Search for single vector-like B quark production and decay via B → bH($$ b\overline{b} $$) in pp collisions at $$ \sqrt{s} $$ = 13 TeV with the ATLAS detector
A bstract A search is presented for single production of a vector-like B quark decaying into a Standard Model b -quark and a Standard Model Higgs boson, which decays into a $$ b\overline{b} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mi>b</mml:mi> <mml:mover> <mml:mi>b</mml:mi> <mml:mo>¯</mml:mo> </mml:mover> </mml:math> pair. The search is carried out in 139 fb − 1 of $$ \sqrt{s} $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msqrt> <mml:mi>s</mml:mi> </mml:msqrt> </mml:math> = 13 TeV proton-proton collision data collected by the ATLAS detector at the LHC between 2015 and 2018. No significant deviation from the Standard Model background prediction is observed, and mass-dependent exclusion limits at the 95% confidence level are set on the resonance production cross-section in several theoretical scenarios determined by the couplings c W , c Z and c H between the B quark and the Standard Model W , Z and Higgs bosons, respectively. For a vector-like B occurring as an isospin singlet, the search excludes values of c W greater than 0.45 for a B resonance mass ( m B ) between 1.0 and 1.2 TeV. For 1 . 2 TeV < m B < 2 . 0 TeV, c W values larger than 0.50–0.65 are excluded. If the B occurs as part of a ( B, Y ) doublet, the smallest excluded c Z coupling values range between 0.3 and 0.5 across the investigated resonance mass range 1 . 0 TeV < m B < 2 . 0 TeV.
Tópico:
Particle physics theoretical and experimental studies
