A strong neutron burst in jet-like supernovae of spinstars

Abstract

Some metal-poor stars have abundance patterns which are midway between the slow (s) and rapid (r) neutron capture processes. We show that the helium shell of a fast rotating massive star experiencing a jet-like explosion undergoes two efficient neutron capture processes: one during stellar evolution and one during the explosion. It eventually provides a material whose chemical composition is midway between the s- and r-process. A low metallicity 40~$M_{\odot }$ model with an initial rotational velocity of $\sim 700$~km~s${}^{-1}$ was computed from birth to pre-supernova with a nuclear network following the slow neutron capture process. A 2D hydrodynamic relativistic code was used to model a $E=10^{52}$~erg relativistic jet-like explosion hitting the stellar mantle. The jet-induced nucleosynthesis was calculated in post-processing with a network of 1812 nuclei. During the star's life, heavy elements from $30\lesssim Z\lesssim 82$ are produced thanks to an efficient s-process, which is boosted by rotation. At the end of evolution, the helium shell is largely enriched in trans-iron elements and in (unburnt) ${}^{22}$Ne, whose abundance is $\sim 20$ times higher than in a non-rotating model. During the explosion, the jet heats the helium shell up to $\sim 1.5$ GK. It efficiently activates ($\alpha ,n$) reactions, such as ${}^{22}$Ne($\alpha ,n$), and leads to a strong n-process with neutron densities of $\sim 10^{19}-10^{20}$~cm${}^{-3}$ during $0.1$~second. This has the effect of shifting the s-process pattern towards heavier elements (e.g. Eu). The resulting chemical pattern is consistent with the abundances of the carbon-enhanced metal-poor r/s star CS29528-028, provided the ejecta of the jet model is not homogeneously mixed. This is a new astrophysical site which can explain at least some of the metal-poor stars showing abundance patterns midway between the s- and r-process.

arXiv comment9 pages, 12 figures, accepted in A&A

References in corpus (80)

• Collapsars - Gamma-Ray Bursts and Explosions in "Failed Supernovae"
• Presupernova Evolution of Rotating Massive Stars I: Numerical Method and Evolution of the Internal Stellar Structure
• The Progenitor Stars of Gamma-Ray Bursts
• Nucleosynthesis in Massive Stars With Improved Nuclear and Stellar Physics
• The r-process of stellar nucleosynthesis: Astrophysics and nuclear physics achievements and mysteries
• Rotating Massive Main-Sequence Stars I: Grids of Evolutionary Models and Isochrones
• The s Process: Nuclear Physics, Stellar Models, Observations
• Nucleosynthesis Yields of Core-Collapse Supernovae and Hypernovae, and Galactic Chemical Evolution
• Nucleosynthesis and Evolution of Massive Metal-Free Stars
• The Dawes Review 2: Nucleosynthesis and stellar yields of low and intermediate-mass single stars
• Production of all the r-process nuclides in the dynamical ejecta of neutron star mergers
• Presupernova evolution and explosive nucleosynthesis of rotating massive stars in the metallicity range -3 <=[Fe/H]<= 0
• Neutron-Capture Elements in the Early Galaxy: Insights from a Large Sample of Metal-Poor Giants
• Magnetorotationally driven Supernovae as the origin of early galaxy $r$-process elements?
• The Extremely Metal-Poor, Neutron-Capture-Rich Star CS 22892-052: A Comprehensive Abundance Analysis
• Near-Field Cosmology with Metal-Poor Stars
• Carbon Enhanced Metal-Poor Stars. I. Chemical Compositions of 26 Stars
• First-generation black-hole-forming supernovae and the metal abundance pattern of a very iron-poor star
• R-process enrichment from a single event in an ancient dwarf galaxy
• The early star generations: the dominant effect of rotation on the CNO yields
• Collapsars as a major source of r-process elements
• The Rise of the s-Process in the Galaxy
• Neutron Star Mergers and Nucleosynthesis of Heavy Elements
• The Most Metal-Poor Stars. II. Chemical Abundances of 190 Metal-Poor Stars Including 10 New Stars With [Fe/H] < -3.5
• The r-process nucleosynthesis in the various jet-like explosions of magnetorotational core-collapse supernovae
• Supernova Nucleosynthesis in Population III 13 -- 50 $M_{\odot }$ Stars and Abundance Patterns of Extremely Metal-Poor Stars
• The first chemical enrichment in the universe and the formation of hyper metal-poor stars
• The s process in asymptotic giant branch stars of low metallicity and the composition of carbon-enhanced metal-poor stars
• Very low metallicity massive star models: Pre-SN evolution and primary nitrogen production
• $s$-process production in rotating massive stars at solar and low metallicities
• Convective-reactive proton-C12 combustion in Sakurai's object (V4334 Sagittarii) and implications for the evolution and yields from the first generations of stars
• A holistic approach to carbon-enhanced metal-poor stars
• The Most Metal-Poor Stars. IV. The Two Populations With [Fe/H] < -3.0
• Non-standard s process in low metallicity massive rotating stars
• The intermediate neutron-capture process and carbon-enhanced metal-poor stars
• The s process in massive stars at low metallicity. Effect of primary N14 from fast rotating stars
• Observational Constraints on First-Star Nucleosynthesis. I. Evidence for Multiple Progenitors of CEMP-no Stars
• TOPoS: II. On the bimodality of carbon abundance in CEMP stars. Implications on the early chemical evolution of galaxies
• The $R$-Process Alliance: First Release from the Southern Search for $r$-Process-Enhanced Stars in the Galactic Halo
• The role of binaries in the enrichment of the early Galactic halo. III. Carbon-enhanced metal-poor stars -- CEMP-s stars
• The Hamburg/ESO R-process Enhanced Star survey (HERES) III. HE 0338-3945 and the formation of the r+s stars
• Abundance Profiling of Extremely Metal-Poor Stars and Supernova Properties in the Early Universe
• The R-Process Alliance: First Release from the Northern Search for r-Process Enhanced Metal-Poor Stars in the Galactic Halo
• s-Process in Low Metallicity Stars. I. Theoretical Predictions
• Astronuclear Physics: a Tale of the Atomic Nuclei in the Skies
• The Initial mass function of the first stars inferred from extremely metal-poor stars
• Are C-rich ultra iron poor stars also He-rich?
• s-Process in Low Metallicity Stars. III. Individual analysis of CEMP-s and CEMP-s/r with AGB models
• The Connection between Gamma-Ray Bursts and Extremely Metal-Poor Stars: Black Hole-forming Supernovae with Relativistic Jets
• Aspherical Properties of Hydrodynamics and Nucleosynthesis in Jet-induced Supernovae
• The Nucleosynthetic Imprint of 15-40 Solar Mass Primordial Supernovae on Metal-Poor Stars
• First stars IV.CS 29497-030: Evidence for operation of the s-process at very low metallicity
• i-process nucleosynthesis and mass retention efficiency in He-shell flash evolution of rapidly accreting white dwarfs
• Thermohaline mixing and gravitational settling in carbon-enhanced metal-poor stars
• On the origin of HE0107-5240, the most iron deficient star presently known
• The Diverse Origins of Neutron-Capture Elements in the Metal-Poor Star HD 94028: Possible Detection of Products of i-process Nucleosynthesis
• Elemental abundances and classification of CEMP stars
• Idealised hydrodynamic simulations of turbulent oxygen-burning shell convection in 4π geometry
• Non standard s-process in massive rotating stars. Yields of $10-150$ $M_{\odot }$ models at $Z=10^{-3}$
• $r$-Process Nucleosynthesis from Three-dimensional Jet-driven Core-Collapse Supernovae with Magnetic Misalignments
• Pop III $\text{i}$-process Nucleosynthesis and the Elemental Abundances of SMSS J0313-6708 and the Most Iron-Poor Stars
• Barium Isotopic Composition of Mainstream Silicon Carbides from Murchison: Constraints for s-Process Nucleosynthesis in AGB Stars
• The i-process yields of rapidly-accreting white dwarfs from multicycle He-shell flash stellar evolution models with mixing parameterizations from 3D hydrodynamics simulations
• The first stars: CEMP--no stars and signatures of spinstars
• Carbon-rich presolar grains from massive stars. Subsolar 12C/13C and 14N/15N ratios and the mystery of 15N
• Metal-Poor Stars Observed with the Magellan Telescope I. Constraints on Progenitor Mass and Metallicity of AGB Stars Undergoing s-Process Nucleosynthesis
• Carbon-enhanced metal-poor stars: a window on AGB nucleosynthesis and binary evolution. II. Statistical analysis of a sample of 67 CEMP-$s$ stars
• New Neutron-Capture Site in Massive Pop III and Pop II Stars as a Source for Heavy Elements in the Early Galaxy
• Stellar Yields of Rotating First Stars. I. Yields of Weak Supernovae and Abundances of Carbon-enhanced Hyper Metal Poor Stars
• Learning about the intermediate neutron-capture process from lead abundances
• Hypernovae and Other Black-Hole-Forming Supernovae
• Are some CEMP-s stars the daughters of spinstars?
• How plausible are the proposed formation scenarios of CEMP-r/s stars?
• Relics of ancient post-AGB stars in a primitive meteorite
• The R-Process Alliance: Discovery of the first metal-poor star with a combined r- and s-process element signature
• Constraints on CEMP-no progenitors from nuclear astrophysics
• The Chemical Abundances of Stars in the Halo (CASH) Project. III. A New Classification Scheme for Carbon-Enhanced Metal-poor Stars with S-process Element Enhancement
• New \textsl{s}-process Mechanism in Rapidly-Rotating Massive Pop II Stars
• Pre-supernova mixing in CEMP-no source stars
• Inferring the velocity of early massive stars from the abundances of extremely metal-poor stars

Cited by in corpus (8)

• R-Process elements from magnetorotational hypernovae
• Heavy elements in barium stars
• The p-process in exploding rotating massive stars
• r-Process Radioisotopes from Near-Earth Supernovae and Kilonovae
• Mono-enriched stars and Galactic chemical evolution -- Possible biases in observations and theory
• Collective neutrino oscillations and heavy-element nucleosynthesis in supernovae: exploring potential effects of many-body neutrino correlations
• Origin of metals in old Milky Way halo stars based on GALAH and Gaia
• Merger Conditions of Population III Protostar Binaries