Related papers: A Parameter Study of Classical Be Star Disk Models…
We investigate the structure of the innermost region of three circumstellar disks around pre-main sequence stars HD 142666, AS 205 N, and AS 205 S. We determine the inner radii of the dust disks and, in particular, search for transition…
High spectral-resolution Br-gamma VLTI/AMBER observations of classical Be stars reveal complex visibility, phase, and closure phase profiles, which were not seen in previous lower-resolution data. They present new challenges for the…
This paper presents a detailed statistical determination of the equatorial rotation rates of classical Be stars. The rapid rotation of Be stars is likely to be linked to the ejection of gas that forms dense circumstellar disks. The physical…
We performed the slitless spectroscopic survey to identify Classical (CBe) stars in open clusters older than 100 Myr. Observing a sample of 71 open clusters, we identified 13 CBe stars in 11 open clusters, one of, which (TYC 2679-432-1) is…
Z CMa is a complex binary system, composed of a Herbig Be and an FU Ori star. The Herbig star is surrounded by a dust cocoon of variable geometry, and the whole system is surrounded by an infalling envelope. Previous spectropolarimetric…
The tidal interaction of a Be star with a binary companion forms two spiral arms that cause orbital modulation of the Be disc structure. The aim of this work is to identify observables in which this modulation is apparent. The structure of…
We recently discovered a large number of highly active Be stars in the open cluster NGC 3766, making it an excellent location to study the formation mechanism of Be star disks. To explore whether similar disk appearances and/or…
We present the first part of a spectroscopic and polarimetric study on a sample of 58 Be stars that have been measured since 1998. The aim of the study is to understand the timescales of disk variability, formation and dissipation as a…
Classical Ae (CAe) stars are main sequence, A-type stars with H{\alpha} emission but no signature of dust. They are thought to be the cool extension of the classical Be stars to lower masses. Recent surveys based on H{\alpha} spectroscopy…
We report the results of a study of the intermediate and high mass stars in the young, rich star-forming complex IC 1805, based on a combination of optical, near-infrared, and mid-infrared photometry, and classification spectra. These data…
(Abriged) We present the results of millimeter observations and a suitable chemical and radiative transfer model of the AB Aur (HD 31293) circumstellar disk and surrounding envelope. The integral molecular content of this system is studied…
An analysis of solid-state features in infrared spectra of 46 Herbig Ae/Be stars is presented. The presence of solid-state emission bands is compared to other indicators of circumstellar material, such as Halpha emission, optical…
We present self-consistent solutions for the disk structure of classical Be stars. Our disk model is hydrostatically supported in the vertical direction and the radial structure is governed by viscosity ($\alpha$-disks). We perform…
Using the 3-telescope IOTA interferometer on Mt. Hopkins, we report results from the first near-infrared (lambda=1.65 mu) closure-phase survey of Young Stellar Objects (YSOs). These closure phases allow us to unambiguously detect departures…
In a recent study, Banerjee et al. (2021) produced an atlas of all major emission lines found in a large sample of 115 Galactic field Be stars using the 2-m Himalayan Chandra Telescope (HCT) facility located at Ladakh, India. This paper…
We use the three-dimensional Monte Carlo radiative transfer code HDUST to model Be stars where the disc is tilted from the equatorial plane of the star. We compute 128 models across 4 spectral types, B0, B2, B5 and B8, tilting the disc by…
In Wisniewski et al. 2010, paper I, we analyzed 15 years of spectroscopic and spectropolarimetric data from the Ritter and Pine Bluff Observatories of 2 Be stars, 60 Cygni and {\pi} Aquarii, when a transition from Be to B star occurred.…
In this paper we study the evolution of viscous and radiative circumstellar disks under the influence of a companion star. We focus on the eccentric {\gamma} Cephei and {\alpha} Centauri system as examples and compare the disk quantities…
Omicron Aquarii is late-type, Be shell star with a stable and nearly symmetric H$\alpha$ emission line. We combine H$\alpha$ interferometric observations obtained with the Navy Precision Optical Interferometer (NPOI) covering 2007 through…
The B-W method is used to determine the distance of Cepheids and consists in combining the angular size variations of the star, as derived from infrared surface-brightness relations or interferometry, with its linear size variation, as…