Supersymmetry (SUSY) is an attractive extension of the Standard Model possibly solving many standing issues in particle physics and cosmology. The general purpose ATLAS detector at the Large Hadron Collider (LHC) is an experiment capable of discovering or excluding TeV SUSY. However discovery can only be claimed when the Standard Model backgrounds are understood and are under control. The expectations at the LHC are that Monte Carlo simulation predictions may not be sufficient to achieve this and the backgrounds will have to determined from data itself. In this note we will highlight some data driven methods developed to estimate backgrounds and detect a possible SUSY excess.
We present recent work performed in ATLAS on techniques used to reconstruct the decays of SUSY particles at the LHC. We concentrate on strategies to be applied to the first fb-1 of LHC data.
In this paper we briefly discuss the estimation of uncertainties in QCD backgrounds to searches for Supersymmetry under development by the ATLAS collaboration.
Already with very first data, the ATLAS experiment should be sensitive to a SUSY signal well beyond the regions explored by the Tevatron. We present a detailed study of the ATLAS discovery reach in the parameter space for various SUSY models. The expected uncertainties on the background estimates are taken ito account.
Recent results on searches for third generation supersymmetry carried out by the ATLAS collaboration with 2.05 fb-1 of sqrt(s) = 7 TeV pp collisions recorded with the LHC in 2011 are reported. These analyses focus on search for gluino- and squark-mediated stau production, direct scalar bottom pair production and gluino-mediated sbottom and stop pair production.
Supersymmetry (SUSY) is one of the most relevant scenarios of new physics searched by the ATLAS experiment at the CERN Large Hadron Collider. In this writeup the principal search strategies employed by ATLAS are outlined and the most recent results for analyses targeting SUSY discovery are discussed. A wide range of signatures is covered motivated by various theoretical scenarios and topologies: strong production, third-generation fermions, long-lived particles and R-parity violation, among others. The results are based on up to ~5 fb-1 of data recorded during 2010-2011 at sqrt(s) = 7 TeV cent…
We discuss how the CMS and ATLAS experiments are preparing for the analysis of first LHC data with emphasis on the search for supersymmetry. We will show the importance of the understanding of detector, trigger, reconstruction and backgrounds, and we will present realistic estimates of the reach of CMS and ATLAS.
The CERN Large Hadron Collider (LHC) is scheduled to commence operation in 2008 and inclusive searches for supersymmetry (SUSY) will be one of our primary tasks in the first days of LHC operation. It is certain that the final state of multijets + missing transverse energy will provide a superior performance in SUSY searches. Strategies to understand the instrumental background and to understand the Standard Model (SM) background are still under development and are urgent issues for the coming data. We describe the strategy for early SUSY searches at the ATLAS experiment using the fist data cor…
First ATLAS searches for signals of Supersymmetry in proton-proton collisions at the LHC are presented. These searches are performed in various channels containing different lepton and jet multiplicities in the final states; the full data sample recorded in the 2010 LHC run, corresponding to an integrated luminosity of 35 $\rm{pb}^{-1}$, has been analysed. The limits on squarks and gluinos are the most stringent to date.
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. Already with early LHC data, the ATLAS experiment should be sensitive to discover physics beyond the Standard Model. This paper summarizes the prospects of the ATLAS experiment to find experimental evidence for Supersymmetry (SUSY) and Universal Extra Dimensions (UED) in channels with jets, leptons and missing transverse energy for an integrated luminosity of L = 200pb-1 at a centre-of-mass energy sqrt s = 10 TeV. Only a selectio…
Supersymmetry is one of the most motivated scenarios for physics beyond the Standard Model. This article summarizes recent ATLAS results on searches for supersymmetry in proton-proton collisions at a centre-of-mass energy of 13 TeV at LHC, which target supersymmetric particles produced by strong interaction in events with leptonic final states. No significant excess above the Standard Model expectation is observed and exclusion limits have been set on squark and gluino masses in various scenarios.
We present a review of the SUSY search strategies in ATLAS in conjunction with a readiness of the detector systems for first collision data in 2009 fall. Commissioning was performed with the LHC single beams and the cosmic ray data in 2008. The talk covers the analysis strategies based on the large Etmiss plus high pT multi-jets signature in which the number of methods are investigated to extract background estimation from real data. The expected discovery reach with inclusive analysis is shown. The review also covers the special signature searches for certain SUSY scenarios, where specific de…
The ATLAS detector has begun the search for new physics beyond the Standard Model (BSM) with \int L dt = ~45 pb^-1 of data collected in 2010. After no significant evidence of new physics was found in the data, limits on possible signatures have been set, many of which have already placed more stringent limits than previous measurements. These proceedings review recent limits obtained on various BSM models, including excited quarks, axigluons, contact interactions, quantum black holes, heavy gauge bosons (W', Z'), gravitons, fourth-generation quarks and leptoquarks.
We present the status of interpretations of Supersymmetry (SUSY) searches in ATLAS at the Large Hadron Collider (LHC) using simplified models. Such models allow a systematic scan through the phase space in the sparticle mass plane, and in the corresponding final state kinematics. Models at various levels of simplification have been studied in ATLAS. The results can be extrapolated to more general new physics models which lead to the same event topology with similar mass hierarchies. Searches in the no-lepton channel with 1.04 fb^-1 of data from 2011 and the same-sign dilepton channel with 35 p…
Using ATLAS data corresponding to 70 +- 8 nb^-1 of integrated luminosity from the 7 TeV proton-proton collisions at the LHC, distributions of relevant supersymmetry-sensitive variables are shown for the final state containing jets, missing transverse momentum and one isolated electron or muon. With increased integrated luminosities, selections based on these distributions will be used in the search for supersymmetric particles: it is thus important to show that the Standard Model backgrounds to these searches are under good control.
HIGGS and SUSY searches performed by the ALEPH Experiment at LEP are interpreted in the framework of two constrained R-parity conserving models: Minimal Supergravity and minimal Gauge Mediated Supersymmetry Breaking.
Searches for SUSY particles have been performed in 3.6 fb$^{-1}$ e$^+$e$^-$ data collected by the LEP detectors at $\sqrt{s}$ between 90 GeV and 209 GeV. This talk reviews some of the relevant searches for SUSY particles at LEP. No excess of events is observed in any channel. Results are interpreted in the context of the MSSM.
Searches for supersymmetry (SUSY) are very important tasks at the Large Hadron colleder(LHC). If SUSY exists at the TeV scale, clear excess above the Standard Model (SM) background will be observed. SM background should be estimated from real data self. In this paper, we descrive the strategy for the early SUSY searches at the LHC and focus on the data-driven estimation of the SM background in the early stage of collision.
The CDF and DO experiments have collected and analyzed about 300 inverse picobarns of data during the Run II of the Tevatron. Results of searches for new non supersymmetric particles based on these datasets will be presented.
We report results from searches for supersymmetry with trileptons plus missing transverse energy and diphotons plus missing transverse energy made using the D0 detector at the Fermilab Tevatron collider. These searches are optimized for MSSM SUSY and GMSB, respectively. New limits are set on the considered SUSY models. This article is the proceedings for a parallel talk given at ICHEP08.
Supersymmetry will be searched for in a variety of final states at the LHC. It is crucial that a robust, efficient and unbiased trigger selection for SUSY is implemented from the very early days of data taking. After a brief description of the ATLAS and the CMS trigger systems, and a more in-depth discussion of the ATLAS High-Level Trigger, a triggering strategy is outlined for early SUSY searches at the LHC.
The CMS and ATLAS search strategy for SUSY in inclusive multijet plus high missing transverse energy final states is reviewed. This canonical SUSY signature may be a viable discovery channel for low mass SUSY in the early phase of the LHC. Methods for Standard Model background estimates, MET studies and filters for instrumental background are presented.
Searches for supersymmetry (SUSY) models with a compressed mass spectrum are theoretically motivated but also pose experimental challenges. Two recent searches from the CMS Collaboration targeting leptonic final states that can originate from such models are presented. The first search investigates SUSY signatures with two opposite sign or three low momentum leptons, while the second probes the parameter space of top squark models, where the mass difference of the lightest SUSY particles is close to the mass of the top quark. Both searches are based on the full dataset collected by CMS during …
In this article results from supersymmetry searches at D0 and CDF are reported. Searches for third generation squarks, searches for gauginos, and searches for models with R-parity violation are described. As no signs of supersymmetry for these models are observed, the most stringent limits to date are presented.
Results of searches at the Tevatron for physics (non-SUSY and non-Higgs) beyond the Standard Model using 200/pb to 480/pb of data are discussed. Searches at DO and CDF for Z', Lepton-Quark compositeness, Randall-Sundrum Gravitons, Large Extra Dimensions, W', Leptoquarks and Excited Electrons are presented here.
The Tevatron collider has provided the CDF and D0 collaborations with large datasets as input to a rich program of physics beyond the standard model. The results presented here are from recent searches for SUSY particles using up to 6 fb-1 of data.
Recent searches for non-SUSY exotics in $p\bar{p}$ collisions at a center-of-mass energy of 1.96 TeV at the Tevatron Run II are reported. The emphasis is put on the results of model-driven analyses which were updated to the full Run IIA datasets corresponding to integrated luminosities of about 1 $fb^{-1}$.
The latest results on searches for stop and sbottom squarks are presented. Searches for direct squark production in a variety of decay channels are reviewed. The results are based on 19.5/fb of LHC proton-proton collisions at sqrt = 8 TeV taken with the CMS detector.
I describe recent signature-based searches for anomalous physics processes using up to 2.9/fb of data from the CDF or D0 detectors at the Fermilab Tevatron. While each search conveys its sensitivity by interpreting a null result in terms of one or more specific exotic models, the searches are designed to be broadly sensitive to many models.
The results of search for Supersymmetry performed at the Tevatron Collider by the CDF and D0 collaborations are summarized in this paper. No significant deviations with respect to the Standard Model expectations were observed and constraints were set on supersymmetric parameters.
We present the recent prospects and strategies of the ATLAS and CMS experiments in the search for signatures of Supersymmetry. The emphasis is placed on standard signatures with missing transverse energy and on the initial data taking periods.
The CDF and D0 collaborations have results on a large number of searches for beyond-the-standard-model phenomena. This talk focuses on searches for non-supersymmetric model signatures. These results, based on between 1--2.5 fb-1 of data from p pbar collisions at the Fermilab Tevatron, include some of the world's best limits on extra dimensions models and heavy resonances.
Multiple searches for supersymmetry have been performed at the CMS experiment. Of these, inclusive searches aim to remain as sensitive as possible to the widest range of potential new physics scenarios. The results presented in this talk use the latest 19.5 fb$^{-1}$ of 8 TeV data from the 2012 LHC run. Interpretations are given within the context of Simplified Model Spectra for a variety of both hadronic and leptonic signatures.
This article presents recent results of searches for Supersymmetry using the CDF and the D$\not$O detector at the Fermilab Tevatron Collider. Described are the Tevatron searches for third generation scalar quarks and for supersymmetric signatures involving photons. All the reported results have been obtained assuming theoretical models in which $\mathcal{R}$-parity is conserved.
As the integrated luminosity of the Run II Tevatron increases, the sensitivity to new physics is approaching and in some cases surpassing that previously attained in Run I. Presented below are a selection of new results from searches for physics beyond the Standard Model at the CDF and D0 experiments.
Highlights of the search for SUSY at ATLAS are presented emphasising on the variety of searches that were performed in the LHC Run I in p-p collisions at a centre of mass of 7 TeV and 8TeV. Searches for squars, gluinos, third generation squarks and electroweakinos in R-parity conserving scenarios and an example of searches in R-parity violating scenarios are highlighted.
Recent results from searches for non-supersymmetric particles by the CDF and D0 collaborations are reported. The sample taken during the RunII of the Fermilab T eVatron collider at Ecms=1.96 TeV is used. The integrated luminosity analyzed ranges from 300 to 1020 pb-1 depending on the search.}
Numerous searches for evidence of supersymmetry at the Tevatron have been performed by the CDF and D0 collaborations. Recent results are presented here including squarks and gluinos in jets and missing transverse energy, stop in several different decay modes, charginos and neutralinos in trileptons, neutralinos in di-photons, R-parity violating sneutrinos in e+mu events, and long-lived particles. These explore many variations of SUSY such as MSSM, mSUGRA, and GMSB. While no evidence of SUSY production is observed, 95% CL limits on cross sections and SUSY parameter space are set. Most of these …
Searches for supersymmetric particles at LEP are first reviewed, with some emphasis on the mass limit for the lightest neutralino. The framework is the MSSM with R-parity conservation, with brief excursions towards mSUGRA and GMSB. Next, recent results obtained in the Run II of the Tevatron are presented.
Supersymmetric particles that are long-lived or violate R-parity could evade many conventional searches for supersymmetry. This talk presents the latest results of searches for supersymmetry with long-lived particles or R-parity violation performed by the ATLAS and CMS collaborations using $\sim$20 fb$^{-1}$ of proton-proton collisions at center-of-mass energy of 8 TeV delivered by the LHC.
We present the most recent results on searches for squarks and gluinos in ppbar collisions at sqrt(s)=1.96 TeV, in events with large missing transverse energy, leptons and multiple jets in the final state, based on 1.8 to 2.8 fb-1 of data collected by the CDF Run II detector at the Tevatron. No evidence of new physics is found and exclusion limits in several MSSM scenarios are extracted.
The results of searches for several type of physics beyond the Standard Model using data from the four LEP experiments are presented. In the absence of any excess signal events seen in the data limits are placed on the existence of extra-dimensions, gauge mediated supersymmetry and some exotic states.
Searches for R-parity conserving supersymmetric particles have been performed in e+e- data collected by LEP detectors, at centre-of-mass energies up to 209GeV, corresponding to an integrated luminosity of 3.1fb-1. The results and their interpretation in the context of MSSM frameworks are briefly reviewed.
Searches for physics beyond the Standard Model of particle physics are about to enter a new era with the startup of the Large Hadron Collider (LHC) at CERN. Prospects for R-parity conserving supersymmetry discovery and measurements with the ATLAS detector at the LHC are presented. Methods for determining the parameters of the underlying supersymmetry model and the relation to dark matter estimation are discussed.
We study the impact of the jets and missing transverse momentum SUSY analyses of the ATLAS experiment on the phenomenological MSSM (pMSSM). We investigate sets of SUSY models with a flat and logarithmic prior in the SUSY mass scale and a mass range up to 1 and 3 TeV, respectively. These models were found previously in the study 'Supersymmetry without Prejudice'. Removing models with long-lived SUSY particles, we show that 99% of 20000 randomly generated pMSSM model points with a flat prior and 87% for a logarithmic prior are excluded by the ATLAS results. For models with squarks and gluinos be…
We present recent results from searches for new physics beyond supersymmetry performed at the Tevatron accelerator at Fermilab. The CDF and D0 analyses presented here utilized data of integrated luminosity up to 6 fb-1. We cover leptonic and bosonic resonances interpreted in the Randall-Sundrum graviton and new-boson models, rare final states, and the search for vector-like quarks.
Highlights are presented of current searches for supersymmetry produced in proton-proton collisions at the LHC, operating at sqrt(s)=7TeV. Searches with missing transverse energy are summarized from both the ATLAS and CMS experiments. A wide range of final states is covered, including recent searches with photons, leptons, and purely hadronic final states. Future developments are anticipated with extra focus on exclusive searches in electroweak and third-generation supersymmetry production.
Various searches for leptoquarks, scalar quarks in $R_p$-violating supersymmetric models, and excited fermions performed by the HERA experiments H1 and ZEUS are reviewed. No evidence for new particle production was observed from data collected by both experiments since 1994 in either electron-proton and positron-proton collisions. Stringent limits derived on the masses and couplings of these new particles are compared whenever appropriate with those from LEP, the Tevatron and low energy experiments.
The most recent results for searches for the Standard Model Higgs boson at a center-of-mass energy of sqrt(s) = 7 TeV using 4.9/fb of data collected with the ATLAS detector at CERNs Large Hadron Collider are presented.
The prospects of the ATLAS and CMS experiments at LHC for beyond standard model searches are depicted in this document. The presented studies concentrate on the search plans for supersymmetry (SUSY) and beyond in the first few years of data taking.
Searches for rare and exotic Higgs decays using proton-proton collision data with the center-of-mass energy of 8 TeV and 13 TeV collected with the ATLAS detector are presented. Various final states are considered. No significant deviations from the Standard Model expectations are found. The results are interpreted in different Beyond Standard Model theories.
A summary of the sensitivity of the ATLAS and CMS experiments at the LHC to discover a Standard Model Higgs boson is presented. Some prospects for Minimal Supersymmetric Standard Model Higgs searches at LHC are also included.
Many theories beyond the Standard Model predict new phenomena which decay to well isolated, high-$p_{\text{T}}$ leptons. Searches for new physics with these signatures are performed using the ATLAS experiment at the LHC. The results reported here use the pp collision data sample collected by the ATLAS detector at the LHC with a center-of-mass energy of 13 TeV.
Searches for pair and single production of supersymmetric particles under the assumption that R-parity is violated via a single dominant coupling are presented. A subset of the most recent results from LEP, Tevatron and HERA is selected. The data are in agreement with the Standard Model expectation. Limits on the production cross sections and the masses of supersymmetric particles are derived.
Searches for topologies predicted by gauge-mediated SUSY breaking models were performed using data collected with the L3 detector at LEP. All possible lifetimes of the next-to-lightest SUSY particle (NLSP), neutralino or scalar tau, were considered. No evidence for these new phenomena was found and limits on the production cross sections and sparticle masses were derived. A scan over the parameters of the minimal GMSB model was performed, leading to lower limits of 62.2 GeV, 11 TeV, and 0.07 eV on the NLSP mass, the mass scale parameter Lambda, and the gravitino mass, respectively. The status …
One of the main goals of the ATLAS detector at the LHC of CERN, a proton-proton collider with a nominal centre-of-mass energy of 14 TeV, is to search for New Physics beyond the Standard Model (BSM). A widely favoured BSM candidate is Supersymmetry (SUSY), which postulates a superpartner for each Standard Model particle. The first part of this thesis describes a strategy for an early discovery of SUSY using the trilepton signature, with a focus on gravity-mediated SUSY breaking, mSUGRA. The discovery potential for SUSY for the case where strongly interacting supersymmetric particles are very ma…
The latest results of long-lived particle (LLP) searches from the ATLAS Experiment at the Large Hadron Collider are presented. Analyses are presented with a focus on detector subsystem needed to discern the LLP signature from Standard Model background, and the custom reconstruction requirements for sensitivity. Results are contextualized with updated summary plots for key new physics candidates, along with notes for future LLP searches.
This work presents a new inclusive search for supersymmetry (SUSY) by the ATLAS experiment at the LHC in proton-proton collisions at a center-of-mass energy sqrt(s) = 7 TeV in final states with jets, missing transverse momentum and one or more isolated electrons and/or muons. The search is based on data from the full 2011 data-taking period, corresponding to an integrated luminosity of 4.7 inverse fb. Single- and multi-lepton channels are treated together in one analysis. An increase in sensitivity is obtained by simultaneously fitting the number of events in statistically independent signal r…
Selected results from searches for new physics with unconventional signatures using the ATLAS and CMS detectors are presented. Such signatures include emerging jets, heavy charged particles, displaced or delayed objects, and disappearing tracks. These signatures may arise from hidden sectors or supersymmetric models. The searches use proton-proton collision data from Run 2 of the LHC with a center-of-mass energy of 13 TeV.
