Neutralino
From Wikipedia, the free encyclopedia
In particle physics, the neutralino is a hypothetical particle and part of the doubling of the menagerie of particles predicted by supersymmetric theories.
Since the superpartners of the Z boson (zino), the photon (photino) and the neutral higgs (higgsino) have the same quantum numbers, they mix to form eigenstates of the mass operator, called neutralinos. The lightest neutralino is thought to be stable unless the gravitino is lighter or R-parity is not conserved. Virtually undetectable, it participates only in weak and gravitational interactions. If the neutralino is stable, it will always escape a particle detector. Therefore its production inside the detector, through a known initial state (e.g. proton-proton collision), should be accompanied with large missing energy and momentum from the visible final state particles. This is important signature to discriminate it from Standard Model backgrounds.
Of the weakly interacting massive particles (WIMPs) under consideration, a lightest neutralino of 30-5000 GeV is the leading candidate for cold dark matter. The exact behavior of this particle will depend on the dominant constituent: the higgsino, the photino or the zino.
The standard symbol for neutralinos in 
, where i runs from 1 to 4.
[edit] See also
|
|
|
| Fermions: Quarks: (Up · Down · Strange · Charm · Bottom · Top) | Leptons: (Electron · Muon · Tau · Neutrinos) | |
| Gauge bosons: Photon | W and Z bosons | Gluons | |
| Not yet observed: Higgs boson | Graviton | Other hypothetical particles | |
 |
This particle physics-related article is a stub. You can help Wikipedia by expanding it. |
