Related papers: Mixed Stops and the ATLAS on-Z Excess
Dynamical theories of dark energy predict new degrees of freedom with particular environmental sensitivity to avoid constraints on fifth forces. We show that the similar, yet complementary multi-purpose detector setup of the ATLAS and CMS…
The ATLAS and CMS experiments at LHC observe small excesses of diphoton events with invariant mass around 750 GeV. Here we study the possibility of nearly parity degenerate and vector-scalar degenerate spectra as well as composite dynamics…
The search for physics beyond the Standard Model (BSM) is one of the most important goals for the general purpose detector ATLAS at the Large Hadron Collider at CERN. Supersymmetry search strategies based on generic event signatures of high…
R-parity violation in supersymmetry gives rise to many unique experimental signatures. We describe searches with the ATLAS detector for supersymmetry with R-parity violating decays. Examples include searches for resonant sneutrino decays to…
Light stops are a hallmark of the most natural realizations of weak-scale supersymmetry. While stops have been extensively searched for, there remain open gaps around and below the top mass, due to similarities of stop and top signals with…
This talk presents results from the CMS and ATLAS Collaborations from searches for physics beyond the Standard Model motivated by supersymmetry from Run 1 of the LHC. Representative searches are described to illustrate the diverse nature of…
Results are presented of a search for supersymmetric particles decaying into final states with significant missing transverse momentum and exactly two identical flavour leptons (e or mu) of opposite charge in sqrt{s}=7 TeV collisions at the…
The resonant excesses around 2 TeV reported by the ATLAS Collaboration can be explained in the left-right model, and the tight constraints from lepton plus missing energy searches can be evaded if the $SU(2)_R$ gauge symmetry is…
Measurement of the inclusive and differential top-quark charge asymmetry is carried out using full Run 2 data from proton-proton collisions at a center-of-mass energy of $13$ TeV collected by the ATLAS detector. The single-lepton and…
We study the most promising signals of Constrained Minimal Supersymmetry detectable at a luminosity upgraded 2 TeV Fermilab Tevatron collider. Using a full event-level Monte Carlo based on Pythia/Jetset, we simulate the trilepton signal…
We propose a new possible explanation of the ATLAS di-boson excess: that it is due to heavy resonant slepton production, followed by decay into di-smuons. The smuon has a mass not too far from the W and Z masses, and so it is easily…
Natural realisations of supersymmetry require light stops ${\tilde t}_1$, making them a prime target of LHC searches for physics beyond the Standard Model. Depending on the kinematic region, the main search channels are ${\tilde t_1}\to t…
The four-lepton final state, rare in standard model processes, is an attractive channel for new physics searches at the LHC. In supersymmetry (SUSY), charged leptons may arise from R-Parity conserving (RPC) cascade decays of SUSY particles…
Precise measurements of the properties of the top quark test the Standard Model (SM) and can be used to constrain new physics models. The top quark pair charge asymmetry is an asymmetry predicted to occur beyond leading-order QCD in the SM,…
ATLAS and CMS recently released the first results of searches for diphoton resonances in 13 TeV data, revealing a modest excess at an invariant mass of approximately 750 GeV. We find that it is generically possible that a singlet scalar…
During the last years ATLAS and CMS have reported a number of slight to mild discrepancies in signatures of multileptons plus $b$-jets in analyses such as $t\bar t H$, $t\bar t W^\pm$, $t\bar t Z$ and $t\bar t t\bar t$. Among them, a recent…
The ATLAS detector is used to search for excited leptons in the electromagnetic radiative decay channel l* --> l+gamma. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an…
The standard in the high energy physics community for claiming discovery of new physics is a $5\sigma$ excess in the observed signal over the estimated background. While a $3\sigma$ excess is not enough to claim discovery, it is certainly…
Motivated by a small but intriguing excess observed in the decay mode $ H\rightarrow \ell^+\ell^- \gamma$ reported by both the ATLAS and CMS collaborations, we explore the possibility that new physics contributes directly to the effective $…
In supersymmetric models a large average stop mass $M_S$ is well known to both boost the lightest Higgs boson mass $m_{h}$ and also make radiative electroweak symmetry breaking unnaturally tuned. The case of `maximal mixing', where the stop…