Abstract
Recently, Fossati et al. observed that the near-UV transit light curve
of the close-in giant planet WASP-12b shows an early ingress as compared
to its optical transit. Such observations were interpreted as due to the
presence of asymmetries in the exosphere of the planet. In particular,
we suggest that this asymmetry could be explained by the presence of a
shock formed around the planet's magnetosphere. Bow shocks are formed as
a result of the interaction of the planet with the coronal material of
the host star, similar to the one formed around the Earth's
magnetosphere. According to our model, shock detection through transit
observations can be a useful tool to probe and constrain exoplanetary
magnetic field. In the case of WASP- 12b, we derive an upper limit for
the magnetic field of ∼ 24 G. In addition, we predict that observable
shocks should be a common feature in other transiting systems. Promising
candidates are: WASP- 19b, WASP-4b, WASP-18b, CoRoT-7b, HAT-P-7b,
CoRoT-1b, TrES-3 and WASP-5b.
| Original language | English |
|---|---|
| Pages (from-to) | 253 |
| Journal | EPSC-DPS Joint Meeting 2011, held 2-7 October 2011 in Nantes, France |
| Publication status | Published - 1 Oct 2011 |