相关论文: Giant branch systems: surveys and populations

Exoplanets have been detected around stars at various stages of their lives, ranging from young stars emerging from formation, to latter stages of evolution, including white dwarfs and neutron stars. Post main sequence stellar evolution can…

Many planets are observed in stellar binary systems, and their frequency may be comparable to that of planetary systems around single stars. Binary stellar evolution in such systems influences the dynamical evolution of the resident…

Infrared studies have revealed debris likely related to planet formation in orbit around ~30% of youthful, intermediate mass, main sequence stars. We present evidence, based on atmospheric pollution by various elements heavier than helium,…

Most stars, perhaps even all stars, form in crowded stellar environments. Such star forming regions typically dissolve within ten million years, while others remain bound as stellar groupings for hundreds of millions to billions of years,…

Based on the large number of elliptical planetary nebulae I argue that about 55 per cent of all progenitors of planetary nebulae have planets around them. The planets spin up the stars when the later evolve along the red giant branch or…

Asteroid material is detected in white dwarfs (WDs) as atmospheric pollution by metals, in the form of gas/dust discs, or in photometric transits. Within the current paradigm, minor bodies need to be scattered, most likely by planets, into…

Circumstellar disks of planetary debris are now known or suspected to closely orbit hundreds of white dwarf stars. To date, both data and theory support disks that are entirely contained within the preceding giant stellar radii, and hence…

The vast majority of stars that populate the Universe will end their evolution as white-dwarf stars. Applications of white dwarfs include cosmochronology, evolution of planetary systems, and also as laboratories to study non-standard…

Massive stars play a major role in the evolution of their host galaxies, and serve as important probes of the distant Universe. It has been established that the majority of massive stars reside in close binaries and will interact with their…

Evolved stars dominate galactic spectra, enrich the galactic medium, expand to change their planetary systems, eject winds of a complex nature, produce spectacular nebulae and illuminate them, and transfer material between binary…

Understanding the formation, evolution, and chemical diversity of exoplanets are now central areas of astrophysics research. White dwarfs provide a uniquely sensitive laboratory for studying the end stages of planetary-system evolution and…

White dwarf stars are the most common endpoint of stellar evolution. Therefore, these old, numerous and compact objects provide valuable information on the late stages of stellar evolution, the physics of dense plasma and the structure and…

Giant planets dominate the mass of many planetary systems, including the Solar System, and represent the best-characterized class of extrasolar planets. Understanding the formation of giant planets bridges the high mass end of the planet…

The Gaia spacecraft presents an unprecedented opportunity to reveal the population of long period (a>1\,au) exoplanets orbiting stars across the H-R diagram, including white dwarfs. White dwarf planetary systems have played an important…

Direct imaging searches have begun to detect planetary and brown dwarf companions and to place constraints on the presence of giant planets at large separations from their host star. This work helps to motivate such planet searches by…

A survey of currently known planet-hosting stars indicates that approximately 25% of extrasolar planetary systems are within dual-star environments. Several of these systems contain stellar companions on moderately close orbits, implying…

Stars and planets are the fundamental objects of the Universe. Their formation processes, though related, may differ in important ways. Stars almost certainly form from gravitational collapse and probably have formed this way since the…

Studies of the resolved stellar populations in nearby systems are crucial to understand galaxy evolution. Here, we summarize how the interpretation of the colour-magnitude diagrams of field stars in late-type dwarfs inside and outside the…

Stars and planets form, live, and evolve in unison. Throughout the life of a star, dusty circumstellar discs and stellar outflows influence the further evolution of both the star(s) and their orbiting planet(s). Planet-forming discs, winds…

Internal dynamical evolution can drive stellar systems into states of high central density. For many star clusters and galactic nuclei, the time scale on which this occurs is significantly less than the age of the universe. As a result,…