Related papers: Spectroscopy of close visual binary components of …
We present the first results from an ongoing survey for multiplicity among the bright stars using the Navy Precision Optical Interferometer (NPOI). We first present a summary of NPOI observations of known multiple systems, including the…
Using data mining techniques applied on emission line characteristics of Be stars spectra we attempted to find new Be stars candidates in SDSS SEGUE survey. The mid-resolution spectra of confirmed Be stars obtained from VO-compatible…
Stars stripped of their envelope through interaction in a binary are generally not considered when accounting for ionizing radiation from stellar populations, despite the expectation that stripped stars emit hard ionizing radiation, form…
We have discovered a large number of circular and elliptical shells at 24 microns around luminous central sources with the MIPS instrument on-board the Spitzer Space Telescope. Our archival follow-up effort has revealed 90% of these…
CTA~1 is a composite supernova remnant featuring a shell structure and an inner Pulsar Wind Nebula. The shell is visible in the radio band, while Fermi has detected the radio-quiet pulsar PSR J0007+7303 at its core. Gamma-ray detectors such…
The southern emission-line star HD 144432 has received considerable attention due to its relative brightness (V ~ 8.17), its late spectral type (late A-type or perhaps early F) and its relative isolation from a bona-fide active star…
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…
A popular model for the circumstellar disks of Be stars is that of a geometrically thin disk with a density in the equatorial plane that drops as a power law of distance from the star. It is usually assumed that the vertical structure of…
Spatially resolved observations of the Sun and the astronomical sample size of stellar bodies are the respective key strengths of solar and stellar observations. However, the large difference in object brightness between the Sun and other…
We present high angular resolution imaging observations of 517 host stars of TESS exoplanet candidates using the `Alopeke and Zorro speckle cameras at Gemini North and South. The sample consists mainly of bright F, G, K stars at distances…
This paper describes the aims, objectives and first results of the observational program for the study of distant core-collapse supernovae (SNe) with redshifts z < 0.3. This work is done within the framework of an international cooperation…
We report the identification of SH $\Delta v=1$ ro-vibrational lines in the published high-resolution infrared spectrum of the S-type star, R And. This is the first astronomical detection of this molecule. The lines show inverse P-Cygni…
Samples of reliably identified halo wide binaries are scarce. If reasonably free from selection effects and with a small degree of contamination by chance alignments, these wide binaries become a powerful dynamical tool, having provided one…
The main goal of this work is to perform a detailed study of the optical variability of the Be/X-ray binary SAX J2239.3+6116. We obtained multi-colour BVRI photometry and polarimetry and 4000-7000 A spectroscopy. The optical counterpart to…
This work analyzes four Sun-like double-lined spectroscopic binary (SB2) systems by combining visual and spectroscopic observational data with Al-Wardat's atmospheric modeling method to accurately determine their fundamental parameters. For…
Radial-velocity measurements and sine-curve fits to the orbital radial velocity variations are presented for the last eight close binary systems analyzed the same way as in the previous papers of this series: QX And, DY Cet, MR Del, HI Dra,…
We present the first VLTI/MIDI observations of the Be star Alpha Ara, showing a nearly unresolved circumstellar disk in the N band. The interferometric measurements made use of the UT1 and UT3 telescopes. The projected baselines were 102…
We present the highlights from our recent study of 22 local (z$<$0.025) type-1 LINERs from the Palomar Survey, on the basis of optical long-slit spectroscopic observations taken with TWIN/CAHA, ALFOSC/NOT and HST/STIS (Cazzoli et al. 2018).…
The results of speckle interferometric observations of 115 metal-poor stars [m/H]<-1 within 250 pc from the Sun and with proper motions mu <= 0.2"/yr, made with the 6-m telescope of the Special Astrophysical Observatory of the Russian…
The aim of this article is to demonstrate the useful role that can be played by spectropolarimetric observations of young and evolved emission line stars that analyse the linearly polarized component in their spectra. At the time of…