English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

The static electromagnetic properties of the $W$ boson, $\Delta \kappa$ and$\Delta Q$, are calculated in the T-parity and non T-parity littlest Higgsmodel (LHM) including terms up to the order of $(v/f)^4$, with $v$ the standardmodel (SM) vacuum expectation value and $f$ the scale of the global symmetrybreaking. There are contributions from the virtual effects of the new heavyparticles and also from the new corrections to the SM vertices, which depend onthe mixing parameter $c$ and decrease quickly as $f$ increases. Depending onthe value of $c$, the partial contributions to $\Delta \kappa$ and $\Delta Q$can add constructively or destructively. The terms of the order of $(v/f)^4$are subdominant but they can add constructively and can enhance the $W$ formfactors for $f < 1$ TeV. In general the size of the $W$ form factors is verysuppressed in the LHM without T-parity as the constraints on the scale $f$ fromelectroweak precision measurements are very tight. The LHM with T-parity has nosuch constraints and it allows for values of $W$ form factors similar to thosefound in other weakly coupled SM extensions, though they are out of theexpected sensitivity of future measurements at the LHC. We also discuss thepossibility that there is some enhancement due to the interactions arising fromthe strongly interacting ultraviolet completion of the LHM.

On-shell $WW\gamma$ vertex in the T-Parity and non T-Parity Littlest Higgs model