相关论文: The origin of sdB stars (II)

Subdwarf B (sdB) stars (and related sdO/sdOB stars) are believed to be helium core-burning objects with very thin hydrogen-rich envelopes. In recent years it has become increasingly clear from observational surveys that a large fraction of…

Long-orbital-period subdwarf B (sdB) stars with main-sequence companions are believed to be the product of stable Roche Lobe overflow (RLOF), a scenario challenged by recent observations. Here we represent the results of a systematic study…

Binary population synthesis predicts the existence of subdwarf B stars (sdBs) with neutron star (NS) or black hole (BH) companions. We systematically investigate the formation of sdB+NS binaries from binary evolution and aim to obtain some…

Mounting evidence from subdwarf B (sdB) stars in the galactic field and their recently discovered counterparts in old open clusters indicates that at least two thirds of local disk sdB stars are binaries. Our recent radial velocity survey…

Models of binary star interactions have been successful in explaining the origin of field hot subdwarf (sdB) stars in short period systems, but longer-period systems that formed via Roche-lobe overflow (RLOF) mass transfer from the present…

Context: Subdwarf B stars (sdBs) play a crucial role in stellar evolution, asteroseismology, and far-UV radiation of early-type galaxies, and have been intensively studied with observation and theory. It has theoretically been predicted…

We present the results of a 3.5 year long campaign to measure orbital periods of subdwarf B (sdB) star binaries. We directly compare our observed orbital period distribution with that predicted by using binary population synthesis. Up to…

Binaries that contain a hot subdwarf (sdB) star and a main sequence companion may have interacted in the past. This binary population has historically helped determine our understanding of binary stellar evolution. We have computed a grid…

Wide binaries with hot subdwarf-B (sdB) primaries and main sequence companions are thought to form only through stable Roche lobe overflow (RLOF) of the sdB progenitor near the tip of the red giant branch (RGB). We present the orbital…

Hot subdwarf-B (sdB) stars in long-period binaries are found to be on eccentric orbits, even though current binary-evolution theory predicts these objects to be circularised before the onset of Roche-lobe overflow (RLOF). To increase our…

We considered the formation of detached white dwarf main-sequence star (WDMS) binaries through seven evolutionary channels subdivided according to the evolutionary process that gives rise to the formation of the white dwarf or its…

Hot subdwarf B stars (sdBs) are helium-burning stars with thin hydrogen-rich envelopes. Their most widely accepted formation channels involve binary evolution and progenitors near the tip of the red giant branch, thus studying these objects…

Hot subdwarf (sdB) stars in binary systems with main-sequence (MS) companions provide valuable insights into mass transfer and envelope ejection processes in binary evolution. Their mass ratios, orbital periods, and stellar properties…

The origin of hot subdwarf B stars (sdBs) is still unclear. About half of the known sdBs are in close binary systems for which common envelope ejection is the most likely formation channel. Little is known about this dynamic phase of binary…

The hot subdwarf O/B stars (sdO/Bs) are known as extreme horizontal branch stars, which is of great importance in stellar evolution theory. The sdO/Bs are generally thought to have a helium-burning core and a thin hydrogen envelope $(M_{\rm…

We propose a formation channel for the previously unexplained helium-rich subdwarf O (He-rich sdO) stars in which post-subdwarf B (sdB) stars (i.e. hybrid COHe white dwarfs) reignite helium burning in a shell after gaining matter from their…

We quantify an evolutionary channel for single sdB stars based on mergers of binaries containing a red giant star and a lower mass main sequence or brown dwarf companion in our Galaxy. Population synthesis calculations that follow mergers…

Subdwarf B (sdB) stars are thought to be core helium burning stars with low mass hydrogen envelopes. In recent years it has become clear that many sdB stars lose their hydrogen through interaction with a binary companion and continue to…

The origin of subdwarf B (sdB) stars is not fully understood yet since it requires high mass loss at the red giant stage. SdBs in close binary systems are formed via common envelope ejection, but the origin of apparently single sdB stars…

Most subdwarf B (sdB) + Helium white dwarf (He WD) binaries are believed to be formed from a particular channel. In this channel, the He WDs are produced first from red giants (RGs) with degenerate cores via stable mass transfer and sdB…