INFLATING HOT JUPITERS WITH OHMIC DISSIPATION

By K. Batygin, D. Stevenson. 2010

177 citations recorded by the source corpus.

We present a new, magnetohydrodynamic mechanism for inflation of close-in giant extrasolar planets. The idea behind the mechanism is that current, which is induced through interaction of atmospheric winds and the planetary magnetic field, results in significant Ohmic dissipation of energy in the interior. We develop an analytical model for computation of interior Ohmic dissipation, with a simplified treatment of the atmosphere. We apply our model to HD209458b, Tres-4b, and HD189733b. With conservative assumptions for wind speed and field strength, our model predicts a generated power that appears to be large enough to maintain the transit radii, opening an unexplored avenue toward solving a decade-old puzzle of extrasolar gas giant radius anomalies.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/f94a59142b4d8b2202f28d06f160395028c4ce71

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Astronomy and Astrophysics

1. Jon Fortney
2. D. Charbonneau
3. Timothy Morton
4. J. Johnson
5. G. Marcy
6. J. Winn
7. Andrew W. Howard
8. Sara Seager

In Instrumentation

1. D. Charbonneau
2. Jon Fortney
3. Timothy Morton
4. J. Southworth
5. J. Johnson
6. J. Winn
7. G. Marcy
8. Andrew W. Howard

Citations in the corpus

• The prevalence of dust on the exoplanet HD 189733b from Hubble and Spitzer observations (2012, background): “The two leading candidates are (i) deep dissipation of the day-night currents (Showman & Guillot 2002) (ii) magnetic drag (Batygin & Stevenson 2010; Perna et al. 2010).”
• The escape of heavy atoms from the ionosphere of HD209458b. I. A photochemical–dynamical model of the thermosphere (2012, background): “, Batygin and Stevenson, 2010), although we find photoionization to be more significant in the thermosphere (see Section 3.2). In order to simulate photochemistry in a numerically robust fashion, we coupled the dynamical model with the ASAD chemistry integrator developed at the University of Cambrid”
• THE MASS OF KOI-94d AND A RELATION FOR PLANET RADIUS, MASS, AND INCIDENT FLUX (2013, background): “These mechanisms are discussed in a variety of papers: weather layer kinetic energy transport (Showman & Guillot 2002; Guillot & Showman 2002), Ohmic dissipation (Batygin & Stevenson 2010; Perna et al. 2010), thermal tides (Arras & Socrates 2010), and mechanical greenhouse (Youdin & Mitchell 2010).”
• PLANET OCCURRENCE WITHIN 0.25 AU OF SOLAR-TYPE STARS FROM KEPLER (2011, background): “Larger planets are typically young or close-in and inflated by one of several proposed mechanisms (e.g., Batygin & Stevenson 2010; Laughlin et al. 2011; Burrows et al. 2007).”
• LACK OF INFLATED RADII FOR KEPLER GIANT PLANET CANDIDATES RECEIVING MODEST STELLAR IRRADIATION (2011, background): “Electrical current generated through the interaction of ionized particles with the planetary magnetic field causes a dissipation of energy in the planetary interior (Batygin & Stevenson 2010).”
• Mathematical and physical ideas for climate science (2013, background): “Another dissipative mechanism believed to be a common feature in planetary atmospheres is shock wave breaking (Batygin and Stevenson, 2010; Heng , 2012b).”
• Characterization of exoplanets from their formation - I. Models of combined planet formation and evolution (2012, background): “…several possible physical mechanisms leading to this bloating, such as tidal heating (Bodenheimer et al. 2001), dissipation of stellar irradiation deep in the interior (Showman & Guillot 2002), ohmic dissipation (Batygin & Stevenson 2010), and double diffusive convection (Chabrier & Baraffe 2007).”
• WASP-121 b: a hot Jupiter close to tidal disruption transiting an active F star (2015, background): “…(Showman & Guillot 2002), enhanced atmospheric opacities (Burrows et al. 2007), reduced heat transport efficiency by layered convection inside the planets (Chabrier & Baraffe 2007), or Ohmic heating from currents induced through winds in the planetary atmospheres (Batygin & Stevenson 2010).”
• ON THE ANOMALOUS RADII OF THE TRANSITING EXTRASOLAR PLANETS (2011, methodology): “Second, we follow Batygin & Stevenson (2010) and assume that the Elsasser Number, Λ = σiB 2/2ρΩ, is roughly constant across the aggregate of transiting planets.”