相关论文: A Spectroscopic Orbit for the late-type Be star $\…

The Be stars display variable optical emission lines originating in the circumstellar disc. Here we analyse high resolution spectroscopic observations of Be stars and the distance between the peaks of H-alpha, H-beta, and H-gamma emission…

Binarity is often invoked to explain peculiarities that can not be explained by the standard theory of stellar evolution. Detecting orbital motion via the Doppler effect is the best method to test binarity when direct imaging is not…

We present precise stellar radial velocity measurements for the K giant star Beta Gem spanning over 25 years. These data show that the long period low amplitude radial velocity variations found by Hatzes & Cochran (1993) are long-lived and…

We performed the optical spectroscopy of 16 classical Be stars in 11 open clusters older than 100 Myr. Ours is the first spectroscopic study of classical Be stars in open clusters older than 100 Myr. We found that the H alpha emission…

(Abridged) Classical Be stars occasionally transition from having a gaseous circumstellar disk (''Be phase'') to a state in which all observational evidence for the presence of these disks disappears (''normal B-star phase''). We present…

We present new spectroscopic observations of the Be/black hole binary MWC 656 obtained during the period 2015 - 2021. We measure the equivalent width of H$\alpha$ (EW$_\alpha$), H$\beta$ ($EW_\beta$), and the distance between the peaks of…

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…

We present the spectroscopic and photometric observations on the Be/X-ray binary RX~J0440.9+4431 from 2001 to 2014. The short-term and long-term variability of the H$\alpha$ line profile indicates that one-armed global oscillations existed…

We recently reported on the detection of a possible planetary-mass companion to Beta Pictoris at a projected separation of 8 AU from the star, using data taken in November 2003 with NaCo, the adaptive-optics system installed on the Very…

We present a near-IR spectroscopic analysis of the intriguing DO white dwarf RE J0503-285. The IR spectrum fails to reveal evidence of the presence of a spatially unresolved, cool, late-type companion. Hence we have placed an approximate…

The light curve of a blue variable in the MACHO LMC database (FTS ID 78.5979.72) appeared nearly unvarying for ~4 years (quasi-flat segment) but then rapidly changed to become periodic with noisy minima for the remaining 4 years (periodic…

We present the results of the interferometric observations of the circumstellar disk surrounding MWC 297 in the continuum at 230 GHz (1.3 mm) and in the (J=2-1) rotational transitions of $^{12}$CO,$^{13}$CO and C$^{18}$O using the…

Characterizing the physical properties and compositions of circumplanetary disks can provide important insights into the formation of giant planets and satellites. We report ALMA 0.88 mm (Band 7) continuum observations of six planetary-mass…

The viscous decretion disk (VDD) model is able to explain most of the currently observable properties of the circumstellar disks of Be stars. However, more stringent tests, focusing on reproducing multitechnique observations of individual…

Stars are generally spherical, yet their gaseous envelopes often appear non-spherical when ejected near the end of their lives. This quirk is most notable during the planetary nebula phase when these envelopes become ionized. Interactions…

Long-baseline interferometric observations obtained with the Navy Prototype Optical Interferometer of the H-alpha-emitting envelopes of the Be stars eta Tauri and beta Canis Minoris are presented. For compatibility with the previously…

We study the possibility that Type Ia supernovae might be produced by binary systems where the companion of the exploding white dwarf is an M-dwarf star. Such companion would appear as a runaway star, retaining its pre-explosion orbital…

The majority of massive classical Be stars are thought to be binary interactions products. Their rapid rotation and often strong, variable, and emission-line dominated spectrum, make spectroscopic analysis challenging. Hence, robust binary…

We present a mini-survey of Galactic B[e] stars mainly undertaken with the Large Binocular Telescope (LBT). B[e] stars show morphological features with hydrogen emission lines and an infrared excess, attributed to warm circumstellar dust.…

Optical and near-infrared observations are compiled for the three gamma-ray binaries hosting Be stars: PSR B1259-63, LSI+61 303, and HESS J0632+057. The emissions from the Be disk are considered to vary according to the changes in its…