We make a comparative study of the neutrinoless double beta decay constraints on heavy sterile neutrinos versus other direct and indirect constraints from both lepton number conserving and violating processes, as a sensitive probe of the extent of lepton number violation and possible interference effects in the sterile sector. We introduce a phenomenological parametrisation of the simplified one-generation seesaw model with one active and two sterile neutrino states in terms of experimentally measurable quantities, such as active-sterile neutrino mixing angles, CP phases, masses and mass splittings. This simple parametrisation enables us to analytically derive a spectrum of possible scenarios between the canonical seesaw with purely Majorana heavy neutrinos and inverse seesaw with pseudo-Dirac ones. We then go on to constrain the simplified parameters of this model from various experiments at the energy, intensity and cosmic frontiers. We emphasise that the constraints from lepton number violating processes strongly depend on the mass splitting between the two sterile states and the relative CP phase between them. This is particularly relevant for neutrinoless double beta decay, which is weakened for small mass splitting and opposite CP parities between the sterile states. On the other hand, neutrinoless double beta decay is especially sensitive for Majorana sterile neutrinos with masses around 0 . 1 − 10 GeV.

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无中微子双β衰变与重无菌中微子的其他探测器

我们对重无菌中微子的无中微子双β衰变约束与来自轻子数守恒和违反过程的其他直接和间接约束进行了比较研究，作为对轻子数违反程度和无菌部门可能的干扰影响的敏感探测. 我们根据实验可测量的量（例如活性-无菌中微子混合角、CP 相、质量和质量分裂）引入了简化的一代跷跷板模型的现象学参数化，该模型具有一个活性和两个惰性中微子状态。这种简单的参数化使我们能够分析地推导出具有纯马约拉纳重中微子的经典跷跷板和具有伪狄拉克中微子的反跷跷板之间的一系列可能情景。然后，我们继续从能量、强度和宇宙前沿的各种实验中约束该模型的简化参数。我们强调轻子数违反过程的约束强烈依赖于两个无菌状态之间的质量分裂和它们之间的相对 CP 阶段。这与无中微子双 β 衰变特别相关，它因小质量分裂和无菌状态之间的相反 CP 奇偶性而减弱。另一方面，无中微子双 β 衰变对质量约为 0 的马约拉纳不育中微子特别敏感。1 - 10 GeV。我们强调轻子数违反过程的约束强烈依赖于两个无菌状态之间的质量分裂和它们之间的相对 CP 阶段。这与无中微子双 β 衰变特别相关，后者因小质量分裂和无菌状态之间的相反 CP 奇偶性而减弱。另一方面，无中微子双 β 衰变对质量约为 0 的马约拉纳不育中微子特别敏感。1 - 10 GeV。我们强调轻子数违反过程的约束强烈依赖于两个无菌状态之间的质量分裂和它们之间的相对 CP 阶段。这与无中微子双 β 衰变特别相关，后者因小质量分裂和无菌状态之间的相反 CP 奇偶性而减弱。另一方面，无中微子双 β 衰变对质量约为 0 的马约拉纳不育中微子特别敏感。1 - 10 GeV。