Forward modeling the orbits of companions to pulsating stars from their light travel time variations
| Autor: | Benjamin J. S. Pope, Simon J. Murphy, Daniel R. Hey, David W. Hogg, Timothy R. Bedding, Daniel Foreman-Mackey |
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| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Physics
Subdwarf B star 010504 meteorology & atmospheric sciences FOS: Physical sciences Astronomy and Astrophysics Astrophysics Light curve 01 natural sciences Exoplanet Radial velocity Gravitation Stars Astrophysics - Solar and Stellar Astrophysics Space and Planetary Science Planet 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) Jupiter mass 0105 earth and related environmental sciences |
| Zdroj: | Hey, D R, Murphy, S J, Foreman-Mackey, D, Bedding, T R, Pope, B J S & Hogg, D W 2020, ' Forward Modeling the Orbits of Companions to Pulsating Stars from Their Light Travel Time Variations ', Astronomical Journal, vol. 159, no. 5, 202 . https://doi.org/10.3847/1538-3881/ab7d38 |
| Popis: | Mutual gravitation between a pulsating star and an orbital companion leads to a time-dependent variation in path length for starlight traveling to Earth. These variations can be used for coherently pulsating stars, such as the {\delta} Scuti variables, to constrain the masses and orbits of their companions. Observing these variations for {\delta} Scuti stars has previously relied on subdividing the light curve and measuring the average pulsation phase in equally sized subdivisions, which leads to under-sampling near periapsis. We introduce a new approach that simultaneously forward-models each sample in the light curve and show that this method improves upon current sensitivity limits - especially in the case of highly eccentric and short-period binaries. We find that this approach is sensitive enough to observe Jupiter mass planets around {\delta} Scuti stars under ideal conditions, and use gravity-mode pulsations in the subdwarf B star KIC 7668647 to detect its companion without radial velocity data. We further provide robust detection limits as a function of the SNR of the pulsation mode and determine that the minimum detectable light travel time amplitude for a typical Kepler {\delta} Scuti is around 2 s. This new method significantly enhances the application of light travel time variations to detecting short period binaries with pulsating components, and pulsating A-type exoplanet host stars, especially as a tool for eliminating false positives. Comment: 14 pages, accepted for publication in AJ |
| Databáze: | OpenAIRE |
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