论文标题
部分可观测时空混沌系统的无模型预测
Revisiting pseudo-Dirac neutrino scenario after recent solar neutrino data
论文作者
论文摘要
储层计算是预测湍流的有力工具，其简单的架构具有处理大型系统的计算效率。然而，其实现通常需要完整的状态向量测量和系统非线性知识。我们使用非线性投影函数将系统测量扩展到高维空间，然后将其输入到储层中以获得预测。我们展示了这种储层计算网络在时空混沌系统上的应用，该系统模拟了湍流的若干特征。我们表明，使用径向基函数作为非线性投影器，即使只有部分观测并且不知道控制方程，也能稳健地捕捉复杂的系统非线性。最后，我们表明，当测量稀疏、不完整且带有噪声，甚至控制方程变得不准确时，我们的网络仍然可以产生相当准确的预测，从而为实际湍流系统的无模型预测铺平了道路。
It is still unknown whether the mass terms for neutrinos are of Majorana type or of Dirac type. An interesting possibility, known as pseudo-Dirac scheme combines these two with a dominant Dirac mass term and a subdominant Majorana one. As a result, the mass eigenstates come in pairs with a maximal mixing and a small splitting determined by the Majorana mass. This will affect the neutrino oscillation pattern for long baselines. We revisit this scenario employing recent solar neutrino data, including the seasonal variation of the $^7$Be flux recently reported by BOREXINO. We constrain the splitting using these data and find that both the time integrated solar neutrino data and the seasonal variation independently point towards a new pseudo-Dirac solution with nonzero splitting for $ν_2$ of $Δm_2^2\simeq 1.5\times 10^{-11}$ eV$^2$. We propose alternative methods to test this new solution. In particular, we point out the importance of measuring the solar neutrino flux at the intermediate energies $1.5~{\rm MeV}<E_ν<3.5~{\rm MeV}$ (below the Super-Kamiokande detection threshold) as well as a more precise measurement of the $pep$ flux. The code is available on \href{https://github.com/SaeedAnsarifard/SolarNeutrinos-pseudoDirac.git}{Github}
