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Line-of-sight velocity distributions of low-luminosity elliptical galaxies

C. Halliday·Roger L. Davies·Harald Kuntschner·M. Birkinshaw·Ralf Bender·R. P. Saglia·Glenn Baggley
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Abstract

The shape of the line-of-sight velocity distribution (LOSVD) is measured for a sample of 14 elliptical galaxies, predominantly low-luminosity ellipticals. The sample is dominated by galaxies in the Virgo cluster but also contains ellipticals in nearby groups and low density environments. The parameterization of the LOSVD due to Gerhard and van der Marel and Franx is adopted, which measures the asymmetrical and symmetrical deviations of the LOSVD from a Gaussian by the amplitudes h3 and h4 of the Gauss-Hermite series. Rotation, velocity dispersion, h3 and h4 are determined as a function of radius for both major and minor axes. Non-Gaussian LOSVDs are found for all galaxies along the major axes. Deviations from a Gaussian LOSVD along the minor axis are of much lower amplitude if present at all. Central decreases in velocity dispersion are found for three galaxies. Two galaxies have kinematically-decoupled cores: NGC 4458 and the well-known case of NGC 3608.

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C. Halliday, Roger L. Davies, Harald Kuntschner, M. Birkinshaw, Ralf Bender, R. P. Saglia, Glenn Baggley. 2001-03-19. Line-of-sight velocity distributions of low-luminosity elliptical galaxies. https://doi.org/10.1046/j.1365-8711.2001.04492.x

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