相关论文: Bottom partner B' and Zb production at the LHC

We explore the "Beautiful Mirrors" model, which aims to explain the measured value of $A^b_{FB}$, discrepant at the $2.9\sigma$ level. This scenario introduces vector-like quarks which mix with the bottom, subtly affecting its coupling to…

We consider the Z polarization asymmetry A_Z=(sigma(Z_R)-sigma(Z_L))/(sigma(Z_R)+sigma(Z_L)) in the process of associated bZ production at the LHC. We show that in the Standard Model (SM) this quantity is essentially given by its Born…

The bottom quark forward-backward asymmetry ($A_{FB}^b$) data at LEP exhibits a long-standing discrepancy with the standard model prediction. We propose a novel method to probe the $Zb\bar{b}$ interactions through $gg\to Zh$ production at…

The $P_5'$ anomaly uncovered by the LHCb experiment in $B \to K^*\mu\mu$ angular observables has motivated a possible $Z'$ boson that couples to left-handed $b \to s$ transitions, where a model would be gauged $L_\mu - L_\tau$ symmetry, but…

In the framework of the Littlest Higgs Model with T-parity (LHT), we study the contributions of the new particles to $Zb\bar{b}$ couplings at one-loop level. Based on these results, we further study the branching ratio $R_{b}$ and the…

In light of the discovery of a Higgs-like particle at the LHC, we revisit the status of the precision electroweak data, focusing on two discrepant observables: 1) the long-standing 2.4 sigma deviation in the forward-backward asymmetry of…

We propose a new type of Z polarization asymmetry in bottom-Z production at LHC that should be realistically measurable and would provide the determination of the so-called $A_b$ parameter, whose available measured value still appears to be…

We investigate models of a heavy neutral gauge boson Z' which could explain anomalies in B meson decays reported by the LHCb experiment. In these models, the Z' boson couples mostly to third generation fermions. We show that bottom quarks…

We consider one of the most significant deviations from the Standard Model: the forward-backward asymmetry of the b-quark measured at leptonic colliders. We investigate the possibility to solve this discrepancy by introducing new physics at…

Recent $b\to s\ell\ell$ anomalies may imply the existence of a new $Z'$ boson with left-handed $Z'bs$ and $Z'\mu\mu$ couplings. Such a $Z'$ may be directly observed at LHC via $b \bar s \to Z' \to \mu^+\mu^-$, and its relevance to $b\to…

We propose a new strategy to probe the $Z$ boson couplings to bottom and charm quarks at the LHC. In this work we mainly focus on the case of bottom quarks. Here, the $Z$ boson is produced in association with two $b$-jets and decays to…

The production of B hadrons is among the most abundant fundamental QCD processes measured at the LHC. We present for the first time predictions for this process accurate to next-to-next-to-leading order in QCD perturbation theory by…

The left-right twin Higgs model (LRTHM) predicts the existence of the top partner $T$. In this work, we make a systematic investigation for the single and pair production of this top partner $T$ through the processes: $e^{+}e^{-}\to t\ov{T}…

We study single production and detection at the LHC run II of exotic partners of the bottom quark. For masses larger than 1 TeV single production can dominate over pair production that is suppressed due to phase space. The presence of…

We present a study of l\nu b\bar{b} and l+ l- b\bar{b} production at hadron colliders. Our results, accurate to the next-to-leading order in QCD, are based on automatic matrix-element calculations performed by MadLoop and MadFKS, and are…

Many new physics models predict the existence of extra neutral gauge bosons ($Z'$). Inspired by the recent development on Higgs search, we study the properties of $Z'$ via the Higgs and $Z$ boson associated production. The couplings of $Z'$…

The determination of the $Zb\bar{b}$ coupling in experiments has been a long-standing challenge, as the limited precision of off $Z$-pole measurements at the LEP has resulted in two degenerate solutions remained to be resolved. In this…

We study the sensitivity of top pair production at the Large Hadron Collider (LHC) to the nature of an underlying Z' boson, including full tree level standard model background effects and interferences. We demonstrate that exploiting…

In the context of the left-right twin Higgs (LRTH) model, we first examine the effects on the $Zt\bar t$ production at the ILC and LHC. Our results show that the cross-sections can be significantly deviated from the standard model…

We study the sensitivity of top pair production at the Large Hadron Collider (LHC) to the nature of an underlying Z' boson, including full tree level standard model background effects and interferences while assuming realistic final state…