Related papers: The first PG1159 close binary system

Theoretical models of low-mass stars continue to be discrepant with observations when used to examine the mass-radius relationship and other physical parameters of individual stars. High-resolution spectroscopy that leads to dynamical…

We report photometric observations of the eclipsing close binary CSS21055 (SDSS J141126+200911) that strongly suggest that the companion to the carbon-oxygen white dwarf is a brown dwarf with a mass between 0.030 and 0.074 Msun. The…

Using TESS 20-sec cadence data, we have discovered an unusual combination of pulsating stars in what we infer to be a binary system. The binary consists of a standard $\delta$ Scuti star with pulsations over the range 32-41 d$^{-1}$; this…

In a well-aimed search based on the recently published Gaia~DR2 radial velocity data and performed with the robotic TIGRE telescope, we have discovered 19 bright ($m_V<7.66$~mag) spectroscopic binary stars. We present the radial velocity…

To understand the nature of supernovae and neutron star (NS) formation, as well as binary stellar evolution and their interactions, it is important to probe the distribution of NS masses. Until now, all double NS (DNS) systems have been…

We present observations of fields containing eight recently discovered binary millisecond pulsars using the telescopes at MDM Observatory. Optical counterparts to four of these systems are detected, one of which, PSR J2214+3000, is a novel…

We present here the results of astrometric, photometric and spectroscopic observations leading to the determination of the orbit and dynamical masses of the binary L dwarf 2MASSW J0746425+2000321. High angular resolution observations spread…

We have used the radial velocity variations of two sdB stars previously reported to be binaries to establish their orbital periods. They are PG0940+068, (P=8.33d) and PG1247+554 (P=0.599d). The minimum masses of the unseen companions,…

NSVS 14256825 is the second sdOB + dM eclipsing binary systems with an orbital period of 2.65 hours. The special binary was reported to contain circumbinary planets or brown dwarfs by using the timing method. However, different results were…

The first multicolor observations and light curve solutions of the stars 1SWASP J130111.22+420214.0 and 1SWASP J231839.72+352848.2 are presented. The estimated physical parameters of 1SWASP J130111.22+420214.0 are $M_1=1.0M_{\odot}$,…

We present the results of a spectroscopic and photometric analysis of HD314884, a slowly pulsating B star (SPB) in a binary system with detected soft X-ray emission. We spectrally classify the B star as a B5V-B6V star with T$_{eff}$ =…

We report on the detection of the two shortest period non-interacting white dwarf binary systems. These systems, SDSS J143633.29+501026.8 and SDSS J105353.89+520031.0, were identified by searching for radial velocity variations in the…

Our discovery of 1SWASP J093010.78+533859.5 as a probable doubly eclipsing quadruple system containing a contact binary with P~0.23 d and a detached binary with P~1.31 d was announced in 2013. Subsequently Koo et al. confirmed the detached…

We report our investigation of 1SWASP J234401.81-212229.1, a variable with a 18461.6 s period. After identification in a 2011 search of the SuperWASP archive for main-sequence eclipsing binary candidates near the distribution's short-period…

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…

We report results of the first detailed spectral and temporal studies of the recently discovered Be/X-ray binary eRASSU J050810.4$-$660653 in LMC based on the data from the SRG/ART-XC, NuSTAR and Swift/XRT instruments obtained in December…

Tidally locked rotation is a frequently applied assumption that helps to measure masses of invisible compact companions in close binaries. The calculations of synchronization times are affected by large uncertainties in particular for stars…

We report a candidate centi-parsec supermassive black hole binary (SMBHB) in the radio-quiet quasar SDSS J0159+0105 at z=0.217. With a modified lomb-scargle code GLSdeDRW and the auto-correlation analysis ACF, we detect two significant (at…

PG 2131+066 is a composite-spectrum binary with a hot pulsating PG 1159-type pre-white dwarf and an early M-type main sequence star. Analysis of Whole Earth Telescope observations of the pulsating pre-white dwarf component provided an…

We report the discovery of PSR J1753-2240 in the Parkes Multibeam Pulsar Survey database. This 95-ms pulsar is in an eccentric binary system with a 13.6-day orbital period. Period derivative measurements imply a characteristic age in excess…