Speaker
Description
Summary
The current data on the Higgs coupling shows a strong degeneracy in the best fit solutions for the Higgs couplings in the $(c_t, c_g)$ space. We propose to use the $p p\to h+j$ process to resolve this degeneracy. Indeed the Higgs interaction with gluons generated by the loops of the Standard Model top quark and the dimension five operator have different $p_T$ dependence and this can be used to measure the effective Higgs couplings to tops and gluons.
To estimate the LHC potential we have looked at the 4 lepton final state. Due to the very small rate of the signal this measurement can become possible only with very high luminosity at the LHC. The expected constraints on $c_t$ look, so far, inferior compared to the prospects in the direct measurements of the $t\bar{t}h$ coupling (ATLAS projections for the $3000$ fb$^{-1}$ predict the determination of the top Yukawa coupling with a $\sim 10\%$ accuracy). However $h+j$ can be used to reduce errors on the $c_g$ coupling when combined with the $c_t$ measurements from $t\bar{t}h$ production. Exploring other Higgs decay final states can also largely increase the precision of the $(c_t,c_g)$ measurements.
We also propose an observables with reduced theoretical errors, $r_\pm$, which can be used as alternative discriminant of new physics signal. We show that theoretical and experimental errors can be disentangled in $r_\pm$.
Probing Higgs couplings with high $p_T$ Higgs production, JHEP01 (2014) 014
