Probing the Higgs–strange-quark coupling at $e^+e^-$ colliders using light-jet flavor tagging

We propose a method to probe the coupling of the Higgs to strange quarks by tagging strange jets at future lepton colliders. For this purpose we describe a jet-flavor observable, JF, that is correlated with the flavor of the quark associated with the hard part of the jet. Using this variable, we set up a strangeness tagger aimed at studying the decay h→ss¯. We determine the sensitivity of our method to the strange Yukawa coupling, and find it to be of the order of the standard-model expectation.