Nuclear Physics of the Outer Layers of Accreting Neutron Stars

Abstract

Now 50 years since the existence of the neutron star crust was proposed, we review the current understanding of the nuclear physics of the outer layers of accreting neutron stars. Nuclei produced during nuclear burning replace the nascent composition of the neutron star ocean and crust. Non-equilibrium nuclear reactions driven by compression alter the outer thermal structure and chemical composition, leaving observable imprints on astronomical phenomena. As observations of bursting neutron stars and cooling neutron stars have increased, the recent volume of astronomical data allows new insights into the microphysics of the neutron star interior and the possibility to test nuclear physics input in model calculations. Despite numerous advances in our understanding of neutron star interiors and observed neutron star phenomena, many challenges remain in the astrophysics theory of accreting neutron stars, the nuclear theory of neutron-rich nuclei, and the reach and precision of terrestrial nuclear physics experiments.

arXiv commentInvited review to appear in Journal of Physics G (70 pages)

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Cited by in corpus (58)

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• Influence of Nuclear Reaction Rate Uncertainties on Neutron Star Properties Extracted From X-ray Burst Model-Observation Comparisons
• Horizons: Nuclear Astrophysics in the 2020s and Beyond
• Thermal evolution and quiescent emission of transiently accreting neutron stars
• Heat blanketing envelopes of neutron stars
• Crystallization of the outer crust of a non-accreting neutron star
• Nuclear Mass Measurements Map the Structure of Atomic Nuclei and Accreting Neutron Stars
• Crust structure and thermal evolution of neutron stars in soft X-ray transients
• Thermodynamically consistent equation of state for an accreted neutron star crust
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• Urca Cooling in Neutron Star Crusts and Oceans: Effects of Nuclear Excitations
• Heat release in accreting neutron stars
• Experimental constraints on shallow heating in accreting neutron-star crusts
• Deep crustal heating for realistic compositions of thermonuclear ashes
• Constraining the Neutron Star Compactness: Extraction of the ${}^{23}$Al($p,\gamma$) Reaction Rate for the $rp$-Process
• Experimentally well-constrained masses of ${}^{27}$P and ${}^{27}$S: Implications for studies of explosive binary systems
• Crust of accreting neutron stars within simplified reaction network
• $\beta$-decay of ${}^{61}$V and its Role in Cooling Accreted Neutron Star Crusts
• Simulating the shock dynamics of a neutron star accretion column
• The efficiency of nuclear burning during thermonuclear (Type I) bursts as a function of accretion rate
• The Regulated NiCu Cycles with the new ${}^{57}$Cu(p,$\gamma$)${}^{58}$Zn reaction rate and the Influence on Type-I X-Ray Bursts: GS 1826$-$24 Clocked Burster
• Neutron transfer reactions in accreting neutron stars
• Study of the ${}^{22}$Mg waiting point relevant for x-ray burst nucleosynthesis via the ${}^{22}$Mg($\alpha$,$p$)${}^{25}$Al reaction
• Crucial role of neutron diffusion in the crust of accreting neutron stars
• Gapless neutron superfluidity can explain the late time cooling of transiently accreting neutron stars
• Accreting neutron stars: heating of the upper layers of the inner crust
• Partially accreted crusts of neutron stars
• Multi-messenger Emission from Tidal Waves in Neutron Star Oceans
• Accreting neutron stars from the nuclear energy-density functional theory. II. Equation of state and global properties
• Black Dwarf Supernova in the Far Future
• The Impact of Neutron Transfer Reactions on Heating and Cooling of Accreted Neutron Star Crusts
• First direct measurement constraining the ${}^{34}$Ar($\alpha$,p)${}^{37}$K reaction cross section for mixed hydrogen and helium burning in accreting neutron stars
• Crust Cooling Models are Insensitive to the Crust-Core Transition Pressure for Realistic Equations of State
• Nonequilibrium thermodynamics of accreted neutron-star crust
• The outer crust of a cold, non-accreting neutron star within the Quark-Meson Coupling (QMC) model
• Determination of the ${}^{60}$Zn level density from neutron evaporation spectra
• Impact of Pycnonuclear Fusion Uncertainties on the Cooling of Accreting Neutron Star Crusts
• Improved Nuclear Physics Near $A=61$ Refines Urca Neutrino Luminosities in Accreted Neutron Star Crusts
• High-precision mass measurement of ${}^{24}$Si and a refined determination of the $rp$ process at the $A=22$ waiting point
• Mapping the frontiers of the nuclear mass surface
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• Capture Rates of Highly Degenerate Neutrons
• A solution to the tension of burning on neutron stars and nuclear physics
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• Layers of electron captures in the crust of accreting neutron stars
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