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

We use a recent formalism of the weak hadronic reactions $\tau^- \to\nu_{\tau} M_1 M_2$ to study the helicity amplitudes in $\tau^- \to \nu_{\tau}V P$ decay. This recent formalism maps the transition matrix elements at thequark level into hadronic matrix elements, and finally writes the weak matrixelements in terms of easy analytical formulas evaluated by means of anelaborate angular momentum algebra. The formalism provides directly theamplitudes for the different spin third components of the vector mesonsinvolved. We extend the formalism to a general case, with the operator$\gamma^\mu -\alpha\gamma^\mu \gamma_5$, that can account for different modelsbeyond the standard model and study in detail the $\tau^- \to \nu_{\tau} K^{*0}K^{-} $ reaction for the different helicities of the $K^{*0}$. The results areshown in terms of the $\alpha$ parameter that differs for each model. We findthat $\frac{d \Gamma}{d M_{\rm inv}^{(K^{*0} K^{-} )}}$ is very different forthe different components $M=\pm 1, 0$ and in particular the magnitude $\frac{d\Gamma}{d M_{\rm inv}^{(K^{*0} K^{-} )}}|_{M=+1} -\frac{d \Gamma}{d M_{\rminv}^{(K^{*0} K^{-} )}}|_{M=-1} $ is very sensitive to the $\alpha$ parameter,which makes the investigation of this magnitude a most welcome initiative totest different models beyond the standard model.

Polarization amplitudes in $\tau^- \to \nu_{\tau} V P$ decay beyond the standard model