G. Elmegreen, Debra Meloy Elmegreen, Johan H. Knapen, Ronald J. Buta, David L. Block, Ivanio Puerari. 2007-11-20. Variation of Galactic Bar Length with Amplitude and Density as Evidence for Bar Growth over a Hubble Time. https://doi.org/10.1086/524359

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