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Related papers: R-Process in Collapsing O/Ne/Mg Cores

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We study turbulent gas diffusion affects on $r$-process abundances in Milky Way stars, by a combination of an analytical approach and a Monte Carlo simulation. Higher $r$-process event rates and faster diffusion, lead to more efficient…

High Energy Astrophysical Phenomena · Physics 2020-06-24 Paz Beniamini , Kenta Hotokezaka

It has been recently proposed that the shocked surface layers of exploding O-Ne-Mg cores provide the conditions for r-process nucleosynthesis, because their rapid expansion and high entropies enable heavy r-process isotopes to form even in…

Astrophysics · Physics 2009-11-13 H. -Th. Janka , B. Mueller , F. S. Kitaura , R. Buras

Extensive progress has been recently made into our understanding of heavy element production via the $r$-process in the Universe, specifically with the first observed neutron star binary merger (NSBM) event associated with the gravitational…

The r-process involves neutron-rich nuclei far off stability for which no experimental cross sections are known. Therefore, one has to rely on theory. The difficulties in the predictions are briefly addressed. To investigate the impact of…

Astrophysics · Physics 2015-06-24 T. Rauscher

The third r-process peak (Os, Ir, Pt) is poorly understood due to observational challenges, with spectral lines located in the blue or near-ultraviolet region of stellar spectra. These challenges need to be overcome for a better…

We investigate r-process nucleosynthesis in three-dimensional (3D) general-relativistic magnetohydrodynamic simulations of rapidly rotating strongly magnetized core collapse. The simulations include a microphysical finite-temperature…

High Energy Astrophysical Phenomena · Physics 2018-09-19 Philipp Mösta , Luke F. Roberts , Goni Halevi , Christian D. Ott , Jonas Lippuner , Roland Haas , Erik Schnetter

We suggest that if the astrophysical site for r-process nucleosynthesis in the early Galaxy is confined to a narrow mass range of Type II supernova (SN II) progenitors, with a lower mass limit of Mms = 20 Msun, a unique feature in the…

Astrophysics · Physics 2009-10-31 Takuji Tsujimoto , Toshikazu Shigeyama , Yuzuru Yoshii

Despite recent progress, the astrophysical channels responsible for rapid neutron capture (r-process) nucleosynthesis remain an unsettled question. Observations of kilonovae following gravitational wave-detected neutron star mergers…

High Energy Astrophysical Phenomena · Physics 2022-11-30 Jennifer Barnes , Brian D. Metzger

We have studied whether the rotation and magnetic fields in neutrino-driven winds can be key processes for the rapid-process (r-process) nucleosynthesis. We have examined the features of a steady and subsonic wind solutions which extend the…

Astrophysics · Physics 2015-06-24 S. Nagataki , K. Kohri

We use cosmological, magnetohydrodynamical simulations of Milky Way-mass galaxies from the Auriga project to study their enrichment with rapid neutron capture (r-process) elements. We implement a variety of enrichment models from both…

During the first 20 seconds of its life, the enormous neutrino luminosity of a neutron star drives appreciable mass loss from its surface. This neutrino-driven wind has been previously identified as a likely site for the r-process. Qian &…

Astrophysics · Physics 2011-05-05 R. D. Hoffman , S. E. Woosley , Y. -Z. Qian

The mechanism responsible for the natal kicks of neutron stars continues to be a challenging problem. Indeed, many mechanisms have been suggested, and one hydrodynamic mechanism may require large initial asymmetries in the cores of…

Astrophysics · Physics 2009-11-10 Jeremiah Murphy , Adam Burrows , Alexander Heger

The existence of various anomalous stars, such as the first stars in the universe or stars produced by stellar mergers, has been recently proposed. Some of these stars will result in black hole formation. In this study, we investigate iron…

Astrophysics · Physics 2010-05-12 Ken'ichiro Nakazato , Kohsuke Sumiyoshi , Shoichi Yamada

We solve the general-relativistic steady-state eigenvalue problem of neutrino-driven protoneutron star winds, which immediately follow core-collapse supernova explosions. We provide velocity, density, temperature, and composition profiles…

Astrophysics · Physics 2011-05-05 Todd A. Thompson , Adam Burrows , Bradley S. Meyer

An update on astrophysical models for nucleosynthesis via rapid neutron capture, the r process, is given. A neutrino-induced r process in supernova helium shells may have operated up to metallicities of ~10^-3 times the solar value. Another…

Solar and Stellar Astrophysics · Physics 2015-06-03 Yong-Zhong Qian

The neutrino-driven wind from proto-neutron stars is a proposed site for r-process nucleosynthesis, although most previous work has found that a wind heated only by neutrinos cannot produce the third r-process peak. However, several groups…

High Energy Astrophysical Phenomena · Physics 2023-02-06 Brian Nevins , Luke F. Roberts

Results from observations report a growing number of metal-poor stars showing an abundance pattern midway between the s- and r-processes. These so-called r/s-stars raise the need for an intermediate neutron capture process (i-process),…

Solar and Stellar Astrophysics · Physics 2022-06-29 A. Choplin , L. Siess , S. Goriely

A promising astrophysical site to produce the lighter heavy elements of the first $r$-process peak ($Z = 38-47$) is the moderately neutron rich ($0.4 < Y_e < 0.5$) neutrino-driven ejecta of explosive environments, such as core-collapse…

High Energy Astrophysical Phenomena · Physics 2022-08-17 A. Psaltis , A. Arcones , F. Montes , P. Mohr , C. J. Hansen , M. Jacobi , H. Schatz

We present detailed chemical abundances of three new bright (V ~ 11), extremely metal-poor ([Fe/H] ~ -3.0), r-process-enhanced halo red giants based on high-resolution, high-S/N Magellan/MIKE spectra. We measured abundances for 20-25…

This manuscript reviews recent progress in our understanding of the nucleosynthesis of medium and heavy elements in supernovae. Recent hydrodynamical models of core-collapse supernovae show that a large amount of proton rich matter is…

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