Recent advances in b, c, and s quark tagging coupled with novel statistical analysis techniques will allow future high energy and high statistics electron-positron colliders, such as the FCC-ee, to place phenomenologically relevant bounds on flavor violating Higgs and Z decays to quarks. We assess the FCC-ee reach for Z/h→bs,cu decays as a function of jet tagging performance. We also update the SM predictions for the corresponding branching ratios, as well as the indirect constraints on the flavor violating Higgs and Z couplings to quarks. Using type III two Higgs doublet model as an example of beyond the standard model physics, we show that the searches for h→bs,cu decays at FCC-ee can probe new parameter space not excluded by indirect searches. We also reinterpret the FCC-ee reach for Z→bs,cu in terms of the constraints on models with vectorlike quarks.
@article{arxiv.2306.17520,
title = {Flavor violating Higgs and $Z$ decays at FCC-ee},
author = {Jernej F. Kamenik and Arman Korajac and Manuel Szewc and Michele Tammaro and Jure Zupan},
journal= {arXiv preprint arXiv:2306.17520},
year = {2024}
}