Related papers: Herbig AeBe stars: Multiplicity and consequences
Most of our current understanding of the planet formation mechanism is based on the planet metallicity correlation derived mostly from solar-type stars harbouring gas-giant planets. To achieve a far more reaching grasp on the substellar…
Observational advances over the last decade have enabled high-resolution, interferometric studies of forming multiple systems, statistical surveys of multiplicity in star-forming regions, and new insights into disk evolution and planetary…
H_alpha spectropolarimetry on Herbig Ae/Be stars shows that the innermost regions of intermediate mass (2 -- 15 M_sun) Pre-Main Sequence stars are flattened. This may be the best evidence to date that the higher mass Herbig Be stars are…
The demographic of circumstellar disks, the birthplaces of planets, is diverse and rich in disks featuring rings, gaps, spirals, filaments, and arcs. Many studies revealing these disk structures have focused on objects around single stars…
Observations from optical to centimeter wavelengths have demonstrated that multiple systems of two or more bodies is the norm at all stellar evolutionary stages. Multiple systems are widely agreed to result from the collapse and…
Stars are commonly formed in binary systems, which provide a natural laboratory for studying planet formation in extreme conditions. In our first paper (Paper I) of a series Xie et al. (2011), we have shown that the intermediate stage -…
The near-star environment around young stars is very dynamic with winds, disks, and outflows. These processes are involved in star and planet formation, and influence the formation and habitability of planets around host stars. Even for the…
Substellar multiplicity is a key outcome of the formation process. The biggest challenge for the next decade will be to distinguish between the formation history, environmental conditions, and dynamical evolution leading to the least…
In many evolutionary stages, low- and intermediate-mass stars show signs of mixing of the surface material with material from the interior. To account for all the details revealed by the observations it is necessary to include non-standard…
Most stars with birth masses larger than that of our Sun belong to binary or higher order multiple systems. Similarly, most stars have stellar winds. Radiation pressure and multiplicity create outflows of material that remove mass from the…
This work presents a spectroscopic study of 163 Herbig Ae/Be stars. Amongst these, we present new data for 30 objects. Stellar parameters such as temperature, reddening, mass, luminosity and age are homogeneously determined. Mass accretion…
I review theoretical models of star formation and how they apply across the stellar mass spectrum. Several distinct theories are under active study for massive star formation, especially Turbulent Core Accretion, Competitive Accretion and…
The overall frequency and other statistical properties of binary systems suggest that star formation is intrinsically a complex and chaotic process, and that most binaries and single stars actually originate from the decay of multiple…
The formation and evolution of planetary systems are linked to their host stellar environment. In this study, we employ a pebble accretion-based planet population synthesis model to explore the correlation between planetary properties and…
The formation of stars, particularly the high-mass star formation, poses several still open questions. Nowadays, thanks to the most modern telescopes and instruments, we are able to observe and analyse many physical and chemical processes…
There are obvious and direct ways in which the presence of binary companions may affect activity in OB stars through tidal interactions. In this review, however, I consider a more fundamental role for multiplicity and explore claims that…
We present high resolution spectro-astrometry of a sample of 28 Herbig Ae/Be and 3 F-type pre-main sequence stars. The spectro-astrometry is shown from both empirical and simulated data to be capable of detecting binary companions that are…
In the present review we discuss the past and present status of the interacting OB-type binary frequency. We critically examine the popular idea that Be-stars and supergiant sgB[e] stars are binary evolutionary products. The effects of…
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…
A detailed understanding of the physics of star and planet formation requires study of individual objects as well as statistical assessment of global properties and evolutionary trends. Observational investigations of circumstellar material…