Virial models and anisotropy of velocity dispersion in E-galaxiesстатья
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 25 марта 2020 г.
Аннотация:Abstract A tensor virial approach is used to construct de- tailed models of 22 flattened ellipticals. The models are combined with the new observational data: extended sur- face brightness distributions, the profiles of isophotes flat- tening and their twisting, the rotation curves and the veloc- ity dispersion profiles. A key feature of these models is a rigorous consideration of the influence of the spatial shape of galaxies (oblate spheroid or triaxial ellipsoid) on the dy- namics, as well as the structure of the internal density layers in these systems. For each galaxy the ratio of the rotational energy to the potential energy t = T rot |W | was found. Compar- ing this ratio with the observed v rot σ it is concluded that the majority of these systems cannot have isotropic velocity dis- persion tensors. The anisotropy parameter β is limited to the interval 0.0 ≤ β ≤ 0.224. An including of the gradient M/L profile decreases this parameter by 21% for the M87 galaxy. A correlation was found between β and flattening of the outer regions for giant E-galaxies. Our results are com- pared with the results of other researchers. It was found that for small fast rotators our values β are in good agreement with those, obtained in the ATLAS 3D project. However, for giant E-galaxies, our models provide better agreement with observations, than axisymmetric JAM models. In addition, our velocity dispersion anisotropy results are in satisfactory agreement with the results of high resolution cosmological simulations in the Illustris project.