相关论文: An evolutionary scenario for the U Scorpii
We have found a new evolutionary path to Type Ia supernovae (SNe Ia) which has been overlooked in previous work. In this scenario, a carbon-oxygen white dwarf (C+O WD) is originated, not from an asymptotic giant branch star with a C+O core,…
Type Ib/c supernovae (SNe Ib/c) mark the deaths of hydrogen-deficient massive stars. The evolutionary scenarios for SNe Ib/c progenitors involve many important physical processes including mass loss by winds and its metallicity dependence,…
Mass transfer from an evolved donor star to its binary companion is a standard feature of stellar evolution in binaries. In wide binaries, the companion star captures some of the mass ejected in a wind by the primary star. The captured…
Virtually all binaries consisting of a white dwarf with a non-degenerate companion can be classified as either close post-interaction systems (with orbital periods of a few days or less), or wide systems (with periods longer than decades),…
Improved observations of globular clusters are uncovering a large number of radio pulsars and of X-ray sources. The latter include binaries in which a neutron star or a white dwarf accretes matter from a companion, recycled pulsars, and…
We show that stable disk accretion should be very rare among low-mass X-ray binaries and cataclysmic variables whose evolution is driven by the nuclear expansion of the secondary star on the first giant branch. Stable accretion is confined…
We present optical and NIR spectroscopic observations of U Sco 2010 outburst. From the analysis of lines profiles we identify a broad and a narrow component and show that the latter originates from the reforming accretion disk. We show that…
We present a brief summary of the Single Degenerate Scenario for the progenitors of Type Ia Supernovae in which it is assumed that a low mass carbon-oxygen white dwarf is growing in mass as a result of accretion from a secondary star in a…
The spinning-up of the accreting component in the process of conservative mass exchange is considered in binary systems - progenitors of systems consisting of a main sequence Be-star and an O-subdwarf. During the mass exchange, the…
Dynamical interactions that take place between objects in dense stellar systems lead to frequent formation of exotic stellar objects, unusual binaries, and systems of higher multiplicity. They are most important for the formation of…
We present the results of a systematic exploration of an alternative evolutionary scenario to form double neutron-star binaries, first proposed by Brown (1995), which does not involve a neutron star passing through a common envelope. In…
Among the extrasolar planetary systems about 30 are located in a stellar binary orbiting one of the stars, preferably the more massive primary. The dynamical influence of the second companion alters firstly the orbital elements of the…
We present the results of a high-resolution imaging survey of 12 brown dwarfs and very low mass stars in the closest (~145 pc) young (~5 Myr) OB association, Upper Scorpius. We obtained images with the Advanced Camera for Surveys/High…
The chemical composition of stellar photospheres in mass-transferring binary systems is a precious diagnostic of the nucleosynthesis processes that occur deep within stars, and preserves information on the components history. The binary…
In the course of our search for double degenerate binaries as potential progenitors of type Ia supernovae with the UVES spectrograph at the ESO VLT (ESO SN Ia Progenitor surveY - SPY) we discovered that the sdB star HE 1047-0436 is radial…
Over the last decades, numerous wide (>1000 AU) binaries have been discovered in the Galactic field and halo. The origin of these wide binaries cannot be explained by star formation or by dynamical interactions in the Galactic field. We…
Ultra-stripped supernovae are different from other terminal explosions of massive stars, as they show little or no ejecta from the actual supernova event. They are thought to occur in massive binary systems after the exploding star has lost…
Recurrent nova U Scorpii (U Sco) is one of the prototypes for a Type Ia supernova progenitor. The logic is that the white dwarf is near the Chandrasekhar mass and gas is accumulating onto its surface at a near-maximal accretion rate, so it…
Beginning from massive binaries in the Galaxy we evolve black-hole, neutron-star binaries and binary neutron stars, such as the Hulse-Taylor system PSR 1913+16. The new point in our evolution is a quantitative calculation of the accretion…
In the single degenerate (SD) scenario for type Ia supernovae (SNe Ia), a mass-accreting white dwarf is expected to experience a supersoft X-ray source (SSS) phase. However, some recent observations showed that the expected number of the…