Related papers: A Tendency Toward Alignment in Single-Star Warm Ju…
Two formation scenarios have been proposed to explain the tight orbits of hot Jupiters. They could be formed in orbits with a small inclination (with respect to the stellar spin) via disk migration, or in more highly inclined orbits via…
Stellar obliquities, or spin-orbit angles, prevalent in exoplanet systems, can impose important constraints on their formation and evolution histories. Recent studies suggest that primordial misalignments between protoplanetary disks and…
The angle between the spin axis of the host star and the orbit of its planets (i.e., the stellar obliquity) is precious information about the formation and evolution of exoplanetary systems. Measurements of the Rossiter-McLaughlin effect…
TOI-677 b is part of an emerging class of ``tidally-detached'' gas giants ($a/R_\star \gtrsim 11$) that exhibit large orbital eccentricities and yet low stellar obliquities. Such sources pose a challenge for models of giant planet…
For transiting planets, the Rossiter-McLaughlin effect allows the measurement of the sky-projected angle beta between the stellar rotation axis and a planet's orbital axis. Using the HARPS spectrograph, we observed the Rossiter-McLaughlin…
The discovery of Jupiter-mass planets in close orbits about their parent stars has challenged models of planet formation. Recent observations have shown that a number of these planets have highly inclined, sometimes retrograde orbits about…
While many hot Jupiter systems have a measured obliquity, few warm Jupiter systems do. The longer orbital periods and transit durations of warm Jupiters make it more difficult to measure the obliquities of their host stars. However, the…
Exoplanetary systems hosting multiple low-mass planets are thought to have experienced dynamical instability, during which planet-planet collisions and mergers occur; these collisions can impart substantial amount of angular momentum to the…
Tidal friction is thought to be important in determining the long-term spin-orbit evolution of short-period extrasolar planetary systems. Using a simple model of the orbit-averaged effects of tidal friction, we study the evolution of…
Stars hosting hot Jupiters are often observed to have high obliquities, whereas stars with multiple co-planar planets have been seen to have low obliquities. This has been interpreted as evidence that hot-Jupiter formation is linked to…
We investigate tidal dissipation of obliquity in hot Jupiters. Assuming an initial random orientation of obliquity and parameters relevant to the observed population, the obliquity of hot Jupiters does not evolve to purely aligned systems.…
It is debated whether the two hot Jupiter populations --- those on orbits misaligned from their host star's spin axis and those well-aligned --- result from two migration channels or from two tidal realignment regimes. Here I demonstrate…
The spin-orbit angle, or obliquity, is a powerful observational marker that allows us to access the dynamical history of exoplanetary systems. Here, we have examined the distribution of spin-orbit angles for close-in exoplanets and put it…
Observations of hot Jupiters around solar-type stars with very short orbital periods (~day) suggest that tidal dissipation in such stars is not too efficient so that these planets can survive against rapid orbital decay. This is consistent…
Through the Rossiter-McLaughlin effect, several hot Jupiters have been found to exhibit spin-orbit misalignment, and even retrograde orbits. The high obliquity observed in these planets can be attributed to two primary formation mechanisms,…
Many of the observed spin--orbit alignment properties of exoplanets can be explained in the context of the primordial disk misalignment model, in which an initially aligned protoplanetary disk is torqued by a distant stellar companion on a…
We present a pattern emerging from stellar obliquity measurements in single-star systems: planets with high planet-to-star mass ratios ($M_{\rm p}/M{_*}$$>$ $2\times10^{-3}$) -- such as super-Jupiters, brown dwarf companions, and M-dwarfs…
The presence of gaseous giant planets whose orbits lie in extreme proximity to their host stars ("hot Jupiters"), can largely be accounted for by planetary migration, associated with viscous evolution of proto-planetary nebulae. Recently,…
Exoplanets are organized in a broad array of orbital configurations that reflect their formation along with billions of years of dynamical processing through gravitational interactions. This history is encoded in the angular momentum…
High-eccentricity migration is a likely formation mechanism for many observed hot Jupiters, particularly those with a large misalignment between the stellar spin axis and orbital angular momentum axis of the planet. In one version of…