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Related papers: Effects of Pycnonuclear Reactions on White Dwarf S…

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Recent determinations of the total rate of the 12C+12C nuclear reaction show non-negligible differences with the reference reaction rate commonly used in previous stellar simulations. In addition, the current uncertainties in determining…

Thermonuclear supernovae result when interaction with a companion reignites nuclear fusion in a carbon-oxygen white dwarf, causing a thermonuclear runaway, a catastrophic gain in pressure, and the disintegration of the whole white dwarf. It…

High Energy Astrophysical Phenomena · Physics 2015-06-05 Marten H. van Kerkwijk

Nuclear reactions may affect gravitational-wave signals from neutron-star mergers, but the impact is uncertain. In order to quantify the effect, we compare two numerical simulations representing intuitive extremes. In one case reactions…

High Energy Astrophysical Phenomena · Physics 2022-05-24 Peter Hammond , Ian Hawke , Nils Andersson

We analyze thermonuclear and pycnonuclear fusion reactions in dense matter containing atomic nuclei of different types. We extend a phenomenological expression for the reaction rate, proposed recently by Gasques et al. (2005) for the…

Astrophysics · Physics 2009-11-11 D. G. Yakovlev , L. R. Gasques , M. Beard , M. Wiescher , A. V. Afanasjev

In this work, we study the effects of temperature on magnetic white dwarfs. We model their interior as a nuclei lattice surrounded by a relativistic free Fermi gas of electrons, accounting for effects from temperature, Landau levels and…

Solar and Stellar Astrophysics · Physics 2021-11-03 J. Peterson , V. Dexheimer , R. Negreiros , B. G. Castanheira

We consider the evolution of white dwarfs with compact object companions (specifically black holes with masses up to 10^6 solar masses, neutron stars, and other white dwarfs). We suppose that the orbits are initially quite elliptical and…

Astrophysics · Physics 2009-11-10 Yasser Rathore , Roger D. Blandford , Avery E. Broderick

We use the results of realistic N-body simulations to investigate the appearance of the white dwarf population in dense star clusters. We show that the presence of a substantial binary population in a star cluster, and the interaction of…

Astrophysics · Physics 2009-11-07 Jarrod R. Hurley , Michael M. Shara

The influence of the metallicity at the main sequence on the chemical structure of the exploding white dwarf, the nucleosynthesis during the explosion and the light curves of an individual Type Ia supernovae have been studied. Detailed…

Astrophysics · Physics 2009-10-31 P. Höflich , K. Nomoto , H. Umeda , J. C. Wheeler

We present detailed theoretical mass-radius relations for massive white dwarf stars with oxygen-neon cores. This work is motivated by recent observational evidence about the existence of white dwarf stars with very high surface gravities.…

Astrophysics · Physics 2016-08-16 L. G. Althaus , E. García--Berro , J. Isern , A. H. Córsico

The determination of astrophysical reaction rates requires different approaches depending on the conditions in hydrostatic and explosive burning. The focus here is on astrophysical reaction rates for radiative neutron capture reactions.…

Nuclear Theory · Physics 2022-11-10 Thomas Rauscher

We outline the phenomenon of deep crustal heating in transiently accreting neutron stars. It is produced by nuclear transformations (mostly, by pycnonuclear reactions) in accreted matter while this matter sinks to densities rho > 10^{10}…

Astrophysics · Physics 2007-05-23 D. G. Yakovlev , K. P. Levenfish

The impact of nuclear physics uncertainties on nucleosynthesis in thermonuclear supernovae has not been fully explored using comprehensive and systematic studies with multiple models. To better constrain predictions of yields from these…

Solar and Stellar Astrophysics · Physics 2015-06-16 Anuj Parikh , Jordi Jose , Ivo R. Seitenzahl , Friedrich K. Roepke

One of the challenges to increasing the mass of a white dwarf through accretion is the tendency for the accumulating hydrogen to ignite unstably and potentially trigger mass loss. It has been known for many years that there is a narrow…

Astrophysics · Physics 2011-02-11 Ken J. Shen , Lars Bildsten

Motivated by landscape models in string theory, cosmic nuclear evolution is analyzed allowing the Standard Model Higgs expectation value w to take values different from that in our world (w=1), while holding the Yukawa couplings fixed.…

Astrophysics · Physics 2009-11-11 Craig J. Hogan

Within the theoretical framework of some modern unification theories the constants of nature are functions of cosmological time. White dwarfs offer the possibility of testing a possible variation of G and, thus, to place constraints to…

Solar and Stellar Astrophysics · Physics 2015-05-20 L. G. Althaus , A. H. Corsico , S. Torres , P. Loren-Aguilar , J. Isern , E. Garcia-Berro

The merger of two carbon-oxygen white dwarfs can lead either to a spectacular transient, stable nuclear burning or a massive, rapidly rotating white dwarf. Simulations of mergers have shown that the outcome strongly depends on whether the…

Solar and Stellar Astrophysics · Physics 2015-06-11 Chenchong Zhu , Philip Chang , Marten van Kerkwijk , James Wadsley

This work presents new $^{12}$C + $^{12}$C reaction rates in the form of numerical tables with associated uncertainty estimation, as well as analytical formulae that can be directly implemented into stellar evolution codes. This article…

Solar and Stellar Astrophysics · Physics 2022-04-11 E. Monpribat , S. Martinet , S. Courtin , M. Heine , S. Ekström , D. G. Jenkins , A. Choplin , P. Adsley , D. Curien , M. Moukaddam , J. Nippert , S. Tsiatsiou , G. Meynet

Since the Gaia data release 2, several works were published describing a bifurcation in the observed white dwarf colour$-$magnitude diagram for $\mbox{$G_{\mathrm{BP}}$}-\mbox{$G_{\mathrm{RP}}$} > 0$. Some possible explanations in the…

Solar and Stellar Astrophysics · Physics 2020-02-12 G. Ourique , S. O. Kepler , A. D. Romero , T. S. Klippel , D. Koester

We consider the astrophysical reaction rates for radiative neutron capture reactions ($n,\gamma$) in the crust of a neutron star. The presence of degenerate neutrons at high densities (mainly in the inner crust) can drastically affect the…

Solar and Stellar Astrophysics · Physics 2012-07-26 P. S. Shternin , M. Beard , M. Wiescher , D. G. Yakovlev

We construct time-dependent one-dimensional (vertically averaged) models of accretion disks produced by the tidal disruption of a white dwarf (WD) by a binary neutron star (NS) companion. Nuclear reactions in the disk midplane burn the WD…

High Energy Astrophysical Phenomena · Physics 2016-09-16 Ben Margalit , Brian D. Metzger