论文标题
贝叶斯框架中的中子皮和纯中子物质的核对称能量
The nuclear symmetry energy from neutron skins and pure neutron matter in a Bayesian framework
论文作者
论文摘要
我们通过结合CA，PB和SN同位素上的中子皮肤数据以及有关Pure Netron Matter（PNM）的最佳理论信息（PNM）来提出核对称能量幅度$ j $，斜率$ l $和曲率$ k _ {\ rm sym} $的推断。贝叶斯框架用于始终从手性有效野外理论计算中始终合并对状态的PNM方程的先验知识。中子皮是使用扩展的Skyrme能量密度功能以Hartree-fock方法建模的，该功能可以独立变化$ j $，$ l $和$ k _ {\ rm sym} $，而不会影响状态的对称核物质方程。我们讨论了中子皮肤数据集的选择，并结合了正交中的错误，我们获得了95 \％可信的值$ j = 31.3 \ setack {+4.2 \\ -5.9} $ mev，$ l = 40 \ ordack {+34 \\ \ \ \ \ \ \ \ \ \ \ -26} $ MEV和$ K________________ -444 \替代{+100 \\ -84} $ meV使用$ j $，$ l $和$ k _ {\ rm sym} $中的非信息先验，以及$ j = 31.9 \替换-480 \替换{+25 \\ -26} $ MEV使用PNM Priors。讨论了由中子皮肤数据引起的对称能量参数之间的相关性，并将其与液滴模型进行比较。仅仅显示中性皮肤数据就可以对对称能量参数施加限制，就像单独从手性有效场理论获得的参数一样严格，并且当组合95 \％的可信间隔时，将降低4-5倍。在杰斐逊实验室和Mainz超导加速器的平等性电子散射实验中对铅和钙中子皮的新测量之前，我们根据钙的中子皮肤中性皮肤的现有数据进行预测0.167 $ \ pm $ 0.008 fm和$ 0.172 \ pm 0.015 $ fm，使用PNM先验。
We present an inference of the nuclear symmetry energy magnitude $J$, the slope $L$ and the curvature $K_{\rm sym}$ by combining neutron skin data on Ca, Pb and Sn isotopes and our best theoretical information about pure neutron matter (PNM). A Bayesian framework is used to consistently incorporate prior knowledge of the PNM equation of state from chiral effective field theory calculations. Neutron skins are modeled in a Hartree-Fock approach using an extended Skyrme energy-density functional which allows for independent variation of $J$, $L$ and $K_{\rm sym}$ without affecting the symmetric nuclear matter equation of state. We discuss the choice of neutron skin data sets, and combining errors in quadrature we obtain 95\% credible values of $J=31.3\substack{+4.2 \\ -5.9}$ MeV, $L=40\substack{+34 \\ -26}$ MeV and $K_τ = L - 6K_{\rm sym}= -444\substack{+100 \\ -84}$ MeV using uninformative priors in $J$, $L$ and $K_{\rm sym}$, and $J=31.9\substack{+1.3 \\ -1.3}$ MeV, $L=37\substack{+9 \\ -8}$ MeV and $K_τ = -480\substack{+25 \\ -26}$ MeV using PNM priors. The correlations between symmetry energy parameters induced by neutron skin data is discussed and compared with the droplet model. Neutron skin data alone is shown to place limits on the symmetry energy parameters as stringent as those obtained from chiral effective field theory alone, and when combined the 95\% credible intervals are reduced by a factor of 4-5. Ahead of new measurements of lead and calcium neutron skins from parity-violating electron scattering experiments at Jefferson Lab and Mainz Superconducting Accelerator, we make predictions based on existing data on neutron skins of tin for the neutron skins of calcium and lead of 0.166$\pm$0.008 fm and $0.169 \pm 0.014$ fm respectively, using uninformative priors, and 0.167$\pm$0.008 fm and $0.172 \pm 0.015$ fm respectively, using PNM priors.
