无中微子双β衰变为何能证明中微子是马约拉纳粒子？
Why would neutrinoless double-beta decay prove neutrinos are Majorana particles?
普通双β衰变放出两个中微子；若发生无中微子版本，说明中微子是自己湮灭自己的反粒子（马约拉纳型），并暗示轻子数不守恒，对解释物质起源意义重大。
Normal double-beta decay emits two neutrinos; a neutrinoless version means the neutrino is its own antiparticle (Majorana) and lepton number is violated, bearing on why matter dominates.
难度 专业 · 适合 小学高段(9-12)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Schechter 与 Valle，《SU(2)xU(1) 理论中的无中微子双β衰变》，Physical Review Letters 45 (1980)
Schechter & Valle, 'Neutrinoless Double Beta Decay in SU(2)xU(1) Theories', Physical Review Letters 45 (1980)
#无中微子双β #马约拉纳 #轻子数
超级神冈探测器是如何利用向上与向下大气中微子穿越路程的长短差异，坐实μ型中微子振荡的？
How did Super-Kamiokande exploit the difference in flight paths between upward- and downward-going atmospheric neutrinos to clinch the case for muon-neutrino oscillation?
宇宙线簇射产生的大气中微子里μ型与电子型的比值理论上约为2，并且几乎不随天顶角改变。超级神冈却观测到：向上穿行上万公里的μ型事例明显少于向下仅走几十公里的同类事例，且畸变幅度随L/Eν增大而加深。这种上下不对称只有μ型中微子在飞行中消失为探测不到的味态才能解释，振荡拟合给出Δm²约2.2×10⁻³ eV²和大混合角。
Atmospheric showers should deliver roughly twice as many muon-flavor as electron-flavor neutrinos with almost no dependence on zenith angle. Super-Kamiokande instead counted far fewer upward muon events crossing ten thousand kilometers than downward ones traveling only tens of kilometers, and the suppression deepened as L/Eν grew. Only the disappearance of muon neutrinos into an undetected flavor explains the up-down asymmetry, with oscillation fits yielding Δm² near 2.2×10⁻³ eV² and a large mixing angle.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Y. Fukuda等，Super-Kamiokande合作组，《Physical Review Letters》81卷1562页（1998）
Y. Fukuda et al., Super-Kamiokande Collaboration, Physical Review Letters 81, 1562 (1998)
#大气中微子 #真空振荡
中微子为什么有“味”又会“振荡”？
Why do neutrinos have flavors and oscillate?
中微子有三种味（电子、μ、τ），它们在飞行中会互相转换，这叫中微子振荡，说明它们有微小质量——这已超出标准模型的原始设定。
Neutrinos come in three flavors that morph into one another as they travel, a process called oscillation that proves they have tiny masses beyond the original Standard Model.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Super-Kamiokande 合作组，《大气中微子振荡的证据》，Physical Review Letters 81 (1998)
Super-Kamiokande Collaboration, 'Evidence for Oscillation of Atmospheric Neutrinos', Physical Review Letters 81 (1998)
独立核验依据 · Independent verification: 核验依据 1 ARCHIVE 标识 arxiv-hep-ex9807003：Evidence for oscillation
#中微子振荡 #味 #质量
中微子的“质量顺序”为什么这么难定？
Why is the neutrino mass ordering so hard to pin down?
振荡实验只测出质量平方差，不知道最轻的是哪一代；正常层级与倒置层级要靠更精密的反应堆与加速器中微子实验来裁决。
Oscillation data give only mass-squared differences, not which generation is lightest; telling normal from inverted ordering needs finer reactor and accelerator experiments.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-05 · 4 条独立证据
来源 · Source
粒子数据组（Particle Data Group），《粒子物理学评论》，Progress of Theoretical and Experimental Physics (2022)
Particle Data Group, 'Review of Particle Physics', Progress of Theoretical and Experimental Physics (2022)
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL44253297W：Review of particle phy · 核验依据 3 ARCHIVE 标识 Review_of_Particle_Physics：Review of Particle
#中微子质量 #层级 #振荡
早期的太阳中微子实验测得电子中微子通量只有标准太阳模型预言的三分之一左右，造成这一亏缺的根本原因是什么？
Early solar neutrino experiments recorded an electron-neutrino flux of only about one third of the standard solar model prediction — what is the root cause of this deficit?
根本原因是中微子振荡：太阳核心产生的电子中微子在向外传播途中，穿过物质密度梯度时部分转变为μ子与τ子味，而早期探测器只对电子味敏感。萨德伯里中微子观测站用重水靶同时测量带电流与中性电流反应，证实总通量与理论相符，改变的只是味的构成。这一发现直接确立了中微子质量非零的事实。
Oscillations are the cause: electron neutrinos produced in the solar core partially convert into muon and tau flavors while traversing the density gradient of solar matter, and early detectors responded only to the electron flavor. The Sudbury Neutrino Observatory used heavy water to measure charged-current and neutral-current reactions simultaneously, showing that the total flux matches theory while only the flavor composition shifts. The result established directly that neutrinos have nonzero mass.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
SNO 合作组发表于 Physical Review Letters 87, 071301（2001）的中微子味测量论文
SNO Collaboration, measurement of neutral-current solar neutrino flux, Physical Review Letters 87, 071301 (2001)
#中微子振荡 #太阳中微子
太阳中微子失踪之谜为什么最终被判定为中微子振荡，而不是太阳模型算错了？
Why was the missing solar neutrino puzzle ultimately attributed to neutrino oscillation rather than to errors in the solar model?
Homestake等氯氩实验几十年间只记录到标准太阳模型预言约三分之一的电子型中微子通量。SNO重水探测器用带电流通道单独测电子型、用中性电流通道测全部味道的总和，发现抵达地球前相当一部分已转化为μ或τ型，而总通量与预言一致。味转化源于中微子质量本征态与弱作用本征态不重合，模型本身并无问题。
Chlorine-argon experiments such as Homestake recorded only about a third of the electron-neutrino flux predicted by the standard solar model over decades. The SNO heavy-water detector probed electron flavor alone via charged currents and all flavors together via neutral currents, revealing that a sizable fraction had converted to muon or tau types in transit while the total flux matched predictions. Flavor change stems from neutrino mass eigenstates differing from weak-interaction eigenstates, vindicating the model itself.
难度 进阶 · 适合 大众
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Q.R. Ahmad 等，SNO合作组，《Physical Review Letters》87卷071301（2001）
Q.R. Ahmad et al., SNO Collaboration, Physical Review Letters 87, 071301 (2001)
#中微子振荡 #太阳中微子
中微子是一种什么样的“小幽灵”？
What kind of little ghost is a neutrino?
中微子是一种几乎不和其他东西碰撞的极小粒子，能轻松穿过整个地球而你完全感觉不到。
A neutrino is a tiny particle that almost never bumps into anything, so it can pass through the whole Earth unnoticed.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
Fermi，《β射线理论之尝试》，Zeitschrift fur Physik 88 (1934)
Fermi, 'Versuch einer Theorie der beta-Strahlen', Zeitschrift fur Physik 88 (1934)
#中微子 #基本粒子 #穿透