Context. Grids of stellar models, computed with the same physical ingredients, allow one to study impact a given physics on broad range initial conditions and they are key ingredient for modeling evolution galaxies. Aims. We present here grid single star models masses between 0.8 120 M ⊙ , without rotation mass fraction heavy element Z = 0.006, representative Large Magellanic Cloud (LMC). Methods. used GENeva Evolution Code. The was until end central carbon-burning phase, early asymptotic...

Context. The first stars might have been fast rotators. This would important consequences for their radiative, mechanical, and chemical feedback. Aims. We discuss the impact of initial rotation on evolution massive Population III models nitrogen oxygen stellar yields. Methods. explore with masses in range 9 M ⊙ ≤ ini 120 , starting an zero-age main sequence equal to 70% critical one. Results. find that physics considered here, our rapidly rotating do not follow a homogeneous evolution. They...

The chemical enrichment of the early Universe is a crucial element in formation and evolution galaxies, Population III (Pop III) stars must play vital role this process. In study, we examine metal from massive Universe’s embryonic galaxies. Using radiation hydrodynamic simulations stellar modelling, calculated expected yield these stars. Specifically, applied accretion rates previous radiation-hydrodynamic simulation to inform our executed with Geneva code, across 11 selected datasets, final...

Context. The physics of stellar rotation plays a crucial role in the evolution stars, their final fates, and for properties compact remnants. Aims. Diverse approaches have been adopted to incorporate effects models. This study seeks explore consequences that these various prescriptions essential outputs massive star Methods. We computed grid 15 60 M ⊙ models with Geneva Stellar Evolution Code accounted both hydrodynamical magnetic instabilities induced by rotation. Results. In models, choice...

We present an analysis of the chemical compositions in high-redshift galaxies, with a focus on nitrogen-enhanced galaxies GN-z11 and CEERS-1019. used stellar models massive stars initial masses ranging from 9 to 120 M ⊙ various metallicities deduce abundances ejecta for few light elements (H, He, C, N, O). Our study reveals insights into processes elemental synthesis early Universe. find that Population III stars, particularly at fast equatorial rotation sampled top-heavy mass function, as...

Context. The Sun is a privileged laboratory of stellar evolution, thanks to the quality and complementary nature available constraints. Using these observations, we are able draw detailed picture its internal structure dynamics which form basis successes solar modelling. Amongst such constraints, depletion lithium beryllium key tracers required efficiency extent macroscopic mixing just below convective envelope. Thanks revised determinations abundances, may use them in conjunction with other...

Primordial supernovae were the first, great nucleosynthetic engines in Universe, forging elements required for later formation of planets and life. Here we show that planetesimals, precursors terrestrial planets, formed around low-mass stars debris first cosmic explosions 200 Myr after Big Bang, before galaxies far earlier than previously thought. A dense core one these collapsed to a protoplanetary disk which several Earth masses planetesimals 0.46 - 1.66 AU from their parent 0.7...

The Sun is a privileged laboratory of stellar evolution, thanks to the quality and complementary nature available constraints. Using these observations, we are able draw detailed picture its internal structure dynamics, which forms basis successes solar modelling. Amongst such constraints on depletion lithium beryllium key tracers required efficiency extent macroscopic mixing just below convective envelope. Thanks revised determinations abundances, may use them in conjunction with other...

The advent of the James Webb Space Telescope has revealed a wealth new galaxies just few hundred Myr after Big Bang. Some these exhibit unusual elemental abundances that are difficult to explain with stellar populations today. While Wolf-Rayet stars in multiple-burst populations, very massive or rapidly-rotating primordial stars, general relativistic explosions metal-enriched supermassive precursors globular clusters can principle account for supersolar nitrogen oxygen ratios GN-z11 and...

Context. Grids of stellar evolution models with rotation using the Geneva code (G ENEC ) have been published for a wide range metallicities. Aims. We introduce last remaining grid G models, metallicity Z = 10 −5 . study impact this extremely metal-poor initial composition on various aspects evolution, and compare it to results from previous grids at other provide electronic tables that can be used interpolate between tracks population synthesis. Methods. Using same physics as in papers...

Efforts to understand the origin and growth of massive black holes observed in early Universe have spurred significant interest evolution fate rapidly accreting primordial (metal-free) stars. Here, we investigate such Population III (PopIII) stars under variable accretion rates, focusing on thermal response stellar structure, impact luminosity wave encountered pre-main sequence (pre-MS) phase, influence their subsequent evolution. We employ Geneva code simulate ten models with varying...

Context. The first stars formed over five orders of magnitude in mass by accretion primordial dark matter halos. Aims. We study the evolution massive, very massive and supermassive (Pop III) nine rate. Methods. use stellar code GENEC to evolve accreting Pop III from 10 −6 –10 3 M ⊙ yr −1 how these rates determine final masses. are evolved until either end central Si burning or they encounter general relativistic instability (GRI). also examine metallicity affects star at one Results. At...

Accreting supermassive stars of ≳10 5 M ⊙ will eventually collapse directly to a black hole via the general-relativistic (GR) instability. Such direct collapses are thought be possible formation channel for holes at z > 6. In this work, we investigate final mass accreting Population III with constant accretion rates between 0.01 and 1000 yr −1 . We determined by solving differential equation GR linear adiabatic radial pulsations. find that models ≳0.05 experience instability masses...

The $^{26}$Al short-lived radioactive nuclide is the source of observed galactic diffuse $\gamma$-ray emission at 1.8 MeV. While different sources have been explored, such as AGB stars, massive stars winds, and supernovae, contribution very has never studied. We study stellar wind i.e with initial masses between 150 300 M$_\odot$, to enrichment in interstellar medium. discuss production by studying rotating non-rotating models M$_\odot$ for metallicities Z=0.006, 0.014, 0.020. confront this...

ABSTRACT Betelgeuse is a well-known bright red supergiant that shows semiregular variations with four approximate periods of 2200, 420, 230, and 185 d. While the longest period was customarily regarded as long secondary unknown origin, we identify ∼2200-d radial fundamental mode, three shorter first, second, third overtones. From linear non-adiabatic pulsation analysis including pulsation/convection coupling, have found these modes are all excited in envelope model late stage core carbon...

We present evolutionary models of massive, accreting population III stars with constant and variable accretion rates until the end silicon burning, final masses ~ 1000–3000 M ⊙ . In all our models, after core-hydrogen-burning phase, star expands towards red side Hertzsprung-Russell diagram is where it spends rest its evolution. During core helium exhibit an outer convective envelope as well many large intermediate zones. These zones allow for strong internal mixing to occur which enriches...

The chemical enrichment of the early Universe is a crucial element in formation and evolution galaxies, Population III (PopIII) stars must play vital role this process. In study, we examine metal from massive Universe's embryonic galaxies. Using radiation hydrodynamic simulations stellar modelling, calculated expected yield these stars. Specifically, applied accretion rates previous radiation-hydrodynamic simulation to inform our executed with Geneva code, across 11 selected datasets, final...

Accreting supermassive stars of $\gtrsim 10^{5}\,M_\odot$ will eventually collapse directly to a black hole via the general relativistic (GR) instability. Such direct collapses are thought be possible formation channel for holes at $z > 6$. In this work, we investigate final mass accreting Population III with constant accretion rates between $0.01$ and $1000\,M_\odot$yr$^{-1}$. We determine by solving differential equation linear adiabatic radial pulsations. find that models...

Betelgeuse is a well known bright red supergiant that shows semi-regular variations with four approximate periods of 2200, 420, 230, and 185 days. While the longest period was customarily regarded as LSP (long secondary period) unknown origin, we identify ~2200-d radial fundamental mode, three shorter first, second, third overtones. From linear nonadiabatic pulsation analysis including pulsation/convection coupling, have found these modes are all excited in envelope model late stage...

The first stars might have been fast rotators. This would important consequences for their radiative, mechanical and chemical feedback. We discuss the impact of initial rotation on evolution massive Population III models nitrogen oxygen stellar yields. explore with masses in range 9Msol < Mini 120Msol starting an Zero Age Main Sequence equal to 70% critical one. find that physics considered here, our rapidly-rotating do not follow a homogeneous evolution. They lose very little mass case...

We present an analysis of the chemical compositions in high-redshift galaxies, with a focus on nitrogen-enhanced galaxies GN-z11 and CEERS-1019. use stellar models massive stars initial masses ranging from 9 to 120 Msol across various metallicities deduce abundances ejecta for few light elements (H, He, C, N, O). Our study reveals insights into processes elemental synthesis early universe. find that Population III stars, particularly at fast equatorial rotation sampled top-heavy mass...

Grids of stellar evolution models with rotation using the Geneva code (Genec) have been published for a wide range metallicities. We introduce last remaining grid Genec models, metallicity $Z=10^{-5}$. study impact this extremely metal-poor initial composition on various aspects evolution, and compare it to results from previous grids at other provide electronic tables that can be used interpolate between tracks population synthesis. Using same physics as in papers series, we computed...

The first stars formed over five orders of magnitude in mass by accretion primordial dark matter halos. We study the evolution massive, very massive and supermassive (Pop III) nine rate. use stellar code GENEC to evolve accreting Pop III from 10$^{-6}$ - 10$^3$ M$_\odot$/yr how these rates determine final masses. are evolved until either end central Si burning or they encounter general relativistic instability (GRI). also examine metallicity affects stars. At below $2.5 x 10^{-5}$ star falls...

The origin of supermassive black holes (SMBHs) is a key open question for contemporary astrophysics and cosmology. Here we review the features cosmological model SMBH formation from Pop III.1 seeds, i.e., remnants metal-free stars forming in locally-isolated minihalos, where energy injection dark matter particle annihilation alters structure protostar allowing growth to scales (Banik et al. 2019; Singh 2023; Cammelli 2024). explains paucity intermediate-mass (IMBHs) via characteristic seed...

Efforts to understand the origin and growth of massive black holes observed in early Universe have spurred a strong interest evolution fate rapidly-accreting primordial (metal-free) stars. Here, we investigate such Population III stars under variable accretion rates, focusing on thermal response stellar structure, impact luminosity wave encountered pre-main sequence phase, influence their subsequent evolution. We employ Geneva code simulate ten models with varying histories, covering final...