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

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

We investigate the relation between the asymptotic circular velocity, V_c, and the central stellar velocity dispersion, sigma_c, in galaxies. We consider a new sample of high surface brightness spiral galaxies (HSB), low surface brightness spiral galaxies (LSB), and elliptical galaxies with HI-based V_c measurements. We find that: 1) elliptical galaxies with HI measurements fit well within the relation; 2) a linear law can reproduce the data as well as a power law (used in previous works) even for galaxies with sigma_c < 70 km/s; 3) LSB galaxies, considered for the first time with this respect, seem to behave differently, showing either larger V_c values or smaller sigma_c values.

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A. Pizzella, E. Dalla Bonta`, E. M. Corsini, L. Coccato, M. Sarzi, F. Bertola. 2004-04-14. The V_c-sigma_c relation in high and low surface brightness galaxies. https://doi.org/10.1017/s1743921304002029

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