Related papers: Ultraviolet Study of the Active Interacting Binary…

We assess archival high-energy data for key stars on the Habitable Worlds Observatory (HWO) Target Stars and Systems 2025 list, as stellar radiation is critical to shaping and interpreting planetary atmospheres. Using a sample of 98 nearby…

In this paper we present multi-epoch observations of the pre-main sequence binary HK Ori. These data have been drawn from the EXPORT database and are complemented by high quality spectro-astrometric data of the system. The spectroscopic…

We present Hubble Space Telescope imaging and spectroscopy of HD 217411, a G3 V star associated with the extreme ultraviolet excess source (EUV 2RE J2300-07.0). This star is revealed to be a triple system with a G 3V primary (HD 217411 A)…

Using an Extreme Ultraviolet Explorer (EUVE) spectrum, we confirm the identification of a white dwarf companion to the B9.5V star 16 Dra (HD150100), and constrain its surface temperature to lie between 29,000K and 35,000K. This is the third…

We present the most comprehensive near-ultraviolet (NUV: 2550-3255 Angstrom) activity record to date for the Alpha Centauri AB system, combining archival IUE and HST observations spanning nearly five decades with new high-cadence CUTE…

We present far-ultraviolet (905 -- 1182 A), time-series spectroscopy of the eclipsing, novalike cataclysmic variable, UX UMa, acquired with FUSE. The time-averaged spectrum is complex and is dominated by overlapping spectral features. The…

There is growing evidence that some Be stars were spun up through mass transfer in a close binary system, leaving the former mass donor star as a hot, stripped-down object. There are five known cases of Be stars with hot subdwarf (sdO)…

Context. HD 85567 is an enigmatic object exhibiting the B[e] phenomenon, i.e. an infrared excess and forbidden emission lines in the optical. The object's evolutionary status is uncertain and there are conflicting claims that it is either a…

We report 3.6 cm continuum observations taken with the Very Large Array (VLA) of the young binary system UY Aur. The binary consists of a T Tauri star, UY Aur A, and a so-called ``infrared companion'' (IRC), UY Aur B, separated by 0.''89.…

We used archival International Ultraviolet Explorer (IUE) high-dispersion, short wavelength spectra data to search for evidence of the spectra of hot subdwarf companions of six rapidly rotating Be stars in binary systems. We searched for…

Interacting binaries consist of a secondary star which fills or is very close to filling its Roche lobe, resulting in accretion onto the primary star, which is often, but not always, a compact object. In many cases, the primary star,…

We present an infrared imaging study of the low-mass pre-main sequence binary system Haro 6-10. This system is one of a handful in which the optically-visible primary has the characteristics of a normal T Tauri star, while the secondary is…

We review the results of the 1988 multi-wavelength campaign on the late-type eclipsing binary YY Geminorum. Observations include: broad-band optical and near infra-red photometry, simultaneous optical and ultraviolet (IUE) spectroscopy,…

RR Lyrae pulsating stars have been extensively used as tracers of old stellar populations for the purpose of determining the ages of galaxies, and as tools to measure distances to nearby galaxies. There was accordingly considerable interest…

Recent observational work has indicated that mechanisms for accretion and outflow in Herbig Ae/Be star-disk systems may differ from magnetospheric accretion (MA) as it is thought to occur in T Tauri star-disk systems. In this work, we…

We present a detailed NIR/optical/UV study of the transient low mass X-ray binary 1RXS J180408.9-342058 performed during its 2015 outburst, aimed at determining the nature of its companion star. We obtained three optical spectra at the 2.1…

The first V Rc Ic bands light curves of MQ UMa are presented and analyzed using the Wilson-Devinney (W-D) program. It is discovered that MQ UMa is an A-subtype contact binary with a high fill-out (f=82 %) and a low mass ratio (q = 0:195),…

We present time-series spectroscopy and photometry of Gaia DR2 6097540197980557440, a new deeply-eclipsing hot subdwarf B (sdB) + M dwarf (dM) binary. We discovered this object during the course of the Eclipsing Reflection Effect Binaries…

Eta Carinae, the closest, active, massive binary containing a highly unstable LBV, exhibits expanding, compressed wind shells, seen in emission, that are spatially and spectrally resolved by \hst/\stis. Starting in June 2009, these…

TU Tau (= HD 38218 = HIP 27135) is a binary system consisting of a C-N carbon star primary and an A-type secondary. We report on new photometry and spectroscopy which tracked the recent disappearance of the A-star secondary. The dimming of…