相关论文: Thermohaline mixing in low-mass giants

Helium burning is one of the most fundamental steps of stellar nucleosynthesis, as it describes the formation of life-determining element of carbon, while it plays a key role in the evolution of Red Giant, accreting White Dwarfs and Neutron…

At very low metallicity, the effects of differential rotation have a more important impact on the evolution of stars than at high metallicity. Rotational mixing leads to the production of great quantities of helium and of primary $^{14}$N…

Close tidal interactions of stars with a central massive black hole (MBH) or with other stars in the high density cusp around it can affect a significant fraction of the stellar population within the MBH radius of influence. We consider…

The evolution of helium stars with initial masses in the range 1.6 to 120 Msun is studied, including the effects of mass loss by winds. These stars are assumed to form in binary systems when their expanding hydrogenic envelopes are promptly…

GW190521 challenges our understanding of the late-stage evolution of massive stars and the effects of the pair-instability in particular. We discuss the possibility that stars at low or zero metallicity could retain most of their hydrogen…

We studied the effects of surface composition and thermohaline mixing caused by secular instability on the accreting components for low--mass binaries and applied the results on a short-orbital-period BS F190 in the old cluster M67. The…

If dark matter is made up of Weakly Interacting Massive Particles, the annihilation of these particles in halos results in energy being released, some of which is absorbed by gas, causing partial ionization and heating. Dark matter…

Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in Red Giant stars due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning…

(abbreviated) The evolution of intermediate mass stars at very low metallicity during their final thermal pulse asymptotic giant branch phase is studied in detail. As representative examples models with initial masses of 4Msun and 5Msun…

Rotational mixing is a very important but uncertain process in the evolution of massive stars. We propose to use close binaries to test its efficiency. Based on rotating single stellar models we predict nitrogen surface enhancements for…

We present extensive sets of stellar models for 0.8-9.0Msun in mass and -5 <= [Fe/H] <= -2 and Z = 0 in metallicity. The present work focuses on the evolutionary characteristics of hydrogen mixing into the He-flash convective zones during…

Mergers between helium white dwarfs and main-sequence stars are likely common, producing red giant-like remnants making up roughly a few percent of all low-mass ($\lesssim2M_\odot$) red giants. Through detailed modeling, we show that these…

The observations of carbon isotopic ratios in evolved stars suggest that non standard mixing is acting in low mass stars as they are ascending the red giant branch. We propose a simple consistent mechanism, based on the most recent…

The observed cosmic abundances of light elements are most consistent with each other, and with the predictions of big bang nucleosynthesis,if, contrary to the usual assumption, galactic chemical evolution reduces $(D+\ ^3He)/H$ with time.…

We study the evolution of gas in HII regions around the first stars after the death of the exciting stars. If the first star in a small halo dies without supernova (SN), subsequent star formation is possible in the same halo. We thus…

Stellar mergers are one important path to highly magnetised stars. Mergers of two low-mass white dwarfs may create up to every third hot subdwarf star. The merging process is usually assumed to dramatically amplify magnetic fields. However,…

Observations of stellar CNO isotope ratios indicate the presence of additional mixing processes on the red giant branch. An estimate of the resulting stellar He-3 depletion is made, as a function of stellar mass and metallicity. Based on…

It is predicted that orbital decay by gravitational-wave radiation and tidal interaction will cause some close-binary stars to merge within a Hubble time. The merger of a helium-core white dwarf with a main-sequence star can produce a red…

We study the statistics and cosmic evolution of massive black hole seeds formed during major mergers of gas-rich late-type galaxies. Generalizing the results of the hydro-simulations from Mayer et al. 2010, we envision a scenario in which a…

We recall the current status of the long-standing 3He problem, and its possible connection with chemical anomalies on the red giant branch. In this context, we collect in the literature all the available observations of the carbon isotopic…