Related papers: Radial Velocity Evidence for a Post-Mass-Transfer …
We present the discovery of a binary system containing a white dwarf candidate using data from the LAMOST. Our analysis of the radial velocity data allowed us to determine an orbital period of approximately 0.953 days and a mass function of…
We have obtained FUSE spectra of sigma Her, a nearby binary system, with a main sequence primary, that has a Vega-like infrared excess. We observe absorption in the excited fine structure lines C II* at 1037 A, N II* at 1085 A, and N II**…
We report our spectroscopic observations of stars belonging to the young nearby group known as the TW Hydrae association, as well as of a number of potential members of the association identified in kinematic and X-ray surveys. Multiple…
After the first detection of its binary nature, the spectroscopic monitoring of the non-thermal radio emitter Cyg OB2 #9 (P=2.4yrs) has continued, doubling the number of available spectra of the star. Since the discovery paper of 2008, a…
The presence of disks and outflows is widespread among post-AGB binaries. In the first paper of this series, a surprisingly large fraction of optical light was found to be resolved in the 89 Her post-AGB system. The data showed this flux to…
Based on high-resolution UVES spectra we found that the radial velocity (RV) dispersion of nine of twelve known young bona fide and candidate brown dwarfs in the Cha I dark cloud is 2.0 km/s, i.e. significantly smaller than the RV…
High-mass multiples might form via fragmentation of self-gravitational disks or alternative scenarios such as disk-assisted capture. However, only few observational constraints exist on the architecture and disk structure of high-mass…
We report on a search for evidence of binarity in Far-Ultraviolet Spectroscopic Explorer (FUSE) observations of DAO white dwarfs. Spectra recorded by FUSE are built up from a number of separate exposures. Observation of changes in the…
We present a spectroscopic analysis of MWC 314, a luminous blue variable (LBV) candidate with an extended bipolar nebula. The detailed spectroscopic variability is investigated to determine if MWC 314 is a massive binary system with a…
A sample of 14 pre-main sequence visual binary systems in southern star-forming regions were imaged at 2 um with the Keck I telescope to search for tertiary companions, scattered-light disks, and compact nebulae at linear scales of 5-100…
We report an in-depth study of the F8-type star HD 166191, identified in an ongoing survey for stars exhibiting infrared emission above their expected photospheres in the Wide-field Infrared Survey Explorer all-sky catalog. The fractional…
We present millimeter interferometric observations of the young stellar object SVS13 in NCG1333 in the N2H+(1-0) line and at 1.4 and 3mm dust continuum, using the IRAM Plateau de Bure interferometer. The results are complemented by infrared…
Radial velocity monitoring has revealed the presence of moving broad emission lines in some quasars, potentially indicating the presence of a sub-parsec binary system. Phase-referenced, near-infrared interferometric observations could map…
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 narrow-band optical images, VLA-A 3.6 cm continuum and H92alpha emission line data and high resolution long-slit [N II] spectra of Hu 2-1. The formation of Hu 2-1 appears dominated by anisotropic mass ejection during the late AGB…
We report $I$-band photometric observations of the radio-detected M9.5 dwarf BRI 0021-0214, obtained with the Galway Ultra Fast Imager (GUFI) on the 1.8m Vatican Advanced Technology Telescope VATT at Mt. Graham International Observatory,…
We present HST/WFPC2 observations of a sample of 134 ultra-cool objects (spectral types later than M7) coming from the DENIS, 2MASS and SDSS surveys, with distances estimated to range from 7 pc to 105 pc. Fifteen new ultra-cool binary…
We investigate the X-ray variability of the supergiant X-ray binary 4U 1907+09 using the new NuSTAR observation of 2024. The source had a relatively stable flux level during previous NuSTAR observations, but the flux varied significantly…
We present the results of a Spitzer photometric investigation into the IR excesses of close binary systems. In a sample of 10 objects, excesses in IRAC and MIPS24 bands implying the presence of warm dust are found for 3. For 2 objects we do…
We present high resolution echelle spectra taken during four observing runs from 1999 to 2001 of the recently X-ray/EUV selected chromospherically active binary BK Psc (2RE J0039+103). Our observations confirm the single-lined spectroscopic…