Measuring bar pattern speeds from single simulation snapshots
Walter Dehnen, Marcin Semczuk, Ralph Schönrich
Abstract
ABSTRACT We describe methods to measure simultaneously the orientation angle ψ and pattern speed Ω from single snapshots of simulated barred galaxies. Unlike previous attempts, our approach is unbiased, precise, and consistent in the sense that $\psi=\int\Omega \mathop{}\mathrm{d} t$. It can be extended to obtain the rate and axis of rotation, i.e. the vector $\boldsymbol{\Omega}$. We provide computer code implementing our method.
Topics & Concepts
PhysicsOmegaBar (unit)Measure (data warehouse)GalaxyOrientation (vector space)Code (set theory)Rotation (mathematics)AstrophysicsGeometryQuantum mechanicsComputer scienceMeteorologyMathematicsDatabaseSet (abstract data type)Programming languageGalaxies: Formation, Evolution, PhenomenaAstronomy and Astrophysical ResearchRadio Astronomy Observations and Technology