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arXiv · 1004.5197

Nuclear symmetry energy and core-crust transition in neutron stars: a critical study

Camille Ducoin·Jérôme Margueron·Constança Providencia
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Abstract

The slope of the nuclear symmetry energy at saturation density $L$ is pointed out as a crucial quantity to determine the mass and width of neutron-star crusts. This letter clarifies the relation between $L$ and the core-crust transition. We confirm that the transition density is soundly correlated with $L$ despite differences between models, and we propose a clear understanding of this correlation based on a generalised liquid drop model. Using a large number of nuclear models, we evaluate the dispersion affecting the correlation between the transition pressure $P_t$ and $L$. From a detailed analysis it is shown that this correlation is weak due to a cancellation between different terms. The correlation between the isovector coefficients $K_{\rm sym}$ and $L$ plays a crucial role in this discussion.

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Camille Ducoin, Jérôme Margueron, Constança Providencia. 2010-09-07. Nuclear symmetry energy and core-crust transition in neutron stars: a critical study. https://doi.org/10.1209/0295-5075%2F91%2F32001

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