Spiral Instabilities in N-body Simulations: Emergence from noise II

Abstract

An earlier paper presented the potentially significant discovery that disturbances in simplified simulations of a stellar disc model that was predicted to be stable in linear theory grew to large amplitude over a long period of time. The ultimate appearance of true instabilities was attributed to non-linear scattering by a succession of collective waves excited by shot noise from the finite number of particles. The paper concluded that no finite number of particles, however large, could mimic a smooth disc. As this surprising finding has been challenged as an artifact of the numerical scheme employed, we here present a new calculation of the same model using a different grid geometry that confirms the original behaviour.

Accepted to appear in MNRAS. 4 pages, 2 figures

References in corpus (2)

• Instabilities in disc galaxies: from noise to grooves to spirals
• Secular resonant dressed orbital diffusion II : application to an isolated self similar tepid galactic disc

Cited by in corpus (2)

• Apsidal Clustering following the Inclination Instability
• On the long-term evolution of razor-thin galactic discs: Balescu-Lenard prediction and perspectives