Tau neutrino
The tau neutrino or tauon neutrino is an elementary particle which has the symbol
ν
τ and zero electric charge. Together with the tau (τ), it forms the third generation of leptons, hence the name tau neutrino. Its existence was immediately implied after the tau particle was detected in a series of experiments between 1974 and 1977 by Martin Lewis Perl with his colleagues at the SLAC–LBL group.[1] The discovery of the tau neutrino was announced in July 2000 by the DONUT collaboration (Direct Observation of the Nu Tau).[2][3] In 2024, the IceCube Neutrino Observatory published findings of seven astrophysical tau neutrino candidates.[4][5]
| Composition | Elementary particle |
|---|---|
| Statistics | Fermionic |
| Family | Lepton |
| Generation | Third |
| Interactions | Weak, gravity |
| Symbol | ν τ |
| Antiparticle | Tau antineutrino ( ν τ) |
| Theorized | Mid 1970s |
| Discovered | DONUT collaboration (2000) |
| Mass | Nonzero (See Neutrino mass) |
| Electric charge | 0 e |
| Color charge | No |
| Spin | 1/2 |
| Weak isospin | 1/2 |
| Weak hypercharge | −1 |
| Chirality | left-handed (for right-handed neutrinos, see sterile neutrino) |
Discovery edit
The DONUT experiment from Fermilab was built during the 1990s to specifically detect the tau neutrino. These efforts came to fruition in July 2000, when the DONUT collaboration reported its detection.[2][3] The tau neutrino is last of the leptons, and is the second most recent discovered particle of the Standard Model (i.e., it was observed 12 years before the discovery of the Higgs boson in 2012).
See also edit
References edit
- ^ Perl, M.L.; et al. (1975). "Evidence for anomalous lepton production in
e+
e−
annihilation". Physical Review Letters. 35 (22): 1489. Bibcode:1975PhRvL..35.1489P. doi:10.1103/PhysRevLett.35.1489. - ^ a b Jackson, Judy; et al. (20 July 2000). "Physicists find first direct evidence for tau neutrino at Fermilab" (Press release). Batavia, IL: Fermilab.
- ^ a b Kodama, K.; et al. (DONUT collaboration) (2001). "Observation of tau neutrino interactions". Physics Letters B. 504 (3): 218–224. arXiv:hep-ex/0012035. Bibcode:2001PhLB..504..218D. doi:10.1016/S0370-2693(01)00307-0. S2CID 119335798.
- ^ Lea, Robert (March 14, 2024), "Scientists may have just caught 7 exotic "ghost particles" as they pierced through Earth", Space.com, retrieved 16 March 2024
- ^ Pennsylvania State University (March 13, 2024), "IceCube identifies seven astrophysical tau neutrino candidates", phys.org, retrieved 16 March 2024