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Title: An Advanced N -body Model for Interacting Multiple Stellar Systems

Abstract

We construct an advanced model for interacting multiple stellar systems in which we compute all trajectories with a numerical N -body integrator, namely the Bulirsch–Stoer from the SWIFT package. We can then derive various observables: astrometric positions, radial velocities, minima timings (TTVs), eclipse durations, interferometric visibilities, closure phases, synthetic spectra, spectral energy distribution, and even complete light curves. We use a modified version of the Wilson–Devinney code for the latter, in which the instantaneous true phase and inclination of the eclipsing binary are governed by the N -body integration. If all of these types of observations are at one’s disposal, a joint χ {sup 2} metric and an optimization algorithm (a simplex or simulated annealing) allow one to search for a global minimum and construct very robust models of stellar systems. At the same time, our N -body model is free from artifacts that may arise if mutual gravitational interactions among all components are not self-consistently accounted for. Finally, we present a number of examples showing dynamical effects that can be studied with our code and we discuss how systematic errors may affect the results (and how to prevent this from happening).

Authors:
 [1]
  1. Astronomical Institute of the Charles University, Faculty of Mathematics and Physics, V Holešovičkách 2, CZ-18000 Praha 8 (Czech Republic)
Publication Date:
OSTI Identifier:
22661119
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal, Supplement Series; Journal Volume: 230; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ALGORITHMS; DIAGRAMS; ECLIPSE; ENERGY SPECTRA; GRAVITATIONAL INTERACTIONS; INCLINATION; METRICS; OPTIMIZATION; RADIAL VELOCITY; STAR CLUSTERS; STARS; VISIBILITY; VISIBLE RADIATION

Citation Formats

Brož, Miroslav. An Advanced N -body Model for Interacting Multiple Stellar Systems. United States: N. p., 2017. Web. doi:10.3847/1538-4365/AA7207.
Brož, Miroslav. An Advanced N -body Model for Interacting Multiple Stellar Systems. United States. doi:10.3847/1538-4365/AA7207.
Brož, Miroslav. Thu . "An Advanced N -body Model for Interacting Multiple Stellar Systems". United States. doi:10.3847/1538-4365/AA7207.
@article{osti_22661119,
title = {An Advanced N -body Model for Interacting Multiple Stellar Systems},
author = {Brož, Miroslav},
abstractNote = {We construct an advanced model for interacting multiple stellar systems in which we compute all trajectories with a numerical N -body integrator, namely the Bulirsch–Stoer from the SWIFT package. We can then derive various observables: astrometric positions, radial velocities, minima timings (TTVs), eclipse durations, interferometric visibilities, closure phases, synthetic spectra, spectral energy distribution, and even complete light curves. We use a modified version of the Wilson–Devinney code for the latter, in which the instantaneous true phase and inclination of the eclipsing binary are governed by the N -body integration. If all of these types of observations are at one’s disposal, a joint χ {sup 2} metric and an optimization algorithm (a simplex or simulated annealing) allow one to search for a global minimum and construct very robust models of stellar systems. At the same time, our N -body model is free from artifacts that may arise if mutual gravitational interactions among all components are not self-consistently accounted for. Finally, we present a number of examples showing dynamical effects that can be studied with our code and we discuss how systematic errors may affect the results (and how to prevent this from happening).},
doi = {10.3847/1538-4365/AA7207},
journal = {Astrophysical Journal, Supplement Series},
number = 2,
volume = 230,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
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