2007/12/14 by Ewa L. Lokas, Ewa L. Łokas, Jarosław Klimentowski +6 · 1 citation
Physics and Astronomy · #Adaptive optics and wavefront sensing #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.0712.2372
7 pages, 5 figures, contribution to the proceedings of XIX Rencontres de Blois
arxiv created 2007/12/14 · openalex publication_date 2007/12/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We discuss how different approaches to selecting member stars in kinematic samples of dwarf spheroidal galaxies affect the estimates of their mass and anisotropy of stellar orbits. We demonstrate that the selection of members is an additional source of error compared to the usual uncertainties due to the sampling of velocity moments. As an example we use the kinematic data set for 202 stars in the Fornax dwarf galaxy for which we model the velocity dispersion profile and estimate the mass-to-light ratio and anisotropy assuming that mass follows light. We also show that stronger constraints on these parameters can be obtained if kurtosis of the velocity distribution is included in the analysis. Using the Besancon model of the Milky Way we demonstrate that the majority of contamination in Fornax probably comes from the Milky Way stars.