标题： 超新星前中微子在TQRPA方法框架下的研究 显示英文标题

标题： Neutrinos from pre-supernova in the framework of TQRPA method

摘要： 我们提出了一种计算超新星前环境中由弱过程产生的（反）中微子谱和亮度的新方法。该方法基于热准粒子随机相位近似（TQRPA），允许微观且热力学一致地计算有限温度下原子核的弱相互作用响应。对于来自恒星演化代码MESA的现实代表性超新星前条件，我们计算了由热$^{56}$铁与中性及带电电流弱反应产生的（反）中微子亮度和谱，并将其与热过程的贡献进行比较。我们发现，与基于大尺度壳模型（LSSM）弱相互作用速率的标准技术相比，TQRPA方法不仅产生了更高的电子中微子总亮度（主要来源于电子俘获反应），还具有更硬的中微子谱。此外，应用TQRPA和LSSM，我们发现，在电子反中微子生成的背景下，中性电流核去激发（ND）过程通过中微子-反中微子对发射至少与电子-正电子对湮灭过程同样重要。我们还表明，味振荡增强了ND过程对电子反中微子流的高能贡献。这可能对地球探测器在超新星前反中微子注册方面具有潜在的重要性。 显示英文摘要

摘要： We propose a new method for calculating spectra and luminosities for (anti)neutrinos produced in the pre-supernova environment by weak processes with hot nuclei. It is based on the thermal quasiparticle random phase approximation (TQRPA), that allows microscopic thermodynamically consistent calculations of the weak-interaction response of nuclei at finite temperatures. For realistic representative pre-supernova conditions from the stellar evolution code MESA, we compute (anti)neutrino luminosities and spectra arising from neutral- and charged-current weak reactions with hot $^{56}$Fe and compare them with the contribution of thermal processes. We find that the TQRPA approach produces not only a higher total luminosity of electron neutrinos (mainly born in the electron capture reaction), compared to the standard technique based on the large-scale shell model (LSSM) weak-interaction rates, but also a harder neutrino spectrum. Besides, applying the TQRPA and LSSM, we find that in the context of electron antineutrino generation, the neutral-current nuclear de-excitation (ND) process via neutrino-antineutrino pair emission is at least as important as the electron-positron pair annihilation process. We also show that flavor oscillations enhance the high-energy contribution of the ND process to the electron antineutrino flux. This could potentially be important for pre-supernova antineutrino registration by the Earth's detectors.