Metrics for Optimizing Searches for Tidally Decaying Exoplanets
Tidal interactions between short-period exoplanets and their host stars drive orbital decay and have likely led to engulfment of planets by their stars. Precise transit timing surveys, with baselines now spanning decades for some planets, are directly detecting orbital decay for a handful of planets...
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astronomical Journal |
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| Online Access: | https://doi.org/10.3847/1538-3881/acef00 |
| _version_ | 1797692266671767552 |
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| author | Brian Jackson Elisabeth R. Adams Jeffrey P. Morgenthaler |
| author_facet | Brian Jackson Elisabeth R. Adams Jeffrey P. Morgenthaler |
| author_sort | Brian Jackson |
| collection | DOAJ |
| description | Tidal interactions between short-period exoplanets and their host stars drive orbital decay and have likely led to engulfment of planets by their stars. Precise transit timing surveys, with baselines now spanning decades for some planets, are directly detecting orbital decay for a handful of planets, with corroboration for planetary engulfment coming from independent lines of evidence. More than that, recent observations have perhaps even caught the moment of engulfment for one unfortunate planet. These portentous signs bolster prospects for ongoing surveys, but optimizing such a survey requires considering the astrophysical parameters that give rise to robust timing constraints and large tidal decay rates, as well as how best to schedule observations conducted over many years. The large number of possible targets means it is not feasible to continually observe all planets that might exhibit detectable tidal decay. In this study, we explore astrophysical and observational properties for a short-period exoplanet system that can maximize the likelihood for observing tidally driven transit timing variations. We consider several fiducial observational strategies and real exoplanet systems reported to exhibit decay. We show that moderately frequent (a few transits per year) observations may suffice to detect tidal decay within just a few years. Tidally driven timing variations take time to grow to detectable levels, so we estimate how long that growth takes as a function of timing uncertainties and tidal decay rate and provide thresholds for deciding that tidal decay has been detected. |
| first_indexed | 2024-03-12T02:26:06Z |
| format | Article |
| id | doaj.art-85aba5c83e284f4cacff1918cf1b9740 |
| institution | Directory Open Access Journal |
| issn | 1538-3881 |
| language | English |
| last_indexed | 2024-03-12T02:26:06Z |
| publishDate | 2023-01-01 |
| publisher | IOP Publishing |
| record_format | Article |
| series | The Astronomical Journal |
| spelling | doaj.art-85aba5c83e284f4cacff1918cf1b97402023-09-05T12:47:32ZengIOP PublishingThe Astronomical Journal1538-38812023-01-01166414210.3847/1538-3881/acef00Metrics for Optimizing Searches for Tidally Decaying ExoplanetsBrian Jackson0https://orcid.org/0000-0002-9495-9700Elisabeth R. Adams1https://orcid.org/0000-0002-9131-5969Jeffrey P. Morgenthaler2https://orcid.org/0000-0003-3716-3455Department of Physics, Boise State University , 1910 University Drive, Boise, ID 83725-1570 USAPlanetary Science Institute , 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719, USAPlanetary Science Institute , 1700 East Fort Lowell, Suite 106, Tucson, AZ 85719, USATidal interactions between short-period exoplanets and their host stars drive orbital decay and have likely led to engulfment of planets by their stars. Precise transit timing surveys, with baselines now spanning decades for some planets, are directly detecting orbital decay for a handful of planets, with corroboration for planetary engulfment coming from independent lines of evidence. More than that, recent observations have perhaps even caught the moment of engulfment for one unfortunate planet. These portentous signs bolster prospects for ongoing surveys, but optimizing such a survey requires considering the astrophysical parameters that give rise to robust timing constraints and large tidal decay rates, as well as how best to schedule observations conducted over many years. The large number of possible targets means it is not feasible to continually observe all planets that might exhibit detectable tidal decay. In this study, we explore astrophysical and observational properties for a short-period exoplanet system that can maximize the likelihood for observing tidally driven transit timing variations. We consider several fiducial observational strategies and real exoplanet systems reported to exhibit decay. We show that moderately frequent (a few transits per year) observations may suffice to detect tidal decay within just a few years. Tidally driven timing variations take time to grow to detectable levels, so we estimate how long that growth takes as a function of timing uncertainties and tidal decay rate and provide thresholds for deciding that tidal decay has been detected.https://doi.org/10.3847/1538-3881/acef00Exoplanet dynamicsStar-planet interactionsTransit timing variation method |
| spellingShingle | Brian Jackson Elisabeth R. Adams Jeffrey P. Morgenthaler Metrics for Optimizing Searches for Tidally Decaying Exoplanets The Astronomical Journal Exoplanet dynamics Star-planet interactions Transit timing variation method |
| title | Metrics for Optimizing Searches for Tidally Decaying Exoplanets |
| title_full | Metrics for Optimizing Searches for Tidally Decaying Exoplanets |
| title_fullStr | Metrics for Optimizing Searches for Tidally Decaying Exoplanets |
| title_full_unstemmed | Metrics for Optimizing Searches for Tidally Decaying Exoplanets |
| title_short | Metrics for Optimizing Searches for Tidally Decaying Exoplanets |
| title_sort | metrics for optimizing searches for tidally decaying exoplanets |
| topic | Exoplanet dynamics Star-planet interactions Transit timing variation method |
| url | https://doi.org/10.3847/1538-3881/acef00 |
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