Related papers: Evolutionary and structural properties of mirror s…
We study the effects of WIMP dark matter (DM) on the collapse and evolution of the first stars in the Universe. Using a stellar evolution code, we follow the pre-Main Sequence (MS) phase of a grid of metal-free stars with masses in the…
One of the deepest unsolved puzzles of subatomic physics is why Nature prefers the left particles to the right ones. Mirror matter is an attempt to understand this mystery by assuming the existence of a "parallel''world where this…
A mechanism is identified whereby dark matter (DM) in protostellar halos dramatically alters the current theoretical framework for the formation of the first stars. Heat from neutralino DM annihilation is shown to overwhelm any cooling…
Recent models of rotating massive stars including magnetic fields prove it difficult for the cores of single stars to retain enough angular momentum to produce a collapsar and gamma-ray burst. At low metallicity, even very massive stars may…
We present results of cosmological N-body hydrodynamic chemistry simulations of primordial structure growth and evolution in a scenario with warm dark matter (WDM) having a mass of 3 keV (thermal relic) and compare with a model consisting…
Hot subdwarf stars with masses above $0.8 M_\odot$ ascend the helium giant branch after the end of core helium burning, before entering the white dwarf cooling track or exploding as type Ib/c supernovae. Such massive helium stars are…
We present an analysis of the formation and chemical evolution of stellar haloes around (a) Milky Way Analogue (MWA) galaxies and (b) galaxy clusters in the L-Galaxies 2020 semi-analytic model of galaxy evolution. Observed stellar halo…
Mirror matter is an entirely new form of matter predicted to exist if mirror symmetry is a fundamental symmetry of nature. Mirror matter has the right broad properties to explain the inferred dark matter of the Universe and might also be…
We determine the average metallicities of the elements of cold halo substructure (ECHOS) that we previously identified in the inner halo of the Milky Way within 17.5 kpc of the Sun. As a population, we find that stars kinematically…
The evolution of helium stars with masses of 1.5 - 6.7 M_sun in binary systems with a 1.4 M_sun neutron-star companion is presented. Such systems are assumed to be the remnants of Be/X-ray binaries with B-star masses in the range of 8 - 20…
The existence of a shadow world (or mirror universe) with matter and forces identical to that of the visible world but interacting with the latter only via gravity can be motivated by superstring theories as well as by recent attempts to…
Mergers of compact binaries (of a neutron star and another neutron star or a black hole, NSMs) are suggested to be the promising astrophysical site of the r-process. While the average coalescence timescale of NSMs appears to be > 100 Myr,…
The Milky Way dark matter halo is formed from the accretion of smaller subhalos. These sub-units also harbor stars---typically old and metal-poor---that are deposited in the Galactic inner regions by disruption events. In this Letter, we…
After a brief review of our current understanding of Miras and their evolutionary status, three aspects of ``real-time'' evolution in these and related stars are examined: # Chemical changes (O-rich to C-rich) due to third dredge-up #…
Massive star formation exhibits an extremely rich chemistry. However, not much evolutionary details are known yet, especially at high spatial resolution. Therefore, we synthesize previously published Submillimeter Array…
In this review we outline the major points of ab-initio cosmological models focusing on some galaxy evolution unresolved problems. In particular our knowledge of the star formation rate which leads galaxy evolution, i.e. luminosity, colors…
Young stars on their way to the ZAMS evolve in significantly different ways depending on mass. While the theoretical and observational properties of low- and intermediate-mass stars are rather well understood and/or empirically tested, the…
We investigate the star formation and chemical evolution in the early universe by considering the merging history of the Galaxy in the {\Lambda}CDM scenario according to the extended Press-Schechter theory. We give some possible constraints…
We present the findings of a comprehensive and detailed analysis of merger tree data from ultra-high-resolution cosmological $N$-body simulations. The analysis, conducted with a particle mass resolution of $5 \times 10^3 h^{-1} M_{\odot}$…
If dark matter is made of mirror baryons, they are present in all gravitationally bound structures. Here we investigate some effects of mirror dark matter on neutron stars and discuss possible observational consequences. The…