Physics reach of $D_{(s)}\to \pi (K)\ell \ell$ and other charming null test opportunities

Abstract

We discuss possibilities to test physics beyond the Standard Model in $|\Delta c|=|\Delta u|=1$ semileptonic, hadronic and missing energy decay modes. Clean null test observables such as angular observables, CP-asymmetries and lepton universality tests are presented and model-independent correlations as well as details within flavorful, anomaly-free $Z^{\prime }$ models are worked out.

4 pages, 3 figures, contribution to the "2021 Electroweak session of the 55th Rencontres de Moriond"