The electron capture process plays an important role in the evolution of the core collapse of a massive star that precedes the supernova explosion. In this study, the electron capture on nuclei in stellar environment is described in the relativistic energy density functional framework, including both the finite temperature and nuclear pairing effects. Relevant nuclear transitions $J^{\pi }=0^{\pm },1^{\pm },2^{\pm }$ are calculated using the finite temperature proton-neutron quasiparticle random phase approximation with the density-dependent meson-exchange effective interaction DD-ME2. The pairing and temperature effects are investigated in the Gamow-Teller transition strength as well as the electron capture cross sections and rates for ${}^{44}$Ti and ${}^{56}$Fe in stellar environment. It is found that the pairing correlations establish an additional unblocking mechanism similar to the finite temperature effects, that can allow otherwise blocked single-particle transitions. Inclusion of pairing correlations at finite temperature can significantly alter the electron capture cross sections, even up to a factor of two for ${}^{44}$Ti, while for the same nucleus electron capture rates can increase by more than one order of magnitude. We conclude that for the complete description of electron capture on nuclei both pairing and temperature effects must be taken into account.

中文翻译：

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基于有限温度相对论拟粒子随机相近似的恒星电子捕获率

电子捕获过程在超新星爆炸之前的大质量恒星核心坍缩的演化中起着重要作用。在这项研究中，相对论能量密度功能框架描述了恒星环境中核子上的电子捕获，包括有限温度和核对效应。相关的核转型${Ĵ}^{\pi }=0^{\pm }，{\mathrm{1个}}^{\pm }，2^{\pm }$使用有限温度的质子-中子准粒子随机相位近似和依赖于密度的介子交换有效相互作用DD-ME2来计算。研究了配对和温度效应的Gamow-Teller转变强度以及电子俘获截面和速率${}^{44}$钛和 ${}^{56}$在恒星环境中的铁。发现配对相关建立了类似于有限温度效应的另外的解除阻塞机制，该机制可以允许否则阻塞的单粒子转变。在有限的温度下包含配对相关性可以显着改变电子俘获截面，即使对于${}^{44}$钛，而对于相同的原子核，电子捕获速率可以增加一个数量级以上。我们得出结论，为了完整描述核上的电子捕获，必须同时考虑配对和温度效应。