Related papers: IRAS\,11472-0800: an extremely depleted pulsating …

Post-asymptotic giant branch stars (post-AGB) in binary systems, with typical orbital periods between ~100 to ~1000 days, result from a poorly understood interaction that terminates their precursory AGB phase. The majority of these binaries…

Binary post-asymptotic giant branch (post-AGB) stars have orbital periods in the range of 100--2500 days in eccentric orbits. They are surrounded by circumbinary dusty discs. They are the immediate result of unconstrained binary interaction…

We present ISAAC spectroscopy and ISAAC, UKIDSS and Spitzer Space Telescope broad-band photometry of SDSS J1228+1040 -- a white dwarf for which evidence of a gaseous metal-rich circumstellar disk has previously been found from optical…

Circumbinary disks have been hypothesized to exist around a number of binary post-AGB stars. Although most of the circumbinary disks have been inferred through the near IR excess, a few of them are strong emitters of molecular emission.…

The quest for quiet or dormant black holes has been ongoing since several decades. Ellipsoidal variables possibly indicate the existence of a very high-mass invisible companion and are thought to be one of the best ways to find such dormant…

Field star BD+20 307 is the dustiest known main sequence star, based on the fraction of its bolometric luminosity, 4%, that is emitted at infrared wavelengths. The particles that carry this large IR luminosity are unusually warm, comparable…

IRAS 16279-4757 belongs to a group of post-AGB stars showing both PAH bands and crystalline silicates. We present mid-infrared images, that resolve the object for the first time. The morphology is similar to that of the `Red Rectangle' (HD…

We present an eccentric precessing gas disk model designed to study the variable circumstellar absorption features detected for WD 1145+017, a metal polluted white dwarf with an actively disintegrating asteroid around it. This model,…

We present high spatial resolution Submillimeter Array observations and supplementary single-dish photometry of the molecular gas and dust around IRAS 04158+2805, a young source with spectral type M5-M6 in the Taurus star-forming region. A…

Highly accreting quasars are quite luminous in the X-ray and optical regimes. While, they tend to become radio quiet and have optically thin radio spectra. Among the known quasars, IRAS F11119+3257 is a supercritical accretion source…

The evolutionary state of the 198 day eclipsing binary BM Cas is examined using spectra that cover five orbital cycles. Radial velocities measured from SiII 6347 and SiII 6371 track the motion of the primary, and a mass function is found…

Among the competing evolution theories for subdwarf-B (sdB) stars is the binary evolution scenario. EC~20117-4014 (=V4640~Sgr) is a spectroscopic binary system consisting of a pulsating sdB star and a late F main-sequence companion…

We present near-IR spectroscopy and HST imaging of EROJ164023, an Extremely Red Object (ERO) with R-K=5.9 at z=1.05. EROJ164023 is a disk galaxy, with an optical/IR spectral energy distribution which is strongly reddened by dust…

Previous studies have shown that many post-AGB stars with dusty disks are associated with single-lined binary stars. To verify the binarity hypothesis on a larger sample, we started a high-resolution spectral monitoring of about 40 field…

We re-examine the nature of NGC2024-IRS2 in light of the recent discovery of the late O-type star, IRS2b, located 5 arcsec from IRS2. Using L-band spectroscopy, we set a lower limit of Av = 27.0 mag on the visual extinction towards IRS2.…

We report high-resolution spectroscopic observations of WD 1145+017 -- a white dwarf that recently has been found to be transitted by multiple asteroid-sized objects within its tidal radius. We have discovered numerous circumstellar…

We present AKARI/IRC observations of a sample of six extremely red IRAS sources, of which three are variable OH/IR stars and the rest are early post-AGB stars. The OH/IR stars show a red continuum with the expected strong 10 micron silicate…

We present in this paper a study on the peculiar supergiant HD172481. Its spectral type (F2Ia), high galactic latitude (b=-10.37), circumstellar dust, high radial velocity and moderate metal deficiency ([Fe/H]=-0.55) confirm the post-AGB…

We present here new observations of the eccentric debris ring surrounding the Gyr-old solar-type star HD 202628: at millimeter wavelengths with ALMA, at far-infrared wavelengths with \textit{Herschel}, and in scattered light with…

The vast majority of the most iron-poor stars in the Galaxy exhibit a strong carbon enhancement, with C/H ratios only about two orders of magnitude below solar. This unusual chemical composition likely reflects the properties of the gas…