Astrophysics (Index)About

Jeans anisotropic modeling

(JAM, Jeans anisotropic multi-Gaussian expansion, Jeans anisotropic MGE)
(method of determining stellar kinematics of early type galaxies)

Jeans anisotropic modeling (JAM) is a method of determining the stellar kinematics of early-type galaxies. It uses multi-Gaussian expansion (MGE) to fit the Jeans equations to photometric data of the galaxy without presuming symmetry (isotropy) in the distribution of the motion of its stars. Such symmetry would lead to a galaxy symmetric around a point, and JAM's "anisotropy modeling" accommodates triaxial galaxies that lack such symmetry. The term multi-Gaussian expansion was coined in the 1990s for a technique to determine stellar kinematics consistent with an image of a distant galaxy, treating the image as a convolution of Gaussian functions, with such functions to modeling the velocity dispersions as well as to model the point-spread functions of the images. JAM particularly accommodates anisotropy through parameterizing the function modeling the velocity dispersion.


(technique,models,galaxies)
Further reading:
https://ui.adsabs.harvard.edu/abs/2008MNRAS.390...71C/abstract
https://arxiv.org/abs/1211.7009
https://www2.mpia-hd.mpg.de/~dynamics/ringberg/files/cappellari1.pdf
http://www.ifa.hawaii.edu/~barnes/ast626_01/jta.pdf
https://ui.adsabs.harvard.edu/abs/1994A%26A...285..723E/abstract

Index