Related papers: Inflated planets and their low-mass companions
We use a series of N-body/smoothed particle hydrodynamics simulations and analytic arguments to show that the presence of an effective temperature floor in the interstellar medium at T_F ~ 10^4 K naturally explains the tendency for low-mass…
Low-mass white dwarfs (LMWDs) are believed to be exclusive products of binary evolution, as the Universe is not yet old enough to produce them from single stars. Because of the strong tidal forces operating during the binary interaction…
We report the detections of planetary companions orbiting around three evolved intermediate-mass stars from precise radial velocity measurements at Okayama Astrophysical Observatory. HD 2952 (K0III, 2.5 M_sun) and omega Ser (G8III, 2.2…
The {\it Kepler} mission revealed a population of compact multiple-planet systems with orbital periods shorter than a year, and occasionally even shorter than a day. By analyzing a sample of 102 {\it Kepler} and {\it K2} multi-planet…
After finding more planets than expected at the shortest period, there has been an effort to explain their numbers by weak tidal friction. However, we find that the strength of tidal dissipation that would produce the occurence distribution…
Despite decades of inquiry, the origin of giant planets residing within a few tenths of an astronomical unit from their host stars remains unclear. Traditionally, these objects are thought to have formed further out before subsequently…
Surveys of nearby field stars indicate that stellar binaries are common, yet little is known about the effects that these companions may have on planet formation and evolution. The Friends of Hot Jupiters project uses three complementary…
The exotic range of known planetary systems has provoked an equally exotic range of physical explanations for their diverse architectures. However, constraining formation processes requires mapping the observed exoplanet population to that…
Recent discoveries have revealed a population of "popcorn planets" that have masses similar to that of Neptune but radii comparable to Jupiter, leading to exceptionally low bulk densities $\rho_p \lesssim 0.3\,\mathrm{g}\,\mathrm{cm}^{-3}$.…
Young intermediate-mass stars have become high-priority targets for direct-imaging planet searches following the recent discoveries of planets orbiting e.g. HR 8799 and Beta Pictoris. Close stellar companions to these stars can affect the…
During planet formation, a gas giant will interact with smaller protoplanets that stray within its sphere of gravitational influence. We investigate the outcome of interactions between gas giants and terrestrial-sized protoplanets with…
Planets form in disks around young stars. Interactions with these disks cause them to migrate and thus affect their final orbital periods. We suggest that the connection between planets and disks may be deeper and involve a symbiotic…
The currently feasible method of detection of Earth-mass planets is transit photometry, with detection probability decreasing with a planet's distance from the star. The existence or otherwise of short-period terrestrial planets will tell…
A small fraction of red giants are known to be lithium (Li) rich, in contradiction with expectations from stellar evolutionary theory. A possible explanation for these atypical giants is the engulfment of a Li-rich planet or brown dwarf by…
We present four new exoplanets: HIP 14810 b & c, HD 154345 b, and HD 187123 c. The two planets orbiting HIP 14810, from the N2K project, have masses of 3.9 and 0.76 M_jup. We have searched the radial velocity time series of 90 known…
The formation scenarios for single low-mass (M < 0.45 Msol) white dwarfs include enhanced mass loss from a metal-rich progenitor star or a common envelope phase of a solar-like star with a close-in massive planet or a brown dwarf. Both…
Previous models of the combined growth and migration of protoplanets needed large ad hoc reduction factors for the type I migration rate as found in the isothermal approximation. In order to eliminate these factors, a simple semi-analytical…
Planets orbiting a planetesimal circumstellar disc can migrate inward from their initial positions because of dynamical friction between planets and planetesimals. The migration rate depends on the disc mass and on its time evolution.…
Discoveries of planet- and stellar remnant-hosting pulsars challenge our understanding as the violent supernova explosion that forms the pulsar presumably destabilizes the system. Type II supernova explosions lead to the formation of…
There exists a positive correlation between orbital eccentricity and the average stellar flux that planets receive from their parent star. Often, though, it is assumed that the average equilibrium temperature would correspondingly increase…