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

Flavour-changing-neutral currents (FCNCs) involving the top quark are highlysuppressed within the Standard Model (SM). Hence, any signal in current orplanned future collider experiments would constitute a clear manifestation ofphysics beyond the SM. We propose a novel, interference-based strategy tosearch for top-quark FCNCs involving the $Z$ boson that has the potential tocomplement traditional search strategies due to a more favourable luminosityscaling. The strategy leverages on-shell interference between the FCNC and SMdecay of the top quark into hadronic final states. We estimate the feasibilityof the most promising case of anomalous $tZc$ couplings using Monte Carlosimulations and a simplified detector simulation. We consider the mainbackground processes and discriminate the signal from the background with adeep neural network that is parametrised in the value of the anomalous $tZc$coupling. We present sensitivity projections for the HL-LHC and the FCC-hh. Wefind an expected $95\%$ CL upper limit of$\mathcal{B}_{\mathrm{excl}}(t\rightarrow Zc) = 6.4 \times 10^{-5}$ for theHL-LHC. In general, we conclude that the interference-based approach has thepotential to provide both competitive and complementary constraints totraditional multi-lepton searches and other strategies that have been proposedto search for $tZc$ FCNCs.

Leveraging on-shell interference to search for FCNCs of the top quark and the Z boson