核心概念
orbitize! is a powerful software package for Bayesian modeling of the orbital parameters of resolved binary objects from time series measurements, developed with the needs of the high-contrast imaging community in mind.
要約
The paper describes the latest version 3.0 of the orbitize! software package, which has seen significant enhancements in functionality and accessibility since the release of version 1.0.
Key highlights:
- Ability to jointly fit radial velocity (RV) time series for the primary star together with the secondary companion.
- Capability to jointly fit absolute astrometry of the primary star, including Hipparcos-Gaia catalog of accelerations, Hipparcos intermediate astrometric data, and Gaia astrometry.
- Implementation of a nested sampling backend via dynesty, in addition to the existing MCMC and OFTI posterior computation algorithms.
- Prescriptions for handling multi-planet effects, including Keplerian epicyclic motion and N-body interactions.
- Support for fitting in different orbital bases and applying observation-based priors.
The paper also discusses the comprehensive verification and documentation practices employed for orbitize!, as well as a comparison to similar open-source packages like orvara and octofitter. The authors highlight the unique features and strengths of orbitize! and emphasize the importance of having multiple approaches to address the evolving best practices in the field of orbit fitting.
統計
"The orbital parameters of directly-imaged planets and binary stars can tell us about their present-day dynamics and formation histories (Bowler, 2016), as well as about their inherent physical characteristics (particularly mass, generally called "dynamical mass" when derived from orbital constraints, e.g. Brandt (2021), Lacour et al. (2021))."
"orbitize! is widely used in the exoplanet imaging and binary star communities to translate astrometric data to information about eccentricities (Bowler et al., 2020), obliquities (Bryan et al., 2020), dynamical masses (Lacour et al., 2021), and more."
引用
"orbitize! implements a full stack of automated testing and documentation building practices."
"The philosophy of orbitize! is to, as much as possible, implement multiple approaches to a problem, evidenced by our multiple implementations of radial velocity joint fitting and absolute astrometry joint fitting."