On the ultraviolet anomalies of the WASP-12 and HD 189733 systems: Trojan satellites as a plasma source

Описание

Тип публикации: статья из журнала

Год издания: 2016

Идентификатор DOI: 10.1093/mnras/stw1110

Ключевые слова: planets and satellites: atmospheres, planets and satellites: dynamical evolution and stability, planets and satellites: individual: WASP-12b, planets and satellites: individual: HD 189733b, planet-star interactions, stars: activity, Planets and satellites: individual:WASP-12b

Аннотация: We suggest an additional possible plasma source to explain part of the phenomena observed for the transiting hot Jupiters WASP-12b and HD 189733b in their ultraviolet (UV) light curves. In the proposed scenario, material outgasses from the molten surface of Trojan satellites on tadpole orbits near the Lagrange points L-4 and L-5. WПоказать полностьюe show that the temperature at the orbital location ofWASP-12b is high enough to melt the surface of rocky bodies and to form shallow lava oceans on them. In case of WASP-12b, this leads to the release of elements such as Mg and Ca, which are expected to surround the system. The predicted Mg and Ca outgassing rates from two Io-sizedWASP-12b Trojans are approximate to 2.2 x 10(27) s(-1) and approximate to 2.2 x 10(26) s(-1), respectively. Trojan outgassing can lead to the apparent lack of emission in Mg II h&k and Ca II H&K line cores of WASP-12. For HD 189733b, the mechanism is only marginally possible due to the lower temperature. This may be one of the reasons that could not explain the early ingress of HD 189733b observed in the far-UV C II doublet due to absence of carbon within elements outgassed by molten lava. We investigate the long-term stability region of WASP-12b and HD 189733b in case of planar and inclined motion of these satellites and show that unlike the classical exomoons orbiting the planet, Io-sized Trojans can be stable for the whole systems lifetime.

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Издание

Журнал: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY

Выпуск журнала: Vol. 461, Is. 1

Номера страниц: 988-999

ISSN журнала: 00358711

Место издания: OXFORD

Издатель: OXFORD UNIV PRESS

Персоны

  • Kislyakova K.G. (Space Research Institute,Austrian Academy of Sciences)
  • Lammer H. (Space Research Institute,Austrian Academy of Sciences)
  • Fossati L. (Space Research Institute,Austrian Academy of Sciences)
  • Boudjada M.Y. (Space Research Institute,Austrian Academy of Sciences)
  • Pilat-Lohinger E. (University of Vienna,Department of Astrophysics)
  • Funk B. (University of Vienna,Department of Astrophysics)
  • Schwarz R. (University of Vienna,Department of Astrophysics)
  • Eggl S. (IMCCE Observatoire de Paris,Univ. Lille 1,UPMC)
  • Erkaev N.V. (Siberian Federal University)