Related papers: No longer impossible: the self-lensing binary KIC …

Double white dwarf systems are of great astrophysical importance in the field of gravitational wave and Type Ia supernova. While the binary fraction of CO core white dwarf is about a few percents, the extremely low mass white dwarfs are all…

The Laser Interferometer Space Antenna (LISA) will detect and characterize $\sim10^4$ Galactic Binaries consisting predominantly of two White Dwarfs (WD). An interesting prospect within this population is a third object--another WD star, a…

We present 594 radial velocity measurements for 71 white dwarfs obtained during our search for binary white dwarfs and not reported elsewhere. We identify three excellent candidate binaries, which require further observations to confirm our…

The purpose of this work is to extend a sample of accurately modeled, benchmark-grade eclipsing binaries with accurately determined masses and radii. We select four "well-behaved" Kepler binaries, KIC2306740, KIC4076952, KIC5193386 and…

We report the discovery of two new low-mass, thermally bloated, hot white dwarfs among the Kepler sample of eclipsing binaries. These are KIC 9164561 and KIC 10727668 with orbital periods of 1.2670 and 2.3058 days, respectively. The current…

KIC 2856960 is a star in the Kepler field which was observed by Kepler for 4 years. It shows the primary and secondary eclipses of a close binary of 0.258d as well as complex dipping events that last for about 1.5d at a time and recur on a…

We have revisited the sdB+K-star long-period binary PG 1018-047 based on 20 new high-resolution VLT/UVES spectra that provided regular coverage over a period of more than 26 months. We refine the period and establish that the orbit is…

Self-lensing (SL) represents a powerful technique for detecting compact objects in binary systems through gravitational microlensing effects, when a compact companion transits in front of its luminous partner. We present the first…

Motivated by the discovery of a handful of pulsating, extremely low mass white dwarfs (ELM WDs, mass $M \lesssim 0.17\, M_\odot$) which likely have WD companions, this paper discusses binary formation models for these systems. Formation of…

We carried out light curve solutions of the ultrashort-period binaries with MS components observed by $Kepler$. All six targets turned out almost in thermal contact with contact or slightly overcontact configurations. Two of them, KID…

The lack of RR Lyr stars in binary systems is an atypical fact when we compared it to other classes of variables. Therefore, it has become a challenge for observers to detect an RR Lyr variable in a binary system. The RR Lyr variable KIC…

Among the 28,000 targeted stars in K2 Field 10 is the white dwarf WD 1202-024 (EPIC 201283111), first noted in the SDSS survey (SDSS 120515.80-024222.7). We have found that this hot white dwarf (Teff = 22,640 K) is in a very close orbit (P…

Extremely low mass white dwarfs are very rare objects likely formed in compact binary systems. We present MMT optical spectroscopy of 42 low mass white dwarf candidates serendipitously discovered in a survey for hypervelocity B-type stars.…

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…

We present the final sample of 98 detached double white dwarf (WD) binaries found in the Extremely Low Mass (ELM) Survey, a spectroscopic survey targeting <0.3 Msun He-core WDs completed in the Sloan Digital Sky Survey footprint. Over the…

KIC 9532219 is a W UMa-type eclipsing binary with an orbital period of 0.1981549 d that is below the short-period limit ($\sim$0.22 d) of the period distribution for contact binaries. The {\it Kepler} light curve of the system exhibits…

White dwarfs with a F, G or K type companion represent the last common ancestor for a plethora of exotic systems throughout the galaxy, though to this point very few of them have been fully characterised in terms of orbital period and…

We report on the discovery of Swift J011511.0-725611, a rare Be X-ray binary system (BeXRB) with a White Dwarf (WD) compact object, in the Small Magellanic Cloud (SMC) by S-CUBED, a weekly X-ray/UV survey of the SMC by the Neil Gehrels…

Blue straggler stars (BSSs) are formed through mass transfer or mergers in binaries. The recent detections of white dwarf (WD) companions to BSSs in M67 suggested a mass transfer pathway of formation. In search of a close companion to five…

Binary millisecond pulsars with a massive white dwarf (WD) companion are intermediate-mass binary pulsars (IMBPs). They are formed via the Case BB Roche-lobe overflow evolution channel if they are in compact orbits with an orbital period of…