Related papers: Pair production of heavy Q=2/3 singlets at LHC
We evaluate the LHC discovery potential for a light Higgs boson in t tbar H (-> l nu b bbar b bbar jj) production, within the Standard Model and if a new Q=2/3 quark singlet T with a moderate mass exists. In the latter case, T pair…
New quark singlets T can be produced in pairs at LHC through standard QCD interactions, with a large cross section for masses of several hundreds of GeV. Their charged current decays T Tbar T -> W+ b W- bbar, with semileptonic decay of the…
We systematically study the possible signals at LHC of new vector-like quarks mainly coupled to the third generation. We consider heavy quarks T, B, X, Y of charges 2/3, -1/3, 5/3 and -4/3, respectively, in SU(2)_L isosinglets T_{L,R},…
A search is presented for heavy-quark pair production (QQbar) under the decay hypothesis QQbar to WqWq with q = u,d,c,s,b. The search is performed with 1.04 fb^-1 of integrated luminosity from pp collisions at sqrt(s) = 7 TeV collected by…
We consider the phenomenology of the fourth generation heavy quarks which would be pair produced at the LHC. We show that if such a quark with a mass in the phenomenologically interesting range of 400 GeV--600 GeV decays to a light quark…
We present the prospects for the discovery or exclusion of heavy vector-like charge 2/3 quarks, T, in proton-proton collisions at two center-of-mass energies, 14 and 33 TeV at the LHC. In this note, the pair production of T quark and its…
A search is presented for pair production of a new heavy quark ($Q$) that decays into a $W$ boson and a light quark ($q$) in the final state where one $W$ boson decays leptonically (to an electron or muon plus a neutrino) and the other $W$…
The vectorlike top partners $T$ are predicted in many extensions of the Standard Model (SM). In a simplified model including a single vectorlike $T$ quark with charge $2/3$, we investigate the process $pp \to Tj$ induced by the couplings…
A search for the production of heavy partners of the top quark with charge 5/3 is performed in events with a pair of same-sign leptons. The data sample corresponds to an integrated luminosity of 19.5 inverse femtobarns and was collected at…
We consider an extension of the Standard Model involving a singlet Higgs and down type vector-like quarks in the light of the current LHC Higgs data. For a good range of the parameters of the Higgs potential, and a mass range for the heavy…
A sequential fourth generation of quarks and leptons is allowed by precision electroweak constraints if the mass splitting between the heavy quarks is between 50 and 80 GeV. Although heavy quarks can be easily detected at the LHC, it is…
A natural, non-supersymmetric solution to the hierarchy problem generically requires fermionic partners of the top quark with masses not much heavier than 500 GeV. We study the pair production and detection at the LHC of the top partners…
We present the results of a search for pair production of a heavy top-like (t') quark decaying to Wq final states using data corresponding to an integrated luminosity of 5.6 fb-1 collected by the CDF II detector in pp collisions at {\surd}s…
We examine the prospects for probing heavy top quark-antiquark (t-tbar) resonances at the upgraded LHC in pp collisions at $\root_s = 14 TeV. Heavy t-tbar resonances (Z' bosons) are predicted by several theories that go beyond the standard…
A search for pair production of massive vector-like T and B quarks in proton-proton collisions at sqrt(s) = 13 TeV is presented. The data set was collected in 2015 by the CMS experiment at the LHC and corresponds to an integrated luminosity…
New vectorlike quarks are predicted in many new physics scenarios beyond the Standard Model~(SM) and could potentially be discovered at the LHC. Based on a simplified model including a singlet vectorlike top partner with charge $2/3$, we…
A search is presented for production of a heavy up-type quark (t') together with its antiparticle, assuming a significant branching ratio for subsequent decay into a W boson and a b quark. The search is based on 4.7 fb^-1 of pp collisions…
We present the results of a search for a new heavy top-like quark, tprime, decaying to a W boson and another quark using the CDF II Detector in Run II of the Tevatron ppbar collider. New top-like quarks are predicted in a number of models…
We study the phenomenology at the Large Hadron Collider of an exotic vector-like quark X with charge +5/3. We relax the assumption of a 100% branching into W t and allow for an arbitrary rate into W plus light quarks, thus covering all…
Results are presented from a search for the pair-production of heavy quarks, Q Q-bar, that decay exclusively into a top quark and a W or Z boson. The search is performed using a sample of proton-proton collisions at sqrt(s) = 7 TeV…