--- title: "Neutrinos: a worldwide search | Sandbox Physics" description: "From reactor coincidences to the Sun, supernovae and Antarctic ice: follow the instruments, collaborations and arguments that made neutrinos observable." canonical_url: "https://sandboxphysics.com/stories/neutrinos/" language: "en" page_type: "story" alternate_languages: zh-CN: "https://sandboxphysics.com/zh/stories/neutrinos/" last_modified: "2026-10-22" --- A history of the evidence # Neutrinos: a worldwide search From reactor coincidences to the Sun, supernovae and Antarctic ice: follow the instruments, collaborations and arguments that made neutrinos observable. [Understand the prize](https://sandboxphysics.com/stories/neutrinos/nobel-physics-2026/) [Explore the world atlas →](https://sandboxphysics.com/stories/neutrinos/atlas/) Try the experiments Follow the argument ## Choose a question to follow Start with the award or with a scientific question. Each path runs from an early puzzle to the experiments that tested it. ### Start with the prize [01 2026 Nobel Prize in Physics: why look for neutrinos in Antarctic ice? How can a block of ice work as a telescope?](https://sandboxphysics.com/stories/neutrinos/nobel-physics-2026/) [02 What can a neutrino tell us that light cannot? If we already have telescopes, why build a neutrino observatory?](https://sandboxphysics.com/stories/neutrinos/high-energy-neutrinos-astronomy-window/) [03 A huge detector, a few events: reading neutrino scales How can one neutrino be energetic while its detector still needs years of data?](https://sandboxphysics.com/stories/neutrinos/neutrino-energy-distance-and-counts/) [04 How does a faint signal become a neutrino discovery? What must be checked between a sensor flash and a claim about the universe?](https://sandboxphysics.com/stories/neutrinos/neutrino-discovery-evidence-chain/) [05 Read IceCube’s discovery paper, one figure at a time What does each figure actually establish?](https://sandboxphysics.com/stories/neutrinos/icecube-original-paper-figure-guide/) [06 Five ways a neutrino headline can lead us astray What should “seeing a neutrino” mean in a report about this year’s prize?](https://sandboxphysics.com/stories/neutrinos/neutrino-nobel-common-misconceptions/) [07 Francis Halzen and the team that turned Antarctic ice into a telescope How do you turn an idea for a telescope into an instrument people can trust?](https://sandboxphysics.com/stories/neutrinos/halzen-and-collaboration/) [08 Why do neutrinos keep appearing in the Nobel Prize? What was different about each discovery?](https://sandboxphysics.com/stories/neutrinos/neutrinos-and-nobel-prizes/) ### From missing energy to a new particle [09 Where did the energy go? The puzzle that led to the neutrino Why did a spread of electron energies put energy conservation in doubt?](https://sandboxphysics.com/stories/neutrinos/beta-decay-missing-energy/) [10 Pauli’s letter: proposing a particle no one had seen What did Pauli actually propose, and what still had to be established?](https://sandboxphysics.com/stories/neutrinos/pauli-neutrino-letter/) [11 Fermi’s next question: how often should the unseen particle appear? How does an unseen particle become part of a theory that experiments can test?](https://sandboxphysics.com/stories/neutrinos/fermi-beta-decay-theory/) [12 Cowan and Reines: finding the neutrino in two flashes How do you recognize a neutrino interaction among all the other signals in a detector?](https://sandboxphysics.com/stories/neutrinos/reactor-first-detection/) ### Tell the particle families apart [13 Why did physicists need a second kind of neutrino? How can the particle left in a detector tell us which neutrino arrived?](https://sandboxphysics.com/stories/neutrinos/brookhaven-muon-neutrino/) [14 Gargamelle: what if a neutrino interacted and stayed a neutrino? How do you identify an interaction when the outgoing neutrino also goes unseen?](https://sandboxphysics.com/stories/neutrinos/gargamelle-neutral-currents/) [15 LEP: counting particles that leave no trace How can the shape of a collision-energy peak count invisible decay channels?](https://sandboxphysics.com/stories/neutrinos/lep-light-neutrinos/) [16 DONUT: catching a tau before it disappears What made four events persuasive evidence for a third neutrino flavor?](https://sandboxphysics.com/stories/neutrinos/donut-tau-neutrino/) ### What happened to the Sun’s neutrinos? [17 Which reactions in the Sun make neutrinos? Why can a rare solar reaction dominate the events in a detector?](https://sandboxphysics.com/stories/neutrinos/solar-fusion-neutrino-sources/) [18 The Sun’s missing neutrinos: a tank, a calculation and a long disagreement When a detector counts fewer particles than a solar model predicts, which part of the explanation should change?](https://sandboxphysics.com/stories/neutrinos/homestake-solar-neutrino-problem/) [19 Gallium experiments: opening the Sun’s low-energy window What can an experiment learn when it counts atoms instead of individual light flashes?](https://sandboxphysics.com/stories/neutrinos/gallium-low-energy-solar-neutrinos/) [20 How do you know those neutrinos came from the Sun? What changed when solar neutrinos became individual, timed events?](https://sandboxphysics.com/stories/neutrinos/kamiokande-real-time-solar-neutrinos/) [21 SNO: where did the Sun’s missing neutrinos go? Was something wrong with our picture of the Sun, or with what we expected neutrinos to do?](https://sandboxphysics.com/stories/neutrinos/sno-flavor-transformation/) [22 Why does passing through the Sun change a neutrino’s flavor? How can matter change a particle that usually passes straight through it?](https://sandboxphysics.com/stories/neutrinos/solar-matter-msw-effect/) [23 Borexino: how do you hear the Sun inside a radioactive world? What has to become quiet before low-energy solar neutrinos become visible?](https://sandboxphysics.com/stories/neutrinos/borexino-low-background-solar-neutrinos/) [24 After the missing neutrinos were explained, what could they tell us about the Sun? Can a neutrino measurement tell us what the solar core is made of?](https://sandboxphysics.com/stories/neutrinos/solar-neutrinos-and-solar-models/) ### Understand flavor change and mass [25 Before anyone saw oscillations, how did the mixing idea take shape? Why does the modern mixing matrix carry four names?](https://sandboxphysics.com/stories/neutrinos/pontecorvo-maki-nakagawa-sakata-mixing/) [26 Why can a neutrino change flavor? What changes during the journey if a neutrino does not need to collide with anything?](https://sandboxphysics.com/stories/neutrinos/neutrino-flavor-oscillations/) [27 How does the atmosphere make neutrinos all around us? Why do atmospheric neutrinos offer both a useful flavor comparison and many travel distances?](https://sandboxphysics.com/stories/neutrinos/atmospheric-neutrino-production/) [28 Super-Kamiokande: the neutrinos that took the long way Why did the detector see fewer muon neutrinos coming from below?](https://sandboxphysics.com/stories/neutrinos/super-k-zenith-angle/) [29 Is finding a missing flavor the same as finding a new one? What extra evidence do we gain by looking for the flavor that arrives?](https://sandboxphysics.com/stories/neutrinos/neutrino-appearance-and-disappearance/) [30 2015: how did two very different experiments establish flavor change? Why were the atmospheric and solar results stronger together?](https://sandboxphysics.com/stories/neutrinos/nobel-2015-two-neutrino-evidence-paths/) [31 Neutrinos have mass. Why does oscillation not tell us how much? How can an experiment establish that masses differ without weighing each state?](https://sandboxphysics.com/stories/neutrinos/oscillations-and-mass/) [32 Can the Earth help tell which neutrino mass comes first? Why does a journey through rock contain information about mass ordering?](https://sandboxphysics.com/stories/neutrinos/earth-matter-neutrino-mass-ordering/) ### Read reactors and the Earth [33 Where does a reactor’s antineutrino spectrum come from? Why can an accurately measured reactor power still leave an uncertain neutrino spectrum?](https://sandboxphysics.com/stories/neutrinos/reactor-antineutrino-spectrum-origins/) [34 KamLAND: testing a solar mystery with reactors on Earth Why were reactor antineutrinos arriving from roughly 180 kilometres away useful for understanding solar neutrinos?](https://sandboxphysics.com/stories/neutrinos/kamland-reactor-oscillations/) [35 Daya Bay: why compare a near detector with a far one? How can comparing detectors reduce uncertainty without making it disappear?](https://sandboxphysics.com/stories/neutrinos/daya-bay-near-far/) [36 RENO and Double Chooz: why repeat the mixing-angle measurement? What makes an independent measurement more than another number on the same plot?](https://sandboxphysics.com/stories/neutrinos/reno-double-chooz-independent-mixing-tests/) [37 JUNO: why must a huge detector resolve tiny spectral features? How can the spacing of spectral features say something that a total count cannot?](https://sandboxphysics.com/stories/neutrinos/juno-fine-spectrum-and-mass-ordering/) [38 The reactor anomaly and the spectrum bump ask different questions How can a measured spectrum contain both a deficit and an excess?](https://sandboxphysics.com/stories/neutrinos/reactor-anomaly-and-spectrum-bump/) [39 Short reactor baselines: look for a change with distance How do you test the sterile explanation without trusting one absolute flux prediction?](https://sandboxphysics.com/stories/neutrinos/short-baseline-reactor-sterile-tests/) [40 Geoneutrinos: what can particles tell us about the Earth’s heat? Why is detecting the Earth’s antineutrinos easier than uniquely measuring its mantle heat?](https://sandboxphysics.com/stories/neutrinos/geoneutrinos-earth-radiogenic-heat/) ### Make a source and test its journey [41 How do you make a beam of particles you cannot steer? If neutrinos have no electric charge, what are the beamline magnets focusing?](https://sandboxphysics.com/stories/neutrinos/making-an-accelerator-neutrino-beam/) [42 K2K and MINOS: test flavor change with a distance you choose What does a manufactured source add to evidence already found in the atmosphere?](https://sandboxphysics.com/stories/neutrinos/k2k-minos-controlled-baselines/) [43 T2K: why look slightly away from the beam axis? How can a small angular offset make a long-baseline measurement more informative?](https://sandboxphysics.com/stories/neutrinos/t2k-off-axis-beam-and-appearance/) [44 NOvA: how appearance, disappearance and the Earth fit together Why can more electron-flavor events have more than one explanation?](https://sandboxphysics.com/stories/neutrinos/nova-appearance-disappearance-and-matter/) [45 OPERA: tau appearance and a corrected clock anomaly How can a valid appearance discovery coexist with a rejected timing claim?](https://sandboxphysics.com/stories/neutrinos/opera-tau-appearance-and-timing-correction/) [46 DUNE: what detailed argon images and a long baseline can answer Why does a sharper interaction image still need a near detector and an uncertainty model?](https://sandboxphysics.com/stories/neutrinos/dune-liquid-argon-and-long-baseline/) [47 Hyper-K: a larger target still needs a precise comparison What does a much larger water detector improve, and what must still be calibrated?](https://sandboxphysics.com/stories/neutrinos/hyper-kamiokande-mass-and-systematics/) [48 Neutrino CP violation: what comparing neutrinos with antineutrinos can show When do different neutrino and antineutrino samples imply a symmetry is broken?](https://sandboxphysics.com/stories/neutrinos/neutrino-cp-violation-measurement/) ### Weigh the particle and test its nature [49 KATRIN: limiting neutrino mass at the end of the beta spectrum How can electrons constrain the mass of an unobserved neutrino?](https://sandboxphysics.com/stories/neutrinos/katrin-beta-endpoint-neutrino-mass/) [50 Dirac or Majorana: is the neutrino its own antiparticle? Which observation could distinguish two theories that ordinary oscillations leave open?](https://sandboxphysics.com/stories/neutrinos/dirac-majorana-neutrino-nature/) [51 Double-beta searches: why use several nuclei? What does a longer half-life limit tell us across different instruments?](https://sandboxphysics.com/stories/neutrinos/global-neutrinoless-double-beta-searches/) [52 Weigh neutrinos with the universe: what is assumed? Why can two cosmological analyses return different mass limits?](https://sandboxphysics.com/stories/neutrinos/cosmology-neutrino-mass-inference/) [53 Sterile neutrinos: an explanation must pass several tests Why does an unexplained excess not establish a new neutrino?](https://sandboxphysics.com/stories/neutrinos/sterile-neutrinos-anomalies-and-tests/) [54 Neutrinos in 2026: which questions remain open? How can you read a research frontier without mistaking a preference for a discovery?](https://sandboxphysics.com/stories/neutrinos/open-neutrino-questions-2026/) ### Follow the measurement chain [55 Coherent nuclear scattering: a small detector, a tiny recoil How can a more likely interaction leave a signal that is harder to measure?](https://sandboxphysics.com/stories/neutrinos/coherent-neutrino-nucleus-scattering/) [56 Neutrino energy: the nucleus is part of the measurement Why is the energy of an incoming neutrino not simply the energy we see?](https://sandboxphysics.com/stories/neutrinos/neutrino-cross-sections-energy-reconstruction/) [57 Why put a neutrino experiment under rock, sea or ice? What does a remote site remove, and which backgrounds remain?](https://sandboxphysics.com/stories/neutrinos/underground-underwater-neutrino-sites/) [58 Water, scintillator and argon: what does each detector see? Does a brighter event always contain more information about the neutrino?](https://sandboxphysics.com/stories/neutrinos/neutrino-detector-measurement-chains/) ### Build a new way to observe the sky [59 SN 1987A: a supernova seen from underground What could a few signals in underground tanks tell us about a distant star?](https://sandboxphysics.com/stories/neutrinos/sn1987a-burst/) [60 Before IceCube: learning to build telescopes in water and ice What had to work before a vast volume of water or ice could become a telescope?](https://sandboxphysics.com/stories/neutrinos/before-icecube-underwater-telescopes/) [61 IceCube: how do you turn a cubic kilometre of ice into an instrument? What has to work for a neutrino interaction to become trustworthy data?](https://sandboxphysics.com/stories/neutrinos/icecube-ice-sensors-and-calibration/) [62 IceCube’s 28 events: finding high-energy neutrinos from space How could researchers tell that the atmosphere was not the whole story?](https://sandboxphysics.com/stories/neutrinos/icecube-2013-evidence/) [63 TXS 0506+056: one alert, two separate lines of evidence How can a single event and an excess in older data both support a link to one source while remaining separate results?](https://sandboxphysics.com/stories/neutrinos/txs-0506-056-multimessenger/) [64 NGC 1068: what does a neutrino excess establish? How do many uncertain directions become evidence for one galaxy?](https://sandboxphysics.com/stories/neutrinos/ngc-1068-neutrino-source-evidence/) [65 Sea, lake and ice: telescopes with complementary skies Why is another neutrino telescope more than extra volume?](https://sandboxphysics.com/stories/neutrinos/neutrino-telescopes-complementary-sky/) [66 One neutrino sky, three different questions Does detecting cosmic neutrinos mean we have already mapped their individual sources?](https://sandboxphysics.com/stories/neutrinos/neutrino-sky-diffuse-galactic-point-sources/) ### Read evidence, data and worldwide contributions [67 Read the world through neutrino experiments What should a dot on an experiment map tell us?](https://sandboxphysics.com/stories/neutrinos/global-neutrino-experiment-geography/) [68 The engineering inside a neutrino measurement Which parts of a discovery happen before a physics fit?](https://sandboxphysics.com/stories/neutrinos/neutrino-calibration-engineering-software/) [69 When can a few neutrino events become evidence? Does seeing five events mean the same thing in every experiment?](https://sandboxphysics.com/stories/neutrinos/few-neutrino-events-statistical-evidence/) [70 Open a real neutrino event file and read it carefully What can a public event table establish on its own?](https://sandboxphysics.com/stories/neutrinos/reading-public-neutrino-event-data/) [71 How an international experiment keeps its knowledge How does knowledge survive after the original builders leave?](https://sandboxphysics.com/stories/neutrinos/international-neutrino-collaboration-knowledge/) [72 1930–2026: a timeline of neutrino evidence What changed at each historical milestone?](https://sandboxphysics.com/stories/neutrinos/neutrino-evidence-timeline-1930-2026/) Change a condition ## Build the evidence yourself 15 teaching models. Each Lab generates its own data, and none of it is original collaboration data. [ACCELERATOR · CP PHASE Same journey, different odds Record spectra from a neutrino beam and an antineutrino beam, then pull apart the effects of the CP phase, matter and detector assumptions. Open Lab](https://sandboxphysics.com/labs/long-baseline-cp/) [NEUTRINO ASTRONOMY · SKY SEARCH A hotspot, or a lucky sky? Look for a hotspot among recorded neutrino directions. Paired background skies show what each extra candidate costs. Open Lab](https://sandboxphysics.com/labs/neutrino-sky-search/) [BETA DECAY · ORIGINS One electron, a whole spectrum Replay a decay and compare a continuum with a two-body line. Open Lab](https://sandboxphysics.com/labs/beta-energy-sharing/) [RARE DECAY · NATURE Two electrons, one forbidden peak Open a cryogenic detector array and run a rare-decay search on one recorded set of counts. Open Lab](https://sandboxphysics.com/labs/neutrinoless-double-beta/) [ENDPOINT · MASS A giant filter for a tiny missing energy Scan the end of the beta spectrum, then see how calibration changes the fit to the same counts. Open Lab](https://sandboxphysics.com/labs/beta-endpoint-mass/) [REACTOR · SPECTRA Two distances, one subtle dip Fit spectra from a near and a far detector, then refit the same counts with a different energy calibration. Open Lab](https://sandboxphysics.com/labs/reactor-near-far-spectra/) [MATTER · RESONANCE Matter turns the quantum compass Send a neutrino through slow and sudden changes in density, and follow its coherent state numerically. Open Lab](https://sandboxphysics.com/labs/neutrino-matter-resonance/) [SUPERNOVA · TIMING A star speaks before it shines Record a burst, test a trigger on it, and follow one flash of light through a spherical detector. Open Lab](https://sandboxphysics.com/labs/supernova-neutrino-burst/) [ARGON · IONIZATION A clock becomes a dimension Drift the electrons from one ionization deposit onto three wire planes, then recover the center of charge in each time slice. Open Lab](https://sandboxphysics.com/labs/liquid-argon-tpc/) [SUN · HEAVY WATER Recover the missing flavor Replay a heavy-water detector. Its three reactions respond differently to each flavor; find where their flux limits cross for one recorded exposure. Open Lab](https://sandboxphysics.com/labs/solar-neutrino-flux/) [ATMOSPHERE · DIRECTION Use Earth as a baseline Compare upward and downward event counts in each energy band, with the source model and detector acceptance stated. Open Lab](https://sandboxphysics.com/labs/atmospheric-neutrino-zenith/) [REACTOR · TIME Find a pair in the noise Record detector pulses, change the coincidence window and check the background against a time-shifted copy of the data. Open Lab](https://sandboxphysics.com/labs/reactor-coincidence/) [WATER · GEOMETRY Make a ring from light Change a charged particle’s speed and direction, and trace its photons onto a flat detector plane. Open Lab](https://sandboxphysics.com/labs/cherenkov-rings/) [ICE · INFERENCE Reconstruct an unseen track Generate sensor times and charges, hide the true track, then fit its direction from the data. Open Lab](https://sandboxphysics.com/labs/icecube-reconstruction/) [VACUUM · MIXING Follow a changing flavor Scan the distance traveled in vacuum, watch the mass-state phases, then compare the probabilities with counts from ideal measurements. Open Lab](https://sandboxphysics.com/labs/neutrino-flavor-propagation/) Different places, connected questions ## The world behind the discovery Selected milestones to start reading from, not a complete history. The country that hosts an experiment does not tell you everyone who contributed. 1. 1930 ### [Wolfgang Pauli](https://sandboxphysics.com/stories/neutrinos/pauli-neutrino-letter/) A neutral particle is proposed 2. 1933–34 ### [Enrico Fermi](https://sandboxphysics.com/stories/neutrinos/fermi-beta-decay-theory/) A calculable theory of beta decay 3. 1956 ### [Savannah River](https://sandboxphysics.com/stories/neutrinos/reactor-first-detection/) Reactor antineutrinos detected directly 4. 1957–62 ### [Pontecorvo · Maki · Nakagawa · Sakata](https://sandboxphysics.com/stories/neutrinos/pontecorvo-maki-nakagawa-sakata-mixing/) Different routes towards neutrino mixing 5. 1962 ### [Brookhaven · Columbia](https://sandboxphysics.com/stories/neutrinos/brookhaven-muon-neutrino/) A beam shows that muon neutrinos are a separate flavor 6. 1968 ### [Homestake](https://sandboxphysics.com/stories/neutrinos/homestake-solar-neutrino-problem/) A persistent solar-neutrino shortfall 7. 1973 ### [Gargamelle · CERN](https://sandboxphysics.com/stories/neutrinos/gargamelle-neutral-currents/) Weak neutral currents survive background tests 8. 1978–85 ### [Wolfenstein · Mikheyev · Smirnov](https://sandboxphysics.com/stories/neutrinos/solar-matter-msw-effect/) Matter changes how flavor evolves 9. 1987 ### [Kamiokande-II · IMB · Baksan](https://sandboxphysics.com/stories/neutrinos/sn1987a-burst/) Three detectors catch one supernova burst 10. 1988–89 ### [Kamiokande-II](https://sandboxphysics.com/stories/neutrinos/kamiokande-real-time-solar-neutrinos/) Solar neutrinos gain a direction and an arrival time 11. 1989 ### [LEP · CERN](https://sandboxphysics.com/stories/neutrinos/lep-light-neutrinos/) Count light neutrinos through Z decay 12. 1990–92 ### [SAGE · GALLEX](https://sandboxphysics.com/stories/neutrinos/gallium-low-energy-solar-neutrinos/) Open a lower-energy solar window 13. 1998 ### [Super-Kamiokande](https://sandboxphysics.com/stories/neutrinos/super-k-zenith-angle/) Atmospheric flavor and travel distance 14. 1999–2006 ### [K2K · KEK → Kamioka](https://sandboxphysics.com/stories/neutrinos/k2k-minos-controlled-baselines/) A timed beam tests a chosen 250-kilometer journey 15. 2000–01 ### [DONUT · Fermilab](https://sandboxphysics.com/stories/neutrinos/donut-tau-neutrino/) Direct evidence for tau-neutrino interactions 16. 2002 ### [SNO](https://sandboxphysics.com/stories/neutrinos/sno-flavor-transformation/) Solar electron neutrinos and the total of all active flavors 17. 2002–03 ### [KamLAND](https://sandboxphysics.com/stories/neutrinos/kamland-reactor-oscillations/) Reactor antineutrinos test the solar explanation 18. 2005–22 ### [KamLAND · Borexino](https://sandboxphysics.com/stories/neutrinos/geoneutrinos-earth-radiogenic-heat/) Antineutrinos from Earth constrain its radioactive heat 19. 2006 ### [MINOS · Fermilab → Soudan](https://sandboxphysics.com/stories/neutrinos/k2k-minos-controlled-baselines/) Rate and spectrum test muon-flavor loss 20. 2011–20 ### [Double Chooz · RENO](https://sandboxphysics.com/stories/neutrinos/reno-double-chooz-independent-mixing-tests/) Independent sites cross-check reactor antineutrino disappearance 21. 2012 ### [Daya Bay](https://sandboxphysics.com/stories/neutrinos/daya-bay-near-far/) Near and far detectors reveal a small deficit 22. 2013 ### [IceCube](https://sandboxphysics.com/stories/neutrinos/icecube-2013-evidence/) Evidence for a high-energy cosmic population 23. 2014 ### [T2K · J-PARC → Kamioka](https://sandboxphysics.com/stories/neutrinos/t2k-off-axis-beam-and-appearance/) Electron-flavor appearance in an off-axis beam 24. 2015–18 ### [OPERA · CERN → Gran Sasso](https://sandboxphysics.com/stories/neutrinos/opera-tau-appearance-and-timing-correction/) Tau appearance identified from tracks in emulsion 25. 2015 ### [Nobel Prize · Kajita · McDonald](https://sandboxphysics.com/stories/neutrinos/nobel-2015-two-neutrino-evidence-paths/) Two independent paths to flavor change 26. 2017 ### [COHERENT · Oak Ridge](https://sandboxphysics.com/stories/neutrinos/coherent-neutrino-nucleus-scattering/) A pulsed source reveals coherent nuclear recoils 27. 2017–18 ### [TXS 0506+056 · IceCube · partner telescopes](https://sandboxphysics.com/stories/neutrinos/txs-0506-056-multimessenger/) An alert and an earlier neutrino excess 28. 2018–22 ### [Borexino · Gran Sasso](https://sandboxphysics.com/stories/neutrinos/borexino-low-background-solar-neutrinos/) Separate the Sun’s individual reactions at low energy 29. 2022 ### [NGC 1068 · IceCube](https://sandboxphysics.com/stories/neutrinos/ngc-1068-neutrino-source-evidence/) Testing a list of candidate sources finds an excess at an active galaxy 30. 2023 ### [Milky Way · IceCube](https://sandboxphysics.com/stories/neutrinos/neutrino-sky-diffuse-galactic-point-sources/) The Galactic plane adds a spread-out neutrino signal 31. 2025 ### [T2K · NOvA](https://sandboxphysics.com/stories/neutrinos/neutrino-cp-violation-measurement/) A joint fit whose CP limits depend on the mass ordering 32. 2025 ### [CONUS+ · Leibstadt](https://sandboxphysics.com/stories/neutrinos/coherent-neutrino-nucleus-scattering/) Reactor on/off data test tiny nuclear recoils 33. 2025 ### [DESI · Planck · ACT](https://sandboxphysics.com/stories/neutrinos/cosmology-neutrino-mass-inference/) Cosmological mass bounds depend on the model 34. 2025 ### [KATRIN · Karlsruhe](https://sandboxphysics.com/stories/neutrinos/katrin-beta-endpoint-neutrino-mass/) A beta-endpoint mass limit from 259 measurement days 35. 2025–26 ### [JUNO · Jiangmen](https://sandboxphysics.com/stories/neutrinos/juno-fine-spectrum-and-mass-ordering/) Fine reactor spectra measure oscillation parameters 36. 2026 ### [DUNE · Fermilab → Sanford](https://sandboxphysics.com/stories/neutrinos/dune-liquid-argon-and-long-baseline/) Far-detector construction and near-detector prototypes 37. 2026 ### [Hyper-K · Kamioka](https://sandboxphysics.com/stories/neutrinos/hyper-kamiokande-mass-and-systematics/) The tank lining is finished; observations are still to come 38. 2026 ### [KM3NeT · ARCA / ORCA](https://sandboxphysics.com/stories/neutrinos/neutrino-telescopes-complementary-sky/) Two complementary deep-sea detectors keep expanding 39. 2026 ### [IceTracks-DR2 · Public data](https://sandboxphysics.com/stories/neutrinos/reading-public-neutrino-event-data/) An updated track sample and detector response for source searches 40. 2026 ### [Nobel Prize · Francis Halzen](https://sandboxphysics.com/stories/neutrinos/nobel-physics-2026/) Recognition of a new observing window The same terms in two languages ## A small vocabulary for a large story - **Neutrino · 中微子**: An electrically neutral lepton detected through weak interactions. - **Antineutrino · 反中微子**: The antiparticle partner; different charged-current reactions distinguish it. - **Flavor · 味道**: Electron, muon or tau character defined by the associated charged lepton in a weak interaction. - **Mass state · 质量态**: A propagation state with a definite mass; a flavor state is a mixture of mass states. - **Oscillation · 振荡**: A change in flavor probabilities caused by relative quantum phases during propagation. - **Flux · 通量**: The particle flow per area and time, before detector response is applied. - **Cross section · 截面**: A measure of interaction probability, depending on the particle, energy and target. - **Baseline · 基线**: The distance from source to detector, with geometry specified for the experiment. - **Charged current / CC · 带电流 / CC**: A weak interaction mediated by a charged W boson, relating a neutrino to a charged lepton. - **Neutral current / NC · 中性流 / NC**: A weak interaction mediated by the neutral Z boson; active neutrino flavor is not tagged by an outgoing charged lepton. - **Background · 本底**: Other processes that can enter the selected sample; estimated or constrained separately. - **Exposure · 曝光**: The source or target and useful observation time relevant to a specified measurement. - **Reconstructed direction · 重建方向**: An estimate inferred from detector signals, with finite resolution and assumptions. - **SNU · 太阳中微子单位**: A capture-rate unit per target isotope atom; it is not an event count. Its exact definition is given in the radiochemical comparison. Definitions follow the PDG review and the source-linked articles in this collection. [PDG ↗](https://pdg.lbl.gov/2024/reviews/rpp2024-rev-neutrino-mixing.pdf) Published 9 October 2026 · Updated 15 October 2026 · Independent educational feature by Sandbox Physics. Each article lists its sources, what it covers and when it was last revised. More historical and experimental questions will be added over time.