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arXiv · 1503.00290

Constraining the Charm Yukawa and Higgs-quark Coupling Universality

Abstract

We introduce four different types of data-driven analyses with different level of robustness that constrain the size of the Higgs-charm Yukawa coupling: (i) recasting the vector-boson associated, Vh, analyses that search for bottom-pair final state. We use this mode to directly and model independently constrain the Higgs to charm coupling, y_c/y_c^{SM} < 234; (ii) the direct measurement of the total width, y_c/y_c^{SM} < 120-140; (iii) the search to h -> J/\psi\gamma, y_c/y_c^{SM} < 220; (iv) a global fit to the Higgs signal strengths, y_c/y_c^{SM} < 6.2. A comparison with t\bar{t}h data allows us to show that current data eliminates the possibility that the Higgs couples to quarks in a universal way, as is consistent with the Standard Model (SM) prediction. Finally, we demonstrate how the experimental collaborations can further improve our direct bound by roughly an order of magnitude by charm-tagging, as already used in new physics searches.

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Gilad Perez, Yotam Soreq, Emmanuel Stamou, Kohsaku Tobioka. 2015-03-01. Constraining the Charm Yukawa and Higgs-quark Coupling Universality. https://doi.org/10.1103/physrevd.92.033016

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