Salvato in:
| Autori principali: | , , |
|---|---|
| Natura: | Preprint |
| Pubblicazione: |
2023
|
| Soggetti: | |
| Accesso online: | https://arxiv.org/abs/2305.14050 |
| Tags: |
Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
|
| _version_ | 1866911947350343680 |
|---|---|
| author | Draukšas, Simonas Dūdėnas, Vytautas Lavoura, Luís |
| author_facet | Draukšas, Simonas Dūdėnas, Vytautas Lavoura, Luís |
| contents | The parametrization of the oblique corrections through $S$, $T$, and $U$ -- later extended by $V$, $W$, and $X$ -- is a convenient way of comparing the predictions for various electroweak observables at the one-loop level between the Standard Model and its extensions. That parametrization assumes that the extensions under consideration have ${SU(2)\times U(1)}$ gauge symmetry \emph{and} the tree-level relation $m_W = m_Z \cos{θ_W}$ between the Weinberg angle and the gauge-boson masses. In models where that relation does not hold at the Lagrangian level, the parameter $T$ is not ultraviolet-finite, making the parametrization inadequate. We present expressions that parametrize the difference of the various predictions of two models with $m_W \neq m_Z \cos{θ_W}$ in terms of oblique parameters. The parameter $T$ does not play a role in those expressions. Conveniently, they may be reached from the ones that were derived for models with tree-level $m_W = m_Z \cos{θ_W}$, by performing a simple substitution for $T$. We also discuss the difficulties in using oblique parameters when comparing a model with $m_W \neq m_Z \cos{θ_W}$ to the Standard Model. Finally, we compute the relevant five oblique parameters $S$, $U$, $V$, $W$, and $X$ in the SM extended by both, hypercharge $Y=0$ and $Y=1$, triplet scalars. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2305_14050 |
| institution | arXiv |
| publishDate | 2023 |
| record_format | arxiv |
| spellingShingle | Oblique corrections when $m_W \neq m_Z \cos{θ_W}$ at tree level Draukšas, Simonas Dūdėnas, Vytautas Lavoura, Luís High Energy Physics - Phenomenology The parametrization of the oblique corrections through $S$, $T$, and $U$ -- later extended by $V$, $W$, and $X$ -- is a convenient way of comparing the predictions for various electroweak observables at the one-loop level between the Standard Model and its extensions. That parametrization assumes that the extensions under consideration have ${SU(2)\times U(1)}$ gauge symmetry \emph{and} the tree-level relation $m_W = m_Z \cos{θ_W}$ between the Weinberg angle and the gauge-boson masses. In models where that relation does not hold at the Lagrangian level, the parameter $T$ is not ultraviolet-finite, making the parametrization inadequate. We present expressions that parametrize the difference of the various predictions of two models with $m_W \neq m_Z \cos{θ_W}$ in terms of oblique parameters. The parameter $T$ does not play a role in those expressions. Conveniently, they may be reached from the ones that were derived for models with tree-level $m_W = m_Z \cos{θ_W}$, by performing a simple substitution for $T$. We also discuss the difficulties in using oblique parameters when comparing a model with $m_W \neq m_Z \cos{θ_W}$ to the Standard Model. Finally, we compute the relevant five oblique parameters $S$, $U$, $V$, $W$, and $X$ in the SM extended by both, hypercharge $Y=0$ and $Y=1$, triplet scalars. |
| title | Oblique corrections when $m_W \neq m_Z \cos{θ_W}$ at tree level |
| topic | High Energy Physics - Phenomenology |
| url | https://arxiv.org/abs/2305.14050 |