相关论文: Unseen companions of V Hya inferred from periodic …
Based on two decades of radial velocity (RV) observations using Keck/HIRES and McDonald/Tull, and more recent observations using the Automated Planet Finder, we found that the nearby star HR 5183 (HD 120066) hosts a 3$M_J$ minimum mass…
The systems V819 Her, V2388 Oph, and V1031 Ori are triples comprised of an eclipsing binary orbiting with a distant visual component on a longer orbit. A detailed analysis of these interesting systems, combining the two observational…
We present the first results of a Kepler survey of 41 eclipsing binaries that we undertook to search for third star companions. Such tertiaries will periodically alter the eclipse timings through light travel time and dynamical effects. We…
Stellar companion of a black hole orbiting in an eccentric orbit will experience modulating tidal force with a periodicity same as that of the orbital period. This, in turn, would modulate accretion rates, and the seed photon flux which are…
Exoplanetary systems are found not only among single stars, but also binaries of widely varying parameters. Binaries with separations of 100--1000 au are prevalent in the Solar neighborhood; at these separations planet formation around a…
The aim of the project is to improve our knowledge on the multiplicity of planet-host stars at wide physical separations. We cross-matched approximately 6200 square degree area of the Southern sky imaged by the Visible Infrared Survey…
Although comparatively bright, the cataclysmic variable GY Hya has not attracted much attention in the past. As part of a project to better characterize such systems photometrically, we observed light curves in white light, each spanning…
We carry out a comprehensive study of supernova ejecta-companion interaction in massive binary systems. We aim to physically understand the kinematics of the interaction and predict observational signatures. To do this we perform…
Using the partially completed Submillimeter Array with five antennas, we have observed the CO J=2-1 and 3-2 emission from the envelope surrounding the carbon star V Hya. The high-angular resolution (2"-4") maps show that V Hya is powering a…
We analyse the dynamics of the multiple planet system HD 181433. This consists of two gas giant planets (c and d) with msin i = 0.65 MJup and 0.53 MJup orbiting with periods 975 and 2468 days, respectively. The two planets appear to be in a…
There are several on-going projects to search for stars orbiting around an invisible companion. A fraction of such candidates may be a triple, instead of a binary, consisting of an inner binary black hole (BBH) and an outer orbiting star.…
It has been suggested that besides stellar companions, substellar objects in close orbits may be able to trigger mass loss in a common envelope phase and form hot subdwarfs. In an ongoing project we search for close substellar companions…
We report the detection of a extrasolar planet candidate orbiting the G1 V star HD 39091. The orbital period is 2083 d and the eccentricity is 0.62. With a minimum (M sin $i$) mass of 10.3 M$_{\rm JUP}$ this object falls near the high mass…
Outflows play a key role in the star and planet formation processes. Some outflows show discrete clumps of cold molecular gas moving at extremely high velocities (EHVs) of $\sim$100 km s$^{-1}$, known as ''molecular bullets'', that are…
KIC 8462852 is a star in the Kepler field that exhibits almost unique behaviour. The deep, irregular and aperiodic dips in its light curve have been interpreted as the breakup of a large exocomet on a highly eccentric orbit whose…
We discuss two multiple star systems that host known exoplanets: HD 2638 and 30 Ari B. Adaptive optics imagery revealed an additional stellar companion to both stars. We collected multi-epoch images of the systems with Robo-AO and the…
Some fast radio bursts (FRBs) exhibit repetitive behaviors and their origins remain enigmatic. It has been argued that repeating FRBs could be produced by the interaction between a neutron star and an asteroid belt. Here we consider the…
Context: Interferometric observations of various nearby main-sequence stars show an unexpected infrared excess, raising the question of its origin. The two dominant interpretations favor hot exozodiacal dust or a faint companion, as both…
The young nearby solar-type star HD 91962 is a rare quadruple system where three companions revolve around the main component with periods of 170.3 days, 8.85 years, and 205 years. The two outer orbits are nearly co-planar, and all orbits…
We report the discovery of a companion to the high proper motion star LHS 1589, a nearby high-velocity, low-mass subdwarf. The companion (LHS 1589B) is located 0.224+/-0.004" to the southwest of the primary (LHS 1589A), and is 0.5 magnitude…