Exploring anomalous $hb\bar b$ and $h b\bar b\gamma$ couplings in the context of the LHC and an $e^+e^-$ collider

Abstract

In the light of the 125 GeV Higgs ($h$) discovery at the Large Hadron Collider (LHC), one of the primary goals of the LHC and possible future colliders is to understand its interactions more precisely. Here we have studied the $h$-$b$-$\bar b$-$\gamma$ effective interaction terms arising out of gauge invariant dimension six operators in a model independent setting, as a potential source of new physics. Their role in some detectable final states have been compared with those coming from anomalous $h$-$b$-$\bar b$ interactions. We have considered the bounds coming from the existing collider and other low energy experimental data in order to derive constraints on the potential new physics couplings and predict possible collider signals for the two different new physics scenarios in the context of 14 TeV LHC and and a future $e^+e^-$ machine. We conclude that the anomalous $h$-$b$-$\bar b$-$\gamma$ coupling can be probed at the LHC at 14 TeV at the 3$\sigma$ level with an integrated luminosity of $\sim 2000~{\rm fb}^{-1}$, which an $e^+e^-$ collider can probe at the 3$\sigma$ level with $\sim 12(7)~{\rm fb}^{-1}$ at $\sqrt{s}=250(500)~{\rm GeV}$. It is also found that anomalous $h$-$b$-$\bar b$ interactions, subject to the existing LHC constraints, can not compete with the rates driven by $h$-$b$-$\bar b$-$\gamma$ effective interactions.