Related papers: Gaia22ayj: outburst from a deeply eclipsing 9.36-m…

We present infrared JHK photometry of the cataclysmic variable SDSS J123813.73-033933.0 (SDSS1238)and analyze it along with optical spectroscopy, demonstrating that the binary system is most probably comprised of a massive white dwarf with…

We present the results of a two and a half year optical photometric monitoring programme covering 16 AM CVn binaries using the Liverpool Telescope on La Palma. We detected outbursts in seven systems, one of which (SDSS J0129) was seen in…

Double-close-binary quadruples (2+2 systems) are hierarchical systems of four stars where two short-period binary systems move around their common center of mass on a wider orbit. Using Gaia Early Data Release 3, we search for comoving…

The orbital period of the recurrent nova U Sco has been observed to decrease during the 1999 outburst. In an outburst mass is ejected from the surface of the white dwarf. The separation of the binary system widens and the orbital period…

We report on a 63ks Chandra observation of the X-ray transient Swift J195509.6+261406 discovered as the afterglow of what was first believed to be a long duration Gamma-Ray Burst (GRB 070610). The outburst of this source was characterized…

AM CVn binaries are a class of ultracompact, hydrogen-deficient binaries, each consisting of a white dwarf accreting helium-dominated material from a degenerate or semi-degenerate donor star. Of the 56 known systems, only Gaia14aae…

Hot subdwarf binaries with white dwarf companions with orbital periods of less than two hours are progenitor candidates for massive single white dwarfs as well as a variety of thermonuclear explosions. Our aim is to determine the binary…

The March 2011 outburst of the poorly-studied cataclysmic variable NSV 1436 offered an opportunity to decide between dwarf nova and recurrent nova classifications. We use seven daily observations in the X-ray and UV by the Swift satellite,…

We revisit various sets of published results from X-ray and optical studies of the Galactic black hole (BH) candidate MAXI J0637-430, which went into outburst in 2019. Combining the previously reported values of peak outburst luminosity,…

We report observations using the Swift/XRT, NuSTAR, and Chandra X-ray telescopes of the transient X-ray source CXOGC J174540.0-290005, during its 2013 outburst. Due to its location in the field of multiple observing campaigns targeting Sgr…

We present the Apache Point Observatory BG40 broadband and simultaneous Gemini $r$-band and $i$-band high-speed follow-up photometry observations and analysis of the 40.5 minute period eclipsing detached double-degenerate binary SDSS…

We report on the discovery of the shortest period binary comprising a hot subdwarf star (CD-30 11223, GALEX J1411-3053) and a massive unseen companion. Photometric data from the All Sky Automated Survey show ellipsoidal variations of the…

In a search for eclipsing white dwarfs using the Zwicky Transient Facility lightcurves, we identified a deep eclipsing white dwarf with a dark, substellar companion. The lack of an infrared excess and an orbital period of 10 hours made this…

Several brief outbursts were detected in the dwarf nova V1316 Cyg during 2005. These events have an average amplitude of 1.4 magnitude and a duration of <1 to 2 days. Whilst no outburst period could be confirmed, the shortest period between…

Swift J1753.5-0127 (J1753) is a candidate black hole low-mass X-ray binary (BH-LMXB) that was discovered in outburst in May 2005. It remained in outburst for $\sim12$ years, exhibiting a wide range of variability on various timescales,…

We report on the coherent timing analysis of the 182 Hz accreting millisecond X-ray pulsar Swift J1756.9$-$2508 during its 2018 outburst as observed with the Neutron Star Interior Composition Explorer (NICER). Combining our NICER…

We report the discovery of ZTF J2020+5033, a high-mass brown dwarf (BD) transiting a low-mass star with an orbital period of 1.90 hours. Phase-resolved spectroscopy, optical and infrared light curves, and precise astrometry from Gaia allow…

WZ Sge-type dwarf novae form one of the most intriguing classes of compact accreting binaries. They are recognized as the most evolved population of hydrogen-rich cataclysmic variables. Yet they exhibit energetic disk-powered outbursts with…

RX J0806+15 has recently been identified as the binary system with the shortest known orbital period. We present a series of observations of RX J0806+15 including new optical observations taken one month apart. Using these observations and…

We present optical photometry and spectroscopy of the X-ray transient XTE J1859+226, obtained during outburst and its subsequent decay to quiescence. Both the X-ray and optical properties are very similar to those of well-studied black hole…