Related papers: Dynamic masses for the close PG1159 binary SDSSJ21…

We report the discovery of SDSSJ1049+5103, an overdensity of resolved blue stars at (\alpha_{2000}, \delta_{2000}) = (162.343, 51.051). This object appears to be an old, metal-poor stellar system at a distance of 45 +/- 10 kpc, with a…

HD4539 (alias PG0044+097 or EPIC220641886) is a bright (V=10.2) long-period V1093 Her-type subdwarf B (sdB) pulsating star that was observed by the Kepler spacecraft in its secondary (K2) mission. We use the K2 light curve (78.7 days) to…

(Abridged). The cataclysmic binary V405 Peg, originally discovered as ROSAT Bright Source (RBS) 1955 (= 1RXS J230949.6+213523), shows a strong contribution from a late-type secondary star in its optical spectrum, which led Schwope et al. to…

LS 2883/PSR B1259-63 is a high mass, eccentric gamma-ray binary that has previously been observed to eject X-ray emitting material. We report the results of recent Chandra observations near binary apastron in which a new X-ray emitting…

We report the serendipitous discovery of the Sloan Digital Sky Survey star, SDSS J160043.6+074802.9 to be a very rapid pulsator. The variation is dominated by a frequency near 8380 microHz (period = 119.33 s) with a large amplitude (0.04…

We report follow-up XMM-Newton and ground-based optical observations of the unusual X-ray binary SDSS J102347.67+003841.2 (=FIRST J102347.6+003841), and a new candidate intermediate polar found in the Sloan Digital Sky Survey: SDSS…

The active galactic nucleus PKS 0301-243 (z=0.266) is a high-synchrotron-peaked BL Lac object that is detected at high energies (HE, 100 MeV < E < 100 GeV) by Fermi/LAT. This paper reports on the discovery of PKS 0301-243 at very high…

We report the detection of velocity variations in the pulsating sdB star, PG 1605+072. Oscillations are detected at the same frequencies found from photometry and have amplitudes of up to 14 km/s for H$\beta$. The strongest oscillation…

We report the results of a CGRO 3-week observation of the binary system containing the 47 ms pulsar PSR B1259-63 orbiting around a Be star companion in a very eccentric orbit. The PSR B1259-63 binary is a unique system for the study of the…

We have discovered that the brown dwarf WISEJ014656.66+423410.0 is a close binary (0.0875$\pm$0.0021 arcsec, 0.93$^{+0.12}_{-0.16}$ AU) from Keck laser guide star adaptive optics imaging. Our photometry for this system reveals that both…

We report a new compact galaxy, SDSS J122958.84+000138.0 (SDSS J1229+0001), which has unique morphological and stellar population properties that are rare in observations of the nearby universe. SDSS J1229+0001 has an $r$-band absolute…

EL CVn-type eclipsing binaries are composed of a massive A-type main-sequence primary star and a hotter B-type secondary star. This paper presents the time-series photometric and asteroseismic results of the EL CVn-type star 1SWASP…

We present the discovery of SDSS J135154.46-064309.0, a short-period variable observed using 30-minute cadence photometry in K2 Campaign 6. Follow-up spectroscopy and high-speed photometry support a classification as a new member of the…

We studied the radio spectrum of PSR B1259-63 in an unique binary with Be star LS 2883 and showed that the shape of the spectrum depends on the orbital phase. We proposed a qualitative model which explains this evolution. We considered two…

We present spectra of the pulsating sdB star KPD1930+2752 which confirm that this star is a binary. The radial velocities measured from the H-alpha and HeI6678 spectral lines vary sinusoidally with the same period (2h 17m) as the…

We have used Aperture Masking Interferometry and Adaptive Optics (AO) at the Palomar 200'' to obtain precise mass measurements of the binary M dwarf GJ 623. AO observations spread over 3 years combined with a decade of radial velocity…

We present observations of a new low-mass double-lined eclipsing binary system discovered using repeat observations of the celestial equator from the Sloan Digital Sky Survey II. Using near-infrared photometry and optical spectroscopy we…

It has been suggested that besides stellar companions, substellar objects in close orbits may be able to trigger mass loss in a common envelope phase and form hot subdwarfs. In an ongoing project we search for close substellar companions…

PSR J1910-5959A is a binary pulsar with a helium white dwarf companion located about 6 arcmin from the center of the globular cluster NGC6752. Based on 12 years of observations at the Parkes radio telescope, the relativistic Shapiro delay…

We present modeling of the long-term optical light curve and radial velocity curve of the binary stellar system CXOGBS J175553.2-281633, first detected in X-rays in the \textit{Chandra} Galactic Bulge Survey. We analyzed 7 years of optical…