相关论文: The binary fraction and mass-ratio of Be and B sta…
We present multiple epochs of H-alpha spectroscopy for 47 members of the open cluster NGC 3766 to investigate the long term variability of its Be stars. Sixteen of the stars in this sample are Be stars, including one new discovery. Of…
The purpose of this work is to review the observational properties of Be/X-ray binaries. The open questions in Be/X-ray binaries include those related to the Be star companion, that is, the so-called "Be phenomenon", such as, timescales…
Rapidly rotating classical OBe stars have been proposed as the products of binary interactions, and the fraction of Be stars with compact companions implies that at least some are. However, to constrain the interaction physics spinning up…
In this article, I examine several observational trends regarding protoplanetary disks, debris disks and exoplanets in binary systems in an attempt to constrain the physical mechanisms of planet formation in such a context. Binaries wider…
The dynamical influence of binary companions is expected to profoundly influence planetary systems. However, the difficulty of identifying planets in binary systems has left the magnitude of this effect uncertain; despite numerous…
Recent observational studies suggest that Be stars most likely are formed through the process of mass transfer in binary systems. In view of the wide consensus that the origin of the magnetic field in stars with radiative envelopes involves…
Binary stars and higher-order multiple systems are an ubiquitous outcome of star formation, especially as the system mass increases. The companion mass-ratio distribution is a unique probe into the conditions of the collapsing cloud core…
Spectroscopic multiplicity surveys of O stars in young clusters and OB associations have revealed that a large portion ($\sim$ 70%) of these massive stars (M$_{i}$ $\gt$ 15 $M_{\odot}$) belong to close and short-period binaries (physical…
In the past decade, a consensus has emerged regarding the nature of classical Be stars: They are very rapidly rotating main sequence B stars, which, through a still unknown, but increasingly constrained process, form an outwardly diffusing…
Stellar multiplicity is believed to influence planetary formation and evolution, although the precise nature and extent of this role remain ambiguous. We present a study aimed at testing the role of stellar multiplicity in the formation…
We report about an ongoing photometric and spectroscopic monitoring survey of about 250 O- and 540 B-type stars in the southern Milky Way with the aim to determine the fraction of close binary systems as a function of mass and to determine…
To study the variability of the 523 B and Be stars observed in the Magellanic clouds with the VLT-FLAMES, we cross-matched the stars of our sample with the photometric database MACHO, which provides for each star an 8 years lightcurve. We…
The typical product of the star formation process is a binary star. Binaries have provided the first dynamical measures of the masses of pre-main-sequence (PMS) stars, providing support for the calibrations of PMS evolutionary tracks.…
The presence of a stellar companion closer than ~100 AU is likely to affect planet formation and evolution. Yet, the precise effects and their actual impact on planet occurrence are still debated. To bring observational constraints, we have…
We present HST/ACS observations of 19 nearby M subdwarfs in a search for binary systems. Other than the wide common proper motion pair LHS 2140/2139, none of our sdM and esdM targets are found to be binaries. Our survey is sensitive to…
Previous studies have observed significant photometric differences between non-emission B-type and classical Be stars, however the precise mechanism responsible for these differences is unclear. This study combines the Bright Star Catalogue…
We present a high spatial resolution UV to NIR survey of 44 young binary stars in Taurus with separations of 10-1000 AU. The primary results include: (1) The relative ages of binary star components are more similar than the relative ages of…
The circumstellar disk density distributions for a sample of 63 Be southern stars from the BeSOS survey were found by modelling their H$\alpha$ emission line profiles. These disk densities were used to compute disk masses and disk angular…
Roughly half of Solar-type planet hosts have stellar companions, so understanding how these binary companions affect the formation and evolution of planets is an important component to understanding planetary systems overall. Measuring the…
Be stars are rapidly rotating stars surrounded by a disc; however, the origin of these stars remains unclear. Mass and angular momentum transfer in close binaries account for the rapid rotation of a major fraction of Be stars, as supported…