Related papers: A binary merger origin for inflated hot Jupiter pl…
Stripped stars are a common product of binary stellar systems and span a wide mass range from Wolf-Rayet stars to hot subdwarfs and helium white dwarfs. The recent discovery of intermediate-mass stripped stars, with masses between those of…
We have investigated i) the formation of gravitationally bounded pairs of gas-giant planets (which we call "binary planets") from capturing each other through planet-planet dynamical tide during their close encounters and ii) the following…
Discovery of hot Jupiter exo-planets, those with anomalously inflated size and low density relative to Jupiter, has evoked much discussion as to possible sources of internal heat production. But to date, no explanations have come forth that…
The population of giant planets on short-period orbits can potentially be explained by some flavours of high-eccentricity migration. In this paper we investigate one such mechanism involving "secular chaos", in which secular interactions…
It has been shown that hot Jupiters systems with massive, hot stellar primaries exhibit a wide range of stellar obliquities. On the other hand, hot Jupiter systems with low-mass, cool primaries often have stellar obliquities close to zero.…
Understanding the formation of wide binary systems of very low mass stars (M $\le$ 0.1 Msun) is challenging. The most obvious route is via widely separated low-mass collapsing fragments produced through turbulent fragmentation of a…
We present the results of numerical simulations which show the formation of blue compact dwarf (BCD) galaxies from merging between very gas-rich dwarfs with extended HI gas disks. We show that dwarf-dwarf merging can trigger central…
The stellar origin of gamma-ray bursts can be explained by the rapid release of energy in a highly collimated, extremely relativistic jet. This in turn appears to require a rapidly spinning highly magnetised stellar core that collapses into…
Recent simulations show that giant planets of about one Jupiter mass migrate inward at a rate that differs from the Type II prediction. Here we show that at higher masses, planets migrate outward. Our result differs from previous ones…
Young binaries within dense molecular clouds are subject to dynamical friction from ambient gas. Consequently, their orbits decay, with both the separation and period decreasing in time. A simple analytic expression is derived for this…
We investigate the giant planet-metallicity correlation for a homogeneous, unbiased set of 217 hot Jupiters taken from nearly 15 years of wide-field ground-based surveys. We compare the host star metallicity to that of field stars using the…
Rapidly rotating stars are readily produced in binary systems. An accreting star in a binary system can be spun up by mass accretion and quickly approach the break-up limit. Mergers between two stars in a binary are expected to result in…
Recent discoveries of strongly misaligned transiting exoplanets pose a challenge to the established planet formation theory which assumes planetary systems to form and evolve in isolation. However, the fact that the majority of stars…
Context. The birth environments of planetary systems are thought to influence planet formation and orbital evolution, through external photoevaporation and stellar flybys. Recent work has claimed observational support for this, in the form…
We numerically investigate stellar and gaseous dynamical evolution of mergers between five identical late-type disk galaxies with the special emphasis on star formation history and chemical evolution of multiple galaxy mergers. We found…
The discovery of planetary systems outside of the solar system has challenged some of the tenets of planetary formation. Among the difficult-to-explain observations, are systems with a giant planet orbiting a very-low mass star, such as the…
Planetary systems are born in the disks of gas, dust and rocky fragments that surround newly formed stars. Solid content assembles into ever-larger rocky fragments that eventually become planetary embryos. These then continue their growth…
Hot Jupiters (HJs) are Jupiter-like planets orbiting their host star in tight orbits of a few days. They are commonly believed not to have formed in situ, requiring inwards migration towards the host star. One of the proposed migration…
The favored theoretical explanation for giant planet formation -- in both our solar system and others -- is the core accretion model (although it still has some serious difficulties). In this scenario, planetesimals accumulate to build up…
The existence of hot Jupiters has challenged theories of planetary formation since the first extrasolar planets were detected. Giant planets are generally believed to form far from their host stars, where volatile materials like water exist…