Kinematics and Dynamics of Galactic Stellar Populations

Download or read book Kinematics and Dynamics of Galactic Stellar Populations written by Rafael Cubarsi and published by Cambridge Scholars Publishing. This book was released on 2018-07-27 with total page 223 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stellar dynamics is an interdisciplinary field where mathematics, statistics, physics, and astronomy overlap. The approaches to studying a stellar system include dealing with the collisionless Boltzmann equation, the Chandrasekhar equations, and stellar hydrodynamic equations, which are comparable to the equations of motion of a compressible viscous fluid. Their equivalence gives rise to the closure problem, connected with the higher-order moments of the stellar velocity distribution, which is explained and solved for maximum entropy distributions and for any velocity distribution function, depending on a polynomial function in the velocity variables. On the other hand, the Milky Way kinematics in the solar neighbourhood needs to be described as a mixture distribution accounting for the stellar populations composing the Galactic components. As such, the book offers a statistical study, according to the moments and cumulants of a population mixture, and a dynamical approach, according to a superposition of Chandrasekhar stellar systems, connected with the potential function and the symmetries of the model.