Bernardo Cervantes-Sodi, Cheng Li, Changbom Park, Lixin Wang
We present a study of the connection between the galactic spin parameter $\lambda_{d}$ and the bar fraction in a volume-limited sample of 10,674 disk galaxies drawn from the Sloan Digital Sky Survey Data Release 7. The galaxies in our sample are visually classified into galaxies hosting strong or weak bars, and non-barred galaxies. We find that the spin distributions of these three classes are statistically different, with galaxies hosting strong bars with the lowest $\lambda_{d}$ values, followed by non-barred galaxies, while galaxies with weak bars present typically high spin parameters. The bar fraction presents its maximum at low to intermediate $\lambda_{d}$ values for the case of strong bars, while the maximum for weak bars is at high $\lambda_{d}$. This bi-modality is in good agreement with previous studies finding stronger bars hosted by luminous, massive, red galaxies with low content of cold gas, while weak bars are found in low luminosity, low mass, blue galaxies, usually gas rich. In addition, the rise and fall of the bar fraction within the strong-bar sample shown in our results, can be explained as a result of two competing factors, the self-gravity of the disk that enhances bar instabilities, and the support by random motions instead of ordered rotational motion, that prevents the formation/growth of bars.
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http://arxiv.org/abs/1303.3696
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