Classification of magnetized star–planet interactions: bow shocks, tails, and inspiraling flows

Matsakos, T.; Uribe, Ana; Königl, Arieh

doi:10.1051/0004-6361/201425593

Cited by 145 publications

(187 citation statements)

References 77 publications

Supporting

Mentioning

175

Contrasting

Order By: Relevance

“…is significantly smaller than the relevant length scales, thus the motion of the ionized gas can be acceptably treated as a fluid (see Matsakos et al 2015 for a more complete discussion).…”

Section: Mean Free Pathsmentioning

confidence: 99%

See 1 more Smart Citation

Axisymmetric Simulations of Hot Jupiter–stellar Wind Hydrodynamic Interaction

Christie

Arras

2016

ApJ

View full text Add to dashboard Cite

Gas giant exoplanets orbiting at close distances to the parent star are subjected to large radiation and stellar wind fluxes. In this paper, hydrodynamic simulations of the planetary upper atmosphere and its interaction with the stellar wind are carried out to understand the possible flow regimes and how they affect the Lyα transmission spectrum. Following Tremblin and Chiang, charge exchange reactions are included to explore the role of energetic atoms as compared to thermal particles. In order to understand the role of the tail as compared to the leading edge of the planetary gas, the simulations were carried out under axisymmetry, and photoionization and stellar wind electron impact ionization reactions were included to limit the extent of the neutrals away from the planet. By varying the planetary gas temperature, two regimes are found. At high temperature, a supersonic planetary wind is found, which is turned around by the stellar wind and forms a tail behind the planet. At lower temperatures, the planetary wind is shut off when the stellar wind penetrates inside where the sonic point would have been. In this regime mass is lost by viscous interaction at the boundary between planetary and stellar wind gases. Absorption by cold hydrogen atoms is large near the planetary surface, and decreases away from the planet as expected. The hot hydrogen absorption is in an annulus and typically dominated by the tail, at large impact parameter, rather than by the thin leading edge of the mixing layer near the substellar point.

show abstract

“…is significantly smaller than the relevant length scales, thus the motion of the ionized gas can be acceptably treated as a fluid (see Matsakos et al 2015 for a more complete discussion).…”

Section: Mean Free Pathsmentioning

confidence: 99%

“…Some of these effects are treated in, e.g., Murray-Clay et al (2009), Vidotto et al (2011), Cohen et al (2011a, 2011b, Bisikalo et al (2013), Matsakos et al (2015).…”

Section: Introductionmentioning

confidence: 99%

Axisymmetric Simulations of Hot Jupiter–stellar Wind Hydrodynamic Interaction

Christie

Arras

2016

ApJ

View full text Add to dashboard Cite

show abstract

“…However, several studies addressed the interaction between a closein planet with the host star's wind, but some of them neglected magnetic fields and all just considered a purely hydrodynamic interaction (Stone & Proga 2009;Bisikalo et al 2013;Tremblin & Chiang 2013;Christie et al 2016). Other studies, instead, applied MHD models (Cohen et al 2011;Matsakos et al 2015;Tilley et al 2016), but employing mostly simplified descriptions of the planetary wind.…”

Section: Introductionmentioning

confidence: 99%

Effect of stellar wind induced magnetic fields on planetary obstacles of non-magnetized hot Jupiters

Еркаев

Odert

Lämmer

et al. 2017

Monthly Notices of the Royal Astronomical Society

View full text Add to dashboard Cite

We investigate the interaction between the magnetized stellar wind plasma and the partially ionized hydrodynamic hydrogen outflow from the escaping upper atmosphere of non-or weakly magnetized hot Jupiters. We use the well-studied hot Jupiter HD 209458b as an example for similar exoplanets, assuming a negligible intrinsic magnetic moment. For this planet, the stellar wind plasma interaction forms an obstacle in the planet's upper atmosphere, in which the position of the magnetopause is determined by the condition of pressure balance between the stellar wind and the expanded atmosphere, heated by the stellar extreme ultraviolet (EUV) radiation. We show that the neutral atmospheric atoms penetrate into the region dominated by the stellar wind, where they are ionized by photo-ionization and charge exchange, and then mixed with the stellar wind flow. Using a 3D magnetohydrodynamic (MHD) model, we show that an induced magnetic field forms in front of the planetary obstacle, which appears to be much stronger compared to those produced by the solar wind interaction with Venus and Mars. Depending on the stellar wind parameters, because of the induced magnetic field, the planetary obstacle can move up to ≈0.5-1 planetary radii closer to the planet. Finally, we discuss how estimations of the intrinsic magnetic moment of hot Jupiters can be inferred by coupling hydrodynamic upper planetary atmosphere and MHD stellar wind interaction models together with UV observations. In particular, we find that HD 209458b should likely have an intrinsic magnetic moment of 10-20% that of Jupiter.

show abstract

“…The physical interpretations of these abnormalities vary, and include bow shocks, tidal interactions, starplanet magnetic interactions, a plasma torus originating from an active satellite, or escaping planetary atmospheres (e.g. Lai, Helling & van den Heuvel 2010;Vidotto, Jardine & Helling 2010;Ben-Jaffel & Ballester 2014;Matsakos, Uribe & Königl 2015).…”

Section: Introductionmentioning

confidence: 99%

Ground-based near-UV observations of 15 transiting exoplanets: constraints on their atmospheres and no evidence for asymmetrical transits

Turner

Pearson

Biddle

et al. 2016

Mon. Not. R. Astron. Soc.

107

View full text Add to dashboard Cite

Transits of exoplanets observed in the near-UV have been used to study the scattering properties of their atmospheres and possible star-planet interactions. We observed the primary transits of 15 exoplanets (CoRoT-1b, GJ436b, HAT-P-1b, HAT-P-13b, HAT-P-16b, HAT-P-22b, TrES2b, in the near-UV and several optical photometric bands to update their planetary parameters, ephemerides, search for a wavelength dependence in their transit depths to constrain their atmospheres, and determine if asymmetries are visible in their light curves. Here, we present the first ground-based near-UV light curves for 12 of the targets (CoRoT1b, GJ436b, HAT-P-1b, HAT-P-13b, HAT-P-22b, TrES-2b, TrES-4b, WASP-1b, WASP-33b, WASP-36b, WASP-48b, and WASP-77Ab). We find that none of the near-UV transits exhibit any non-spherical asymmetries, this result is consistent with recent theoretical predictions by Ben-Jaffel et al. and Turner et al. The multiwavelength photometry indicates a constant transit depth from near-UV to optical wavelengths in 10 targets (suggestive of clouds), and a varying transit depth with wavelength in 5 targets (hinting at Rayleigh or aerosol scattering in their atmospheres). We also present the first detection of a smaller near-UV transit depth than that measured in the optical in WASP-1b and a possible opacity source that can cause such radius variations is currently unknown. WASP-36b also exhibits a smaller near-UV transit depth at

show abstract

Classification of magnetized star–planet interactions: bow shocks, tails, and inspiraling flows

Cited by 145 publications

References 77 publications

Axisymmetric Simulations of Hot Jupiter–stellar Wind Hydrodynamic Interaction

Axisymmetric Simulations of Hot Jupiter–stellar Wind Hydrodynamic Interaction

Effect of stellar wind induced magnetic fields on planetary obstacles of non-magnetized hot Jupiters

Ground-based near-UV observations of 15 transiting exoplanets: constraints on their atmospheres and no evidence for asymmetrical transits

Contact Info

Product

Resources

About