English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The symmetry energy and its density dependence are pivotal for many nuclearphysics and astrophysics applications, as they determine properties rangingfrom the neutron-skin thickness of nuclei to the crust thickness and the radiusof neutron stars. Recently, PREX-II reported a value of $0.283\pm0.071$ fm forthe neutron-skin thickness of $^{208}$Pb, $R_{\rm skin}^{^{208}\text{Pb}}$,implying a symmetry-energy slope parameter $L$ of $106\pm37$ MeV, larger thanmost ranges obtained from microscopic calculations and other nuclearexperiments. We use a nonparametric equation of state representation based onGaussian processes to constrain the symmetry energy $S_0$, $L$, and $R_{\rmskin}^{^{208}\text{Pb}}$ directly from observations of neutron stars withminimal modeling assumptions. The resulting astrophysical constraints fromheavy pulsar masses, LIGO/Virgo, and NICER favor smaller values of the neutronskin and $L$, as well as negative symmetry incompressibilities. Combiningastrophysical data with chiral effective field theory ($\chi$EFT) and PREX-IIconstraints yields $S_0 = 33.0^{+2.0}_{-1.8}$ MeV, $L=53^{+14}_{-15}$ MeV, and$R_{\rm skin}^{^{208}\text{Pb}} = 0.17^{+0.04}_{-0.04}$ fm. We also examine theconsistency of several individual $\chi$EFT calculations with astrophysicalobservations and terrestrial experiments. We find that there is only mildtension between $\chi$EFT, astrophysical data, and PREX-II's$R_\mathrm{skin}^{^{208}\mathrm{Pb}}$ measurement ($p$-value $= 12.3\%$) andthat there is excellent agreement between $\chi$EFT, astrophysical data, andother nuclear experiments.

A Detailed Examination of Astrophysical Constraints on the Symmetry Energy and the Neutron Skin of $^{208}$Pb with Minimal Modeling Assumptions