Strange quark as a probe for new physics in the Higgs sector

Abstract

This paper describes a novel algorithm for tagging jets originating from the hadronisation of strange quarks (strange-tagging) with the future International Large Detector (ILD) at the International Linear Collider (ILC). It also presents the first application of such a strange-tagger to a Higgs to strange ($h\to s\bar{s}$) analysis with the $P(e^{-},e^{+})=(-80\%,+30\%)$ polarisation scenario, corresponding to 900 fb${}^{-1}$ of the initial proposed 2000 fb${}^{-1}$ of data which will be collected by ILD during its first 10 years of data taking at $\sqrt{s}=250$ GeV. Upper limits on the Standard Model Higgs-strange coupling strength modifier, $\hat{I}{º}_s$, are derived at the 95% confidence level to be 7.14. The paper includes as well a preliminary study of a Ring Imaging Cherenkov (RICH) system capable of discriminating between kaons and pions at high momenta (up to 25 GeV), and thus enhancing strange-tagging performance at future Higgs factory detectors.

V1: 69 pages; V2: 80 pages, updated figures/numbers, additional appendices