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The sigma_c-V_c correlation in high and low surface brightness galaxies

A. Pizzella·E. Dalla Bonta'·E. M. Corsini·L. Coccato·F. Bertola
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Abstract

We investigate the relation between the central velocity dispersion, sigma_0, and the circular velocity, V_c, in galaxies. In addition to previously available data, we consider an observationally homogeneus sample of 52 high surface brightness and 11 low surface brightness spiral galaxies. We performed a straight line regression analysis in a linear scale, finding a good fit, also for low sigma_0 galaxies, always rejected in the previous studies. Low surface brightness galaxies seem to behave differently, showing either higher values of V_c or lower values of sigma_0 with respect to their high surface brightness counterparts.

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A. Pizzella, E. Dalla Bonta', E. M. Corsini, L. Coccato, F. Bertola. 2003-11-03. The sigma_c-V_c correlation in high and low surface brightness galaxies. https://arxiv.org/abs/astro-ph/0311023

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