Related papers: Observational Constraints for Thermohaline Mixing
In spite of the efforts made in the latest years, still there is no comprehensive explanation for the chemical anomalies of globular cluster stars. Among these, the most striking is oxygen depletion, which reaches values down to [O/Fe]~-0.4…
We study the nucleosynthesis and the induced mixing during the merging of massive stars inside a common envelope. The systems of interest are close binaries, initially consisting of a massive red supergiant and a main-sequence companion of…
This paper presents a study of the specific merger rate as a function of group membership, local environment, and redshift in a very large, $500h^{-1} Mpc$, cosmological N-body simulation, the \textit{Millennium Simulation}. The goal is to…
For massive black hole binaries produced in galactic mergers, we examine the possibility of inspiral induced by interaction with field stars. We model the evolution of such binaries for a range of galaxy core and binary parameters, using…
The method developed by Raffelt (1990a,b,c) to estimate a possible increase in the standard values of the helium-core mass at the tip of the red giant branch, $\Mc$, from properties of the color-magnitude diagrams of Galactic globular…
An exciting recent finding regarding scaling relations among globular clusters is the so-called 'blue tilt': clusters of the blue sub-population follow a trend of redder colour with increasing luminosity. In this paper we evaluate to which…
In Martell & Grebel (2010) we reported the discovery in the Sloan Digital Sky Survey-II/SEGUE spectroscopic database of a small subset of halo red giants, 2.5%, with CN and CH band strengths indicative of globular-cluster-like carbon and…
Three-dimensional molecular dynamics simulations of dissipative particles (~ 10^6) are carried out for studying the clustering kinetics of granular media during cooling. The inter-connected high particle density regions are identified,…
We have calculated the evolution of low metallicity red giant stars under the assumption of deep mixing between the convective envelope and the hydrogen burning shell. We find that the extent of the observed abundance anomalies, and in…
Space missions like CoRoT, Kepler, and TESS have made asteroseismology a powerful probe of stellar interiors. Red giants are key targets thanks to their rich mixed-mode oscillation spectra, which reveal properties of both core and envelope.…
Equilibrium properties of hydrogen-helium mixtures under conditions similar to the interior of giant gas planets are studied by means of first principle density functional molecular dynamics simulations. We investigate the molecular and…
This paper shows that magnetic reconnection could be an important heating process in cosmic gases. In any volume where magnetized plasmas collide, the dissipation of magnetic energy via reconnection seems to be unavoidable. Since most…
We revisit the process of gravitational sedimentation of helium and heavy elements in the intra-cluster medium. We find that helium applies an inward drag force on heavy elements, boosting their sedimentation speed to nearly half its own.…
We examine whether nonthermal protons energized during a cluster merger are simultaneously responsible for the Coma cluster's diffuse radio flux (via secondary decay) and the departure of its intra-cluster medium (ICM) from a thermal…
We show that enhanced extra mixing in low-mass red giants can result in a fluorine abundance that is correlated with abundance variations of other elements participating in H burning, such as C, N, O and Na. This finding is used to explain…
The red-giant branch bump provides valuable information for the investigation of the internal structure of low-mass stars. Because current models are unable to accurately predict the occurrence and efficiency of mixing processes beyond…
In large scale structure formation, massive systems assemble through the hierarchical merging of less massive ones. Galaxy clusters, being the most massive and thus the most recent collapsed structures, still grow by accreting smaller…
Mergers between red galaxies are observed to be common in the nearby Universe, and are thought to be the dominant mechanism by which massive galaxies grow their mass at late times. These ``dry'' mergers can be readily identified in very…
Both absorption and emission line studies show that cold gas around galaxies is commonly outflowing at speeds of several hundred km$\,\textrm{s}^{-1}$. This observational fact poses a severe challenge to our theoretical models of galaxy…
Red Clump stars have been found to be enhanced in lithium relative to stars at the tip of the Red Giant Branch (TRGB), which is unexpected in current stellar models. At the TRGB, stars undergo the helium flash, during which helium burning…