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arXiv · 1909.12772

Top polarisation as a probe of CP-mixing top-Higgs coupling in $tjh$ signals

Riley Patrick·Andre Scaffidi·Pankaj Sharma
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Abstract

In this letter we explore beyond the Standard Model top-Higgs Yukawa couplings as a function of a CP-mixing parameter $\xi_t$ at the 14 TeV HL-LHC in the process $pp\to thj$. We observe that angular variables of the decay products of the top are non-trivially sensitive to $\xi_t$. This fact is exploited in a full detector level analysis that employs machine learning techniques to optimize signal sensitivity on a suite of variables, including lepton azimuthal angle. The key result of this study is an improved projected exclusion limit on $\xi_t$ even when including the realistic effects of detector smearing and a conservative estimate of systematic error.

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Riley Patrick, Andre Scaffidi, Pankaj Sharma. 2019-09-27. Top polarisation as a probe of CP-mixing top-Higgs coupling in $tjh$ signals. https://doi.org/10.1103/physrevd.101.093005

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