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Title: Stars get dizzy after lunch

Abstract

Exoplanet searches have discovered a large number of {sup h}ot Jupiters{sup —}high-mass planets orbiting very close to their parent stars in nearly circular orbits. A number of these planets are sufficiently massive and close-in to be significantly affected by tidal dissipation in the parent star, to a degree parameterized by the tidal quality factor Q {sub *}. This process speeds up their star's rotation rate while reducing the planet's semimajor axis. In this paper, we investigate the tidal destruction of hot Jupiters. Because the orbital angular momenta of these planets are a significant fraction of their star's rotational angular momenta, they spin up their stars significantly while spiraling to their deaths. Using the Monte Carlo simulation, we predict that for Q {sub *} = 10{sup 6}, 3.9 × 10{sup –6} of stars with the Kepler Target Catalog's mass distribution should have a rotation period shorter than 1/3 day (8 hr) due to accreting a planet. Exoplanet surveys such as SuperWASP, HATnet, HATsouth, and KELT have already produced light curves of millions of stars. These two facts suggest that it may be possible to search for tidally destroyed planets by looking for stars with extremely short rotational periods, then looking formore » remnant planet cores around those candidates, anomalies in the metal distribution, or other signatures of the recent accretion of the planet.« less

Authors:
 [1];  [2]
  1. Department of Astrophysical Sciences, Princeton University, 5491 Frist Center, Princeton, NJ 08544 (United States)
  2. Department of Astrophysical Sciences, Princeton University, 4 Ivy Lane, Peyton Hall, Princeton, NJ 08544 (United States)
Publication Date:
OSTI Identifier:
22356775
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 787; 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; ACCRETION DISKS; COMPUTERIZED SIMULATION; CONVECTION; INTERACTIONS; JUPITER PLANET; MASS DISTRIBUTION; METALS; MONTE CARLO METHOD; ORBITAL ANGULAR MOMENTUM; QUALITY FACTOR; ROTATION; SPIN; STARS; VELOCITY; VISIBLE RADIATION

Citation Formats

Zhang, Michael, and Penev, Kaloyan. Stars get dizzy after lunch. United States: N. p., 2014. Web. doi:10.1088/0004-637X/787/2/131.
Zhang, Michael, & Penev, Kaloyan. Stars get dizzy after lunch. United States. doi:10.1088/0004-637X/787/2/131.
Zhang, Michael, and Penev, Kaloyan. 2014. "Stars get dizzy after lunch". United States. doi:10.1088/0004-637X/787/2/131.
@article{osti_22356775,
title = {Stars get dizzy after lunch},
author = {Zhang, Michael and Penev, Kaloyan},
abstractNote = {Exoplanet searches have discovered a large number of {sup h}ot Jupiters{sup —}high-mass planets orbiting very close to their parent stars in nearly circular orbits. A number of these planets are sufficiently massive and close-in to be significantly affected by tidal dissipation in the parent star, to a degree parameterized by the tidal quality factor Q {sub *}. This process speeds up their star's rotation rate while reducing the planet's semimajor axis. In this paper, we investigate the tidal destruction of hot Jupiters. Because the orbital angular momenta of these planets are a significant fraction of their star's rotational angular momenta, they spin up their stars significantly while spiraling to their deaths. Using the Monte Carlo simulation, we predict that for Q {sub *} = 10{sup 6}, 3.9 × 10{sup –6} of stars with the Kepler Target Catalog's mass distribution should have a rotation period shorter than 1/3 day (8 hr) due to accreting a planet. Exoplanet surveys such as SuperWASP, HATnet, HATsouth, and KELT have already produced light curves of millions of stars. These two facts suggest that it may be possible to search for tidally destroyed planets by looking for stars with extremely short rotational periods, then looking for remnant planet cores around those candidates, anomalies in the metal distribution, or other signatures of the recent accretion of the planet.},
doi = {10.1088/0004-637X/787/2/131},
journal = {Astrophysical Journal},
number = 2,
volume = 787,
place = {United States},
year = 2014,
month = 6
}
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