Search for single vector-like $B$ quark production in hadronic final states at the LHC

Abstract

In this paper, we study the discovery potential of a Vector-Like $B$ quark (VLB) via the process $pp\to B(\to bZ)j\to b(Z\to {\nu }_l\overline{{\nu }_l})j$ at the Large Hadron Collider (LHC) with $\sqrt{s}=14$ TeV. In the framework of a simplified model, we perform a scan over its parameter space and test its viability following a Monte Carlo analysis developed to include all production and decay dynamics. We use cut-and-count combined with Extreme Gradient Boosting (XGBoost) methods to classify the signal and background events in order to improve the efficiency of signal identification and background rejection. We find that this approach can reduce background events significantly while the signal retention rate is much higher than that of traditional methods, thereby improving the VLB discovery potential. We then calculate the exclusion and discovery capabilities for VLBs and find that the advantages of the cut-and-count plus XGBoost method especially lie in the high-mass region, i.e., $m_B>1500\text{ GeV}$. We finally obtain the following LHC results in terms of the coupling and chiral structure of a singlet heavy VLB interactions: (i) for $g^{\ast }$=0.2 and $R_L=0$ with 3000 fb${}^{-1}$, the $B$ quark mass can be be excluded (discovered) up to 3000 GeV (2500 GeV); (ii) for $g^{\ast }$=0.2 and $R_L=0.5$ with 3000 fb${}^{-1}$, the exclusion (discovery) region can reach up to 4750 GeV (4250 GeV).

Published version; 26 pages, 7 figures, 5 tables

References in corpus (26)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• MadAnalysis 5, a user-friendly framework for collider phenomenology
• Bounds and Decays of New Heavy Vector-like Top Partners
• Early discovery of top partners and test of the Higgs nature
• Interpreting the $W$-mass anomaly in the vectorlike quark models
• Global Fit of Modified Quark Couplings to EW Gauge Bosons and Vector-Like Quarks in Light of the Cabibbo Angle Anomaly
• A search for bottom-type, vector-like quark pair production in a fully hadronic final state in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Fermion mass hierarchies from vector-like families with an extended 2HDM and a possible explanation for the electron and muon anomalous magnetic moments
• Roadmap to explore vectorlike quarks decaying to a new scalar or pseudoscalar
• A leptoquark and vector-like quark extended model for the simultaneous explanation of the $W$ boson mass and muon $g-2$ anomalies
• Search for single production of the heavy vectorlike $T$ quark with $T\to th$ and $h\to \gamma \gamma$ at the high-luminosity LHC
• Search for single production of a top quark partner via the $T\to th$ and $h\to W{W}^{\ast }$ channels at the LHC
• Discovery prospects of a vectorlike top partner decaying to a singlet boson
• Asymmetry in flavour changing electromagnetic transitions of vector-like quarks
• Machine learning-enhanced search for a vectorlike singlet $B$ quark decaying to a singlet scalar or pseudoscalar
• Heavy vector-like quarks decaying to exotic scalars: a case study with triplets
• Search for vector-like bottom quark via $Zb$ production at the LHC
• Single production of vector-like top partner decaying to $Wb$ in the leptonic channel at $ep$ colliders in the LHT model
• Single production of vectorlike $B$ quarks at the CLIC
• Search for single production of vectorlike $B$-quarks at the LHC
• Single production of vector-like $T$ quark at future high-energy linear $e^{+}{e}^{-}$ collider
• Beyond Cuts in Small Signal Scenarios -- Enhanced Sneutrino Detectability Using Machine Learning
• Probing a new decay of vector-like top partner mediated by heavy Majorana neutrino via single production
• $Z$ mediated Flavour Changing Neutral Currents with a Fourth Vector-Like Family
• Pair production of the singlet vector-like B quark at the CLIC
• Discovering the Origin of Yukawa Couplings at the LHC with a Singlet Higgs and Vector-like Quarks

Cited by in corpus (4)

• Search for charged Higgs bosons through vector-like top quark pair production at the LHC
• Impact of hidden heavy Higgs channels of VLB-Quarks below 1 TeV in 2HDM
• Searching for single production of vectorlike quarks decaying into Wb at a future muon-proton collider
• Tagging ultra-boosted jets at FCC-hh using machine learning techniques