论文标题
用轴的F（R）重力中的中子星旋转
Rotating Neutron Stars in F(R) Gravity with Axions
论文作者
论文摘要
我们研究了$ r^2 $重力中均匀旋转中子星的平衡构型，用于核物质的GM1状态方程（EOS）。与静态恒星相比，对某些频率提出了质量 - 拉迪乌斯图，质量中央能量密度。我们还计算恒星的赤道和极性半径以及惯性矩。对于Axion字段$ ϕ $，假定$ \ sim r^2ϕ $的耦合。我们的考虑取得了一些有趣的结果。由于耦合项的贡献，最大可能的恒星质量增加了EOS。我们发现与一般相对论相比，有可能增加旋转的最大频率。结果，快速旋转恒星的质量下限减小。对于频率$ f = 700 $ hz中子星，带有质量$ \ sim m_ \ odot $作为某种选择的参数可能存在（在同一eos的一般相对论中，此限制此限制约为$ 1.2 m _ {\ odot} $）。我们溶液的另一个特征是，与静态情况相比，高频相比，恒星半径相对较小。因此，最终发现了$ r^2 $带有轴的新的中子星，即带有中间质量的快速旋转紧凑型恒星。
We investigate equilibrium configurations of uniformly rotating neutron stars in $R^2$ gravity with axion scalar field for GM1 equation of state (EoS) for nuclear matter. The mass-radius diagram, mass-central energy density are presented for some frequencies in comparison with static stars. We also compute equatorial and polar radii and moment of inertia for stars. For axion field $ϕ$ the coupling in the form $\sim R^2ϕ$ is assumed. Several interesting results follow from our consideration. Maximal possible star mass with given EoS increases due to the contribution of coupling term. We discovered the possibility to increase maximal frequency of the rotation in comparison with General Relativity. As a consequence the lower bound on mass of the fast rotating stars decreases. For frequency $f=700$ Hz neutron stars with masses $\sim M_\odot$ can exist for some choice of parameters (in General Relativity for same EoS this limit is around $1.2 M_{\odot}$). Another feature of our solutions is relatively small increase of stars radii for high frequencies in comparison with static case. Thus, eventually the new class of neutron stars in $R^2$ gravity with axions is discovered namely fast rotating compact stars with intermediate masses.
