Related papers: Heavy Squarks at the LHC
Heavy vector-like quarks with electric charge $Q=2/3$ (also called \textit{heavy tops}) appear naturally in many extensions of the Standard Model. Although these typically predict the existence of further particles below the TeV scale,…
We report on a search for the pair production of second generation scalar leptoquarks (LQ) in ppbar collisions at the center of mass energy sqrt(s)=1.96 TeV using a data set corresponding to an integrated luminosity of 1.0 fb-1 collected…
A search for new heavy particles that decay into top-quark pairs is performed using data collected from proton-proton collisions at a centre-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The integrated…
We evaluate the potential of the CERN LHC collider to observe rare decays of the top quark in channels involving R-parity violating (RPV) interactions. We stress the importance of calculating top quark production and decay simultaneously as…
The results of a search for the production of second generation scalar leptoquarks are presented for final states consisting of either two oppositely charged muons and at least two jets or a muon plus missing transverse momentum and at…
We argue that evidence can be uncovered for stops between 300-600 GeV in 5 fb^-1 of 7 TeV proton-proton collisions if they decay into top quarks and light neutral particles. We also show that with 20 fb^-1 of 8 TeV running, discovery or…
We explore further the discovery potential for heavy quarks at the LHC, with emphasis on the $t'$ and $b'$ of a sequential fourth family associated with electroweak symmetry breaking. We consider QCD multijets, $t\bar{t}+\rm{jets}$,…
The results of a search for direct pair production of top squarks in events with two opposite-charge leptons (electrons or muons) are reported, using 36.1 fb$^{-1}$ of integrated luminosity from proton--proton collisions at $\sqrt{s}=13$…
The first 1/fb of LHC searches have set impressive limits on new colored particles decaying to missing energy. We address the implication of these searches for naturalness in supersymmetry (SUSY). General bottom-up considerations of natural…
A search for the production of a pair of top squarks at the LHC is presented. This search targets a region of parameter space where the kinematics of top squark pair production and top quark pair production are very similar, because of the…
We study the impact of machine-learning algorithms on LHC searches for leptoquarks in final states with hadronically decaying tau leptons, multiple $b$-jets, and large missing transverse momentum. Pair production of scalar leptoquarks with…
Measurements are made of differential cross-sections of highly boosted pair-produced top quarks as a function of top-quark and $t\bar{t}$ system kinematic observables using proton--proton collisions at a center-of-mass energy of $\sqrt{s} =…
The Large Hadron Collider (LHC) is the first machine that provides high enough energy to produce large numbers of boosted top quarks. The decay products of these top quarks are confined to a cone in the top quark flight direction and can be…
A search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from b quarks, and missing transverse momentum. The…
A search for pair-produced vector-like $T$-quarks in 139 fb$^{-1}$ of $pp$ collisions recorded by the ATLAS detector at a centre-of-mass energy $\sqrt{s}$=13 TeV is presented. The search targets signal events where at least one $T$-quark…
A search is presented for same-sign top-quark production and down-type heavy quarks of charge -1/3 in events with two isolated leptons (electrons or muons) that have the same electric charge, at least two jets and large missing transverse…
We examine the LHC discovery potential for new Q=2/3 quark singlets T in the process gg,qq -> T Tbar -> W+ b W- bbar, with one W boson decaying hadronically and the other one leptonically. A particle-level simulation of this signal and its…
A search for new phenomena in events with two same-charge leptons or three leptons and jets identified as originating from $b$-quarks in a data sample of 36.1 fb$^{-1}$ of $pp$ collisions at $\sqrt{s}= 13$ TeV recorded by the ATLAS detector…
The results of a search for vector-like top quarks using events with exactly one lepton, at least four jets, and large missing transverse momentum are reported. The search is optimised for pair production of vector-like top quarks in the…
We illustrate the utility of jet mass distributions as probes of new physics at the LHC, focusing on a heavy vector-quark doublet that mixes with the top as a concrete example. For 1 TeV vector-quark masses, we find that signals with…