Interactive tool
Mass ordering & flavour composition
Each neutrino mass eigenstate (ν₁, ν₂, ν₃) is a specific mixture of the three flavours, set by the PMNS matrix. Switch between the two possible mass orderings to see how the states are arranged — one of the field's open questions.
Flavour composition
- νe (electron)
- νμ (muon)
- ντ (tau)
| νe | νμ | ντ | |
|---|---|---|---|
| ν₁ | 68% | 8% | 24% |
| ν₂ | 30% | 38% | 31% |
| ν₃ | 2% | 53% | 44% |
The big gap is the atmospheric splitting, the small gap the solar splitting. The ordering — the sign of the atmospheric splitting — is not yet known; see Oscillations, Part 7. Composition from representative best-fit PMNS values.
About this tool
What it shows
The diagram illustrates the two possible orderings of the neutrino mass states — normal and inverted — and the flavour composition of each state from the PMNS matrix.
How to use it
Switch between the orderings and inspect how the electron, muon and tau content is distributed across the three mass states.
The physics
The mass ordering is one of the field’s biggest open questions. See normal vs inverted, why it matters, and the PMNS matrix.