Chargino

In elementary particle physics , Charginos are hypothetical , electrically charged ( English charge ) elementary particles that appear in supersymmetric theories. These are characterized by the fact that each (quantum) field is assigned a partner field that differs from the original by the amount  1/2 in the spin . Since the starting fields here are bosons ( integer spin), the Charginos themselves must be fermions ( half- integer spin). In particular, Charginos are Dirac fermions , that is, they differ from their antiparticles in terms of electrical charge.

Two charge pairs in the MSSM

In the minimal supersymmetric standard model (MSSM), Chargino's superposition states (mixtures, linear combinations ) are made up of superpartners of electrically charged calibration and Higgs fields . The former are the Gauginos and (Winos, partners of the fields W ¹ and W ² ), the latter are the charged Higgsinos (partners of the hypothetical charged Higgs bosons ). The result is the Chargino pairs 1 and 2, abbreviated with and (sometimes also and ). ${\displaystyle {\tilde {W}}^{1}}$ ${\displaystyle {\tilde {W}}^{2}}$ ${\displaystyle {\tilde {\chi }}_{1}^{\pm }}$ ${\displaystyle {\tilde {\chi }}_{2}^{\pm }}$ ${\displaystyle {\tilde {C}}_{1}^{\pm }}$ ${\displaystyle {\tilde {C}}_{2}^{\pm }}$

Alternative composition

The postulated Charginos can also be expressed as the superposition of the charged wino fields (instead of and ) with the charged Higgsinos. ${\displaystyle {\tilde {W}}^{\pm }}$ ${\displaystyle {\tilde {W}}^{1}}$ ${\displaystyle {\tilde {W}}^{2}}$

The charged wino fields are themselves linear combinations of and , in the same way as, according to the standard model, the electrically charged W bosons are mixtures of the fields W ¹ and W ² : ${\displaystyle {\tilde {W}}^{\pm }}$ ${\displaystyle {\tilde {W}}^{1}}$ ${\displaystyle {\tilde {W}}^{2}}$ ${\displaystyle W^{\pm }}$

${\displaystyle {\Psi _{W^{+}} \choose \Psi _{W^{-}}}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}1&i\\1&-i\end{pmatrix}}{\Psi _{W^{1}} \choose \Psi _{W^{2}}}}$

${\displaystyle \Rightarrow {\Psi _{{\tilde {W}}^{+}} \choose \Psi _{{\tilde {W}}^{-}}}={\frac {1}{\sqrt {2}}}{\begin{pmatrix}1&i\\1&-i\end{pmatrix}}{\Psi _{{\tilde {W}}^{1}} \choose \Psi _{{\tilde {W}}^{2}}}\,.}$
Therein is the wave function ${\displaystyle \Psi }$

Because the mixture with the charged Higgsinos, which has not yet been taken into account, the fields are - unlike W bosons - not yet candidates for particles that can be observed in principle. ${\displaystyle {\tilde {W}}^{\pm }}$ ${\displaystyle W^{\pm }}$

See also

• Neutralino : Mixtures of the uncharged Winos and Binos (partners of the electrically neutral Z bosons and photons ) and the uncharged Higgsinos