Uncertainties in the pasta-phase properties of catalysed neutron stars

Autor: T. Carreau, H. Dinh Thi, Francesca Gulminelli, Anthea Fantina
Přispěvatelé: Laboratoire de physique corpusculaire de Caen (LPCC), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Grand Accélérateur National d'Ions Lourds (GANIL), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)
Rok vydání: 2021
Předmět:
Zdroj: Astronomy and Astrophysics-A&A
Astronomy and Astrophysics-A&A, 2021, 654, pp.A114. ⟨10.1051/0004-6361/202141192⟩
Astron.Astrophys.
Astron.Astrophys., 2021, 654, pp.A114. ⟨10.1051/0004-6361/202141192⟩
Astronomy and Astrophysics
Astronomy and Astrophysics, EDP Sciences, 2021, 654, pp.A114. ⟨10.1051/0004-6361/202141192⟩
ISSN: 0004-6361
1432-0746
DOI: 10.48550/arxiv.2109.13638
Popis: The interior of a neutron star is expected to exhibit different states of matter. In particular, complex non-spherical configurations known as `pasta' phases may exist at the highest densities in the inner crust, potentially having an impact on different neutron-star phenomena. We study the properties of the pasta phase and the uncertainties in the pasta observables which are due to our incomplete knowledge of the nuclear energy functional. To this aim, we employed a compressible liquid-drop model approach with surface parameters optimised either on experimental nuclear masses or theoretical calculations. To assess the model uncertainties, we performed a Bayesian analysis by largely varying the model parameters using uniform priors, and generating posterior distributions with filters accounting for both our present low-density nuclear physics knowledge and high-density neutron-star physics constraints. Our results show that the nuclear physics constraints, such as the neutron-matter equation of state at very low density and the experimental mass measurements, are crucial in determining the crustal and pasta observables. Accounting for all constraints, we demonstrate that the presence of pasta phases is robustly predicted in an important fraction of the inner crust. We estimate the relative crustal thickness associated with pasta phases as $R_{\rm pasta}/R_{\rm crust}=0.128\pm 0.047$ and the relative moment of inertia as $I_{\rm pasta}/I_{\rm crust}=0.480\pm 0.137$. Our findings indicate that the surface and curvature parameters are more influential than the bulk parameters for the description of pasta observables. We also show that using a surface tension that is inconsistent with the bulk functional leads to an underestimation of both the average values and the uncertainties in the pasta properties, thus highlighting the importance of a consistent calculation of the nuclear functional.
Comment: 12 pages, 8 figures, accepted for publication in Astronomy and Astrophysics. Typos corrected
Databáze: OpenAIRE
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