论文标题
163HO的电子捕获频谱的从头算计算：螺旋体 - 增长剂腐烂到连续状态
Ab initio calculation of the electron capture spectrum of 163Ho: Auger-Meitner decay into continuum states
论文作者
论文摘要
通过$^{163} $ ho来确定电子中微子质量，取决于对差异电子捕获核衰减速率的准确理解，这是中微子和电子激发之间总衰减能的分布的函数。由于局部原子多重态带有核心孔的局部原子多重态，所得频谱由共振主导。电子之间的库仑散射将离散的原子态通过螺旋杆 - 米特纳衰减与自由电子的最终状态。原子多重组在自动离世能量之上，因此代表这些离散水平的三角洲函数变成了洛伦兹，马汉和类似Fano的线形形状的叠加。我们提出了一种\ textit {ab intio}方法，用于计算由于此类过程而导致的核衰减修饰。它包括与未结合的螺旋螺旋体 - 增强剂电子相互作用的局部原子轨道中有多个相关孔的状态。发现与最近实验的强烈能量依赖性，不对称的拓宽相吻合。我们对确定最终光谱线形状的机制进行了详细的分析，并讨论了不同共振之间的FANO干扰以及螺旋杆 - 甲板库仑基质元素的能量依赖性。后一种机制被证明是负责$^{163} $ HO的电子捕获光谱中共振的不对称线形状的主要通道。
Determining the electron neutrino mass by electron capture in $^{163}$Ho relies on an accurate understanding of the differential electron capture nuclear decay rate as a function of the distribution of the total decay energy between the neutrino and electronic excitations. The resulting spectrum is dominated by resonances due to local atomic multiplet states with core holes. Coulomb scattering between electrons couple the discrete atomic states, via Auger-Meitner decay, to final states with free electrons. The atomic multiplets are above the auto-ionisation energy, such that the delta functions representing these discrete levels turn into a superposition of Lorentzian, Mahan- and Fano-like line-shapes. We present an \textit{ab initio} method to calculate nuclear decay modifications due to such processes. It includes states with multiple correlated holes in local atomic orbitals interacting with unbound Auger-Meitner electrons. A strong energy-dependent, asymmetric broadening of the resonances in good agreement with recent experiments is found. We present a detailed analysis of the mechanisms determining the final spectral line-shape and discuss both the Fano interference between different resonances, as well as the energy dependence of the Auger-Meitner Coulomb matrix elements. The latter mechanism is shown to be the dominant channel responsible for the asymmetric line-shape of the resonances in the electron capture spectrum of $^{163}$Ho.
