Related papers: Protostellar accretion and the cosmological lithiu…
Understanding how dust evolves in protoplanetary disks is crucial to constraining the initial conditions of planet formation. The apparent "mass budget problem", which stems from the comparison of the observed disk masses to the ones…
Thirty years after the first observation of the 7Li isotope in the atmosphere of metal-poor halo stars, the puzzle about its origin persists. Do current observations still support the existence of a "plateau": a single value of lithium…
The process of mass accretion onto Young Stellar Objects (YSOs) plays a fundamental role in determining the final stellar mass and setting the initial conditions for planet formation. Despite its critical role, our understanding of…
The formation of a star is a dynamic process fed by the gravitational collapse of a molecular cloud core. Theoretical models and observations suggest that the majority of this infalling material settles into a protoplanetary disk before…
Recent theoretical work has shown that the pre-main-sequence (PMS) evolution of stars is much more complex than previously envisioned. Instead of the traditional steady, one-dimensional solution, accretion may be episodic and not…
The problem of the late accretion phase of the evolution of an axisymmetric, isothermal magnetic disk surrounding a forming star has been formulated in a companion paper. The "central sink approximation" is used to circumvent the problem of…
We present self-consistent calculations coupling numerical hydrodynamics simulations of collapsing pre-stellar cores and stellar evolution models of accreting objects. We analyse the main impact of consistent accretion history on the…
The dependence of lithium abundance on modified gravity in low-mass stellar objects is demonstrated. This may introduce an additional uncertainty to age determination techniques of young stars and globular clusters if they rely on the light…
We investigated the possibility of producing helium enhanced stars in globular clusters by accreting polluted matter during the pre-main sequence phase. We followed the evolution of two different classes of pre-main sequence accreting…
The existence of one percent of lithium-rich giant stars among normal, lithium-poor giant stars continues to be poorly explained. By merging two catalogues, one containing 10,535 lithium-rich giant stars with lithium abundances ranging from…
Aims. This study aims to determine the level and constancy of the Spite plateau as definitively as possible from homogeneous high-quality VLT-UVES spectra of 19 of the most metal-poor dwarf stars known. Methods. Our high-resolution (R ~…
Some recent observations of the abundances of s-process, r-process, and alpha elements in metal-poor stars have led to a new scenario for their formation. According to this scenario, these stars were born in a globular cluster and accreted…
Lithium has confused scientists for decades at almost each scale of the universe. Lithium-rich giants are peculiar stars with lithium abundances over model prediction. A large fraction of lithium-rich low-mass evolved stars are…
The success of primordial nucleosynthesis as a cornerstone of the hot Big Bang model has been limited by the long-standing lithium problem. Recent work presented a self-consistent perturbative analysis of the effects of variations in…
In the primordial Big Bang nucleosynthesis (BBN), only the lightest nuclides (D, $^3$He, $^4$He, and $^7$Li) were synthesized in appreciable quantities, and these relics provide us a unique window on the early universe. Currently, BBN…
The discovery of lithium-rich giants contradicts expectations from canonical stellar evolution. Here we report on the serendipitous discovery of 20 Li-rich giants observed during the Gaia-ESO Survey, which includes the first nine Li-rich…
The formation of massive stars is currently an unsolved problems in astrophysics. Understanding the formation of massive stars is essential because they dominate the luminous, kinematic, and chemical output of stars. Furthermore, their…
The protostellar luminosity function (PLF) is the present-day luminosity function of the protostars in a region of star formation. It is determined using the protostellar mass function (PMF) in combination with a stellar evolutionary model…
Lithium is predicted, and observed, to be depleted in contracting, low-mass pre main sequence (PMS) stars. Yet these stars reach the zero age main sequence (ZAMS) with a spread in lithium abundance at a given effective temperature that is…
Observational constraints on the primordial lithium abundance are important for the evaluation of the baryonic density of the universe. Its precise determination however suffers from uncertainties due to the possible depletion of this…