发表机构
Jeonbuk National University; Harish-Chandra Research Institute; Homi Bhabha National Institute; Institute for Basic Science; Korea Institute for Advanced Study; Kyungpook National University（全北国立大学; 哈里什-昌德拉研究所; 霍米·巴巴国立研究所; 韩国基础科学研究院; 韩国高等研究院; 庆北国立大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究在三活性味框架下探讨太阳中微子自旋-味进动，发现非共振马约拉纳转换可产生独特的太阳反中微子信号，金坪实验有望以高灵敏度探测马约拉纳跃迁磁矩。
AI 中文摘要
我们在三活性味框架下研究了由磁矩引起的太阳中微子自旋-味进动（SFP）。对于马约拉纳中微子，SFP可以将太阳中微子转换为不同活性味的反中微子。在狄拉克情形下，SFP转而产生惰性右旋态，并可能导致活性中微子的消失。利用完整的$6\times6$哈密顿量以及GS98和AGSS09太阳剖面，我们研究了在$B_\perp=0$处的传播本征值交叉以及相应状态之间的投影磁耦合。对于正常质量顺序和$1\leq E_\nu/\mathrm{MeV}\leq20$，我们确认了有限密度马约拉纳交叉的缺失。一个磁耦合的狄拉克交叉出现在约$12~\mathrm{MeV}$以上，但仅涉及亚主导的电子味分量，限制了共振消失。然而，非共振马约拉纳转换提供了一种独特的违反轻子数的太阳$\bar\nu_e$信号，这促使我们对金坪中微子实验的灵敏度进行研究。对于拟议的$3~\mathrm{kt}$探测器运行五到十年，我们预计90%置信水平的灵敏度为$P(\nu_e\to\bar\nu_e)\simeq(0.85-1.3)\times10^{-5}$。在仅考虑$\mu_{12}$的基准情形下，乐观的太阳核心横向磁场$B_\perp=7-10~\mathrm{MG}$意味着$|\mu_{12}|\simeq(2.3-4.1)\times10^{-13}\\,\mu_B$的探测范围，数值上低于现有的直接散射限制和通常引用的恒星冷却界限。这可能使金坪实验成为对马约拉纳跃迁磁矩最具竞争力的预期地面灵敏度之一。
英文摘要
We investigate solar-neutrino spin--flavor precession (SFP) induced by magnetic moments in the three-active-flavor framework. For Majorana neutrinos, SFP can convert solar neutrinos into antineutrinos of different active flavors. In the Dirac case, SFP instead produces sterile right-handed states and can lead to the disappearance of active neutrinos. Using the full $6\times6$ Hamiltonians and GS98 and AGSS09 solar profiles, we examine propagation-eigenvalue crossings at $B_\perp=0$ and the projected magnetic couplings between the corresponding states. For normal mass ordering and $1\leq E_ν/\mathrm{MeV}\leq20$, we confirm the absence of finite-density Majorana crossings. A magnetically coupled Dirac crossing emerges above approximately $12~\mathrm{MeV}$ but involves only a subdominant electron-flavor component, limiting resonant disappearance. Nonresonant Majorana conversion nevertheless offers a distinctive lepton-number-violating solar $\barν_e$ signal, motivating our sensitivity study for the Jinping Neutrino Experiment. For a proposed $3~\mathrm{kt}$ detector operating for five to ten years, we project a 90\% C.L. sensitivity of $P(ν_e\to\barν_e)\simeq(0.85-1.3)\times10^{-5}$. In the $μ_{12}$-only benchmark, optimistic solar-core transverse magnetic fields of $B_\perp=7-10~\mathrm{MG}$ imply a reach of $|μ_{12}|\simeq(2.3-4.1)\times10^{-13}\,μ_B$, numerically below existing direct-scattering limits and commonly quoted stellar-cooling bounds. This could enable Jinping to provide one of the most stringent projected terrestrial sensitivities to Majorana transition magnetic moments.
Comments26 pages, 7 figures
