Data-driven Dynamics with Orbital Torus Imaging: A Flexible Model of the Vertical Phase Space of the Galaxy

• DOI: 10.48550/arxiv.2401.07903
• Publication Date: 2024-01-01
• Authors: Adrian M. Price-W...; John Douglas Hunt; Danny Horta; M. Oeur; David W. Hogg; Kathryn V. Johnston; Lawrence M. Widrow
• Keywords: Stellar kinematics; Orbit (dynamics)

The vertical kinematics of stars near the Sun can be used to measure total mass distribution Galactic disk and study out-of-equilibrium dynamics. With contemporary stellar surveys, tracers dynamics are so numerous well measured that shapes underlying orbits almost directly visible in data through element abundances or even density. These infer a model for Milky Way, enabling constraints on dark matter inner galaxy. Here we present flexible foliating position-velocity phase space with orbits, use data-driven studies acceleration profile vicinity disk, along orbital actions, angles, frequencies individual stars, all derived from orbit foliation. We show this framework - "Orbital Torus Imaging" (OTI) is rigorously justified context dynamical theory, does good job fitting simulated abundance varying degrees realism. OTI (1) not require global Way distribution, (2) detailed modeling selection function input survey data. discuss approximations limitations framework, which currently trades interpretability flexibility representing some regimes, also presently separates radial release an open-source tool, torusimaging, accompany article.