Ultra-short-period Planets Are Stable against Tidal Inspiral

On the Tidal In ation of Short-Period Extrasolar Planets

Absence of a Metallicity Effect for Ultra-short-period Planets

Ultra-short-period (USP) planets are a newly recognized class of planets with periods shorter than one day, and radii smaller than about 2 R⊕. It has been proposed that USP planets are the solid cores of hot Jupiters that lost their gaseous envelopes due to photo-evaporation or Roche lobe overflow. We test this hypothesis by asking whether USP planets are associated with metal-rich stars, as ha...

The Internal Structural Adjustment due to Tidal Heating of Short - Period Inflated Giant Planets

Several short-period Jupiter-mass planets have been discovered around nearby solar-type stars. During the circularization of their orbits, the dissipation of tidal disturbance by their host stars heats the interior and inflates the sizes of these planets. Based on a series of internal structure calculations for giant planets, we examine the physical processes which determine their luminosity-ra...

Tidal interaction in binary-black-hole inspiral.

Tidal torque may lead to important effects in the strong field interaction at the end point of the inspiral of two rapidly rotating black holes. We point out here that in such a case the exchange of spin and orbital angular momentum may significantly affect the energy and waveform of late stage gravitational waves, and may play an important role in the shedding of excess angular momentum. We ar...

Ultra-Short Period Double-Degenerate Binaries

We review the current observational status of the ROSAT sources RX J1914.4+2456 and RX J0806.3+1527, and the evidence that these are ultra-short period (< 10 min) binary systems. We argue that an Intermediate Polar interpretation can be ruled out, that they are indeed compact binaries with a degenerate secondary, and that the period seen in the X-ray and optical is the orbital period. A white d...