• Media type: E-Article
  • Title: Exploring the dynamics of collisionless spherical stellar systems using the matrix method: Insights from the dilation mode
  • Contributor: Polyachenko, Evgeny V.; Shukhman, Ilia G.
  • Published: EDP Sciences, 2024
  • Published in: Astronomy & Astrophysics, 684 (2024), Seite A58
  • Language: Not determined
  • DOI: 10.1051/0004-6361/202348556
  • ISSN: 0004-6361; 1432-0746
  • Origination:
  • Footnote:
  • Description: <jats:p><jats:italic>Context.</jats:italic> Analytical solutions to the perturbed equations that govern self-gravitating collisionless stellar systems are crucial for both code testing and theoretical insights. For spheres, a solution has been known for years that corresponds to the entire object’s shift from the origin. We recently introduced a new exact stationary solution, relevant for models with a single length parameter. This solution, referred to as the scale-invariant or dilation mode, has led to insights regarding the concept of perturbation energy within the linear theory framework.</jats:p> <jats:p><jats:italic>Aims.</jats:italic> Our aim is to use Hénon’s isochrone model as an example to verify the ability of the standard matrix method to successfully predict the existence of a dilation mode, and to explore its potential application as a test disturbance.</jats:p> <jats:p><jats:italic>Methods.</jats:italic> We used the standard matrix method for radial perturbations and applied Clutton-Brock potential-density pairs to determine the properties of the perturbations.</jats:p> <jats:p><jats:italic>Results.</jats:italic> In this particular case of stationary radial perturbations, the typical relationship between the perturbations of the distribution function and the potential fails. This discrepancy poses a challenge when attempting to use the dilation mode as a test. When using Clutton-Brock pairs with the matrix method, a mass conservation equation as an additional equation to the ordinary set of linear equations is required. With this added equation, it’s possible to obtain the needed test: identical vanishing of the determinant of this modified set of equations with an increasing number of included basis functions.</jats:p>
  • Access State: Open Access