相关论文: Gaia19bxc: possible polar below the period minimum

We extended the $O-C$ diagram for V965 Cep with all currently available observations in the Johnson V filter and added unfiltered ones. The new, up-to-date $O-C$ diagram shows that the seeming period change previously revealed by the author…

We report the discovery and characterization of ZTF J0112+5827, a new magnetic cataclysmic variable with an orbital period of 80.9 minutes. ROSAT observations revealed X-ray emission with an average flux of $(68.4 \pm 15.7) \times 10^{-14}$…

The short period variable star MG1-688432 has been discovered to exhibit occasional extremely high energy optical outbursts as high as 10^31 joules. Outbursts are typically of several hours duration. These events are often highly…

Using improved, up-to-date stellar input physics tested against observations of low-mass stars and brown dwarfs we calculate the secular evolution of low-mass donor CVs, including those which form with a brown dwarf donor star. Our models…

We present here results of an optical spectroscopic study of a new Cataclysmic Variable SDSS J001856.93+345444.3. We demonstrate that the most probable value of the orbital period of the system is Porb = 0.6051 \pm 0.022 days (=14.5226…

We identify Gaia0007-1605AC as the first inner brown dwarf-white dwarf binary of a hierarchical triple system in which the outer component is another white dwarf (Gaia0007-1605B). From optical/near-infrared spectroscopy obtained at the Very…

We present optical photometric and spectroscopic observations of the faint-and-fast evolving type Iax SN 2019gsc, extending from the time of g-band maximum until about fifty days post maximum, when the object faded to an apparent r-band…

We report the discovery of a new Kepler first-overtone RR Lyrae pulsator, KIC 2831097. The pulsation shows large, 0.1 d amplitude, systematic phase variations that can be interpreted as light travel-time effect caused by orbital motion in a…

Ultracompact binary systems, consisting of two compact objects in an orbit $\lesssim 0.5 R_\odot$, should exhibit measurable rates of orbital period change ($\dot{P} \neq 0$) due to the emission of gravitational waves (GWs). Measurements of…

The second Gaia data release contains the identification of 147 535 low-mass ($\le 1.4 M_{\odot}$) rotational modulation variable candidates on (or close to) the main sequence, together with their rotation period and modulation amplitude.…

Photometric observations for the totally eclipsing binary system TYC 4002-2628-1, were obtained between November 2020 and November 2021. To determine the stellar atmospheric parameters, a spectral image was taken with the 2.16 m telescope…

We present the results from multi-wavelength observations of a transient discovered during the follow-up of S191213g, a gravitational wave (GW) event reported by the LIGO-Virgo Collaboration as a possible binary neutron star merger in a low…

We have identified a quadruple system with two close eclipsing binaries in TESS data. The object is unresolved in Gaia and appears as a single source at parallax 1.08~$\pm$0.01 mas. Both binaries have observable primary and secondary…

We present extensive radial-velocity observations of the intermediate polar DW Cnc during its 2018-2019 low state. We show that the 86 min signal, associated with the orbital period is strong in our radial velocity analysis, power spectrum…

We present broadband (gamma-ray, X-ray, near-infrared, optical, and radio) observations of the gamma-ray burst (GRB) 090709A and its afterglow in an effort to ascertain the origin of this high-energy transient. Previous analyses suggested…

V476 Cyg (Nova Cyg 1920) is a bright, fast nova reaching a photographic magnitude of 2.0. Using the Zwicky Transient Facility (ZTF) public database, I found that this nova is currently a dwarf nova with a cycle length of ~24 d. Compared to…

We present spectroscopy and orbital periods Porb of four relatively little-studied cataclysmic variable stars. The stars and their periods are: AF Cam, Porb = 0.324(1) d (the daily cycle count is slightly ambiguous); V2069 Cyg (= RX…

Building on previous work, a new search of the SuperWASP archive was carried out to identify eclipsing binary systems near the short-period limit. 143 candidate objects were detected with orbital periods between 16000 and 20000 s, of which…

The examination of two 2010 Chandra ACIS exposures of the Circinus galaxy resulted in the discovery of two pulsators: CXO J141430.1-651621 and CXOU J141332.9-651756. We also detected 26-ks pulsations in CG X-1, consistently with previous…

Gaia astrometry of nearby stars is precise enough to detect the tiny displacements induced by substellar companions, but radial velocity data are needed for definitive confirmation. Here we present radial velocity follow-up observations of…